Annual Report STATE LOAD DESPATCH CENTRE GUJARAT ENERGY TRANSMISSION CORPORATION LTD

Transcription

1 Annual Report STATE LOAD DESPATCH CENTRE GUJARAT ENERGY TRANSMISSION CORPORATION LTD

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5 FROM THE CHIEF ENGINEER S DESK I am pleased to present the Annual Report of SLDC, Gujarat for the financial year SLDC s role in electricity sector is both vital and exceptional. SLDC is an essential link in the safe, cost-effective delivery of electric power across the State. Customer service, effective communication and operational excellence are the principles that guide us as we explore better ways to keep power moving safely, efficiently and reliably. Year was undeniably a period of major challenges for the grid operation. Despite all odds, SLDC has put up its best efforts to minimize deviation by prompting and sensitizing load and RE generation forecasting activity. The gross generation capacity addition was 8.56% (2133 MW) during the year The energy supplied had increased by 1.11% as compared to last year. The energy received from renewable sources (Wind and Solar only) is 9458 MUs (9.06% of total energy). In the month of April May 16, there were many bigger sized units under forced shutdown. Also, the variable cost of around 1000 MW gas based generators had increased drastically due to non-availability of gas under E-bid RLNG. At that time SLDC had performed an active role by deferring many unit outages and expediting revival of units which were under forced / planed outages to maintain adequacy of power supply looking to onset of summer. On 13th July 2016 at 02:37 A.M, there was 2820 MW generation loss at CGPL, Mundra. At that time, many proactive actions were taken by SLDC-Gujarat in order to maintain load - generation balance of the Gujarat power system. GWRDC availed Ukai left bank main canal (ULBMC) outage for 60 days from for major repairing work. During outage, it was not possible to keep all units of UHPS and UTPS except UTPS Unit No. 6 on bar due to acute water shortage. SLDC proactively coordinated all activities like ensuring water requirement of UTPS Unit No. 6, procurement of cheaper gas for NTPC s Kawas and Jhanor plants, augmentation of 315 MVA ICT at Ukai, unit outages at Ukai etc. Before facilitating ULBMC outage, The outage of 400/220 KV, 315 MVA ICT at Ukai was facilitated for augmentation work timely. The power system of South Gujarat was well managed securely and reliably by SLDC. Initiatives for Improvement: A lot of initiatives were taken to improve operational performance. During the year , two black start mock drills were carried out with objective of restoration of total system in the shortest possible time in case of large scale black out. All these exercises were distinct. In one exercise, two gas based Power Stations (Kawas and Jhanor) of NTPC participated jointly and in other exercise one hydro unit of RBPH and one gas based unit of CLPIPL participated jointly. SLDC had taken proactive steps to inform the field offices and other related agencies to avail the outages of important elements as and when there were opportunities in the system. Also, SLDC had made fabulous efforts to facilitate outages for construction of new EHV lines and for R & M work of EHV lines so

6 as to accommodate new elements in the grid at the right time. The outage of ± 500 KV Mundra - Mohindergadh HVDC Bipole outage was facilitated on for crossing work of 400 KV D/C Charanka - Sankhari line. At that time, generation at APL was restricted to 3000 MW to manage safe loading on AC network in Kutch and North - Gujarat area. 132 KV Nyara - Vajadi & 132 KV Nyara - Vikram line simultaneously for continuous five days was facilitated for line shifting and height raising work. The continuous outage of 400 KV D/C Vadavi - Dehgam line for 20 days and 18 days continuous outage of 400 KV CLPIPL Kasor line for rerouting of lines to facilitate DFCC crossing were facilitated. SLDC has taken keen interest to relieve congestion in the network by proposing worthwhile changes in network topology and getting them implemented through the concerned agencies so as to have a secure and reliable grid operation. As a result, the interconnection of 400 KV Ukai - Kosamba line No. 2 & 400 KV Jhanor - Dastan line No. 1 (so as to form 400 KV S/C UTPS Navsari line and 400 KV S/C Jhanor Kosamba line) has been established. Also, direct 220 KV links (one is 220 KV Kosamba - Ichhapore and another is 220 KV GSEG - Sachin line) have been established in South -Gujarat. It improves the reliability of power supply in South Gujarat area. SLDC has taken up the matter with WRPC regarding delay in scheduling of URS power of CGPL on account of late consent by the Utilities. SLDC informed that there is no need to take consent of respective SLDCs (whose beneficiaries has surrendered the share) / Discoms / Generators in exigency condition because their owned share has been allocated as per the scheduling procedure of IEGC without informing / taking consent of State SLDC / beneficiaries who has availed URS. It has been informed that URS of UMPP shall be allocated promptly to the beneficiary in need as per the scheduling procedure. In case of exigency condition, it shall be allocated as soon as possible without taking consent of the Generators / State SLDCs who has surrender the share so as to avoid delay in scheduling of URS power of CGPL on account of late consent by the Utilities. SLDC has done remarkable work accessing reliable data of renewable energy generation in real time which is very much helpful to recognize trend of RE generation and handle its variation. The service provider is finalized now. SLDC is getting more accurate forecasting of RE generation. At present, SLDC is getting day ahead, real time and weekly wind generation forecast for State as whole through online web based application from service provider. SLDC has developed in house wind energy generation forecasting module. SLDC is continuously analysing trend of wind energy generation forecast provided by FSP and provided by in house module. SLDC is continuously monitoring real time trend with forecasted generation. It is being regularly utilised for system analysis and better forecasting purpose. Also, a keen initiative has been taken for hiring load forecasting service, The service provider will be finalized soon. Our SCADA & IT team had done outstanding work for data visualization, maintaining RTU availability and communication link with control centre. Lot of efforts are made for accessing of various data by users from SLDC website which maintains a high degree of translucent environment. SLDC Gujarat is equipped with WAMS technology using Synchro phasor. Over hundred PMUs are commissioned at 25 locations. The Phasor Data Concentrator (PDC) is commissioned at SLDC which is capable of handling 1500 phasors. This facility is very much helpful for early detection of any forthcoming harmful event to the grid so as to respond quickly.

7 SLDC is equipped with NEW SCADA hardware. Also, the Back-up SLDC has been established at Gandhinagar with advanced IT and hardware infrastructures. It has been successfully tested. It will be helpful to manage the system in case of any disaster at main control centre. SLDC believes in knowledge sharing and skill enhancement of each of its working associates. Almost in all capacity building workshops and training programs, SLDC officials are delegated. Also, in-house discussion sessions are regularly arranged so that each individual s skill and area of interest is candidly recognized. As a result, many technical papers and presentations have been presented in various national and International summits by SLDC officials. A one day non-residential workshop on Power System Restoration was organized on (Saturday) at Gujarat Energy Training & Research Institute (GETRI), near 132 KV Gotri Substation, Gotri Road, Gotri, Vadodara. The workshop aimed to familiarize participants on Gujarat Power System, Role of defence Mechanisms, Role of each utilities during black out, Power system restoration approach, sharing of mock drill experience and to acquaint with Gujarat Power System restoration procedure etc. Officers and delegates from WRLDC, all generating Stations in Gujarat, NCA, GETCO, SLDC-Gujarat, Sub SLDC s, Railway, Discoms were invited. Almost 100 officials attended the workshop. I, on behalf of SLDC staff, take this opportunity to convey my sincere thanks to Shri S. K. Negi (Former MD, GETCO) for providing an excellent guidance and invaluable support and leading MD, GETCO Shri B. B. Chauhan for strengthening the State grid by executing various important transmission projects timely. All our efforts in preparation of this Annual Report would rather go in vain if I fail to thank GoG, GUVNL, GERC, WRPC, WRLDC (POSOCO) and beneficiaries and all others related to grid operation for rendering their continuous support, active involvement and kind cooperation. With Best Regards, (B.B. Mehta) Chief Engineer State Load Despatch Centre

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9 TABLE OF CONTENTS 1. INTRODUCTION Formation Functions SALIENT FEATURES OF THE GUJARAT GRID Installed Capacity Sector wise Fuel wise Transmission Network as on State Distribution Companies in Gujarat & their contracted capacity(mw) inas on DEMAND FACTS... 6 Month wise Maximum Demand Catered in MW ENERGY GENERATION FACTS Sector wise Energy Generation (in MUs) Monthly Sector wise Energy Generation (MUs) State Generating Station wise Energy Generation for Year Thermal Units Gas Units Hydro Units Others RENEWABLE ENERGY GENERATION ABSORPTION Wind Energy Generation Facts Monthly Wind Energy Generation in Mus Month wise Maximum Wind Energy Generation in MW Month wise Maximum Wind Energy Generation in MUs Hourly Wind Energy Injection Trend during the year Maximum variation in wind energy generation in MUs on two consecutive days Solar Energy Generation Facts Month wise Solar Energy Generation in MUs Month wise Maximum Solar Energy Generation in a day in MWH Month wise Maximum Solar Energy Generation in a day in MUs Hourly Solar Energy Generation Pattern during the FY Typical Solar Generation Captured DISCOM-WISE DEMAND FACTS DISCOM wise Energy Catered Category wise Energy Supplied in MUs by State Discoms DISCOM wise Category wise energy supplied in MUs Month - wise Category - wise energy supplied in MUs:... 18

10 7. VOLTAGE PROFILE STATISTICS AT IMPORTANT NODES FREQUENCY PROFILE STATISTICS Monthly Average Frequency Trend for Last Three Financial Years Monthly Frequency Trend GENERATION CAPACITY ADDITION /DECOMMISSIONED GRID EXPANSION EHV lines added in Gujarat Grid during year MAJOR INCIDENTS MONTHLY GETCO NETWORK LOSSES (%) ENERGY ACCOUNTING & SETTLEMENT AND STOA DETAILS ABT Meters Registered for Data Processing at SLDC Nos. of active UI Pool Members in UI Pool Account of SLDC Users Registered under REC Mechanism Short Term Open Access Applications Processed SCADA & IT UPDATES Data Acquisition Updates IT Updates FINANCIAL FACTS & FIGURES Aggregate Revenue Requirement for the FY Major Figures for the FY CAPEX Plan of SLDC FUTURE OUTLOOK & NETWORK IMPROVEMENT State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 2

11 1. INTRODUCTION 1.1 FORMATION As per Energy & Petrochemical Department, Government of Gujarat, Order No. GHU-04-32GEB K of 29 th May 2004, established the load despatch centre, Jambuva as State Load Despatch Centre, for purposes of exercising the power and discharging functions under section 31 of IEA FUNCTIONS In accordance with section 32 of Electricity Act, 2003, the State Load Despatch Centre (SLDC) has to carry out following functions: a. SLDC has to ensure integrated operation of the power system in a State. b. SLDC is responsible for optimum scheduling and despatch of electricity within a State. c. Monitor grid operations; d. keep accounts of the quantity of electricity transmitted through the State grid; e. Exercise supervision and control over the intra-state transmission system; f. SLDC is responsible for carrying out real time operations for grid control and despatch of electricity within the State through secure and economic operation of the State grid in accordance with the Grid Standards and the State Grid Code. g. SLDC in a State may give such directions and exercise such supervision and control as may be required for ensuring the integrated grid operations and for achieving the maximum economy and efficiency in the operation of power system in that State. h. Every licensee, generating company, generating station, sub-station and any other person connected with the operation of the power system shall comply with the directions issued by the SLDC. i. The SLDC shall comply with the directions of the Regional Load Despatch Centre. j. In case of inter-state bilateral and collective short-term open access transactions having a state utility or an intra-state entity as a buyer or a seller, SLDC shall accord concurrence or no objection or a prior standing clearance. k. The following are contemplated as exclusive functions of SLDC. a. System operation and control covering contingency analysis and operational planning on real time basis; b. Scheduling / re-scheduling of generation; c. System restoration following grid disturbances; d. Metering and data collection; e. Compiling and furnishing data pertaining to system operation; f. Operation of state UI pool account, state reactive energy account. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 3

12 Annual Report SALIENT FEATURES OF THE GUJARAT GRID 2.1 INSTALLED CAPACITY SECTOR WISE Installed Capacity (MW) State Sector Private Sector Central Sector Wind Farm Solar Biomass Mini Hydro Total As on As on As on As on As on As on State Sector Private Sector Central Sector Wind Farm Solar As on As on As on As on As on As on FUEL WISE Period Thermal Gas Hydro Nuclear Solar Wind Farm Biomass Total As on As on As on As on As on As on Thermal Gas Hydro Nuclear Solar Wind Farm Biomass As on As on As on As on As on As on State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 4

13 2.2 TRANSMISSION NETWORK AS ON Sr. No. Voltage Class No. of Substations As on As on Transmission Lines in circuit Km No. of Substations Transmission Lines in circuit Km KV KV KV /33 KV Total STATE DISTRIBUTION COMPANIES IN GUJARAT & THEIR CONTRACTED CAPACITY(MW) INAS ON Sr. No. Name of the Company Contracted Capacity from conventional sources in MW as on PGVCL UGVCL DGVCL MGVCL 2164 State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 5

14 Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Annual Report DEMAND FACTS MONTH WISE MAXIMUM DEMAND CATERED IN MW Maximum Demand catered of last Ten years Max demand catered in MW Max demand catered in MW No of days when demand difference between Maximum and Minimum demand in a day remains more than 2000 MW Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 6

15 Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Annual Report ENERGY GENERATION FACTS 4.1 SECTOR WISE ENERGY GENERATION (IN MUS) Year GSECL Private Sector Central Sector Wind Energy Solar Biomass Mini Hydro Total MUs MONTHLY SECTOR WISE ENERGY GENERATION (MUS) Month GSECL Private Central sector WEG Solar Biomass Mini Hydro Total MUs Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Total % Contribution Month wise energy supplied (in MUs) YEAR YEAR YEAR State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 7

16 4.3 STATE GENERATING STATION WISE ENERGY GENERATION FOR YEAR THERMAL UNITS Unit Unit Capacity (MW) Generation (MUs) GANDHINAGAR GTPS GTPS GTPS WANAKBORI WTPS WTPS WTPS WTPS WTPS WTPS WTPS UKAI(TH) UTPS UTPS UTPS UTPS UTPS UTPS SIKKA STPS STPS STPS STPS PANANDHRO KLTPS KLTPS KLTPS KLTPS TORRENT POWER AECO C AECO D AECO E AECO F SURAT LIGNITE SLPP SLPP SLPP SLPP AKRIMOTA ALPP ALPP APL APL APL State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 8

17 APL APL APL APL APL APL APL Essar Vadinar EPGL EPGL OPGS OPGS OPGS BECL BECL BECL Total Thermal generation GAS UNITS Unit Unit Capacity (MW) Generation (MUs) DHUVARAN GAS DTPS - GT DTPS -STG DTPS-GT DTPS-STG DGB GT UTRAN Stage-2 UGPP GT UGPP ST GIPCL-I GIPCL GT GIPCL GT GIPCL GT GIPCL ST GIPCL-II GIPCL GT GIPCL ST CLPIPL GPEC GT GPEC GT GPEC GT GPEC STG GSEG Stage-1 GSEG GSEG GSEG ST GSEG Stage-2 GT STG State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 9

18 SUGEN SUGEN GT SUGEN GT SUGEN GT UNO SUGEN UNO SUGEN GPPCL GPPCL GPPCL Total Gas Generation HYDRO UNITS Unit Unit Capacity (MW) Generation (MUs) UKAI(HY) UHPS UHPS UHPS UHPS UKAI LBCH ULBC ULBC KADANA KHPS KHPS KHPS KHPS PANAM PANAM PVT HY. MADHUBAN DAM MADHUBAN DAM MADHUBAN DAM Karjan Dam Total Hydro Generation OTHERS Others Generation (MUs) CPP Wind Farm Solar Biomass Central Sector Total Energy Generation State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 10

19 Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Annual Report RENEWABLE ENERGY GENERATION ABSORPTION 5.1 WIND ENERGY GENERATION FACTS MONTHLY WIND ENERGY GENERATION IN MUS Wind energy integrated in Gujarat Power System (Last 5 years) Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar MONTH WISE MAXIMUM WIND ENERGY GENERATION IN MW Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 11

20 0 to 1 1 to 2 2 to 3 3 to 4 4 to 5 5 to 6 6 to 7 7 to 8 8 to 9 9 to to to to to to to to to to to to to to to 24 Annual Report MONTH WISE MAXIMUM WIND ENERGY GENERATION IN MUS Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar HOURLY WIND ENERGY INJECTION TREND DURING THE YEAR Less than 500 MWH More than 500 MWH and less than 1000 MWH More than 1000 MWH and less than 1500 MWH From the above, it is observed that the wind energy injection during 09:00 Hrs. to 12:00 Hrs. was quite less, whereas during 16:00 Hrs. to 18:00 Hrs, it was on higher side. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 12

21 Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Annual Report MAXIMUM VARIATION IN WIND ENERGY GENERATION IN MUS ON TWO CONSECUTIVE DAYS ( MUs) ( MUs) ( MUs) ( MUs) 5.2 SOLAR ENERGY GENERATION FACTS MONTH WISE SOLAR ENERGY GENERATION IN MUS Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Solar energy in MUs State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 13

22 8 T O 9 9 T O T O T O T O T O T O T O T O Annual Report MONTH WISE MAXIMUM SOLAR ENERGY GENERATION IN A DAY IN MWH Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar MONTH WISE MAXIMUM SOLAR ENERGY GENERATION IN A DAY IN MUS Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar HOURLY SOLAR ENERGY GENERATION PATTERN DURING THE FY Less than 250 MWH More than 250 MWH & less than 500 MWH Greater than 500 MWH HOURS State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 14

23 5.2.5 TYPICAL SOLAR GENERATION CAPTURED Maximum Solar energy received in a day, Maximum variation in solar energy in a two consecutive days, Minimum Solar energy in a day (Max Solar energy received MUs), (4.64 MUs) (3.87 MUs) (2.75 MUs) (1.63 MUs) (Min Solar energy received MUs) Hrs Hrs Hrs Hrs Hrs Hrs Hrs Hrs Hrs Hrs Hrs Hrs Hrs Hrs Hrs. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 15

24 Annual Report DISCOM-WISE DEMAND FACTS 6.1 DISCOM WISE ENERGY CATERED DISCOM WISE ENERGY SUPPLIED IN MUS DURING LAST 7 YEARS PGVCL UGVCL MGVCL DGVCL SE CO AE CO Energy supplied by Discoms during PGVCL UGVCL MGVCL DGVCL TPSEC TPAEC 6.2 CATEGORY WISE ENERGY SUPPLIED IN MUS BY STATE DISCOMS JGY URB/TWN AGR IND Category wise energy supplied IND, 35098, 42% JGY, 12643, 15% URB / TWN, 13607, 17% AGR, 21789, 26% State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 16

25 Annual Report DISCOM WISE CATEGORY WISE ENERGY SUPPLIED IN MUS PGVCL JGY PGVCL URB PGVCL AG PGVCL IND UGVCL JGY UGVCL URB UGVCL AG UGVCL IND PGVCL UGVCL DGVCL JGY DGVCL URB DGVCL AG DGVCL IND MGVCL JGY MGVCL URB MGVCL AG MGVCL IND DGVCL MGVCL State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 17

26 6.4 MONTH - WISE CATEGORY - WISE ENERGY SUPPLIED IN MUS: JAN FEB MAR APR MAY JUN JUL JAN FEB MAR APR MAY JUN JUL DEC AUG DEC AUG NOV SEP NOV SEP OCT OCT JGY JGY JGY JGY JGY Urban Urban Urban Urban Urban MAR APR MAY MAR APR MAY FEB JUN FEB JUN JAN 0 JUL JAN 0 JUL DEC AUG DEC AUG NOV SEP OCT Agriculture Agriculture Agriculture Agriculture Agriculture NOV SEP OCT Industrial Industrial Industrial Industrial Industrial State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 18

27 7. VOLTAGE PROFILE STATISTICS AT IMPORTANT NODES 400 KV Kasor Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV KV Asoj Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV KV Jetpur Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV KV Amreli Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 19

28 400 KV Hadala Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV KV Chorania Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV KV Vadavi Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV KV Soja Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV KV Kansari Month Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar No. of days when bus voltage remained > 420 KV < 380 KV Max KV Min KV State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 20

29 Annual Report N O. D A Y S W H E N VOLTAGE R E M A I N E D M O R E T H A N K V K A S O R A S O J J E T P U R A M R E L I H A D A L A C H O R A N I A S O J A V A D A V I K A N S A R I Remark: SLDC had put up its best efforts to curb over voltage at 400 KV nodes. As a result, no. of days when voltage crossed its value (420 KV) had been reduced considerably at Kasor, Amreli & Chorania S/S. Even though in north Gujarat and at Asoj S/S, voltage remained high during the year. It might be due to less MVAR absorption support from WTPS, less schedule to WTPS units, light loading on newly commissioned 400 KV APL Kansari & 400 KV Varsana Kansari line and due to presence of 765 KV Vadodara. Also, there was unexpected rain in Oct 16. During high agriculture demand, low voltage had noticed in following 220 KV substations might be due to non-working / partial working of existing capacitor banks; South Gujarat area North Gujarat area Saurashtra area Bhilad Dhansura Vartej, Sagapara Navsari Chikhli Savarkundla Dhokadava, Timdi Keshod, Shapur Kangasiyali, Naghedi The additional capacitor bank or any other suitable measures shall be planned even though existing capacitor banks are in working condition to improve voltage profile. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 21

30 Hz Annual Report FREQUENCY PROFILE STATISTICS 8.1 MONTHLY AVERAGE FREQUENCY TREND FOR LAST THREE FINANCIAL YEARS Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Remark: The average frequency profile improved significantly. It remained in the range of Hz Hz during Year Whereas, it was in the range of Hz Hz during Year MONTHLY FREQUENCY TREND % of time block when frequency remained between Hz to 49.90Hz April May June July Aug Sept Oct Nov Dec Jan Feb Mar % of time block when frequency remained between Hz to 50.05Hz April May June July Aug Sept Oct Nov Dec Jan Feb Mar State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 22

31 <49.90, 59, 88 <49.90, 89, 108 > 50.05, 53, 158 > 50.05, 69, 129 > 50.05, 73, 121 > 50.05, 88, 129 Annual Report Frequency stastics in each time block of the Year % 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% <49.90 >=49.90 AND <=50.05 > Remark: 1. In bock No. 53, 69, 73 & 88, the frequency remained more than Hz most of the times. 2. In block No. 37,75, 82, 88 & 89, the system frequency remained below Hz for 15-30% of time throughout the year. 3. From block No. 88 to 89 daily, there were sudden change in frequency. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 23

32 9. GENERATION CAPACITY ADDITION /DECOMMISSIONED Capacity Addition during FY Sl. Unit Capacity (MW) GUVNL Share (MW) Date of COD 1 GSEG Expansion* DGBPS Unit No. 3* BECL Unit No Mauda Stage II Unit No BECL Unit No Wind Solar 214 Total 2974 Total GUVNL Share of Conventional 1374 *Dhuvaran Stage 3 (376.1 MW) & GSEG Expansion project (351 MW) have been considered for bare minimum fixed cost w.e.f & respectively vide GUVNL Letter No. GUVNL / COM / CFM(IPP)/SLDC/319 dated Decommissioning of Capacity during FY Sl. Unit Capacity (MW) GUVNL Share (MW) De-commissioning From 1 EPOL, Hazira GIPCL Stage - II GTPS Unit No GTPS Unit No UGPP Stage Total Capacity Decommissioned 840 State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 24

33 10. GRID EXPANSION EHV LINES ADDED IN GUJARAT GRID DURING YEAR Sr. No Name of line / Equipment 400 KV Kosamba - Jhanor line (Interconnection of 400 KV Ukai - Kosamba line No. 2 with 400 KV Jhanor - Kosamba line No. 1) 400 KV Ukai - Navsari (PG) line (Interconnection of 400 KV Ukai - Kosamba line No. 2 with 400 KV Jhanor - Kosamba line No. 1) 220 KV Kosamba - Ichhapore line & 220 KV GSEG - Essar line (Interconnection between one circuit of 220 KV GSEG - Kosamba and 220 KV Essar - Ichhapore line) Date of Commissioning KV GPPC - Sintex (Rajula) /220 KV, 315 MVA ICT No. 3 at Kasor KV Ichhapore - Sachin line (Interconnection of 220 KV Ichhapore -Essar line with 220 KV Essar - Sachin line No. 1) KV GSEG -Sachin line (Interconnection of 220 KV GSEG -Essar line with 220 KV Essar - Sachin line No. 2) KV D/C Visavadar - Timdi line KV Dhokadava - Sintex line KV D/C Dhokadava - GPPC line KV Vikram - Padavla line KV Padavla - Paliyad line /66 KV 50MVA Tr-1 Padavla /220 KV, 500 MVA ICT at UTPS (Augmentation from 315 MVA to 500 MVA) KV Bechraji - Maruti line No KV Bechraji - Maruti line No KV Mitha - Bechraji line No KV Mitha - Bechraji line no /132 KV, 150 MVA Trf - 2 Botad /132 KV, 150 MVA ICT - 2 Gondal (Augmentation from 100 MVA to 150 MVA) /220 KV, 500 MVA ICT 4 Kosamba /132 KV, 150 MVA ICT - 3 Gondal (Augmentation from 100 MVA to 150 MVA) KV Charanka - Veluda line No KV Charanka - Veluda Line No KV D/C Achhalia Tilakwada line /132 KV, 100 MVA ICT - 2 Bhatia /220 KV, 500 MVA ICT - 4 Amreli /132 KV, 150 MVA ICT - 2 Jamnagar (Augmentation from 100 MVA to 150 MVA) KV Sadla - Maruti WF line No KV Sartanpar - Vaghasiya line KV Botad - Parabdi WWIL line No /132 KV, 100 MVA ICT - 2 Sartanpar KV D/C Amreli - Visavadar line State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 25

34 11. MAJOR INCIDENTS Sr. No. Date PS / Substation affected Summary Load loss Gen loss (MW) (MW) :47 Hrs 220 KV Shapur S/S Prior to incident, the outage of 220/66 KV, 100 MVA Trf No. 1 was taken from 08:35 Hrs on for OLTC overhauling work. At 14:47, 220/66 KV, 100 MVA Trf No. 2 and 220/132 KV, 100 MVA Trf tripped at Shapur S/S due to activation TRSM3 96 relay There was load loss of about 62 MW :00 Hrs OPGS PS Prior to occurrence, there was a generation of 241 MW at OPGS ( Unit No. 1 was running on 114 MW & No. 2 on 227 MW). At 14:01 Hrs, 220 KV Varsana - OPGS line No. 1 tripped (OPGS end: Z1 B-Y, 4.0 KM. Varsana end:z2 R-Y, 50.1 KM, 1.9 KA). At the same time, 220 KV Varsana - OPGS line No. 2 tripped (OPGS end: Z3 Y-B. Varsana end: Z1 B-E, 50.8 KM, 1.86 KA). It led to black out at OPGS power Station. A tree found in induction zone between location No There was generation loss of 241 MW :04 Hrs. 400 KV Asoj S/S The R- ph. CT of 400 KV Asoj - Kosamba line fired. It led to tripping of 400 KV bus - 1. All elements connected to 400 KV bus -1 (Chorania line No. 1, Vadodara line No. 1, SSP line, 400/220 KV, 500 MVA ICT - 1, 400/220 KV, 315 MVA ICT - 3) along with bus coupler tripped. After isolating Asoj - Kosamba line, 400 KV bus - 1 was charged through bus coupler 02:49 Hrs. Thereafter, all elements were taken in service one by one. 0 0 However, there was no generation / load loss :40 Hrs. 220 KV Halvad S/S At 05:40 Hrs., 220 KV Halvad - Dhrangadhra line No. 2 which was on 220 KV Bus -B tripped (Halvad end: Z-I, Y-B Ph. 9.9 Km, 1.92 KA Dhrangadhra end: B Ph. Trip, Km, 1 KA). At the same time, B - ph. flyover string of 220/66, KV, 160 MVA Trf No. 1 bay flashed over. It led to bus fault on 220 KV Bus - A. All elements connected to 220 KV Bus A (Mansar line No. 1, Sartanpar line No. 2, Dhrangadhra line No. 1 ) tripped. 0 0 However, there was no generation / load loss. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 26

35 :07 Hrs.& 22:57 Hrs. WTPS All WTPS units were on bar. 400 KV WTPS - Dehgam line tripped at 22:07:55 Hrs on R- ph. to earth fault. The auto reclose had been operated, but again line tripped at 22:07:56 Hrs. At the same time, fire took place in 400 KV R - ph. CT of CT-11 bay (Tie bay between Dehgam line & GT of Unit No. 6) towards GT bay of unit No. 6 and it busted. It led to tripping of all breakers connected to 400 KV Bus 2 and unit No. 6 (running at 208 MW). Also, there was damage found in 400 KV B-ph CT of CT-15 bay i.e. tie bay (middle bay) between GT-7 & Soja line bay. There was heavy oil leakage found in CT and oil completely drained out Just after within few seconds, 400 KV WTPS Soja line tripped. It led to tripping of WTPS Unit No. 7 (running at 206 MW) due to evacuation constraint. Before exercising restoration of 400 KV Bus 2, 400 KV B-ph CT of CT 1 bay (ICT bay) got fired at 22:57 Hrs. It led to tripping of ICT and Unit No. 4 (running at 211 MW) due to evacuation constraint. There was a generation loss of 627 MW :58 Hrs. ALTPS & KLTPS Prior to incident, all Units of KLTPS TPS with total generation of 216 MW and all Units of ALTPS with total generation of 168 MW were on bar. 220 KV KLTPS - Kukma line No. 2 was made off at 09:00 Hrs. under R&M Work. At 16:45 Hrs., 220 KV KLTPS - Kukma line No. 1 tripped due to accident occurred while removing vibration damper at location No. 364 (S) on 220 KV KLTPS - Kukma line No. 2. At the same time 220 KV ALTPS - Nakhatrana line No. 1 tripped from ALTPS end on SOTF. thereafter at 16:56 Hrs., 220 KV KLTPS - Nakhatrana line No. 1 tripped from both ends (At Location No. 58 (T), conductor found broken) and 220 KV KLTPS - Nakhatrana line No. 2 tripped from KLTPS end only (Only breaker tripped. No relay indication was there). Only one line i.e. 220 KV ALTPS - Nakhatrana line No. 2 remained available for evacuation of ALTPS & KLTPS generation At 16:58 Hrs., 220 KV ALTPS - Nakhatrana line No. 2 tripped at ALTPS end only (R - Ph. Breaker Pole problem at ALTPS). Simultaneously, 220 KV KLTPS-ALTPS line No.1 & 2 tripped on Under-Voltage from ALTPS end. It led to black out at ALTPS & KLTPS. There was generation loss of 384 MW. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 27

36 :57 Hrs. 220 KV Tebhada WF Pooling station At 20:57 Hrs., the 33 KV feeder No. 13 tripped due to one insulator string flashover. It led to severe voltage dip at Tebhada S/S. It led to temporary disconnection of all WTG connected to pooling station There was wind generation loss of 219 MW for short duration for about three to four minutes :45 Hrs. 220 KV Vagra S/S The weather was very heavy humid and heavy wind there at the time of incident. At 21:45 Hrs., one insulator string of double tension string insulator of Y- ph. fly over bus of 220 KV Vagra - Dahej line bay flashed over. It led to activation of bus bar protection Zone 1 scheme. As a result, all elements connected to 220 KV Bus - 1 (220 KV Bus Coupler, 220 KV Dahej, 220 KV RVNL-01 and 220/66, KV 50 MVA Trf -01) tripped. 0 0 However, there was no load loss :45 Hrs. 220 KV Vagra S/S The weather was very heavy humid and heavy wind there at the time of incident. At 04:45 hrs. one insulator string of double tension string insulator of B- ph. fly over bus of 220 KV Vagra - Haldarva line bay flashed over. It led to activation of bus bar protection Zone -2. As a result, all elements connected to 220 KV Bus - 2 (220 KV Bus Coupler, 220 KV Haldarva line 220 KV RVNL line No. 2 and 220/66, KV 50 MVA Trf -1) tripped There was 20 MW load loss :20 Hrs. ALTPS Prior to tripping, ALTPS Unit No. 2 was on bar with 95 MW generation. 220 KV ALTPS - Nakhatrana line No. 1 tripped on Z1 B ph. to E, 1.5 Km from ALTPS end only. At the same time, 220 KV ALTPS - Nakhatrana line No. 2 tripped from ALTPS end. Also, 220 KV KLTPS - ALTPS line No. 1 & 2 tripped. It led to black out at ALTPS There was generation loss of 95 MW :32 Hrs. ALTPS There was heavy chattering in switch yard at ALTPS. All elements connected to 220 KV Bus A & Bus B tripped. It led to tripping of all elements connected to ALTPS There was generation loss of 92 MW (ALTPS Unit No. 2 was running at 92 MW). State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 28

37 :50 Hrs. 220 KV Vagra S/S The weather was very heavy humid. There was heavy chattering in switch yard especially on bus PT bay. It led tripping of 220 KV Bus - 2. As a result all elements connected to 220 KV Bus - 2 (220 KV Bus Coupler, 220 KV Haldarva line 220 KV RVNL line No. 1 and 220/66, KV 50 MVA Trf -1) There was 22 MW load loss :14 Hrs KLTPS At 18:14 Hrs, R- ph. conductor of 220 KV Panandhro - Kukma line No. 1 snapped and dropped down on 220 KV Bus - 1. As a result, bus fault occurred on 220 KV bus-1 and busbar protection activated at KLTPS. It led to tripping of all elements (GT - 1, GT - 2, 220 KV Nakhatrana line No. 1, 220 KV ALTPS line No. 1) connected to 220 KV Bus There was a generation loss of 136 MW :10 Hrs 132 KV Gotri S/S At 14:10 Hrs, 132/66 KV, 100 MVA Trf No. 1 & 4 and 132/66 KV, 40 MVA Trf No. 2 tripped from LV side only on B - ph. O/C due to thin piece of metal wire fallen down from beak of flying bird on B ph. of LV side isolator of Trf No There was load loss of around 130 MW for just few minutes :45 Hrs Pirana (PG) & Pirana (T) and df/dt operation at various S/S. At 19:45 Hrs at Pirana (PG) S/S, there were simultaneous tripping of multiple elements occurred at 19:45 Hrs due to inclement weather conditions. It was observed that external flashover had occurred across Y phase CVT of 400 KV Vadodara - Pirana line No. 2 and it extended to Wave trap of R phase. The fault persisted for about 500 ms At the same time, 400 KV Pirana(PG) - Pirana(TPL) line No. 2 from Torrent end and 132 KV D/C Pirana (TPL) - Vinzol line tripped. It led to 200 MW load loss at Pirana (TPL) S/S. Also, the df/dt relay operated at 220 KV Tharad, Jangral, Radhanpur, Kansari, Sankhari & Kim S/S. There was load relief of about 270 MW due to df/dt operation. There was load loss of about 470 MW :50 Hrs. 132 KV Bhatia S/S 132 KV Sikka -Bhatia line tripped at 7:45 Hrs. Thereafter within few minutes at 7:50 Hrs, 132 KV Bhatia - Khambhalia line No 1 & 2 tripped There was 70 MW wind generation and 21 MW load loss. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 29

38 :25 Hrs. OPGS The connectivity of OPGS Plant is extended to 400 KV network via 400/220 KV, 315 MVA ICT No. 3 at Varsana S/S. At 06:25 Hrs, 400/220 KV, 315 MVA ICT No. 3 at Varsana tripped on REF relay There was generation loss of 203 MW at OPGS :29 Hrs. 400 KV Varsana S/S 400 KV Bus - 1 at Varsana S/S tripped due to bus bar protection operated. At the same time, 400/220 KV, 315 MVA ICT No. 3 at Varsana tripped on REF relay. As connectivity of OPGS Plant is extended to 400 KV network via 400/220 KV, 315 MVA ICT No. 3 at Varsana, the blackout occurred at OPGS There was 88 MW generation loss :50 Hrs. 400 KV Varsana S/S Prior to disturbance, 400 KV Bus 1 was under forced shutdown. At 21:50 Hrs, 400 KV Bus - 2 at Varsana S/S tripped due to bus bar protection operated and it leads to tripping of all elements connected with bus There was 80 MW load loss :56 Hrs. 220 KV Jamanwada WF Pooling Station At 13:56 Hrs., 220KV Jamanwada - Varsana line tripped. At that time, 220kV Jamanwada - Ukheda line was in PF. There was 40 MW wind generation loss :37 Hrs. CGPL Prior to occurrence, four units of CGPL were on bar and both 400 KV buses at Varsana S/S were out due to tripping. The test charge of 400 KV Bhachau - Varsana line No. 1 from Bhachau end was taken at 2:37 Hrs. At that time, all EHV lines connected to CGPL tripped. It led to tripping of CGPL Unit No. 10, 30, 40 and 50 on over speed There was 2820 MW generation loss at CGPL :02 Hrs. 220 KV Limbdi S/S At 17:02 Hrs, 66KV Limbdi - Surendranagar line No. 2 tripped. At 17:07 Hrs., the test charge was taken, but due to reflected fault on line, 132/66 KV, Trf. No. 1, 2 & 3 tripped from LV side There was 66 MW load loss. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 30

39 :47 Hrs 400 KV Varsana S/S Prior to occurrence, 400 KV Varsana - Kansari line was on 400 KV Bus - 2. The shutdown was planned for attending 89 - A bus isolator of 400 KV Varsana - Kansari line by transferring said element on transfer bus. While taking 400 KV Varsana - Kansari line on transfer bus, elements connected to 400 KV Bus - A (400/220 KV 315 MVA ICT No. 1 & 3, 400 KV Varsana - Hadala line, 400 KV Bus coupler, 400 KV 50 MVAR reactor) tripped on activation of LBB protection. The 400/220 KV, 315 MVA ICT No. 3 is radially connected with OPGS generation plant (2 x 150 MW) through 220 KV D/C Varsana - OPGS line. Hence, there was generation loss of around 210 MW The 400/220 KV, 315 MVA ICT No. 3 was charged on 400 KV Bus - B at 13:02 Hrs and power supply was extended to OPGS. 400 KV Bus - A was charged through 400 KV Bus coupler at 14:03 Hrs :25 Hrs 220 KV Halvad S/S At 08:25 Hrs, Zone - 2 bus bar protection operated at Halvad S/S due to failure of 220 KV R ph. PT of 220 KV Bus-2. It led to tripping of all elements connected to 220 KV Bus - B (220 KV Mansar - Halvad line No. 2, 220 KV Halvad - Dhrangadhra line No. 2, 220 KV Halvad - Sartanpar line No. 2 and 220/66 KV, 160 MVA Trf No. 1). 0 0 There was no generation / load loss in system :30 Hrs 220 KV Halvad S/S There was saline atmosphere with drizzling rain in surrounding area. The 220 KV B ph. post insulator of 220/66 KV, 160 MVA Trf No 1 bay near circuit breaker flashed over at 04:30 Hrs. It led to tripping of all elements on activation of bus bar protection for both buses There was load loss of 19 MW :05 Hrs 132 KV Vikram S/S At 06:05 Hrs, both 66 KV Vikram - Tramba line 1 and 2 tripped. At the same time, all 132/66 KV transformers at Vikram S/S tripped from LV side There was load loss of 54 MW :30 Hrs. 220 KV Sadodar WF pooling station At 14:30 Hrs, all 33 KV CTs of 33 KV Fulnath - 2 feeder blasted. It led to tripping of 220 KV D/C Motipaneli - Sadodar line from Motipaneli end only There was 70 MW wind generation loss. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 31

40 :20 Hrs. Akrimota PS 220 KV ALTPS - KLTPS line No. 1 was made off at 08:55 hours for attend hot point at KLTPS end. At 09:20 Hrs, 220 KV ALTPS - KLTPS line No. 2 tripped (Relay at KLTPS end: Z1 R - ph Km, 4.9 KA Relay at ALTPS end: Z1 R - ph. SOTF, 13.5 Km). The R ph. jumper found open at location No. 3. It led to tripping of all elements connected to 220 KV Bus B along with Buscoupler at ALTPS There was 86 MW generation (ALTPS Unit No. 2 was running at 86 MW and connected with Bus - B) loss :42 Hrs 220 KV Jamanwada WF pooling station At 13:42 Hrs, 220 KV Jamanwada - Varsana & 220 KV Jamanwada - Ukheda line tripped on over voltage from Jamanwada end only. There was 72 MW wind generation loss :45 Hrs 220 KV Sadodar WF pooling station At 00:45 Hrs, 220 KV D/C Sadodar Motipaneli line tripped from both end. There was 82 MW wind generation loss :22 Hrs 400 KV Amreli S/S At 09:22 Hrs, 400 KV B Ph. breaker pole of 400 KV 125 MVAR reactor flashed over. It led to activation of Bus bar Zone - 1 protection. As a result, all elements connected to 400 KV Bus - 1 (400 KV Amreli - Chorania line, 400 KV Amreli - Jetpur line No. 2, 400/220 KV, 315 MVA ICT-3) tripped. 0 0 However, there was no generation / load loss :10 Hrs 220 KV Halvad S/S There was planned shutdown of 220/66 KV, 160 MVA Trf No. 1. At 12:10 hrs, heavy sparking observed on LV side of 220/66 KV, 160 MVA Trf No. 2 bus-a isolator T-clamp R & B phase jumpers. So, it was hand tripped from LV side due to security reason There was 78 MW load loss :45 Hrs. 220 KV Gondal S/S At 14:45 Hrs, all 132/66 KV transformers tripped on over current from LV side There was 136 MW load loss. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 32

41 :37 Hrs 400 KV Jetpur S/S The special load shedding scheme (SPS) is armed to restrict over loading at Jetpur ICT. When loading on any 400/220 KV, 315 MVA ICT at Jetpur reaches to 431 Amp and remains for 5 sec, SPS will activate and It will trip all 66 KV feeders connected to Jetpur S/S At 05:17 Hrs, the outage of 400/220 KV, 315 MVA ICT No. 3 was taken for carry out off line tap change operation. At 05:37 Hrs, SPS initiated and tripped all 66 KV feeders connected to 66 KV bus of 400 KV Jetpur S/S. There was load loss of around 120 MW :05 Hrs 400 KV Jetpur S/S There was heavy rain in surrounding area. 400 KV side Zone -1 bus bar protection operated at 03:05 Hrs. It led to tripping of all elements connected to 400 KV Bus - 1 (400/220 KV, 315 MVA ICT - 1, 400/220 KV, 500 MVA ICT - 4, 400 KV Amreli - Jetpur line No. 1, 400 KV CGPL - Jetpur line No. 1, 400 KV Bus coupler). During detail observation, Y ph. centre break isolator of 400 KV 50 MVAR bus reactor bay found open. 0 0 However, there was no generation / load loss in system :31 Hrs Sikka PS There is an one and half breaker scheme arrangement at 220 KV switch yard Sikka TPS. Prior to occurrence, both STPS Unit No. 3 and 4 were on bar. The generation was about 385 MW As per the planning, the testing of distance protection scheme of newly erected bay for 220 KV Jamnagar line and 220 KV Jetpur line was being carried out. Also, the tie breaker of GT 3 & 4 bay were kept open. At 14:31 Hrs, protection system mal operated while testing. All elements connected to 220 KV Bus - 2 tripped on activation of busbar protection scheme. As a result, there was 385 MW generation loss at STPS :07 Hrs 220 KV Gavasad S/S At 04:55 Hrs, 220 KV Bus Zone - 1 protection operated. It led to tripping of all elements connected to 220 KV Bus - 1 (SLPP line No. 1, Kasor line No. 1, Kosamba line, Karjan line, 220/66 KV, 50 MVA Trf No. 1 & 3). At the same time, 220/66 KV, 50 MVA Trf No. 2 tripped on over current. The suspected B - ph. pilot string of Trf No. 3 bay 220 KV side replaced There was 74 MW load loss. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 33

42 :50 Hrs Sikka TPS At 12:50 Hrs, B - ph top flyover jumper of suspension insulator of 132 KV Sikka - RPL line bay broken and fallen down on 132 KV Bus - B. It led to bus fault at Sikka S/S. All elements connected to both 132 KV buses tripped. Also, there was heavy deep in voltage. It led to tripping of all auxiliaries of Unit No. 3. As a result, Unit No. 3 tripped of low forward power protection There was generation loss of 190 MW :45 Hrs 220 KV Halvad S/S At 05:15 Hrs, 220 KV R- ph. CT of 220 KV Halvad - Dhrangadhra line No. 2 flashed over. As a result, 220 KV Bus Zone -2 protection operated. It led to tripping of all elements connected to 220 KV Bus Later on at 05:45 Hrs, 220 KV R - ph CT of 220 KV Halvad - Dhrangadhra line No. 1 flashed over. As a result, 220 KV Bus zone -1 protection operated. It led to tripping of all elements connected to 220 KV Bus 1. It led to complete blackout at Halvad S/S. There was 50 MW load loss :20 Hrs 220 KV Charadava S/S At 10:20 Hrs, 220/66 KV, 100 MVA Trf No. 1 and 2 tripped simultaneously due to mal-operation of protection scheme while testing There was 48 MW load loss :47 Hrs 220 KV Halvad S/S At 05:47 Hrs, 220 KV Y ph. breaker pole of 220 KV Halvad - Dhrangadhra line No. 1 flashed over. As a result, 220 KV Bus zone - A protection operated. It led to tripping of all elements connected to 220 KV Bus However, there was no generation / load loss :45 Hrs 220 KV Sagapara S/S At 10:45 Hrs, 66 KV Sagapara - Devaliya (Tap to Thadach) line tripped from Devaliya end only. The line breaker did not trip at Sagapara end. It led to tripping of 220/66 KV, 100 MVA Trf 1 & 2 from LV side and Trf No. 3 from both side There was 110 MW load loss in system :40 Hrs 220 KV Charanka S/S At 09:40 Hrs, 220 KV Charanka - Jangral line No. 1 & 2 tripped from Jangral end only on Z3, RYB There was 60 MW Solar generation loss :14 Hrs 220 KV Charanka S/S At 12:14 Hrs, 220 KV Charanka - Jangral line no. 1 & 2 tripped from Jangral end only on Z3, RYB There was 155 MW Solar generation loss. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 34

43 :05 Hrs 220 KV Halvad S/S Prior to incident, 220/66 KV, 160 MVA Trf No. 2 was under planned shutdown. There was planning of 66 KV Bus - B shutdown. At 10:05 Hrs, while changing 66KV Bus Isolator of 220/66KV 160 MVA TR-1 from 66 KV Bus - B to 66 KV Bus - A, a heavy spark occurred. It led to tripping of 66 KV Bus coupler as well as 220/66KV, 160 MVA Trf No. 1 from LV side. As a result, there was blackout at Halvad S/S There was 73 MW load loss :12 Hrs 132 KV Wanakaner S/S Prior to incident, 132 KV Jamnagar - Wankaner line was made off from Wankaner end for load control on 220/132 KV ICTs at Sikka. There was planned shutdown of 132/66 KV, 50 MVA Trf No. 2. While opening of 132 KV Bus isolator of Transformer at 12:12 hrs, R- ph. post insulator of bus isolator broken down from bottom and it came down in induction zone of 132 KV bus. As a result, 132 KV Wankaner - Limbdi line tripped on Z-2 R ph. OC at Wankaner end & on Zone-2 at Limbdi end. Simultaneously, 132kV Wankaner - Sitagadh line tripped from Sitagadh end on Zone There was of 81 MW load loss :30 Hrs 220 KV Savarkundla S/S At 17:30 hrs, 220 KV Savarkundla-Amreli line No. 2 tripped from Amreli end on PT fuse fail. It led to activation of SPS provided at Savarkundla S/S. As a result, 7 (Seven Nos.) 66 KV feeders tripped There was load loss of around 48 MW :58 Hrs 220 KV Jambuva S/S Prior to occurrence, 220 KV Jambuva Haldarva line was in shock charge condition from 220 KV Haldarva S/S end under load control. On at 15:58 hours, R phase CT of 220 KV Jambuva - Haldarva line flashed over at Jambuva S/S. It led to tripping of all EHV elements connected to 220 KV Bus I and Bus II on activation of bus bar protection scheme at 220 KV Jambuva S/S. However, 132 KV bus supply at Jambuva S/S survived on Asoj system There was load loss of 22 MW :15 Hrs 220 KV Vav S/S At 17:15 Hrs, all 220/66 KV Transformers tripped due to hazardous blast occurred in 66 KV Capacitor Bank. However, all 220 KV lines remained live There was load loss of 306 MW. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 35

44 12. MONTHLY GETCO NETWORK LOSSES (%) Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar Apr May June July Aug Sept Oct Nov Dec Jan Feb Mar State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 36

45 13. ENERGY ACCOUNTING & SETTLEMENT AND STOA DETAILS 13.1 ABT METERS REGISTERED FOR DATA PROCESSING AT SLDC No. of ABT Meters Registered As on As on NOS. OF ACTIVE UI POOL MEMBERS IN UI POOL ACCOUNT OF SLDC No. of active UI Pool Members in UI Pool account of SLDC As on As on USERS REGISTERED UNDER REC MECHANISM No. of Users registered under REC Mechanism As on As on SHORT TERM OPEN ACCESS APPLICATIONS PROCESSED Short Term Open Access Applications Statistics Year No. of Application Received No. of Application Approved No. of Application Rejected State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 37

46 14. SCADA & IT UPDATES 14.1 DATA ACQUISITION UPDATES No of RTUs RTU Category As on As on IT UPDATES Generating station and Substation Level Solar OA consumer Wind Farm Pooling Stn a. New SCADA system (Alstom make) has been commissioned at SLDC Gotri, Sub - SLDC Jambuva, Sub - SLDC Jetpur, Sub SLDC Gandhinagar. Also, the backup control centre has been established and functioning with NEW SCADA system at Sub SLDC Gandhinagar. In new SCADA system additional 8 nos of VPS Screen provided for accommodating more display for efficient and better power system operation b. To ensure 100 % availability of real time data availability between various control centres following leased lines are provided. 1) Main Control centre Gotri Backup Control Centre Gandhinagar (10 Mbps-BSNL) 2) Main Control centre Gotri Sub SLDC Control Centre Gandhinagar (4 Mbps-BSNL, Airtel) 3) Main Control centre Gotri Sub SLDC Control Centre Jetpur (4 Mbps-BSNL, Airtel) 4) Main Control centre Gotri Sub SLDC Control Centre Jambuva (2 Mbps-BSNL) 5) Backup Control centre Gandhinagar Backup WRLDC Control Centre Delhi upto Dehgam PGCIL (6 Mbps-BSNL) 6) Backup Control centre Gandhinagar Sub SLDC Control Centre Jetpur (4 Mbps-BSNL, Airtel) 7) Backup Control centre Gandhinagar Sub SLDC Control Centre Jambuva (4 Mbps- BSNL, Airtel) c. SLDC has planned for replacement of old RTUs of GE due to obsolete technology. a. Cyber security monitoring has been ensured with the help of admin based Quick heal antivirus through Cyberoam Firewall for internet. b. SLDC Control room is equipped with WIFI facility for official communication and android based Samsung mobile instrument. c. Automatic Demand Management Scheme (ADMS) is implemented in all four State Distribution companies. ADMS Phase-II is under planning stage for implementation in 100 more Substations. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 38

47 d. The E-payment facility for online payment is made operational. e. SLDC is equipped with CCTV (PTZ & static) camera, additional 4 Nos of camera installed and made operationalized for more security purpose. Total 16 nos of CCTV cameras are working. f. SLDC is equipped with high speed scanners (5 Nos.) for providing faster and better services to the stake holders. g. The Gujarat network is modelled in PSS/E software. It is very much helpful for critical outage security assessment and to carry out studies for proposed network topology changes etc h. Video conferencing facility has been successfully working between WRLDC Mumbai and Gotri SLDC, Gandhinagar Backup-SLDC and Jetpur Sub-SLDC. i. Implementation of wind forecasting mechanism. j. Analytics Software 1) On Line Oscillation Mode Identification, 2) Hybrid State Estimator and 3) Dynamic Security Assessment from PMU data developed by IIT Bombay is implemented. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 39

48 SYSTEM ARCHITECTURE FOR INTEGRATION ON RENEWABLE ENERGY GENERATION DATA State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 40

49 15. FINANCIAL FACTS & FIGURES 15.1 AGGREGATE REVENUE REQUIREMENT FOR THE FY SLDC is filing its Aggregate Revenue Requirement (ARR) independently from the FY First ARR was filed in Jan 2010 and since then SLDC has not looked back and achieved new feats towards becoming financially self-reliant. A glimpse of the ARR for the FY is given below: Particulars Rs. In Lacs Approved by GERC Employee Cost Repairs & Maintenance Admin & General Expenses Interest on Working Capital RLDC Fees and Charges Charges for ULDC & Other related projects WAM Charges -- SCADA Upgradation Less : Other Income Operating Cost Budget (a) Depreciation Interest & Finance Charges Return on Equity Less : Expenses Capitalized -- Add : Provision for Tax Capital Cost Budget (b) Total Revenue Budget On the basis of the above, tariff rates decided by Hon ble GERC for SLDC are : SLDC Charges budget for the FY Approved by GERC 1 ARR Approved in the MYT Order for FY Rs./Lakh Less : Revenue Surplus approved in Truing-up for FY Rs./Lakh Total SLDC Charges Rs./Lakh Grid Connection Charges Rupees 10, State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 41

50 15.2 MAJOR FIGURES FOR THE FY As per GERC directive, SLDC got its Final Accounts audited from a Chartered Accountant from the FY SLDC is near to closing its financial books for the FY after which it will be presented before a Charted Accountant for Statutory Audit; however, some major unaudited figures for the FY are as below: Rs. in Lacs Particulars (Income) Amount Particulars (Expenses) Amount SLDC Charges Repairs & Maintenance* STOA Scheduling Employee Cost STOA Application Admin & General Expenses Miscellaneous Income Depreciation Finance Charges 7.53 Loss on Sale 1.34 Total Total * Including ULDC Charges The above figures are subject to provision entry of Terminal benefits such as Gratuity, Leave Encashment, Finance Charges and any rectification entry arising out of audit of the FY % 4% 10% 0% 23% Major Income 19% Major Expenses 23% SLDC Charges STOA Scheduling STOA Application Misc. Income 65% R & M Employee Cost A& G Depreciation Finance Charges Loss on Sale 48% State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 42

51 15.3 CAPEX PLAN OF SLDC A significant portion of SLDC cost arises because of the grid operations activities, which are to be carried out round-the-clock requiring adequate redundancy in resources to tide over contingencies. There is a heavy reliance on information technology with components having high obsolescence rate. A few of the applications (such as SCADA/EMS) are offered by a limited number of vendors with high cost. In view of revised role of State Load Despatch Centre after enactment of Electricity Act 2003, it is necessary to strengthen SLDC to meet forthcoming challenges for the coming years. Accordingly, Capital Expenditure (CAPEX) is planned for modernization of SLDC to strengthen and develop to meet all forthcoming challenges. CAPEX plan includes, projects mainly focused on system expansion, real time data requirements, installation & development of telemeter infrastructure, technological innovations and obsolescence & replacement of existing infrastructure, strengthening of existing data communication channels, billing & commercial centre development, system study and IT related infrastructure. SLDC CAPEX plan approved by Hon ble GERC for the FY is as follows : Sr. No. Particulars Approved in MYT (Rs. In Lacs) 1 Augmentation/ Upgradation of existing systems Strengthening of communication channels IT Infrastructure Office Equipment Additional Expenditure Total Capital Expenditure Upgradation Strengthening IT Infra Office Eqp. Additional State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 43

52 16. FUTURE OUTLOOK & NETWORK IMPROVEMENT A. Enhancing Transformation Capacity The need of augmentation to cater future load growth reliability is summarized as under: Particular Additional 400/220 KV, 500/315 MVA ICT requirement Augmentation to be planned at Substations Replacement of existing 220/132 KV, 100 MVA ICT with 150 MVA capacity Power Stations / Substations Ukai, WTPS, Kansari and Varsana (* for reliable evacuation of OPGS generation). Karamsad, Limdi, Jambuva and STPS B. Skewed despatch scenario in Central & South Gujarat Pocket Due to availability of substantial cheaper generation on 400 KV network, power flow through 400/220 KV ICTs has increased significantly. Major part of 220 KV EHV lines in South Gujarat always remained loaded throughout the year. Generation capacity of the order of 2500 MW, which otherwise was served to consumers at 220 KV / 132 KV level remains unutilized most of the time due to costly fuel (Gas). Hence, there are always severe constraints in Central & South Gujarat system. Particularly, 220 KV S/C Asoj - Jambuva, 220 KV D/C Kasor Karamsad line, 220 KV D/C Ukai - Mota, 220 KV D/C Jhanor Haldarva and 220 KV D/C Navsari (PG) Navsari (GETCO) lines remains critically loaded. After commissioning 400/220 KV, 500 MVA ICT No. 4 at Kosamba, augmentation of transformation capacity at Ukai and establishing few lines (400 KV Ukai - Dastan line, 400 KV Kosamba - Jhanor line, 220 KV GSEG Sachin line, 220 Ichhapore Sachin line), the system reliability has significantly improved. Also, it helps to evacuate power of UTPS Unit No. 6 smoothly. Also, following transmission schemes which are under execution in the area shall be expedited: Additional 400/220 KV, 500 MVA ICT at Ukai and WTPS LILO of 220 KV Haldarva Zaghadia line at NTPC Jhanor PS 220 KV D/C Navsari Bhestan line LILO of one circuit of 220 KV Vyankatpura - Achhalia line (under construction) at Waghodia S/S from crossing point of 220 KV Asoj - Waghodia and 220 KV Waghodia Jambuva line to have 2 nd circuit of 220 KV Asoj Jambuva line. 220 KV D/C Vyankatpura Vadodara (PG) line. Interconnection of 220 KV D/C GSEG - Mota line (under construction) with existing 220 KV Kosamba Utran line: State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 44

53 C. Reliability improvement suggestions for Saurashtra - Kutch and North Gujarat Power System operation: The following EHV lines / elements remains critically loaded in West Gujarat Power System: KV D/C Amreli Savarkundla line KV Jetpur - Visavadar line KV Jetpur - Shapur line KV Jetpur Gondal line KV Hadala Kangasiyali line KV Jasdan Paliad line (In high wind scenario) KV Nyara Vikram & 132 KV Nyara Vajadi line /132 KV ICTs at STPS After commissioning 400/220 KV, 500 MVA ICT No. 4 at Amreli, 220 kv D/C Amreli - Visavadar & 220 KV D/C Visavadar - Timdi line and augmentation of transformation capacity at Gondal and Jamnagar, the system reliability and voltage profile has significantly improved. However, the integration of following transmission schemes / projects would strengthen the Power System in Suarashtra area: Augmentation of ICT at STPS LILO of 220 KV Jetpur - Sardargadh line at 220 KV Shapur S/S LILO of 220 KV Jetpur - Jamnagar line No. 2 at STPS Interconnection of 220 KV S/C Nyara - Jetpur line with 220 KV D/C Kangasiyali - Kalavad (under construction) so as to have LILO of 220 KV Nyara - Jetpur line at Kangasiyali S/S. Interconnection at interception point of 132 KV Sikka - Bhomiavadar line with one circuit of 132 KV D/C Bhatia - Khambhalia line to have one additional circuit of 132 KV Sikka - Bhatia line and one circuit of 132 KV Khambhalia - Bhomiavadar line. The following EHV lines / elements remains critically loaded in North Gujarat Power System: KV Vadavi Chhatral line /220 KV, 315 MVA ICTs at Kansari KV Karamsad Nadiad line The commissioning of 4 th ICT at Kansari, LILO of 132 KV Dhuvaran - Vatva at Mahemdavad S/S will improve reliability of North Gujarat Power System. To restrict loading on 220 KV Vadavi - Chhatral line, one circuit of 220 KV Gandhinagar - Chhatral line shall be made LILO at Vadavi S/S. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 45

54 D. Emerging need to establish connectivity at 132 KV S/S Randeja of TPL: Presently, load of the Capital city of Gujarat is catered from 132 KV D/C Randeja - Sabarmati TPS (TP AE Co) line. The Generating capacity of 422 MW of TPL AE Co Sabarmati is connected to GETCO Sabarmati substation subsequently to Ranasan substation of GETCO through 132 KV D/C Sabarmati Ranasan line. Around 500 MW demand is cater with the generation of TPL AE Co and import of around 150 MW power from GETCO grid through KV D/C Sabarmati Ranasan line. The 132 KV D/C Ranasan Sabarmati line is passing through dense city area of Ahmedabad which is prone to tripping of the line. The tripping of any one circuit of 132 KV Ranasan - Sabarmati line or 132 KV Sabarmati - AE Co line or ICT at Ranasan S/S may lead generation loss of around 300 MW & load loss of around 450 to 500 MW in case of failure of islanding scheme installed at AE Co OR around 150 MW load loss on account of activation of islanding scheme. Therefore, it is utmost necessary to plan connectivity at Randeja S/S of TPL from 132 KV Chiloda S/S of GETCO to form ring system. It will definitely enhance reliability of power supply to capital city of Gujarat and VIP areas of Ahmedabad. E. Emerging need for enhancement of transformation capacity at Sugen: At TPL Sugen, there are three Nos. 400/220 KV, 315 MVA ICT in service to cater the load of Surat City (around 550 to 650 MW). To comply CEA reliability criteria (N-1-1) and to enhance reliability of power supply to Surat city, there is a need of 4th ICT at Sugen S/S. F. Establishment of pump mode operation at SSP: It is well known fact that the pump mode operation of hydro plant plays a vital role in Power System Operation. During high wind injection, it is utmost necessary to store energy in the form of hydro and for maintaining under drawl within the specified limit and to curb over voltage during off-peak system condition. Also, the storage of energy in off peak hours and utilizing it in peak hours will help to optimize the cost of electricity. As Gujarat is one of the Renewable Energy rich States having installation of 6500 MW with no balancing facility and flexibility, the establishment of pump mode operation at SSP is emerged as principal and long term requirement of secure, reliable, flexible and economical Power System operation of the State. There are mainly two parts involved in project: 1. Construction of Garudeshwar weir 2. Upgradation of RBPH Units. The issue of establishment of pump mode operation at SSP is being repeatedly taken up in WRPC (Western Regional Power Committee), CEA, Mumbai by this office. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 46

55 G. Re-establishing of pump mode operation at Kadana HPS: The reestablishment of pump mode operation at KHPS is emerging need of Gujarat power system as Gujarat is having sizable portfolio of renewables. It will extend flexibility of picking generation as well as providing load within few minutes to the system. GSECL should come out with strong action plan for the reestablishing pump mode operation in time bound period. GSECL may apply for funding from PSDF for the said work. SLDC will extend all cooperation for taken up proposal in PSDF. H. SCADA up-gradation with Back-up SLDC SLDC is equipped with SCADA system in which Remote Terminal Units (RTU) are placed at substations / generating stations. RTU sends analog data like Active power, Reactive power, Frequency, Voltage and Digital data like breakers and isolators status. The system also provides EMS package. The New Alstom (now GE system) has been installed and working satisfactorily. It has more advance features and enhanced EMS package. The Alstom E-terra network model is having following modules; Power System Model Update State Estimation (SE) Bus Load Forecast (BLF) Transmission Loss Sensitivity Factors (TLSF) Contingency Analysis (CA) Optimal Power Flow (OPF) Transmission Line / Corridor Capability Monitor (TCM) Short Circuit Analysis (SCA) Transient / Dynamic Stability Analysis. At present, hierarchy of the system operation is set as, three Sub SLDCs looking after individual area functions and SLDC for the State as a whole. Maintaining same hierarchy, a back-up SLDC at Sub SLDC Gandhinagar has been established and operationalized. The mock drill for power system operation from back up SLDC is being arranged at regular interval to take over real time system operation in case of any contingency arising at main SLDC. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 47

56 I. Analytics Software from PMU data for System operation: SLDC has implemented WAMS project for system operation. Under this project, 118 Nos. of PMUs have been installed at 25 locations and 1500 phasors data of 500 feeder bays are received at SLDC. PDC is commissioned at SLDC for visualization of PMU data in operation activity. It is very useful tool for angle relationship between electrical area and important substations to access the system strength and various other features like df/dt, voltage magnitude etc. It is becoming very useful tool for post event analysis and system calibration. The PMU data are being used to design the intelligent software for system operation work. SLDC has executed MOU with IIT-Bombay for developing following three Analytics software from PMU data for system operation work under Research and Development project. 1. Online oscillation stability mode identification 2. Hybrid State Estimator 3. Dynamic Security Assessment (DSA) At Present, first analytics i.e. online oscillation stability mode identification has been installed and put in service. It had been observed that the Gujarat Power System is having oscillation with higher damping i.e. more than 5. The 2nd analytics i.e. HSE is also commissioned. The third analytics i.e. DSA is developed and will be commissioned as HSE is stabilized as output of the HSE will be used as input to the DSA with voltage stability. Optimum utilization of these analytics for exercising supervision of Gujarat power system will be through very advance tool available in the world which will be very much useful for secure grid operation and increase the confidence of the system operator. J. Establishment of Renewable Energy Management Centre (REMC): Gujarat is established one of RE reach State of India. As on , the installed capacity of the State in Wind farms is 5318 MW and 1230 MW in Solar. Also, it has emerged as highest potential for development renewable energy generation because of 1600 Km long costal line. SLDC has identified the necessity of RE generation forecasting for safe and reliable grid operation. SLDC Gujarat & PGCIL had worked together for the pilot project on RE generation forecasting. After gaining the experience from pilot project, SLDC had initiated process for hiring services from RE generation forecasting service provider. The service provider is finalized now. SLDC is getting more accurate forecasting of RE generation. At present, SLDC is getting day ahead, real time and weekly wind generation forecast for State as whole through online web based application from service provider. For the said service, SLDC is providing various static and variable data through FTP access. In turn, FSP is providing forecast in State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 48

57 96 blocks on online web based application, & FTP access. SLDC is also fetching real time data from each RE pooling stations. SLDC is continuously monitoring real time trend with forecasted generation. It is being regularly utilised for system operation and better forecasting & analysis purpose. Further under guideline of Ministry of Power, Government of India, PGCIL has initiated development of establishment of full fledge REMC on behalf of seven Nos. RE rich State. Gujarat is one of the State participating in the development. K. LVRT protection for Wind & Solar generators in Western Region - Compliance to order of the Hon ble CERC in petition No. 420/MP/2014 The LVRT-term is capturing the ability of a wind turbine to stay connected to the grid throughout a short mains voltage drop. It is essential that a wind park stay online in order to prevent major blackouts whenever there is a sudden dip in voltage. Hon ble CERC in its order in petition No. 420/MP/2014 dated directed that: 1. LVRT should be implemented for all wind turbines commissioned before and connected to voltage level of 66 KV and above except for stall type WEGs and having installed capacity equal to or more than 500 KW. 2. The Solar generators whose bidding process has not yet commenced i.e. NIT has not yet been issued on date of CERC order shall take necessary steps to implement LVRT in their generating stations. With regard to monitoring of the installation and performance of LVRT installed in existing WTGs, Hon ble CERC directed SLDCs to prepare quarterly reports and submit to RPCs. RPCs are directed to validate the report and deficiency and non-compliance to the Commission in accordance with the Law. SLDC - Gujarat has taken up the matter with all RE developers. L. Phasing out thermal capacity which are noncompliant to New Environmental Norms (issued by MoEF&CC) to be implemented w.e.f. 7th December 2017 A committee was constituted by Ministry of Power; Govt. of India on for preparing a phasing plan for implementation of new environmental norms issued by MoEF&CC in December The first meeting of committee was held on It was decided that the concern RPC shall prepare phasing of implementation plan in consultation with concerned power utilities at State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 49

58 regional level and POSOCO considering the power supply position. It was opinion that units in which ESP retrofitting/upgrade is implemented should be allowed to run at least 5 years from the date of completion of work. The 2 nd meeting of committee was held on It was informed that ESP upgradation is require to meet new environmental norms regarding SPM. It is necessary that FGD (Flue Gas Desulphurization) to be installed to comply with new SOx emission norms. The thermal units which have space for FGD installation does not require ESP upgradation as effective SPM reduction would be possible by FGD apart from control of SOx emissions. The total installed capacity of Gujarat State is 27,057 MW as on Amongst total capacity, the share of thermal capacity is 13,938 MW. The older units does not have space for FGD installation. For provision of FGD, generators shall have to invest capital expenditure as well as their auxiliary consumption would also increase. Therefore, it needs principal approval of regulator as well as procurer as there may be hike in fixed as well as variable cost. The plant load factor will be adversely affected due to high variable cost. Even if 25 years lifespan of thermal unit would consider for phasing out due to non-compliant of new environment norms, than around 3500 MW capacity would likely to be phased out for only in Gujarat State. In such condition, majority of State thermal units will be phased out from System. The Gujarat State is usually dependent on thermal capacity to meet the demand and to integrate renewable energy generation and its variation. Also, the developments of Intra State as well as Inter State transmission system have been planned considering full dispatch from the thermal units for catering the system demand. There is a 1000 MW on an average demand rise every year. The rate of increase in thermal / gas capacity is very slow compared to demand rise. The power procurement by the Discoms and development and strengthening of transmission network against capacity to be phased out shall take considerable time horizon. M. 5th amendment of IEGC Regarding implementation thereof Hon ble CERC vide its order dated 12th April, 2017 has notified 5th amendment in IEGC principal regulation of IEGC (Indian Electricity Grid Code) It is become effective from 1st May, As per the 5th amendment of IEGC, all Coal/lignite based thermal generating unit s of 200 MW State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 50

59 and above, Open Cycle Gas Turbine/Combined Cycle generating stations having gas turbines of capacity more than 50 MW each and all hydro units of 25 MW and above, which are synchronized with the grid, irrespective of their ownership, shall have their governors in operation at all times. Open Cycle Gas Turbine/Combined Cycle generating stations having gas turbines of capacity more than 50 MW each shall have their governors in operation with effect from There should not be any reduction in generation in case of improvement in grid frequency to a level below Hz. (For example, if grid frequency changes from 49.9 to Hz, or from to Hz there shall not be any reduction in generation). For any fall in grid frequency, generation from the unit should increase as per generator droop up to a maximum of 5% of the generation subject to ceiling limit of 105% of the MCR of the unit having regard to machine capability. All coal/lignite based thermal generating unit s of 200 MW and above, Open Cycle Gas Turbine / Combined Cycle generating stations having gas turbines of more than 50 MW each and all hydro unit s of 25 MW and above operating at or up to 100% of their MCR shall have the capability of (and shall not in any way be prevented from) instantaneously picking up to 105%, 105% and 110% of their MCR, respectively, when the frequency falls suddenly. After an increase in generation as above, a generating unit may ramp back to the original level at a rate of about one percent (1%) per minute, in case continued operation at the increased level is not sustainable. Any generating unit not complying with the above requirements shall be kept in operation (synchronized with the Regional grid) only after obtaining the permission of RLDC. For the purpose of ensuring primary response, RLDCs/SLDCs shall not schedule the generating station or unit (s) thereof beyond exbus generation corresponding to 100% of the Installed capacity of the generating station or unit (s) thereof. The generating station shall not resort to Valve Wide Open (VWO) operation of units whether running on full load or part load, and shall ensure that there is margin available for providing Governor act ion as primary response. In case of gas/liquid fuel based unit s, suitable adjustment in Installed Capacity should be made by RLDCs/SLDCs for scheduling in due consideration of prevailing ambient conditions of temperature and pressure vis-à-vis site ambient conditions on which installed capacity of the generating station or unit (s) thereof have been specified: Provided that scheduling of hydro stations shall not be reduced during high inflow period in order to avoid spillage: Provided further that the VWO margin shall not be used by RLDC to schedule Ancillary Services. To arrest sharp rise or drop of frequency, quick response from the generators through RGMO is indeed the inevitable requirement for safeguarding the grid. There are still several instances of sharp frequency excursions on daily basis. It has to be contained with the help of automatic primary response from the generating units. SLDC-Gujarat has been consistently pursuing with all the RGMO eligible generators in the State to implement RGMO as per the provisions of IEGC State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 51

60 SLDC has also taken up the matter with all State Generators having lignite based thermal generating units of 200 MW and above, Open Cycle Gas Turbine / Combined Cycle generating stations having gas turbines of capacity more than 50 MW each and all hydro unit s of 25 MW and above to take necessary actions regarding provision and operation of RGMO in their units. State Load Despatch Centre, Gujarat Energy Transmission Corporation Limited 52

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62 Together, we can do great things. STATE LOAD DESPATCH CENTRE GUJARAT ENERGY TRANSMISSION CORPORATION LIMITED 132 KV Gotri Sub Station Compound, Vadodara , Gujarat, INDIA Phone: , II Fax: II