WP4.3: Characterization of Electrical Scenarios

Transcription

1 WP4.3: Characterization of Electrical Scenarios Authors: CEA, UPC, TTA Date: 27/Sept/2013 Distribution of document: External Version: 3 Status of the document: Revision Approved for: Joan Tarragó, WP4.3 coordinator Nicola Buggatti. MedSolar coordinator 0

2 The project Machrek Energy Development- Solar (MED-Solar) is implemented under the ENPI CBC Mediterranean Sea Basin Programme ( Its total budget is [3,02 million Euro] and it is financed, [for an amount of 2,66 million Euro], by the European Union through the European Neighbourhood and Partnership Instrument. The ENPI CBC Med Programme aims at reinforcing cooperation between the European Union and partner countries regions placed along the shores of the Mediterranean Sea The ENPI CBC Mediterranean Sea Basin Programme is a multilateral Cross-Border Cooperation initiative funded by the European Neighbourhood and Partnership Instrument (ENPI). The Programme objective is to promote the sustainable and harmonious cooperation process at the Mediterranean Basin level by dealing with the common challenges and enhancing its endogenous potential. It finances cooperation projects as a contribution to the economic, social, environmental and cultural development of the Mediterranean region. The following 14 countries participate in the Programme: Cyprus, Egypt, France, Greece, Israel, Italy, Jordan, Lebanon, Malta, Palestinian Authority, Portugal, Spain, Syria, Tunisia. The Joint Managing Authority (JMA) is the Autonomous Region of Sardinia (Italy). Official Programme languages are Arabic, English and French. The European Union is made up of 27 Member States who have decided to gradually link together their know-how, resources and destinies. Together, during a period of enlargement of 50 years, they have built a zone of stability, democracy and sustainable development whilst maintaining cultural diversity, tolerance and individual freedoms. The European Union is committed to sharing its achievements and its values with countries and peoples beyond its borders. DISCLAIMER This publication has been produced with the financial assistance of the European Union under the ENPI CBC Mediterranean Sea Basin Programme. The contents of this document are the sole responsibility of NERC, ERC, UNDP, Solartys, CEA, UPC and TTA, and can under no circumstances be regarded as reflecting the position of the European Union or of the Programme s management structures. 1

3 Content 1. Introduction Object Task timing Standards... 5 VDE-AR-N 4105: standard... 5 EN standard... 7 IEC standard Characterization methodology Results obtained from questionnaires Results obtained from data measurements Frequency analysis Voltage analysis Harmonic analysis in Voltage Harmonic analysis in Current PF analysis Events analysis Annex 1: Questionnaires and characterization methodology

4 Table list Table 1: WP4.3 work plan... 5 Table 2 : Main characteristics in the grids Table 3: Summary of measuring sites in all target countries Table 4: Events analysis Figure list Figure 1: Microgrid structure used in Jordan and Lebanon Figure 2: Palestinian micro-grid type Figure 3: Palestinian micro-grid type Figure 4: Freq. variation in Tahrir - Lebanon Figure 5: Voltage in Anabta - Palestine Figure 6: Voltage ph-ph in Tahrir - Lebanon Figure 7: THD-I in Central Bank Jordan Figure 8: THD-I in An Najah University - Palestine Figure 9: PF results Al Arz Palestine Figure 10: PF results Al Safa - Palestine

5 1. Introduction The MED-Solar project (acronym of Machrek Energy Development) is part of the new European Neighbourhood Policy (ENP) that seeks to reinforce relations with neighbouring countries to the east and south in order to promote prosperity, stability and security at its borders. The main objective of this project is the promotion and implementation of innovative technologies and know-how transfer in the field of solar energy, including that stemming from private sector, and that may be implemented in particular or public facilities through public procurement processes. The energy situation in the target countries (Jordan, Palestine and Lebanon) is similar and critical in terms of energy supply. The quality of the grid is poor and the interruptions are frequent. The installed power capacity is generally undersized and the trend of the energy consumption and the energy generation confirm that this situation will be much worst in the coming years. In front of the incapacity of the states of giving solutions to assure a continuity of energy supply, new technologies must be introduced. The weakness of these grids allows neither the security of supply in critical facilities nor the proper development of the small and medium size industries. Instead of using exclusively generator, the project addresses a solution to reduce the use of this polluting and expensive mean by installing a solar PV system with a transient storage associated to the generators. When the grid is available, the surplus electricity coming from PV might be either injected to grid or used for specific loads. In case of grid interruption, the back-up is assured by the PV system coupled with generator in case the PV generation is not enough (low irradiation, excess of load, etc). A transient storage system will guarantee the continuity of the supply for very shortterm variations of generation (clouds) or the time that the generator needs to start-up. 2. Object Belonging to the Work Package 4, the characterization of the electrical grid in the target countries is an important task that will help to define the technical challenges that the innovative technologies will have to solve. The characterization of the electrical grid is based on the monitoring and recording of selected electrical magnitudes. This monitoring has been done in several sites that have been considered as representative. Indeed, this deliverable should give inputs for Work Package 5, definition of technical requirements. 4

6 3. Task timing WORKPLAN 2013 Id Description National grid analysis & characterization Selection of sites for data acquisition Characterization methodology Data Acquisition Data Analysis & characterisation Definition of needs Table 1: WP4.3 work plan 4. Standards VDE-AR-N 4105: standard PV inverters nowadays are designed for PV connection onto networks with specific and strict voltage characteristics. Therefore, the inverters system/network and system protection (NS protection) (as called in VDE-AR-N 4105: standard) is rigorously configured to disconnect the inverter in case the grid voltage and frequency are out of those strict limits. This way, today the most complete standard/guide for the connection of distributed power generation units to the low voltage network is the German VDE-AR-N 4105: Power generation systems connected to the low-voltage distribution network Technical minimum requirements for the connection to and parallel operation with low-voltage distribution networks which is followed by most PV inverter constructors. The VDE-AR-N 4105: imposes the following functions of decoupling protection: Voltage drop protection: The inverter needs to disconnect from the grid in less than 200ms when the voltage is lower than 0,8 the nominal voltage of the grid. The protection device of the inverter should use the half-wave RMS voltage value for this decoupling function. Rise-in-voltage protection: The inverter needs to disconnect from the grid in less than 200ms when the 10 minute running mean value (linked with EN standard, see section 1.1) is higher than 1,1 the nominal voltage of the grid. The 10 minute mean value of the voltage needs to be calculated at least every 3 seconds. 5

7 Rise-in-voltage protection: The inverter needs to disconnect from the grid in less than 200ms when the voltage is higher than 1,15 the nominal voltage of the grid. The protection device of the inverter should use the half-wave RMS voltage value for this decoupling function. Frequency decrease protection: The inverter needs to disconnect from the grid in less than 200ms when the grid frequency is lower than 47,5Hz. The frequency measurement method is not specified. Frequency increase protection: The inverter needs to disconnect from the grid in less than 200ms when the grid frequency is higher than 51,5Hz. The frequency measurement method is not specified. Islanding protection: The detection of the isolated network and the disconnection from the grid of the inverter needs to be done in less than 5 seconds. For all those protection functions, the tolerance between the setting values and the actual tripping values must not be higher than +/-1% for voltage and +/-0,1% for frequency. Battery inverters (Sunny Island, Xtender, ) used for off-grid applications, which can also function connected to the public grid or to a genset, are usually configurable in terms of grid voltage quality and limitations. Indeed, depending on the genset s output voltage quality and stability for example, the battery inverter s disconnection conditions can be differently configured. Nevertheless, this limits need to be well checked with constructors. In order to conclude on the possibility of using standard inverters ( VDE-AR-N 4105: certified) in Medsolar s project target countries as well as for the gathering of other kinds of information, the following grid electrical parameters have been defined as important to be monitored on different sites of the target countries for at least 1 month with a time interval of 1 minute: RMS grid voltage RMS load current Grid frequency Power factor Active and reactive power Voltage and current THD Over voltages (swells) Holes in voltage (Dips) Cuts in voltage (interruptions) 6

8 EN standard The EN standards defines the values and limits of each of the principle characteristics of the voltage supplied by a LV (low voltage), MV (medium voltage) and HV (high voltage) public network at the users connection point. This standard has be closely taken into account for VDE-AR-N 4105: standard development. This way, in order to be sure that a typical PV inverter would properly function connected to a LV grid, the grid would need to be in accordance with EN standard (for interconnected grids). The limits defined by the EN are the following: Frequency for interconnected grids: 50 Hz +/- 1% (49,5 Hz 50,5 Hz) during 95% of the time of 1 year. 50 Hz + 4%/- 6% (47 Hz 52 Hz) during 100% of time. Frequency for island grids: 50 Hz +/- 2% (49 Hz 51 Hz) during 95% of the time of 1 week. 50 Hz +/- 15% (42,5 Hz 57,5 Hz) during 100% of time. Voltage: U N (grid nominal voltage) +/- 10% (Excluding interruptions) for 95% of the RMS values averaged over 10 minutes (for periods of 1week). (U N (grid nominal voltage) +10%/-15% for users far away from the transformer). Voltage unbalance: The negative sequence of the fundamental component is between 0% and 2% of the positive sequence for 95% of the values averaged over 10 minutes (for periods of 1 week). Harmonics: The total harmonic distortion in voltage, including up to 40 th harmonics, needs to be lower than 8%. However, the EN standard does not describe the measurement methods for each of the parameters mentioned here above. The standard IEC is mentioned for this purpose. IEC standard The measurement of grid quality parameters can be realized following IEC standard which describes Power quality measurement methods. This standard is mentioned and has been used in VDE-AR-N 4105: standard. The IEC standard defines a basic measurement time interval of 10 cycles for a 50 Hz grid (12 cycles for a 60 Hz grid) for RMS (Root Mean Square) voltage, harmonics (and interharmonics) and unbalance. This basic time interval of 10 cycles is 7

9 then used for 3 seconds (very short intervals) average calculations and for 10 minutes (short intervals) and 2 hours (long intervals) average calculations. It also defines the time interval for average frequency measurement, every 10 seconds. The measurement of the following parameters is then described in the IEC standard: Voltage: The measurement of the RMS value of the voltage shall be done as mentioned above, over a 10 cycle (for 50 Hz grids) time interval. Frequency: As mentioned above, the average value of the frequency shall be measured over 10 seconds periods. Voltage dips (undervoltage), swells (overvoltage) and interruptions: The measurement of a voltage dip, swell and interruption is the U RMS (1/2). The U RMS (1/2) is the RMS value of the voltage (measured over a 10 cycle interval) refreshed every half cycle. The dip and swell phenomenon are characterized by two parameters: the minimum or maximum voltage attained and the duration of the phenomenon. The duration of the phenomenon is calculated from the moment in which the voltage falls or raises the dip or swell threshold until voltage is equal or higher/lower the dip / swell voltage plus/minus an hysteresis voltage. The voltage interruptions are characterized by their duration. Voltage unbalance: The voltage unbalance is estimated by the method of symmetrical components (developed by Charles Fortescue in 1918). The symmetrical components are evaluated trough the fundamental components of the voltage RMS values (measured over 10 cycle time intervals). Harmonics: The measurement of the voltage harmonics is done according to IEC standard (General guide on harmonics and interharmonics measurements and instrumentation, for power supply systems and equipment connected thereto). Flicker: Flicker is measured according to IEC standard. The shortterm flicker (Pst) is measured over 10 minutes intervals and long-term flicker (Plt) is measured over 2 hours intervals. The P st characterizes the probability for the voltage fluctuations to result in perceptible light flicker for the human eye. The IEC standard fulfillment verification requires the use of Class A measuring instruments. 8

10 5. Characterization methodology In order to provide several guidelines for evaluating the main characteristics of the electricity grid and to understand the needs and technical constrains, a characterization methodology was proposed. The document was divided into two different parts. The first one is a questionnaire devoted to collect basic data on the electrical scenarios or sites where the grid will be characterized. The second part is intended to establish the measurement methodology for this characterization. The document also suggested the location of several measurement points in the grids under test to record a set of parameters which will help to both the functional characterization and the modeling of the grids, as well as to check their power quality. Questionnaire and proposed methodology can be found in Annex 1 6. Results obtained from questionnaires The analysis of the questionnaires sent by the local partners, according to the objectives for a first approach to the technical needs, allowed: The identification of the structure (topology and elements) of the micro grids under study as well as the beneficiary sectors (health, education, industry, etc.). The knowledge of several technical parameters, such as the power loads ranges, the existence of priority loads, or the link to the general distribution network. A preliminary analysis of possible power flows in the micro-grids under study according to the specifications of the MEDSOLAR project. 9

11 Today s micro-grids in Jordan and Lebanon. From the information gathered, the microgrids currently in use in these target countries correspond to the scheme shown in Figure 1: Microgrid structure used in Jordan and Lebanon 400 kva*3 ph (Lebanon) Figure 1: Microgrid structure used in Jordan and Lebanon Today s micro-grids in Palestine 10

12 From the information gathered, this country use two different micro-grids, according to the following figures. Transmission line: 33 kv, 35 km Distribution line: 400 V, over 2 km Figure 2: Palestinian micro-grid type 1 11

13 Transmission line: 33 kv, 35 km Distribution line: 400 V, over 2 km Figure 3: Palestinian micro-grid type 2 Summary of the main characteristics of the grids in the target countries The harvested data from the questionnaires are summarized in the following table 12

14 Jordan Lebanon Palestine Basic grid data Organization NDRC UNDP ERC Main Use Feed 6 buildings Commercial University Any question about schematic interpretation? Basic electrical characteristics Net Metering allowed? Yes Yes Not for now (only large projects) Reactive energy penalties? (PF limit?) Yes, PF limit= 0.88 for medium industries Yes, PF limit= 0.9 Yes, PF limit= 0.92 Earth System TT TN-C, IT (?) TN-S Unexpected grid service interruption less than 0.1 % of time 30% - 40% 1 hour per month Stimated loses from generation to loads No data No data. Estimated in 5% 18% to 24% Interconnection to the mains Yes Yes Yes Transformer nominal power 800 kva 400 x 3ph (?) 250 kva and 400 kva Transformer nominal electrical chars 3ph, D-Y 230 V (L-N), 50 Hz 3ph,Y-D 380/220 V 4 w, 50 Hz 3ph,D-Y 33 k /400V (L-N), 50 Hz 3ph, 4w, 380/220 V, 50 Hz, Dyn11 Genset characteristics Genset use Backup Backup Backup (4 grids) and No genset (2 grids) Nominal power of the genset group 375 kva 300 kva, 135 kva, 35 kva 200 kw, 250 kva (if genset) 500 kva Genset main electrical characteristics 3ph 3ph, 380 V L-L / 220 V L-N, 50 Hz 3ph, 400 V, 50 Hz (if genset) 3ph, 380/220 V, 50 Hz Fuel average cost per day /L 1.5 /L The most used genset in your country is Unknow Lister Perkins Cat diesel, 200 kw / 250 kva Transmission line Has the grid a trasmission line? Yes Yes Yes Transmission line electrical characteristics 3ph, 11 kv, 50 Hz 3ph, 115 kv, solidly grounded 3ph, 33 kv, 50 Hz Transmission line lenght to 2.5 km Loads features Are there priority loads? Not specified No Yes First group of priority loads Drives Lighting Second group of priority loads Lighting Drives or sockets Estimated peak-power for the priority loads 250 A From 10 kw to 102 kw Total contracted power 150 A x 3ph and 800 A x 3ph From 35 kw to 330 kw Non-priority loads description Sockets and outlets Drives Table 2 : Main characteristics in the grids 13

15 7. Results obtained from data measurements Summary of the acquired data in the target countries Site Start Period [dd/mm/yyyy] Jordan Time resolution [min] Total duration [day] Campus of Royal Scientific Society 25/04/ Central Bank 31/07/ Building in Aqaba city 27/11/ Al Hoson College 13/05/ Lebanon Tahrir compound 10/06/ Wakef 13/06/ ,16 USEK university 20/12/ Emkan 27/05/ RMF 03/09/ Palestine Al Arz factory 26/02/ Al safa factory 25/02/ Al watani hospital 21/02/ An najah university* 10/03/2013* 1 / 5 / 10* 36* An najah hospital* 05/12/2013* 5 / 10* 46 Anabta municipality 04/02/ Talae amal school 25/02/ Table 3: Summary of measuring sites in all target countries * For An Najah university, data are discrete and are separate in several time period All measurements have been analyzed and displayed in different graphs through a spreadsheet application. The outputs of this tool are available for all project partners. The outputs of the analysis tool are classified as: - Frequency Analysis - Voltage Analysis - Harmonics Analysis - PF Analysis - Event Analysis 14

16 Frequency analysis For all the sites, measured frequency is within the VDE-AR-N 4105 and the EN standard. However in Lebanon it seems that the average frequency is higher than the other sites in Palestine and Jordan. This could be given because all sites have genset as a backup when the grid is down, which is quite often. Figure 4: Freq. variation in Tahrir - Lebanon 15

17 Voltage analysis For almost all the sites, voltage is within the VDE-AR-N 4105 and the EN standar. To be noted that in Palestine, in Anabta Municipality, voltage is not within the VDE-AR- N 4105 and the EN standard. Figure 5: Voltage in Anabta - Palestine To be noted that for Lebanon, voltage is phase-to-phase and not phase-to-neutral. Although it is not possible to compare with the international standards, it seems that in Lebanon there is a bigger data scattering. 16

18 Figure 6: Voltage ph-ph in Tahrir - Lebanon Harmonic analysis in Voltage For all the sites, THD in voltage is within the EN standard (less than 8% THD-V). To be noted that, except in An Najah University, for the rest of the sites in Palestine there are no measurements of THD-V. 17

19 Harmonic analysis in Current Although THD-I is not under the regulations of the used standards in this study, it has been measured in each site to see the maximum levels, and evaluate the effect that it might have with the coupling of solar inverters. Maximum recommended THD-I use to be at 15% or 20%. The sites with a higher THD-I are in Central Bank (Jordan), and An Najah University (Palestine). Graphic statistic study can be found below. Figure 7: THD-I in Central Bank Jordan Figure 8: THD-I in An Najah University - Palestine 18

20 PF analysis To be noted that for Lebanon - Tahrir, power factor data is given for each phase. For the following sites, power factor in average is below or around 0.8: Lebanon, Tahrir site (could be because of the genset) Palestine, Al Arz factory site Palestine, Al Safa factory site Figure 9: PF results Al Arz Palestine Figure 10: PF results Al Safa - Palestine 19

21 According to the information gathered in the questionnaires, the limits of the PF in each target country are: - Jordan: PF limit = Lebanon: PF limit = Palestine: PF limit = 0.92 Events analysis Voltage event Palestine Lebanon Jordan Over Voltage No Yes No Worst case 140 % of Vn (350 ms) No Under Voltage Yes Yes Yes Worst case Vmin: 217 V 10 % of Vn ( ms) 30% of Vn (960 ms) Interruption No Yes No Worst case 0 % of Vn (6h) Table 4: Events analysis *no more details can be given due to the measuring device To be noted that for Lebanon, events on voltage occurs when the grid goes down and the genset is switched ON. To be noted that for Palestine, some events have been informed in the questionnaires. 20

22 8. Annex 1: Questionnaires and characterization methodology Questionnaire for target countries 21

23 Q1.- About the basic architecture The typical structure considered in existing facilities is as shown in Fig.1. The figure also shows potential measuring points (MP) where the electrical parameters could be recorded. Grid Figure 1.- Basic grid architecture in target countries. In Fig.1: a) The electrical power can be supplied to the loads either by the AC mains or by one or more gensets (generating set). A header switch connects the gensets to the loads in case of main grid failure. A transformer (voltage adapter) can be present to adapt voltage levels for the distribution area. b) There may be a transmission line in the case that the distribution area is far away from the generation zone. In this case, a voltage and/or frequency adapter to the distribution area (wherein the passive loads) may be required. It is assumed that power meters (electrical energy meters to measure the loads consumption) are available in the distribution area. It is assumed that the power flow is unidirectional, i.e flowing from the generation to zone the loads area, as shown in Fig.1 22

24 Q1.1.- First set of questions (To be answered by the target country partners. Please, use red color in your answers in this document and remember Fig. 1) Target country (check one): Jordan Lebanon Palestine For the grid under test Geographical location (geographical name of the site): Main use of electrical power (please indicate whether domestic, industrial, healthcare, etc.): If you have electric wiring diagrams of the installation, please send them to the WP leader. Otherwise, please try to draw a single wiring diagram below by indicating where the utility meter is installed. Are there any national/international power regulations (grid standards) in this grid? (check one): YES NO If any, are these regulations available? (documents, web pages etc ) please specify: Are there historical records on the grid behavior? If any, are these records available (documents, web pages etc ) please specify: 23

25 Specify the per-day time intervals where the grid service is theoretically available: What s the earting system of the grid? (TT, IT, TN-S, TN-C, TN-C- S): (reference: Can you quantify (in per-day percentage of time) the duration of the unexpected grid service interruptions? (please indicate): Do you know the % of electrical losses between generation (mains or genset) and loads? (check one): YES NO If you know these losses, please specify their amount: Is the grid interconnected to the mains? (check one): YES NO If the grid has main AC grid interconnection: The interconnection is (check one): Direct Through a transformer In the case of the presence of a transformer: Nominal power of the transformer (please specify): Please specify the transformer main electrical characteristics (1- phase, 3-phase, star/triangle configuration (D-Y, D-D, etc.) RMS voltages at primary and secondary sides (RMS) line-to-line, line-to-neutral, frequency): Does the grid include gensets? (check one): YES NO If the grid has genset group: Brief description of Generation set (number and type of auxiliary generation units) : 24

26 The genset is for (check one): Backup Primary source The nominal power of the genset group is (please specify): Please specify the genset main electrical characteristics (1-phase, 3-phase, voltages (RMS) line-to-line, line-to-neutral, frequency): What is the estimated genset reconnection time? (please specify): The reconnection maneuver is (check one): Automatic Manual The starter of the genset is (check one): Automatic Manual Type and Brand of GENSET: Type of Alternator: What is the average cost of the fuel used in one day? (please specify): Do you know which are the most used gensets in your country? (model, type, brand): Has the grid a transmission line (see figure 1)? (check one): YES NO If there is a transmission line, specify its main characteristics (1-phase, 3-phase, voltages (RMS) line-to-line, line-to-neutral, frequency, length approximately: Is there some kind of voltage-frequency adapter between the generation and distribution areas? YES NO If yes, please describe the main characteristics of this V-f adapter, for example 1-phase or 3-phase AC, if there exist DC lines, voltages, isolation, etc.: In the load area, are there priority loads? (check one): YES NO If yes, please list the loads ordered by priority level: 25

27 What is the estimated peak-power for these loads? (please indicate): What s the contracted power? Please describe the non-priority loads fed by the grid and their main features: Have you registered electrical consumption profiles of the loads? NO YES If possible, please send these profiles to the WP leader. Can you give us some details about the cost (in ) per kwh of the electrical power produced in this grid? Is there other information you d like to share about the grid under test? : 26

28 Grid characterization methodology 27

29 M0.- Election of the site/s for the grid methodology One or several (preferably) facilities should be selected by the local partners trying to follow the selection criteria: 1: Critical facilities such as hospitals, schools or small/medium size factories 2: Unstable grid supply 3: Existing backup system (GENSET) It is highly recommended to acquire DATA for at least 2 sites. It is highly recommended to acquire DATA for at least 1 month again in the same sites during summer time in order to compare both results. M1.- Grid Characterization methodology Subtask (selection of measuring points) is led by TTA and involves the partners of the target countries (NERC, UNDP-L and ERC). The objective of this subtask is to obtain a list of possible facilities or locations where the necessary measurements will be taken in order to characterize the electrical grid. Subtask (characterization methodology) is also led by TTA and involves the UPC and CEA partners. One of the objectives of this subtask is to generate a document that describes the basic methodology to be followed for developing the electric parameters measurement in the facilities previously selected. The electrical grid characterization is based on the monitoring and recording of selected electrical magnitudes. This monitoring must be done on a grid point that may be considered as representative. In this regard, this basic methodology guide is subdivided in three different sections: Election of monitoring point Electrical parameters to be monitored Suggested power quality recorder device 28

30 M2.- Election of monitoring point The weakness of the electrical grid in the target countries implies both programmed and unexpected grid interruptions. These blackouts are supplied using gensets (diesel generators) in order to guarantee the power supply continuity. Because consumption of the electrical loads can be supplied by two different energy sources (national electrical grid and genset), we consider relevant monitoring the operation of both sources. Switching between these two power sources can be performed using switches operated manually or automatically, but in both cases these switches share a common point with consumptions or loads. Therefore, MP3 must be the point where measurements should be taken, as is illustrated in Fig. 1. In case there is a transmission length longer than 100 m, measurements will be taken in MP4 We think that the monitoring of several electrical parameters on this point will provide information on power quality supplied by both energy sources and about the general behavior of the national electric grid in the locations of the selected facilities. M3.- Electrical parameters to be monitored TTA's experience in the use of grid-connected inverters in target countries indicates that such equipment is not operating properly at all times. This malfunction is associated with the algorithms used to detect island mode operation. In this regard, grid-connected inverters are automatically disconnected from grid when the value of certain electrical magnitudes is outside of a predefined range. Some of these variables and the utilized ranges are: Grid voltage: Vac Frequency: Hz (47.5 Hz 50.2 Hz) Power factor: > 0.95 THD: 5 % for current and 2 % for voltage According to the above, the basic set of electrical magnitudes to be monitored at the measuring point should be: 29

31 RMS grid voltage RMS load current Grid frequency Power factor Active and reactive power Voltage and current THD Over voltages Holes in voltage Cuts in voltage M4.- Suggested power quality recorder device It is possible to find on the market several portable recorders ideals for carrying out quality studies of low voltage distribution networks. Note: remember to accomplish nationality rules fixed in MedSolar project in the procurement contracts Below is a brief description of some of them. M4.1.- BRAVO 332 Network Analyzer and Monitor (KMB systems, s. r. o.) Network monitor BRAVO 332 is a programmable registration measuring device for measuring three-phase distribution systems. It is designed for measurements in substations, switch cabinet low voltage distribution networks. Connection and Measurement 4 voltage inputs 4 current inputs for connecting current probes 1 input for Pt100 (optional) Power supply: From an external AC power VAC Internal battery (for a limited time to bridge short power) 128 samples per period, voltage inputs are read continuously without any gaps Evaluates the measured values as frequency, power, power factor and harmonic components and THD of voltages and currents to the order of 50 30

32 Registration of Measured Data Built-in real-time clock with battery backup Memory "flash" to record the measured data with a capacity of 256 MB Aggregation interval from 1 second to 24 hours Record voltage events (short-term / voltage dips and interruptions) Transfer and Evaluation of Recorded Data USB communication interface for data transmission, device configuration and firmware upgrade WiFi - optional wireless communication Visualization and setup program ENVIS M4.2.- Electrocorder EC-7VAR (acksen) The Electrocorder range is designed to allow electrical engineers costs effectively monitor single and three phase loads. This product will allow voltage, load and reactive power problems to be highlighted quickly for further investigation. Connection and Measurement 3 voltage inputs 31

33 3 current inputs for connecting current probes 1 power factor channel Power supply: From an external AC power VAC Internal battery (the Electrocorder can continue to record for months) 16 samples per period, voltage inputs are read continuously without any gaps Registration of Measured Data Built-in real-time clock with battery backup 384 kb non-volatile SEEPROM memory Aggregation interval from 1 second to 1 hour (1 sec gives 2 hrs logging, 1 hour gives up to 300 days logging) Transfer and Evaluation of Recorded Data USB communication interface for data transmission and device configuration Visualization and setup program ELECTROSOFT M Power Quality Logger (Fluke) The Fluke 1744 Power Quality Logger is sophisticated, robust, easy-to-use electrical power-recording device for the electrician or power quality specialist. The Logger monitors power quality and locates disturbances in low and medium voltage distribution networks. Connection and Measurement 3 voltage inputs 4 current inputs for connecting current probes Power supply from an external AC power VAC (no internal battery) 200 samples per cycle at 50 Hz Evaluates the measured values as Volts and Amps (average, min, max), Power (kw, kva, kvar), Power Factor, Energy, Flicker, Voltage and Current THD, Harmonics, Interharmonics and Frequency. Registration of Measured Data 32

34 8 MB Flash-EPROM memory Aggregation interval from 1 second to 24 hours (the device storage capacity is up to 5,600 intervals and 13,000 events) Record of voltage events (dips, swells, interruptions) Transfer and Evaluation of Recorded Data RS-232 communication interface for data transmission and device configuration Visualization and setup program PQ Log software M4.5.- QUADRENT Power Quality Recorder/Analyzer (Made-sa) QUADRENT is an easy to use instrument for recording and analyzing in detail the voltages, currents, power flows and disturbances in a single or three-phase low voltage network. It includes slow fluctuations, dips, swells, interruptions, frequency deviations and flicker as well as harmonics and inter-harmonics up to Connection and Measurement 3 voltage inputs 3 current inputs for connecting current probes Power supply: From an external AC power VAC Internal battery (the device can continue recording for 1 hour) Sampling rate 10,240 Hz Evaluates the measured values as Volts and Amps (average, min, max), Power (kw, kva, kvar), Power Factor, Energy, Flicker, Voltage and Current THD, Harmonics and Frequency Registration of Measured Data 1 GB memory Aggregation interval from 1 minute to 7 days (for 10 min integration interval the device can log for over 2 months) Record of voltage events (dips, swells and interruptions) Transfer and Evaluation of Recorded Data USB communication interface for data transmission and device configuration Visualization and setup program WINQUAD M4.6.- ReCon T Electrical Energy Logger (CESINEL) 33

35 ReCon series of high-performance electrical energy loggers set a new standard in functionality, versatility, compactness, and ease of use. Preinstalled with built-in flexible coils, installing the logger is a matter of minutes. Connection and Measurement 3 voltage inputs 4 current inputs for connecting current probes Power supply from an external AC power VAC (no internal battery) Evaluates the measured values as Volts and Amps (average, min, max), Power (kw, kva, kvar), Energy (active and reactive), Power Factor and Frequency. Registration of Measured Data Aggregation interval from 1 second to 1 hour (for 10 min integration interval the device can log for over 6 months) Transfer and Evaluation of Recorded Data USB and Ethernet communication interfaces for data transmission and device configuration Visualization and setup program MEDCALScope software SIMON PQ Network Analyzer and Monitor (KMB systems, s. r. o.) Network monitor SIMON PQ is a programmable registration measuring device for measuring the three-phase distribution systems. It is designed for measurements in substations, switch cabinet low voltage distribution networks or directly by customers. 34

36 Connection and Measurement 4 voltage inputs 4 current inputs for connecting current probes 1 input for Pt100 (optional) Power supply: From an external AC power VAC Internal battery (for a limited time to bridge short power) 128 samples per period, voltage inputs are read continuously without any gaps Evaluates the measured values as frequency, power, power factor and harmonic components and THD of voltages and currents to the order of 50 Registration of Measured Data Built-in real-time clock with battery backup Memory "flash" to record the measured data with a capacity of 256 MB Aggregation interval from 1 second to 24 hours Record voltage events (short-term / voltage dips and interruptions) Transfer and Evaluation of Recorded Data USB communication interface for data transmission, device configuration and firmware upgrade WiFi - optional wireless communication Visualization and setup program ENVIS M4.8.- CIR-e 3 Portable Recorder for Energy Audits (CIRCUTOR) 35

37 The CIR-e³ analyzer is a programmable measurement unit that measures, calculates and records the main electrical parameters of single and three-phase industrial networks in its memory. Connection and Measurement 4 voltage inputs 3 current inputs for connecting current probes Power supply: From an external AC power VAC Internal battery (only for real-time clock) 128 samples per period, voltage inputs are read continuously without any gaps Evaluates the measured values as frequency, power, power factor and harmonic components and THD of voltages and currents to the order of 50 Registration of Measured Data Built-in real-time clock with battery backup 2 GB external SD card (with SD memory of 1Gb and 1 minute of register interval, the period estimated to register is 1 year and 8 months) Aggregation interval from 1 minute to 2 hours Record voltage events (short-term / voltage dips and interruptions) Transfer and Evaluation of Recorded Data RS-232 communication interface for data device configuration and firmware upgrade Visualization and setup program CIR-E WEB 36

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39 M4.9.- UMG 604 Power Anlyser and recorder (JANITZA) UMG 604 is a high performance power analyser for measuring, monitoring and checking electrical parameters in energy distribution units. It can be used for consumption data collection and analysis, for power quality monitoring (harmonics up to 40th, short-term interruptions, transients, initial current ), peak demand management and remote monitoring. Connection and Measurement 3 voltage inputs 3 current inputs for connecting current probes Power supply: From an external AC power VAC Sampling rate 20 Hz per channel (8 channels) Evaluates the measured values as Volts and Amps (average, min, max), Power (kw, kva, kvar), Power Factor, Energy, Voltage and Current THD, Harmonics and Frequency. Registration of Measured Data 128 MB memory Aggregation interval from 1 minute to 7 days (for 10 min integration interval the device can log for over 2 months) Record of Transients (>50μs), Start-Up processes, Faults, Short-Term Interruptions. Transfer and Evaluation of Recorded Data RS 232, RS 485, Ethernet. Visualization and setup program GRIDVIS. PRICE: 2600 approximately. 38

40 BRAVO 332 EC-7VAR ELITEpro SP 1744 QUADRENT ReCon T SIMON PQ CIR-e 3 M Recorders summary The following table summarizes the measurements made by the power recorders described above. The analysis of this data Analysis of these data allows us to classify the presented power recorders into three main groups: A) Recorder of basic magnitudes: Voltage, current and power measurements. B) Recorder of advanced magnitudes: Basic magnitudes plus flicker and harmonics analysis. C) Recorder of events: Advanced magnitudes plus voltage events as dips, swells and interruptions. Parameter Symbol Line-to-neutral voltage RMS (average, min, max) V L-N Line-to-line voltage RMS (average, min, max) V L-L Current RMS (average, min, max) I Active Power P Reactive Power Q Energy measurements (active and reactive) E Power Factor PF Frequency (average, min, max) f Flicker 39

41 Voltage Dips / Swells Voltage interruptions Voltage unbalance Voltage Harmonics, Interharmonics THD U THD V Current Crest Factor CF Current Unbalance Current Harmonics, Interharmonics THD I THD I Temperature T Recorder group C A A C C A C B In our opinion, it is interesting to record the maximum number of grid parameters in order to obtain a good characterization of the grid at the point-of-connection. In this regard, we suggest the utilization of a type C recorder M5.- Basic methodology guideline for grid characterization To summarize, here is a brief guide with the methodology for the electrical grid characterization in the target countries. 1. Choose the type of recorder and current clamps to use 2. Set the interval length to 1 minute 3. Select the set of parameters to be monitored: At least the following: RMS grid voltage RMS load current Grid frequency Power factor Active and reactive power Voltage and current THD Over voltages Holes in voltage Cuts in voltage 4. Install the recorder at the measuring point MP3 in Fig. 1 (Mp4 in case the transmission length is longer than 100m) 5. Set the recording time to at least 1 month Repeat this procedure if you have another facility to evaluate. 40