POWER CONSUMPTION PATTERN MODELING FOR EFFECTIVE DISTRIBUTION NETWORK PLANNING Chai Choung Jung.. Master of Engineering 2009
Puat Khidmat Maklumat Akademik UNIVERSm MALAYSIA SARAWAK Power Consumption Pattern Modeling for Effective Distribution Network Planning P.KHIDMAT MAKLUMAT AKAD!MIK 1IIIIIIIIIIi'i~ 111111111 1000248144 CHAICHOUNGJUNG This thesis is submitted in fulfillment of the requirements for Master of Engineering (Electronics) Faculty of Engineering UNIVERSITI MALAYSIA SARAWAK 2009
DEDICATION Dedicated to my dad, mom, brother, sister and friends 11
ACKNOWLEDGEMENT First and foremost I would like to express my appreciation to everyone who directly and indirectly giving me assistance through out the study. I would like to thank Madam Kho Lee Chin and Dr. Siti Halipah Ibrahim, my academic supervisors, as well as Ir. Leslie Chai Kim Pau and Mr. Alvin Lim Khiok Leong, my industrial supervisors, for giving me guidance and help along the completion of this study. I would like to thank Universiti Malaysia Sarawak (UNIMAS) and Syarikat SESCO Berhad for financial, equipments and facility support throughout the research activities. My deepest thanks to my family for their love, encouragement and support that they have given me throughout the whole process. I would also like to express my sincere thanks and gratitude to my colleagues and friends, Mr. Leong Weng Ik, Miss Elna Akam, Mr. Kusyairi Kipli, Mr.Raden Chekra Muda, Mr. Lee Eng Sian, Mr. Lee Hock Kiong, Mr. Iu Cho Seng, Mr. Bujang Borhan, Mr. Wee Choon Kiat, Mr. Bujang Edin, Mr. Rosli Mustapha, Mr. Mark Errelson, Mr. Yap She Ann, Mr. Tay Chang Siong, Mr. Lai Sung Lin, Mr. Chai Tze Kiong, Mr. Lee Ted Yong and Mr. Bengsoon Siteh for lending their helping hands when I face with difficulty during my study. Finally, my deepest gratitude goes out to all my dearest friends who have given me the moral support, encouragement, assistance and comfort that I needed during these years here. To them, I wish the best of luck and may the future hold bright for you all. 11l
ABSTRACT The demand for electricity is increasing due to population growth. The power consumption pattern become critical issues to be investigated so that the network can be planned, designed and operated efficiently to meet the increasing yearly demand. In this study, multistage cluster sampling is used to calculate the sample size. Power consumption data for every 15 minutes time interval was recorded by using EDMI Mk.6 Genius polyphase electronic (E3) meter. Once power consumption data is collected, power consumption pattern, load factor, diversity factor, after diversity maximum demand, distribution transfonner size and l1kv cable size can be detennined. Analysis on temperature sensitivity related to the demand and method to improve overall load factor will be carried out. The result shows that power consumption pattern is influenced by consumer behaviour, time and weather. For the consumer behaviour factor, differences in numbers, sizes and types of electrical appliance will greatly influence the demand and maximum demand of the power consumption pattern. For time factor, demand for domestic 'consumer is high during nighttime as compared to daytime. Weather is also a factor which can affect the demand. In this study, analysis on temperature sensitivity related to the demand shows that when the temperature increases, the demand will also increase. IV
The result shows that commercial unit floor has the highest value of after diversity maximum demand followed by detached house, semi-detached house, terrace house and residential unit floor. Based on the value of after diversity maximum demand and the unit of different types of consumers needed, more accurate total electrical load, distribution transformer size and 11 kv cable size can be determined. The power consumption pattern model had been created by using graphical user interface. By entering the unit of different types of consumers needed, this model is able to determine accurately total electrical load, distribution transformer size and the 11 kv cable size needed. v
ABSTRAK Pertumbuhan penduduk telah menyebabkan permintaan untuk bekalan elektrik semakin meningkat. Corak penggunaan kuasa menjadi isu kritikal untuk diselidiki supaya rangkaian bekalan elektrik boleh dirancang, direka dan dikendalikan dengan cekap untuk memenuhi permintaan elektrik tah~man yang semakin meningkat. Dalam projek ini, pensampelan kelompok pelbagai tahap (multistage cluster sampling) digunakan untuk mengira saiz sample. Data penggunaan kuasa dengan sela masa 15 minit dirakamkan dengan menggunakan meter pelbagai fasa elektronik (E3) EDMI Mk.6 Genius. Selepas data pengunaan kuasa diperoleh, corak penggunaan kuasa, faktor beban (load factor), faktor kepelbagaian (diversity factor), permintaan maksimum selepas kepelbagaian (after diversity maximum demand, ADMD), saiz transformer agihan (distribution transformer) dan saiz kabel agihan 11kV (J 1kV distribution cable) boleh ditentukan. Analisis terhadap hubungan antara kepekaan suhu dengan permintaan dan kaedah untuk memperbaiki faktor beban dapat ditentukam. Keputusan daripada kajian menunjukkan bahawa corak penggunaan kuasa dipengaruhi tingkah laku pengguna, mas a dan cuaca. Bagi faktor tingkah laku pengguna, permintaan dan mempengarllhi permintaan maksimum corak penggunaan kuasa dipengarllhi oleh jenis, bilangan dan saiz peralatan yang berbeza. Bagi faktor masa, penggunaan bekalan elektrik oleh pengguna VI
domestik adalah tinggi pada waktu malam jika dibandingkan dengan siang hari. Cuaca adalah satu faktor yang memberi banyak kesan terhadap permintaan. Analisis terhadap hubllngan antara kepekaan suhu dengan permintaan menunjukkan bahawa apabila suhu meningkat, permintaan juga akan bertambah. Keputusan menunjukkan bahawa unit komersial itu mempunyai nilai tertinggi bagi permintaan maksimum selepas kepelbagaian. Ini dukuti dengan rumah sesebuah, rumah berkembar, rumah teres dan kediaman atas kedai. Berdasarkan nilai permintaan maksimum selepas kepelbagaian dan bilangan unit komersial, kediaman atas kedai dan pelbagai jenis rumah yang diperlukan serta nilai muatan elektrik yang lebih tepat, saiz transformer agihan dan saiz kabel agihan 11kVyang diperlukan boleh ditentukan. Model corak penggunaan kuasa dibentuk dengan menggunakan perisian MA TLAB. Maklumat-maklumat seperti bilangan unit komersial, kediaman atas kedai dan pelbagai jenis rumah yang diperlukan untuk mengira secara tepat jumlah muatan elektrik, saiz transformer agihan dan saiz kabel 11k V yang diperlukan. Vll
TABLE OF CONTENTS CONTENT PAGE DEDICATION ACKNOWLEDGE NT ABSTRACT ABSTRAK TABLE OF CONTENTS LIST OF FIGURES LIST OF TABLES LIST OF ABBREVIATIONS LIST OF NOMENCLATURE ii iii iv vi viii xv xix xxi xxii Chapter 1 INTRODUCTION 1 1.1 Background 1.2 Statement of Problems 3 1.3 Objectives of the Study 4 l.4 Study Overview 5 Vlll
Chapter 2 LITERATURE REVIEW 6 2.1 Power Distribution System in Sarawak 6 2.2 Planning Criteria 8 2.3 System Loading Limitations 9 2.3.1 331l1kV Substation Transformer 9 2.3.2 Circuit Breaker 11 2.3.3 Distribution Feeder 11 2.3.4 Distribution Transformer 12 2.4 Cable Distribution -11 KV Cable 13 2.4.1 Introduction to l1kv Cable 13 2.4.2 Factor that Determine llkv Cable Used 14 2.5 Power Consumption Pattern 15 2.6 Factors that Determine Consumer Power Consumption Pattern 16 2.7 Standard Definition for Load Combination 17 2.7.1 Demand 17 2.7.2 Maximum Demand 17 2.8 Load Factor 18 2.9 Electrical Load Characteristics 20 2.10 Diversity Factor 20 2.11 After Diversity Maximum Demand 22 2.11.1 Determining of ADMD (int) Values 23 IX
2.12 General Process of Power Consumption Pattern Study 24 2.12.1 Define Type of Consumer 25 2.12.2 Sampling Method 25 2.12.3 Collection of Power Consumption Data 26 2.12.4 Power Consumption Pattern Derivation 27 2.12.5 Make Use of Power Consumption Data and Power Consumption Pattern 27 Chapter 3 METHODOLOGY 29 3.1 Introduction 29 3.2 Role of Power Consumption Pattern 29 3.3 Electrical Load Survey Process 30 3.4 Study Concept 31 3.4.1 Define Type of Consumer 33 3.4.2 Sampling Method 33 3.4.3 Electrical Usage Pattern 35 3.4.4 Power Consumption Data 39 3.4.5 Power Consumption Pattern Derivation 40 3.4.6 Temperature Sensitivity Analysis 41 3.5 Hardware and Software 43 3.5.1 EDMI Mk.6 Genius Polyphase Meter Electronic (E3) Meter 43 x
3.5.2 Zero-Power IECII07 (FLAG) Optical Probe 44 3.5.3 Main Wiring Cable 45 3.5.4 MATLAB R2006b Software 47 3.5.4.1 Introduction to Matlab R2006b 47 3.5.4.2 Graphical User Interface Development Environment (GUIDE) 48 3.5.4.3 Designing a Graphical User Interface 49 3.5.5 EziView Software 51 3.6 Summary 52 Chapter 4 RESULTS AND DISCUSSIONS 54 4.1 Introduction 54 4.2 Sample Design 54 4.3 Design and Analysis of Questionnaire 55 4.4 Analysis of Power Consumption Pattern 57 4.4.1 Detached House Consumer 58 4.4.1.1 Analysis of Power Consumption Pattern 58 4.4.1.2 Maximum Demand 59 4.4.1.3 Load Factor, Diversity Factor and After Diversity Maximum Demand 60 4.4.1.4 Analysis oftemperature Sensitivity 61 4.4.2 Semi-Detached House Consumer 63 4.4.2.1 Analysis of Power Consumption Pattern 63 xi
4.4.2.2 Maximum Demand 64 4.4.2.3 Load Factor, Diversity Factor and After Diversity Maximum Demand 65 4.4.2.4 Analysis oftemperature Sensitivity 66.4.4.3 Terrace House Consumer 68 4.4.3.1 Analysis of Power Consumption Pattern 68 4.4.3.2 Maximum Demand 69 4.4.3.3 Load Factor, Diversity Factor and After Diversity Maximum Demand 70 4.4.3.4 Analysis of Temperature Sensitivity 71 4.4.4 Residential unit Floor Consumer 73 4.4.4.1 Analysis of Power Consumption Pattern 73 4.4.4.2 Maximum Demand 74 4.4.4.3 Load Factor, Diversity Factor and After Diversity Maximum Demand 75 4.4.4.4 Analysis of Temperature Sensitivity 76 4.4.5 Analysis of Power Consumption Pattern for Domestic Consumers 78 4.4.6 Commercial Unit Floor Consumer 79 4.4.6.1 Analysis of Power Consumption Pattern 79 4.4.6.2 Maximum Demand 80 4.4.6.3 Load Factor, Diversity Factor and After Diversity Maximum Demand 81 xu
4.4.6.4 Analysis oftemperature Sensitivity 82 4.5 Comparison of Power Consumption Pattern for Several Types of Consumers 84 4.6 Comparison of Load Factor for Several Types of Consumers 86 4.7 Comparison Diversity Factor and After Diversity Maximum Demand for Several Types of Consumers 88 4.8 Comparison Demand to Temperature Sensitivity Analysis for Several Types of Consumers 90 4.9 Method to Improve Overall Load Factor 91 4.10 Power Consumption Pattern Model 93 4.11 Summary 95 Chapter 5 CONCLUSIONS AND RECOMMENDATIONS 97 5.1 Conclusions 97 5.2 Recommendations 101 BIBLIOGRAPHY 102 APPENDIX 106 A Sample Size Calculation 106 B Questionnaire 118 Xlll
C Letter from Syarikat SESCO Berhad and Universiti Malaysia Sarawak (UNIMAS) for Meter Installation 127 D EDMI Mk.6 Genius Polyphase ELectronic (E3) Meter Specification 129 E Power Consumption Pattern Model Matlab M-File 136 F Power Consumption Pattern Model 146 G Study Sticker 148 H Photo When Doing Meter Installation 149 XIV
LIST OF FIGURES FIGURE PAGE Figure 1.1: Estimate total electricity consumer in Sarawak from year 1996 to 2005 2 Figure 1.2: Total unit sold (TWh) by Syarikat SESCO Berhad from year Figure 2.1: Figure 2.2: Figure 2.3: Figure 2.4: Figure 2.5: Figure 2.6: Figure 2.7: Figure 2.8: Figure 2.9: Figure 2.10: Figure 2.11: Figure 3.1: Figure 3.2: Figure 3.3: 1996 to 2005 Existing generating plants in Sarawak Basic supply system in Sarawak Nameplate for 30MVA transformer 30MVA transformer IlkV feeder 1OOOkVA transformer Power consumption pattern for detached house consumer Explanation of load factor Explanation ofdiversity factor Variation of ADMD with number ofconsumers General process ofpower consumption pattern Process to design the electrical load pattern model Air conditioning units at detached house consumer Air conditioning units at semi-detached house consumer 2 6 8 10 10 12 13 16 19 21 22 24 32 37 37 xv
Figure 3.4: Air conditioning units at terrace house consumer 38 Figure 3.5: Air conditioning units at commercial unit floor (ground and 1 51 floor) and residential unit consumer (2 nd floor) 38 Figure 3.6: Example of usage pattern of air conditioning units by semi-detached house consumer 39 Figure 3.7: Example ofpower consumption pattern for semi-detached consumer 41 Figure 3.8: Example of graph on demand by temperature for terrace house consumer 42 Figure 3.9: Example of adding trend line to the original line for terrace house consumer 43 Figure 3.10: EDMI Mk.6 Genius polyphase electronic (E3) meter 44 Figure 3.11: Zero-power IECII07 (FLAG) optical probe (F6Z-P-D09F-2R) 45 Figure 3.l2: Main wiring cable, EDMI Mk.6 Genius polyphase electronic (E3) meter and the kilowatt-hour meter 46 Figure 3.13: Interfacing of MA TLAB R2006b 48 Figure 3.14: GUI flowchart of power consumption model 49 Figure 3.15: Layout Editor of the GUIDE 50 Figure 3.16: GUI layout of the power consumption pattern system 51 Figure 3.17: EzView software interface 52 Figure 4.1: Usage pattern of air conditioning units for several types of consumers 57 Figure 4.2: Power consumption pattern by detached house consumer 59 Figure 4.3 : Graph on demand by temperature for detached house consumer 61 XVI
Figure 4.4: Adding trend line to the original line for detached house consumer 62 Figure 4.5: Power consumption pattern by semi-detached house consumer 64 Figure 4.6: Figure 4.7: Graph on demand by temperature for semi-detached house consumer 66 Adding trend line to the original line for semi-detached house consumer 67 Figure 4.8: Power consumption pattern by terrace house consumer 69 Figure 4.9: Graph on demand by temperature for terrace house consumer 71 Figure 4.10: Adding trend line to the original line for terrace house consumer 72 Figure 4.11: Power consumption pattern by residential unit floor consumer 74 Figure 4.12: Figure 4.13: Graph on demand by temperature for residential unit floor consumer 76 Adding trend line to the original line for residential unit floor consumer 77 Figure 4.14: Power consumption patterns for several types ofdomes6c consumers 78 Figure 4.15: Power consumption pattern by commercial unit floor consumer 80 Figure 4.16: Figure 4.17: Graph on demand by temperature for commercial unit floor consumer 82 Adding trend line to the original line for commercial unit floor consumer 83 Figure 4.18: Comparison of power consumption pattern for several types of consumers 85 Figure 4.19: Load factor for several types ofconsumers 87 Figure 4.20: Improving load factor 91 Figure 4.21: Interface of power consumption model 94 XVll
Figure 4.22: By entering the number of unit needed, total electrical load, distribution transformer size and llkv cable size can be determined 94 XVlll
LIST OF TABLES TABLE Table 2.1: Table 3.1: Table 3.2: Table 3.3: Table 3.4: Table 3.5: Table 4.1: Table 4.2: Table 4.3: Table 4.4: Table 4.5: Table 4.6: Current rating for several types of 11 k V cables Survey area Five types of consumers Energy consumption for several types of electrical appliances Power consumption for a consumer at the selected time within 15 minutes interval Specification of the main wiring cable Sample size Percentage of useable questionnaire return rate Maximum demand and time when maximum demand occur for detached house consumer Load factor, diversity factor and after diversity maximum demand for detached house consumer Maximum demand and time when maximum demand occur for semi-detached house consumer Load factor, diversity factor and after diversity maximum demand for semi-detached house consumer PAGE 14 30 31 35 40 47 55 56 60 60 64 65 XIX
Table 4.7: Maximum demand and time when maximum demand occur for terrace house consumer 69 Table 4.8: Load factor, diversity factor and after diversity maximum demand for terrace house consumer 70 Table 4.9: Maximum demand and time when maximum demand occur for residential unit floor consumer 74 Table 4.10: Load factor, diversity factor and after diversity maximum demand for residential unit floor consumer 75 Table 4.11: Maximum demand and time when maximum demand occur for commercial unit floor consumer 80 Table 4.12: Load factor, diversity factor and after diversity maximum demand for commercial unit floor consumer 81 Table 4.13: Summary of maximum demand and time when maximum demand occur for several types of consumers 85 Table 4.14: Summary of load factor for several types of consumers 87 Table 4.15: Summary of the diversity factor and after diversity maximum demand for several types of consumers 89 Table 4.16: Equation relate demand to temperature and.r-squared value for several types of consumers 90 Table 4.17: Load factor for the different combination of two consumer groups 92 Table 5.1: Problems and ways to solve the problem 100 xx
LIST OF ABBREVIATIONS ADMD ABI Al Cu CSBD PVC RMU XLPE 3C After Diversity Maximum Demand Air Break Isolators Aluminium Copper Central & Suburban Business District Polyvinyl Chloride Ring Main Unit Cross-Linked Polyethylene 3 Cores XXI
LIST OF NOMENCLATURE e N p q S T z Proportion of sampling error Size of the population Population proportion (l-p) Sample size Temperature Standard score corresponding to a given confidence level XXll
CHAPTER! INTRODUCTION 1.1 Background Rapid growth of population and depletion of fossil fuel has generated subsequent increase in demand for electrical power. Nowadays, electricity is supplied to different types of consumers such as detached house, semi-detached house, terrace house, commercial unit-floor and residential unit-floor. Different types of consumers use different amounts of electricity. The total number of electricity consumer in Sarawak has increased every year from 260,214 in 1996 to 414,767 in 2005. The growth rate of electricity consumers within 10 years is 59.39%. Total electricity sold is 1.94TWh in 1996 and increased to 3.94TWh in 2005. The growth rate of total electricity demand within 10 years is 103.09%. The number of electricity consumer and the total amount electricity demand increased dramatically as shown in Figure 1.1 and Figure 1.2 respectively. The power consumption pattern, consumer behaviour and electrical load characteristic become a critical issue to be investigated in order to design better efficient system in planning, operation and maintenance to meet the increasing yearly demand (Ngu et al., 2007).