PQSynergy TM 2011 Chiangmai The Impact of Voltage Sag for PEA Area 1(North) Customers in North Industrial Estate Suwipha Kittitanapisarn. B.Eng(EE) Assist. Chief of Power Quality Section PEA Area1 (North) Chiang Mai, THAILAND suwipai@yahoo.com Provincial Electricity Authority, Thailand 19 - 21 September 2011, Chiang Mai, Thailand

PEA Area1 (North) In Overview The Service Area of PEA Area1(North) is approx. 69,557 km2 , accounting for 13.64 % of the country. 6 Provinces 80 amphors 592 districts 6,611 villages 4,734,252 populations 1,534,755 customers Provincial Electricity Authority, Thailand 2

41 Substations in Responsibility of PEA Area1 (North) (278 Feeders) PEA Substation 115/22 kV MEA PEA Substation 22 kV CSA PEA Switching Substation115 kV MCA CKN Transmission Line 115 kV PEA S THG MCN S S EGAT Substation FAA TNG CR CRA Customer115 kV S CUN CDO MLA PAU WPA MHA S MTG MRM PYA PEA Substation 22kV MTA PAN DKA CHM CMB Total 14 Substations CMD CMF CMA SKP Cement Thai Lampang Public Co.,Ltd. CME LPC CMC LNB S LP-2 PEA Substation 115/22 kV LPB HCA LNA S LP-1 CEA Total 27 Substations NIU NIA LPA CTG S PAS PEA Switching Substation 115kV LNC BGA HOA Total 2 Substations LIA TEA

The Comparison of Peak Load Year 2011 and 2010 MW 1,039.12 991.33 995.73 Higher than = 4.86% Lower than = 4.85% Lower than = 3.92% Lower than = 4.38% Higher than = 7.83% Higher than 4.55% Higher than= 12.5% Jan Feb Mar Apr May June Jul Aug Sep Oct Nov Dec Year 2010 Year 2011

Lamphun Province In Brief 8 Amphors 8 Substations Power Transformer Capacity 490MVA Total Load 175.2 MW UF. 40.87 %

Transmission Loop Line Project in Chiangmai Area MRM MRM Now Open Looped Peak Load 300 MW 1,630 A DKA CMD CMD CMF CMF CME CME SKP SKP LNC,NIA,NIU, LNC,NIA,NIU, CMC CMC

Introduction North Industrial Estate NIU Substation North Industrial Estate Lot2 North Industrial Estate Lot1 NIA Substation 3 Substations Power Transformer Capacity 240 MVA Total Load 101.7 MW UF. 48.42 % 8 Amphors 8 Substations Power Transformer Capacity 490MVA Total Load 175.2 MW UF. 40.87 % LNC Substation Sahapat Industrial Estate 115kV CMC- LNC

Report of Average SAIFI Indices (Accumulated from Jan-June 2011) Compare with Target (Level3) in Year 2011 Lower than 21.47% Times per customer per year Industrial Estate City Municiple District Municiple SubDistrictt Municiple Residental Area Total SAIFI Year 2011 Target Year 2011

Report of Average SAIDI Indices (Accumulated from Jan-June 2011) Compare with Target (Level3) in Year 2011 Lower than27.35% Minutes per customer per year Industrial Estate City Municiple District Municiple Subdistrict Municiple Residental Area Total SAIDI Year 2011 Target Year 2011

Voltage Sag (IEEE Std.1159-1995) To Industrial Customers, a Voltage Sag and Momentary Interruption are equivalent if both shut their process down

Fault in Transmission and Distribution Line While the Fault is in the Transmission System, the Entire Power System, including the Distribution System will experience Voltage Sag and Fault are cleared 3-6 cycles for Fault Detection and Breaker Operation 22 kV 115kV 22 kV/400 V 2500 KVA DYn11 Severity of Voltage Sag depend on - Fault Location - Fault Sizing - Fault Type and Clearing Time of Protection Equipment Provincial Electricity Authority, Thailand 11

Study of Voltage Sag Analysis in North Industrial Estate Process of Voltage Sag Prediction 1.To Correctly Prepare Single Line Diagram of North Industrial Estate Area from PEA-GIS Phase2 Web Database 2.Performing Short-Circuit Simulations with Sliding Faults which include Line to Line, Line to Ground and Three Phase Faults in Digsilent 14.0 Simulation Program. 3.Calcutaion Magnitude of Voltage Sag at Interesting Load 4.Predict Voltage Sag Duration Time by Characteristic of Clearing Fault of Protection Equipment 5.Compare Characteristic of Voltage Sag for Determine the Need for Power Conditioning Equipment at Sensitive Loads in Customer Area Provincial Electricity Authority, Thailand 12

Theory of Voltage Sag Analysis V sag = Z 2 + Z f Impedance Divider Z 1 + Z 2 + Z f Provincial Electricity Authority, Thailand 13

Transmission Line from CMC to LNC Provincial Electricity Authority, Thailand 14 14

Process to Voltage Sag Analysis 1.Prepare Single Line Diagram from PEA-GIS Phase 2 Web Database Provincial Electricity Authority, Thailand 15

GIS Phase 2 Provincial Electricity Authority, Thailand 16

Export Single Line Diagram from GIS Phase 2 as *dz files Provincial Electricity Authority, Thailand 17 17

3. Merge. dz Files in Digsilent Power Factory Version 14 3.Merge *.dz Files in Digsilent Power Factory Version 14.0 and start to run Sliding Fault Calculation Provincial Electricity Authority, Thailand 18 18

Voltage Sag from Transmission Fault *OPTREX is a Customer in North Industrial Estate Lot1 Provincial Electricity Authority, Thailand 19

(Continued) Voltage Sag from Transmission Fault Provincial Electricity Authority, Thailand 20

Description Voltage Sag from Distribution Fault Provincial Electricity Authority, Thailand 21 21

For Parallel Feeder (NIU01,03,05 = 0.49 pu.) 4. The Result For Fault at NIU02 ,5 km. From NIU Substation 3P-Fault=3.63 kA, distance =5km. V=0 pu. 0.14 pu. For Parallel Feeder (NIU01,03,05 = 0.49 pu.) S Drissen 0.43 pu. 0.46 pu. Provincial Electricity Authority, Thailand 22 22

Voltage Sag Summary from Distribution Fault Provincial Electricity Authority, Thailand 23 23

(Continued)Voltage Sag Summary from Distribution Fault Provincial Electricity Authority, Thailand 24

Voltage Sag Occurrence Calculation Summary from Transmission and Distribution Fault Provincial Electricity Authority, Thailand 25

Voltage Sag Occurrence Calculation Summary from Transmission and Distribution Fault Provincial Electricity Authority, Thailand 26 26

How Often for Customers to Meet Voltage Sag? How Often for Sag 40% at Drissen Co.,Ltd.(NIU02) In 8 Months? Drissen Co.,Ltd. Meet Sag 40% = Uniform Fault Rate x Distance from NIU-Drissen = 0.17 (Faults/km-year) x 1 km. = 0.17 sags / 8 Months Provincial Electricity Authority, Thailand 27 27

Installation Dranetz-BMI PX5-400 POWER Analyzer 1.At Chiangmai 3 Substation(CMC) 2.At OPTREX Co.,Ltd.(NIA10) 3.At Drissen Co.,Ltd.(NIU 02) Provincial Electricity Authority, Thailand 28

Power Quality Measurement at OPTREX Co.,Ltd. 3 times for Transient 25 Jul – 26 Jul 2011 Provincial Electricity Authority, Thailand 29

Power Quality Measurement at Drissen Co.,Ltd. Abnormal Harmonic 5th order at Main Capacitor 12 Sep – 15 Sep 2011 Provincial Electricity Authority, Thailand 30

Power Quality Measurement at Central Pattana Chiangmai Two events of Voltage Sag at MDB11 from 10 -16 Jun 2011 Instantaneous(0.01-0.6S) Sag 46% Provincial Electricity Authority, Thailand 31

Conclusion The Impact of Voltage Sag for PEA Area 1(North) Customers in North Industrial Estate 1. The Result of 1P-Fault in 115 kV Transmission Line (From CMC to LNC Substation) Effects Voltage Sag not less than 0.8 pu. 2. The Result of 1P-Fault in 22 kV Distribution Line (NIU,NIA,LNCSubstation) Effects Voltage Sag not less than 0.6 pu. 3. Uniform Fault Rate of LNC Substation (From TR.1) has the Most Value and Implies that at the Same Distance from Substation if Comparing with Other Substation in Industrial Park ,LNC Substation (From TR.1) must have the Most Effect from Voltage Sag Provincial Electricity Authority, Thailand 32

Suwipha Kittitanapisarn. PEA Area1 (North) Chiang Mai, THAILAND suwipai@yahoo.com Provincial Electricity Authority, Thailand