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Effect of Power System Harmonic on Equipments. Utility Customers Manufacturers Consultants Research Organizations PQ Standard Organizations Engineers Facility Designers. Research Division, PEA. Harmonic Sources. 6k + 1. SMPS. 12k + 1. DC & AC Drive. Electronic. Arc Furnaces.
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Effect of Power System Harmonic on Equipments Utility Customers Manufacturers Consultants Research Organizations PQ StandardOrganizations Engineers Facility Designers Research Division, PEA
Harmonic Sources 6k+1 SMPS 12k+1 DC & AC Drive Electronic Arc Furnaces Spot Welding Transformer
Symmetrical Component Anticlockwise Clockwise Negative Sequence Positive Sequence Zero Sequence
System Connection & Harmonic Source Harmonic Source 50 Hz Order Sym. 1 + 2 - 3 0 4 + 5 - 6 0 7 + Positive Sequence (+) 3n + 1 H Negative Sequence (-) 3n - 1 Zero Sequence (0) 3n
System Connection & Harmonic ลำดับที่1 2 3 4 56 7 8910 11 ความถี่50 100150 200250300350400450500 550 Sym.+ - 0 + - 0+ - 0+- Zero Sequence Zero Sequence
Zero Sequence P Q Q P Reference
Zero Sequence P Q Q P Reference
Zero Sequence P Q Q P Reference
Zero Sequence P Q Q P Reference
Zero Sequence P Q Q P Reference
Power Quality Monitoring Unipower Model 902 Meridian Fluke Model41B Hioki Dranetz Model 658
Harmonic Power Flow 50 Hz + - Source Power Sink Source Sink
Ex. Harmonic Power Flow 50 Hz + - Power Source Sink
Harmonic Power Flow Source
Harmonic Series Resonance (Low Impedance) Impedance (Z) R h 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Harmonic Order
Finding Harmonic Series Resonance Order 1 MVAZ = 6.5 %
Harmonic Parallel Resonance (High Impedance) Impedance (Z) R h 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Harmonic Order
Harmonic Parallel Resonance (High Impedance) MVASC-HV MVA Tr %Z MVASC-LV
Harmonic Parallel Resonance (High Impedance) 100 MVASC-HV 1 MVA Z = 6.5% MVASC-LV
Effect on Miniature Circuit Breaker Thermal Trip (Overload) 5วินาที 1วินาที MCB Magnetic Trip (Short Circuit)
1,000 100 10 Time (seconds) 1 0.10 0.01 100 1,000 10,000 100,000 Rated Current (%) Effect on Fuse Maximum Clearing Time Fuse 0.4 Sec < 0.4 Sec Relay Minimum Melting Time
Components of Capacitor I. Dry-type - no pollution or leakage risk II. Sequential Protection System • Self-Healing Capacitor Elements • Internally Protection Elements • Nonflammable Dry Vermiculite Filter III. Discharge Resistors IV. Terminal Studs V. Thermal equalizer VI. Steel enclosure VII. Light weight easy to install IPE Element IPE Wires Winding core Can Resin filling Sprayed contact layer Non self- healing windings Fuse Capacitor winding Sprayed contact layer
Components of Capacitor • Electrode : a microscopically thin layer of conducting material, aluminum or zinc 0.01 microns • Dielectric : Polypropylene range from 5 to 10 microns Polypropylene Dielectric Aluminum Foil Electrode
Effect on Capacitor Voltage Dielectric Stress = Thickness
Harmonic and Capacitor Selection Sn :ขนาดของหม้อแปลง (kVA) Gh :ขนาดของโหลดที่สร้าง ฮาร์มอนิกส์(kVA)
Harmonic and Capacitor Selection 400V 470/525V 525V Reactor
Effect on Relay Peak Sensing Peak Sensing Under protected Over protected True RMS Sensing Sampling Harmonic
L3 3.L3 L1 3.L1 N L2 3.L2 Effect on Ground Relay
Effect on Meter V I V I
Effect on Conductors Skin Effect x Y
Effect on Conductors Proximity Effect กระแสไหลในทิศทางเดียวกัน กระแสไหลในทิศทางตรงข้ามกัน
Effect on Conductors 300 250 200 150 100 50 0 500 mm2 Increase in AC resistance(%) 240 mm2 185 mm2 70 mm2 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 Harmonic Order
Effect on Conductors Copper Losses (Load Losses)
Effect on Transformer Skin Effect Proximity Effect Copper Losses Eddy Current Losses คือ ค่าความสูญเสียจากกระแสไหลวนในขดลวดของหม้อแปลงไฟฟ้า เมื่อจ่ายโหลดแบบ Linear ที่พิกัดกระแส (50 Hz)
Effect on Transformer Transformer Derating (K Factor) คือ ค่าความสูญเสียจากกระแสไหลวนในขดลวดของหม้อแปลงไฟฟ้า เมื่อจ่ายโหลดแบบLinear ที่พิกัดกระแส (50 Hz)
Effect on Transformer Transformer Derating (K Factor) คือ ค่าความสูญเสียจากกระแสไหลวนในขดลวดของหม้อแปลงไฟฟ้า เมื่อจ่ายโหลดแบบLinear ที่พิกัดกระแส (50 Hz)
Effect on Transformer Transformer Derating (K Factor) Transformer 25 MVA at 22 kV
Effect on Transformer Transformer Derating (K Factor)
Effect on Transformer Transformer Derating (K Factor)
Effect on Transformer Transformer Derating (K Factor) Transformer can operate without damage Transformer can be damaged