INTRODUCTION OF ULTRA-HIGH VOLTAGE (UHV) 1000 kV AC TRANSFORMER

1. INTRODUCTION OF ULTRA-HIGH VOLTAGE (UHV) 1000 kV AC TRANSFORMER Presented By Zhijin Chen TBEA Shenyang Transformer Group Co. Ltd. China

2. Structure of 1000kV AC Transformer

4. Parameters of 1000kV/1000 MVA UHV AC Transformer Made by TBEA, China

5. 1) Rated Capacity HV Winding： 1000 MVA MV Winding： 1000 MVA LV Winding： 334 MVA 2) Rated Voltage HV Winding： 1050/√3kV MV Winding： 525/ √3 ±4×1.25%kV LV Winding： 110kV 3) Rated Frequency： 50Hz 4) Three-phase Connection Symbol：YNa0d11 5) Nominal Short-circuit Impedance(based on 1000MVA)： HV－MV：18% HV－LV： 62% MV－LV： 40%

6. 6) Type of Cooling： • Main Transformer - OFAF • Voltage-regulating Transformer -ONAN • 7) Temp. Rise Limit Value： • Winding： 65K • Top Oil： 55K • Hot-spot: 78K • Tank Surface：80K • Total weight of Main Transformer ：535 ton • Total weight of Voltage-regulating Transformer ：143 ton

7. Rated Short-time Power-frequency Withstand Voltage（r.m.s. value，1min） Rated Lighting Impulse Withstand Voltage (peak value) Rated Switching Impulse Withstand Voltage (relative peak value) Rated Short-time Power-frequency Withstand Voltage (r.m.s. value，5min） Rated Switching Impulse Withstand Voltage（relative peak value） Rated Lighting Impulse Withstand Voltage（peak value） Full Wave Chopped Wave Full Wave Chopped Wave MV 630 kV 1175 kV 1550 kV 1675kV HV 1100 kV 1800 kV 2250 kV 2400 kV Neut. 140 kV / 325 kV / LV(Tert.) 275kV / 650 kV 750 kV 9) Internal Insulation Level：

8. Technical Applied on Design and Production of 1000kV/1000 MVA UHV AC Transformer

9. -- Main Insulation -- Longitudinal Insulation -- 1000kV Leads -- Magnetic Leakage & Losses -- Winding Temp. Rise -- Short-circuit Withstand Capability -- Strength of Tank Transportation -- Seismic Strength

10. Key Technical Characteristic Studies ——Longitudinal Insulation

13. Electric field intensity distribution at the end between LV and HV windings Electric field intensity distribution at the middle part between LV and HV windings

14. Electric field intensity distribution of main insulation calculation by utilizing ANSOFT at the middle part between LV and HV windings. Electric field intensity distribution of main insulation calculation by utilizing ANSOFT at the end between LV and HV windings

15. Key Technical Characteristic Studies ——1000 kV Leads

16. —Magnetic Leakage & Losses 5 Limb Core with 3 Parallel Wound Legs Required Stringent Quality Control to Prevent Circulating Current Losses

17. Key Technical Characteristic Studies ——Winding Temp. Rise

18. Key Technical Characteristic Studies ——Short-circuit Withstand Capability Axial forces on a disc of a winding during short circuit TV winding radial and axial leakage flux distribution

19. ——Strength of Tank Transportation Enlarged diagram of tank stress under transportation condition Diagram of tank metamorphose under transportation condition

20. ——Seismic Strength Diagram of transformer bushing displacement response during earthquake….long bushing needed special analysis Diagram of stress distribution under earthquake situation

21. Some Testing Results on The Product of 1000kV/1000 MVA UHV AC Transformer

24. Total losses tested Guarantee Final Test Load loss, kW 1580 1477.7 No load loss, kW 200 199.9

25. The construction of China’s first 1000kV UHV transmission project was completed successfully in 2008, and passed 168-hour full load energized performance test in January 2009.

26. TBEA Shenyang Transformer Group Co., Ltd. Thank You!