Research on overvoltage and minimum air clearance on 1000 kV AC side of converter transformer in ±1100 kV Guquan converter station

The Journal of Engineering

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[1] State Key Laboratory of Power Grid Environmental Protection, Wuhan Branch of China Electric Power Research Institute, Wuhan 430074, Hubei, People's Republic of China;China Electric Power Research Institute, Wuhan 430074, Hubei, People's Republic of China;

关键词: HVDC power convertors;    power system transients;    power transmission lines;    overvoltage protection;    flashover;    poles and towers;    power grids;    HVDC power transmission;    power transformers;    substations;    UHV DC projects;    minimum air clearance;    AC side;    converter transformer;    AC power grid;    electrode flashover characteristics;    general UHV AC projects;    relevant overvoltage calculation;    related AC system;    power frequency overvoltage;    phase-to-phase overvoltage;    phase-to-phase air clearances;    Guquan converter station;    long wave-front;    Wannan convertor station;    voltage 1100.0 kV;    voltage 1000.0 kV;   

DOI  :  10.1049/joe.2018.8904

来源: publisher

【 摘 要 】

In the hierarchically connected ultra-high voltage (UHV) DC projects, the minimum air clearance on the 1000 kV AC side of converter transformer directly affects the layout and area of the valve hall. The minimum air clearance is determined by the overvoltage and the flashover characteristics of different electrodes. Since the UHV DC projects are hierarchically connected to the AC power grid, the overvoltage and the electrode flashover characteristics are different from that of general UHV AC projects, necessitating the relevant overvoltage calculation and test studies. The electromagnetic transients software PSCAD is used for modelling of the ±1100 kV Wannan convertor station and the related AC system. The power frequency overvoltage, switching overvoltage, time-to-crest value, and coefficient α of phase-to-phase overvoltage on the AC side of the 1000 kV converter transformer are calculated. Tests are carried out on air clearances between bundle conductors, tubular buses, and equipment grading rings under switching impulse with 1000 μs long wave-front. The minimum phase-to-earth and phase-to-phase air clearances on the 1000 kV AC side of the converter transformer are given.

【 授权许可】

CC BY