抽水蓄能电站空载变压器分闸过电压的现场实测与仿真研究

Field Measurement and Simulation Study on Switching Overvoltage of No-load Transformer in Pumped Storage Power Station

为了获得抽水蓄能电站中切除空载主变压器导致的分闸过电压水平,首先通过安装GIS内置式传感器,对实际工程中的空载主变压器分闸过电压进行了实测;而后,对实测波形的波形特征进行了基于EMTP软件的仿真复现和敏感性分析。结果显示,空载主变压器分闸过电压幅值较低,分闸波形中的振荡不是断路器的多次重击穿或铁磁谐振,而是电力变压器的退磁现象,随着高压电缆长度的增加,振荡次数也显著增加。

In order to obtain the switching overvoltage level caused by the removal of no-load main transformer in pumped storage power station,this paper first measured the switching overvoltage of no-load main transformer in practical engineering by installing GIS built-in sensor.Furthermore,the waveform characteristics of the measured waveform are simulated and analyzed based on EMTP software.The results show that the overvoltage amplitude of the no-load main variator is low,and the oscillation in the switching waveform is not the repeated breakdown or ferroresonance of the circuit breaker,but the demagnetization of the power transformer.With the increase of the length of the high-voltage cable,the oscillation times also increase significantly.