某智能变电站220 kV CVT 分频谐振分析

摘要

电容式电压互感器（CVT）在电力系统得到广泛应用，但当电力系统发生冲击或故障时，由于CVT中含有电容及电感类的储能元件，可能会发生铁磁谐振现象。某智能变电站220 kV新设备在送电过程中CVT 二次电压出现长时间波动，经分析认为 CVT 出现了能长时间自保持的分频谐振。通过对其产生原因的分析，提出了改进措施，并经现场证明有效，这为防范此类 CVT 的分频铁磁谐振提供了新的方法。%Capacitor voltage transformer (CVT) has found wide application in the power system. However, in case of impulse or fault in the power system,Ferro-resonance maybe occurred due to the capacitive or inductive charging elements in the CVT. Long time fluctuation of secondary voltage of CVT is occurred at new 220 kV equipment at certain intelligent substation during the power transmission period. It is thought through analysis that CVT has long time self-sustaining frequency resonance. The improvement measures are proposed by way of analysis of its reason and are proved at site to be effective,which provides new method in preventing frequency resonance of such CVT.