10 kV系统电压互感器防止铁磁谐振过电压的二次接线改进

Improvement on secondary connection of the voltage transformer to avoid magnetic resonance in 10 kV power supply system

电压互感器运行中会因单相接地诱发铁磁谐振使电压互感器烧毁,分析了引起铁磁谐振的原因,指出了几种常用的消除谐振的方法以及存在的一些不足。通过实验分析提出了一种改进的互感器回路二次侧接线方法,并有效地消除了互感器回路中的三次谐波,这样不仅很好地保护了互感器,也使系统的控制和保护更稳定可靠。该方法应用在10 kV供电系统中,有效地消除了电压互感器的铁磁谐振,起到了很好的应用效果。

Voltage transformer can be destroyed easily when single phase grounding produces magnetic resonance in operation. The paper analyzes the reason of magnetic resonance and points out the shortages of existing methods to avoid magnetic resonance. It offers a method of improving secondary connection of the voltage transformer to eliminate the tri-sine wave in the circuit with experiments, which can not only protect the voltage transformer, but also make the power supply system stable. The method has been used in lOkV power supply system, and has a good effect in the application to avoid magnetic resonance of the voltage transformer.