10 kV高压电能计量装置电压互感器杂散电容对高压熔断器的影响研究

Research on the effect of a stray capacitance of TV on the high voltage fuse in10 k V high voltage electric energy metering device

高压电能计量装置是10 k V配网的重要组成部分,但在其运行过程中,电压互感器支路上熔断器的异常动作时有发生,危及电网安全。文章针对电压互感器V形接线方式,以互感器的传感原理为基础,从幅值和频率两方面探讨了支路过流的可能,并提出真空断路器动作时,由互感器杂散电容引起的安培以上量级过电流是高压熔断器异常动作的关键诱因;然后,借助Ansoft Maxwell和ATP-EMTP软件,完成了杂散参数的求解和仿真模型的搭建,并以真空断路器的动作为例,计及三相非同期性,研究了不同合闸情况下的互感器支路过流情况;最后,针对非同期性和杂散电容带来的过流问题,提出并仿真验证了基于合闸同期性控制和杂散电容控制的支路过流抑制措施,可降低熔断器的异常动作风险,对高压电能计量装置的可靠性提升具有指导意义。

The HY electric energy measuring device is an important part of 10 kV distribution network,but the fuse malfunctions in a transformer branch often occur during operation,thus endangering the safety of power grid.Based on the wiring mode of TV,this paper focuses on the overcurrent caused by the increasing of amplitude and frequency of signals when 2 TVs are connected with the V method.That the current caused by stray capacitance of TV is greater than 1A is the key inducement for high voltage fuses to malfunction when vacuum circuit breaker action is proposed.Then,Ansoft Maxwell and ATP-EMTP are respectively used to calculate the stray parameters and to build the simulation model.Taking the operation vacuum circuit breaker as example,with three-phase asynchronism being taken into account,the overcurrent under different circumstances is analyzed.Finally,measures based on the control of and stray capacitance are taken to suppress overcurrent,which can reduce risks of a fuse malfunction and is of great significance in improving the reliability of HV electric energy metering device.