电能表射频电磁场辐射抗扰度试验案例分析

Case analysis of immunity to radiated RF electromagnetic fields of electricity meter

结合电能表在射频电磁场辐射抗扰度试验(RS)中出现频繁自动重启的案例,分析产生该异常现象的原因,给出了消除该干扰的解决方法。在该案例中,射频电磁场在电源电路中引起的电压波动触发了掉电检测信号,引起自动复位重启。通过在电压基准源芯片的参考引脚和地之间并接旁路电容,滤除来自空间射频电磁场在环路中引入的干扰电压,有效解决了该问题。

For the case that the continually reset and restart of electricity meter in immunity to radiated RF electromagnetic field,the causes of the abnormal phenomenon are analyzed,and the solutions to eliminate the interference are given.In this case,the induced voltage fluctuation in the power circuit triggers power failure detection signal event,causing an automatic reset and restart.The interference voltage introduced from RS is filtered out using a by-pass capacitance between the reference pin of the reference voltage chip and the ground,which effectively solves the problem.