防止误重合闸的电能表外置断路器研制

Development of an External Circuit Breaker of the Power Meter Which Can Prevent Abnormal Reclosing

为了配合智能电表实现智能费控功能,介绍了电能表外置断路器的工作原理,提出了具有防止误重合闸的电能表外置断路器设计。结合微处理器软件控制策略和掉电检测电路,有效识别是输入交流电压跌落引起控制信号变化还是预付费电能表输出控制信号变化,可靠防止电能表外置断路器误重合闸,避免用户被触电的危险。掉电检测系统具有超低功耗特性,满足了相线静态电流小于0.2mA的低功耗要求。

In order to realize intelligent charge control function of the smart power meter,this paper introduced the working principle of an external circuit breaker of the power meter,and proposed the design of an external circuit breaker of the power meter which could prevent abnormal reclosing.With the help of a microprocessor software control strategy and a power failure detection circuit,it could be determined whether input AC voltage drop caused variation of the control signal,or the output control signal of the prepayment power meter changed,so that abnormal reclosing of the external circuit breaker could be prevented and electric shock of the user could be avoided.The power failure detection system,characterized by ultra-low power consumption,could satisfy the low power requirement that the static current of the phase line should be smaller than 0.2 mA.