具有双重漏电保护智能断路器设计

Design of Intelligent Circuit Breaker with Double Leakage Protection

提出一种利用双独立零序电流互感器检测漏电流信号进行双重漏电保护方法,一路漏电流信号提供给独立漏电保护电路,另一路通过信号处理,提供给ST单片机采样。当出现漏电流值超过动作电流整定值且独立漏电保护模块失效不起作用,断路器无法分闸时,单片机通过控制电机及时分闸操作,起到二次保护作用。本文给出了实现该方法的硬件原理及软件流程图。试验结果表明,该方法研制出的漏电断路器稳定、安全可靠,具有真正的双重漏电保护功能。

This paper proposes a double leakage protection method by using double independent zero sequence current transformer to detect leakage current signal.One leakage current signal is provided to the independent leakage protection circuit,and the other is provided to the ST MCU for sampling through signal processing.When the leakage current value exceeds the action current setting value and the independent leakage protection module fails to work,so the circuit-breaker can not be opened,the MCU can be used by controlling the motor to open in time,it has the function of secondary protection.This paper presents the hardware principle and software flow chart of the method.The test results show that the residual current circuit-breaker developed by this method is stable,safe and reliable,and can really play a dual leakage protection function.