低压断路器合闸线圈保护的研究

提出一种解决低压合闸线圈烧毁的方案，结合具体要求设计出一种针对低压合闸线圈保护电路。在合闸线圈回路中增加了一个保护装置，当断路器未能及时跳闸时，采用4060芯片延时启动保护，切断合闸线圈回路，从而保护合闸线圈。低压合闸线圈回路在正常工作时能够监视低压主电路的运行状态，在发生短路故障时，能够切断合闸线圈保护回路，避免合闸线圈长时间工作在大电流环境下而烧毁，避免断路器操作机构卡死或者断路器辅助触点切换不正常，导致合闸线圈回路不能及时断开而烧毁的现象发生。

Research on closing coil protection of low-voltage circuit breaker

A scheme to solve closing coil burnout of low-voltage circuit breaker is proposed. A kind of protection circuit in allusion to closing coil of low-voltage circuit breaker is designed in combination with concrete requirements. A protection unit is added to closing coil circuit so as to cut off closing coil circuit by 4060 chip to protect closing coil when breaker can't trip in time. Closing coil of low-voltage circuit not only monitors running conditions of low-voltage main circuit,but cuts off closing coil ...