Present situation and development trend of control and protection technology for mine-used combined switch

Present situation of control and protection technology for mine-used combined switch was introduced from aspects of short circuit protection, overload protection, leakage lockout and leakage protection, transient overvoltage protection and temperature protection. Problems of control and protection technology for mine-used combined switch such as incomplete relay protection, protection misoperation, complicated control mode and simple self-diagnosis were pointed out. Development trend of control and protection technology for mine-used combined switch were put forward, including improvement of relay protection method and software filtering method, control intensification, intelligent self-diagnosis and remote diagnosis.