Development and application of non-electric coupling DC sensor

A kind of non-electric coupling DC sensor—magnetic coupling sensor is developed.The magnetic coupling theory is maily applied.The signal can be accurately detected by the sensor when ground fault occurs in DC system.The detecting range of the fault current is ±5mA.The sensor has some merits,for example:small volume,accurate measurement,high sensitivity,anti-interference and no effect on DC operating circuit.The grounded line of DC system can be successfully determinded by the sensor in power station and substation.