High-voltage Isolation Current Sensor by using Signal Modulation Method

Abstract

The signal processing circuit of shunt type current sensor is directly coupled with the high voltage electric circuit so that the common-mode interference signal conditioning becomes a problem. This paper proposes a high-voltage isolation current sensor employs modulation and demodulation which is based on shunt output signal. There is an electrical isolation is set between the high voltage and the low voltage to solve the poor anti-interference ability of shunt type current sensor. The test results show that the current measurement accuracy of the proposed sensor is 0.4%.