A Broadband Current Sensing Device Based on Tunnel Junction Magnetoresistance Sensor for Smart Grid Applications

According to the demand for high-frequency transient current measurement in power systems, a current sensor based on tunnel junction magnetoresistance(TMR) with high bandwidth is proposed. This scheme reduces the stray parameters of the circuit by simplifying the circuit system and designing electromagnetic shielding, so that the bandwidth of the current sensor is increased to 8MHz. Experiments show that the sensor designed in this scheme can meet the measurement requirements under high-frequency current, and has reference value for high-frequency transient current measurement.