Development of on-site calibration system of electronic current transformer with digital output

Traditional current transformer is being replaced by electronic current transformer in power system and other industrial field. Nevertheless, the use of power supply circuit and signal processing circuit brings new challenge to the stability of electronic current transformer, so the calibration and monitoring of electronic current transformer is more important. We presented a calibration system based on a virtual instrument, which can calibrate the electronic current transformer with digital output on site. The experimental results show that this system has high precision to meet the requirements of calibrating 0.2 s class electronic current transformer.