The toroidal core was excited by sharp pulse current. The sensor circuit is composed of peak value detector, Butterworth low-pass filter and differential amplifier.
磁芯采用高频脉冲电流励磁，信号处理电路由峰值检波、低通滤波及差动电路构成。
2
This paper introduces a kind of electric circuit which mainly consists of a peakdetector and a pulse-width discriminator for protecting the three-phase alternating-current supply with loses a phase.