A 60,000-A DC comparator based on dual-loop control system

A 60,000-A dc comparator based on dual-loop control system with self-calibration and mutual-calibration is developed. The dual-loop control principle, which is that the bias winding´s current automatically balances more than 90% of the dc magnetic potential of the measured current and the feedback winding´s current automatically compensates the rest of the dc magnetic potential, is applied in this comparator. The quadruple electricity and magnetic shielding structure is used to get a high precision, which can reach 5×10^-6 accuracy. It has been verified by experiments. Finally, the advantages and bright application prospects are shown in detail.