The micro-current sensor is the key equipment for picking up the weak current signal. However, in practical applications such factors as temperature, humidity, strong electromagnetic interference, surge current, and run-time drift will change its phase characteristics, exerting a significant impact on phase-sensitive measurement, as in the case of the dielectric loss tan δ measurement for electrical equipment insulation online monitoring. To solve this problem, the FastICA algorithm is introduced in this paper. The field programmable gate array (FPGA) implementation of the phase self-calibration system for the micro-current sensor is proposed. The floating-point units are used in this implementation and the structure of the algorithm is optimized. The results show that the measuring precision, speed, and the fault-tolerant ability of the designed system meet engineering requirements. State Grid Electric Power Research Institute Press.
