Modeling And Simulation Of Metering Reference Standard Device Of60kA Heavy Direct Current

With more and more expansion and higher precision of heavy direct current (dc) inthe industrial and scientific research, the measurement of heavy direct current has been animportant part of the modern electrical information measurement technology. However,there are no unified standards of the measurement of heavy direct current at present. So, itis urgent to develop a high-precision dc high current measurement reference standard.This paper is based on the item of National Natural Science Foundation ofChina-Basic research of Energy metering of High power rectifier power supply(No.51177061).The main measurement methods of heavy direct current are discussed in the first partof this paper. And by comparing their advantages and disadvantages, the heavy directcurrent comparator is selected.Next, the working principle of the heavy direct current comparator based on magneticmodulation is introduced. The60kA metering reference standard based on the dual-loopcontrol system is developed. The dual-loop control system is formed by the feedbackcontrol system and the bias control system. More than90%of the direct current magneticpotential of the measured current is automatically balanced by the bias winding’s currentand the feedback winding’s current automatically compensates the rest of the dc magneticpotential. The hardware design of the whole system is discussed in this paper. Themodelings of all aspects of the system are set up. The transfer function of each part hasbeen deducted. The simulation of the system has been done with the help ofMATLAB/SIMULINK to analyse the stability and the error of the dual-loop controlsystem.At last, the self-calibrate and the mutual-calibrate of the60kA metering referencestandard for heavy direct current is introduced. And the results show that the current ratioaccuracy of the standard can reach as high as5×l0-6.