System and method for calibrating angle difference of current sensor

Abstract

The invention presents a system and a method for calibrating the angle difference of a current sensor. The method comprises the following steps: a voltage and current signal source outputs a measurement voltage signal and an excitation current signal, a current sensor to be calibrated generates a measurement current signal in response to the excitation current signal, and the measurement voltage signal and the measurement current signal are kept at the same frequency at some calibration frequency points; a voltage and current measuring instrument collects signals to complete the measurement ofphase points needing to be calibrated at the calibration frequency points; the average phase delay value of each calibration frequency point is calculated according to the input voltage and current phase difference value and the measured voltage and current phase difference value of the current sensor to be calibrated, and then, the average phase delay value of all the calibration frequency points is obtained; operation is carried out to obtain an over-determined equation group; and the over-determined equation group is solved to obtain the angle difference calibration parameters of the current sensor to be calibrated, and the angle difference is calibrated according to the angle difference calibration parameters. The problem that the precision of current measurement by a current sensor is poor due to angle error is solved.

Description

technical field [0001] The invention relates to the field of measuring instruments, in particular to a system and method for calibrating an angle difference of a current sensor. Background technique [0002] In instruments with current measurement functions such as ammeters and power measuring instruments, current sensors must be used to measure large currents that exceed the measurement range of the instrument. However, due to its working principle, the current sensor will generate an angle difference between the input current (measured current) and the output current, and the angle difference directly affects the measurement accuracy of power measurement instruments. [0003] Since the measured angular difference of the current sensor has an important impact on power measurement and fault diagnosis, it is necessary to calibrate the angular difference of the current sensor. Most of the current angular difference calibration methods use the ergodic frequency and range metho...

AI Technical Summary

Problems solved by technology

[0004] The angular difference calibration system and method of the current sensor of the present invention solves the technical problem of insufficient current accuracy and power measurement accuracy caused by the angle error introduced by the current sensor when the instrument with the current measurement function uses the current sensor to measure the current

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