A method of calibrating the relative error of 90-degree phase angle

Abstract

The invention provides a method for calibrating a 90-degree phase angle relative error. The method comprises steps of establishing a first alternating current voltage and a second alternating current voltage which are identical in amplitude and opposite in phase; applying the first alternating current voltage on one input end of a first anti-phase adder through a first 90-degree phase shifter and a second 90-degree phase shifter, and applying the first alternating current voltage on the other input end of the first anti-phase adder, so as to measure a first output voltage of the first anti-phase adder; applying the first alternating current voltage on one input end of a second anti-phase adder through the first 90-degree phase shifter, and applying the second alternating current voltage on the other input end of the second anti-phase adder through the second 90-degree phase shifter, so as to measure a second output voltage of the second anti-phase adder. According to the first alternating current voltage, the second alternating current voltage, the first output voltage and the second output voltage, the phase relative errors of the first 90-degree phase shifter and the second 90-degree phase shifter are obtained. The phase error is high in accuracy, and requirements for high precision calibration can be met.

Description

technical field [0001] The invention relates to the field of metrology and testing, in particular to a method for calibrating the relative error of a 90-degree phase angle. Background technique [0002] Phase is an important metering parameter. The measurement of many electrical parameters is directly related to phase, and many non-electrical measurements are also converted into phase angle measurements. [0003] In precision electromagnetic measurement, the resistive or capacitive voltage divider, voltage transformer, etc. used to measure AC voltage, and the shunt, current transformer, etc. used to measure AC current, all have certain phase errors. The phase error will affect the measurement accuracy, especially in the measurement circuit with low power factor, the phase error has a significant impact on the measurement accuracy. [0004] When calibrating a phase measuring instrument, a standard phase source is usually used. In some occasions where the measurement accurac...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a method for calibrating the relative error of the 90-degree phase angle to solve the problem that the accuracy of the phase angle obtained by the existing method is low

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