Error measurement apparatus and measurement method for current transformer

Abstract

The invention provides a current transformer error measurement device and measurement method, the device includes a power generator (1), a reference standard (2) and an error tester (3), the power generator (1) generates a large Current AC/DC composite signal or sine half-wave signal, and the generated signal is respectively applied to the measured current transformer (4) and the reference standard device (2); the reference standard device (2) can convert the measured large current signal The AC and DC components in the AC and DC components are accurately converted into small current or small voltage signals, and the small current or small voltage signals are input to the error tester (3) as a reference signal; the error tester (3) outputs the reference standard (2) The reference signal and the measured signal output by the measured current transformer (4) are synchronously sampled, converted and calculated to obtain a measurement result.

Description

technical field [0001] The invention relates to the field of electrical measurement, in particular to a current transformer error measuring device and a measuring method. Background technique [0002] Current transformer is the key equipment for electric power production, electric energy measurement and protection. In the process of power production, a large number of current transformers are used in power generation, power transformation and other links to measure and protect high-voltage and high-current electric energy. If there is a DC component in the primary current in the power grid, the iron core of the current transformer in the electric energy metering device will be magnetized, and the greater the magnetizing current, the greater the residual magnetism. In the case of no demagnetization, the residual magnetism can be kept until the next magnetization process. The influence of residual magnetism on the error of current transformer can be reflected in the magnetiz...

AI Technical Summary

Problems solved by technology

The general transformer calibrator adopts the principle of differential balance comparison. The advantage of this kind of calibrator is its high accuracy, and its resolution can reach 1×10-8. It can be used to calibrate transformers of 0.0001 level and below. The disadvantage is that this kind of calibrator needs manual adjustment, it is difficult to check zero balance, and it is inconvenient to use

Although the working efficiency of the latter is higher than that of the traditional electrical calibrator, the circuit is complex and difficult to debug. When the differential signal is small, the m

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