Variable-ratio magnetic potential comparison type transformer calibration system capable of self-calibration

Abstract

The invention discloses a variable-ratio magnetic potential comparison type transformer calibration system capable of self-calibration. The variable-ratio magnetic potential comparison type transformer calibration system comprises a magnetic potential comparison unit and a sampling adjustment unit, wherein the magnetic potential comparison unit comprises a standard input winding W0, a detected input winding Wx and a magnetic potential balancing core T; the magnetic potential comparison unit is used for inputting currents to a standard current transformer T0 and a calibrated current transformer TX, so as to generate secondary currents I20 and I2X separately; the secondary current I20 is input to the standard input winding W0, and the secondary current I2X is input to the calibrated input winding Wx, so as to generate magnetic flux on the magnetic potential balancing core T; the sampling adjustment unit comprises a detection winding WJ, an in-phase compensation winding WF, an orthogonal compensation winding WD, an adjustment conductor G, an adjustment capacitor C, and amplification control circuits D1 and D2; and the sampling adjustment unit is used for detecting unbalanced magnetic flux on the magnetic potential balancing core T, and balancing the magnetic flux on the magnetic potential balancing core T through amplifying compensation currents ID and IF output by the amplification control circuits D1 and D2.

Description

technical field [0001] The invention relates to the field of transformer calibration, in particular to a self-calibrating multi-ratio magnetic potential comparison type transformer calibration system. Background technique [0002] Transformer, also known as transformer, is a general term for current transformer and voltage transformer, which can convert high voltage / large current into low voltage / small current for application in measuring instruments, protection equipment and automatic control equipment. Due to the existence of certain errors in current or voltage transformers, it is necessary to use a transformer calibrator to verify the technical performance of current or voltage transformers used in the field or in the laboratory. The widely used transformer calibrator is the difference-measuring calibrator. The principle of the difference-measuring type is to connect the secondary current of the standard transformer with the same transformation ratio and the secondary cu...

AI Technical Summary

Problems solved by technology

The disadvantage of the difference-measuring transformer calibrator is that the transformation ratio of the standard transformer and the tested transformer must be the same, so it is required to manufacture a series of standard transformers with various transformation ratios to meet the needs of the verification work. Leading to a significant increase in testing costs and workload

Its disadvantage is that the error of the transformer calibrator is directly superimposed on the error of the standard transformer, so that even if a standard transformer with a higher accuracy level is used, only a very low-level transformer can be verified. The error of the transformer calibrator limits the accuracy level of the testable transformer, thus limiting its application

At the same time, the self-error of this transformer calibrator needs to rely on external standards for verification, which brings a certain amount of work.

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