Transformer winding deformation intelligent detection method based on sweep frequency impedance curve identification

Abstract

The invention discloses a transformer winding deformation intelligent detection method based on sweep frequency impedance curve identification. A short-circuit impedance method and a frequency response analysis method are combined, a transformer winding equivalent circuit model is established and acquisition of a transformer winding sweep frequency impedance curve is performed; the method comprises the following steps: under the condition that a sampling resistor R and a voltage U of the sampling resistor R are known, a current I flowing through a winding can be obtained through a formula I =U / R, and a sweep frequency impedance method wiring mode which effectively combines a short circuit impedance method and a frequency response analysis method can be obtained; during testing, one side of a transformer winding is short-circuited by using a wire, and sine sweep signals with the frequency of 10Hz-1MHz are injected into the head end of the transformer winding on the other side; and theresistance values of sampling resistors RC1 and RC2 in the test system are 50 omega, so that the current flowing through the non-short-circuited side is shown in the description. According to the invention, the transformer winding deformation is intelligently detected according to the change condition of the element parameter value, the situation that the transformer winding deformation excessively depends on experienced professionals is avoided, the analysis conclusion is unified, and great convenience is brought to the maintenance decision.

Description

technical field [0001] The invention relates to the technical field of transformer winding detection, in particular to an intelligent detection method for transformer winding deformation based on frequency-sweeping impedance curve identification. Background technique [0002] Transformer is one of the important electrical equipment in the power system, and its safe operation is of great significance to ensure the safety of the power grid. According to relevant statistics, transformer winding is the main part of transformer accident damage. Poor short-circuit resistance of transformer windings is the main cause of transformer damage. With the continuous increase of power grid capacity, the gradual establishment of ultra-high voltage and ultra-high voltage power systems, and the imminent formation of complex systems such as large-capacity, large-scale interconnection, and west-to-east power transmission, the safe operation of the power system and the reliability of power supp...

AI Technical Summary

Problems solved by technology

However, this purely empirical method has obvious shortcomings: 1) The experience requirements for analysts are high, and it is difficult to be competent without experience or insufficient experience; 2) Due to the dispersion and uncertainty of experience, it is difficult to standardize and promote. analysts may draw different analysis conclusions, which brings certain difficulties to maintenance decision-making

This method is not feasible

The main reasons are: 1) The accuracy of judgment is low; 2) It cannot accurately reflect the specific changes in the frequency and amplitude of the extreme points of the frequency sweep curve

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