Longitudinal differential protection current phase compensation method for YNd series transformer

Abstract

The invention relates to a longitudinal differential protection current phase compensation method for an YNd series transformer. The method is that TA secondary winding of the high-voltage side and TA secondary winding of the low-voltage side of the YNd series transformer are respectively connected through star connection, A phase current, B phase current and C phase current of the TA secondary winding of the Y side of the YNd series transformer are respectively switched in an A phase current loop, a B phase current loop and a C phase current loop of YNd11 or YNd1 transformer differential protection, and phase current of the TA secondary winding of the d side of the transformer is correspondingly switched in a phase current loop of the d side of an YNd11 or YNd1 wiring microcomputer transformer differential protection device when certain phase current of the d side of the transformer is the same as a certain phase current phase of the d side of a YNd11 or YNd1 transformer. The method is simple in principle and convenient to implement, completely conforms to a transformer differential protection current phase compensation principle, and can adapt to unusual YNd series transformer longitudinal differential protection current phase compensation of the transformers of various voltage levels.

Description

technical field [0001] The invention belongs to the relay protection control technology of electric power transmission and distribution network, and relates to a method for current phase compensation of longitudinal differential protection of YNd series transformers. Background technique [0002] Since the phases of the currents on each side of the transformer may be inconsistent, the transformer longitudinal differential protection (hereinafter referred to as the transformer differential protection) needs to perform current phase compensation. There are two methods of current phase compensation for transformer differential protection: 1. Traditional hardware phase shifting: for example, the secondary winding of Y-side current transformer (hereinafter referred to as TA) of YNd11 transformer adopts delta d-11 connection, and the secondary winding of d-side TA Use star Y-12 wiring; 2. Software phase shift: use software program and calculation formula to carry out current phase...

AI Technical Summary

Problems solved by technology

However, at present, the differential protection current software phase compensation method of various transformer protection manufacturers can only adapt to the YNd11, YNd1 and YNyn12 transformer wiring groups and their wiring combinations, and cannot adapt to the YNd3, YNd5, YNd7, YNd9 wiring groups and other wiring groups. Group and wiring combination, and no other literature gives a solution

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