Method of testing transformer before commissioning of intelligent substation

Abstract

The invention discloses a method of testing a transformer before commissioning of an intelligent substation. A primary circuit at a low-voltage side of an outdoor transformer is firstly short-circuited, AC0-220 voltage is connected into a primary circuit at a high-voltage side of the outdoor transformer phase by phase, and thus certain AC values are generated on corresponding primary phases at the low-voltage side and the high-voltage side of the outdoor transformer; according to the main wiring mode of the outdoor transformer, a transformer bushing CT secondary wiring mode and transformer CT transformation ratio parameters, in a main control room of an indoor substation, bushing CT secondary current at the high-voltage side of the indoor transformer and bushing CT secondary current at the low-voltage side of the indoor transformer are correspondingly measured phase by phase according to the connection phase of the primary circuit at the high-voltage side of the outdoor transformer, and finally according to current phase values tested on phases, a transformer hexagonal diagram is drawn, and a testing result is analyzed and obtained. The method of the invention has the advantages that the testing precision is high; the testing speed is fast; the testing error probability is greatly reduced; testing can be directly carried out before commissioning; and the transformer can be effectively ensured to operate stably and safely.

Description

technical field [0001] The present invention relates to the technical field of testing methods for electric equipment, and more specifically relates to the technical field of testing methods for transformers. Background technique [0002] According to regulations, when a new transformer is put into operation, the hexagonal diagram of the transformer must be tested to detect the correctness of the transformer wiring during installation, so as to ensure the safe and reliable operation of the transformer. At present, the traditional test method is to draw a hexagonal diagram by measuring the amplitude and phase of the operating load side current after it is put into operation. Through the analysis of the hexagonal diagram, a conclusion can be drawn whether the transformer is installed correctly or not. This kind of testing method exists The disadvantage of this method is that it can only be measured after the transformer is put into operation, and it must be measured after exit...

AI Technical Summary

Problems solved by technology

At present, the traditional test method is to draw a hexagonal diagram by measuring the amplitude and phase of the operating load side current after it is put into operation. Through the analysis of the hexagonal diagram, a conclusion can be drawn whether the transformer is installed correctly or not. This kind of testing method exists The disadvantage is that it can only be measured after the transformer is put into operation, and it must be measured after exiting the differential protection. The measurement accuracy is not high and errors are prone to occur.