Method for automatically correcting series side voltage sampling polarity of in-phase power supply device

Abstract

The invention provides amethod for automatically correcting the series side voltage sampling polarity of an in-phase power supply device. According to the method, the in-phase power supply device is operated to carry out pre-charging and open-loop voltage outputting processes, the polarity of PT voltage sampling signals of an incoming switch cabinet is automatically corrected according to the PT voltage sampling signals of a starting cabinet and the incoming switch cabinet, and the polarity voltage is used in control, it is ensured that the polarity of the voltage output by the series side of the in-phase power supply device is matched with the voltage (T seat voltage) of the incoming switch cabinet, and the problem of overcurrent caused by the fact that the output voltage of the converter is opposite to the incoming line voltage is avoided. The invention provides the method for judging the sampling directions twice in the automatic correction process of the series side voltage sampling polarity, and the method is simple and effective. In the process of carrying out polarity judgment twice, the situation that the sampling polarities are not opposite or different due to the fact that the sampling coefficients are set mistakenly can be found.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to a method for automatically correcting the polarity of voltage sampling on the series side of an in-phase power supply device. Background technique [0002] Electric locomotives are single-phase electric loads. In order to reduce the impact of negative-sequence current on the power system, the traction network power supply adopts measures such as phase separation and partition, rotation of phase sequence, and an electric phase separation link is added to the catenary. The automatic over-phase separation device not only has frequent actions, short life and low reliability, but also causes loss of train speed and traction. The same-phase power supply device solves the problems of electric phase separation, voltage fluctuation, low power factor and negative sequence current exceeding the standard in the traction substation. [0003] The common-phase power supply device is ...

AI Technical Summary

Problems solved by technology

[0006] Although the existing technical solutions can also determine the direction, there is a problem of time-consuming and labor-intensive manual line checking

In addition, although the sampling direction of the T-seat voltage of the same-phase power supply device is correct using the relay tester, there may also be errors in the wiring of the main circuit, and the problem that the output voltage of the series side is reversed from the T-seat voltage may also occur.

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