A three-phase svc compensation device for traction side of electrified railway

Abstract

The invention relates to a three-phase static var compensator (SVC) device for an electrified railway traction side. The device comprises an SVC having a three-phase structure which is connected in a delta connection mode, wherein each phase comprises a thyristor controlled reactor subcircuit and a fixed capacity subcircuit which are connected in parallel; a power supply arm for the device comprises power supply arms a and b; tree phases of the SVC is connected between a and c (the power supply arm a and a steel rail c), between b and c (the power supply arm b and the steel rail c) and between a and b (the power supply arm a and the power supply arm b); and the device is connected to a low-voltage side of a traction transformer. The device can comprehensively realize functions of supporting power supply arm voltage, controlling a power factor, suppressing harmonic waves and compensating a negative sequence on electrified railway load; and the defect that a single-phase SVC on a traction side cannot compensate negative-sequence current can be overcome, a step-up transformer for an SVC on a power grid side can be saved, and the device is a three-phase SVC device which integrates advantages of the SVC on the traction side and the SVC on the power grid side.

Description

technical field [0001] The invention belongs to the field of electrified railway power supply, power electronics technology and power quality control, and specifically relates to a three-phase SVC compensation device used on the traction side of electrified railway. Background technique [0002] With the rapid development of electrified railways, the impact of electrified railways on the power quality of power systems has become a problem that cannot be ignored. On the one hand, since the traction power supply system of electrified railways in my country adopts single-phase power supply mode, and the electric locomotive is a single-phase load, no matter what wiring mode the traction transformer adopts, it will inject a large negative sequence current into the power system; on the other hand, Electric locomotives use power electronic converters, which will generate harmonic currents and inject them into the power system. In addition, because the load of the traction substatio...

AI Technical Summary

Problems solved by technology

According to the compensation requirements of electrified railway loads, each phase of the device can adopt an asymmetric design, which can comprehensively realize the functions of power supply arm voltage support, power factor control, harmonic suppression and negative sequence compensation for electrified railway loads; Phase SVC can not compensate for the shortcomings of negative sequence current, and the step-up transformer of grid side SVC can also be omitted. It is a three-phase SVC compensation device integrating the advantages of traction side SVC and grid side SVC.

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