Tractive power supply system based on cophase power supply

Abstract

The invention discloses a tractive power supply system based on cophase power supply, which comprises a traction transformer, a first isolating transformer, a second isolating transformer and a converter. A primary side of the traction transformer is connected with a public grid, a primary side of the first isolating transformer is respectively connected with a first power supply arm of the traction transformer and a backflow line of the tractive power supply system, a primary side of the second isolating transformer is respectively connected with a second power supply arm of the traction transformer and the backflow line of the tractive power supply system, and the converter is respectively connected with a secondary side of the first isolating transformer and a secondary side of the second isolating transformer. Three-phase balance of the primary side of the traction transformer, cophase power supply of the secondary side of the traction transformer, dynamic reactive power compensation of a traction network feeder and management of low-order harmonic of the tractive power supply system can be realized, and accordingly comprehensive management of electric energy quality of the traction transformer can be further realized.

Description

technical field [0001] The invention relates to the technical field of traction power supply systems for electrified railways, and more specifically, relates to a traction power supply system based on in-phase power supply. Background technique [0002] At present, the vast majority of electrified railways in the world adopt AC power supply system. The conversion of the three-phase high-voltage AC on the primary side to the two-phase low-voltage on the secondary side is completed through the traction transformer. Due to the non-symmetrical three-phase of the secondary side, the three-phase current of the primary side of the traction transformer is inconsistent. Symmetrical, so it is easy to generate negative sequence current on the primary side of the traction transformer, which will damage the traction transformer. Usually, the voltage amplitude and phase of the two adjacent power supply arms on the secondary side of the traction transformer are different, which may easily l...

AI Technical Summary

Problems solved by technology

[0003] In the traditional traction power supply system, the power factor of each power supply arm is determined by the load of the power supply arm or the locomotive running on the power supply arm. The AC locomotive with a higher power factor makes the power factor of the power supply arm higher, and the power factor is lower. The low DC locomotive makes the power factor of the power supply arm very low. In order to prevent fines caused by too low power factor, the traditional power supply system usually installs fixed capacitors, static var compensators SVC or static var Power generator SVG device is used to realize reactive power compensation, which increases system cost

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