High-power converter grounding method for fully-through flexible AC traction power supply system

Abstract

The invention discloses a high-power converter for a fully through-type flexible AC traction power supply system, which is suitable for a system solution in which an input transformer and an output transformer are present to isolate the power grid and the contact network. A common topology structure includes an input transformer, an AC-DC-AC multiplexer, and an input transformer. Level converter and output transformer, when a ground fault occurs in the converter link of the fully-through flexible AC traction power supply system, if there is more than one operating traction converter station on the contact network, the grounding method selected by the present invention can be effective It suppresses the overcurrent and overvoltage conditions of each component and hardly affects the power supply voltage of the contact network. At the same time, it can be quickly and accurately identified and cleared by the protection system.

Description

Technical field [0001] The invention relates to the technical field of rail transit traction power supply, and in particular to a grounding method for a high-power converter of a fully through-type flexible AC traction power supply system. Background technique [0002] The electrical phase separation in the traditional railway traction power supply method seriously restricts the safe and reliable operation of high-speed and heavy-haul trains. It also brings increasingly prominent power quality problems such as negative sequence and harmonics to the external power grid. [0003] The fully through-type flexible AC traction power supply technology realizes complete decoupling of the power supply network and the contact network through multi-level converter technology, which can completely eliminate electrical phase separation on the entire line, improve the power supply quality, power supply reliability and power supply capacity of the contact network, and The fault ride-throug...

AI Technical Summary

Problems solved by technology

Grounding methods include direct grounding, grounding through resistance or arc suppression coil, among which, grounding through resistance or arc suppression coil can effectively suppress the fault current, and grounding through arc suppression coil can also overcompensate the distributed capacitance current, but distributed capacitance The parameters are inaccurate and difficult to obtain in the design stage, so the parameters of the arc suppression coil often need to be adjusted according to the actual situation on site

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