In-phase power supply scheme for electrified railway based on uncontrolled rectification and ladder wave synthesis inverter

Abstract

The invention provides an electrified railway cophase power supply scheme based on uncontrolled rectification and step wave synthesis inversion, and belongs to electrified railway cophase power supply schemes. [System]: An input end of a phase-shifting transformer is electrically connected with a three-phase high-voltage alternating current, an output end of the phase-shifting transformer is connected with a three-phase uncontrolled rectifier, and the three-phase uncontrolled rectifier is connected with a single-phase inverter through a filtering capacitor; a DC accumulator is connected between the filtering capacitor and the single-phase inverter, and the DC accumulator provides interfaces for accessing other energies; and output ends of the single-phase inverter are respectively connected with an uplink overhead line system and a downlink overhead line system. [Method]: An inversion side performs step wave synthesis modulation, and phase information of all traction substation is provided by a GPS synchronous clock; the uplink and downlink overhead line systems are in a parallel operation state; and a proper number of energy storage batteries are disposed in a DC filtering link, residual regenerated energy when a small probability event that brake power is greater than traction power occurs is cached, and interfaces for introducing the other energies are provided. [Advantages]: the scheme has the advantage of mutual standby, and capacity investment is saved.

Description

technical field [0001] The invention relates to an electrified railway in-phase power supply scheme, in particular to an electrified railway in-phase power supply scheme based on uncontrolled rectification and step wave synthetic inverter. Background technique [0002] Electrified railways are rapidly developing around the world due to a series of advantages such as fast running speed, strong carrying capacity, energy saving and environmental protection. Electric locomotives, as a high-power single-phase AC work, harmonics and negative sequence. [0003] In the traditional traction power supply system, the three-phase-two-phase traction transformer converts the 110kV (or 220kV) three-phase high voltage into a two-phase 27.5kV voltage and connects it to the catenary. In order to reduce the impact of negative sequence on the public power grid, it is often connected to the high-voltage power grid by means of segmented power supply and phase sequence rotation. The phases of the...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide an electrified railway in-phase power supply scheme based on uncontrolled rectification and ladder wave synthesis inverter, to solve the problems of large switching loss, high cost and low reliability in the current electrified railway in-phase power supply scheme

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