Electrified railroad homo-phase traction power supply system

Abstract

The invention discloses an electrified railroad homo-phase traction power supply system. A traction transformer (SS1) of a traction substation is a three-phase-two-phase transformer; three phases (A, B and C) of the primary side of the traction transformer (SS1) are connected with a public power grid; a voltage reduction transformer (G), a first single-phase current transformer (M1), a direct-current capacitor (C) and a second single-phase current transformer (M2) are connected between an alpha output phase and a beta output phase of the secondary side in turn; the alpha phase supplies power to a locomotive (L), and the output voltage of the alpha phase is 27.5kV; and the output voltage of the beta phase is between 600 and 2,000V. The system can implement two-arm homo-phase power supply of the railroad traction substation without split phase, reduces the split phase link, is favorable for high-speed, stable and safe operation of the railroad, and has the advantages of simple structure, low cost and convenient implementation.

Description

technical field [0001] The invention relates to a same-phase power supply system for electrified railways Background technique [0002] The single-phase system has the advantages of simple structure, low construction cost, convenient operation and maintenance, etc., which determines that single-phase power frequency AC power is generally used to power railway locomotives in electrified railways. But at the same time, in order to ensure the three-phase balance of the public power system and reduce negative sequence and reactive power, the electrified railway cannot directly use single-phase power supply, but the traction transformer in the traction substation must adopt three-phase incoming lines and alternate phase-commutation output power supply. Way. When a three-phase-two-phase traction transformer is used in the traction substation, the two phases of the transformer output the α phase and the β phase, which supply power to the uplink and downlink power supply arms respe...

AI Technical Summary

Problems solved by technology

[0004] The existence of the excessive phase separation process has brought a series of problems to railway transportation: 1. There is a power outage process during the excessive phase separation process. In the neutral section, the locomotive runs by inertia, so that the train loses power in a short time and the speed decreases. The impact is even greater on long ramps and outbound sections; especially for high-speed, heavy-duty transport locomotives, it may even cause abnormal parking of trains

2. Under high-speed operating conditions, although the automatic over-current phase-splitting device does not require manual intervention, its accuracy and reliability are not high due to high working voltage and frequent switching operations, which also seriously affect the safe operation of the locomotive.

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