Three-phase 18-pulse asymmetric Y-shaped output winding phase-shifting rectifier

Abstract

Disclosed is a three-phase 18-pulse asymmetric Y-shaped output winding phase-shifting rectifier. The three-phase 18-pulse asymmetric Y-shaped output winding phase-shifting rectifier includes a rectifier bridge and a three-phase 18-pulse asymmetric Y-shaped output winding phase-shifting rectifier transformer. The rectifier transformer is provided with a primary winding, a secondary winding and an iron core. Primary winding wiring is triangular, star-shaped, hexagonal or extended hexagonal. In the secondary winding, the phases each have a set of long side output winding which has the same numberof turns of each phase and are symmetrical and three-phase connected or not-connected and two sets of short side windings which have the same number of turns of each phase and are symmetrical, and the head end of each phase of the long side output winding is connected to the head ends of the other two phases of short side output windings or the tail end of each phase of the long side output winding is connected to the tail ends of the other two phases of the output windings to form three inequilateral Y-shaped windings. The primary winding and the secondary winding are arranged concentricallyor up-down on each phase of an iron core column and are wound after being insulated by metal foil or a conductor. The iron core is a three-phase iron core shaped like a Chinese character 'ri' or delta-shaped or three single-phase iron cores which are square-shaped, a shell type shaped like a Chinese character 'ri' or double-ring shaped shell type. The three-phase 18-pulse asymmetric Y-shaped output winding phase-shifting rectifier can be powered by a four-wire direct current system and is low in harmonic content and cost.

Description

technical field [0001] The invention relates to a three-phase rectifier, in particular to a three-phase 18-pulse asymmetrical Y-shaped output winding phase-shift rectifier. Background technique [0002] At present, in order to suppress the interference of the high-order harmonic current generated by the rectification device to the power grid, the multi-pulse phase-shifting rectification technology is often used. The main principle is to connect the secondary winding of the three-phase rectifier transformer into n-way (n-phase) AC output terminals with a certain phase difference, and connect it to the n-phase rectifier bridge, so that the current waveform in the DC output circuit of the rectifier bridge has 2n A pulsation waveform (abbreviated as pulse number). The higher the number of pulses, the smaller the AC component in the DC circuit, and the lower the high-order harmonic current content in the AC circuit on the primary side of the rectifier transformer. Theoretically...

AI Technical Summary

Problems solved by technology

Such a rectification device has many disadvantages: the number of transformers is large, the number of winding turns is large, the input voltage of the rectifier bridge is low, the conduction is discontinuous, the harmonic content of the AC side is high, and a balance reactor needs to be connected between each group of three-phase rectifier bridges. Many components, complex wiring, large volume, high cost, large loss, low efficiency, poor filtering effect, etc.

However, in these wiring methods, the discontinuous and unbalanced conduction of the rectifier bridge existing in the traditional rectifier device cannot be completely avoided, which will increase the harmonic content of the AC power supply side

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