Double-switch three-level rectifier with symmetrical T-shaped bridges

Abstract

A double-switch three-level rectifier with symmetrical T-shaped bridges comprises two groups of symmetrical T-shaped bridges and two split capacitors C1 and C2. Three bridge arms of the two groups of T-shaped bridges are respectively composed of two diodes and a group of bidirectional power tubes; the first T-shaped bridge comprises diodes D1, D2, D5, D6, D7 and D8 and a power switch tube S1, wherein the diodes D5, D6, D7 and D8 and the power switch tube S1 form a group of bidirectional power tubes. The second T-shaped bridge comprises diodes D3, D4, D9, D10, D11 and D12 and a power switch tube S2, wherein the diodes D9, D10, D11 and D12 and the power switch tube S2 form a group of bidirectional power tubes. The two groups of symmetrical T-shaped bridge structures are favorable for solving the heat dissipation problem and the modular design of the system. According to the invention, the three-level function is realized by adopting different combination modes of the power switch tubes, and even if a bidirectional tube is in a fault state, the double-switch three-level rectifier with the symmetrical T-shaped bridges can still realize power output to a direct current side.

Description

Technical field[0001]The present invention relates to the field of single-phase three-level rectifier, and more particularly to a dual-switched three-level rectifier of a symmetrical T-bridge.Background technique[0002]With the development of industry and economy, people's requirements for power converters are increasing, and more focused on the green environmental performance of the power converter. In particular, the introduction of the strict standards of the country, the power factor and the harmonic content have become a factor that must be considered when designing power electronics. The traditional two-level topology converter uses diode irregular rectification, resulting in severe current waveform distortion of the grid side, which brings severe harmonic pollution to the grid, and the power factor in this manner is low. At the same time, the two-level topographic converter is allocated to the bus voltage value on each power device, so this topology is not suitable for high pr...

AI Technical Summary

Problems solved by technology

However, the traditional two-level topology converter adopts the diode uncontrolled rectification method, which leads to serious current waveform distortion on the grid side, which brings serious harmonic pollution to the grid, and the power factor of the equipment in this mode is low

At the same time, the bus voltage distributed to each power device by the converter of the two-level topology is very large, so this topology is not suitable for high-voltage, high-capacity power applications

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