Multi-level active neutral point clamp inverter series igbt voltage equalization circuit

Abstract

The invention belongs to the multi-level active neutral point clamping inverter technology, and specifically relates to a multi-level active neutral point clamping inverter series IGBT voltage equalization circuit, which is characterized in that it includes active neutral point clamping A single bridge arm of a five-level inverter and a converter; the single bridge arm of the active neutral point clamped five-level inverter includes a switch tube S1 and a switch tube connected in series between the positive terminal of the power supply and the negative terminal of the power supply S2, switch tube S4, switch tube S3, switch tube S3, switch tube S4, switch tube S2, switch tube S1; between the collector of switch tube S4 and the emitter of switch tube S4, switch tubes S5, Switch tube S6, switch tube S6, switch tube S5. For a single bridge arm of an active neutral-point clamped five-level inverter, a single-input, double-output isolated power supply is used to generate the clamping voltage of the IGBT in series, and the input-to-output ratio of the converter is 4:1:1. After the voltage, the IGBTs running in series can realize dynamic and static voltage equalization.

Description

technical field [0001] The invention belongs to the technical field of multi-level active mid-point clamp inverters, and in particular relates to a multi-level active mid-point clamp inverter series IGBT voltage equalizing circuit. Background technique [0002] In the field of high-voltage variable-frequency drive and high-voltage power distribution, the DC bus voltage of inverters continues to increase, especially in the fields of high-speed rail electric traction and ship electric propulsion, high-voltage inverters have strong application requirements. Limited by the voltage level of power devices, the traditional two-level inverter circuit can no longer meet the demand; and the diode-clamped or capacitor-clamped multi-level inverter is more suitable for application under three-level conditions. In more level working conditions, the circuit topology will be extremely complex; for H-bridge cascaded multi-level inverters, each H-bridge needs an independent DC power supply, a...

AI Technical Summary

Problems solved by technology

The traditional RCD snubber circuit used for IGBT voltage equalization will bring greater cost pressure and difficulty in structural layout setting on the one hand, and on the other hand will bring a certain amount of extra loss, which will affect the dynamic process of IGBT switching

The effect of the RCD snubber circuit in terms of dynamic voltage equalization is not ideal

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