Switch loss dispersion and distribution modulating method for ANPC (active neutral-point-clamped) type three-level inverter

Abstract

The invention discloses a switch loss dispersion and distribution modulating method for an ANPC (active neutral-point-clamped) type three-level inverter. Two transient states O+out and O-out are added to switch states in a conventional PWM (pulse width modulation) method for an ANPC type three-level inverter, the transient state O+out is added in the conversion process when the state P is switch to the state O+, the transient state O-out is added in the conversion process when the state N is switched to the state O-, switch loss produced by active switch devices is dispersed, and turn-off loss and turn-on loss are borne by an outer switch and an inner switch respectively, so that switch loss of the active switch devices on the inner and outer sides is balanced.

Description

technical field [0001] The invention belongs to the technical field of power electronics, and more specifically relates to a switching loss dispersion and distribution modulation method of an ANPC (active neutral point clamp type) three-level inverter. Background technique [0002] Compared with two-level power inverters, multi-level inverters have shown better output voltage quality, lower switching loss, smaller dv / dt, and lower device power ratio. its superiority. The traditional neutral-point clamped three-level inverter (3L-NPC) is representative, but it has a major disadvantage—the power loss is unevenly distributed among semiconductor devices, so the output power and switching frequency of the inverter are affected by limit. To deal with this problem, an active neutral point clamped three-level inverter (3L-ANPC) is proposed, which is derived from the traditional NPC topology. [0003] The PWM modulation method of the prior art ANPC rectifier is proposed to balance...

AI Technical Summary

Problems solved by technology

At present, there are several methods as follows: 1) The traditional PWM strategy can be divided into two methods due to the different switching states in the zero-voltage state, but these two methods are not effective in improving the loss distribution; 2) Natural frequency multiplication The method is derived from the first two methods, and its performance is relatively mediocre, and the loss distribution is still not uniform enough; 3) The adjustable loss distribution modulation method, which can make the device loss evenly distributed within a fundamental wave period, but contains multiple One switching state and two commutation modes, which is not simple enough; 4) A single zero-state modulation method, which can obtain lower total loss, but the loss distribution is not uniform

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