Three-level inside and outside tube voltage sharing control method for three-level inverter

Abstract

Provided is a three-level inside and outside tube voltage sharing control method for a three-level inverter. The method aims at a diode clamp type three-level inverter circuit. The method is characterized in that in the process of generating driving signals of a first switch tube, a second switch tube, a third switch tube and a fourth switch tube, when switching of the switch tubes from 0,0,1,1 to 1,1,0,0 and switching from 1,1,0,0 to 0,0,1,1 are recognized, a section of transition signals is inserted into the driving signals of the first switch tube, the second switch tube, the third switch tube and the fourth switch tube forcedly and respectively. The corresponding states of the transition signals are that the first switch tube is disconnected, the second switch tube is connected, the third switch tube is connected and the fourth switch tube is disconnected, namely 0,1,1,0. By means of the method, the problem that inside and outside tubes of a zero crossing point of the diode clamp type three-level inverter circuit do not share voltage is well solved.

Description

Technical field [0001] The invention relates to the technical field of electronic circuits, in particular to a three-level internal and external tube voltage equalization control method of a three-level inverter. Background technique [0002] With the increasing shortage of traditional energy, the development of new energy has attracted more and more attention. Solar energy is an important part of new energy. In recent decades, the development of solar inverters has become faster and faster, and more and more problems have been encountered in the development process. Nowadays, the three-level topology is widely used in solar inverters. The output harmonics are small, and the efficiency is high. [0003] In a three-level inverter, the typical diode clamped three-level inverter main circuit is figure 1 As shown, it mainly includes DC voltage divider capacitors C1 and C2 and a diode-clamped three-level bridge arm. The diode-clamped three-level bridge arm includes two clamp diodes D1,...

AI Technical Summary

Problems solved by technology

[0006] The purpose of the present invention is to provide a three-level inner and outer tube pressure equalization control method of a three-level inverter, which can effectively solve the problem of uneven pressure on the inner tube and outer tube that may occur on the three-level bridge arm

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