Space vector modulating method of three-phase matrix converter

Abstract

The invention discloses a space vector modulating method of a three-phase matrix converter, which comprises the following steps: computing the amplitude values of the space vectors of the input voltage and the output voltage, computing the relative position angles of the sectors of the space vectors of the input current and the output current, computing the sector numbers of the space vectors of the input current and the output current, and computing the voltage modulation factor of the matrix converter; computing the duty ratio or the duration time of five switch states, and determining the five switch states and the modulation sequence in a modulation period according to the sector number of the space vector of the input current and the sector number of the space vector of the output voltage; and arranging the switches of the matrix converter to be switched on and switched off by a conversion control circuit according to the modulation sequence and the duty ratio or the duration time, thereby realizing conversion control. The invention does not adopt the method of compensation or control for compensating or controlling the distortion of output waveforms, thus an additional control circuit is not needed, and only the modulation factor of the space vector needs to be adjusted, so that the method is simple and easy.

Description

technical field [0001] The invention belongs to the technical field of AC power conversion devices, and in particular relates to a space vector modulation method of a three-phase matrix converter, so as to solve the problem of output voltage distortion of the matrix converter caused by grid voltage abnormal working conditions. Background technique [0002] The three-phase matrix converter 1 is composed of nine bidirectional power switches 2 in the form of a 3×3 switch matrix, such as figure 1 shown. where S i，j (i=A, B, C; j=a, b, c) represents a bidirectional power switch 2, each bidirectional power switch is composed of two insulated gate bipolar transistors (IGBT) with anti-parallel diodes using "common emission pole" structure. The input side of the matrix converter is the three-phase grid voltage 3, respectively with u a , u b , u c Indicates that there is an input filter 4 indirectly between the matrix converter and the power grid. The output sides of the matrix...

AI Technical Summary

Problems solved by technology

[0024] The purpose of the present invention is to provide a space vector modulation method for a three-phase matrix converter aiming at the deficiencies of the traditional space vector modulation technology, which solves the influence on the output waveform of the matrix converter when the grid voltage is abnormal , which realizes that the matrix converter can output three-phase sinusoidal symmetrical voltage or current waveform under normal and abnormal input voltage conditions

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