Matrix converter comprising source damping filtering unit, and control method thereof

Abstract

The invention discloses a matrix converter comprising a source damping filtering unit. The matrix converter comprises an input power source, an LC input filtering unit, a switch matrix and a microprocessing unit. Currents provided by the input power source are input to a load successively through the LC input filtering unit and the switch matrix, the microprocessing unit, through control over the resonance damping of an LC filter, controls input current waveforms of the LC filter so as to obtain expected output voltages, and according to the expected output voltages, distributes pulses to each switch tube in the switch matrix to control the work state of each switch tube in the switch matrix. The invention also provides a control method of the matrix converter comprising the source damping filtering unit. The dynamic characteristic is improved, the power supply current harmonic wave content can be reduced, a power supply side is enabled to be always close to a unit power factor, and the efficiency of the matrix converter is improved. At the same time, resonance appearing in the LC filter is effectively inhibited, the total harmonic wave distortion rate of power supply currents is reduced, and the influence exerted by the matrix converter on a power network is decreased.

Description

technical field [0001] The invention relates to a matrix converter, in particular to a matrix converter with an active damping filter unit and a control method thereof. Background technique [0002] The main purpose of adding an LC filter to the input side of the matrix converter is to meet the requirements of electromagnetic compatibility and prevent the input end of the matrix converter from entering the power grid due to the burrs caused by the high-frequency switching of the switching device; filter out high-frequency voltage components in the power grid. , so as not to affect the output quality of the matrix converter. However, the LC filter is a second-order underdamped system. When the system contains harmonics close to the resonant frequency of the LC filter, the input current will be seriously disturbed, and even the system will not work properly. When analyzing the input filter of the matrix converter, on the premise that the three-phase input voltage is balanced ...

AI Technical Summary

Problems solved by technology

However, these two methods can only improve the dynamic characteristics and suppress resonance, but cannot guarantee the unity power factor of the input side

There are also literatures that use PID controller instead of PI controller to increase the damping of the system. This method suppresses resonance and ensures unity power factor at the same time, but it will increase high-frequency noise.

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