Method for improving the mode of operation of a matrix converter

Abstract

A method for operating a matrix converter in which m phases of a generator generating alternating voltage with n (n<m) phases of a load are alternatingly connected via a multiple number of controllable bi-directional switches arranged in an (m×n) matrix, wherein switching over from a selected connected phase of the generator to a selected non-connected phase of the generator takes place in a controlled sequence of commutation instants of the individual switches. While being able to use low commutation frequencies and correspondingly low commutation losses adapted, improved target voltage curves or target spectra of the generated alternating voltage can be obtained by (1) calculating the output spectrum of the matrix converter based on the connectivity of the phases, on the phase relationship between input and output, and on the instants when commutations of the switches are initiated and/or on the instants when commutations of the switches are completed, by (2) assessing the influence of individual commutations or groups of commutations based on calculated deviation output spectra for deviated individual commutations or groups of commutations, and by (3) amending the sequence of commutation instants to the target voltage curve or target spectrum using the information of these calculated deviation output spectra.