Space Vector Modulation for a 4-Leg Matrix Converter

Abstract

THIS thesis covers the investigation into the use of Space Vector Modulation for the control of a 4-leg matrix converter, which is capable of providing a 3-phase plus neutral supply from a standard balanced 3-phase source. Traditional 3x3 matrix converters have limited use in this application as they are only capable of supplying a balanced three-phase load. It would be desirable to be able to power unbalanced and nonlinear loads, requiring that the converter provides a neutral connection. As with voltage source inverters, this goal can be achieved by extending the number of output legs in the matrix converter to four. In this thesis, a new Space Vector Modulation technique is proposed for this 4-leg, or 3x4, matrix converter. This technique is an extension of the method currently in use on 3x3 matrix converters, and so it allows the de-coupled control of both the input and output. The thesis then goes onto cover the build of a demonstration converter, looking at the different aspects which make up a converter, to finally go on to prove the theory, and a set of results are presented to validate this.ii

Research on space‐vector modulation and common‐mode voltage of four‐leg matrix converter

“…The modulation method in this work is SVM. SVM method for a four‐leg MC is firstly introduced in [2]. Compared to traditional SVM method for three‐leg MCs, the output voltage space of the new method is extended to 3D while the input current space remains the same There are 45 switching states used in the SVM method.…”

“…Mason et al [2] proposed a four‐leg MC using space‐vector modulation (SVM) method in 2005. In 2010, Crdenas et al [3] give its experimental validation.…”