Research On Z-source Indirect Matrix Converter

Compared with the AC-DC-AC type of power converters, the matrix converter asone type of the AC-AC power converters is of simple structure and of many idealperformances, which is considered as a new green power converter which has attractedmuch attention at home and abroad. First, an introduction is given, which include thebackground, purpose and meaning of the research work, a survey of the developmentand hotspots of matrix converter. At present, the two main drawbacks hindering theprocess of practical matrix converter are the lower voltage transfer ratio andbidirectional switches safe commutation. In order to solve the former problem, the paperconsiders introducing the Z-source network into the matrix converter. The newconverter can improve the voltage transfer ratio through the shoot-through state ofZ-source network.Based on the theoretical analysis of the three-phase Z-source inverter, the paperconstructs a three-phase Z-source two stage matrix converter. The analysis of theZ-source matrix converter, as well as its rectification stage and the inverter stagemodulation strategy are discussed. At the same time, the relationship between thevoltage transfer ratio, boost factor and modulation index is revealed.For the multi-phase machine drive system, the three-to-five phase indirect matrixconverter is deeply researched, which include the modulation strategy and the voltagetransfer ratio. Based on the discussion of the matrix converter’s common-mode voltage,the paper presents a novel method which can successfully reduce the common-modevoltage to86.67%. As the same as the three-phase Z-source matrix converter, thefive-phase Z-source matrix converter is researched. The modulation strategy and thevoltage transfer ratio are presented in the paper.The paper designs the switch circuits of matrix converter, including input filtercircuit, switch protecting circuit and signal conditioning circuit. The logic control ofbi-directional switches’ four-step commutation is realized using programmable logicdevice.The validity of major conclusions drawn in this paper is demonstrated by theMATLAB. At present, many valuable results acquired in experiment establish stabilitybasis for future research of matrix converter.