Patent ID: 7881081
Filing Date: 2011-02-01
Classification: H02M

Abstract:
1. A power conversion system, comprising: a DC circuit comprising first and second DC current paths; an inverter comprising a multi-phase AC connection having a plurality of AC terminals for supplying AC electrical power, and a switching network comprising a plurality of switching devices individually coupled between one of the DC current paths and one of the AC terminals, the switching devices individually operable to selectively electrically couple the corresponding DC current path with the corresponding AC terminal according to a corresponding switching control signal; and a switch control system operative to provide the switching control signals by pulse width modulation at least partially according feedback signals or values representing AC phase outputs and according to the position of a reference vector in a space vector modulation diagram having a plurality of stationary active space vectors around the periphery of the diagram and two stationary zero vectors at an origin of the diagram, the vectors representing unique switching states for the switching network and defining a plurality of triangular sectors positioned around the origin, the sectors each being defined by a unique set of two active vectors and the zero vectors at the corners of the corresponding triangular sector, the switch control system providing the switching control signals according to a switching sequence corresponding to the diagram sector in which the reference vector is currently located, the switch control system comprising a common mode reduction component operative in each pulse width modulation period to determine max, mid, and min ones of the feedback signals or values, and to selectively adjust one or more feedback signals or values higher or lower to provide common mode compensated feedback signals or values having minimum differences therebetween based at least partially on a common mode dwell time.