Patent ID: 7495938
Filing Date: 2009-02-24
Classification: H02M

Abstract:
1. A three-level power conversion system, comprising: a DC connection for receiving or supplying DC electrical power, the DC connection comprising first and second DC terminals and first and second capacitors coupled in series between the first and second DC terminals, the capacitors being coupled at a common node; a multi-phase AC connection for receiving or supplying multi-phase electrical power, the AC connection comprising first, second, and third AC terminals, and a three-level switching network comprising: a switch control system providing the sets of switching control signals by space vector modulation to equalize the voltages across the capacitors in open-loop fashion during operation of the power conversion system; wherein the switch control system comprises an even-order harmonic elimination space vector modulation system coupled with the three-level switching network, the space vector modulation system providing the sets of switching control signals by space vector modulation according to an even-order harmonic elimination vector switching sequence ensuring half-wave symmetry at all times to balance the voltage at the common node.