Extended Space Vector Control method for seven level inverter driving a winding excited synchronous machine

Abstract

In this paper Space Vector Control (SVC) method is used to drive a high voltage, high power synchronous machine with a seven level cascaded H bridge inverter. The synchronous machine is the generator of one of Rey gas turbine power plant units. In low speeds in which voltage of the inverter is low, the seven level inverter operates in three level mode. In all operational speeds the modulation method remains the same. So use of SVC method, which is thought to be only useful for multilevel inverters of more than seven levels, is extended to three level inverters which is due to appropriate control system. Simulation results verify effectiveness of the control strategy for the designed inverter over a wide range of machine speed.