Patent ID: 8373372
Filing Date: 2013-02-12
Classification: H02P

Abstract:
1. An electrical drive system comprising: a DC voltage supply; a capacitor connected in parallel with said DC voltage supply; an inverter circuit comprising a plurality of inverter switch pairs connected in parallel with said capacitor; one or more motor/generators coupled to the inverter circuit, the motor/generators defining two or more sets of stator windings, the plurality of inverter switch pairs are coupled to the sets of stator windings to form a plurality of inverter bridges coupled to each one of the sets of stator windings to provide an independent drive unit for each of the sets of stator windings; and a control circuit configured for generating control signals for the plurality of inverter bridges based on a plurality of modulation signals that have a phase shift with respect to each other and a plurality of carrier signals that have a phase shift with respect to each other, wherein each of the plurality of inverter switch pairs in each independent drive unit is associated with a different one of the plurality of modulation signals and each independent drive unit is associated with a different one of the plurality of carrier signals, and wherein the control circuit generates the control signals to close a positive switch of one inverter switch pair from the plurality of inverter switch pairs and open a negative switch of the one inverter switch pair if a signal value of a one of the plurality of modulation signals associated with the one inverter switch pair is greater than a signal value of the one of the plurality of carrier signals associated with the independent drive unit comprising the one inverter switch pair, else the control circuit generates the control signals to open the positive switch and close the negative switch.