Patent ID: 7940537
Filing Date: 2011-05-10
Classification: H02M

Abstract:
1. A medium voltage drive system comprising: a plurality of power cells each to couple between a transformer and a load, wherein a first subset of the power cells each including an active front end are configured to provide power to the load and to perform partial regeneration from the load, and a second subset of the power cells are configured to provide power to the load but not perform the partial regeneration; and a controller coupled to the plurality of power cells to simultaneously control a DC bus voltage of at least one of the first subset of the power cells, correct a power factor of the system, and provide harmonic current compensation for the system, the controller including a digitizer to digitize voltage signals and current signals from an input to the transformer, input current signals to the active front end, and the DC bus voltage and provide the digitized information to a reference signal generator, the reference signal generator to generate reference signals to provide to a modulator, the modulator to provide gate signals to the active front end of each of the first subset of the power cells based on the reference signals.