Patent attributes
An inverter circuit couples a DC voltage source having a primary side and a reference side to an electric motor or other AC machine having multiple electrical phases. An inverter circuit includes switches, diodes and a controller. For each of the electrical phases, a first switch couples the electrical phase to the primary side of the DC voltage source and a second switch couples the electrical phase with the reference side of the DC voltage source. For each of the first and second switches, an associated anti-parallel diode is configured to provide an electrical path when the switch associated with the diode is inactive. The controller is coupled to the switching inputs of each of the first and second switches and is configured to provide a control signal thereto, wherein the control signal provided to each switch comprises, in a low frequency mode, a first portion and a second portion, wherein the first portion comprises a first pulse width modulation scheme and the second portion comprises a second pulse width modulation scheme different from the first modulation scheme.
