A method and system for controlling a three-phase drive connected to a three phase power source. The method includes connecting a converter to transfer power from the power source to a first direct current (DC) bus, where the converter and the first DC bus each have a neutral common point (NCP). Connecting a second DC bus to the first DC bus and configuring an inverter connected to the second DC bus to draw power from the second DC bus to provide a plurality of motor signals, the inverter having an inverter NCP. The method also includes connecting a neutral point selection device to the first DC bus NCP and selectively connecting to the converter NCP or the inverter NCP, the bus selection device configured to disconnect the converter NCP or the inverter NCP from the first DC bus NCP under selected conditions.