Abstract: Circuits and methods for driving a load are disclosed. An exemplary driving circuit may include a plurality of switching devices and a controller electrically connected to the plurality of switching devices. The controller may be configured to provide a switching signal for controlling switching operations of the switching devices. The controller may also be configured to determine whether the switching signal falls within a predetermined dead zone. When it is determined that the switching signal falls within the predetermined dead zone, the controller may be configured to modify the switching signal by moving a space vector corresponding to the switching signal to a boundary of the predetermined dead zone. In addition, the controller may be configured to provide the modified switching signal to the switching devices.

Abstract: An inverter electrically operatively connects to a multi-phase electric machine, and a method for controlling the inverter includes executing a six-step mode to control the inverter and monitoring an electric voltage angle of the electric machine at a preset sampling frequency. When the electric voltage angle approaches a step transition associated with control of one of a plurality of switches of the inverter in the six-step mode, an intermediate duty command for the one of the switches is determined and a carrier signal is aligned based upon a present state of the one of the switches. The one of the switches is controlled employing the intermediate duty command and the aligned carrier.

Abstract: A voltage source inverter controller for controlling an inverter electrically connected to an electric machine includes a current command generator, a six-step flux controller and a current regulator. The six-step flux controller generates a flux modifier to regulate flux in a flux-weakening speed/load operating region of the electric machine when operating the electric machine in a six-step mode. The current command generator converts a desired torque to three-phase desired currents that are input to a dq0-dq transformer and combined with the flux modifier to determine a modified-flux direct-quadrature (dq) current request. The current regulator includes a proportional-integral feedback controller, anti-windup elements, a dq voltage limit element and a voltage magnitude limiter. The proportional-integral feedback controller and the anti-windup elements perform closed-loop current control on the modified-flux dq current request to determine commanded dq voltages.

Abstract: A voltage source inverter controller for controlling an inverter electrically connected to an electric machine includes a current command generator, a six-step flux controller and a current regulator. The six-step flux controller generates a flux modifier to regulate flux in a flux-weakening speed/load operating region of the electric machine when operating the electric machine in a six-step mode. The current command generator converts a desired torque to three-phase desired currents that are input to a dq0-dq transformer and combined with the flux modifier to determine a modified-flux direct-quadrature (dq) current request. The current regulator includes a proportional-integral feedback controller, anti-windup elements, a dq voltage limit element and a voltage magnitude limiter. The proportional-integral feedback controller and the anti-windup elements perform closed-loop current control on the modified-flux dq current request to determine commanded dq voltages.

Abstract: An inverter electrically operatively connects to a multi-phase electric machine, and a method for controlling the inverter includes executing a six-step mode to control the inverter and monitoring an electric voltage angle of the electric machine at a preset sampling frequency. When the electric voltage angle approaches a step transition associated with control of one of a plurality of switches of the inverter in the six-step mode, an intermediate duty command for the one of the switches is determined and a carrier signal is aligned based upon a present state of the one of the switches. The one of the switches is controlled employing the intermediate duty command and the aligned carrier.

Abstract: Methods and systems are provided for controlling an AC motor via an inverter. The method includes determining a delay-compensated offset based on a synchronous frame current, producing a current error based on a synchronous frame current and a commanded current, producing a voltage error based on an anti-windup offset and the current error, producing a commanded voltage based on the delay-compensated offset and the voltage error, and providing the inverter with the commanded voltage.

Abstract: Methods and systems are provided for controlling an AC motor via an inverter. The method includes determining a delay-compensated offset based on a synchronous frame current, producing a current error based on a synchronous frame current and a commanded current, producing a voltage error based on an anti-windup offset and the current error, producing a commanded voltage based on the delay-compensated offset and the voltage error, and providing the inverter with the commanded voltage.