Abstract: A propulsion system for a device includes an electric motor configured to generate torque to propel the device. The electric motor includes a stator and a rotor with one or more permanent magnets. A controller is in communication with the electric motor and has recorded instructions for a method for minimizing demagnetization in the one or more permanent magnets. The controller is adapted to select a starting point and an intermediate point on a current trajectory in a stator current graph. The controller is adapted to obtain a final point on the stator current trajectory based on a comparison of the intermediate point and a predetermined voltage limit. A demagnetized torque capability is generated based on the final point on the current trajectory.

Abstract: A method for increasing a default electric stall torque limits in a motor vehicle having an electrified powertrain inclusive of a traction power inverter module (TPIM) connected to an electric traction motor includes receiving vehicle level inputs via a controller. The controller is programmed with the default electric stall torque limits. The method includes selecting an inverter control strategy, via the controller, as a selected inverter control strategy in response to the vehicle level inputs, the strategy including temporarily increasing the default electric stall torque limits while applying a pulse width modulation (PWM) type at a corresponding PWM switching frequency. The method also includes controlling an output state of the TPIM and the electric traction motor over a calibrated duration, via the controller, using the selected inverter control strategy. A motor vehicle includes the controller, road wheels, TPIM, and traction motor.

Abstract: An electric drive system includes a rechargeable energy storage unit, a power inverter, an electric motor and a controller having a processor and tangible, non-transitory memory on which instructions are recorded. A transfer of electrical power between the rechargeable energy storage unit and the electric motor is governed by a pulse width modulation (PWM) switching frequency. The controller is configured to determine a current switching frequency based in part on a PWM type, a PWM switching frequency style and an inverter direct current voltage. A PWM scalar is determined based in part on the current switching frequency and a maximum value of a control reference frequency. The controller is configured to transmit a command signal to regulate the transfer of electrical power based in part on the PWM scalar, the PWM switching frequency being proportional to a product of the PWM scalar and the control reference frequency.

Abstract: A novel power inverter system for transferring electric power between a DC power source and a multi-phase electric machine is described, and includes a power inverter, a Z-source inverter, a first switch, and a second switch. The first switch is arranged between positive and negative conductors of a high-voltage bus that is electrically coupled to the DC power source, and the second switch is arranged in-line on the positive conductor of the high-voltage bus.

Abstract: An electric drive system includes a rechargeable energy storage unit, a power inverter, an electric motor and a controller having a processor and tangible, non-transitory memory on which instructions are recorded. A transfer of electrical power between the rechargeable energy storage unit and the electric motor is governed by a pulse width modulation (PWM) switching frequency. The controller is configured to determine a current switching frequency based in part on a PWM type, a PWM switching frequency style and an inverter direct current voltage. A PWM scalar is determined based in part on the current switching frequency and a maximum value of a control reference frequency. The controller is configured to transmit a command signal to regulate the transfer of electrical power based in part on the PWM scalar, the PWM switching frequency being proportional to a product of the PWM scalar and the control reference frequency.

Abstract: Presented are high-voltage electrical systems with optimized pulse width modulation (PWM) control, methods for making/using such systems, and vehicles with enhanced electric drive capabilities via PWM type and frequency control. A method of operating an electrical system includes an electronic controller determining a PWM region layout with multiple PWM regions arranged in a torque-speed curve calibrated to an electric motor and power inverter. The controller selects one of the PWM regions based on a speed and torque of the motor, and selects a PWM type based on this selected PWM region. The controller selects a PWM switching frequency style based on the selected PWM region, and selects a PWM switching frequency based on the selected PWM region, switching frequency style, and PWM type. The controller commands a power inverter to regulate transfer of electrical power between a rechargeable battery and the motor based on the PWM type and switching frequency.

Abstract: An apparatus and a method for controlling operation of a vehicle includes a controller having a processor and a tangible, non-transitory memory. The vehicle includes a park assembly with a park actuator motor having an actuator shaft. The vehicle has a park mode and an out-of-park mode. The controller is configured to determine if the park actuator motor has reached an out-of-park position when a shift command to the out-of-park mode is received. The controller is configured to obtain and store at least one dynamic parameter associated with the park actuator motor prior to the detent member reaching the out-of-park position. The method includes determining a load factor based on the dynamic parameter over time when at least one of a predefined time threshold and a predefined motor position threshold is reached. Operation of the vehicle is controlled based at least partially on the load factor.

Abstract: A method for increasing a default electric stall torque limits in a motor vehicle having an electrified powertrain inclusive of a traction power inverter module (TPIM) connected to an electric traction motor includes receiving vehicle level inputs via a controller. The controller is programmed with the default electric stall torque limits. The method includes selecting an inverter control strategy, via the controller, as a selected inverter control strategy in response to the vehicle level inputs, the strategy including temporarily increasing the default electric stall torque limits while applying a pulse width modulation (PWM) type at a corresponding PWM switching frequency. The method also includes controlling an output state of the TPIM and the electric traction motor over a calibrated duration, via the controller, using the selected inverter control strategy. A motor vehicle includes the controller, road wheels, TPIM, and traction motor.

Abstract: A method controls an electrified powertrain having an electric traction motor and a traction power inverter module (TPIM). A controller determines a current component capability and use case of the electrified powertrain. In response to the current component capability being less than a capability threshold and the use case matching a predetermined approved use case, the controller determines whether a predetermined margin exists in the component capability for operating the electrified powertrain in a maximum performance mode (MPM) for a full duration of a boosted driving maneuver. When the predetermined margin exists, the controller temporarily applies an extended inverter limit (EIL) of the TPIM to enable the MPM. The EIL allows operation of the traction motor to occur above default torque and speed operating limits for the full duration of the boosted driving maneuver. MPM/EIL availability is communicated to the operator.

Abstract: Presented are high-voltage electrical systems, control logic, and electric-drive vehicles with optimized motor torque output. A method of operating an electric-drive vehicle includes a controller identifying the vehicle's operating mode and determining calibration settings corresponding to this operating mode. These calibration settings include low and high coolant temperature (CoolTemp) thresholds, and motor-calibrated torque limits as a function of CoolTemp. The controller determines if the present CoolTemp of the power inverter's coolant is greater than the low CoolTemp threshold and less than the high CoolTemp threshold. If so, the controller sets a motor torque limit of the vehicle's electric motor to a torque limit value selected from a fixed torque limit region within the torque limits data between the low and high CoolTemp thresholds.

Abstract: Control of an AC motor includes rotation over an operating speed range with the output from an inverter by operating the inverter at switching frequencies that vary in proportion to rotor speed. The operating speed range is parsed into a plurality of speed regions and the switching frequencies within each operating speed region may correspond to a respective pulse ratio that is different from the respective pulse ratio corresponding to an adjacent speed region.

Abstract: A novel power inverter system for transferring electric power between a DC power source and a multi-phase electric machine is described, and includes a power inverter, a Z-source inverter, a first switch, and a second switch. The first switch is arranged between positive and negative conductors of a high-voltage bus that is electrically coupled to the DC power source, and the second switch is arranged in-line on the positive conductor of the high-voltage bus.

Abstract: Presented are high-voltage electrical systems with optimized pulse width modulation (PWM) control, methods for making/using such systems, and vehicles with enhanced electric drive capabilities via PWM type and frequency control. A method of operating an electrical system includes an electronic controller determining a PWM region layout with multiple PWM regions arranged in a torque-speed curve calibrated to an electric motor and power inverter. The controller selects one of the PWM regions based on a speed and torque of the motor, and selects a PWM type based on this selected PWM region. The controller selects a PWM switching frequency style based on the selected PWM region, and selects a PWM switching frequency based on the selected PWM region, switching frequency style, and PWM type. The controller commands a power inverter to regulate transfer of electrical power between a rechargeable battery and the motor based on the PWM type and switching frequency.

Abstract: An apparatus and a method for controlling operation of a vehicle includes a controller having a processor and a tangible, non-transitory memory. The vehicle includes a park assembly with a park actuator motor having an actuator shaft. The vehicle has a park mode and an out-of-park mode. The controller is configured to determine if the park actuator motor has reached an out-of-park position when a shift command to the out-of-park mode is received. The controller is configured to obtain and store at least one dynamic parameter associated with the park actuator motor prior to the detent member reaching the out-of-park position. The method includes determining a load factor based on the dynamic parameter over time when at least one of a predefined time threshold and a predefined motor position threshold is reached. Operation of the vehicle is controlled based at least partially on the load factor.

Abstract: A DC-DC power converter including switched inductance circuits arranged in parallel is described. Operation includes determining a commanded current and activation commands for the switched inductance circuits based upon the commanded current. This includes executing the activation commands and monitoring current in the switched inductance circuits. An average measured current is determined for each of the switched inductance circuits, and a modified activation command is determined for each of the switched inductance circuits based upon the average measured current. A time portion of the modified activation command that exceeds an end time point of a subsequent time period is determined, and the modified activation commands for the switched inductance circuits are executed, including forward-shifting that time portion of the modified activation command for each of the switched inductance circuits that exceeds the end time point.

Abstract: A DC-DC power converter including switched inductance circuits arranged in parallel is described. Operation includes determining a commanded current and activation commands for the switched inductance circuits based upon the commanded current. This includes executing the activation commands and monitoring current in the switched inductance circuits. An average measured current is determined for each of the switched inductance circuits, and a modified activation command is determined for each of the switched inductance circuits based upon the average measured current. A time portion of the modified activation command that exceeds an end time point of a subsequent time period is determined, and the modified activation commands for the switched inductance circuits are executed, including forward-shifting that time portion of the modified activation command for each of the switched inductance circuits that exceeds the end time point.

Abstract: A cascaded inverter system is described and includes an electric machine that is electrically connected in series between first and second inverters. A controller is in communication with the first and second inverters, and includes an executable instruction set. A first dead-time compensation term and a first voltage compensation term are determined based upon an initial phase current and a switching frequency for the first inverter, and a final first duty cycle is determined based thereon. Simultaneously, a second dead-time compensation term and a second voltage compensation term are determined based upon the inverted initial phase current and a switching frequency for the second inverter, and a final second duty cycle is determined based thereon. Operation of the first and second inverters are dynamically controlled based upon the final first duty cycle and the final second duty cycle, respectively.

Abstract: A DC-DC power converter is described, and includes switched inductance circuits arranged in parallel, current sensors disposed to monitor one of the switched inductance circuits, and a controller. The DC-DC power converter supplies electric power originating from a DC power source to a high-voltage bus. Control and operation includes determining a desired control mode for operating the DC-DC power converter, wherein the desired control mode includes one of a voltage control mode and a current control mode. A desired voltage and a desired differential current for operating the DC-DC power converter are determined based upon the desired control mode. A desired current for operating the DC-DC power converter is determined based upon the desired differential current. Operation of the DC-DC power converter is controlled in the desired control mode based upon the desired voltage and the desired current.

Abstract: A cascaded inverter system is described and includes an electric machine that is electrically connected in series between first and second inverters. A controller is in communication with the first and second inverters, and includes an executable instruction set. A first dead-time compensation term and a first voltage compensation term are determined based upon an initial phase current and a switching frequency for the first inverter, and a final first duty cycle is determined based thereon. Simultaneously, a second dead-time compensation term and a second voltage compensation term are determined based upon the inverted initial phase current and a switching frequency for the second inverter, and a final second duty cycle is determined based thereon. Operation of the first and second inverters are dynamically controlled based upon the final first duty cycle and the final second duty cycle, respectively.

Abstract: A torque system includes a DC power device, a polyphase electric machine, a contactor pair, a power inverter module (PIM), and a controller. The PIM connects to the power device via the contactor pair and directly connects to the electric machine. The controller executes a method to control a fault response under a fault condition resulting in opening of the contactor pair and a polyphase short condition. The controller calculates a back EMF of the electric machine and transmits switching control signals to semiconductor switches of the PIM to transition from the polyphase short condition to a polyphase open condition only when the calculated back EMF is less than a calibrated value and a voltage rise on a DC side of the PIM is less than a calibrated voltage rise. A vehicle includes the DC power device, road wheels, electric machine, PIM, and controller.