Gm Global Technolgoy Operations, Inc.

Jihoon Jang

Bon Ho Bae

Silva Hiti

Yo Chan Son

Steven E Schulz

Wei D Wang

Harry J Bauer

Dwarakanath V Simili

Jeong J Park

Brian A Welchko

William R Cawthorne

Nitinkumar R Patel

Sean W McGrogan

Sinisa Jurkovic

Daniel L Kowalewski

Krunal P Patel

Leah Dunbar

Milan Ashok Vadera

Jung Sik Yim

Terry Murrell

An electric machine assembly has an electric machine having a stator and a rotor. The rotor has a rotor temperature and is configured to rotate at a rotor speed (&#x3c9;). The stator has stator windings at a stator winding temperature (t) and the electric machine defines a number of pole pairs (P). A controller is operatively connected to the electric machine and is configured to receive a torque command (T*). The controller has a processor and tangible, non-transitory memory on which is recorded instructions for executing a method for determining a total permanent magnetic flux (&#x3c8;) as a function of the rotor temperature. Execution of the instructions by the processor causes the controller to determine a high-speed magnetic flux factor (&#x3c8;) and a low-speed magnetic flux factor (&#x3c8;).

Determination of permanent magnetic flux in an electric machine

An electric machine assembly includes an electric machine having a stator and a rotor. The stator has stator windings at a stator winding temperature (t) and the rotor is configured to rotate at a rotor speed (&#x3c9;). A controller is operatively connected to the electric machine and has a processor and tangible, non-transitory memory on which is recorded instructions for executing a method for determining stator winding resistance. The controller is configured to determine a high-speed resistance factor (r) which is based at least partially on the torque command (T*), the stator winding temperature (t), the rotor speed (&#x3c9;), a characterized torque error and the number of pole pairs (P). The controller may determine a total resistance value (R) based on a weighting factor (k), the high-speed resistance factor (r) and the low-speed resistance factor (r).

Determination of stator winding resistance in an electric machine

A method for controlling an electrically-powered torque machine of a powertrain system includes determining a predicted torque command to control the torque machine. A flux command is determined responsive to the predicted torque command. The flux command is a flux level providing a fast torque reserve that is responsive to the predicted torque command. The fast torque reserve is a prescribed minimum rate of change in torque output from the torque machine responsive to the predicted torque command. An inverter controller controls flux of the torque machine responsive to the flux command.

Method and apparatus for controlling an electrically-powered torque machine of a powertrain system

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.

Method and apparatus for controlling an electric machine in a six-step mode

A powertrain system includes a torque machine rotatably coupled to an internal combustion engine via a pulley mechanism. The torque machine and the internal combustion engine are configured to transfer torque to a driveline and include a first sensor configured to monitor rotation of the engine and a second sensor configured to monitor rotation of the torque machine. The first sensor signally connects to a controller configured to control operation of the torque machine. A method for operating the powertrain system includes employing a signal output from the first sensor to monitor rotation of the torque machine to control operation thereof, said signal output from the first sensor adjusted for a pulley ratio of the pulley mechanism upon detecting a fault associated with the second sensor.

Method and apparatus for fault mitigation in a torque machine of a powertrain system

Embodiments of the present disclosure relate to methods, systems and apparatus for adjusting current and/or torque commands used to control operation of an asynchronous machine based on rotor flux of the asynchronous machine.

Methods, systems and apparatus for adjusting current and/or torque commands used to control operation of an asynchronous machine

A method for monitoring an electric motor employing a pulse-type rotational position sensor includes monitoring a signal output from the pulse-type rotational position sensor and a reference signal associated with a control signal for the electric motor. A position of a rotor of the electric motor coincident with the reference signal is determined based upon a nominal rotor position, a nominal rotational speed of the rotor and a time between the reference signal and a falling edge of the signal output from the pulse-type rotational position sensor. The electric motor is controlled based upon the position of the rotor.

Method and apparatus for monitoring rotational position of an electric machine

Methodologies and systems are provided for current estimation in electric motor. The system comprises an electric motor having sensors for sensing at least motor current, motor temperature and motor speed. A vehicle controller is coupled to the sensors and includes a closed-loop current control system for the electric motor having a current compensation circuit for providing a current compensation signal that is used to adjust a current command for the electric motor. The current compensation circuit includes a short-circuit current calculator for providing a short-circuit current value based upon the motor temperature and the motor speed, a compensation gain calculator for providing a gain compensation value based upon the motor speed, and circuitry for combining the motor current, the short-circuit current value and the gain compensation value to provide the current compensation signal. Methods for current estimation in electric motor are also provided.

System and method for current estimation for operation of electric motors

Embodiments of the present disclosure relate to methods, systems and apparatus for estimating angular position and/or angular velocity of a rotor of an electric machine.

Methods, systems and apparatus for estimating angular position and/or angular velocity of a rotor of an electric machine

Methods and systems are provided for motor torque control for hybrid vehicles having a motor and a communications bus. The motor torque is controlled using a first motor torque capacity if the communications bus is healthy. The motor torque is controlled using a second motor torque capacity if the communications bus is unhealthy. The first motor torque capacity has a first absolute value. The second motor torque capacity has a second absolute value that is less than the first absolute value.

Method and system for controlling motor torque in hybrid vehicles

Methods and systems for controlling motor torque in a hybrid vehicle are provided. A current sensor provides a feedback current when the sensor is operating properly. A processor controls the motor torque using the feedback current if the current sensor is operating properly. The processor controls the motor torque using a slip value for the hybrid vehicle if the current sensor is not operating properly.

Method and system for motor torque control for vehicles when a current sensor is not operating properly

Methods and systems for controlling an electric motor are provided. The motor includes a plurality of windings. Each winding is coupled to a respective set of first and second switches. The first switch of each set of switches is simultaneously activated. Current flow through the plurality of windings is measured while the first switch of each set of switches is activated. The electric motor is controlled according to a first motor control method if the measured current is below a predetermined threshold. The electric motor is controlled according to a second motor control method if the measured current is above the predetermined threshold.

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Torrance, CA, United States of America

Jihoon Jang