Abstract: A apparatus may be configured to select a number of windings for a motor of a handwheel actuator; short a subset of windings of the number of windings; determine a resistance value for the motor; and selectively adjust, based on a number of windings associated with the subset of windings and to tune a damping characteristic associated with the handwheel actuator, the resistance value by varying at least one of (i) a number of winding turns associates with the subset of windings, (ii) a wire diameter of associated with the subset of windings, (iii) a number of wires associated with the subset of windings and (iv) a material associated with the subset of windings.

Abstract: Technical solutions are described for providing driver warning using steering systems. An example steering system includes a motor control system that sends a command to a motor. The steering system further includes a fault monitoring system that sets a fault indication flag by monitoring one or more components of the steering system. The steering system further includes a driver warning feedback system that generates a warning injection signal based on and in response to the fault indication flag being set. Further, the motor control system generates a driver feedback by modifying the command to the motor using the warning injection signal, and sending the modified command to the motor.

Abstract: Technical solutions are described for providing driver warning using steering systems. An example steering system includes a motor control system that sends a command to a motor. The steering system further includes a fault monitoring system that sets a fault indication flag by monitoring one or more components of the steering system. The steering system further includes a driver warning feedback system that generates a warning injection signal based on and in response to the fault indication flag being set. Further, the motor control system generates a driver feedback by modifying the command to the motor using the warning injection signal, and sending the modified command to the motor.

Abstract: According to one or more embodiments of the present invention a steer by wire steering system includes a deviation detection unit configured to determine a deviation signal that is indicative of a disturbance in one or more components coupled to a rack. The steer by wire steering system further includes a handwheel notification module configured to generate a modification signal based on the deviation signal, in response to the deviation signal being detected for at least a predetermined duration. The steer by wire steering system further includes a handwheel control module that generates an input command corresponding to a reference torque generated by a road wheel actuator, a feedback torque for a driver is generated based on the input command. The handwheel control module further modifies the input command using the modification signal, the modification providing a notification corresponding to the disturbance to the driver.

Abstract: According to one or more embodiments of the present invention a steer by wire steering system includes a deviation detection unit configured to determine a deviation signal that is indicative of a disturbance in one or more components coupled to a rack. The steer by wire steering system further includes a handwheel notification module configured to generate a modification signal based on the deviation signal, in response to the deviation signal being detected for at least a predetermined duration. The steer by wire steering system further includes a handwheel control module that generates an input command corresponding to a reference torque generated by a road wheel actuator, a feedback torque for a driver is generated based on the input command. The handwheel control module further modifies the input command using the modification signal, the modification providing a notification corresponding to the disturbance to the driver.

Abstract: Technical solutions are described for providing driver warning using steering systems. An example steering system includes a motor control system that sends a command to a motor. The steering system further includes a fault monitoring system that sets a fault indication flag by monitoring one or more components of the steering system. The steering system further includes a driver warning feedback system that generates a warning injection signal based on and in response to the fault indication flag being set. Further, the motor control system generates a driver feedback by modifying the command to the motor using the warning injection signal, and sending the modified command to the motor.

Abstract: Technical solutions are described for providing driver warning using steering systems. An example steering system includes a motor control system that sends a command to a motor. The steering system further includes a fault monitoring system that sets a fault indication flag by monitoring one or more components of the steering system. The steering system further includes a driver warning feedback system that generates a warning injection signal based on and in response to the fault indication flag being set. Further, the motor control system generates a driver feedback by modifying the command to the motor using the warning injection signal, and sending the modified command to the motor.

Abstract: Technical solutions are described for detecting an error in an inverter associated with a motor of a power steering system and operating the power steering system in response to the error. An example system includes a transistor pair that selectively provides power to a corresponding phase coil of the motor. The system further includes a detection module that detects a resistance error in the transistor pair by monitoring a voltage across a shunt resistor of the transistor pair in response to a gate drive command applied to the transistor pair. The system further includes a mitigation module that selects a mode of operation of the inverter based on the resistance error. The system also includes a motor control module that controls the inverter according to the mode of operation.

Abstract: Technical solutions are described for mitigating braking torque in a motor of a steering system caused by a FET short. For example, an example mitigation system includes a mitigation module that adjusts a motor torque in response to a FET short. The mitigation system further includes a mitigation-enable module that selectively enables and disables the mitigation module based on a handwheel torque signal. Further, the mitigation system includes a damping module that reduces the motor torque based on a motor velocity signal for the motor.

Abstract: Technical solutions are described for detecting an error in an inverter associated with a motor of a power steering system and operating the power steering system in response to the error. An example system includes a transistor pair that selectively provides power to a corresponding phase coil of the motor. The system further includes a detection module that detects a resistance error in the transistor pair by monitoring a voltage across a shunt resistor of the transistor pair in response to a gate drive command applied to the transistor pair. The system further includes a mitigation module that selects a mode of operation of the inverter based on the resistance error. The system also includes a motor control module that controls the inverter according to the mode of operation.

Abstract: A power steering system includes a torque modifier module that generates a modified torque command in response to a current sensor fault, a magnitude of the modified torque command changes over a time period. The power steering system also includes a feedforward selection module that applies a dynamic feedforward compensation to a motor current command, thereby generating a motor voltage that is applied to a motor of the power steering system, the dynamic feedforward compensation modifies a frequency response of the power steering system.

Abstract: A method of controlling a motor of a power steering system is provided. The method generates a direct-axis voltage command and a quadrature-axis voltage command based on a current measurement signal received from the motor. The method transforms the direct-axis voltage command and the quadrature-axis voltage command into an alpha voltage command and a beta voltage command. The method determines an offset error in the phase current measurement based on the alpha and beta voltage commands.

Abstract: An embodiment of a system for determining a sensor failure in a motor control system with at least three phase current measurements includes a magnitude computation module that determines a magnitude of a diagnostic voltage, the diagnostic voltage represented in a stator frame and based on a difference between an input voltage command and a final voltage command, and a phase evaluation module that determines a phase value of the diagnostic voltage based on the diagnostic voltage. The system also includes a sensor failure identification module that identifies a current sensor failure based on the phase value of the diagnostic voltage, the sensor failure represented by a failure signal, and a current calculation transition module that modifies a calculation scheme for determining a measurement of motor current based on the sensor failure.

Abstract: Technical solutions are described for mitigating braking torque in a motor of a steering system caused by a FET short. For example, an example mitigation system includes a mitigation module that adjusts a motor torque in response to a FET short. The mitigation system further includes a mitigation-enable module that selectively enables and disables the mitigation module based on a handwheel torque signal. Further, the mitigation system includes a damping module that reduces the motor torque based on a motor velocity signal for the motor.

Abstract: A power steering system includes a torque modifier module that generates a modified torque command in response to a current sensor fault, a magnitude of the modified torque command changes over a time period. The power steering system also includes a feedforward selection module that applies a dynamic feedforward compensation to a motor current command, thereby generating a motor voltage that is applied to a motor of the power steering system, the dynamic feedforward compensation modifies a frequency response of the power steering system.

Abstract: A method of controlling a motor of a power steering system is provided. The method generates a direct-axis voltage command and a quadrature-axis voltage command based on a current measurement signal received from the motor. The method transforms the direct-axis voltage command and the quadrature-axis voltage command into an alpha voltage command and a beta voltage command. The method determines an offset error in the phase current measurement based on the alpha and beta voltage commands.

Abstract: A method and system for determining a torque current in an electric machine coupled to a polyphase bus. The method comprises: detecting a rotational position of the electric machine with a position encoder; controlling an inverter comprising a plurality of switching devices, the inverter having an input coupled to a direct current bus, and an output coupled to the polyphase bus. Where the inverter is responsive to commands from a controller coupled to the inverter and to the position encoder. The method also includes measuring a current from the direct current bus; and capturing the current at a predefined interval of time.

Abstract: A method for implementing active deadtime control of an inverter associated with an electric motor is disclosed. In an exemplary embodiment, the method includes receiving a command voltage signal indicative of a desired load to be driven by the motor. Based upon the value of the command voltage signal, a determined value of deadtime is applied to switching circuitry in the inverter, wherein the value of deadtime relates to an amount of time in which the switching of a device in the switching circuitry is delayed so as to prevent a short circuit condition within the inverter.

Abstract: A method for implementing active deadtime control of an inverter associated with an electric motor is disclosed. In an exemplary embodiment, the method includes receiving a command voltage signal indicative of a desired load to be driven by the motor. Based upon the value of the command voltage signal, a determined value of deadtime is applied to switching circuitry in the inverter, wherein the value of deadtime relates to an amount of time in which the switching of a device in the switching circuitry is delayed so as to prevent a short circuit condition within the inverter.

Abstract: Disclosed is a system for dead time switching in a sinusoidally excited PM electric machine. The system comprises: a PM electric machine; a position sensor configured to measure a position of the electric machine and transmit a position signal; and a controller, where the controller receives the position signal. The controller executes a method comprising: obtaining a duty cycle command; generating a first control command signal to an upper switching device and a second control command signal to a lower switching device configured to drive the electric machine in response to the duty cycle command; and applying a dead time to the first control command signal to ensure that the upper switching device and the lower switching device are not conducting simultaneously; and wherein the dead time comprises a turn on delay and an advance turn off.