Abstract: A motor control system for determining a ripple compensating current is provided. The motor control system includes a motor having a plurality of motor harmonics and a motor frequency, and a bandwidth compensation controller that is in communication with the motor. The bandwidth compensation controller is configured to determine a magnitude response compensation value and a phase compensation value for each of the plurality of motor harmonics. The magnitude response compensation value and the phase compensation value are both based on the motor frequency. The bandwidth compensation controller is configured to determine the ripple compensating current based on the magnitude response compensation value and the phase compensation value.

Abstract: A motor control system is provided. The motor control system includes a motor having plurality of motor harmonics, and a torque ripple compensation controller in communication with the motor. The torque ripple compensation controller is configured to determine a harmonic ripple current for a corresponding one of the plurality of motor harmonics. The harmonic ripple current is based on a reference q-axis current and a reference d-axis current. The torque ripple compensation controller is configured to add the harmonic ripple current for each of the plurality of motor harmonics together to determine the ripple compensating current.

Abstract: A learning function is configured to determine a plurality of piecewise linear function coefficients based on measured data for an electric power-assisted steering (EPS) system. The measured data include a vehicle speed. The learning function is further configured to model a hysteresis loop of the EPS system using a piecewise linear function based on the plurality of piecewise linear function coefficients to determine an average friction. An average friction change compensator is configured to adjust friction-based EPS system compensation based on the average friction for a plurality of vehicle speed intervals of the vehicle speed.

Abstract: A motor control system is provided. The motor control system includes a motor having plurality of motor harmonics, and a torque ripple compensation controller in communication with the motor. The torque ripple compensation controller is configured to determine a harmonic ripple current for a corresponding one of the plurality of motor harmonics. The harmonic ripple current is based on a reference q-axis current and a reference d-axis current. The torque ripple compensation controller is configured to add the harmonic ripple current for each of the plurality of motor harmonics together to determine the ripple compensating current.

Abstract: A method for controlling operation of a torque-assist motor includes determining a rotational position of the torque-assist motor and producing a motor speed signal that is indicative of a rotational speed of the motor. One or more gain factors are produced based on the rotational speed of the torque-assist motor. An electrical current applied to the torque-assist motor is detected, and a current error is calculated based on a commanded electrical current and the electrical current applied to the torque-assist motor. A quadrature axis voltage is calculated based on the current error and the one or more gain factors. An inverter is driven with a direct voltage signal that is phased with the rotational position of the torque-assist motor so as to produce the electrical current applied to the torque-assist motor. The electrical current exhibits a characteristic that is affected by the quadrature axis voltage.

Abstract: A motor control system for determining a ripple compensating current is provided. The motor control system includes a motor having a plurality of motor harmonics and a motor frequency, and a bandwidth compensation controller that is in communication with the motor. The bandwidth compensation controller is configured to determine a magnitude response compensation value and a phase compensation value for each of the plurality of motor harmonics. The magnitude response compensation value and the phase compensation value are both based on the motor frequency. The bandwidth compensation controller is configured to determine the ripple compensating current based on the magnitude response compensation value and the phase compensation value.

Abstract: A motor control system is provided. The motor control system includes a motor having plurality of motor harmonics, and a torque ripple compensation controller in communication with the motor. The torque ripple compensation controller is configured to determine a harmonic ripple current for a corresponding one of the plurality of motor harmonics. The harmonic ripple current is based on a reference q-axis current and a reference d-axis current. The torque ripple compensation controller is configured to add the harmonic ripple current for each of the plurality of motor harmonics together to determine the ripple compensating current.

Abstract: A learning function is configured to determine a plurality of piecewise linear function coefficients based on measured data for an electric power-assisted steering (EPS) system. The measured data include a vehicle speed. The learning function is further configured to model a hysteresis loop of the EPS system using a piecewise linear function based on the plurality of piecewise linear function coefficients to determine an average friction. An average friction change compensator is configured to adjust friction-based EPS system compensation based on the average friction for a plurality of vehicle speed intervals of the vehicle speed.

Abstract: A method for controlling operation of a torque-assist motor includes determining a rotational position of the torque-assist motor and producing a motor speed signal that is indicative of a rotational speed of the motor. One or more gain factors are produced based on the rotational speed of the torque-assist motor. An electrical current applied to the torque-assist motor is detected, and a current error is calculated based on a commanded electrical current and the electrical current applied to the torque-assist motor. A quadrature axis voltage is calculated based on the current error and the one or more gain factors. An inverter is driven with a direct voltage signal that is phased with the rotational position of the torque-assist motor so as to produce the electrical current applied to the torque-assist motor. The electrical current exhibits a characteristic that is affected by the quadrature axis voltage.