Abstract:
A method for a steer by wire steering system. The method includes determining a difference between a commanded steering ratio and an achieved steering ratio and determining whether the difference between the commanded steering ratio and the achieved steering ratio is greater than a threshold. The method also includes, in response to a determination that the difference between the commanded steering ratio and the achieved steering ratio is greater than the threshold, adjusting the commanded steering ratio to be equal to the achieved steering ratio. The method also includes, in response to a determination that the difference between the commanded steering ratio and the achieved steering ratio is greater than the threshold, selectively adjusting a bandwidth of a filter based on at least one vehicle characteristic of an associated vehicle and adjusting, using the filter, the commanded steering ratio to be equal to a desired steering ratio.
Abstract:
A method for passive damping in a steer-by-wire handwheel actuator includes selecting a number of windings for a motor of a handwheel actuator; shorting a subset of windings of the number of windings, each winding of the subset of windings being disposed at an obtuse angle from each other winding of the subset of windings; determining a resistance value for the motor; selectively adjusting the resistance value based on a number of windings associated with the subset of windings; and providing, in series with the subset of windings, at least one metal-oxide-semiconductor field-effect transistor (MOSFET) configured to: vary the resistance associated with the subset of windings based on a vehicle speed; and tune a damping characteristic associated with the handwheel actuator.
Abstract:
A method for passive damping in a steer-by-wire handwheel actuator. The method includes winding a first coil around a first tooth of a motor, winding a second coil around a first tooth of the motor, and shorting the second coil to one of an internal aspect of the motor and an external aspect of the motor.
Abstract:
A method includes receiving motor velocity data, and, in response to a determination that the motor velocity data indicates that a velocity of a motor is below a threshold velocity: calculating a thermal metric corresponding to a phase imbalance of the motor; identifying at least one thermal mitigation parameter based on the thermal metric; generating at least one thermal management motor position command based on the at least one thermal mitigation parameter; and selectively controlling the motor according to the thermal management motor position command.
Abstract:
A method of estimating a motor velocity in an electric power steering system that includes a motor is provided. The method generates motor position data by sampling an original motor position signal at an irregular sampling rate. The method estimates a motor velocity by performing a regression analysis on the motor position data.
Abstract:
A method of calculating a motor velocity in an electric power steering system comprises receiving a plurality of motor position signals from a motor position sensor of the electronic power steering system, calculating a plurality of angle difference based on the motor position signals prior to performing any filtering operations on the motor position signals, performing a linear regression analysis on the angle differences to predict an angle difference, and calculating a motor velocity based on the predicted angle difference.
Abstract:
A current reference generator to control a brushless motor in a motor control system is provided. The current reference generator includes a locate peak torque module that determines a maximum possible torque and a direct axis current that corresponds to the maximum possible torque based on motor parameters, a maximum voltage, a motor velocity of the brushless motor, and a sign of a torque command. A limit torque command module limits the torque command to the maximum possible torque. A locate minimum current module determines a value of the direct axis current that results in a minimum motor current. A solve current reference module generates a reference vector that satisfies the torque command as limited by the direct axis current that corresponds to the maximum possible torque and the direct axis current that results in the minimum motor current.
Abstract:
A method of estimating a motor velocity in an electric power steering system that includes a motor is provided. The method generates motor position data by sampling an original motor position signal at an irregular sampling rate. The method estimates a motor velocity by performing a regression analysis on the motor position data.
Abstract:
An electric machine includes a rotor structure disposed within a motor housing, wherein a second rotor end has a plurality of axially stacked laminations. The electric machine further includes a motor position sensor system which includes a first plurality of cutouts defined in the plurality of axially stacked laminations, wherein the first plurality of cutouts have a progressively smaller cross-sectional area at each lamination. The motor position sensor system also includes a second plurality of cutouts defined in the plurality of axially stacked laminations, wherein the second plurality of cutouts have a progressively smaller cross-sectional area at each lamination. The motor position sensor system further includes a plurality of motor sensors axially spaced from the second rotor end, and a plurality of sensor magnets axially spaced from the second rotor end and the plurality of motor sensors.
Abstract:
A hand wheel actuator assembly, the hand wheel actuator assembly includes a motor. The hand wheel actuator assembly also includes a motor shaft coaxially aligned with a motor axis, the motor shaft rotatably coupled to the motor, and the motor configured to cause rotation of the motor shaft about the motor axis. The hand wheel actuator assembly further includes a hand wheel shaft coaxially aligned with a hand wheel axis, the hand wheel shaft spaced from and parallel to the motor shaft, wherein the motor shaft is coupled to the hand wheel shaft by a belt. The hand wheel actuator assembly yet further includes a circuit board located between the belt and the motor.