An auxiliary power supply device includes an auxiliary power source and a booster circuit. The auxiliary power supply device is configured to be switched among a charging state, a holding state, and a discharging state. The auxiliary power source is configured to be switched between a serial connection mode and a parallel connection mode. The auxiliary power source is configured to perform boosting to supply power to the power supply target when the auxiliary power source is switched to the serial connection mode, and perform backup when the auxiliary power source is switched to the parallel connection mode.

A motor control device drives a motor based on a vehicle signal including drive assist information and performs vehicle control. The motor control device includes: a first controller and a second controller that perform a calculation operation concerning drive control over the motor. A first microcomputer corresponds to a calculation portion of the first controller. A second microcomputer corresponds to a calculation portion of the second controller. The first microcomputer and the second microcomputer mutually transmit and receive operation results by inter-microcomputer communication, or the first microcomputer unilaterally transmits an operation result from the first microcomputer by the inter-microcomputer communication. The first microcomputer and the second microcomputer synchronize timings to start and end control by performing at least one of three types of arbitration processes including: an AND-start arbitration process; an OR-start arbitration process; and a forced arbitration process.

A control device obtains a post-code extension steering torque by performing moving average processing of weighting an oversampling signal obtained by oversampling processing, obtains a base assist torque based on the post-code extension steering torque signal, acquires a base assist torque signal that decreases the base assist torque as a vehicle speed increases, performs stabilization processing on the base assist torque signal to obtain an assist torque signal according to the assist torque of an electric power steering device.

Provided is a resolver capable of increasing an accuracy of a detected angle of the resolver. The resolver includes: a stator; and a rotor, wherein the rotor includes a plurality of salient poles; wherein the stator includes: a stator core having a plurality of teeth, and a plurality of winding groups each of which is provided on each of the plurality of teeth, wherein the winding groups are divided into two systems, wherein the numbers of turns of the excitation windings are distributed in a form of a sine wave of N.sub.e-th spatial order, wherein each of the numbers of turns of a first output windings and the numbers of turns of a second output windings are distributed in a form of a sine wave of |N.sub.e±N.sub.x|-th spatial order, and wherein the following expressions are satisfied,

N.sub.out1=N.sub.1 cos{|N.sub.e±N.sub.x|(i−1)/N.sub.s×2Π+α},

N.sub.out2=N.sub.1 cos{|N.sub.e±N.sub.x|(i−1)/N.sub.s×2Π+β}, and

90(deg)<|α−β|<140(deg).

An ECU independently controls power supply to two winding systems in a motor on a per-winding-system basis based on current command values each calculated for a corresponding winding system in accordance with a target assist torque. When a first winding system fails, the ECU transitions from a first state in which the ECU causes the winding groups of the two winding systems to produce the target assist torque to a second state in which the ECU causes the winding group of the other normal winding system to produce the target assist torque. If the current command value for the normal winding system is equal to or below a current threshold value that is set with reference to zero or a value close to zero when the failed winding system recovers to its normal state in the second state, the ECU transitions from the second state to the first state.

A steer-by-wire steering system including a steering device including a steering motor and a controller configured to supply a steering current to the steering motor based on a steering request. The controller includes a plurality of microcomputers, a plurality of drive circuits, and a plurality of temperature sensors. When a detection temperature difference that is a difference between detection temperatures of any two of the plurality of temperature sensors is greater than a predetermined threshold, each of the plurality of microcomputers executes an independent calculation control to independently calculate and set a current limit value, which is an upper limit value of the steering current, based on a detection temperature of one of the plurality of temperature sensors corresponding to itself, irrespective of detection temperatures of one or more of the plurality of temperature sensors other than the one of the plurality of temperature sensors corresponding to itself.

A turning system is configured to move a turning shaft to turn a left wheel and a right wheel of a vehicle. The turning shaft is configured to couple the left wheel and the right wheel to each other. A torsion bar is engaged with the turning shaft via a steering gear box. The turning system includes: a turning mechanism including (i) an electric turning mechanism including an electric motor configured to rotate a portion of the torsion bar which is located upstream of the steering gear box and (ii) a hydraulic turning mechanism configured to apply a moving force to the turning shaft in an axial direction, the moving force being produced by a hydraulic pressure; and an electric-motor controller configured to control the electric motor based on a frictional force in the turning mechanism and a road-surface reaction force that acts between (a) a tire on the left wheel and a tire on the right wheel and (b) a road surface.

A method includes determining whether a multiphase electric machine is unstable. The method also includes, in response to a determination that the multiphase electric machine is unstable, setting a gate voltage of a first three terminal semiconductor switch to zero. The method also includes, in response to a determination that the multiphase electric machine is stable, setting the gate voltage of the first three terminal semiconductor switch to nonzero. The method also includes, in response to the first three terminal semiconductor switch being set to zero, increasing electrical conduction from one phase of the multiphase electric machine to another phase of the multiphase electric machine. The method includes, in response to the first three terminal semiconductor switch being set to nonzero, increasing electrical resistance from the one phase of the multiphase electric machine to the another phase of the multiphase electric machine.

A steering wheel locking control apparatus may include: a power supply switch configured to receive power from a battery when an ignition switch of a vehicle is turned off; and a switch unit connected to a motor, turned on when power is received through the power supply switch, and configured to lock a steering wheel through a closed circuit formed by shorting phases of the motor.

A steering control device controls a steering device that includes an electric motor. The steering control device includes a control unit configured to control an operation of the steering device by controlling the electric motor. The control unit is configured to calculate a control value for controlling the electric motor, to calculate a predetermined component indicating characteristics of the steering device using a value of a variable associated with the control value as an input, and to determine whether a mechanical abnormality has occurred in the steering device based on the calculated predetermined component.