An electric power steering apparatus includes a function to switch a control system of the motor between a torque control system of a torque system to control a motor output torque and a position and speed control system of a steering angle system to control a steering angle of a steering in accordance with an ON/OFF of a post-diagnosis automatic steering command being a judgment result of an automatic steering execution judging section; and a characteristic calculating section to calculate a fade gain signal F1 that applies a first fade characteristic of the torque system, a fade gain signal F2 that applies a second fade characteristic of the steering angle system, and a fade gain signal F3 that applies a third fade characteristic of the steering angle speed, sensitive to the steering torque.

A motor control system includes plural control circuits and plural motor circuits. Each motor circuit includes an inverter circuit and a coil. The plural motor circuits are controlled by any one of the control circuits or controlled by the plural control circuits in combination. When any one of the control circuits controlling the motor circuits fails, the motor control system performs switching control so that the failing control circuit is disconnected while another normally-operating control circuit controls the corresponding motor circuit. The failure detection and switching control are performed smoothly and quickly to recover the motor control system from the failure, thus enhancing the reliability.

When detecting an abnormality in a portion related to control of an electric motor, a CPU that calculates a control amount for controlling the electric motor calculates a control amount different from a control amount at a normal time so as to continue the control of the electric motor and changes a threshold value for detecting the abnormality to a value different from a value at a normal time.

Two systems of individually-provided arithmetic units in a control device of a multi-phase rotating machine perform control calculation for a control of electric current flowing from power converters to the multi-phase windings. The arithmetic units of the respective systems communicate information via inter-system communication at least in one direction, and perform current control calculation of the electric current flowing in the multi-phase windings of a subject system in a cycle shorter than a communication cycle of the inter-system communication, and calculate a decoupling control amount of the electric current flowing in the multi-phase windings of the subject system, for a decoupling control of a voltage generated in the multi-phase windings of the subject system by the electric current flowing in the multi-phase windings of an other system by using an estimated current that is calculated based on a current instruction value of the subject system or of the other system.

A steering apparatus for vehicles that easily obtains equivalent steering torques to vehicle driving information such as a steering angle without being affected by a road surface state and aging-changes of mechanism characteristics of a steering system. The steering apparatus includes a torsional angle control section that calculates a motor current command value based on a target torsional angle corresponding to vehicle driving information and the torsional angle, and includes a torsional angle feedback compensating section that calculates a target torsional angular velocity by a deviation between the target torsional angle and the torsional angle. A torsional angular velocity calculating section calculates a torsional angular velocity by the torsional angle, and a velocity control section calculates a pre-limitation motor current command value by performing proportional compensation based on the target torsional angular velocity and the torsional angular velocity. An output limiting section limits upper and lower limit values of the pre-limitation motor current command value, and outputs the motor current command value which is used to control the motor.

Method for monitoring the operation of a power steering system including a steering wheel, a servo motor and a monitoring module, characterized in that said method involves a step of determining at least one temporary limit value of a parameter, a step of estimating an additional value which an assistance functionality contributes to a setpoint value of the parameter, and a step of correcting the at least one temporary limit value by the additional value.

A steer-by-wire steering system for motor vehicles may include a primary steering level with a steering transmission device, which is arranged to subject wheels of the motor vehicle to a desired setpoint steering effect, and a secondary steering level with a safety device that provides predefined functions, so that in the case of a malfunction of the primary steering level, steering the wheels remains possible during an emergency mode. The steer-by-wire steering system may also include an authentication system with a communications interface for communications with the safety device. The authentication system may be arranged so that in the case of a successful authorization, the secondary steering level of the steer-by-wire steering system is also available after the emergency mode.

A motor driving apparatus includes a first driving control circuit (an MCU, a driving circuit, an input circuit, a power management IC) and a second driving control circuit (an MCU, a driving circuit, an input circuit, a power management IC). The first driving control circuit and the second driving control circuit are configured to drive a corresponding winding group of winding groups of a motor, and have a master mode for outputting a synchronous trigger signal in synchronization with driving of the corresponding winding group and a slave mode for synchronizing the driving of the corresponding winding group with an input synchronous trigger signal. When an error has occurred in an operation of the first driving control circuit in the master mode, the second driving control circuit switches an operation mode of the second driving control circuit from the slave mode to the master mode.

A computer includes a processor and a memory storing instructions executable by the processor to determine a learned clear vision offset based on a currently calculated clear vision offset and a previously stored clear vision offset, and steer a steer-by-wire system of a vehicle while correcting a steering angle by a lesser value of the learned clear vision offset and a maximum correctable offset.

A control system for a motor includes: a first processing circuit configured to operate a first drive circuit; a second processing circuit configured to operate a second drive circuit; and a command circuit configured to output a signal relating to a command value for a steered angle of a steered wheel to the first processing circuit and the second processing circuit. The command circuit is configured to execute a detection process, a first notification process, and a second notification process. The first processing circuit is configured to execute a first correction process based on a first result signal to control the steered angle to the command value. The second processing circuit is configured to execute a second correction process based on a second result signal to control the steered angle to the command value.