Abstract: A shortening of an initial diagnosis time is achieved, even after an elapse of a predetermined delay time from an ignition switch being switched to an off-state. After the ignition switch is switched to an off-state after an operation of a control device, which drives an electric motor that applies steering assistance force to a steering system, diagnosis of a power supply circuit that supplies power to the control device is carried out, and a diagnosis item to be implemented in a succeeding initial diagnosis is determined based on a result of the diagnosis.

Abstract: A main controller includes: a d-axis current limiter configured to calculate a d-axis current limiting value with priority, based on a dq-converted current limiting value, and calculate a limited d-axis current command value by clipping the d-axis current command value to be the d-axis current limiting value or less; a q-axis current limiter configured to calculate a q-axis current limiting value, based on the dq-converted current limiting value and the limited d-axis current command value, and calculate a limited q-axis current command value by clipping the q-axis current command value to be the q-axis current limiting value or less; and an inverter controller configured to control motor current, based on the limited d-axis current command value and the limited q-axis current command value.

Abstract: A main controller includes: a d-axis current limiter configured to calculate a d-axis current limiting value with priority, based on a dq-converted current limiting value, and calculate a limited d-axis current command value by clipping the d-axis current command value to be the d-axis current limiting value or less; a q-axis current limiter configured to calculate a q-axis current limiting value, based on the dq-converted current limiting value and the limited d-axis current command value, and calculate a limited q-axis current command value by clipping the q-axis current command value to be the q-axis current limiting value or less; and an inverter controller configured to control motor current, based on the limited d-axis current command value and the limited q-axis current command value.

Abstract: A shortening of an initial diagnosis time is achieved, even after an elapse of a predetermined delay time from an ignition switch being switched to an off-state. After the ignition switch is switched to an off-state after an operation of a control device, which drives an electric motor that applies steering assistance force to a steering system, diagnosis of a power supply circuit that supplies power to the control device is carried out, and a diagnosis item to be implemented in a succeeding initial diagnosis is determined based on a result of the diagnosis.

Abstract: Provided are a motor control device (1) for controlling a motor (2) having a plurality of phases, for quickly and accurately detecting a phase in which an open-state fault has occurred when the open-state fault occurs in a target phase. When a power-supply voltage (Vb) is equal to or higher than a predetermined voltage (Vthr), a motor rotation speed (?) is equal to or lower than a predetermined speed (?thr), a target x-phase voltage command (Vx*) is not in the vicinity of zero, a current (Ix) of the target x-phase is equal to or lower than a predetermined current (Iu_thr), and a state in which a control error is equal to or larger than a predetermined error is detected over a predetermined time period or longer, occurrence of an open-state fault in the target phase is determined.

Abstract: Provided is an electric power steering control device which can realize a more appropriate countermeasure against heat in accordance with a thermal characteristic of a component used to supply a motor current. The electric power steering control device for assisting a steering force of a steering wheel of a vehicle including a control unit (10).

Abstract: Provided is an electric power steering control device which can realize a more appropriate countermeasure against heat in accordance with a thermal characteristic of a component used to supply a motor current. The electric power steering control device for assisting a steering force of a steering wheel of a vehicle including a control unit (10).

Abstract: Provided are a motor control device (1) for controlling a motor (2) having a plurality of phases, for quickly and accurately detecting a phase in which an open-state fault has occurred when the open-state fault occurs in a target phase. When a power-supply voltage (Vb) is equal to or higher than a predetermined voltage (Vthr), a motor rotation speed (?) is equal to or lower than a predetermined speed (?thr), a target x-phase voltage command (Vx*) is not in the vicinity of zero, a current (Ix) of the target x-phase is equal to or lower than a predetermined current (Iu_thr), and a state in which a control error is equal to or larger than a predetermined error is detected over a predetermined time period or longer, occurrence of an open-state fault in the target phase is determined.

Abstract: An electric power steering device that can estimate an ambient temperature and apply current limiting without using ambient temperature detecting means is provided. The electric power steering device includes a motor that supplements the driver's steering force, a controller that determines and controls the quantity of current passed to the motor, and vehicle speed detecting means. The electric power steering device includes ambient temperature estimating means provided with a vehicle speed signal input from the vehicle speed detecting means and limits the quantity of current passed to the motor according to an output from the ambient temperature estimating means.

Abstract: An electric power steering device that can estimate an ambient temperature and apply current limiting without using ambient temperature detecting means is provided. The electric power steering device includes a motor that supplements the driver's steering force, a controller that determines and controls the quantity of current passed to the motor, and vehicle speed detecting means. The electric power steering device includes ambient temperature estimating means provided with a vehicle speed signal input from the vehicle speed detecting means and limits the quantity of current passed to the motor according to an output from the ambient temperature estimating means.

Abstract: In an electric power steering apparatus in which a third motor target current is determined from a first motor target current determined on the basis of a detection torque from a steering torque detection means and a second motor target current determined using at least a detection value of the motor current detection circuit as one of inputs, and a motor drive signal is calculated on the basis of the third motor target current and a detection current from the motor current detection circuit to control a motor current, there is included a motor current detection circuit failure judgment means for judging a failure of the motor current detection circuit, and when a judgment of failure is made, at least the second motor target current is limited.

Abstract: In an electric power steering apparatus in which a third motor target current is determined from a first motor target current determined on the basis of a detection torque from a steering torque detection means and a second motor target current determined using at least a detection value of the motor current detection circuit as one of inputs, and a motor drive signal is calculated on the basis of the third motor target current and a detection current from the motor current detection circuit to control a motor current, there is included a motor current detection circuit failure judgment means for judging a failure of the motor current detection circuit, and when a judgment of failure is made, at least the second motor target current is limited.

Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.

Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.

Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.

Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.

Abstract: Conventionally, there was a problem that in cases when it is difficult to place a temperature sensor in the vicinity of a heat-generating portion, overheating could not be prevented.

Abstract: An electric power steering control system reducing steering torque without making a driver feel uncomfortable torque oscillation, including a rotation speed observer for estimating the rotation speed of a motor based on the output of a torque sensor high pass filter (HPF) and the output of a drive current HPF obtained by removing a steering frequency component from a drive current detection value.