The present disclosure relates to a technology for removing adverse effects on input torque by torque offset to improve and maintain a control function related to steering. A method for controlling torque offset compensation in a steering system, includes obtaining a torque offset value (input torque change value) for each steering angle under a hands-off condition of a steering wheel; determining compensation torque configured to counterbalance the torque offset value regarding the steering angle when the steering wheel is steered; and determining a final torque by applying the compensation torque to an input torque detected according to steering of the steering wheel.

A control device for a motor including a first coil and a second coil which are insulated from each other is provided. The control device includes a first circuit and a second circuit that switches a first process to a second process when the first circuit fails. The external circuit generates an instruction for performing a process of increasing an amount of operation which is calculated by one of the first circuit and the second circuit according to the number of control systems when the other of the first circuit and the second circuit fails.

An electric power steering system includes a vehicle speed sensor configured to detect a vehicle speed, a motor driving circuit configured to supply power to an electric motor, a main power supply and a capacitor that can supply power to a driving circuit, a charging circuit configured to charge the capacitor based on the main power supply, and an ECU for power source control that controls the charging circuit. The ECU for power source control drives the charging circuit to charge the capacitor only when the vehicle speed is lower than a first predetermined value and an inter-terminal voltage of the capacitor is lower than a second predetermined value.

In an electric power steering system, an offset correction value setting unit corrects second offset correction values in a state where 100% of current command values is distributed to a first control unit, and 0% of the current command values is distributed to a second control unit. The offset correction value setting unit corrects first offset correction values in a state where 100% of the current command values is distributed to the second control unit, and 0% of the current command values is distributed to the first control unit.

The present invention relates to a drive control apparatus for an electric motor and a control method thereof. In the present invention, the generation of electric brake is suppressed while protecting a semiconductor relay from excessive surge voltage. The drive control apparatus is configured to include: a drive circuit for controlling the drive of the electric motor; a semiconductor relay arranged on a drive line between the drive circuit and the electric motor to cut off current supply from the drive circuit to the electric motor; and an active clamp circuit for turning on the semiconductor relay when a potential difference between the drive circuit side and the electric motor side of the semiconductor relay is greater than or equal to a predetermined value.

An electric power steering apparatus arranged in the vicinity of a heat source mounted on a vehicle includes: a rack shaft that turns a road wheel; an output shaft provided with a pinion gear engaged with a rack gear of the rack shaft; a worm wheel provided on the output shaft; a worm shaft engaged with the worm wheel; an electric motor that drives the worm shaft; and a controller that controls driving of the electric motor, and wherein at least a part of the controller is arranged on the opposite side of the heat source such that a rack housing is sandwiched between at least a part of the controller and the heat source, the rack housing accommodating the rack shaft.

An electric power steering apparatus that performs an assist control of a steering system, including: at least two respectively independent torque sensors and angle sensors, wherein having a function that respectively calculates steering angles from the torque sensors and the angle sensors to utilize, wherein comparison diagnoses of independent signals are performed and also concurrently individual diagnoses of each individual signal are performed, in a case that it is judged that there is an abnormality in the comparison diagnoses, the angle sensor signals are not used, in a case that it is judged that at least one of the individual diagnoses is abnormal, the angle sensor signal is treated as downgrading, and in a case that it is judged that two or more of the individual diagnoses are abnormal, the angle sensor signals are not used.

A connector structure that is joined to a housing so as to form the control unit includes a connector main body in which a connector is formed, a terminal including a power supply system and a signal system, and a component mounting portion including at least one of a capacitor and a coil, wherein the component mounting portion is provided parallel to a motor output shaft on the exterior of a motor or the housing, and the at least one of the capacitor and the coil included in the component mounting portion is electrically connected directly to the connector of the connector main body via the terminal.

A motor drive circuit comprises a motor having a plurality of phases, a switching circuit comprising a plurality of electrical switches, a motor current controller that generates voltage demand signals to be passed to a drive circuit for the switches that in turn generate pulse width modulated switching signals for the switching circuit that cause the switches to selectively connect the phases to a power supply so as to cause current to flow through the phases of the motor, and a motor torque controller that produces a demand signal that is fed to an input of the current controller, the motor current controller responding to an error signal that is at least partially dependent on the value of the demand signal. The torque controller in use updates the demand signal at a first sample rate. The motor drive circuit further comprises a downsampling circuit that in use modifies the demand signal under certain operating conditions so that the demand signal is only updated at a second sample rate that is lower than the first rate.

A steering angle detecting apparatus for vehicles includes a vernier calculating section that performs vernier calculation based on a steering shaft angle and a motor angle, a neutral period specifying section that specifies a neutral period including a neutral point based on a reference angle calculated by the vernier calculation in the vernier calculating section, and a neutral point specifying section that specifies the neutral point from the neutral period and a stored neutral point value, and outputs a steering angle the neutral point of which is specified.