Abstract: [Problem] An object of the present invention is to provide a high-performance electric power steering apparatus that can smoothly switch a steering control mode with a simple structure and does not make a driver uncomfortable when the driver steers a handle in an automatic steering control.

Abstract: [Problem] An object of the present invention is to provide a high-performance electric power steering apparatus that can smoothly switch a steering control mode with a simple structure and does not make a driver uncomfortable when the driver steers a handle in an automatic steering control.

Abstract: An electric power steering apparatus that drives a motor based a current command value and assist-controls a steering system by a driving-control of the motor. The apparatus includes a handle-returning control section that calculates a target steering angular velocity by using a steering angle, the vehicle speed, the steering torque and the current command value, calculates a handle-returning control current by using a limit-target steering angular velocity which is obtained by limiting the target steering angular velocity depending on steering angular velocity, and drives the motor by a compensated current command value which is obtained by adding the handle-returning control current to the current command value.

Abstract: A control unit for an electric power steering apparatus that constitutes a model following control that an output of a controlled object follows-up to an output of a reference model, eliminates or reduces the occurrences of a noisy sound and a shock force at an end hitting without giving any uncomfortable steering feeling, takes a safety countermeasure against the model following control and suppresses the variation of the control output in a case that the safety countermeasure is excessively operated.

Abstract: An electric power steering apparatus that drives a motor based a current command value and assist-controls a steering system by a driving-control of the motor. The apparatus includes a handle-returning control section that calculates a target steering angular velocity by using a steering angle, the vehicle speed, the steering torque and the current command value, calculates a handle-returning control current by using a limit-target steering angular velocity which is obtained by limiting the target steering angular velocity depending on steering angular velocity, and drives the motor by a compensated current command value which is obtained by adding the handle-returning control current to the current command value.

Abstract: An electric power steering apparatus that includes a function to perform a handle-returning control being consistent with an intention of a driver by using, for a calculation of a target steering angular velocity, only a steering input due to the intention of the driver which is included in a steering torque and the assist current or only vehicle motion characteristics based on the steering input, in the handle-returning control which performs a PID-control depending on a deviation between the target steering angular velocity and a steering angular velocity.

Abstract: An electric power steering apparatus that includes a function to perform a handle-returning control being consistent with an intention of a driver by using, for a calculation of a target steering angular velocity, only a steering input due to the intention of the driver which is included in a steering torque and the assist current or only vehicle motion characteristics based on the steering input, in the handle-returning control which performs a PID-control depending on a deviation between the target steering angular velocity and a steering angular velocity.

Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus that gradual-changes a steering angle control command value, an assist control command value and also a steering angle speed command value, suppresses an excessive accumulation of an integral value in a speed control by being provided a steering speed command value with a limiter, and does not give the driver an uncomfortable feeling.

Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus that gradual-changes a steering angle control command value, an assist control command value and also a steering angle speed command value, suppresses an excessive accumulation of an integral value in a speed control by being provided a steering speed command value with a limiter, and does not give the driver an uncomfortable feeling.

Abstract: To provide an electric power steering apparatus capable of suppressing a vibration of an assist torque while keeping a steering feeling. A current command value is calculated by adding a torque differential compensation value depending on a differential value of a steering torque to a basic assist current command value calculated based on the steering torque and vehicle speed. In this situation, the torque differential compensation value is calculated to be smaller when the steering speed of a steering wheel falls within a specific steering speed region in which a resonance phenomenon easily occurs due to a disturbance vibration of a steering assist torque, in comparison with when the steering speed falls outside the specific steering speed region.

Abstract: An electric power steering apparatus including a steering wheel return control section that calculates a steering wheel return control current by a steering angle, the steering torque, the vehicle speed and a steering angle velocity, and drives the motor by a compensation current command value made by adding the steering wheel return control current to the current command value.

Abstract: An electric power steering apparatus including a steering wheel returning control section for driving a motor by a compensation current command value. The apparatus calculates a target returning torque based on a steering angle and a vehicle speed, corrects the target returning torque with a steering torque and an assist torque, multiplies by a transmission characteristic corresponding to a virtual steering system characteristic based on a correction torque and a viscosity coefficient, multiplies a deviation between a target steering angle speed and an actual steering angle speed by a vehicle speed gain and a steering torque gain to obtain a steering wheel returning control gain, and performs control calculation with respect to the steering wheel returning control gain, performs an output limit in response to the vehicle speed gain and the steering torque gain, and obtain a steering wheel returning control current.

Abstract: An active-return control section that calculates a return control current based on a steering angle, the vehicle speed and a motor angular velocity/Gr ratio, and drives the motor by a compensated-current command value obtained by subtracting the return control current from the current command value. The active-return control section includes a base-return control current calculating section that calculates a base-return control current, a target steering velocity calculating section that calculates a target steering velocity, a return control gain calculating section that obtains a deviation between the target steering velocity and the motor angular velocity/Gr ratio and sign-processes, and calculates a return control gain by at least two among a P-control calculation, an I-control calculation and a D-control calculation, a limiter that limits a maximum value of the return control gain, and a correcting section to output the return control current by correcting the control current with output of the limiter.

Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus that is capable of positively returning a steering wheel to a neutral point in such a running state as to return to a going straight state by calculating a return control current corresponding to a steering angle and a steering speed and compensating a current command value.

Abstract: An electric power steering apparatus including a steering wheel return control section that calculates a steering wheel return control current by a steering angle, the steering torque, the vehicle speed and a steering angle velocity, and drives the motor by a compensation current command value made by adding the steering wheel return control current to the current command value.

Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus that is capable of realizing a smooth steering wheel returning control by the correction based on a steering torque in which vehicle characteristics are considered and a vehicle speed even in the case of steering intervention by a driver in a straight-advancing running state.

Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus that is possible to actively return the steering wheel to the neutral point at the vehicle running state to give back to a straight running state by calculating the return control current corresponding to the steering angle and the motor angular velocity/Gr ratio and by compensating the current command value.

Abstract: Although the steering angle control of a steering wheel is performed using automatic steering control, when the steering torque is applied by the steering wheel operation of the driver, the target steering angle is corrected to become the same direction as a direction that the steering torque is applied, and the steering angle control is performed to coincide with that target steering angle. Thereby, in the case of adding together outputs of the steering angle control with respect to the corrected target steering angle and the assist control by the steering torque with a certain ratio, it is possible to make the output direction of the automatic steering control coincide with the output direction of the manual steering control, and the control outputs become hard to interfere with each other. As a result, the uncomfortable feeling given to the driver that occurs in switching the steering mode is reduced.

Abstract: An electric power steering apparatus that detects that a driver has steered the handle by using a steering torque detected by a torque sensor, switches to the manual steering mode due to a capacity (an integrated value) corresponding to a generated torque, and does not provide an uncomfortable feeling to the driver.

Abstract: [Problem] An object of the present invention is to provide an electric power steering apparatus that is capable of positively returning a steering wheel to a neutral point in such a running state as to return to a going straight state by calculating a return control current corresponding to a steering angle and a steering speed and compensating a current command value.