Nidec Corporation

Nidec Elesys Corporation

Shuji Endo

Tokuji Tatewaki

Tomoya Ueda

Tomonari Mori

Masanori Watahiki

Hiroyuki Ishimura

Sohei Miyake

Masaya Ishikawa

Daisuke Notsu

Hiroaki Mizushima

Hanyu Sun

Hajime Nakane

Takuya Yokozuka

Mikio Morishima

Akitoshi Harada

Kaori Nabeshi

Hiroki Yokouchi

A control device includes a reaction force controller to generate an input torque input to a control target and control a reaction force transmitted to a steering person and an assist controller to generate a correction torque to correct the input torque based on an output of the control target and a nominal model. The assist controller includes a high-pass filter with a first cutoff frequency, a low-pass filter with a second cutoff frequency higher than the first cutoff frequency, and a disturbance compensation value calculator. When a transfer function of the low-pass filter is Q(s) and a transfer function of the high-pass filter is HPF(s), a transfer function of a control target is constrained by a transfer function of the nominal model in a frequency band in which a gain in a gain characteristic of Q(s)·HPF(s) is 1.

Control device, electric power steering device, and control method

A control device obtains an assist torque of an electric power steering device based on a steering torque, compensates for the assist torque, varies an amount of change in a compensation amount based on the steering torque, and increases the compensation amount to cancel a disturbance of the assist torque as a frequency of a disturbance affecting the steering system increases.

Control device, drive device, electric power steering device, and control method

A control device includes a reaction force controller to generate an input torque input to the control target and control a reaction force transmitted from a steering wheel to a steering person, an assist controller to generate a correction torque to correct the input torque based on an output of the control target and a nominal model, and a state feedback circuit to feed back a state compensation value to the input torque based on the output of the control target. The assist controller is configured or programmed such that the transfer function of the control target is constrained by the transfer function of the nominal model in the frequency band where the gain in the gain characteristic of the complementary sensitivity function with respect to the modeling error between the control target and the nominal model is approximately 1.

In a control device to control a motor in an electric power steering apparatus including the motor, processor executes, according to a program calculation of a target assist torque by performing proportional integral (PI) control based on a target steering wheel angle and a steering angle, and control of the motor based on the target assist torque. A gain of an integrator used for integral (I) control of the PI control is variable.

Control device and control method for electric power steering apparatus, and motor module

A motor control device includes a torque controller to operate based on a steering torque and to give an input to a control target that is a motor, and a model following controller to generate a first correction torque based on an output from the control target. A model following controller includes a high-pass filter to remove a low frequency component from a first correction torque, a friction compensation calculator that is coupled in parallel to the high-pass filter to apply friction compensation to the first correction torque to calculate an estimated value of a mechanical friction torque, and an adder to add the estimated value of the friction torque to the first correction torque from which the low frequency component is removed by the high-pass filter to generate a second correction torque and feed back the second correction torque to an input to the control target.

Motor control device, motor control method, motor module, and electric power steering device

A control device that controls a control target including at least a motor in a steering mechanism including an input shaft to which a steering wheel is connected, an output shaft connected to the input shaft via a torsion bar, and the motor connected to the output shaft. The control device includes a reaction force controller to generate an input torque input to the control target based on a torsion bar torque generated in the torsion bar and to control a reaction force transmitted from the steering wheel to the steering person, and an assist controller to generate a correction torque to correct the input torque based on an output of the control target and a nominal model. The assist controller is configured or programmed such that a transfer function of the control target is constrained by a transfer function of the nominal model in a frequency band.

A motor control device includes a model following controller to generate a correction torque based on an output from a control target that is a motor, and correct an input to the control target with the correction torque. A model following controller includes a high-pass filter with a first cutoff frequency and a low-pass filter with a second cutoff frequency larger than the first cutoff frequency, and is configured or programmed so that a transfer function of a control target is constrained to a nominal model in a frequency band in which a gain in a gain characteristic of Q(s)·HPF(s) is 1 where Q(s) is a transfer function of the low-pass filter and HPF(s) is a transfer function of the high-pass filter.

A processor acquires a steering torque detected by a steering torque sensor and a vehicle speed detected by a vehicle speed sensor, changes a gain and a phase to be applied to the steering torque in accordance with a steering frequency when a driver steers a steering wheel, determines a magnitude of an assist torque based on the steering torque to which the gain and the phase have been applied and the vehicle speed, and generates a torque command value to be used to control driving of the motor based on the determined assist torque.

Electric power steering apparatus, control device used in electric power steering apparatus, and control method

A motor control system includes an inverter and a control calculation unit. The control calculation unit includes a voltage control calculation unit that calculates a voltage command value indicating a voltage to be applied to a motor from the inverter on the basis of a current deviation between the current command value and the actual current detection value, and a compensation calculation unit that compensates at least one of a k-th component and a 1/k-th component in the motor with respect to a signal value on at least one of an upstream side and a downstream side in a signal flow that passes through the voltage control calculation unit. The compensation calculation unit calculates a compensation value on the basis of an actual angular velocity value indicating an angular velocity at which the motor rotates and the target current command value, while also taking into account advance angle control.

Motor control system and power steering system

A motor control system includes an inverter, and a control calculation unit that feedback-controls the inverter. The control calculation unit includes a voltage control calculation unit that calculates a voltage command value indicating a voltage to be applied to the motor from the inverter on the basis of a current deviation between a current command value and an actual current detection value, a torque ripple compensation calculation unit that adds a compensation value for compensating a torque ripple in the motor to a signal value on at least one of an upstream side and a downstream side in a signal flow that passes through the voltage control calculation unit, and a current limit calculation unit that limits the current command value by adaptive control based on an actual angular velocity value indicating an angular velocity at which the motor rotates.

A motor control system includes an inverter, a voltage control calculating a voltage command value indicating a voltage to be applied to a motor from the inverter based on a deviation between the current command value and the actual current detection value, and a torque ripple compensation unit adding a compensation value for compensating a torque ripple in the motor to a signal value on an upstream side in a signal flow that passes through the voltage control unit. The torque ripple compensation unit includes a phase compensator calculating a compensation value component in the voltage control unit based on an actual angular velocity value indicating an angular velocity at which the motor rotates, and an inverse characteristic processor calculating a compensation value component for compensating the torque ripple based on an inverse characteristic of an open loop transfer function in a feedback control.

A steering control device for controlling drive of a motor that drives a steering mechanism according to an operation amount of a steering wheel, includes a first torque command controller that instructs the motor on motor torque according to the operation amount of the steering wheel, and a second torque command controller that instructs the motor on the motor torque according to the operation amount of the steering wheel in parallel with the first torque command controller. The second torque command controller suppresses a frequency region corresponding to disturbance added to the steering mechanism with respect to the operation amount of the steering wheel with a filter.

Steering control device and power steering device

Both responsiveness and stability of a power assist control system are satisfied. A processor executes, in accordance with a program, determining base assist gain based on steering torque and base assist torque, generating stabilizing compensation torque based on the base assist torque, with use of a stabilizing compensator that has a second-order or higher transfer function in which a frequency characteristic is variable in accordance with the base assist gain and which is expressed using a responsiveness parameter &#x3c9; and a damping parameter &#x3b6;, and generating a current command value for use in control of the motor based on the stabilizing compensation torque.

Control device and control method for use in electric power steering device, and motor module

To improve steering feeling felt by a driver, a motor control device includes a processor and a memory which stores a program for controlling an operation of the processor. According to the program, the processor executes: switching from n-phase (n is an integer of three or more) energization control to n&#x2212;1 phase energization control in response to a switching signal; acquiring a torque command value, an electrical angle of a motor, and an actual current value of the motor; generating a pre-current command value on the basis of the torque command value, the electrical angle of the motor, and the actual current value of the motor which are acquired; generating a current command value by applying dither control to the pre-current command value in a dead point range of an electrical angle range from 0 to 2&#x3c0;; and performing the n&#x2212;1 phase energization control on the basis of the current command value.

Motor control device, control method, motor module, and electric power steering apparatus

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.

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Kyoto, Japan

Shuji Endo