JP2013115989A - Vehicular braking control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicular braking control device which generates braking torque by an electric motor, and can prevent needless execution of inertia compensation control for compensating influence of inertia of the entire device including inertia of the electric motor.SOLUTION: In this device, an electric motor is controlled based on a target current-carrying amount calculated based on an operation amount Bpa of a braking operation member. Based on the operation amount Bpa, whether inertia compensation control for compensating influence of inertia of a brake actuator is necessary is determined. Based on the actual position of the electric motor, whether inertia compensation control should be permitted is determined. Only when it is determined that the inertia compensation control is necessary and should be permitted, the inertia compensation control for compensating the influence of the brake actuator by adjusting the target current-carrying amount is executed.

Description

  The present invention relates to a braking control device for a vehicle.

  2. Description of the Related Art Conventionally, a vehicle braking control device that generates braking torque by an electric motor is known. In this type of apparatus, normally, an instruction current (target current) is calculated based on an operation amount of a braking operation member of a vehicle by a driver, and an electric motor is controlled based on the instruction current. Thereby, the braking torque according to operation of the braking operation member is provided to a wheel.

  In this type of device, due to the influence of the inertia of the entire device including the inertia of the electric motor (moment of inertia, mass of inertia), particularly during sudden braking (when the braking torque suddenly increases), etc. Response delay (rise delay) of braking torque at the time of acceleration (for example, when the electric motor starts up) when the rotation speed increases, and deceleration (for example, the electric motor goes to stop) when the rotation speed of the electric motor decreases. Overshoot of the braking torque can occur. Therefore, particularly during sudden braking, the influence of the inertia is compensated, that is, the braking torque response (rise performance) during acceleration of the electric motor is improved, and the braking torque overshoot when the electric motor is decelerated. Suppression (improvement of convergence) is desired.

  In order to deal with this problem, for example, Patent Document 1 describes the following. That is, based on a map that defines the relationship between the command current and the target motor rotation angle, the target motor rotation angle corresponding to the calculated command current is obtained, and the target motor rotation angle is second-order differentiated to obtain the target The motor rotation angular acceleration is determined. Based on this target motor rotation angular acceleration, an inertia compensation current for compensating for the influence of the inertia of the entire apparatus is calculated. In this case, the inertia compensation current is calculated as a positive value when the electric motor is accelerated, and is calculated as a negative value when the electric motor is decelerated. This inertia compensation current is added to the command current, and the post-compensation command current (target current) is determined. As a result, when the electric motor is started, the post-compensation command current is calculated to be larger than the command current, and the braking torque response can be improved. When the electric motor heads to stop, the post-compensation command current is calculated to be smaller than the command current, and the braking torque overshoot can be suppressed.

  In addition, the above-mentioned patent document 1 states that “when an instruction current with a high response exceeding the capacity of an electric motor is applied to the electric motor, the brake starts to be applied by inertia compensation before the actual output value rises sufficiently. The actual output value decreases, and control becomes impossible. " In order to cope with this problem, the above-mentioned Patent Document 1 describes that inertial compensation is compensation that causes the command current to drop, and if the actual output value cannot catch up with the command current, inertia The prohibition of compensation is described.

JP 2002-225690 A

  As described above, Patent Document 1 describes that when the actual output value cannot catch up with the command current, the control is prohibited during the inertia compensation control. . However, originally, whether or not the inertia compensation control should be permitted based on the actual position of the electric motor in addition to determining whether or not the inertia compensation control is necessary based on the operation amount of the braking operation member. It is desirable that the inertia compensation control is executed only when it is determined that inertia compensation is necessary and should be permitted.

  The present invention has been made to address the above-described problems, and an object of the present invention is a vehicle braking control device that generates a braking torque by an electric motor, and the influence of the inertia of the entire device including the inertia of the electric motor. It is an object of the present invention to provide an apparatus that can suppress unnecessary execution of inertia compensation control that compensates for.

  The vehicle braking control apparatus according to the present invention includes an operation amount acquisition means (BPA) for acquiring an operation amount (Bpa) of a braking operation member (BP) of a vehicle by a driver, and a braking torque for the vehicle wheel (WHL). Is generated by an electric motor (MTR) and a target energization amount (Imt) is calculated based on the operation amount (Bpa), and the electric motor (MTR) is calculated based on the target energization amount (Imt). ) And a position acquisition means (MKA) for acquiring an actual position (Mka) of the electric motor (MTR).

  The vehicle braking control apparatus according to the present invention is characterized in that the control means (CTL) requires inertia compensation control for compensating for the influence of inertia of the braking means (BRK) based on the operation amount (Bpa). It is determined whether or not the inertia compensation control should be permitted based on the actual position (Mka), it is determined that the inertia compensation control is necessary, and the inertia compensation is performed. Only when it is determined that the control should be permitted, the inertia compensation control for adjusting the target energization amount (Imt) and compensating for the influence of the inertia of the braking means (BRK) is executed. is there.

  According to this, it is determined whether or not the inertia compensation control is necessary, and it is determined whether or not the effect of the inertia compensation control can be sufficiently exhibited. The inertia compensation control is executed only when it is determined that the inertia compensation control is necessary and the effect can be sufficiently exerted to permit the inertia compensation control. As a result, unnecessary execution of the inertia compensation control is suppressed, and the control reliability can be improved.

  More specifically, whether the control means (CTL) needs the inertia compensation control at the time of acceleration in which the speed (for example, the rotation speed) of the electric motor increases based on the operation amount (Bpa). Is determined, and based on the actual position (Mka), the actual speed (dMka) of the electric motor (MTR) is calculated, and it is determined that the inertia compensation control at the time of acceleration is necessary (FLj ← 1) When the actual speed (dMka) immediately before the start is less than the first predetermined value (dm1), it is determined that the inertia compensation control during the acceleration should be permitted, and the inertia compensation control during the acceleration is necessary. The target energization amount (Imt) is increased to increase the inertia of the braking means (BRK) only when it is determined that the inertia compensation control should be permitted during acceleration (FLj ← 1). Compensate for the effects of It may be configured to perform the inertia compensation control during the acceleration.

  In order to ensure the response of braking torque during acceleration (especially during startup) of the electric motor, it compensates for the inertia of the electric motor and the static friction of the bearings, etc. It is important to improve According to the above configuration, when the electric motor is already rotating, the inertia compensation control during acceleration is prohibited, and the inertia compensation control during acceleration is executed only when the electric motor is started from a stopped state. In other words, the inertia compensation control at the time of acceleration is performed on the condition that the electric motor is stopped immediately before the calculation process for determining whether the inertia compensation control at the time of acceleration is necessary. Therefore, the response of the braking torque for starting the electric motor can be improved, unnecessary control execution can be suppressed, and the reliability of the control can be improved.

  Further, the control means (CTL) determines whether or not the inertia compensation control is necessary at the time of deceleration at which the speed (for example, the rotational speed) of the electric motor decreases based on the operation amount (Bpa). Then, based on the actual position (Mka), the actual speed (dMka) of the electric motor (MTR) is calculated and immediately before it is determined that the inertia compensation control at the time of deceleration is necessary (FLk ← 1). When the actual speed (dMka) is equal to or higher than a second predetermined value (dm2), it is determined that the inertia compensation control at the time of deceleration should be permitted, and it is determined that the inertia compensation control at the time of deceleration is necessary. However, only when it is determined that the inertia compensation control at the time of deceleration should be permitted (FLk ← 1), the target energization amount (Imt) is decreased to compensate the influence of the inertia of the braking means (BRK). To slow down It may be configured to perform the inertia compensation control.

  Similarly, inertia compensation control when the electric motor is decelerating (when the electric motor shifts from a motion state to a stop state) is necessary when the electric motor is moving at a high speed. According to the above configuration, the inertia compensation control during deceleration is prohibited when the actual speed of the electric motor is less than the predetermined value dm2, and only when the actual speed of the electric motor is equal to or greater than the predetermined value dm2 Inertia compensation control is executed. In other words, the inertia compensation control at the time of deceleration is performed on the condition that the electric motor is in a high-speed motion state immediately before the calculation process for determining whether the inertia compensation control at the time of deceleration is necessary. Accordingly, the deceleration of the electric motor immediately after the start of deceleration of the electric motor is increased, and braking torque overshoot can be efficiently suppressed, and unnecessary control execution can be suppressed, thereby improving control reliability. .

  In addition, the vehicle braking control device according to the present invention is characterized in that the control means (CTL) performs acceleration when the speed (for example, rotational speed) of the electric motor increases based on the operation amount (Bpa). When it is determined whether or not the inertia compensation control for compensating the influence of the inertia of the braking means (BRK) is necessary, and it is determined that the inertia compensation control at the time of acceleration is necessary (FLj ← 1), the target The electric motor is configured to execute an inertia compensation control at the time of acceleration for increasing an energization amount (Imt) to compensate for an influence of inertia of the braking means (BRK), and based on the operation amount (Bpa), the electric motor A state in which it is determined whether or not an inertia compensation control is required to compensate for the influence of the inertia of the braking means (BRK) at the time of deceleration at which the speed decreases, and it is determined that the inertia compensation control at the time of acceleration is necessary (F Only when it is determined that the inertia compensation control at the time of deceleration is necessary in j ← 1) (FLk ← 1), the target energization amount (Imt) is decreased to reduce the influence of the inertia of the braking means (BRK). The inertia compensation control at the time of deceleration to compensate is executed.

  In general, in a series of braking operations (operations in which the braking torque of a wheel increases from “0” and then returns to “0”), inertia compensation control is required when the electric motor is accelerated (for example, at startup). If not, the probability that inertia compensation control is required even during deceleration is low. According to the above configuration, the inertia compensation control at the time of deceleration is executed in the series of braking operations only when the inertia compensation control at the time of acceleration is required when starting the electric motor. Therefore, occurrence of a situation where inertia compensation control during deceleration is unnecessarily executed is suppressed, and control reliability can be improved.

1 is a schematic configuration diagram of a vehicle equipped with a braking control device according to an embodiment of the present invention. It is a figure for demonstrating the structure of the braking means (brake actuator) (Z section) shown in FIG. It is a functional block diagram for demonstrating the control means (brake controller) shown in FIG. It is a functional block diagram for demonstrating 1st Embodiment of the inertia compensation control block shown in FIG. It is a figure for demonstrating the maximum response of a braking means (brake actuator). FIG. 5 is a functional block diagram for explaining details of a selection calculation block shown in FIG. 4. It is a functional block diagram for demonstrating 2nd Embodiment of the inertia compensation control block shown in FIG. It is a functional block diagram for demonstrating 3rd Embodiment of the inertia compensation control block shown in FIG. It is a functional block diagram for demonstrating 4th Embodiment of the inertia compensation control block shown in FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a vehicle braking control apparatus according to the present invention will be described with reference to the drawings.

<Configuration of Entire Vehicle Equipped with Vehicle Brake Control Device According to the Present Invention>
As shown in FIG. 1, in this vehicle, a braking operation member (for example, a brake pedal) BP that is operated by a driver to decelerate the vehicle, and a braking force is generated on each wheel by adjusting the braking torque of each wheel. An electronic control unit ECU for controlling the braking means (brake actuator) BRK, BRK to be operated, and a storage battery BAT as a power source for supplying power to the BRK, ECU and the like are mounted.

  In addition, the vehicle includes a braking operation amount acquisition unit (for example, a stroke sensor and a pedal force sensor) BPA that detects an operation amount Bpa of the BP, a steering angle detection unit SAA that detects an operation angle Saa of the steering wheel SW by the driver, Yaw rate detecting means YRA for detecting the yaw rate Yra of the vehicle, longitudinal acceleration detecting means GXA for detecting the longitudinal acceleration Gxa of the vehicle, lateral acceleration detecting means GYA for detecting the lateral acceleration Gya of the vehicle, and rotational speeds of the wheels WHL (wheels Wheel speed detection means VWA for detecting (speed) Vwa is provided.

  The braking means BRK is provided with an electric motor MTR (not shown), and the braking torque of the wheel WHL is controlled by the MTR. Further, the BRK includes an energization amount detection unit (for example, an axial force sensor) FBA and an MTR energization amount (for example, current value) Ima for detecting a force Fba for the friction member to push the rotation member. For example, position detection means (for example, a rotation angle sensor) MKA for detecting the position (for example, the rotation angle) Mka of the current sensors IMA and MTR is provided.

  The detection signals (Bpa and the like) from the various detection means described above are processed by a noise removal (reduction) filter (for example, a low-pass filter) and supplied to the ECU. In the ECU, a braking control calculation process according to the present invention is executed. That is, a control means CTL described later is programmed in the ECU, and a target energization amount (for example, target current value, target duty ratio) Imt for controlling the electric motor MTR is calculated based on Bpa or the like. Further, the ECU executes arithmetic processing such as known anti-skid control (ABS), traction control (TCS), and vehicle stabilization control (ESC) based on Vwa, Yra, and the like.

<Configuration of braking means (brake actuator) BRK>
In the braking control device according to the present invention, generation and adjustment of the braking torque of the wheel WHL is performed by the electric motor MTR.

  As shown in FIG. 2, which is an enlarged view of the Z portion in FIG. 1, the braking means BRK includes a brake caliper CPR, a rotating member KTB, a friction member MSB, an electric motor MTR, a driving means DRV, a speed reducer GSK, and rotation / linear motion. The conversion mechanism KTH, the pressing force acquisition means FBA, the position detection means MKA, and the energization amount acquisition means IMA are configured.

  The brake actuator BRK is provided with a known brake caliper CPR and a friction member (for example, a brake pad) MSB, similarly to a known braking device. When the MSB is pressed against a known rotating member (for example, a brake rotor) KTB, a frictional force is generated, and a braking torque is generated on the wheel WHL.

  The drive means (drive circuit for the electric motor MTR) DRV controls the energization amount (finally the current value) to the electric motor MTR based on the target energization amount (target value) Imt. Specifically, a bridge circuit using a power transistor (for example, a MOS-FET) is configured in the driving unit DRV, the power transistor is driven based on the target energization amount Imt, and the output of the electric motor MTR is controlled. Is done.

  The output (output torque) of the electric motor MTR is transmitted to the rotation / linear motion conversion mechanism KTH via a reduction gear (for example, a gear) GSK. Then, the rotational motion is converted into a linear motion by KTH, and the friction member (brake pad) MSB is pressed against the rotational member (brake disc) KTB. The KTB is fixed to the wheel WHL, and braking torque is generated in the wheel WHL due to friction between the MSB and the KTB, and is adjusted. As the rotation / linear motion conversion mechanism KTH, a slide screw (for example, a trapezoidal screw) that performs power transmission (slip transmission) by “sliding” or a ball screw that performs power transmission (rolling transmission) by “rolling” can be used.

  The motor drive circuit DRV includes an energization amount acquisition unit (for example, a current sensor) IMA that detects an actual energization amount (for example, an electric current that actually flows through the electric motor) Ima. Further, the electric motor MTR is provided with position detecting means (for example, an angle sensor) MKA that detects a position (for example, a rotation angle) Mka. Further, a pressing force acquisition means (for example, a force sensor) FBA is provided in order to acquire (detect) a force (actual pressing force) Fba that the friction member MSB actually presses the rotating member KTB.

  In FIG. 2, a configuration of a so-called disc type braking device (disc brake) is illustrated as the braking unit BRK, but the braking unit BRK may be a drum type braking device (drum brake). In the case of a drum brake, the friction member MSB is a brake shoe, and the rotating member KTB is a brake drum. Similarly, the force (pressing force) by which the brake shoe presses the brake drum is controlled by the electric motor MTR. An electric motor MTR that generates torque by rotational motion is shown, but a linear motor that generates force by linear motion may be used.

<Overall configuration of control means CTL>
As shown in FIG. 3, the control means CTL shown in FIG. 1 includes a target pushing force calculation block FBT, an instruction energization amount calculation block IST, a pushing force feedback control block IPT, an inertia compensation control block INR, and an energization amount adjustment calculation. It is composed of block IMT. The control means CTL is programmed in the electronic control unit ECU.

  An operation amount Bpa of the braking operation member BP (for example, a brake pedal) is acquired by the braking operation amount acquisition means BPA. The operation amount (brake operation amount) Bpa of the brake operation member is based on at least one of the operation force (for example, brake pedal force) of the brake operation member by the driver and the displacement amount (for example, brake pedal stroke). Calculated. Bpa is subjected to arithmetic processing such as a low-pass filter, and noise components are removed (reduced).

  In the target pushing force calculation block FBT, the target pushing force Fbt is calculated based on the operation amount Bpa using a preset target pushing force calculation characteristic (calculation map) CHfb. The “pushing force” is the pushing force of the friction member (for example, brake pad) MSB to the rotating member (for example, brake disc) KTB in the braking means (brake actuator) BRK. The target pushing force Fbt is a target value of the pushing force.

  In the command energization amount calculation block IST, the command energization amount Ist is calculated based on the target pushing force Fbt using preset calculation maps CHs1 and CHs2. The command energization amount Ist is a target value of the energization amount to the electric motor MTR for driving the electric motor MTR of the braking means BRK and achieving the target pushing force Fbt. The calculation map (the calculation characteristic of the command energization amount) is composed of two characteristics CHs1 and CHs2 in consideration of the hysteresis of the brake actuator. The characteristic (first instruction energization amount calculation characteristic) CHs1 corresponds to the case where the pushing force is increased, and the characteristic (second instruction energization amount calculation characteristic) CHs2 corresponds to the case where the pushing force is reduced. Therefore, compared with the characteristic CHs2, the characteristic CHs1 is set to output a relatively large command energization amount Ist.

  Here, the energization amount is a state amount (variable) for controlling the output torque of the electric motor MTR. Since the electric motor MTR outputs a torque approximately proportional to the current, the current target value of the electric motor can be used as the target value of the energization amount. Further, if the supply voltage to the electric motor MTR is increased, the current is increased as a result, so that the supply voltage value can be used as the target energization amount. Furthermore, since the supply voltage value can be adjusted by the duty ratio in pulse width modulation (PWM), this duty ratio can be used as the energization amount.

  In the pressing force feedback control block IPT, the pressing force feedback energization amount Ipt is calculated based on the target pressing force (target value) Fbt and the actual pressing force (actual value) Fba. The command energization amount Ist is calculated as a value corresponding to the target pressing force Fbt, but an error (steady error) may occur between the target pressing force Fbt and the actual pressing force Fba due to fluctuations in the efficiency of the brake actuator. is there. The pushing force feedback energization amount Ipt is calculated based on a deviation (pushing force deviation) ΔFb between the target pushing force Fbt and the actual pushing force Fba, and a calculation characteristic (calculation map) CHp. ) To be reduced. Note that Fba is acquired by the pressing force acquisition means FBA.

  Inertia compensation control block INR compensates for the influence of the inertia of BRK (particularly, electric motor MTR) (inertia, inertia moment in rotational motion, or inertia mass in linear motion). In the inertia compensation control block INR, target values Ijt and Ikt of the energization amount for compensating for the influence of the BRK inertia (moment of inertia or mass of inertia) are calculated. When the electric motor is stopped or the motion (rotational motion) is accelerated from a state where the electric motor is moving at a low speed, it is necessary to improve the responsiveness of generating the pushing force. The acceleration inertia compensation energization amount Ijt corresponding to this case is calculated. Ijt is a target value of the energization amount of the acceleration control in the inertia compensation control.

  In addition, when the electric motor is decelerated and stopped from the state of motion (rotational motion), it is also necessary to suppress the overshoot of the pushing force and improve the convergence. A deceleration inertia compensation energization amount Ikt corresponding to this case is calculated. Ikt is a target value of the energization amount in the deceleration control in the inertia compensation control. Here, Ijt is a value that increases the energization amount of the electric motor (a positive value that is added to Ist), and Ikt is a value that decreases the energization amount of the electric motor (a negative value that is added to Ist). .

  In the energization amount adjustment calculation block IMT, the command energization amount Ist is adjusted by the pushing force feedback energization amount Ipt, the inertia compensation energization amount Ijt (acceleration), and Ikt (deceleration), and the target energization amount Imt is obtained. Calculated. Specifically, the feedback energization amount Ipt and the inertia compensation energization amounts Ijt and Ikt are added to the command energization amount Ist, and the sum is calculated as the target energization amount Imt. The target energization amount Imt is a final energization amount target value for controlling the output of the electric motor MTR.

<Configuration of First Embodiment of Inertia Compensation Control Block>
A first embodiment of the inertia compensation control block INR will be described with reference to FIGS. As shown in FIG. 4, in this inertia compensation control block INR, the inertia compensation control for improving the responsiveness of the pressing force due to the inertia of the MTR or the like (the inertia of the entire BRK including the inertia of the MTR) and the convergence is performed. Executed. The inertia compensation control block INR includes a control necessity determination calculation block FLG that determines whether or not inertia compensation control is necessary, an inertia compensation energization amount calculation block IJK that calculates a target energization amount of inertia compensation control, and a selection calculation block SNT (up to this point) 4) and a control availability determination calculation block FLH (see FIG. 6).

  In the control necessity determination calculation block FLG, it is determined whether the inertia compensation control needs to be executed or not. The control necessity determination calculation block FLG includes an acceleration determination calculation block FLJ that determines whether or not the electric motor is accelerated (for example, when the electric motor is started and accelerated), and when the electric motor is decelerated ( For example, it includes a deceleration determination calculation block FLK that determines whether or not it is necessary when the electric motor decelerates and stops. From the control necessity determination calculation block FLG, necessity determination flags FLj (acceleration) and FLk (deceleration) are output as determination results. In the necessity determination flags FLj and FLk, “0” represents a case where inertia compensation control is not required (unnecessary state), and “1” represents a case where inertia compensation control is necessary (necessary state).

  The control necessity determination calculation block FLG includes an operation speed calculation block DBP, an acceleration determination calculation block FLJ, and a deceleration determination calculation block FLK.

  First, in the operation speed calculation block DBP, the operation speed dBp is calculated based on the operation amount Bpa of the braking operation member BP. The operation speed dBp is calculated by differentiating Bpa.

  In the acceleration determination calculation block FLJ, the inertia compensation control when the electric motor accelerates based on the operation speed dBp (for example, when the rotation speed of the electric motor increases) is “necessary state (state where control needs to be executed). ) "And" Unnecessary state (state where control is not required to be executed) ". The determination result is output as a necessity determination flag (control flag) FLj. As the necessity determination flag FLj, “0” corresponds to “unnecessary state” and “1” corresponds to “necessary state”. Whether the inertia compensation control during acceleration is necessary is determined according to the calculation map CFLj, when the acceleration necessity determination flag FLj is “0 (unnecessary state)” when dBp exceeds a predetermined operation speed (predetermined value) db1. It is switched to “1 (necessary state)” (FLj ← 1). After that, the necessity determination flag FLj is switched from “1” to “0” (FLj ← 0) when dBp becomes less than the predetermined operation speed (predetermined value) db2. Note that FLj is set to “0” as an initial value when a braking operation is not performed.

  Furthermore, in addition to the operation speed dBp, the operation amount Bpa of the brake operation member can be used for determining whether or not the acceleration inertia compensation control is necessary. In this case, the necessity determination flag FLj switches from “0” to “1” when Bpa exceeds the predetermined operation amount (predetermined value) bp1 and dBp exceeds the predetermined operation speed (predetermined value) db1. It is done. Since the condition of Bpa> dp1 is used as a determination criterion, the influence of noise or the like in dBp is compensated, and a reliable determination can be performed.

  In the deceleration determination calculation block FLK, inertia compensation control when the electric motor decelerates based on dBp (for example, when the rotation speed of the electric motor decreases) is “necessary state (state where control needs to be executed)”. , And “unnecessary state (a state in which it is not necessary to execute control)” is determined. The determination result is output as a necessity determination flag (control flag) FLk. In the necessity determination flag FLk, “0” corresponds to “unnecessary state” and “1” corresponds to “necessary state”. Necessity determination of inertia compensation control at the time of deceleration is necessary at the time when dBp becomes less than the predetermined operation speed (predetermined value) db4 (<db3) from the state where the dBp is equal to or higher than the predetermined operation speed (predetermined value) db3 according to the calculation map CFLk. The rejection determination flag FLk is switched from “0 (unnecessary state)” to “1 (necessary state)” (FLk ← 1). Thereafter, in order to prevent the dBp from frequently repeating the acceleration control and the deceleration control, the predetermined operation speed db3 of the deceleration control can be set to a value smaller than the predetermined operation speed db1 of the acceleration control. Note that FLk is set to “0” as an initial value when a braking operation is not performed.

  Information regarding the necessity determination flags FLj and FLk for inertia compensation control is transmitted from the control necessity determination calculation block FLG to the inertia compensation energization amount calculation block IJK.

  In the inertia compensation energization amount calculation block IJK, the inertia compensation energization amount (target value) in the case where it is determined by the FLG that the inertia compensation control is necessary (when FLj = 1 or FLk = 1) is calculated. . The inertia compensation energization amount calculation block IJK includes an acceleration energization amount calculation block IJT that calculates an inertia compensation energization amount Ijt when the electric motor is accelerated (for example, when the electric motor starts and accelerates), and It includes a deceleration energization amount calculation block IKT that calculates an inertia compensation energization amount Ikt during deceleration (for example, when the electric motor decelerates and stops).

  In the acceleration energization amount calculation block IJT, the acceleration inertia compensation energization amount (first inertia compensation energization) is based on the necessity determination flag FLj and the acceleration calculation characteristic (calculation map, which is the first calculation characteristic) CHj. Amount) Ijt is calculated. The acceleration calculation characteristic CHj is stored in advance in the ECU as a characteristic (calculation map) of Ijt with respect to the elapsed time T from the time when the necessity state of acceleration inertia compensation control is determined. In the calculation characteristic CHj, Ijt is sharply increased from “0” to a predetermined energization amount (predetermined value) ij1 as time elapses from the time T is “0”, and then Ijt is predetermined energization as time elapses. The amount (predetermined value) is gradually decreased from ij1 to “0”. Specifically, CHj is a time tdn that is required for Ijt to be increased from “0” to the predetermined energization amount ij1, and that is required for Ijt to be decreased from the predetermined energization amount ij1 to “0”. Is set shorter.

  Further, as indicated by a broken line in FIG. 4, when the energization amount increases, Ijt has a “convex upward” characteristic, and is initially increased rapidly, and then CHj can be set as a characteristic that gradually increases. . Further, when the energization amount decreases, Ijt has a “convex downward” characteristic, and is initially abruptly decreased. Thereafter, CHj can be set as a characteristic that gradually decreases. The time point at which the necessity determination flag FLj is switched from “0 (unnecessary state)” to “1 (necessary state)” is defined as the origin of the elapsed time at CHj (T = 0), and the elapsed time T from the switching point. And the acceleration calculation characteristic CHj, the inertia compensation energization amount (first inertia compensation energization amount) Ijt during acceleration of the electric motor is determined. Even when the necessity determination flag FLj is switched from “1” to “0” during the calculation of Ijt, the acceleration energization amount Ijt continues to be calculated for the duration set in advance by the calculation characteristic CHj. Note that Ijt is calculated as a positive value, and adjusted so that the amount of current supplied to the electric motor MTR is increased by Ijt.

  In the deceleration energization amount calculation block IKT, a deceleration inertia compensation energization amount (second inertia compensation energization amount) based on the necessity determination flag FLk and the deceleration calculation characteristic (calculation map, second calculation characteristic) CHk. Amount) Ikt is calculated. The deceleration calculation characteristic CHk is stored in advance in the ECU as an Ikt characteristic (calculation map) with respect to the elapsed time T from the point in time when the deceleration inertia compensation control is determined. CHk is abruptly decreased from “0” to a predetermined energization amount (predetermined value) ik1 as time elapses since time T is “0”, and thereafter, Ikt is reduced to a predetermined energization amount (elapsed time). The predetermined value) is gradually increased from ik1 to “0”. Specifically, CHk is the time ten required for the time tvp required for Ikt to decrease from “0” to the predetermined energization amount ik1, and the time ten required for Ikt to increase from the predetermined energization amount ik1 to “0”. Is set shorter.

  Further, as indicated by a broken line in FIG. 4, when the energization amount decreases, Ikt has a “convex downward” characteristic, and is initially rapidly decreased, and then CHk can be set as a characteristic that gradually decreases. . Further, when the energization amount increases, Ikt has a “convex downward” characteristic, and is initially increased rapidly, and thereafter, CHk can be set as a characteristic that gradually increases. The time point at which the necessity determination flag FLk is switched from “0” to “1” is defined as the origin of the elapsed time at CHk (T = 0), and the elapsed time T from the switching time point and the deceleration calculation characteristic CHk. Based on this, an inertia compensation energization amount (second inertia compensation energization amount) Ikt at the time of deceleration of the electric motor is determined. Even if the necessity determination flag FLk is switched from “1” to “0” during the calculation of Ikt, Ikt continues to be calculated for the duration set in advance by the calculation characteristic CHk. Ikt is calculated as a negative value, and is adjusted so that the amount of current supplied to the electric motor MTR is reduced by Ikt.

  Here, the calculation characteristic CHj (first pattern) of the inertia compensation control during acceleration and the calculation characteristic CHk (second pattern) of the inertia compensation control during deceleration are based on the maximum response of the braking means (brake actuator) BRK. Determined. The output (displacement of the electric motor) appears later than the change of the input (target energization amount) to the BRK. The maximum response of BRK (the maximum state in which BRK can respond to input) is the response of MTR when a step input is given to electric motor MTR (time change in output corresponding to the time change in input) ). That is, this is a change in the actual displacement (rotation angle) Mka of the MTR when a predetermined amount of the target energization amount Imt is step-inputted (in the increasing direction from zero) to the MTR. As shown in FIG. 5, when a step input of a (predetermined) target energization amount is made to the electric motor MTR (thus, a target value Mkt of the rotation angle is a step input (of a predetermined amount mks0)), the rotation angle The actual value (output) Mka of the output changes so as to catch up with the target value (input) Mkt (following the target value with a delay). CHj and CHk are determined based on the change in Mka.

  The torque that compensates for the inertia of the entire apparatus (in particular, the inertia of the electric motor) is proportional to the rotational angular acceleration of the electric motor. In consideration of this point, in order to appropriately perform inertia compensation, the inertia compensation energization amount is calculated based on the actual acceleration (rotational angular acceleration) ddMka of the electric motor. Therefore, the actual value Mka of the displacement (rotation angle) of the MTR is second-order differentiated, the acceleration (rotation angular acceleration) ddMka is calculated, and CHj and CHk are determined based on ddMka. For example, the first and second patterns CHj and CHk can be set by multiplying ddMka by a coefficient K (constant).

  In CHj, the increase gradient (the gradient of Ijt with respect to time) when Ijt increases sharply is the increase gradient of ddMka from the start time t1 of the step input to the time t2 when the rotational angular acceleration ddMka reaches the maximum value ddm1. It is determined based on the maximum value or average value of (the slope of ddMka increasing with respect to time). Further, the decrease gradient (gradient of Ijt with respect to time) when Ijt gradually decreases is the decrease gradient of ddMka (with respect to time) from time t2 when ddMka becomes the maximum value dmm1 to time t3 when it becomes approximately zero. It is determined based on the maximum value or the average value of the decreasing ddMka slope.

  Also, based on ddMka in the maximum response (step response) (based on the change in ddMka at time points t1 to t2), when the energization amount is increased, Ijt has a “convex upward” characteristic. CHj can be set as a characteristic that is rapidly increased and then gradually increased. Similarly, based on ddMka in the maximum response (based on the change in ddMka from time t2 to t3), if the energization amount is decreased, Ijt is a “convex downward” characteristic, and is initially rapidly reduced. Thereafter, CHj can be set as a slowly decreasing characteristic.

  In CHk, the decrease slope (the slope of Ikt with respect to time) when Ikt sharply decreases is the decrease slope (time) of ddMka from time t4 when ddMka starts to decrease from time t4 to time t5 when the minimum value ddm2 is reached. Is determined based on the minimum value or the average value of the slopes of ddMka that decrease with respect to. In addition, the increase gradient (gradient of Ikt with respect to time) when Ikt increases slowly is the increase gradient of ddMka (with respect to time) from time t5 when ddMka becomes the minimum value dmm2 to time t6 when it returns to approximately zero. It is determined based on the maximum value or the average value of the increasing ddMka slope).

  Also, based on the ddMka in the maximum response (step response) (based on the change in ddMka from time t4 to t5), when the energization amount is decreased, Ikt has a “convex downward” characteristic. CHk can be set as a characteristic that is rapidly decreased and then gradually decreases. Similarly, based on the ddMka in the maximum response (based on the change in ddMka from time t5 to t6), if the energization amount is increased, Ikt is a “convex upward” characteristic, initially increasing rapidly, Thereafter, CHk can be set as a slowly increasing characteristic.

  When the electric motor MTR is accelerated (especially when the MTR is started), it is necessary to generate a torque that overcomes friction of the MTR bearing or the like, while when the MTR is decelerated (when the MTR is going to stop) The friction acts to decelerate the MTR. Therefore, the absolute value of the predetermined energization amount (first predetermined energization amount) ij1 during acceleration is set to a value larger than the absolute value of the predetermined energization amount (second predetermined energization amount) ik1 during deceleration (| ij1 |> | ik1 |).

  In the selection calculation block SNT, any one of the output of the inertia compensation energization amount Ijt when the electric motor is accelerated, the output of the inertia compensation energization amount Ikt when the electric motor is decelerated, and the control stop (output of the value “0”) One of them is selected and output. In the selection calculation block SNT, when the deceleration inertia compensation energization amount Ikt (<0) is output while the acceleration inertia compensation energization amount Ijt (> 0) is being output, Ikt is replaced with Ikt. It can be preferentially output. The inertia compensation control is performed based on time-series waveforms CHj and CHk that are set in advance using the determination of “necessary state” (necessity determination flag) as a trigger. According to the above configuration, when the driver stops the sudden braking, the inertia compensation control during acceleration (calculation of Ijt) is immediately stopped and switched to the inertia compensation control during deceleration (calculation of Ikt). Therefore, the overshoot of the pushing force can be reliably suppressed.

  In the control necessity determination calculation block FLG, whether or not the inertia compensation control is necessary is determined based on the operation speed dBp, but instead of dBp, a target pressing force speed dFb obtained by differentiating the target pressing force Fbt can be used. Further, when the position (for example, target rotation angle) Mkt of the electric motor is used as the target value, the target rotation speed dMk obtained by differentiating the target rotation angle Mkt can be used for the necessity determination. That is, the necessity of inertia compensation control can be determined based on values (speed equivalent values) dBp, dFb, and dMk corresponding to the operation speed obtained by differentiating the braking operation amount Bpa.

  Further, as shown in FIG. 6, in this embodiment, a control availability determination calculation block FLH is provided. In the control necessity determination calculation block FLG, it is determined whether or not it is necessary to execute the inertia compensation control. In the control enable / disable determination calculation block FLH, in view of the necessity of the inertia compensation control, it should be permitted. It is determined whether or not (it should be prohibited). That is, in FLH, “permitted” is determined in a state where the effect of the inertia compensation control can be sufficiently exerted, and “prohibited (control stop)” is determined in a state where the effect is assumed to be insufficient. Based on the determination result in FLH, the selection condition (Ijt, Ikt, and control stop switching) in the selection calculation block SNT can be determined. Hereinafter, FLH will be described in detail.

  At the time of acceleration based on the actual position (actual position, for example, the rotation angle of the electric motor) Mka acquired by the position acquisition means (for example, the rotation angle sensor of the electric motor) MKA in the control possibility determination calculation block FLH Whether to execute the inertia compensation control (i.e., the calculation of Ijt) of “permitted (FLm = 1)” or “prohibited (FLm = 0)” is determined.

  In the control possibility determination calculation block FLH, the speed (rotational speed) dMka of the electric motor MTR is calculated based on the actual position Mka. When the rotational speed dMka of the electric motor MTR is less than the predetermined speed (predetermined value) dm1, control execution is permitted and “1” is output as the availability determination flag FLm. On the other hand, when the rotational speed dMka of the electric motor MTR is equal to or higher than the predetermined speed (predetermined value) dm1, the control execution is prohibited and “0” is output as the availability determination flag FLm. In the selection calculation block SNT, “0 (control stop)” is selected when the availability determination flag FLm is “0”, and acceleration is performed when the availability determination flag FLm is “1”. The inertia compensation energization amount Ijt at the time is selected.

  Whether the inertia compensation control can be performed can be determined based on whether the electric motor MTR is stopped based on the actual position Mka. When the electric motor is stopped (rotational speed is zero), control execution is permitted and “1” is output as the availability determination flag FLm. On the other hand, when the electric motor is in motion (for example, performing rotational motion and generating a rotational speed), control execution is prohibited and “0” is output as the availability determination flag FLm. In the selection calculation block SNT, “0 (control stop)” is selected when the availability determination flag FLm is “0”, and acceleration is performed when the availability determination flag FLm is “1”. The inertia compensation energization amount Ijt at the time is selected.

  Immediately before the above-described acceleration inertia compensation control is determined (immediately before FLj is changed from “0” to “1”), the rotational speed of the electric motor increases in the acceleration direction (the braking torque of the wheel increases). If the direction is high (dMka ≧ dm1), or if it is already in motion (rotation) (dMka ≠ 0), it is not necessary to compensate the inertia of the electric motor or the like. Execution is prohibited. When the rotation speed of the electric motor is low in the direction to be accelerated, or in the direction opposite to the acceleration direction (direction in which the braking torque is reduced) (dMka <dm1), or stopped (the braking torque is Since the inertia compensation control at the time of acceleration is executed only in the case of (holding) (dMka = 0), highly reliable inertia compensation control can be performed.

  In the control possibility determination calculation block FLH, whether to execute the inertia compensation control at the time of deceleration (that is, calculation of Ikt) based on the actual position Mka acquired by the position acquisition means MKA is “permitted (FLn = 1)”, It is determined whether or not the control execution of “prohibit (FLn = 0)” is possible. Based on the actual position Mka, the speed (rotation speed) dMka of the electric motor is calculated. When the actual rotational speed dMka of the electric motor MTR is equal to or higher than a predetermined speed (predetermined value) dm1 (dMka ≧ dm1), control execution is permitted and “1” is output as the availability determination flag FLn. On the other hand, when the actual rotational speed dMka of the electric motor is less than the predetermined speed (predetermined value) dm1 (dMka <dm1), control execution is prohibited and “0” is output as the availability determination flag FLn. In the selection calculation block SNT, “0 (control stop)” is selected when the availability determination flag FLn is “0”, and deceleration is performed when the availability determination flag FLn is “1”. The inertia compensation energization amount Ikt at the time is selected.

  The inertia compensation control during deceleration can suppress overshoot of the electric motor MTR. However, when the electric motor is not moving fast, the necessity of inertia compensation control during deceleration is low, so inertia compensation control is prohibited when the rotation speed of the electric motor is low (when dMka <dm1). Can be done.

  Further, in the control availability determination calculation block FLH, the inertia compensation control at the time of deceleration is executed based on at least one of the energization amount (target value) Ijt for the acceleration inertia compensation control and the necessity determination flag FLj. It can be determined whether or not the control can be executed (whether Ikt calculation) is “permitted (FLo = 1)” or “prohibited (FLo = 0)”. In a series of braking operations, whether or not deceleration control is possible is determined based on whether or not the inertia compensation control during acceleration has been executed in a state before the necessary state of inertia compensation control during deceleration is determined. . When the acceleration control is not executed, it is determined as “prohibited” and “0” is output as the availability determination flag FLo. On the other hand, when the acceleration control is being executed, it is determined as “permitted”, and “1” is output as the availability determination flag FLo. In the selection calculation block SNT, when the availability determination flag FLo is set to “0 (prohibited state)”, “0 (control stop)” is selected, and the availability determination flag FLo is set to “1 (permission status)”. If so, the inertia compensation energization amount Ikt during deceleration is selected.

  When inertia compensation control is not required during acceleration of the electric motor MTR in one continuous braking operation (a series of operations until Bpa increases from the value “0” and returns to the value “0”) The probability required during deceleration is low. According to the above configuration, since the control at the time of deceleration is executed only when the “necessary state” is determined at the time of acceleration, the reliability of the inertia compensation control is improved, and the reliable control can be executed.

  Further, in the selection calculation block SNT, even when the acceleration energization amount Ijt is not reduced to “0” (that is, even when the acceleration inertia compensation control is not completed), the deceleration energization amount Ikt is output. In this case, Ijt is set to “0”, and the deceleration energization amount Ikt can be output from the selection calculation block SNT. By giving priority to Ikt over Ijt, overshooting of the electric motor MTR and surplus pressing force can be appropriately prevented when the braking operation is sudden but the operation amount is small.

<Configuration of Second Embodiment of Inertia Compensation Control Block>
Next, a second embodiment of the inertia compensation control block INR will be described with reference to FIG. As shown in FIG. 7, the inertia compensation control block INR is composed of a control necessity determination calculation block FLG, an inertia compensation energization amount calculation block IJK, and a selection calculation block SNT. Since the configurations of IJK, SNT, and FLH are the same as those of the first embodiment of the INR shown in FIGS. 4 and 6, their detailed description is omitted. Only the control necessity determination calculation block FLG will be described below.

  The control necessity determination calculation block FLG includes an operation acceleration calculation block DDBP, an acceleration determination calculation block FLJ, and a deceleration determination calculation block FLK.

  In the operation acceleration calculation block DDBP, the operation acceleration ddBp is calculated based on the operation amount Bpa of the braking operation member. The operation acceleration ddBp is calculated by second-order differentiation of Bpa. That is, the operation speed dBp is calculated by differentiating the operation amount Bpa, and further, the operation acceleration ddBp is calculated by differentiating the operation speed dBp.

  In the acceleration determination calculation block FLJ, inertia compensation control when the electric motor MTR accelerates based on the operation acceleration ddBp is “necessary state (state where control needs to be executed)” and “unnecessary state (executes control). It is determined which state is “a state that does not need to be performed”. The determination result is output as a necessity determination flag (control flag) FLj. In the necessity determination flag FLj, “0” corresponds to “unnecessary state” and “1” corresponds to “necessary state”, respectively. According to the calculation map DFLj, when the operation acceleration ddBp exceeds the first predetermined acceleration (predetermined value) ddb1 (> 0), the necessity control flag FLj for acceleration control is changed from “0 (unnecessary state)” to “1”. (Necessary state) "(FLj ← 1). Thereafter, when the operation acceleration ddBp becomes less than a predetermined acceleration (predetermined value) ddb2 (<ddb1), FLj is changed from “1” to “0” (FLj ← 0). Note that FLj is set to “0” as an initial value when a braking operation is not performed.

  In the deceleration determination calculation block FLK, the inertia compensation control when the electric motor MTR decelerates based on the operation acceleration ddBp is “necessary state (state where control needs to be executed)” and “unnecessary state (executes control). It is determined which state is “a state that does not need to be performed”. The determination result is output as a necessity determination flag (control flag) FLk. In the necessity determination flag FLk, “0” corresponds to “unnecessary state” and “1” corresponds to “necessary state”. When the operation acceleration ddBp falls below the second predetermined acceleration (predetermined value) ddb3 (<0) according to the calculation map DFLk, the necessity determination flag FLk for deceleration control is changed from “0 (unnecessary state)” to “1”. (Necessary state) "(FLk ← 1). Thereafter, when the operation acceleration ddBp becomes equal to or higher than a predetermined acceleration (predetermined value) ddb4 (> ddb3, <0), FLk is changed from “1” to “0” (FLk ← 0). Note that FLk is set to “0” as an initial value when a braking operation is not performed.

  Necessity determination flags FLj and FLk are transmitted to the inertia compensation energization amount calculation block IJK (IJT and IKT) as in the first embodiment (see FIG. 4), and a time-series preset pattern ( Calculation map) The inertia compensation energization amounts Ijt and Ikt are calculated based on CHj and CHk.

  A delay element calculation block DLY can be provided in the control necessity determination calculation block FLG. In the delay element calculation block DLY, delay element processing (first-order delay calculation) is performed on the operation amount Bpa, and ddfBp can be calculated based on the operation amount fBp after the element processing. In the delay element calculation block DLY, the response of the brake actuator BRK (particularly, the electric motor MTR) is taken into account by the transfer function. Specifically, a first-order lag calculation is performed using a time constant τm representing the response of the brake actuator BRK. Since the response of the brake actuator BRK is taken into consideration, appropriate inertia compensation control can be performed.

  In the control necessity determination calculation block FLG, it is determined whether or not the inertia compensation control is necessary based on the operation acceleration ddBp (or ddfBp subjected to the delay element processing), but instead of dddp and ddfBp, the target pressing force Fbt is determined. Alternatively, the target pushing force acceleration ddFb (the element-processed ddfFb) obtained by second-order differentiation of the element-processed fFb may be used. Further, when the position (for example, target rotation angle) Mkt of the electric motor is used as the target value, target rotation acceleration obtained by second-order differentiation of the target rotation angle Mkt (or fMk after the element processing) for necessity determination. ddMk (the element-processed ddfMk described above) can be used. That is, based on values (acceleration equivalent values) ddBp, ddFb, ddMk (or ddfBp, ddfFb, ddfMk after delay element processing) corresponding to the acceleration of the braking operation obtained by second-order differentiation of the braking operation amount Bpa. Whether or not compensation control is necessary can be determined.

  In the first embodiment of the above-described INR (see FIG. 4), both the determination operation at the time of acceleration of the electric motor (calculation of FLj) and the determination operation at the time of deceleration (calculation of FLk) are both the operation speed (corresponding to the speed). Value) based on dBp and the like, and in the second embodiment of the above-described INR (see FIG. 6), both the determination operation during acceleration (calculation of FLj) and the determination operation during deceleration (calculation of FLk) are both performed. This is performed based on operation acceleration (acceleration equivalent value) ddBp or the like. On the other hand, the control necessity determination calculation block FLG can be configured by combining “FLj calculation based on dBp and the like” and “FLk calculation based on ddBp and the like”. Alternatively, the control necessity determination calculation block FLG may be configured by combining “calculation of FLj based on ddBp or the like” and “calculation of FLk based on dBp or the like”.

<Configuration of Third Embodiment of Inertia Compensation Control Block>
Next, a third embodiment of the inertia compensation control block INR will be described with reference to FIG. Even if the acceleration inertia compensation energization amount Ijt is output as a value that takes into account the responsiveness of the electric motor MTR, the actual energization of the electric motor MTR depends on the state of the power supply voltage (for example, when there is a voltage drop). The amount does not always match the target value. For example, in the case where the actual energization amount is insufficient when the electric motor MTR is started, if the preset inertia compensation energization amount Ikt during deceleration is output, the brake actuator BRK may have insufficient pressing force. obtain. Therefore, in the present embodiment, the deceleration inertia compensation energization amount Ikt can be calculated based on the actual energization amount (for example, current value) Ima acquired by the energization amount acquisition means (for example, current sensor) IMA.

  As shown in FIG. 8, this inertia compensation control block INR is divided into a control necessity determination calculation block FLG, an inertia compensation energization amount calculation block IJK, a selection calculation block SNT, and a control enable / disable determination calculation block FLH (see FIG. 6). Configured. Since the configurations of FLG, SNT, and FLH are the same as those of the first and second embodiments of the INR shown in FIGS. 4, 6, and 7, detailed descriptions thereof are omitted. Only the inertia compensation energization amount calculation block IJK will be described below.

  The inertia compensation energization amount calculation block IJK includes an acceleration energization amount calculation block IJT and a deceleration energization amount calculation block IKT. The acceleration energization amount calculation block IJT is the same as that of the first embodiment of the INR shown in FIG.

  The deceleration energization amount calculation block IKT is provided with a data storage calculation block JDK, and time series data Jdk based on the actual energization amount Ima is stored while Ijt is being output. The actual energization amount Ima is acquired in correspondence with the inertia compensation energization amount Ijt during acceleration by the energization amount acquisition means (for example, current sensor) IMA. The time series data Jdk is stored in the data storage calculation block JDK as a characteristic of the actual energization amount Ija corresponding to Ijt with respect to time lapse T. Based on the time-series data Jdk, the deceleration-time inertia compensation energization amount Ikt is calculated.

  In the deceleration energization amount calculation block IKT, first, the command energization amount Ist and the feedback energization amount Ipt are subtracted (subtracted) from the actual energization amount Ima, and the inertia compensation energization amount during acceleration (target value). An actual energization amount (actual value) Ija corresponding to Ijt is calculated. That is, the energization amount Ija corresponding to Ijt is calculated by removing the component due to Ist and the component due to Ipt from Ima. Then, the corresponding energization amount Ija is multiplied by “−1” (the sign is inverted), and further multiplied by the coefficient k_ij to calculate the energization amount Ikb stored in the data storage operation block JDK.

  In the data storage calculation block JDK, the storage energization amount Ikb has elapsed since the time when the acceleration control necessity determination flag FLj transited from “0 (unnecessary state)” to “1 (necessary state)” (T = 0). It is stored as time-series data Jdk in association with time (that is, elapsed time from the start of inertia compensation control during acceleration) T. The time series data Jdk based on the actual energization amount Ima is used as a characteristic (calculation map) for calculating Ikt. Inertia at the time of deceleration based on the elapsed time T from the time (T = 0) when the necessity judgment flag FLk for deceleration control transitions from “0 (unnecessary state)” to “1 (necessary state)” and Jdk The compensation energization amount Ikt is calculated.

  When accelerating (especially when starting), it is necessary to generate torque that overcomes the friction of the bearings of the electric motor MTR, but when decelerating (when stopping), the friction acts to decelerate the MTR. Due to that, the coefficient k_ij may be set to a value less than “1”.

  In the above description, the storage energization amount Ikb is calculated for each calculation cycle, but the values of Ima, Ist, and Ipt corresponding to the elapsed time T are stored as time series data, and the characteristic Jdk is calculated using these values. Can be computed. That is, characteristics (calculation map) based on the calculation of time series data Jdk = (− 1) × (k_ij) × {(Ima time series data) − (Ist time series data) − (Ipt time series data)}. ) Jdk may be determined.

  According to the third embodiment of the INR, the inertia compensation control at the time of deceleration is executed based on the actual energization amount Ima when the inertia compensation control at the time of acceleration is performed. Even if an error occurs between the actual value and the actual value, appropriate inertia compensation control can be executed.

<Configuration of Fourth Embodiment of Inertia Compensation Control Block>
Next, a fourth embodiment of the inertia compensation control block INR will be described with reference to FIG. In preparation for this, various symbols are defined below. “F” attached to various symbols is a state quantity (such as fMk) obtained by performing a delay element calculation process having a time constant τm, which will be described later, on the original state quantity (such as Mkt). It is called “process value”. The “original state quantity (original value)” is a value before the calculation process of the delay element, and is referred to as “unprocessed value”. Further, “d” attached to various symbols is a value obtained by first-order differentiation of the original state quantity (such as fMk), and is a state quantity (such as dfMk) corresponding to the speed. This state quantity (a value obtained by first-order differentiation of the “original state quantity”) is referred to as “speed value” or “speed equivalent value”. A state quantity (such as dfMk) obtained by first-order differentiation of the processing value (such as fMk) is referred to as “processing speed value (post-processing speed value)” or “processing speed equivalent value (post-processing speed equivalent value)”. The Furthermore, “dd” given to various symbols is a value obtained by second-order differentiation of the original state quantity (such as fMk), and is a state quantity (such as ddfMk) corresponding to acceleration. This state quantity (a value obtained by second-order differentiation of the “original state quantity”) is referred to as “acceleration value” or “acceleration equivalent value”. The state quantity (ddfMk and the like) obtained by second-order differentiation of the processing value (fMk and the like) is referred to as “processing acceleration value (post-processing acceleration value)” or “processing acceleration equivalent value (post-processing acceleration equivalent value)”. The

  As shown in FIG. 9, in the fourth embodiment of the inertia compensation control block INR, the responsiveness and convergence of the pressing force due to the inertia of the MTR and the like (the inertia of the entire BRK including the inertia of the MTR) are improved. Inertia compensation control is executed. The inertia compensation control block INR includes a target position calculation block MKT, a time constant calculation block TAU, a delay element calculation block DLY, a target acceleration calculation block DDM, and a gain setting block KMTR. Further, the fourth embodiment of the INR is the same as the “selection operation block SNT” (see FIG. 4 etc.) and the same as the first to third embodiments of the INR shown in FIG. 4, FIG. 6, FIG. A “control availability determination calculation block FLH” (see FIG. 6) is provided.

  In the target position calculation block MKT, a target position (target rotation angle) Mkt is calculated based on the target pressing force Fbt and the target pressing force calculation characteristic (calculation map) CHmk. The target position Mkt is a target value for the position (rotation angle) of the electric motor MTR. The calculation map CHmk is a characteristic corresponding to the rigidity of the brake caliper CPR and the friction member (brake pad) MSB, and is stored in advance in the electronic control unit ECU as a non-linear characteristic of “upwardly convex”.

  In the time constant calculation block TAU, the time constant τm is calculated based on the braking operation amount Bpa and the time constant calculation characteristic (calculation map) CHτm. When the operation amount Bpa is less than the predetermined operation amount (predetermined value) bp1, τm is calculated as a first predetermined time constant (predetermined value) τ1 (≧ 0). When Bpa is equal to or greater than the predetermined value bp1 and less than the predetermined value bp2, τm is calculated so as to sequentially increase from the first predetermined time constant τ1 to the second predetermined time constant τ2 as Bpa increases. When Bpa is equal to or greater than the predetermined value bp2, τm is calculated as a second predetermined time constant (predetermined value) τ2 (> τ1).

  Alternatively, the time constant τm can be calculated based on the calculation characteristic (calculation map) CHτn. In the calculation map CHτn, when Bpa is less than the predetermined value bp1, τm is calculated to the predetermined value τ1 (≧ 0), and when Bpa is equal to or greater than the predetermined value bp1, τm is set to the predetermined value τ2 (> τ1). Can be computed. In the calculation characteristics CHτm and CHτn, when the braking operation amount Bpa is small, the predetermined value τ1 can be set to “0” so that the delay element calculation process is not performed.

  In the delay element calculation block DLY, the target position (process value) fMk after the delay element calculation process is calculated based on the target position Mkt of the electric motor MTR. Specifically, a delay element calculation process including a time constant τm corresponding to the response of the brake actuator BRK (that is, the response of the electric motor MTR) is executed for the target position (original value) Mkt of the electric motor. Then, the element-processed target position (process value) fMk is calculated. Here, the delay element calculation is an operation of an nth order delay element (“n” is an integer equal to or greater than “1”), for example, a first order delay calculation. When the delay element process is performed at Mkt, the response of the brake actuator BRK (the state of the output change with respect to the input change) is considered as a transfer function using a time constant, and the target value fMk corresponding to the response is obtained. Can be computed.

  In the target acceleration calculation block DDM, the target acceleration (process acceleration value) ddfMk after the delay element processing is calculated based on the target position (process value) fMk after the delay element processing. ddfMk is a target value of acceleration (angular acceleration) of the electric motor MTR. Specifically, fMk is second-order differentiated and ddfMk is calculated. The ddfMk is calculated as a positive sign value when the electric motor MTR is accelerated (when starting from the stopped state), and is calculated as a negative sign value when the MTR is decelerating (when moving toward the stop).

  The gain setting block KMTR stores a coefficient (gain) k_mtr for converting the target acceleration (process acceleration value) ddfMk after the delay element processing into the target energization amount of the electric motor. The coefficient k_mtr corresponds to a value obtained by dividing the inertia (constant) j_mtr of the electric motor by the torque constant k_tq of the electric motor. Then, inertia compensation control energization amounts (target values) Ijt and Ikt are calculated based on ddfMk and k_mtr. Specifically, Ijt and Ikt are calculated by multiplying ddfMk by k_mtr.

  In the fourth embodiment of the INR (see FIG. 9), a target position (unprocessed value) Mkt is calculated based on the target pushing force Fbt, and a delay element calculation process (first-order lag calculation) is performed on Mkt. The target position (process value) fMk after the delay element processing is calculated, fMk is second-order differentiated to calculate the target acceleration (process acceleration value) ddfMk, and Ijt and Ikt are calculated based on ddfMk. Instead of these calculation processes, the target pressing force (unprocessed value) Fbt is subjected to the delay element processing, and the target pressing force (processing value, processing target pressing force) fFb after the delay element processing is calculated, and fFb Is subjected to second order differentiation to calculate the target pushing force acceleration (process acceleration value) ddfFb, and the inertia compensation energization amounts Ijt and Ikt can be calculated based on ddfFb. Further, a delay element process is performed on Bpa, an operation amount (process value) fBp after the delay element process is calculated, fBp is second-order differentiated, an operation acceleration (process acceleration value) ddfBp is calculated, and based on ddfBp Thus, the inertia compensation energization amounts Ijt and Ikt can be calculated. That is, in the inertia compensation control block INR, the delay element calculation is performed on the unprocessed values (Bpa, Fbt, Mkt) calculated based on the operation amount Bpa of the braking operation member BP, and the processed value (the value after the delay element calculation). ) FBp, fFb, fMk can be computed. Then, the processing values fBp, fFb, and fMk are second-order differentiated to calculate processing acceleration values (values corresponding to accelerations obtained by second-order differentiation of the processing values) ddfBp, ddfFb, ddfMk, and processing acceleration values ddfBp, ddfFb, ddfMk. Based on the above, the inertia compensation energization amounts Ijt and Ikt can be calculated.

  The torque that compensates for the inertia of the electric motor is proportional to the rotational angular acceleration. For this reason, in order to appropriately perform inertia compensation, it is necessary to appropriately calculate the rotational angular acceleration (or a value corresponding thereto) of the electric motor. In view of this point, in the fourth embodiment of the INR, the responsiveness of the electric motor MTR is considered as a transfer function using a time constant. Specifically, a time constant τm (a target value of the target value) corresponding to the responsiveness of the electric motor MTR with respect to a state quantity that is one of the raw values Bpa, Fbt, and Mkt calculated based on Bpa. The processing values fBp, fFb, and fMk are calculated by applying a delay element (for example, a first-order delay element) calculation having a time until it reaches approximately 63.2%. Then, based on the processing values fBp, fFb, and fMk, the processing acceleration values (values corresponding to the second-order differentiated accelerations) ddfBp, ddfFb, and ddfMk are calculated, so that the target values Ijt and Ikt of the inertia compensation control are appropriate. Can be computed.

  Hereinafter, operations and effects common to the embodiments of the inertia compensation control block INR will be described. In the inertia compensation control, the energization amount (Ijt, Ikt) corresponding to the force (torque) necessary for the movable part (MTR, etc.) of the device having inertia to perform the acceleration motion or the deceleration motion is set as the target energization amount Imt. It is control which adjusts with respect to. Specifically, when the electric motor accelerates, compensation (correction) is performed by increasing the target energization amount, and when the electric motor decelerates, compensation (correction) is performed by decreasing the target energization amount. According to each of the above embodiments, inertia compensation control is executed only when it is determined that inertia compensation is necessary and should be permitted (particularly, see FIG. 6). As a result, unnecessary execution of the inertia compensation control is suppressed, and the control reliability can be improved.

  In addition, in order to ensure the response of the braking torque when the electric motor MTR is accelerated (particularly during startup), the electric motor starts to move by compensating for the inertia of the electric motor and the static friction of the bearings ( It is important to improve the movement from the stop state. According to each of the above embodiments, when the electric motor has already moved (rotated) in the direction in which the braking torque of the wheel is increased, the inertia compensation control during acceleration is prohibited (FLm ← 0), and the electric motor The inertia compensation control at the time of acceleration is executed only when the engine is started from the stop state. In other words, the electric motor is in a low-speed motion state (dMka <dm1) or the electric motor is in a stopped state (dMka = 0) immediately before the inertia compensation control necessity determination calculation process during acceleration. ), Inertia compensation control during acceleration is performed. Therefore, the response of the braking torque for starting the electric motor can be improved, unnecessary control execution can be suppressed, and the reliability of the control can be improved.

  Similarly, inertia compensation control when the electric motor MTR is decelerating (when the electric motor shifts from a motion state to a stop state) is necessary when the electric motor is moving (rotating) at a high speed. According to the above configuration, when the speed of the electric motor is low (already stopped), inertia compensation control during deceleration is prohibited (FLn ← 0), and only when the electric motor is moving at high speed. Inertia compensation control during deceleration is executed. In other words, the inertia compensation control at the time of deceleration is performed on the condition that the electric motor is in a high-speed motion state (dMka ≧ dm2) immediately before the calculation processing for determining whether the inertia compensation control at the time of deceleration is necessary. Accordingly, the deceleration of the electric motor immediately after the start of deceleration of the electric motor is increased, and braking torque overshoot can be efficiently suppressed, and unnecessary control execution can be suppressed, thereby improving control reliability. .

  In general, in a single continuous braking operation, when inertia compensation control is not required at the start of the electric motor, the probability that inertia compensation control is required also during subsequent deceleration is low. According to the above embodiments, the inertia compensation control at the time of deceleration is executed only when the inertia compensation control at the time of acceleration is required at the time of starting the electric motor (FLo ← 1). That is, when inertia compensation control is not executed when the electric motor is started, inertia compensation control is prohibited during deceleration. Therefore, occurrence of a situation where inertia compensation control during deceleration is unnecessarily executed is suppressed, and control reliability can be improved.

  In the above embodiment, whether or not the inertia compensation control is necessary is determined by the FLG, and when it is determined that the inertia compensation control is necessary, the inertia compensation energization amounts Ijt and Ikt are calculated, and in parallel with this calculation, Only when the inertia compensation control is determined by FLH and the inertia compensation control is permitted, Ijt and Ikt are finally output from the selection calculation block SNT, but the inertia compensation control is necessary, and Only when permitted, Ijt and Ikt can be calculated in the inertia compensation energization amount calculation block IJK. In this case, SNT is omitted, and the determination result (FLj, FLk) of the control necessity determination calculation block FLG and the determination result (FLm, FLn, FLo) of the control necessity determination calculation block FLH are the inertia compensation energization amount. Ijt and Ikt can be calculated only when the inertia compensation control is necessary and permitted, transmitted to the calculation block IJK.

  BRK ... brake actuator, ECU ... electronic control unit, MTR ... electric motor, BPA ... braking operation amount detection means, SAA ... steering angle detection means, YRA ... yaw rate detection means, GXA ... longitudinal acceleration detection means, GYA ... lateral acceleration detection means , VWA ... wheel speed detection means, FBA ... push force detection means, IMA ... energization amount detection means, position detection means ... MKA

Claims (4)

An operation amount acquisition means for acquiring an operation amount of the braking operation member of the vehicle by the driver;
Braking means for generating braking torque for the wheels of the vehicle by an electric motor;
A control means for calculating a target energization amount based on the operation amount, and controlling the electric motor based on the target energization amount;
A vehicle braking control apparatus comprising:
A position acquisition means for acquiring an actual position of the electric motor;
The control means includes
Based on the operation amount, it is determined whether or not inertia compensation control for compensating for the influence of inertia of the braking means is necessary,
Based on the actual position, it is determined whether to allow the inertia compensation control,
The inertia compensation that adjusts the target energization amount to compensate for the influence of the inertia of the braking means only when it is determined that the inertia compensation control is necessary and it is determined that the inertia compensation control should be permitted A braking control device for a vehicle configured to execute control. The vehicle braking control device according to claim 1,
The control means includes
Based on the manipulated variable, determine whether or not the inertia compensation control at the time of acceleration at which the speed of the electric motor increases,
Calculate the actual speed of the electric motor based on the actual position;
Determining that the inertia compensation control during acceleration should be permitted when the actual speed immediately before determining that the inertia compensation control during acceleration is less than a first predetermined value;
Determining that inertial compensation control during acceleration is necessary, and
Only when it is determined that the inertia compensation control at the time of acceleration should be permitted, the inertia compensation control at the time of acceleration that increases the target energization amount to compensate for the influence of the inertia of the braking means is executed. In addition, a vehicle braking control device. In the vehicle brake control device according to claim 1 or 2,
The control means includes
Based on the manipulated variable, determine whether the inertia compensation control is required at the time of deceleration at which the speed of the electric motor decreases,
Calculate the actual speed of the electric motor based on the actual position;
When the actual speed immediately before determining that the inertia compensation control at the time of deceleration is more than a second predetermined value, it is determined that the inertia compensation control at the time of deceleration should be permitted,
Only when it is determined that the inertia compensation control at the time of deceleration is necessary, and it is determined that the inertia compensation control at the time of deceleration should be permitted, the target energization amount is decreased to influence the inertia of the braking means A braking control device for a vehicle configured to execute inertia compensation control at the time of deceleration to compensate for. An operation amount acquisition means for acquiring an operation amount of the braking operation member of the vehicle by the driver;
Braking means for generating braking torque for the wheels of the vehicle by an electric motor;
A control means for calculating a target energization amount based on the operation amount, and controlling the electric motor based on the target energization amount;
In a vehicle braking control apparatus comprising:
The control means includes
Based on the manipulated variable, it is determined whether or not an inertia compensation control for compensating for the influence of the inertia of the braking means at the time of acceleration at which the rotational speed of the electric motor increases, and the inertia compensation control at the time of acceleration is performed. Is configured to execute the inertia compensation control at the time of acceleration to increase the target energization amount and compensate for the influence of the inertia of the braking means,
Based on the operation amount, it is determined whether or not an inertia compensation control for compensating for the influence of the inertia of the braking means at the time of deceleration at which the rotation speed of the electric motor decreases,
Only when it is determined that the inertia compensation control at the time of acceleration is necessary and the inertia compensation control at the time of deceleration is determined to be necessary, the target energization amount is reduced to reduce the influence of the inertia of the braking means. A vehicle braking control device configured to execute inertia compensation control at the time of deceleration to compensate.

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