JP5970953B2 - Brake control device for vehicle and brake control method for vehicle - Google Patents

Description

  The present invention relates to a vehicle brake control device and a vehicle brake control method.

  The prior art of Patent Document 1 includes an electric brake made of an electric caliper and a regenerative brake made of a generator. When an abnormality occurs in the electric brake, the electric brake in which the abnormality has occurred is disconnected from the power line. Yes. As a result, the electric brake that operates normally and the regenerative brake are protected, and a braking force according to the driver's braking request can be secured.

JP 2004-243846 A

By the way, there is a situation where the operation of the regenerative brake is limited. For example, when the battery is fully charged, the generator is overheated, or the battery is cold, it is necessary to limit the operation of the regenerative brake to protect the battery and generator. . Therefore, in a configuration with multiple brake systems including a regenerative brake, there is a possibility that the operation of the regenerative brake may be restricted even in a situation where an abnormality occurs in a system other than the regenerative brake and a backup by the regenerative brake is necessary. There is.
The subject of this invention is improving the reliability of the backup function by a regenerative brake when abnormality generate | occur | produces in some brake systems among several friction brake systems.

A vehicle brake control device according to an aspect of the present invention includes a friction brake including a plurality of brake systems, a battery capable of charging / discharging electric power, and driving the vehicle during powering operation using electric power from the battery, and during electric power generation operation. And an electric motor that charges the battery by regeneration. The electric motor is allowed to be regenerated by the power generation operation when the state of the charging system satisfies a predetermined charging permission condition. Then, an abnormality in a part of the brake system in the friction brake is detected, and when the remaining brake system is in a normal and operable state, the state of the charging system is controlled so as to satisfy the charging permission condition. The charge allowable condition is that the charge amount of the battery is below a predetermined charge amount allowable upper limit value. Then, a charge amount margin threshold value smaller than the charge amount allowable upper limit value is set in advance, and when the battery charge amount is charged to the charge amount margin threshold value, charging of the battery from the electric motor is limited. Moreover, when the abnormality of all the brake systems in a friction brake is detected, the restriction | limiting of the charge with respect to the battery from an electric motor is cancelled | released.

  According to the present invention, when an abnormality in a part of the brake system in the friction brake is detected, the state of the charging system is controlled so as to satisfy the charging permission condition, so that regeneration due to the power generation operation of the motor is allowed. That is, since the backup performance by the regenerative brake can be ensured, the reliability of the backup performance can be improved.

It is a schematic block diagram of a powertrain and a brake system. 2 is a schematic configuration diagram of an electric booster 24. FIG. 3 is a schematic configuration diagram of a brake actuator 25. FIG. It is a flowchart which shows a brake control process. It is a map used for calculation of required torque Td.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<< First Embodiment >>
"Constitution"
This embodiment optimally controls the friction brake and the regenerative brake as the regenerative cooperative brake control, and is a vehicle brake control device that is employed in an electric vehicle (EV) or a hybrid vehicle (HEV). Here, an electric vehicle will be described as an example.
FIG. 1 is a schematic configuration diagram of a powertrain and a brake system.
The power train includes a lithium ion battery 11, an inverter 12, and a motor 13. During the power running operation of the motor 13, the electric power from the lithium ion battery 11 is supplied to the motor 13 via the inverter 12. The driving force of the motor 13 is transmitted to the wheel 15 via the speed reducer 14.

  The brake system includes a friction brake including a plurality of brake systems, and a regenerative brake. The friction brake includes a brake pedal 21, a master cylinder 22, a wheel cylinder 23, an electric booster 24, and a brake actuator 25. The regenerative brake is a regenerative brake by the power generation operation of the motor 13, converts the rotational energy transmitted from the wheel 15 into electric energy and charges the lithium ion battery 11, and uses the rotational resistance during the power generation operation as a regenerative braking force. The lithium ion battery 11 can also be charged from an external power source.

  In the present embodiment, a battery controller 31, a brake controller 32, an EV controller 33, and an actuator controller 34 are provided. Each controller is connected by two independent systems such as CSMA / CA multiplex communication (CAN: Controller Area Network) as monitoring communication between controllers, and exchanges various data. Each controller obtains power from a 12V battery 35, and the 12V battery 35 is charged by the power of the lithium ion battery 11 via the DC / DC converter 36. The DC / DC converter 36 is provided for two systems, and is provided separately from an electric double layer capacitor (DLC: Double Layer Capacitor). The stroke sensor 26 for detecting the brake operation amount of the brake pedal 21 has three signal lines and is individually input to the brake controller 32, the EV controller 33, and the actuator controller 34.

The battery controller 31 in the lithium ion battery 11 grasps a state of charge (SOC), an output possible value, and an input possible value. In addition, it performs voltage deviation optimization of each cell, prevention of overvoltage and overcurrent, prevention of overheating, detection of a decrease in insulation resistance of a high voltage circuit, detection of fitting of a high voltage harness connector and a service plug, and the like.
The brake controller 32 calculates a target braking force according to the operation amount of the brake pedal 21 detected by the stroke sensor 26 and transmits the target braking force to the EV controller 32. In addition, the target regenerative torque transmitted from the EV controller 32 is received, the target hydraulic pressure is calculated according to the value obtained by subtracting the target regenerative torque from the target braking force, and the electric booster 24 is driven and controlled. Assists brake operation (boost action). Moreover, the abnormality diagnosis of the electric booster 24 is performed by the abnormality diagnosis system.

The EV controller 33 selectively executes either motor output control that is a power running operation of the motor 13 or motor regeneration control that is a power generation operation of the motor 13.
In the motor output control, the target driving force is calculated from the accelerator opening, the vehicle speed, the shift position, etc., and the target driving force torque is calculated by performing the limiting process on the target driving force based on the driving force limit request from each system. The power running operation of the motor 13 is controlled.

In the motor regeneration control, a target regeneration torque is calculated according to the target braking force received from the brake controller 32, a regeneration restriction process is performed on the target regeneration torque based on the regeneration restriction request from each system, and transmitted to the brake controller 32. At the same time, the power generation operation of the motor 13 is controlled.
In this embodiment, for convenience, a positive value of the motor torque is described as a power running torque, and a negative value of the motor torque is described as a regenerative torque.

  The actuator controller 34 performs anti-skid control (ABS), traction control (TCS), stability control (VDC: Vehicle Dynamics Control), etc., and controls the brake actuator 25 to control the hydraulic pressure of the wheel cylinder 23. , Switch to pressure increase, hold pressure, and pressure reduction. That is, in the anti-skid control, the hydraulic pressure of each wheel cylinder 23 is controlled according to the number of wheel rotations during braking to suppress the tire locking tendency. Further, in the traction control, the hydraulic pressure of each wheel cylinder 23 is controlled according to the slip ratio of the drive wheel to suppress the wheel spin tendency of the drive wheel. Further, in the stability control, the hydraulic pressure of each wheel cylinder 23 is controlled according to the amount of side slip of the vehicle body, and the side slip tendency and the bottom swing tendency of the vehicle body are suppressed. In addition, an abnormality diagnosis of the brake actuator 25 is performed by the abnormality diagnosis system. Further, when an abnormality occurs in the electric booster 24, the brake actuator 25 is driven and controlled to assist the driver's brake operation (boost action).

Next, the electric booster 24 will be described.
FIG. 2 is a schematic configuration diagram of the electric booster 24.
One end of the brake pedal 21 is pivotally supported by the vehicle body so that the brake pedal 21 can rotate. The brake operation of the driver is input to the pedal pad 21a at the other end, and the end between the one end and the other end is rotated to the push rod 21c via the clevis 21b. It is pivotally supported. A stroke sensor 26 is provided at one end of the brake pedal 21. The push rod 21c is connected to a tandem master cylinder 22 fixed to the vehicle body. In the master cylinder 22, a secondary return spring 22a, a secondary piston 22b, a primary return spring 22c, and a primary piston 22d are sequentially inserted.

  A cylindrical portion 22e is formed at the rear end of the primary piston 22d, and a rod that biases the push rod 21c to the backward side between the push rod 21c located inside the cylindrical portion 22e and the primary piston 22d. A return spring 22f is interposed. A predetermined gap for regenerative enhancement control is provided between the primary piston 22d and the push rod 21c, and the push rod 21c moves forward against the repulsive force of the rod return spring 22f. When the front end comes into contact with the rear end of the primary piston 22d, the primary piston 22d also moves forward as the push rod 21c moves forward.

The electric booster 24 includes an electric motor 41 that is fixed to a housing (not shown), a ball screw mechanism 42 that is provided in the housing, converts the rotational motion of the electric motor 41 into linear motion, and applies thrust to the primary piston 22d, It has.
The electric motor 41 includes a stator 43 and a rotor 44 disposed inside the stator 43 and rotatably supported. The ball screw mechanism 42 is a cylindrical rotating member 45 connected to the rotor 44, and a cylinder that is provided around the primary piston 22d and whose outer peripheral surface is screwed to the inner peripheral surface of the rotating member 45 via a plurality of balls 46. And a linearly moving member 47 having a shape. The linear motion member 47 is prevented from rotating by the housing in a state in which the linear motion member 47 can advance and retreat in the axial direction, and a flange 48 that contacts the rear end of the cylindrical portion formed on the rear side of the primary piston 22d is provided on the inner peripheral surface. It is formed.

  With the above structure, when the rotating member 45 is rotated by the electric motor 41, the linear movement member 47 that is prevented from rotating moves forward and backward in the axial direction, so that the primary piston 22d moves forward and backward regardless of the position of the push rod 21c. That is, even if the position of the push rod 21c is constant, if the electric motor 41 is rotated forward, for example, to move the linear motion member 47 forward, the primary piston 22d moves forward against the repulsive force of the primary return spring 22c. Even if the position of the push rod 21c is constant, when the electric motor 41 is reversed, for example, and the linear motion member 47 is retracted, the primary piston 22d is retracted by the repulsive force of the primary return spring 22c.

  Therefore, when only the friction brake is used, if the linear motion member 47 is advanced by the stroke sensor 26 according to the operation amount of the brake pedal 21, the driver's brake operation when the hydraulic pressure of the master cylinder 22 rises is assisted. (Boost action) In addition, when the regenerative emphasis control is executed by combining the friction brake and the regenerative brake, if the linear motion member 47 is retracted according to the regenerative brake amount, the hydraulic pressure of the master cylinder 22 decreases even if the brake operation amount remains constant. To do. When the vehicle stops, the amount of regenerative braking decreases, so that the linear motion member 47 is advanced to increase the hydraulic pressure in the master cylinder 22. Further, when the drive control of the electric booster 24 is stopped, when the tip of the push rod 21c comes into contact with the rear end of the primary piston 22d, the primary piston 22d moves forward in accordance with the advance of the push rod 21c, and the liquid in the master cylinder 22 The pressure rises.

The above is an explanation of the electric booster 24.
Next, the brake actuator 25 will be described.
FIG. 3 is a schematic configuration diagram of the brake actuator 25.
Here, in order to distinguish the front, rear, left, and right wheels, a suffix FL is added to a symbol related to the front left wheel, a suffix FR is added to a symbol related to the front right wheel, and a suffix RL is added to a symbol related to the rear left wheel. In the following description, the suffix RR is attached to the reference numerals related to the rear right wheel.

The brake actuator 25 is interposed between the master cylinder 22 and the wheel cylinders 23FL to 23RR.
The master cylinder 22 is a tandem type that creates two hydraulic pressures according to the driver's pedaling force. The master cylinder 22 transmits the primary side to the front left and rear right wheel cylinders 23FL and 23RR, and the secondary side transmits the right front wheel and A diagonal split system is used to transmit to the left rear wheel cylinders 23FR and 23RL.

Each of the wheel cylinders 23FL to 23RR is built in a disc brake that generates a braking force by clamping a disc rotor with a brake pad, or a drum brake that generates a braking force by pressing a brake shoe against the inner peripheral surface of the brake drum. is there.
The brake actuator 25 uses a brake fluid pressure control circuit used for anti-skid control (ABS), traction control (TCS), stability control (VDC: Vehicle Dynamics Control), etc. Regardless, the hydraulic pressure of each wheel cylinder 23FL to 23RR can be increased, held and reduced.
The primary side includes a first gate valve 51A, an inlet valve 52FL (52RR), an accumulator 53, an outlet valve 54FL (54RR), a second gate valve 55A, a pump 56, and a damper chamber 57.

  The first gate valve 51A is a normally open valve that can close the flow path between the master cylinder 22 and the wheel cylinder 23FL (23RR). The inlet valve 52FL (52RR) is a normally open valve that can close the flow path between the first gate valve 51A and the wheel cylinder 23FL (23RR). The accumulator 53 is communicated between the wheel cylinder 23FL (23RR) and the inlet valve 52FL (52RR). The outlet valve 54FL (54RR) is a normally closed valve that can open the flow path between the wheel cylinder 23FL (23RR) and the accumulator 53. The second gate valve 55A is a normally-closed type valve that can open a flow path that communicates between the master cylinder 22 and the first gate valve 51A and between the accumulator 53 and the outlet valve 54FL (54RR). The pump 56 communicates the suction side between the accumulator 53 and the outlet valve 54FL (54RR), and communicates the discharge side between the first gate valve 51A and the inlet valve 52FL (52RR). The damper chamber 57 is provided on the discharge side of the pump 56, suppresses the pulsation of the discharged brake fluid, and weakens the pedal vibration.

Similarly to the primary side, the secondary side also has a first gate valve 51B, an inlet valve 52FR (52RL), an accumulator 53, an outlet valve 54FR (54RL), a second gate valve 55B, a pump 56, A damper chamber 57.
The first gate valves 51A and 51B, the inlet valves 52FL to 52RR, the outlet valves 54FL to 54RR, and the second gate valves 55A and 55B are two-port, two-position switching, single solenoid, and spring offset type electromagnetic operations, respectively. It is a valve. The first gate valves 51A and 51B and the inlet valves 52FL to 52RR open the flow path at the non-excited normal position, and the outlet valves 54FL to 54RR and the second gate valves 55A and 55B are at the non-excited normal position. The flow path is closed.

The accumulator 53 is a spring-type accumulator in which a compression spring is opposed to a cylinder piston.
The pump 56 is a positive displacement pump such as a gear pump or a piston pump that can ensure a substantially constant discharge amount regardless of the load pressure.
With the above configuration, the primary side will be described as an example. When the first gate valve 51A, the inlet valve 52FL (52RR), the outlet valve 54FL (54RR), and the second gate valve 55A are all in the non-excited normal position. Then, the hydraulic pressure from the master cylinder 22 is transmitted as it is to the wheel cylinder 23FL (23RR) and becomes a normal brake.

  Even when the brake pedal is not operated, the first gate valve 51A is excited and closed while the inlet valve 52FL (52RR) and the outlet valve 54FL (54RR) are kept in the non-excited normal position. The second gate valve 55A is excited and opened, and the pump 56 is further driven to suck the hydraulic pressure of the master cylinder 22 through the second gate valve 55A, and the discharged hydraulic pressure is set to the inlet valve 52FL (52RR). ) To the wheel cylinder 23FL (23RR) to increase the pressure.

  When the first gate valve 51A, the outlet valve 54FL (54RR), and the second gate valve 55A are in the non-excited normal position, if the inlet valve 52FL (52RR) is excited and closed, the wheel cylinder 23FL (23RR) ) To the master cylinder 22 and the accumulator 53 are blocked, and the hydraulic pressure of the wheel cylinder 23FL (23RR) is maintained.

  Further, when the first gate valve 51A and the second gate valve 55A are in the non-excited normal position, the inlet valve 52FL (52RR) is excited and closed, and the outlet valve 54FL (54RR) is excited and opened. The hydraulic pressure in the wheel cylinder 23FL (23RR) flows into the accumulator 53 and is reduced. The hydraulic pressure that has flowed into the accumulator 53 is sucked by the pump 56 and returned to the master cylinder 22.

Also on the secondary side, the normal braking, pressure increasing, holding, and pressure reducing operations are the same as the operations on the primary side, and detailed description thereof will be omitted.
Therefore, the actuator controller 34 controls the drive of the first gate valves 51A and 51B, the inlet valves 52FL to 52RR, the outlet valves 54FL to 54RR, the second gate valves 55A and 55B, and the pump 56. The hydraulic pressure of the wheel cylinders 23FL to 23RR is increased, held and reduced.

In this embodiment, a diagonal split method is used in which the brake system is divided into front left / rear right and front right / rear left. However, the present invention is not limited to this, and it is divided into front left / right and rear left / right. A front / rear split method may be employed.
Further, in the present embodiment, the spring-shaped accumulator 53 is employed, but the present invention is not limited to this, and brake fluid extracted from each wheel cylinder 23FL to 23RR is temporarily stored to efficiently reduce pressure. Therefore, any type such as a weight type, a gas compression direct pressure type, a piston type, a metal bellows type, a diaphragm type, a bladder type, and an in-line type may be used.

  In the present embodiment, the first gate valves 51A and 51B and the inlet valves 52FL to 52RR open the flow path at the non-excited normal position, and the outlet valves 54FL to 54RR and the second gate valves 55A and 55B are non-excited. Although the flow path is closed at the normal excitation position, the present invention is not limited to this. In short, since it is only necessary to open and close each valve, the first gate valves 51A and 51B and the inlet valves 52FL to 52RR open the flow path at the excited offset position, and the outlet valves 54FL to 54RR and the second gate are opened. The valves 55A and 55B may close the flow path at the excited offset position.

The above is the description of the brake actuator 25.
The brake controller 32 is composed of, for example, a microcomputer, and executes a brake control process every predetermined time (for example, 10 msec).
FIG. 4 is a flowchart showing a brake control process.
In step S101, abnormality diagnosis of the friction brake system is performed. In the present embodiment, there are two systems, an electric booster 24 and a brake actuator 25, and communication is possible with each controller via a communication line. Each controller is provided with an abnormal state detection / determination function, and when it is diagnosed that an abnormality has occurred in its own braking force generation function, the fact that the abnormality has occurred is transmitted. In step S101, abnormality diagnosis is executed using this signal. Further, when a signal line disconnection / short circuit is detected and abnormality diagnosis of a specific friction brake system cannot be performed, it is diagnosed that the brake system is abnormal.

  In step S102, it is determined whether or not any of the plurality of systems of friction brakes is abnormal. Here, the plurality of systems of the friction brake refers to two systems, that is, the system of the electric booster 24 and the system of the brake actuator 25. Here, when there is no abnormality in any system of the friction brake, that is, when the electric booster 24 and the brake actuator 25 are all normal, the process proceeds to step S103. On the other hand, when there is an abnormality in at least one system of the friction brake, that is, there is an abnormality in either the electric booster 24 or the brake actuator 25, the process proceeds to step S105.

In step S103, when the charge limit is set in the processes of steps S106 and S113 described later, the charge limit is canceled because the abnormal friction brake system has been repaired, and normal charging is performed. Return to control.
In the following step S104, the target braking force corresponding to the driver's brake operation amount is calculated, and the friction brake and the regenerative brake are optimally controlled according to the target braking force, thereby executing the normal regenerative cooperative control. To return to a predetermined main program. That is, the EV controller 33 determines the target regenerative torque in consideration of the vehicle speed, the motor temperature, the battery charge amount, the battery temperature, etc., and performs the regenerative brake control by the power generation operation of the motor 13. Further, the brake controller 32 determines the target hydraulic pressure according to a value obtained by subtracting the target regenerative torque from the target braking force according to the brake operation amount of the driver, and performs the friction brake control via the electric booster 24.

  In step S105, it is determined whether or not all the systems of the friction brake are abnormal. Here, when there is an abnormality only in one of the systems of the friction brake, that is, there is an abnormality only in one of the electric booster 24 and the brake actuator 25, and the other is normal, the process proceeds to step S106. On the other hand, when all the systems of the friction brake are abnormal, that is, when both the electric booster 24 and the brake actuator 25 are abnormal, the process proceeds to step S113.

In step S106, a charge amount margin threshold SOC _LIM that allows charging from the regenerative brake and the external power supply is set. During regenerative cooperative braking, charging from the regenerative brake and the external power supply is allowed when the state of charge SOC of the lithium ion battery 11 is below the charge amount allowance threshold SOC _LIM . Moreover, at the time of charge control by the external power supply, the charge is stopped when the charge is completed up to the charge amount margin threshold SOC _LIM .

Here, the setting of the charge amount margin threshold SOC _LIM will be described.
The maximum vehicle speed in the design is defined as V _MAX, and the allowable charge amount upper limit value (maximum charge capacity) of the lithium ion battery 11 is defined as SOC _MAX . Further, 0 from the maximum vehicle speed _{V MAX} only the regenerative brake on a flat road [km / h] the amount of charge needed to decelerate to the _{E 1,} 0 in, for example, from 80 downhill downward slope is 15% [km / the amount of charge required to decelerate to h] and E _2, setting the charge amount margin threshold SOC _LIM according to the following equation.
SOC _LIM = SOC _MAX -E _1- (n × E ₂ )

Here, n is arbitrarily set as the number of times that braking is possible when abnormality occurs in all systems of the friction brake. On a flat road, when accelerating, it consumes more energy than is recovered when decelerating, so that more braking is possible.
In addition, when it is assumed that the charge amount SOC reaches the charge amount allowable upper limit SOC _MAX by repeatedly decelerating on a continuous downward slope and the like, and the energy continues to increase, the vehicle is decelerated to the stop state, Holds stopped.

In step S107, a motor temperature margin threshold value tm _LIM that enters motor output restriction is set. Assuming that the allowable motor temperature upper limit during normal control is tm _MAX , the motor temperature margin threshold tm _LIM set in this process is set as follows, for example. In case of reaching tm _MAX when the deceleration from 80 to 0 [km / h] is repeated n times continuously at a normal vehicle speed V _MAX only at regenerative brake at normal temperature and 0 [km / h], 15% down slope Is calculated in advance by actual running or simulation, and the start temperature is set as a motor temperature margin threshold value tm _LIM . That is, a value obtained by decreasing the motor temperature allowable upper limit value tm _MAX by the amount of increase in motor temperature when the motor 13 performs a predetermined regeneration is set as the motor temperature margin threshold value tm _LIM .

When the motor temperature tm reaches the motor temperature margin threshold tm _LIM , the power running torque limit value Tm _tm and the regenerative torque limit value Tr _tm of the motor 13 are set so that the temperature does not rise any further. These limit values may be values that vary depending on the vehicle speed. As a result, since the power running torque Tm and the regenerative torque Tr of the motor 13 are appropriately limited, an increase exceeding the motor temperature margin threshold value tm _LIM is suppressed, and even if an abnormality occurs in all systems of the friction brake, The deceleration due to regenerative braking can be generated without reaching the allowable motor temperature upper limit value tm _MAX .

In step S108, temperature control of the lithium ion battery 11 is performed. Since the temperature of the lithium ion battery 11 in some cases at extremely low temperature and high temperature can not sufficiently regenerative braking, extremely low temperature equal to or lower than a predetermined battery temperature allowable lower limit tb _MIN raises the temperature of the lithium ion battery 11 . In addition, a restriction is placed on the charge / discharge amount at a high temperature that is equal to or higher than a predetermined battery temperature margin threshold tb _LIM .

First, at a very low temperature, if the lithium ion battery 11 has a heater for adjusting the temperature, the heater is operated to raise the temperature to the normal temperature range. Further, the power running torque is added to the driver required torque, and the braking torque of the friction brake is increased and offset by that amount (torque massing state), so that a large amount of current flows through the lithium ion battery 11 to cause self-heating. The temperature rise of the battery temperature tb is promoted. Note that the maximum amount of addition is set to a value that does not cause the brake friction material of the wheel cylinder 23 to fade due to continuous braking. The amount of addition to the power running torque and the friction torque at this time is defined as Ta _tb .

On the other hand, at the time of high temperature, similarly to the torque limit control at the time of high temperature of the motor in step S107, a battery temperature margin threshold value tb _LIM smaller than the normal battery temperature allowable upper limit value tb _MAX is set. Control so as not to exceed the above. Here, a value obtained by reducing the battery temperature allowable upper limit value tb _MAX by a battery temperature increase when the motor 13 performs a predetermined regeneration is set as the battery temperature margin threshold value tb _LIM . The power running torque limit value at this time is Tm _tb , and the regenerative torque limit value is Tr _tb .

In step S109, discharge control of the lithium ion battery 11 is performed. In step S106, although the charging amount margin threshold _{SOC LIM} is set, if the current state of charge SOC is charged amount margin threshold _{SOC LIM} or performs the discharge control to be below the charge amount margin threshold _{SOC LIM} . Specifically, as the difference between the current charge amount SOC and the charge amount margin threshold SOC _LIM is larger, the driving force is added to the driver request, and the friction braking torque is increased by that amount to cancel (torque In a state of being clouded), the discharge of the lithium ion battery 11 is promoted. Note that the maximum amount of addition is set to a value that does not cause the brake friction material of the wheel cylinder 23 to fade due to continuous braking. The amount of addition to the power running torque and the friction torque at this time is Ta _SOC .
Ta _SOC = f (SOC-SOC _LIM )

In addition, when the current charge amount SOC is equal to or greater than the charge amount margin threshold SOC _LIM , the power consumption of other electrical devices is increased simultaneously to reduce the charge amount SOC. Specifically, the air conditioner and the seat heater are operated, and the air conditioner is simultaneously operated to promote the power consumption of the re-12V battery 35 and the power consumption of the lithium ion battery 11 without greatly changing the room temperature. Let In addition, when equipped with a discharge (heat radiating) device that discharges electricity by converting it into heat, or a capacitor that accumulates current for braking and driving temporarily, the current is positively passed, and the lithium ion battery 11 The reduction of the charge amount SOC is promoted.

  In step S110, it is estimated in advance whether or not all the systems of friction brakes that are currently operable become inoperable. For example, consider a case where an abnormality has already occurred in the system of the electric booster 24 and an abnormality has occurred in the DC / DC converter 36 that supplies power to the brake actuator 25 from that state (double failure). That is, when it is detected that the power supply voltage supplied to the brake actuator 25 has dropped to the supply voltage of the 12V battery 35, it is estimated that the system of the brake actuator 25 also becomes inoperable after a certain time has elapsed.

In this case, the motor output and the friction braking torque are controlled so that the vehicle speed is less than the vehicle speed threshold V _LIM (for example, 80 km / h) at which the motor 13 can generate the maximum regenerative torque quickly. That is, the power running torque limit value Tm _V is set when the current vehicle speed V is equal to or higher than the vehicle speed threshold value V _LIM . The power torque limit value Tm _V is positive driver acceleration demand (+), the deceleration request negative value - reduction in the when, predetermined deceleration (e.g. -1.5m / ^{s 2)} () Power running torque that can be performed. As a result, the vehicle can be decelerated to the vehicle speed threshold value V _LIM with a predetermined deceleration regardless of the driver's intention to accelerate. In addition, if there is a deceleration request exceeding a predetermined deceleration, it is reflected as it is.

In step S111, a final motor torque command value _TF is determined in accordance with each limit value calculated in the processes in steps S106 to S110. First, when the driver is operating the accelerator, a final motor torque command value _TF is determined as shown below. Here, Td is a driver's required torque determined according to the driver's accelerator operation amount. Each value is a positive value.
T _F = min [Tm _tm , Tm _tb , Tm _V , Td + max (Ta _tb , Ta _SOC )]

When the driver is operating the brake, the final motor torque command value _TF is determined as shown below. Here, Td is a driver's required torque determined according to the driver's brake operation amount. Each value is a negative value.
T _F = max [Tr _tm , Tr _tb , Td + min (Ta _tb , Ta _SOC )]

In step S112, the amount of friction braking torque to be added to cancel the power running torque in steps S108 and S109 is calculated. Since there is a case where the addition cannot be sufficiently performed due to the limitation, the addition friction braking torque Ta _fb is calculated for the amount that can be added to the driver request torque. Furthermore, because it may not be realized motor torque limit value Tm _V for realizing the vehicle speed limit in step S110, to compensate for that amount in the friction brake.
Ta _fb = max [ _TF− Td, 0]
Ta _fb = max [Ta _fb , −min {Tm _V −min ( _TF , 0), 0}]
In the brake controller 32, a value obtained by subtracting _TF from the braking request torque (negative value Td) of the driver is generated as the braking torque of the friction brake (regenerative cooperative control). This Ta _fb is a positive value (+). In this case, _Tafb is further added to generate the braking torque of the friction brake.

Next, a case where all the systems of the friction brake are disabled will be described.
In step S113, only the charge restriction by the regenerative brake is canceled for the charge restriction set in step S106. When charging from an external power supply, the charging restriction set in step S106 is continued. Note that the charging limit is set in this process in preparation for the case where the process of step S113 is directly executed without performing step S106 and subsequent steps, or when the charging limit is initialized by detaching or igniting the lithium ion battery 11 or the like. May be. As a result, the battery charge SOC is allowed to be charged by the regenerative brake beyond the charge charge margin threshold SOC _LIM .

In step S114, the driver's required braking torque is calculated. Until an abnormality occurs in all systems of the friction brake, the brake controller 32 calculates the driver requested braking force using the friction brake as a master, and the EV controller 33 that controls the braking / driving force of the motor 13 serves as the slave for the requested braking torque. Realize. However, after it is diagnosed in step S103 that an abnormality has occurred in all systems of the friction brake, the EV controller 33 calculates the driver required braking force independently.
At this time, the required braking torque Td determined by the EV controller 33 according to the driver's brake operation is set to be smaller than the required braking torque Td determined by the brake controller 32 according to the driver's brake operation.

FIG. 5 is a map used for calculating the required torque Td.
When normal, as shown by the broken line, the required braking torque (absolute value) increases as the brake operation amount increases. On the other hand, when an abnormality occurs in all the systems, as indicated by the solid line, the required braking torque (absolute value) increases in a smaller range than in normal operation as the brake operation amount increases. That is, the inclination is reduced. Further, when the amount of brake operation by the driver is equal to or greater than a predetermined value St, the maximum braking torque Td _MAX is limited.

In step S115, in preparation for the case where the vehicle speed V cannot be lowered to the vehicle speed threshold value V _LIM in step S110, when the vehicle speed V is higher than the vehicle speed threshold value V _LIM , the vehicle speed V is set so as to quickly become the vehicle speed threshold value V _LIM or less. Implement control to reduce That is, the limit of the power torque of the motor 13 as in step S110, sets the power running torque limit value Tm _V.
In step S116, the estimated deceleration value Ge estimated to be generated by the regenerative braking is compared with the actually detected deceleration detection value Gd. The detected deceleration value Gd is larger than the estimated deceleration value Ge, and the difference is detected. Is greater than a predetermined threshold, the regeneration stop flag is set to fs = 1. In the initial setting, the regeneration stop flag is set to fs = 0.

  The deceleration detection value Gd may be obtained by differentiating the rotational speed of the motor 13 or the like, and if there is a longitudinal acceleration sensor, correction based on the road surface gradient may be performed to improve detection accuracy. If this is not possible, a change in weight or gradient is assumed, and a threshold is set so that the generation of regenerative braking force will not be inadvertently stopped even if there are variations.

In step S117, the regeneration stop flag fs is referred to, and as shown in the following formula, the output of the motor 13 is determined and controlled, and then the process returns to a predetermined main program.
Td = if [fs = 1, 0, min (Td, Tm _V )]
Here, when the regeneration stop flag is fs = 1, 0 is returned to the driver request torque Td, and when the regeneration stop flag is fs = 0, min (Td, Tm _V ) is set to the driver request torque Td. return. That is, the regenerative brake is stopped when the regenerative brake and the friction brake are double braked. Accordingly, for example, when it is not known whether the communication line is disconnected and the friction brake is operating, the friction brake is operated, and the double brake of the regenerative brake and the friction brake is prevented.

The above is the description of the brake control process based on the flowchart of FIG.
In the present embodiment, the two systems in which the system of the electric booster 24 and the system of the brake actuator 25 are arranged in series have been described as the plurality of systems of the friction brake. However, the present invention is not limited to this. In addition, the present invention may be applied to a system having a plurality of systems arranged in parallel, such as an electric brake.

<Action>
Next, the operation of the first embodiment will be described.
There are situations where regenerative braking is limited in operation. For example, when the lithium ion battery 11 is fully charged or the motor 13 or the lithium ion battery 11 is overheated, the operation of the regenerative brake is limited to protect the motor 13 and the lithium ion battery 11. There is a need. Therefore, there is a possibility that the operation of the regenerative brake may be limited even in a situation where an abnormality occurs in the friction brake including a plurality of systems and a backup by the regenerative brake is necessary.

Therefore, in the present embodiment, when an abnormality is detected in some brake systems in the friction brake (determination in step S105 is “No”), in preparation for a situation in which an abnormality occurs in all brake systems, the charging permission condition is set. The state of the charging system is controlled in advance so as to satisfy.
First, a value obtained by reducing the charge amount allowable upper limit value SOC _{MAX of} the lithium ion battery 11 by the charge amount when the motor 13 performs a predetermined regeneration is set as the charge amount margin threshold SOC _LIM . Then, when the state of charge SOC is below the charge amount margin threshold SOC _LIM, when allowing charging from regenerative braking and the external power source, it is charged until the charge amount margin threshold SOC _LIM, whether charged by regenerative, external If it is charging from the charging device, further charging is stopped (step S106).

As a result, a free capacity with respect to the charge amount allowable upper limit SOC _MAX is secured, so that even if an abnormality occurs in all the systems of the friction brake, a predetermined sufficient regeneration is allowed. The back performance can be secured. In addition, in anticipation of the increase in the charge amount when the regeneration is executed, by allowing a margin for the charge amount allowable upper limit SOC _{MAX by} that amount, even if an abnormality occurs in all systems of the friction brake, Since the predetermined sufficient regeneration is allowed, the back performance by the regenerative brake can be ensured.

Further, a value that is reduced from the motor temperature allowable upper limit value tm _MAX by a motor temperature increase when the motor 13 performs a predetermined regeneration is set as the motor temperature margin threshold value tm _LIM . When the motor temperature is equal to or greater than the motor temperature margin threshold value tm _LIM , if the driver is operating the accelerator, the power running torque of the motor 13 is limited by the power running torque limit value Tm _tm , and the driver operates the brake. If this is done, the regenerative torque of the motor 13 is limited by the regenerative torque limit value Tr _tm (steps S107 and S111).

Thereby, since the temperature rise of the motor 13 can be suppressed, even if an abnormality occurs in all systems of the friction brake, the charging permission condition regarding the motor temperature is satisfied and the regeneration operation is allowed. Backup performance by regenerative braking can be ensured. In addition, in anticipation of the motor temperature rise when the regeneration is executed, by giving a margin to the motor temperature allowable upper limit tm _MAX by that amount, even if an abnormality occurs in all systems of the friction brake, Since the predetermined sufficient regeneration is allowed, the back performance by the regenerative brake can be ensured.

Further, a value that is decreased from the battery temperature allowable upper limit value tb _MAX by the battery temperature increase when the motor 13 performs a predetermined regeneration is set as the battery temperature margin threshold Tm _tb . When the temperature of the lithium ion battery 11 is equal to or higher than the battery temperature margin threshold tb _LIM , if the driver is operating the accelerator, the power running torque of the motor 13 is limited by the power running torque limit value Tm _tb for driving. If the person is operating the brake, the regenerative torque of the motor 13 is limited by the regenerative torque limit value Tr _tb (steps S108 and S111).

Thereby, since the temperature rise of the lithium ion battery 11 can be suppressed, even if an abnormality occurs in all systems of the friction brake, the charging permission condition regarding the battery temperature is satisfied and the regeneration operation is allowed. Therefore, the backup performance by regenerative braking can be secured. In addition, in anticipation of the increase in battery temperature when regeneration is performed, by allowing a margin to the battery temperature allowable upper limit tb _MAX by that amount, even if an abnormality occurs in all systems of the friction brake, Since the predetermined sufficient regeneration is allowed, the back performance by the regenerative brake can be ensured.

On the other hand, the temperature of the lithium ion battery 11 when it is less than the battery temperature allowable lower limit tb _MIN is or actuates the heater for temperature control, or to increase the power torque of the motor 13 (step S108, S 111). Here, when the power running torque of the motor 13 is increased, in order to realize the driver's required driving torque, the braking torque of the friction brake is increased correspondingly and canceled (step S112).

  As a result, the temperature rise of the battery temperature can be promoted, so that even if an abnormality occurs in all systems of the friction brake, the charging permission condition regarding the battery temperature is satisfied and the regeneration operation is allowed. Backup performance by regenerative braking can be ensured. Moreover, the required drive torque according to the driver's accelerator operation can be realized while ensuring the backup performance by the regenerative brake.

In addition, when the charge amount SOC is equal to or greater than the charge amount margin threshold SOC _LIM , an electrical device such as a heater or an air conditioner is operated, a current is passed through the discharger or capacitor, or the power running torque of the motor 13 is increased. (Steps S109 and S111). Here, when the power running torque of the motor 13 is increased, in order to realize the driver's required driving torque, the braking torque of the friction brake is increased correspondingly and canceled (step S112).

  Thereby, since the discharge of the lithium ion battery 11 can be promoted, even if an abnormality occurs in all systems of the friction brake, the charging permission condition related to the battery temperature is satisfied and the regenerative operation is allowed. Therefore, backup performance by regenerative braking can be secured. Moreover, the required drive torque according to the driver's accelerator operation can be realized while ensuring the backup performance by the regenerative brake.

Further, it is assumed that the occurrence of an abnormality in all the brake systems is detected in advance from the state in which the abnormality of some brake systems in the friction brake is detected. In this case, before all the systems of the friction brake become inoperable, the motor 13 quickly reduces the vehicle speed threshold value V _{LIM that} can generate the maximum regenerative torque (step S110). Thereby, even if an abnormality occurs in all systems of the friction brake, at least the regenerative brake by the maximum regenerative torque can be operated, and sufficient brake performance can be ensured.

If an abnormality has occurred in all systems in the friction brake (determination in step S105 is “Yes”), the charging restriction by the regenerative brake is first canceled (step S113). At this time, in the regenerative cooperative control performed mainly by the brake controller 32, since the reliability is lowered, the regenerative cooperative control is stopped, and the EV controller 33 executes the regenerative brake control alone. Thereby, highly reliable brake performance can be ensured. Further, when the vehicle speed V is higher than the vehicle speed threshold _{V LIM} causes quickly so that the following vehicle speed threshold _{V LIM,} decrease the vehicle speed V (step S115).

  Further, when an abnormality in all brake systems in the friction brake is detected, the regenerative torque due to the power generation operation of the motor corresponding to the driver's brake operation is made smaller than when no abnormality in all brake systems is detected ( Step S114). Accordingly, it is possible to make the driver surely recognize that an abnormality has occurred in the friction brake in the brake system and the braking force is difficult to be generated, and prompt repair can be promoted.

  In addition, it may not be possible to determine whether or not the friction brake is inoperable due to multiple failures in the communication system, etc. This is simply because the result of the abnormality diagnosis is unknown, and the friction brake actually operates. It may be possible. In this case, only the regenerative brake should be operated, but the friction brake is also operated at the same time, resulting in double braking. Therefore, when the vehicle deceleration estimated value Ge estimated to be generated by the regenerative braking force is larger than the actually detected vehicle deceleration detected value Gd and the difference is larger than a predetermined value, the motor 13 The control of the regenerative braking force by the power generation operation is stopped (step S116). Thus, for example, when it is unclear whether the communication line is disconnected and the friction brake is operating, the friction brake is actually operating, resulting in double braking of the regenerative brake and the friction brake. This can be prevented.

  As described above, the brake pedal 21, the master cylinder 22, the wheel cylinder 23, the electric booster 24, and the brake actuator 25 correspond to “friction brake”, and the motor 13 corresponds to “electric motor”. Further, the processes in steps S101 and S102 correspond to “abnormality detection means”, and the processes in steps S106 to 109 and S111 to S113 correspond to “abnormality detection state control means”. Further, the processing of steps S114 to S116 corresponds to “braking force control means when abnormality is detected”.

"effect"
Next, the effect of the main part in 1st Embodiment is described.
(1) The vehicle brake control device according to the present embodiment drives a vehicle during a power running operation by a friction brake including a plurality of brake systems, a lithium ion battery 11, and electric power from the lithium ion battery 11, and during a power generation operation. And a motor 13 that charges the lithium ion battery 11 by regeneration. The motor 13 is allowed to regenerate when the state of the charging system satisfies a predetermined charging permission condition. And when the abnormality of some brake systems in a friction brake is detected, the state of a charge system is controlled so that charge permission conditions may be satisfy | filled.

  In this way, when an abnormality in a part of the brake system in the friction brake is detected, the state of the charging system is controlled so as to satisfy the charging permission condition, so even if an abnormality has occurred in all the systems of the friction brake, Regeneration by the power generation operation of the motor is allowed. That is, since the backup performance by the regenerative brake can be ensured, the reliability of the backup performance can be improved.

(2) In the vehicle brake control device according to the present embodiment, the charge permission condition is that the charge amount SOC of the lithium ion battery 11 is lower than the charge amount allowable upper limit SOC _MAX . Then, a charge amount margin threshold SOC _LIM smaller than the charge amount allowable upper limit SOC _MAX is set, and when the battery charge amount SOC is equal to or larger than the charge amount margin threshold SOC _LIM , the motor 13 corresponding to the driver's accelerator operation is set. Increase the power running torque by Ta _SOC . Further, the braking torque is increased by the amount of Ta _SOC that increases the power running torque of the motor 13.

  In this way, by increasing the power running torque and offsetting the amount by increasing the braking torque, the discharge of the lithium ion battery 11 can be promoted. Therefore, even if an abnormality occurs in all systems of the friction brake, the charging permission condition regarding the charge amount SOC is satisfied and the regenerative operation is allowed, so that the backup performance by the regenerative brake can be ensured.

(3) In the vehicle brake control device according to the present embodiment, the charge permission condition is that the charge amount SOC of the lithium ion battery 11 is lower than the charge amount allowable upper limit SOC _MAX . Then, a charge amount margin threshold SOC _LIM smaller than the charge amount allowable upper limit SOC _MAX is set, and when the charge amount SOC of the lithium ion battery 11 is equal to or greater than the charge amount margin threshold SOC _LIM , the power consumption in the electrical equipment is increased. To do.
Thus, discharge of the lithium ion battery 11 can be promoted by increasing the power consumption of the electrical equipment. Therefore, even if an abnormality occurs in all systems of the friction brake, the charging permission condition regarding the charge amount SOC is satisfied and the regenerative operation is allowed, so that the backup performance by the regenerative brake can be ensured.

(4) The vehicle brake control device according to the present embodiment has a charge amount margin threshold SOC that is a value obtained by reducing the charge amount allowable upper limit value SOC _MAX by the amount of charge when the motor 13 performs a predetermined regeneration. Set as _LIM .
In this way, in anticipation of the increase in the charge amount when the regeneration is executed, even if an abnormality has occurred in all systems of the friction brake by giving a margin to the charge amount allowable upper limit SOC _{MAX by} that amount, Since predetermined sufficient regeneration is allowed, the back performance by the regenerative brake can be ensured.

(5) The vehicle brake control device according to the present embodiment prohibits charging of the lithium ion battery 11 from the external charging device when the charge amount SOC of the lithium ion battery 11 is equal to or greater than the charge amount margin threshold SOC _LIM .
As described above, when the charge amount SOC is equal to or greater than the charge amount margin threshold SOC _LIM , the free capacity with respect to the charge amount allowable upper limit SOC _MAX is ensured by prohibiting the charging by the external charging device. Therefore, even if an abnormality occurs in all systems of the friction brake, predetermined sufficient regeneration is allowed, so that the back performance by the regenerative brake can be ensured.

(6) The vehicle brake control device according to the present embodiment prohibits charging of the lithium ion battery 11 from the motor 13 when the charge amount SOC of the lithium ion battery 11 is equal to or greater than the charge amount margin threshold SOC _LIM .
In this way, when the charge amount SOC is equal to or greater than the charge amount margin threshold SOC _LIM , the free capacity for the charge amount allowable upper limit SOC _MAX is ensured by prohibiting charging by regeneration. Therefore, even if an abnormality occurs in all systems of the friction brake, predetermined sufficient regeneration is allowed, so that the back performance by the regenerative brake can be ensured.

(7) In the vehicle brake control device according to the present embodiment, the charge permission condition is that the temperature of the motor 13 is lower than the motor temperature allowable upper limit value tm _MAX . Then, a motor temperature margin threshold value tm _LIM smaller than the motor temperature allowable upper limit value tm _MAX is set, and when the temperature of the motor 13 is equal to or higher than the motor temperature margin threshold value tm _LIM , the power running of the motor 13 according to the driver's accelerator operation is performed. The torque is reduced or the regenerative torque of the motor 13 corresponding to the driver's brake operation is reduced.
Thus, the temperature increase of the motor 13 can be suppressed by reducing the power running torque or the regenerative torque. Therefore, even if an abnormality occurs in all systems of the friction brake, the charging permission condition regarding the motor temperature is satisfied and the regenerative operation is allowed, so that the backup performance by the regenerative brake can be ensured.

(8) The vehicle brake control device according to the present embodiment has a motor temperature margin threshold value obtained by reducing the motor temperature allowable upper limit value tm _MAX by a value corresponding to an increase in motor temperature when the motor 13 performs a predetermined regeneration. Set as tm _LIM .
In this way, even if an abnormality occurs in all systems of the friction brake by allowing for the motor temperature allowable upper limit tm _MAX by that amount in anticipation of the motor temperature rise when the regeneration is executed. Since predetermined sufficient regeneration is allowed, the back performance by the regenerative brake can be ensured.

(9) In the vehicle brake control device according to the present embodiment, the charge allowable condition is that the temperature of the lithium ion battery 11 is lower than the battery temperature allowable upper limit value tb _MAX . Then, a battery temperature margin threshold value tb _LIM smaller than the battery temperature allowable upper limit value tb _MAX is set, and when the temperature of the lithium ion battery 11 is equal to or higher than the battery temperature margin threshold value tb _LIM , the motor 13 according to the driver's accelerator operation. Or the regenerative torque of the motor 13 corresponding to the driver's brake operation is reduced.
Thus, the temperature increase of the lithium ion battery 11 can be suppressed by reducing the power running torque or the regenerative torque. Therefore, even if an abnormality occurs in all systems of the friction brake, the charging permission condition regarding the battery temperature is satisfied and the regenerative operation is allowed, so that the backup performance by the regenerative brake can be ensured.

(10) The vehicle brake control device according to the present embodiment has a battery temperature margin threshold value obtained by reducing the battery temperature allowable upper limit value tb _MAX by the amount of increase in battery temperature when the motor 13 performs a predetermined regeneration. Set as Tm _tb .
In this way, in anticipation of the increase in battery temperature when regeneration is performed, even if an abnormality has occurred in all systems of the friction brake by giving a margin to the battery temperature allowable upper limit tb _MAX by that amount, Since predetermined sufficient regeneration is allowed, the back performance by the regenerative brake can be ensured.

(11) for a vehicle brake control device according to the present embodiment, the allowable charging conditions is that the temperature of the lithium ion battery 11 is greater than the battery temperature allowable lower limit tb _MIN. When the temperature of the lithium ion battery 11 is equal to or lower than the battery temperature allowable lower limit value tb _MIN , the power running torque of the motor 13 corresponding to the driver's accelerator operation is increased by Ta _tb . Further, the braking torque is increased by Ta _tb which is the increased power running torque of the motor 13.
Thus, the temperature increase of the lithium ion battery 11 can be accelerated | stimulated by increasing a power running torque and canceling that part by the increase in braking torque. Therefore, even if an abnormality occurs in all systems of the friction brake, the charging permission condition regarding the battery temperature is satisfied and the regenerative operation is allowed, so that the backup performance by the regenerative brake can be ensured.

(12) When the vehicle brake control device according to the present embodiment detects in advance that an abnormality occurs in all brake systems in the friction brake, the vehicle speed at which the maximum regenerative torque can be generated by the regeneration by the power generation operation of the motor 13. The vehicle speed is limited to the threshold value V _LIM .
As described above, since the vehicle speed V is lowered to the vehicle speed threshold V _LIM before an abnormality occurs in all the friction brake systems, even if an abnormality occurs in all the systems of the friction brake, at least according to the maximum regenerative torque. The regenerative brake can be operated, and sufficient braking performance can be ensured.

(13) The vehicle brake control device according to the present embodiment cancels the prohibition of charging of the lithium ion battery 11 from the motor 13 when detecting abnormality of all brake systems in the friction brake.
As described above, when an abnormality also occurs in the final friction brake system, the operation of the regenerative brake is permitted by releasing the restriction on the regenerative brake, so that the brake performance can be ensured.

(14) The vehicle brake control device according to the present embodiment controls the regenerative torque due to the power generation operation of the motor according to the driver's brake operation when detecting an abnormality of all brake systems in the friction brake.
Thus, when an abnormality occurs in the final friction brake system, the brake performance can be ensured by stopping the cooperative control of the regenerative brake and the friction brake and controlling the braking force with the regenerative brake alone. .

(15) The vehicle brake control device according to the present embodiment is more effective for the driver's brake operation when detecting abnormality of all brake systems in the friction brake than when detecting abnormality of all brake systems. Reduce the regenerative torque due to the power generation operation of the corresponding motor.
In this way, when an abnormality occurs in all systems of the friction brake, the braking torque corresponding to the driver's brake operation is reduced to ensure that the driver has an abnormality in the friction brake in the brake system. And prompt prompt repairs.

(16) In the vehicle brake control device according to the present embodiment, when the regenerative braking force by the power generation operation of the motor 13 is controlled, the vehicle deceleration estimated value Ge estimated to be generated by the regenerative braking force is When it is larger than the actually detected vehicle deceleration detection value Gd, the control of the regenerative braking force by the power generation operation of the motor 13 is stopped.
In this way, when the estimated deceleration value Ge is larger than the detected deceleration value Gd, by actually stopping the regenerative brake, for example, when it is not known whether the communication line is disconnected and the friction brake is operating, It is possible to prevent the friction brake from operating and double braking of the regenerative brake and the friction brake.

(17) The vehicle brake control method according to the present embodiment charges the motor 13 that drives the vehicle during powering operation by power from the lithium ion battery 11 and charges the lithium ion battery 11 by regeneration during power generation operation. Regeneration is allowed when the state of the system satisfies a predetermined charge permissible condition. And when the abnormality of some brake systems is detected among the friction brakes which consist of a several brake system, the state of a charge system is controlled so that charge permission conditions may be satisfy | filled.

As described above, when an abnormality in a part of the brake system in the friction brake is detected, the state of the charging system is controlled so as to satisfy the charging permission condition, so that regeneration due to the power generation operation of the motor is allowed. That is, since the backup performance by the regenerative brake can be ensured, the reliability of the backup performance can be improved.
Although the present invention has been described with reference to a limited number of embodiments, the scope of rights is not limited thereto, and modifications of the embodiments based on the above disclosure are obvious to those skilled in the art.

11 Lithium ion battery 12 Inverter 13 Motor 14 Reduction gear 15 Wheel 21 Brake pedal 22 Master cylinder 23 Wheel cylinder 24 Electric booster 25 Brake actuator 26 Stroke sensor 31 Battery controller 32 Brake controller 33 EV controller 34 Actuator controller 35 12V battery 36 DC / DC converter

Claims (16)

A friction brake comprising a plurality of brake systems;
A battery capable of charging and discharging power;
An electric motor that drives the vehicle with power from the battery during powering operation, charges the battery with regeneration during power generation operation, and the regeneration is allowed when the state of the charging system satisfies a predetermined charging permission condition;
An abnormality detecting means for detecting an abnormality of each brake system in the friction brake;
When the abnormality detecting means detects an abnormality of a part of the brake system in the friction brake , and the remaining brake system is in a normal and operable state, the state of the charging system is set so as to satisfy the charging permission condition. An abnormality detection state control means for controlling ,
The charge permission condition is that the charge amount of the battery is below a predetermined charge amount allowable upper limit value,
The abnormality detection state control means includes:
A charge amount margin threshold value smaller than the charge amount allowable upper limit value is set in advance, and when the charge amount of the battery is charged to the charge amount margin threshold value, charging to the battery from the electric motor is limited,
The vehicle brake control device according to claim 1, wherein when the abnormality detection unit detects an abnormality of all brake systems in the friction brake, the restriction on charging of the battery from the electric motor is released . A friction brake comprising a plurality of brake systems;
A battery capable of charging and discharging power;
An electric motor that drives the vehicle with power from the battery during powering operation, charges the battery with regeneration during power generation operation, and the regeneration is allowed when the state of the charging system satisfies a predetermined charging permission condition;
An abnormality detecting means for detecting an abnormality of the friction brake;
An abnormality detection state control means for controlling the state of the charging system so as to satisfy the charging permission condition when an abnormality of a part of the brake system in the friction brake is detected by the abnormality detection means ,
The charging permission condition is that the temperature of the battery exceeds a predetermined battery temperature allowable lower limit value,
The abnormality detection state control means includes:
When the temperature of the battery is equal to or lower than the allowable battery temperature lower limit value, the driving force by the power running operation of the electric motor according to the driver's accelerator operation is made larger than when the battery temperature exceeds the allowable battery temperature lower limit value. Thus, the vehicle brake control device increases the braking force of the vehicle by increasing the driving force by the power running operation of the electric motor while promoting the temperature rise of the battery . A friction brake comprising a plurality of brake systems;
A battery capable of charging and discharging power;
An electric motor that drives the vehicle with power from the battery during powering operation, charges the battery with regeneration during power generation operation, and the regeneration is allowed when the state of the charging system satisfies a predetermined charging permission condition;
An abnormality detecting means for detecting an abnormality of the friction brake;
An abnormality detection state control means for controlling the state of the charging system so as to satisfy the charging permission condition when the abnormality detecting means detects an abnormality of a part of the brake system in the friction brake;
An abnormality braking force control means for controlling the regenerative braking force by the power generation operation of the electric motor according to the brake operation of the driver when the abnormality detection means detects an abnormality of all brake systems in the friction brake;
The abnormal time braking force control means,
When the abnormality detection unit detects an abnormality in all the brake systems in the friction brake, the regeneration by the power generation operation of the electric motor according to the driver's brake operation is more effective than when no abnormality in all the brake systems is detected. A brake control device for a vehicle, wherein the braking force is reduced . A friction brake comprising a plurality of brake systems;
A battery capable of charging and discharging power;
An electric motor that drives the vehicle with power from the battery during powering operation, charges the battery with regeneration during power generation operation, and the regeneration is allowed when the state of the charging system satisfies a predetermined charging permission condition;
An abnormality detecting means for detecting an abnormality of the friction brake;
An abnormality detection state control means for controlling the state of the charging system so as to satisfy the charging permission condition when the abnormality detecting means detects an abnormality of a part of the brake system in the friction brake;
An abnormality braking force control means for controlling the regenerative braking force by the power generation operation of the electric motor according to the brake operation of the driver when the abnormality detection means detects an abnormality of all brake systems in the friction brake;
The abnormal time braking force control means,
When controlling the regenerative braking force by the power generation operation of the electric motor, when the estimated vehicle deceleration estimated to be generated by the regenerative braking force is larger than the actually detected vehicle deceleration detected value, A vehicular brake control device that stops control of regenerative braking force by power generation operation of the electric motor . The charge permission condition is that the charge amount of the battery is below a predetermined charge amount allowable upper limit value,
The abnormality detection state control means includes:
Preset a charge amount margin threshold smaller than the charge amount allowable upper limit,
As the state control of the charging system, when the charge amount of the battery is equal to or greater than the charge amount margin threshold value, the power running operation of the electric motor according to the driver's accelerator operation is performed than when the battery charge amount is less than the charge amount margin threshold value. by increasing the driving force by, along with promoting the discharge of the battery, any claim 1-4, characterized in that to increase the braking force of the amount corresponding to the vehicle with a larger driving force by the power running of the electric motor the vehicle brake control device according to an item or. Comprising electrical equipment that consumes the power of the battery;
The charge permission condition is that the charge amount of the battery is below a predetermined charge amount allowable upper limit value,
The abnormality detection state control means includes:
Preset a charge amount margin threshold smaller than the charge amount allowable upper limit,
As the state control of the charging system, when the amount of charge of the battery is equal to or greater than the charge amount margin threshold, by increasing the power consumption in the electrical equipment than when the charge amount margin threshold is below, The vehicle brake control device according to any one of claims 1 to 5, wherein discharge of the battery is promoted. The abnormality detection state control means includes:
From the charge amount allowable upper limit value, according to values only reduced charge amount when executing the predetermined regeneration by the electric motor to claim 5 or 6, characterized in that to set as the charge amount margin threshold Brake control device for vehicles. The battery enables charging from an external power source,
The abnormality detection state control means includes:
The vehicle brake control according to any one of claims 5 to 7 , wherein when the charge amount of the battery is equal to or greater than the charge amount margin threshold, charging of the battery from the external power source is prohibited. apparatus. The abnormality detection state control means includes:
The vehicle brake control device according to any one of claims 5 to 8 , wherein when the charge amount of the battery is equal to or greater than the charge amount margin threshold, charging of the battery from the electric motor is prohibited. . The charge permissible condition is that the temperature of the motor is below a predetermined motor temperature permissible upper limit value,
The abnormality detection state control means includes:
Preliminarily set a motor temperature margin threshold smaller than the motor temperature allowable upper limit,
As the state control of the charging system, when the temperature of the electric motor is equal to or higher than the electric motor temperature margin threshold, by the power running operation of the electric motor according to the accelerator operation of the driver than when the electric motor temperature is lower than the electric motor temperature margin threshold to reduce the driving force, or by decreasing the braking force by the power generating operation of the motor in accordance with the driver's brake operation, any one of claims 1-9, characterized in that to suppress the Atsushi Nobori of the motor The vehicle brake control device according to one item. The abnormality detection state control means includes:
11. The vehicle according to claim 10 , wherein a value obtained by reducing the motor temperature allowable upper limit value by an amount corresponding to an increase in motor temperature when a predetermined regeneration is executed by the motor is set as the motor temperature margin threshold. Brake control device. The charge permission condition is that the temperature of the battery is lower than a predetermined battery temperature allowable upper limit value,
The abnormality detection state control means includes:
Preset a battery temperature margin threshold smaller than the battery temperature allowable upper limit,
As the state control of the charging system, when the temperature of the battery is equal to or higher than the battery temperature margin threshold, it is based on the power running operation of the electric motor according to the driver's accelerator operation than when the battery temperature is lower than the battery temperature margin threshold. to reduce the driving force, or by decreasing the braking force by the power generating operation of the motor in accordance with the driver's brake operation, any one of claims 1 to 11, characterized in that to suppress the Atsushi Nobori of the battery The vehicle brake control device according to one item. The abnormality detection state control means includes:
13. The vehicle according to claim 12 , wherein a value obtained by reducing the battery temperature allowable upper limit value by an amount corresponding to an increase in battery temperature when a predetermined regeneration is performed by the electric motor is set as the battery temperature margin threshold value. Brake control device. Abnormality detection that restricts the vehicle speed to a vehicle speed at which maximum braking force can be generated by regeneration due to power generation operation of the motor when the abnormality detection means detects in advance that an abnormality occurs in all brake systems in the friction brake The vehicle brake control device according to any one of claims 1 to 13, further comprising an hourly vehicle speed control means. The abnormality detection state control means includes:
10. The vehicle brake control device according to claim 9 , wherein when the abnormality detection unit detects an abnormality of all brake systems in the friction brake, the prohibition of charging the battery from the electric motor is canceled. When the vehicle is driven by power from the battery during powering operation, and the electric motor that charges the battery by regeneration during power generation operation, when the charge amount of the battery is below a predetermined charge amount allowable upper limit value, Allow regeneration,
Of the friction brake comprising a plurality of brake system to detect the abnormality in part of the brake system, when the remaining brake system is operable state normally, the battery to be below the amount of charge allowable upper limit value Control the amount of charge
A charging amount margin threshold smaller than the allowable charging amount upper limit value is set in advance, and when the charging amount of the battery is charged to the charging amount margin threshold, charging of the battery from the electric motor is limited, and the friction brake The vehicle brake control method according to claim 1, wherein when the abnormality of all the brake systems is detected, restriction on charging of the battery from the electric motor is released.

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