KR20190065618A - Braking control method for eco-friendly vehicle - Google Patents

Abstract

The present invention relates to a braking control method for an eco-friendly vehicle, which can solve a braking force mismatch problem which may occur in a conversion process between regenerative braking and frictional braking performed at a low speed vehicle which is just before stopped when an eco-friendly vehicle is in braking. To this end, the braking control method of the present invention comprises the steps of: determining a target braking torque in accordance with a braking input value of a driver; determining a target hydraulic braking torque and a regenerative braking torque through a braking force distribution from the target braking torque; determining a target hydraulic pressure using a pressure-torque map from the determined target hydraulic braking torque; generating a braking torque with regenerative braking and hydraulic braking by controlling a braking hydraulic pressure of a brake device in accordance with the determined target hydraulic pressure while controlling a motor torque in accordance with the determined regenerative braking torque; determining a model hydraulic braking torque using the pressure-torque map from the target hydraulic pressure; determining a model braking torque from the model hydraulic braking torque and the regenerative braking torque, and determining model deceleration of a vehicle corresponding to the model braking torque; acquiring actual deceleration of the vehicle from a signal value of a longitudinal acceleration sensor; and correcting a map value of the pressure-torque map using a deceleration error which is a difference value between the actual deceleration and the model deceleration.

Description

[0001] The present invention relates to a braking control method for an eco-friendly vehicle,

The present invention relates to a braking control method for an environmentally friendly automobile, and more particularly, to a braking control method for an environmentally friendly automobile, which is capable of improving the braking force discrepancy that may occur during the transition between regenerative braking and frictional braking, To a braking control method for an automobile.

Eco-friendly cars are vehicles that have less or less pollutant emissions than internal combustion engine cars that use fossil fuels such as gasoline or diesel.

Recently, eco-friendly automobiles have been attracting attention due to energy depletion and environmental pollution. They have already been sold, commercialized, or are about to be commercialized.

Most of the eco-friendly vehicles have been developed in the form of a vehicle that travels by electric power, that is, a vehicle that travels by using the power of an electric motor.

Typical examples of such environmentally friendly vehicles include pure electric vehicles (EV), engines (internal combustion engines) and hybrid electric vehicles (HEV) that run on motors, And a fuel cell electric vehicle (FCEV) that operates by driving the motor with electric power generated in the fuel cell vehicle.

Among them, the hybrid vehicle means an engine that generates a driving force by burning fuel and a vehicle driven by a motor that generates a driving force by the electric energy of the battery, and a PHEV (Plug-in Hybrid Electric Vehicle), and general HEVs that are not.

There is also known a hybrid vehicle having a motor (drive motor) and a TMED (Transmission Mounted Electric Device) power train configuration with a transmission.

The TMED hybrid vehicle includes an engine and a motor serving as driving sources for driving the vehicle, an engine clutch interposed between the engine and the motor, an inverter for driving the motor, and a battery connected to the motor via an inverter, A transmission is mounted on the motor output side.

In addition, the hybrid vehicle includes a hybrid starter and generator (HSG) connected to the engine so as to be able to transmit power, for starting the engine or performing power generation by the rotational force transmitted from the engine.

Among the above constructions, the engine clutch connects or disconnects the engine and the motor so as to transmit power, and the inverter converts the direct current of the battery into a three-phase alternating current for driving the motor and the HSG, and applies the three-

The hybrid vehicle having such a configuration can be driven in an EV (Electric Vehicle) mode, which is a pure electric vehicle mode using only the power of the motor, and a HEV (Hybrid Electric Vehicle) mode, in which the power of the engine and the power of the motor are used in combination.

In an environmentally friendly vehicle such as an electric vehicle (EV) or a fuel cell vehicle (FCEV) using a motor as a vehicle driving source including a hybrid vehicle (HEV, PHEV), a regeneration mode for charging the battery using a motor as a generator can be performed .

That is, a regenerative mode is performed in which the kinetic energy of the vehicle is converted into electric energy upon coasting of the vehicle during braking or inertia, and in the regenerative mode, the motor receiving the kinetic energy of the vehicle operates as a generator, To charge the battery.

In such an environment-friendly automobile, energy can be recovered by the motor, so that fuel efficiency of the vehicle can be improved.

In order to implement the regenerative braking system of the environmentally friendly automobile, regenerative braking coordination control is performed so that the sum of the regenerative braking force generated by the motor during regenerative braking and the frictional braking force generated by the braking device matches the total braking force required by the driver Technology is needed.

Here, the regenerative braking force is generated when the kinetic energy of the vehicle is converted into electric energy by the power generation operation of the motor, and is transmitted to the wheel, so that it can be called the electric braking force.

A conventional brake device in a vehicle is a frictional braking device or a hydraulic braking device because the caliper is operated by the hydraulic pressure and the friction pad presses the disc mounted on the wheel to generate the braking force on the wheel. And the braking torque may be referred to as a friction braking force, a friction braking torque, a hydraulic braking force and a hydraulic braking torque.

A so-called blending section appears in which the regenerative braking force is decreased and the frictional braking force is increased in the regenerative braking cooperation control process until the driver stops the vehicle by stopping the brake pedal.

If the driver depresses a certain amount of brake pedal, the regenerative braking force should be reduced at a certain moment during vehicle deceleration and the frictional braking force should be increased accordingly. At this time, the sum of regenerative braking force and frictional braking force must satisfy a certain total braking force required by the driver.

That is, even if the regenerative braking force and the frictional braking force change, the total braking force to be transmitted to the vehicle wheel should be kept constant, and the deceleration of the vehicle should also be maintained at a certain level.

According to the related art, a large frictional braking force is suddenly generated due to the frictional coefficient of the friction pad of the braking device in the blending section, so that the braking force (the sum of the regenerative braking force and the frictional braking force) May occur.

On the other hand, in an eco-friendly vehicle that can regenerate a regenerative braking vehicle, that is, a regenerative braking vehicle equipped with a motor, the frictional braking and the regenerative braking So that the deceleration of the vehicle may instantaneously increase in the blending period.

The braking force change during the blending interval increases while the friction braking force is increased, so that the driver can feel the braking feeling according to the braking force change.

This braking disturbance occurs in the region where the frictional braking force decreases or the frictional braking force increases rather than the small section.

In particular, when the driver stops the vehicle by stepping on the brake pedal, a large deceleration change occurs immediately before the stop, and the driver may feel uncomfortable due to such a change in deceleration, that is, a jerk.

Therefore, it is necessary to improve the problem of the braking force discrepancy occurring in the process of switching between the frictional braking and the regenerative braking which are performed at a low vehicle speed immediately before stopping the braking of the environmentally friendly vehicle.

Regenerative braking is performed through the motor, which is a torque generating device, at the time of braking the eco-friendly automobile. The decelerating vehicle rapidly reduces the regenerative braking force and stops the braking force before the stopping, thereby converting the source of braking force from the motor to the friction braking device.

At this time, ideally, the braking force generated by regenerative braking should be controlled to smoothly switch to the same level of frictional braking force, but it is difficult to secure a constant frictional braking force by various environmental variables.

Therefore, even though the driver's brake pedal input is kept constant, the braking force changes instantaneously, and unpleasant vehicle deceleration changes frequently.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide an eco-friendly vehicle which can improve the problem of the braking force discrepancy that may occur in the process of switching between regenerative braking and frictional braking, The present invention provides a method of controlling a braking of an automobile.

According to an embodiment of the present invention, a target braking torque is determined according to a braking input value of a driver. Determining a target hydraulic braking torque and a regenerative braking torque from a target braking torque through braking force distribution; Determining a target hydraulic pressure using the pressure-torque map from the determined target hydraulic braking torque; Controlling the motor torque according to the determined regenerative braking torque and controlling the braking oil pressure of the braking device according to the determined target oil pressure to generate a braking torque by regenerative braking and hydraulic braking; Determining a model hydraulic braking torque using the pressure-torque map from the target hydraulic pressure; Determining a model braking torque from the model hydraulic braking torque and the regenerative braking torque and determining a model deceleration of the vehicle corresponding to the model braking torque; Obtaining the actual deceleration of the vehicle from the signal value of the closing rate sensor; And correcting a map value of the pressure-torque map using a deceleration error that is a difference between the actual deceleration and the model deceleration.

Thus, according to the braking control method of an eco-friendly automobile according to the present invention, it is possible to improve the problem of braking force discrepancy caused in the process of switching between regenerative braking and frictional braking during braking through adaptive control using an acceleration sensor, Changes and shocks, braking unevenness, and drop in operability at the time of deceleration can be solved.

1 is a flowchart showing a braking control process of an environmentally friendly automobile according to the present invention.
2 is a flow chart showing the friction braking hydraulic compensation logic of the braking control process according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

The present invention relates to a braking control method of an eco-friendly automobile, which can improve the problem of braking force discrepancy that may occur in the process of switching between regenerative braking and frictional braking performed at a low vehicle speed just before stopping an eco-friendly automobile.

In the present invention, an adaptive control using an acceleration / deceleration sensor is proposed to prevent an unpleasant feeling of change in deceleration, shock generation, braking unevenness, and deterioration in operability during deceleration.

As a conventional technique for solving the above-mentioned problems and securing braking linearity, Korean Patent Laid-Open Publication No. 10-2016-0051320 (May 2016.11) corrects the friction braking force based on the environmental information acquired through the temperature sensor and the humidity sensor Is disclosed.

However, such a method has limitations that can not be flexibly applied to changes in the friction surface, changes in the size and thickness of the water particles, and even if there is a frictional force model for sophisticated temperature and humidity, there is a problem.

Accordingly, in the present invention, adaptive control is applied to correct and update the map value for friction braking control through learning by applying feedback correction so that the characteristics of the control system can be changed in accordance with environmental changes, Braking sensation and driver's sense of deceleration.

Particularly, in the present invention, the feedback on the environmental variable is performed by using an acceleration / deceleration sensor, and the torque value in the map for friction braking is updated and corrected in real time, so that the conversion process between the regenerative braking and the frictional braking is consistent with the vehicle deceleration The undesirable unpleasant deceleration can be achieved without change.

1 is a flowchart showing a braking control process of an environmentally friendly automobile according to the present invention.

As shown in the figure, the braking control process of the eco-friendly vehicle according to the present invention can be performed by controlling the in-vehicle controllers in a coordinated manner.

The eco-friendly vehicle is equipped with a controller (Hybrid Control Unit, HCU / Vehicle Control Unit (VCU)) 10 as a top controller for controlling the overall operation of the vehicle, and various controllers for controlling various devices of the vehicle.

A brake controller (BCU) 20 for controlling the operation of the braking device (friction braking device, hydraulic braking device), a motor controller (Motor A control unit (MCU) 30 for controlling the operation of the transmission, a transmission control unit (TCU) 50 for controlling the operation of the transmission, battery state information collected and used for battery charge and discharge control, A battery management system (BMS) 40 for performing control for controlling the battery 40, and the like.

The HCU 10 and each of the controllers communicate with each other through CAN communication to perform cooperative control. The host controller receives the various information from the lower controllers and collects the control commands to the lower controller .

The braking control according to the present invention can be started when the driver steps on the brake pedal 1. [

When the driver depresses the brake pedal 1, the brake controller (BCU) 20 determines the total braking amount required in the vehicle according to the braking input value of the driver (S11) and determines the regenerative braking allowable amount through the braking force distribution To the vehicle controller (S12, S13).

Here, the braking input value of the driver may be a value according to the operating state of the brake pedal of the driver, and more specifically, it may be a brake pedal stroke, which is a signal value of BPS (Bake Pedal stroke Sensor).

The HCU 10 determines the regenerative braking possible amount in accordance with the vehicle condition on the basis of the received regenerative braking allowable amount and then calculates the maximum regenerative braking amount from the regenerative braking allowable amount by the battery controller BMS 40, (Battery chargeable power) and the maximum charge torque (motor chargeable torque) received by the motor controller (MCU) 30 (S15), and a motor torque command is determined from the regenerative braking torque To the motor controller (S16).

The motor controller 30 controls the motor torque through the inverter in accordance with the motor torque command received from the vehicle controller 10 (S17), thereby causing regenerative braking.

The braking control is performed by the brake controller 20. The braking control is performed by the vehicle controller 10 based on the shift state information received from the shift controller 50 from the regenerative braking torque, (S19, S20, S21, S22).

Further, when the regenerative braking execution amount is determined, the vehicle controller 10 transmits the regenerative braking execution amount to the brake controller 20, and the braking force distribution using the regenerative braking execution amount received from the vehicle controller 10 in the brake controller 20 (S23, S24).

At this time, the brake controller 20 determines the friction brake amount (hydraulic brake brake amount) by subtracting the regenerative brake execution amount received from the vehicle controller 10 from the total brake amount in step S11 (S24).

The brake controller 20 controls the operation of the friction braking device so as to generate a braking force corresponding to the finally determined frictional braking amount, whereby the friction braking is performed (S25).

As a result, the braking and deceleration of the vehicle, which satisfies the total braking force required by the driver (that is, the total braking amount in the step S11) by the regenerative braking force by the motor and the frictional braking force by the frictional braking device, is performed (S26).

In this manner, the plurality of controllers are cooperatively controlled to perform vehicle braking and deceleration. In the coordination control process described above, the total braking amount, the regenerative braking allowable amount, the regenerative braking allowable amount, and the regenerative braking execution amount may be torque values.

In the present invention, the brake controller 20 may be an Active Hydraulic Booster (AHB).

Meanwhile, in the present invention, logic (S27, S31, S32, S33) for compensating the frictional braking hydraulic pressure is added in the cooperative control process of the controllers for braking the vehicle, that is, in the cooperative control process described above.

That is, the total braking amount is determined according to the driver braking input value (that is, the brake pedal stroke, which is the signal value of the BPS) in step S11 of the above-described cooperative control process. After the regenerative braking torque is determined in step S15, To cancel the error of the model deceleration rate by using the deceleration (actual vehicle deceleration) measured and obtained from the signal value of the closing speed sensor 2 as the feedback value when the vehicle braking and deceleration is performed in step S26 Friction brake hydraulic compensation logic is added.

1, steps S27, S31, S32, and S33 represent such frictional braking hydraulic pressure compensating logic. FIG. 2 is a flowchart showing the frictional braking hydraulic compensation logic of the braking control process according to the present invention. The compensation logic will now be described.

The total braking amount (target braking torque) in accordance with the driver braking input value is determined by the brake controller (BCU) 20 during the entire cooperative control process of Fig. 1, and is transmitted to the vehicle controller (HCU) The regenerative braking torque is determined (S15).

Further, the brake controller 20 determines the frictional braking amount (the target hydraulic braking torque and the target frictional braking torque) obtained by subtracting the regenerative braking execution amount from the total braking amount in step S24.

When the frictional brake amount, that is, the target hydraulic braking torque, is determined as described above, the brake controller 20 uses the map (pressure-torque map) to calculate the braking device (friction braking device, hydraulic braking device) from the determined target hydraulic braking torque, (Step S25-1).

Then, the brake controller 20 controls the braking hydraulic pressure of the braking device to the determined target hydraulic pressure (S25 (braking torque)) to generate the hydraulic braking torque (friction braking torque) -2) so that the hydraulic braking torque corresponding to the target hydraulic pressure is generated by the brake device (S25-3).

At the same time, the vehicle controller 10 determines a motor torque command from the regenerative braking torque determined in step S15 and outputs it to the motor controller (MCU) 30 (S16). The motor controller 30 receives (Regenerative braking torque) through the inverter in accordance with the motor torque command to regenerate braking (S17, S18).

As a result, the total braking amount (total braking torque) required by the driver can be satisfied by the sum of the hydraulic braking torque by the braking device and the regenerative braking torque by the motor, and the sum of the hydraulic braking torque and the regenerative braking torque The vehicle is decelerated at a deceleration corresponding to the braking torque (S26).

Further, the present invention corrects and updates the map value for the friction braking control by learning so that the frictional braking hydraulic pressure compensation can be performed using the actual vehicle deceleration information measured and acquired through the acceleration / deceleration sensor 2 as feedback information .

At this time, feedback control is performed to cancel the error between the modeled deceleration and the actual vehicle deceleration measured through the acceleration sensor 2 as described later.

In the present invention, when the actual vehicle deceleration is greater than the modeled deceleration, the hydraulic pressure for the friction braking is learned downward, and when the actual vehicle deceleration is lower than the modeled deceleration, the hydraulic pressure for the friction braking is learned upward.

That is, when the brake controller 20 corrects the map value by a value corresponding to the deceleration error in the pressure-torque map, and when the actual vehicle deceleration is larger than the modeled deceleration, in order to cancel the deceleration error, In the pressure-torque map, the hydraulic value (map value) corresponding to the target hydraulic braking torque is reduced by the pressure value corresponding to the deceleration error.

Alternatively, the brake controller 20 may be provided to increase the torque value (map value) corresponding to the target oil pressure in the pressure-torque map by a torque value corresponding to the deceleration error.

On the contrary, when the actual vehicle deceleration is smaller than the modeled deceleration, the brake controller 20 sets the hydraulic pressure value (map value) corresponding to the target hydraulic braking torque in the pressure-torque map to the deceleration The deceleration is increased by the pressure value corresponding to the error.

Alternatively, the brake controller 20 may be provided to reduce the torque value (map value) corresponding to the target oil pressure in the pressure-torque map by a torque value corresponding to the deceleration error.

It has been described that the hydraulic pressure value corresponding to the specific hydraulic pressure value, that is, the hydraulic pressure value corresponding to the target hydraulic pressure braking torque, or the specific torque value, that is, the torque value corresponding to the target hydraulic pressure, can be corrected by an amount corresponding to the deceleration error from above , It is also possible to collectively correct the oil pressure value or the torque value in the entire region of the map by an amount corresponding to the deceleration error in the present invention.

At this time, a scale factor or a gain value is determined and adjusted to a value corresponding to a deceleration error, and the determined scale factor or gain value is applied to a previous oil pressure value or a torque value in the map, Or a method of correcting the torque value can be applied.

In order to carry out this process, the brake controller 20 receives a signal of an acceleration / deceleration sensor 2 installed in the vehicle and acquires vehicle deceleration information generated in the actual vehicle during braking from the signal value of the acceleration / (S27).

In the following description, the actual vehicle deceleration acquired through the acceleration / deceleration sensor 2 will be referred to as "actual deceleration", and the modeled deceleration will be abbreviated as "model deceleration".

In the present invention, it is preferable to set a condition for learning using the error between the actual deceleration and the deceleration of the model. The brake controller 20 only detects the actual measured and acquired through the acceleration sensor 2 when the set learning condition is satisfied And performs learning control for correcting and updating map values using deceleration information as feedback information.

Here, the learning conditions include a condition that the actual deceleration of the vehicle acquired through the acceleration sensor is within a predetermined suitable range, a condition that the vehicle speed is within a predetermined range, a condition where the braking input value of the driver is constant, a road gradient A condition in which the noise component of the signal value (measurement value) of the acceleration / deceleration sensor and the signal value (measurement value) of the acceleration / deceleration sensor is within a predetermined range, and a condition And the learning can be set to be performed only when all of these conditions are satisfied.

On the other hand, in order to follow the target braking torque (i.e., the total demanded driver's braking amount determined in step S11) of the hydraulic braking torque by the braking device at the time of vehicle braking and the regenerative braking torque by the motor, the hydraulic braking torque (The hydraulic braking force) must follow the target hydraulic braking torque determined by the brake controller 20 (i.e., the frictional braking torque determined in step S24), and the regenerative braking torque generated by the motor is controlled by the target regenerative brake (I.e., the regenerative braking torque determined in step S15).

In the case of the regenerative braking torque generated by the motor in general, the motor can be relatively accurately controlled, so that it is possible to accurately follow the target regenerative braking torque.

In the case of the motor control, since it is an electric control, it is possible to perform accurate control, and the torque control followability with respect to the target value is good, and control to follow the target regenerative braking torque accurately is possible.

However, in the case of brake control, precise and precise control in the hydraulic control process through the valve control and the like is difficult to achieve, and the followability to the target value is poor due to the hydraulic transient state characteristic.

In addition, even if accurate control is performed, there are many variables in the portion generating the actual braking force. The friction characteristics such as friction coefficient between the friction pad and the disc may be changed due to environmental conditions such as temperature and humidity, Even if controlled properly, the friction braking force generated from the actual wheel may vary.

As described above, in the case of the hydraulic braking torque (hydraulic braking force) generated by the braking device, it is difficult to follow the target hydraulic braking torque (the target frictional braking torque) due to the uncertainty of the frictional characteristic such as the friction coefficient of the friction pad.

This is a major cause of the driver feeling a sense of damping and deceleration even though the driver is pressing the brake pedal constantly.

Therefore, in the present invention, when the brake controller 20 determines the target hydraulic pressure using the map (pressure-torque map) from the target hydraulic braking torque in step S25-1, the map (pressure-torque map) Is used to determine the model hydraulic braking torque (S28).

In the present invention, the pressure-torque map of step S25-1 for determining the target hydraulic pressure from the target hydraulic braking torque and the pressure-torque map of step S28 for determining the model hydraulic braking torque from the target hydraulic pressure, It can be the same map with the same correlation.

The model hydraulic braking torque obtained based on the map as described above may be different from the actually generated hydraulic braking torque even if the braking device is controlled to the target hydraulic pressure.

When the model hydraulic braking torque is determined as described above, the brake controller 20 determines the model braking torque by summing it with the regenerative braking torque as described above (S29). The model deceleration rate (S30).

Here, in converting the model braking torque into the model deceleration, setting data that defines a correlation between the model braking torque and the model deceleration may be used. Such setting data may be expressed by a formula that can calculate the model deceleration from the model braking torque Or may be a map or a table in which the model deceleration is set to a value according to the model braking torque.

Further, the brake controller 20 calculates an error which is a difference value between the actual deceleration and the model deceleration, and filters the error to obtain the final deceleration error (S31-1, S31-2).

The deceleration measured by the vehicle's closing speed sensor 2 includes not only the pure deceleration component of the vehicle but also the vibration component due to the suspension and road surface characteristics.

Accordingly, in order to extract only the pure deceleration component of the vehicle, the error between the actual deceleration and the model deceleration may be calculated, and then the error may be corrected using the filtering or the vehicle speed.

In the present invention, since the braking force correction is aimed at, it is the main purpose of the filter to extract only the deceleration deviation portion due to the braking force error.

However, additional factors that may cause deceleration variation include suspension (suspension) pitching, road surface inclination, vehicle equivalent inertia (weight) change, air volume change, etc., It is ideal to extract only the deceleration part of the deceleration due to the above-mentioned problems. However, if these parts are modeled separately, the complexity of the control logic increases and the robustness degrades.

Therefore, only the most important part of the road surface inclination angle can be corrected as required, or only a simple low-pass filter is applied to slowly take an average error over several braking guns, and a long-term correction .

When the deceleration error is obtained as described above, the brake controller 20 corrects and updates the map value of the pressure-torque map by a value corresponding to the deceleration error so that the deceleration error at the time of control can be canceled.

At this time, the brake controller 20 converts the deceleration error into a corresponding torque value (S32), and corrects the torque value that is the map value of the pressure-torque map by the torque value corresponding to the deceleration error. (The target hydraulic braking torque) is increased or decreased by a torque value corresponding to the deceleration error.

Or the brake controller 20 may be set to convert the deceleration error into a corresponding pressure value and to correct the hydraulic pressure value of the pressure-torque map by a pressure value corresponding to the deceleration error, (The target hydraulic pressure) is increased or decreased by a pressure value corresponding to the deceleration error.

The correction is performed simultaneously for both the pressure-torque map of step 25-1 and the pressure-torque map of step S28, and then the corrected map is used in steps 25-1 and step S28, The actual hydraulic braking torque becomes equal to the model hydraulic braking torque when the hydraulic braking torque is generated again.

In step S32, setting data that defines a correlation between the deceleration error and the torque value may be used in converting the deceleration error into the torque value. The setting data may be a value corresponding to the deceleration error It can be a map or a table.

The setting data may be a torque value set according to the deceleration error based on the data obtained in the preceding test and evaluation process, and may be input to and stored in the brake controller 20 and used.

Or a formula that can calculate the torque value using the deceleration error.

When the brake controller 20 corrects the oil pressure value of the pressure-torque map by the pressure value by converting the deceleration error into the pressure value, the value corresponding to the deceleration error so that the deceleration error can be converted into the pressure value Setting data such as a map or a table in which the pressure value is set can be used.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. And are also included in the scope of the present invention.

1: Brake pedal
2: Acceleration sensor
10: vehicle controller
20: Brake controller
30: Motor controller
40: Battery controller
50:

Claims (10)

Determining a target braking torque according to a braking input value of a driver;
Determining a target hydraulic braking torque and a regenerative braking torque from a target braking torque through braking force distribution;
Determining a target hydraulic pressure using the pressure-torque map from the determined target hydraulic braking torque;
Controlling the motor torque according to the determined regenerative braking torque and controlling the braking oil pressure of the braking device according to the determined target oil pressure to generate a braking torque by regenerative braking and hydraulic braking;
Determining a model hydraulic braking torque using the pressure-torque map from the target hydraulic pressure;
Determining a model braking torque from the model hydraulic braking torque and the regenerative braking torque and determining a model deceleration of the vehicle corresponding to the model braking torque;
Obtaining the actual deceleration of the vehicle from the signal value of the closing rate sensor; And
And correcting the map value of the pressure-torque map using a deceleration error that is a difference between the actual deceleration and the model deceleration.
The method according to claim 1,
A condition that the actual deceleration of the vehicle is within a predetermined range,
A condition in which the vehicle speed is within a predetermined range,
If the driver's braking input value is constant,
A condition that the road gradient is within a predetermined range, and
When the condition that the noise component of the signal value of the closing rate sensor and the wheel speed sensor is equal to or less than a predetermined value is satisfied,
Wherein the step of correcting the map value of the pressure-torque map is performed using the deceleration error.
The method according to claim 1,
Wherein the model braking torque is obtained by summing the model hydraulic braking torque and the regenerative braking torque.
The method according to claim 1,
Wherein the step of correcting the map value of the pressure-torque map using the deceleration error comprises:
Determining a torque value corresponding to the deceleration error; And
And increasing or decreasing a torque value, which is a map value corresponding to the target oil pressure, in the pressure-torque map by a torque value corresponding to the deceleration error.
The method of claim 4,
When the actual deceleration is larger than the model deceleration by comparing the actual deceleration and the model deceleration, the torque value as the map value is increased by a torque value corresponding to the deceleration error, and when the actual deceleration is smaller than the model deceleration And decreasing the torque value as the map value by a torque value corresponding to the deceleration error.
The method of claim 4,
Wherein setting data in which a torque value is set to a value according to a deceleration error is used in a process of determining a torque value corresponding to the deceleration error.
The method according to claim 1,
Wherein the step of correcting the map value of the pressure-torque map using the deceleration error comprises:
Determining a pressure value corresponding to the deceleration error; And
And increasing or decreasing an oil pressure value corresponding to the target hydraulic braking torque by the pressure value corresponding to the deceleration error in the pressure-torque map.
The method of claim 7,
If the actual deceleration is larger than the model deceleration, comparing the actual deceleration and the model deceleration to reduce the hydraulic pressure value by a pressure value corresponding to the deceleration error, and when the actual deceleration is smaller than the model deceleration, Value is increased by a pressure value corresponding to the deceleration error.
The method of claim 7,
Wherein the setting data in which the pressure value is set to a value corresponding to the deceleration error is used in the process of determining the pressure value corresponding to the deceleration error.
The method according to claim 1,
Wherein the step of correcting the map value of the pressure-torque map using the deceleration error comprises:
Determining a scale factor or gain corresponding to the deceleration error so that an oil pressure value or a torque value of the entire region in the pressure-torque map can be corrected by a scale factor or a gain; And
And applying the determined scale factor or gain value to an oil pressure value or a torque value, which is a previous map value, so as to correct by the determined scale factor or gain value.

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