CN112455408A - Control method, device, equipment and medium of brake system - Google Patents

Control method, device, equipment and medium of brake system Download PDF

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Publication number
CN112455408A
CN112455408A CN202110144649.0A CN202110144649A CN112455408A CN 112455408 A CN112455408 A CN 112455408A CN 202110144649 A CN202110144649 A CN 202110144649A CN 112455408 A CN112455408 A CN 112455408A
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China
Prior art keywords
air pressure
pressure
difference
pressure difference
time
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CN202110144649.0A
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Chinese (zh)
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CN112455408B (en
Inventor
徐显杰
赵永涛
王翔宇
李亮
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Tianjin Soterea Automotive Technology Co Ltd
Zhejiang Suoto Ruian Technology Group Co Ltd
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Tianjin Soterea Automotive Technology Co Ltd
Zhejiang Suoto Ruian Technology Group Co Ltd
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Publication of CN112455408A publication Critical patent/CN112455408A/en
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/66—Electrical control in fluid-pressure brake systems
    • B60T13/68—Electrical control in fluid-pressure brake systems by electrically-controlled valves
    • B60T13/683—Electrical control in fluid-pressure brake systems by electrically-controlled valves in pneumatic systems or parts thereof

Abstract

The invention discloses a control method, a control device, equipment and a control medium of a brake system. The control method of the brake system includes: receiving actual measurement air pressure and target air pressure, wherein the actual measurement air pressure is the current brake cavity air pressure detected by a pressure sensor, and the target air pressure is the expected brake cavity air pressure; calculating the air pressure difference between the target air pressure and the measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference; if the absolute value of the air pressure difference is greater than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressurization time or the depressurization time according to the actually measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram, and if the absolute value of the air pressure difference is less than the preset air pressure difference, determining the pressurization time or the depressurization time by adopting a proportional-integral-derivative control method; the measured air pressure is controlled to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, and the feedback control of the air pressure of the brake cavity is realized. The technical scheme provided by the embodiment of the invention improves the dynamic response speed of the braking system.

Description

Control method, device, equipment and medium of brake system
Technical Field
The embodiment of the invention relates to the technical field of braking, in particular to a control method, a control device, control equipment and a control medium of a braking system.
Background
In a by-wire pneumatic brake system for a vehicle, the air pressure of a brake chamber is generally feedback controlled in a closed loop according to air pressure data collected by a pressure sensor, which is generally disposed in a load chamber of a relay valve communicating with the brake chamber.
In the prior art, an electronic control unit receives load cavity air pressure acquired by a pressure sensor, a pressurization time or a decompression time is obtained in a calculation mode according to the load cavity air pressure, the load cavity air pressure changes after the pressure is increased according to the pressurization time or the pressure is reduced according to the decompression time, the pressure sensor acquires the load cavity air pressure again, and the operation is repeated until the load cavity air pressure is equal to a target air pressure determined according to user braking operation. The control method has the advantages that the number of feedback cycles is large, the calculated amount is large, and the dynamic response speed of the brake system is slow.
Disclosure of Invention
The invention provides a control method, a control device, control equipment and a control medium of a braking system, which are used for improving the dynamic response speed of the braking system on the premise of ensuring good controllability of air pressure regulation, small regulation error and strong system adaptability.
In a first aspect, an embodiment of the present invention provides a control method for a brake system, including:
receiving actual measurement air pressure and target air pressure, wherein the actual measurement air pressure is the current brake cavity air pressure detected by a pressure sensor, and the target air pressure is the expected brake cavity air pressure;
calculating the air pressure difference between the target air pressure and the measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference;
if the absolute value of the air pressure difference is larger than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressurization time or the depressurization time according to the actually measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram; if the absolute value of the air pressure difference is smaller than the preset pressure difference, determining the pressurization time or the decompression time by adopting a proportional-integral-derivative control method; controlling the actually measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, and realizing feedback control of the air pressure of the brake cavity;
the pressure increasing and reducing characteristic diagram comprises a plurality of pressure increasing characteristic curves and a plurality of pressure reducing characteristic curves, the pressure increasing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressure increasing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
In a second aspect, an embodiment of the present invention further provides a control device for a brake system, including:
the air pressure receiving module is used for receiving measured air pressure and target air pressure, wherein the measured air pressure is the current brake cavity air pressure detected by the pressure sensor, and the target air pressure is the expected brake cavity air pressure;
the air pressure difference calculating module is used for calculating the air pressure difference between the target air pressure and the measured air pressure and comparing the absolute value of the air pressure difference with a preset pressure difference;
the first time determination module is used for determining the pressurization time or the depressurization time according to the measured air pressure, the air pressure difference and the pressure increasing and reducing characteristic diagram when the absolute value of the air pressure difference is larger than the preset air pressure and the air pressure difference is within the pressure difference range of the pressure increasing and reducing characteristic diagram, and determining the pressurization time or the depressurization time by adopting a proportional-integral-derivative control method when the absolute value of the air pressure difference is smaller than the preset pressure difference so as to control the measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, thereby realizing the feedback control of the air pressure of the brake cavity;
the pressure increasing and reducing characteristic diagram comprises a plurality of pressure increasing characteristic curves and a plurality of pressure reducing characteristic curves, the pressure increasing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressure increasing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
In a third aspect, an embodiment of the present invention further provides an apparatus, where the apparatus includes:
one or more processors;
a storage device for storing one or more programs,
when the one or more programs are executed by the one or more processors, the one or more processors are caused to implement the control method of the brake system as described in the above first aspect.
In a fourth aspect, the embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored, which when executed by a processor, implements the control method of the brake system according to the first aspect.
The technical scheme provided by the embodiment of the invention comprises the steps of receiving actual measurement air pressure and target air pressure, wherein the actual measurement air pressure is the current brake cavity air pressure detected by a pressure sensor, the target air pressure is the brake cavity air pressure expected to be reached, calculating the air pressure difference between the target air pressure and the actual measurement air pressure, comparing the absolute value of the air pressure difference with a preset pressure difference, determining the pressurization time or the depressurization time according to the actual measurement air pressure, the air pressure difference and an increasing and decreasing characteristic diagram if the absolute value of the air pressure difference is larger than the preset pressure difference and is positioned in the pressure difference range of the increasing and decreasing characteristic diagram, determining the pressurization time or the depressurization time by adopting a proportional integral differential control method to control the actual measurement air pressure to gradually approach the target air pressure until the brake cavity air pressure reaches the target air pressure, realizing the feedback control of the brake cavity air pressure, and enabling the actual measurement air pressure to be larger than the target, the brake system can realize the control of the air pressure of the brake cavity by a convenient table look-up control method, does not need a complex calculation process, controls the quick approach of the measured air pressure to the target air pressure, when the difference between the actual measurement air pressure and the target air pressure is small, the proportional-integral-derivative control method is used for realizing the control of the air pressure of the brake cavity, the actual measurement air pressure is ensured to gradually approach the target air pressure in a small step length, the controllability of the air pressure regulation is good, the error between the regulated air pressure of the brake cavity and the target air pressure is small, and the advantage of adaptive adjustment corresponding to different system parameters based on the integral differential control method enhances the system adaptability of air pressure control, even if the air inlet valve or the exhaust valve with different parameters is replaced, good air pressure control can be still realized, and therefore the dynamic response speed of the braking system is improved on the premise that good air pressure regulation controllability, small regulation error and strong system adaptability are guaranteed.
Drawings
Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments made with reference to the following drawings:
fig. 1 is a schematic flow chart of a control method of a brake system according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a braking system provided by an embodiment of the present invention;
FIG. 3 is a graph of pressure increase and decrease characteristics provided by an embodiment of the present invention;
FIG. 4 is a schematic flow chart illustrating a method for controlling a brake system according to an embodiment of the present invention;
FIG. 5 is a schematic flow chart illustrating a method for controlling a brake system according to an embodiment of the present invention;
FIG. 6 is a schematic flow chart illustrating a method for controlling a brake system according to an embodiment of the present invention;
FIG. 7 is a schematic flow chart illustrating a method for controlling a brake system according to an embodiment of the present invention;
FIG. 8 is a schematic flow chart illustrating a method for controlling a brake system according to an embodiment of the present invention;
fig. 9 is a schematic structural diagram of a control device of a brake system according to an embodiment of the present invention;
fig. 10 is a schematic structural diagram of an apparatus according to an embodiment of the present invention.
Detailed Description
To further illustrate the technical means and effects of the present invention adopted to achieve the predetermined objects, the following detailed description will be given of the embodiments, structures, features and effects of a control method, a control device, a control apparatus, a control device, and a control medium of a brake system according to the present invention with reference to the accompanying drawings and preferred embodiments.
The embodiment of the invention provides a control method of a braking system, which comprises the following steps:
receiving actual measurement air pressure and target air pressure, wherein the actual measurement air pressure is the current brake cavity air pressure detected by a pressure sensor, and the target air pressure is the expected brake cavity air pressure;
calculating the air pressure difference between the target air pressure and the measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference;
if the absolute value of the air pressure difference is larger than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressurization time or the depressurization time according to the actually measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram; if the absolute value of the air pressure difference is smaller than the preset pressure difference, determining the pressurization time or the decompression time by adopting a proportional-integral-derivative control method; controlling the actually measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, and realizing feedback control of the air pressure of the brake cavity;
the pressure increasing and reducing characteristic diagram comprises a plurality of pressure increasing characteristic curves and a plurality of pressure reducing characteristic curves, the pressure increasing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressure increasing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
The technical scheme provided by the embodiment of the invention comprises the steps of receiving actual measurement air pressure and target air pressure, wherein the actual measurement air pressure is the current brake cavity air pressure detected by a pressure sensor, the target air pressure is the brake cavity air pressure expected to be reached, calculating the air pressure difference between the target air pressure and the actual measurement air pressure, comparing the absolute value of the air pressure difference with a preset pressure difference, determining the pressurization time or the depressurization time according to the actual measurement air pressure, the air pressure difference and an increasing and decreasing characteristic diagram if the absolute value of the air pressure difference is larger than the preset pressure difference and is positioned in the pressure difference range of the increasing and decreasing characteristic diagram, determining the pressurization time or the depressurization time by adopting a proportional integral differential control method to control the actual measurement air pressure to gradually approach the target air pressure until the brake cavity air pressure reaches the target air pressure, realizing the feedback control of the brake cavity air pressure, and enabling the actual measurement air pressure to be larger than the target, the brake system can realize the control of the air pressure of the brake cavity by a convenient table look-up control method, does not need a complex calculation process, controls the quick approach of the measured air pressure to the target air pressure, when the difference between the actual measurement air pressure and the target air pressure is small, the proportional-integral-derivative control method is used for realizing the control of the air pressure of the brake cavity, the actual measurement air pressure is ensured to gradually approach the target air pressure in a small step length, the controllability of the air pressure regulation is good, the error between the regulated air pressure of the brake cavity and the target air pressure is small, and the advantage of adaptive adjustment corresponding to different system parameters based on the integral differential control method enhances the system adaptability of air pressure control, even if the air inlet valve or the exhaust valve with different parameters is replaced, good air pressure control can be still realized, and therefore the dynamic response speed of the braking system is improved on the premise that good air pressure regulation controllability, small regulation error and strong system adaptability are guaranteed.
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without any creative work belong to the protection scope of the present invention.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be practiced in other embodiments that depart from the specific details disclosed herein, and it will be recognized by those skilled in the art that the present invention may be practiced without these specific details.
Next, the present invention is described in detail with reference to the schematic drawings, and in the detailed description of the embodiments of the present invention, the schematic drawings showing the structure of the device are not partially enlarged in general scale for convenience of description, and the schematic drawings are only examples, which should not limit the scope of the present invention. In addition, the three-dimensional dimensions of length, width and height should be included in the actual fabrication.
Fig. 1 is a schematic flow chart of a control method of a brake system according to an embodiment of the present invention. The method of the present embodiment may be performed by a control device of a braking system, which may be implemented in hardware and/or software, and may be generally integrated into a moving object, such as a vehicle, for achieving braking with high dynamic response speed.
Referring to fig. 1, a control method of a brake system may specifically include the following:
and 110, receiving measured air pressure and target air pressure, wherein the measured air pressure is the current brake cavity air pressure detected by the pressure sensor, and the target air pressure is the expected brake cavity air pressure.
The brake system may be in particular a pneumatic brake-by-wire system of a moving object, which may be for example a vehicle, more particularly a commercial vehicle.
Fig. 2 is a schematic diagram of a braking system according to an embodiment of the present invention. As shown in fig. 2, the braking system includes an Electronic Control Unit (ECU) 201, an air source 202, a line Control pneumatic valve 203 and an actuator 204, and for convenience of illustration, only the actuator 204 corresponding to one wheel is illustrated in fig. 2, and it is understood that the number of wheels is usually multiple, for example, the number of conventional vehicles is 4.
The gas source 202 is used for providing gas for the line control pneumatic valve 203, and comprises a gas pump 212 and a gas storage tank 222, wherein the gas pump 212 is used for extracting external gas into the gas storage tank 222, so that the gas pressure in the gas storage tank 222 is a preset gas pressure.
The line control pneumatic valve 203 includes a backup valve 213, an intake valve 223, an outlet valve 233, and a relay valve 243, wherein the backup valve 213 is of a redundant design and is in a normally closed state during normal operation of the brake system. The relay valve 243 includes a load chamber 301 and a control chamber 302, the pressure sensor 400 is disposed in the load chamber 301, the load chamber 301 is communicated with the brake chamber 214 of the actuator 204, and the air pressures of the two chambers are equal, so that the pressure sensor 400 may be disposed in the brake chamber 214 in other embodiments of the present embodiment.
The braking principle of the braking system is as follows: the user brakes the pedal, the displacement sensor connected with the pedal detects the displacement of the pedal, a corresponding brake signal is generated according to the displacement, the brake signal specifically comprises the target air pressure of the brake cavity, and the ECU201 receives the brake signal and extracts the target air pressure in the brake signal. The ECU201 controls the air pressure of the brake chamber by controlling the air inlet valve 223 and the air outlet valve 233 according to the target air pressure and the air pressure of the load chamber collected by the pressure sensor 400, and finally controls the air pressure of the brake chamber to be equal to the target air pressure, and pushes the brake cylinder piston 224 to apply a corresponding braking force to the friction block 234 and the brake disc 244, thereby completing braking. It is to be understood that, a cycle is defined from the last detection of the air pressure in the brake chamber by the pressure sensor 400 to the end of the current detection of the air pressure in the brake chamber by the pressure sensor 400, the one-time braking process includes a plurality of cycles that are continuously performed, the target air pressure in the present embodiment is the target air pressure in the current cycle, and the measured air pressure is the air pressure in the brake chamber 214 actually detected by the pressure sensor 400 in the current cycle, in this embodiment, the operations of the steps in the present embodiment are performed in a plurality of cycles in the one-time braking process.
Based on the braking principle of the braking system, the pressure sensor detects the air pressure of the braking cavity, the displacement sensor generates corresponding target air pressure according to the braking operation of the user, namely the air pressure of the braking cavity required when the braking force required by the braking operation of the user is achieved, namely the air pressure of the braking cavity which is expected to be achieved, and the ECU receives the air pressure of the braking cavity transmitted by the pressure sensor and the target air pressure transmitted by the displacement sensor.
It should be noted that the target air pressure is associated with the braking operation of the user, and when the braking operation of the user is changed, the target air pressure is changed accordingly.
And step 120, calculating the air pressure difference between the target air pressure and the measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference.
Let the target air pressure received by the ECU in step 110 be epMeasured air pressure is ecIf the difference e = e between the target air pressure and the measured air pressurep-ecAbsolute value of air pressure difference | e | = | ep-ec|。
The preset pressure difference is obtained by debugging the braking system, and the reasonable preset pressure difference can be determined through a large number of experiments. It can be understood that when the absolute value of the air pressure difference is greater than the preset pressure difference, the difference between the current air pressure of the brake chamber and the target air pressure is large, and when the absolute value of the air pressure difference is less than or equal to the preset pressure difference, the difference between the current air pressure of the brake chamber and the target air pressure is small.
And step 130, if the absolute value of the air pressure difference is greater than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressure increasing time or the pressure reducing time according to the measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram, and if the absolute value of the air pressure difference is smaller than the preset air pressure difference, determining the pressure increasing time or the pressure reducing time by adopting a proportional-integral-derivative control method so as to control the measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, thereby realizing the feedback control. The pressure increasing and decreasing characteristic diagram comprises a plurality of pressurizing characteristic curves and a plurality of pressure reducing characteristic curves, the pressurizing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressurizing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
Fig. 3 is a graph of pressure increase and decrease characteristics according to an embodiment of the present invention. As shown in fig. 3, the x-axis in the pressure increasing and decreasing characteristic diagram represents the measured air pressure in pascals; the y-axis represents air pressure difference in pascals. The curve with y larger than 0 is a characteristic curve of increasing pressure at a specific pressure increasing time, and a characteristic curve of reducing pressure at a specific pressure reducing time. For example, fig. 3 includes 10 boost characteristic curves and 10 decompression characteristic curves, where the 10 boost characteristic curves include curve 1, curve 2, curve 3, curve 4, curve 5, curve 6, curve 7, curve 8, curve 9 and curve 10, curve 1 is a boost characteristic curve of 10ms boost time, curve 2 is a boost characteristic curve of 9ms boost time, curve 3 is a boost characteristic curve of 8ms boost time, curve 4 is a boost characteristic curve of 7ms boost time, curve 5 is a boost characteristic curve of 6ms boost time, curve 6 is a boost characteristic curve of 5ms boost time, curve 7 is a boost characteristic curve of 4ms boost time, curve 8 is a boost characteristic curve of 3ms boost time, curve 9 is a boost characteristic curve of 2ms boost time, and curve 10 is a boost characteristic curve of 1ms boost time. The 10 decompression characteristic curves include a curve 11, a curve 12, a curve 13, a curve 14, a curve 15, a curve 16, a curve 17, a curve 18, a curve 19 and a curve 20, the curve 11 is a decompression characteristic curve of 10ms decompression time, the curve 12 is a decompression characteristic curve of 9ms decompression time, the curve 13 is a decompression characteristic curve of 8ms decompression time, the curve 14 is a decompression characteristic curve of 7ms decompression time, the curve 15 is a decompression characteristic curve of 6ms decompression time, the curve 16 is a decompression characteristic curve of 5ms decompression time, the curve 17 is a decompression characteristic curve of 4ms decompression time, the curve 18 is a decompression characteristic curve of 3ms decompression time, the curve 19 is a decompression characteristic curve of 2ms decompression time, and the curve 20 is a decompression characteristic curve of 1ms decompression time.
The maximum pressurization time and the maximum decompression time included in the pressure increase and decrease characteristic diagram are obtained through a large number of experiments on the basis of ensuring good controllability, small error and convenience in calculation of air pressure regulation. It can be understood that, when the disposable air pressure adjusting range is too large, because parts such as the pressure sensor have delay, the air pressure control cannot be executed according to preset conditions, the controllability is poor, the error between the finally adjusted air pressure and the target air pressure is large, and non-integers are not convenient to calculate.
In another embodiment of this embodiment, the pressure increasing/decreasing characteristic diagram may be a set including a pressure increasing characteristic diagram and a pressure decreasing characteristic diagram, wherein the pressure increasing characteristic diagram includes a plurality of pressure increasing characteristic curves, and the pressure decreasing characteristic diagram includes a plurality of pressure decreasing characteristic curves. And when a table look-up control method is adopted, the pressurization characteristic subgraph is inquired when the pressurization time needs to be determined, and the decompression characteristic subgraph is inquired when the decompression time needs to be determined.
The pressure difference range of the pressure increasing and decreasing characteristic diagram refers to the pressure difference range between the minimum pressure difference and the maximum pressure difference in the pressure increasing and decreasing characteristic diagram, for example, the pressure difference range of the pressure increasing and decreasing characteristic diagram in fig. 3 is-0.4 to 0.3 pa.
When the absolute value of the air pressure difference is larger than the preset pressure difference, namely the difference between the current air pressure of the brake cavity and the target air pressure is large, the air pressure of the brake cavity is controlled by adopting a table look-up control method, and in order to ensure the realizability of the table look-up control method, when the absolute value of the air pressure difference is judged to be larger than the preset pressure difference, whether the air pressure difference is located in the pressure difference range of the pressure increasing and decreasing characteristic diagram is further determined, and the pressure increasing time or the pressure reducing time can be obtained by inquiring the pressure increasing and decreasing characteristic diagram. The absolute value of the air pressure difference is smaller than the preset pressure difference, and the description is omitted here.
In the actual table look-up process, the air pressure difference between the target air pressure and the measured air pressure is obtained through calculation, the abscissa of the table is the measured air pressure, and the ordinate of the table is the position of the air pressure difference. It should be noted that each of the pressurization times and the depressurization times in the pressure increase/decrease characteristic diagram are set separately, and if the pressure difference between the target pressure and the actual pressure is between two adjacent pressurization characteristic curves, the time corresponding to any one of the two pressurization characteristic curves is selected as the pressurization time. Preferably, if the pressure difference between the target pressure and the measured pressure is between two adjacent supercharging characteristic curves, selecting the smaller corresponding time in the two supercharging characteristic curves as supercharging time; if the air pressure difference between the target air pressure and the actually measured air pressure is between two adjacent decompression characteristic curves, the corresponding time in the two decompression characteristic curves is selected to be smaller as the supercharging time, so that the problem of over-supercharging or over-decompression caused by too long supercharging time or decompression time is avoided.
Specifically, the period from the last detection of the air pressure of the brake cavity by the pressure sensor to the current detection of the air pressure of the brake cavity by the pressure sensor is one period.
The technical scheme provided by this embodiment includes receiving an actual measurement air pressure and a target air pressure, where the actual measurement air pressure is a current brake cavity air pressure detected by a pressure sensor, and the target air pressure is a brake cavity air pressure expected to be reached, calculating an air pressure difference between the target air pressure and the actual measurement air pressure, comparing an absolute value of the air pressure difference with a preset pressure difference, determining a pressurization time or a depressurization time according to the actual measurement air pressure, the air pressure difference, and an increasing/decreasing characteristic diagram if the absolute value of the air pressure difference is greater than the preset pressure difference, and determining the pressurization time or the depressurization time by using a proportional-integral-derivative control method if the absolute value of the air pressure difference is less than the preset pressure difference, so as to control the actual measurement air pressure to gradually approach the target air pressure until the brake cavity air pressure reaches the target air pressure, thereby realizing feedback control of the brake cavity air pressure, and making the actual measurement, the brake system can realize the control of the air pressure of the brake cavity by a convenient table look-up control method, does not need a complex calculation process, controls the quick approach of the measured air pressure to the target air pressure, when the difference between the actual measurement air pressure and the target air pressure is small, the proportional-integral-derivative control method is used for realizing the control of the air pressure of the brake cavity, the actual measurement air pressure is ensured to gradually approach the target air pressure in a small step length, the controllability of the air pressure regulation is good, the error between the regulated air pressure of the brake cavity and the target air pressure is small, and the advantage of adaptive adjustment corresponding to different system parameters based on the integral differential control method enhances the system adaptability of air pressure control, even if the air inlet valve or the exhaust valve with different parameters is replaced, good air pressure control can be still realized, and therefore the dynamic response speed of the braking system is improved on the premise that good air pressure regulation controllability, small regulation error and strong system adaptability are guaranteed.
Fig. 4 is a flowchart illustrating a control method of a brake system according to another embodiment of the present invention. The present embodiment further optimizes the control method of the brake system based on the above embodiments. And setting the time corresponding to the maximum value as the pressurization time if the air pressure difference is larger than the maximum value of the pressure difference range of the pressure increasing and reducing characteristic diagram, and setting the time corresponding to the minimum value as the depressurization time if the air pressure difference is smaller than the minimum value of the pressure difference range of the pressure increasing and reducing characteristic diagram.
Specifically, as shown in fig. 4, the control method of the brake system provided in this embodiment may include the following steps:
and step 21, receiving the measured air pressure and the target air pressure, wherein the measured air pressure is the current brake cavity air pressure detected by the pressure sensor, and the target air pressure is the expected brake cavity air pressure.
And step 22, calculating the air pressure difference between the target air pressure and the actually measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference.
Step 23, if the absolute value of the air pressure difference is greater than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressurization time or the depressurization time according to the actually measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram; if the absolute value of the air pressure difference is smaller than the preset pressure difference, determining the pressurization time or the decompression time by adopting a proportional-integral-derivative control method; the measured air pressure is controlled to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, and the feedback control of the air pressure of the brake cavity is realized.
And 24, if the air pressure difference is larger than the maximum value of the pressure difference range of the pressure increasing and reducing characteristic diagram, taking the time corresponding to the maximum value as the pressure increasing time, and if the air pressure difference is smaller than the minimum value of the pressure difference range of the pressure increasing and reducing characteristic diagram, taking the time corresponding to the minimum value as the pressure reducing time.
When the air pressure difference is greater than the maximum value of the pressure difference range of the pressure increasing and decreasing characteristic diagram or the air pressure difference is less than the minimum value of the pressure difference range of the pressure increasing and decreasing characteristic diagram, the air pressure difference between the target air pressure and the measured air pressure exceeds the pressure difference range of the pressure increasing and decreasing characteristic diagram, and the specific corresponding supercharging time or decompression time cannot be accurately searched on the pressure increasing and decreasing characteristic diagram. The embodiment adopts the maximum pressurization time or the maximum decompression time in the pressure increasing and decreasing characteristic diagram to control the regulation of the air pressure of the brake cavity, and on the basis of ensuring good controllability, small error and convenient calculation of the air pressure regulation, the maximum valve opening time is the maximum pressurization time or the maximum decompression time, so that the air pressure regulation is carried out quickly, and the response speed of the system is improved.
For example, in fig. 3, the maximum pressure-increasing time and the maximum pressure-decreasing time of the pressure-increasing/decreasing characteristic diagram are 10ms and 10ms, respectively, when the absolute value of the difference between the target air pressure and the measured air pressure is greater than the preset difference and greater than the maximum pressure difference of the pressure-increasing/decreasing characteristic diagram, 10ms is selected as the pressure-increasing time, and when the absolute value of the difference between the target air pressure and the measured air pressure is greater than the preset difference and less than the minimum pressure difference of the pressure-increasing/decreasing characteristic diagram, 10ms is selected as the pressure-decreasing time.
Fig. 5 is a flowchart illustrating a control method of a brake system according to another embodiment of the present invention. In this embodiment, on the basis of the above embodiment, the step of calculating the air pressure difference between the target air pressure and the measured air pressure, and comparing the absolute value of the air pressure difference with the preset air pressure difference is further optimized, and after the air pressure difference between the target air pressure and the measured air pressure is calculated, the step of compensating the air pressure difference is performed, and the compensated air pressure difference is used as a new air pressure difference.
Specifically, referring to fig. 5, the control method of the brake system provided in this embodiment may include the following steps:
and 41, receiving the actually measured air pressure and the target air pressure, wherein the actually measured air pressure is the current brake cavity air pressure detected by the pressure sensor, and the target air pressure is the expected brake cavity air pressure.
And 42, calculating the air pressure difference between the target air pressure and the actually measured air pressure, compensating the air pressure difference, taking the compensated air pressure difference as a new air pressure difference, and comparing the absolute value of the air pressure difference with a preset pressure difference.
It will be appreciated that the essential meaning of comparing the air pressure difference and the absolute value with the preset pressure difference in step 42 is: the new absolute value of the air pressure difference is compared with the preset pressure difference.
The pressure acquisition operation of the pressure sensor has delay, namely the pressure sensor can acquire the air pressure after a period of time after the acquisition starting moment, and for a relay valve load cavity with frequent air pressure change, the air pressure data acquired by the pressure sensor at a certain moment has errors, and the errors can cause errors in the determination of the time for increasing or reducing.
In the embodiment, after the air pressure difference between the target air pressure and the measured air pressure is calculated, the air pressure difference is compensated, so that the error caused by the air pressure data acquisition delay of the pressure sensor is reduced or even eliminated.
Optionally, the air pressure difference is compensated by using the following formula one:
e=ep+βem(ii) a A formula of
Wherein e is the compensated air pressure difference; beta is a compensation coefficient; e.g. of the typepThe measured air pressure is obtained; e.g. of the typem=△pr-△pt；△pr =pc(k)- pc(k-1)；△pt = pt(k-1)- pc(k-1)； pc(k)The air pressure of the brake cavity collected by the pressure sensor in the current period is measured; p is a radical ofc(k-1)The pressure of the brake cavity is acquired by the pressure sensor in the last period; p is a radical oft(k-1)The target air pressure of the previous period, wherein the period from the last detection of the air pressure of the brake cavity by the pressure sensor to the current detection of the air pressure of the brake cavity by the pressure sensor is ended.
In the feedback of the air pressure closed loop control of the brake cavity formed by the pressure sensor and the ECU, the pressure sensor starts a period every time when acquiring the measured air pressure of the brake cavity, and the period is finished until the ECU controls the air inlet valve or the air outlet valve to complete the adjustment of the air pressure of the brake cavity based on the measured air pressure.
It can be understood that the target air pressure is controlled in real time by the braking operation of the user, and thus the target air pressures in adjacent periods may be different, and the target air pressure in the previous period is the target air pressure in the previous period of the current period. The embodiment compensates the error generated in the previous period in the current period, and the like, so that the real-time compensation of the error is realized, and the timeliness and the accuracy of the error compensation are ensured.
The compensation coefficient beta can be set according to the performance of the braking system and the type of the error to be compensated, and can be reasonably adjusted by taking accurate compensation of the error as a target.
And 43, if the absolute value of the air pressure difference is greater than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressure increasing time or the pressure reducing time according to the measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram, and if the absolute value of the air pressure difference is smaller than the preset air pressure difference, determining the pressure increasing time or the pressure reducing time by adopting a proportional-integral-derivative control method so as to control the measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, thereby realizing the feedback control of. The pressure increasing and decreasing characteristic diagram comprises a plurality of pressurizing characteristic curves and a plurality of pressure reducing characteristic curves, the pressurizing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressurizing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
Fig. 6 is a flowchart illustrating a control method of a brake system according to another embodiment of the present invention. On the basis of the above embodiments, the present embodiment further optimizes a control method of the brake system, and before setting to receive the measured air pressure and the target air pressure, the method further includes: and estimating the actual measurement air pressure of the pressure sensor in the current period as the estimated air pressure based on the determined pressure increasing time or pressure reducing time in the previous period and a preset estimation model, and if the difference value of the actual measurement air pressure and the estimated air pressure is greater than a preset difference value, taking the estimated air pressure as the actual measurement air pressure in the current period, wherein the period is from the last detection of the pressure sensor on the air pressure of the brake cavity to the current detection of the pressure sensor on the air pressure of the brake cavity.
Specifically, referring to fig. 6, the method of the braking system provided in this embodiment specifically includes the following steps:
and step 51, estimating the measured air pressure of the pressure sensor in the current period as the estimated air pressure based on the determined pressurization time or depressurization time in the previous period and a preset estimation model.
The estimation model is a preset model, and can accurately estimate the actually measured air pressure obtained in the current period based on the determined pressure increasing time or pressure reducing time in the previous period and the performance of the brake system.
It is understood that the estimated air pressure is substantially an estimated value obtained by the estimation model, and is not an actual air pressure value.
And step 52, if the difference value between the measured air pressure and the estimated air pressure is greater than the preset difference value, taking the estimated air pressure as the measured air pressure of the current period, wherein the period is from the last detection of the pressure sensor on the air pressure of the brake cavity to the end of the current detection of the pressure sensor on the air pressure of the brake cavity.
It can be understood that, the difference between the estimated air pressure obtained based on the accurate estimation model and the actual measured air pressure of the brake cavity actually detected by the pressure sensor in the current period is necessarily not large, that is, the difference is close to the actual air pressure of the brake cavity in the current period, when the difference between the actual measured air pressure and the estimated air pressure is larger than the preset difference, that is, the difference between the actual measured air pressure and the estimated air pressure is larger than the preset difference, it can be determined that the pressure sensor has a fault, and the air pressure of the brake cavity is controlled by continuously adopting the air pressure value detected by the pressure sensor, which may cause the problem of.
The estimated air pressure is close to the actual air pressure of the brake cavity, the feasibility of directly applying the estimated air pressure to the air pressure control of the brake cavity is realized, the accuracy is good, safety accidents caused by faults of the pressure sensor can be avoided, and the driving safety is improved.
And 53, receiving the measured air pressure and the target air pressure, wherein the measured air pressure is the current brake cavity air pressure detected by the pressure sensor, and the target air pressure is the expected brake cavity air pressure.
And step 54, calculating the air pressure difference between the target air pressure and the actually measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference.
And step 55, if the absolute value of the air pressure difference is greater than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressure increasing time or the pressure reducing time according to the measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram, and if the absolute value of the air pressure difference is smaller than the preset air pressure difference, determining the pressure increasing time or the pressure reducing time by adopting a proportional-integral-derivative control method so as to control the measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, thereby realizing the feedback control. The pressure increasing and decreasing characteristic diagram comprises a plurality of pressurizing characteristic curves and a plurality of pressure reducing characteristic curves, the pressurizing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressurizing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
Fig. 7 is a flowchart illustrating a control method of a brake system according to another embodiment of the present invention. In this embodiment, on the basis of the above embodiment, after further optimizing the control method of the brake system and setting and judging that the difference between the measured air pressure and the estimated air pressure is greater than the preset difference, the method further includes: and carrying out alarm prompt in a preset mode.
Specifically, referring to fig. 7, the method of the braking system provided in this embodiment specifically includes the following steps:
and step 61, estimating the actually measured air pressure of the pressure sensor in the current period as the estimated air pressure based on the determined pressurization time or depressurization time in the previous period and a preset estimation model.
And step 62, if the difference value between the measured air pressure and the estimated air pressure is greater than the preset difference value, taking the estimated air pressure as the measured air pressure of the current period, wherein the period is from the last detection of the pressure sensor on the air pressure of the brake cavity to the end of the current detection of the pressure sensor on the air pressure of the brake cavity.
And 63, carrying out alarm prompting in a preset mode.
The preset mode can be one or more of sound, text or visual signals, for example, a combination of "pressure sensor failure" is displayed on the user interaction interface, the control indicator lamp continuously flashes, and the control indicator tone is turned on at the same time. The embodiment does not limit the specific alarm mode, and all alarm modes capable of prompting the user are within the protection range of the embodiment.
The difference value of the measured air pressure and the estimated air pressure is larger than the preset difference value, the failure of the pressure sensor is explained, the driving safety is affected, the failure of the pressure sensor is reminded to a user in an alarm prompting mode, the pressure sensor is overhauled in time, and the accident is avoided.
And step 64, receiving the measured air pressure and the target air pressure, wherein the measured air pressure is the current brake cavity air pressure detected by the pressure sensor, and the target air pressure is the expected brake cavity air pressure.
And step 65, calculating the air pressure difference between the target air pressure and the actually measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference.
And step 66, if the absolute value of the air pressure difference is greater than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressure increasing time or the pressure reducing time according to the measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram, and if the absolute value of the air pressure difference is smaller than the preset air pressure difference, determining the pressure increasing time or the pressure reducing time by adopting a proportional-integral-derivative control method so as to control the measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, thereby realizing the feedback control. The pressure increasing and decreasing characteristic diagram comprises a plurality of pressurizing characteristic curves and a plurality of pressure reducing characteristic curves, the pressurizing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressurizing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
Fig. 8 is a flowchart illustrating a control method of a brake system according to another embodiment of the present invention. On the basis of the above embodiments, the present embodiment further optimizes the control method of the brake system, and before setting and calculating the air pressure difference between the measured air pressure and the target air pressure, the method further includes: and acquiring a pressure increase and decrease characteristic diagram.
Specifically, referring to fig. 8, the control method of the brake system provided in this embodiment may include the following steps:
and step 71, receiving measured air pressure and target air pressure, wherein the measured air pressure is the current brake cavity air pressure detected by the pressure sensor, and the target air pressure is the expected brake cavity air pressure.
And step 72, acquiring a pressure increasing and decreasing characteristic diagram.
The mode of acquiring the pressure increasing/decreasing characteristic map by the ECU may be, for example, a pressure increasing/decreasing characteristic map directly input from the outside, or an ECU obtained by an experiment or simulation in cooperation with other components of the vehicle.
The step of obtaining the pressure increasing and decreasing characteristic diagram ensures that the table lookup braking method in the control method of the braking system provided by the embodiment of the invention is normally carried out.
Optionally, the obtaining of the pressure increase/decrease characteristic diagram includes: the method comprises the steps of periodically controlling the opening and closing of an air inlet valve respectively at a plurality of preset pressurization time until the actually measured pressure of a brake cavity is equal to the air pressure of an air source so as to obtain a plurality of pressurization characteristic curves in a pressure increasing and decreasing characteristic diagram, and periodically controlling the opening and closing of an air outlet valve respectively at a plurality of preset pressure reducing time until the actually measured pressure of the brake cavity is equal to the air pressure of the air source so as to obtain a plurality of pressure reducing characteristic curves in the pressure increasing and decreasing characteristic diagram.
Taking fig. 3 as an example, a plurality of preset supercharging times, i.e., 1ms, 2ms, 3ms, 4ms, 5ms, 6ms, 7ms, 8ms, 9ms and 10ms, are specifically described as follows, further taking an example of obtaining a supercharging characteristic curve of 1 ms: 1. determining a cycle duration, for example, the cycle duration is 0.5 s; 2. the ECU controls an air outlet valve in the brake system shown in the figure 2 to be closed, an air inlet valve is opened for 1ms, then the air inlet valve is controlled to be closed for 499ms, at this time, one period is ended, then the periodic operation is repeatedly carried out until the air pressure of a brake cavity is equal to the air pressure of an air source, namely the air pressure fed back to the ECU by a pressure sensor is equal to the pre-stored air pressure of the air source, and then a 1ms pressurization characteristic curve is obtained. Characteristic curves of 2ms, 3ms, 4ms, 5ms, 6ms, 7ms, 8ms, 9ms and 10ms are obtained in the same manner in this order.
Similarly, a plurality of preset decompression times, i.e., 1ms, 2ms, 3ms, 4ms, 5ms, 6ms, 7ms, 8ms, 9ms and 10ms, are specifically described below by taking the example of obtaining a decompression characteristic curve of 1ms as an example: 1. determining a cycle duration, for example, the cycle duration is 0.5 s; 2. the ECU controls an air inlet valve in the brake system shown in the figure 2 to be closed, an air outlet valve is opened for 1ms, then the air inlet valve is controlled to be closed for 499ms, at this time, one period is ended, then the periodic operation is repeatedly carried out until the air pressure of a brake cavity is equal to the air pressure of an air source, namely the air pressure fed back to the ECU by a pressure sensor is equal to the pre-stored air pressure of the air source, and then a pressure reduction characteristic curve of 1ms is obtained. Characteristic curves of 2ms, 3ms, 4ms, 5ms, 6ms, 7ms, 8ms, 9ms and 10ms are obtained in the same manner in this order.
Finally, the plurality of supercharging characteristic curves and the plurality of decompression characteristic curves obtained as described above are integrated into the same coordinate to form a supercharging and decompression characteristic diagram shown in fig. 2.
It can be understood that the execution method of the specific example corresponding to fig. 3 may be implemented in an experimental manner or a simulation manner, and this embodiment is not particularly limited to this.
The specific setting of each pressure increasing time and each pressure decreasing time in the pressure increasing/decreasing characteristic diagram is determined according to actual needs and the performance of the brake system, and the case shown in fig. 3 is only used as an exemplary illustration and is not limited.
And 73, calculating the air pressure difference between the target air pressure and the actually measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference.
And step 74, if the absolute value of the air pressure difference is greater than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressure increasing time or the pressure reducing time according to the measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram, and if the absolute value of the air pressure difference is smaller than the preset air pressure difference, determining the pressure increasing time or the pressure reducing time by adopting a proportional-integral-derivative control method so as to control the measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, thereby realizing the feedback control. The pressure increasing and decreasing characteristic diagram comprises a plurality of pressurizing characteristic curves and a plurality of pressure reducing characteristic curves, the pressurizing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressurizing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
Fig. 9 is a schematic structural diagram of a control device of a brake system according to an embodiment of the present invention. As shown in fig. 9, the control device of the brake system may specifically include:
the air pressure receiving module 81 is configured to receive an actual measurement air pressure and a target air pressure, where the actual measurement air pressure is a current brake cavity air pressure detected by the pressure sensor, and the target air pressure is a brake cavity air pressure expected to be reached;
the air pressure difference calculating module 82 is used for calculating the air pressure difference between the target air pressure and the measured air pressure and comparing the absolute value of the air pressure difference with a preset pressure difference;
a first time determination module 83, configured to, when the absolute value of the air pressure difference is greater than the preset pressure difference and the air pressure difference is within the pressure difference range of the pressure increase/decrease characteristic diagram, determining the pressurization time or the depressurization time according to the measured air pressure, the air pressure difference and the pressure increase and decrease characteristic diagram, when the absolute value of the air pressure difference is smaller than the preset pressure difference, the pressure increasing time or the pressure reducing time is determined by adopting a proportional-integral-derivative control method, so as to control the actually measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, thereby realizing the feedback control of the air pressure of the brake cavity, the pressure increasing and reducing characteristic diagram comprises a plurality of pressure increasing characteristic curves and a plurality of pressure reducing characteristic curves, the pressure increasing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressure increasing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
The control device of the brake system provided by the embodiment can execute the control method of the brake system provided by any embodiment of the invention, and specifically executes the corresponding functional modules and beneficial effects of the method.
Further, in the above technical solution, the control device of the brake system further includes:
the second time determination module is used for determining the pressurization time or the depressurization time according to the maximum value, the air pressure difference and the pressure increasing and reducing characteristic diagram when the air pressure difference is larger than the maximum value of the pressure difference range of the pressure increasing and reducing characteristic diagram;
and the third time determination module is used for determining the pressurization time or the depressurization time according to the minimum value, the air pressure difference and the pressure increasing and reducing characteristic diagram when the air pressure difference is smaller than the minimum value of the pressure difference range of the pressure increasing and reducing characteristic diagram.
Further, on the basis of the above technical solution, the control device of the brake system further includes:
and the pressure difference compensation module is used for compensating the air pressure difference after calculating the air pressure difference between the target air pressure and the measured air pressure, and taking the compensated air pressure difference as a new air pressure difference.
Further, on the basis of the above technical solution, the control device of the brake system further includes:
the air pressure estimation module is used for estimating the actual measurement air pressure of the pressure sensor in the current period as the estimated air pressure based on the determined pressurization time or the determined decompression time in the previous period and a preset estimation model before receiving the actual measurement air pressure and the target air pressure;
and the air pressure determining module is used for taking the estimated air pressure as the measured air pressure of the current period when the difference value of the measured air pressure and the estimated air pressure is greater than the preset difference value, wherein the period is from the last detection of the pressure sensor on the air pressure of the brake cavity to the current detection of the pressure sensor on the air pressure of the brake cavity.
Further, on the basis of the above technical solution, the control device of the brake system further includes:
and the fault prompting module is used for alarming and prompting in a preset mode after judging that the absolute value of the difference value of the measured air pressure and the estimated air pressure is greater than a preset difference value.
Further, on the basis of the above technical solution, the control device of the brake system further includes:
and the characteristic diagram acquisition module is used for acquiring the pressure increasing and decreasing characteristic diagram before calculating the air pressure difference between the measured air pressure and the target air pressure.
Further, on the basis of the above technical solution, the characteristic diagram obtaining module includes:
the boost curve acquisition unit is used for periodically controlling the opening and closing of the air inlet valve under a plurality of preset boost time respectively until the actually measured pressure of the brake cavity is equal to the air pressure of the air source so as to obtain a plurality of boost characteristic curves in the pressure increase and decrease characteristic diagram;
and the decompression curve acquisition unit is used for periodically controlling the opening and closing of the air outlet valve under a plurality of preset decompression time respectively until the actually measured pressure of the brake cavity is equal to the air pressure of the air source so as to obtain a plurality of decompression characteristic curves in the decompression characteristic diagram.
Fig. 10 is a schematic structural diagram of an apparatus according to an embodiment of the present invention. As shown in fig. 10, the apparatus includes a processor 90, a memory 91, an input device 92, and an output device 93; the number of processors 90 in the device may be one or more, and one processor 90 is taken as an example in fig. 10; the processor 90, the memory 91, the input device 92 and the output device 93 in the apparatus may be connected by a bus or other means, and the bus connection is exemplified in fig. 10.
The memory 91 serves as a computer-readable storage medium, and may be used to store software programs, computer-executable programs, and modules, such as program instructions/modules corresponding to the control method of the brake system in the embodiment of the present invention (for example, the air pressure receiving module 81, the air pressure difference calculating module 82, and the first time determining module 83 included in the control apparatus of the brake system). The processor 90 executes various functional applications of the server and data processing by executing software programs, instructions, and modules stored in the memory 91, that is, implements the control method of the brake system described above.
The memory 91 may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program required for at least one function; the storage data area may store data created according to the use of the terminal, and the like. Further, the memory 91 may include high speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device. In some examples, memory 91 may further include memory located remotely from processor 90, which may be connected to a server over a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.
The input device 92 may be used to receive input numeric or character information and generate key signal inputs related to user settings and function control of the server. The output device 93 may include a display server such as a display screen.
Embodiments of the present invention also provide a storage medium containing computer-executable instructions which, when executed by a computer processor, perform a method of controlling a brake system, the method comprising:
receiving actual measurement air pressure and target air pressure, wherein the actual measurement air pressure is the current brake cavity air pressure detected by a pressure sensor, and the target air pressure is the expected brake cavity air pressure;
calculating the air pressure difference between the target air pressure and the measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference;
if the absolute value of the air pressure difference is larger than the preset pressure difference and the air pressure difference is within the pressure difference range of the pressure increasing and decreasing characteristic diagram, determining the pressurization time or the depressurization time according to the actually measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram; if the absolute value of the air pressure difference is smaller than the preset pressure difference, determining the pressurization time or the decompression time by adopting a proportional-integral-derivative control method; controlling the actually measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, and realizing feedback control of the air pressure of the brake cavity;
the pressure increasing and decreasing characteristic diagram comprises a plurality of pressurizing characteristic curves and a plurality of pressure reducing characteristic curves, the pressurizing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressurizing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
Of course, the storage medium containing the computer-executable instructions provided by the embodiment of the present invention is not limited to the method operations described above, and may also perform related operations in the control method of the brake system provided by any embodiment of the present invention.
From the above description of the embodiments, it is obvious for those skilled in the art that the present invention can be implemented by software and necessary general hardware, and certainly, can also be implemented by hardware, but the former is a better embodiment in many cases. Based on such understanding, the technical solutions of the present invention may be embodied in the form of a software product, which can be stored in a computer-readable storage medium, such as a floppy disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a FLASH Memory (FLASH), a hard disk or an optical disk of a computer, and includes several instructions for enabling a computer device (which may be a personal computer, a server, or a network device) to execute the methods according to the embodiments of the present invention.
It should be noted that, in the embodiment of the control device of the braking system, the included units and modules are merely divided according to the functional logic, but are not limited to the above division as long as the corresponding functions can be realized; in addition, specific names of the functional units are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present invention.
It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious modifications, rearrangements, combinations and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims (11)

1. A control method of a brake system, characterized by comprising:
receiving actual measurement air pressure and target air pressure, wherein the actual measurement air pressure is the current brake cavity air pressure detected by a pressure sensor, and the target air pressure is the expected brake cavity air pressure;
calculating the air pressure difference between the target air pressure and the measured air pressure, and comparing the absolute value of the air pressure difference with a preset pressure difference;
if the absolute value of the air pressure difference is larger than the preset air pressure difference and the air pressure difference is within the range of the air pressure difference of the pressure increasing and decreasing characteristic diagram, determining the pressurization time or the depressurization time according to the actually measured air pressure, the air pressure difference and the pressure increasing and decreasing characteristic diagram; if the absolute value of the air pressure difference is smaller than the preset pressure difference, determining the pressurization time or the decompression time by adopting a proportional-integral-derivative control method; controlling the actually measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, and realizing feedback control of the air pressure of the brake cavity;
the pressure increasing and reducing characteristic diagram comprises a plurality of pressure increasing characteristic curves and a plurality of pressure reducing characteristic curves, the pressure increasing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressure increasing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
2. The control method according to claim 1, characterized in that, if the air pressure difference is larger than a maximum value of a differential pressure range of the pressure increase/decrease characteristic map, a time corresponding to the maximum value is taken as the supercharging time;
and if the air pressure difference is smaller than the minimum value of the pressure difference range of the pressure increase/decrease characteristic diagram, setting the time corresponding to the minimum value as the decompression time.
3. The control method of claim 1, wherein calculating the air pressure difference between the target air pressure and the measured air pressure further comprises:
and compensating the air pressure difference, and taking the compensated air pressure difference as a new air pressure difference.
4. The control method according to claim 3, characterized in that the air pressure difference is compensated using the following formula:
e=ep+βem;
wherein e is the compensated air pressure difference; beta is a compensation coefficient; e.g. of the typepIs the measured air pressure; e.g. of the typem=pr-△pt；△pr =pc(k)- pc(k-1)；△pt = pt(k-1)- pc(k-1)； pc(k)For the pressure sensor to be presentThe air pressure of the brake cavity is collected in a period; p is a radical ofc(k-1)The air pressure of the brake cavity collected by the pressure sensor in the last period is measured; p is a radical oft(k-1)The target air pressure of the previous period, wherein the period from the last detection of the air pressure of the brake cavity by the pressure sensor to the current detection of the air pressure of the brake cavity by the pressure sensor is one.
5. The control method of claim 1, wherein receiving the measured air pressure and the target air pressure further comprises:
estimating the actual measurement air pressure of the pressure sensor in the current period as the estimated air pressure based on the determined pressurization time or the determined depressurization time in the previous period and a preset estimation model;
if the difference value between the actually measured air pressure and the estimated air pressure is larger than a preset difference value, taking the estimated air pressure as the actually measured air pressure of the current period;
and the period from the last detection of the air pressure of the brake cavity by the pressure sensor to the current detection of the air pressure of the brake cavity by the pressure sensor is one.
6. The method of claim 5, wherein after determining that the absolute value of the difference between the measured air pressure and the estimated air pressure is greater than a predetermined difference, the method further comprises:
and carrying out alarm prompt in a preset mode.
7. The control method of claim 1, wherein calculating the air pressure difference between the measured air pressure and the target air pressure further comprises:
and acquiring the pressure increasing and decreasing characteristic diagram.
8. The control method according to claim 7, wherein the acquiring the pressure increase/decrease characteristic map includes:
the opening and closing of the air inlet valve are periodically controlled under a plurality of preset pressurization time respectively until the actually measured pressure of the brake cavity is equal to the air pressure of the air source, so that a plurality of pressurization characteristic curves in the pressure increasing and decreasing characteristic diagram are obtained;
and periodically controlling the opening and closing of the air outlet valve under a plurality of preset pressure reduction time respectively until the actually measured pressure of the brake cavity is equal to the air pressure of the air source so as to obtain a plurality of pressure reduction characteristic curves in the pressure increase and decrease characteristic diagram.
9. A control device for a brake system, comprising:
the air pressure receiving module is used for receiving measured air pressure and target air pressure, wherein the measured air pressure is the current brake cavity air pressure detected by the pressure sensor, and the target air pressure is the expected brake cavity air pressure;
the air pressure difference calculating module is used for calculating the air pressure difference between the target air pressure and the measured air pressure and comparing the absolute value of the air pressure difference with a preset pressure difference;
the first time determination module is used for determining the pressurization time or the depressurization time according to the measured air pressure, the air pressure difference and the pressure increasing and reducing characteristic diagram when the absolute value of the air pressure difference is larger than the preset air pressure and the air pressure difference is within the pressure difference range of the pressure increasing and reducing characteristic diagram, and determining the pressurization time or the depressurization time by adopting a proportional-integral-derivative control method when the absolute value of the air pressure difference is smaller than the preset pressure difference so as to control the measured air pressure to gradually approach the target air pressure until the air pressure of the brake cavity reaches the target air pressure, thereby realizing the feedback control of the air pressure of the brake cavity;
the pressure increasing and reducing characteristic diagram comprises a plurality of pressure increasing characteristic curves and a plurality of pressure reducing characteristic curves, the pressure increasing characteristic curves are change curves of pressure difference along with actual measurement air pressure under a plurality of different pressure increasing time, and the pressure reducing characteristic curves are change curves of the pressure difference along with the actual measurement air pressure under a plurality of different pressure reducing time.
10. An apparatus, characterized in that the apparatus comprises:
one or more processors;
a storage device for storing one or more programs,
when executed by the one or more processors, cause the one or more processors to implement a control method of a brake system according to any one of claims 1-8.
11. A computer-readable storage medium, on which a computer program is stored, which program, when being executed by a processor, is adapted to carry out a method of controlling a brake system according to any one of claims 1-8.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113335252A (en) * 2021-07-21 2021-09-03 福建中科云杉信息技术有限公司 Air pressure adjusting method for air brake and air brake control system

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006032657A1 (en) * 2004-09-24 2006-03-30 Continental Teves Ag & Co. Ohg Method and device for supporting a brake system in case of reduced effectiveness
CN104395161A (en) * 2012-06-25 2015-03-04 株式会社爱德克斯 Braking control device for vehicle
CN104583033A (en) * 2012-08-29 2015-04-29 大陆-特韦斯贸易合伙股份公司及两合公司 Switchover method for a solenoid valve operated in analogized form, electrohydraulic brake system, and use of the electrohydraulic brake system
CN105050871A (en) * 2013-03-15 2015-11-11 株式会社爱德克斯 Electric braking device for vehicle
DE102018213935A1 (en) * 2018-08-17 2020-02-20 Robert Bosch Gmbh HBA threshold pressure adjustment method and apparatus for performing the method
CN111231917A (en) * 2020-02-26 2020-06-05 中国地质大学（北京） Vehicle braking pressure regulation and control method based on air pressure line control braking system
CN111422176A (en) * 2020-02-26 2020-07-17 中国地质大学（北京） Distributed line control brake system and control method for commercial vehicle
CN112248990A (en) * 2020-12-24 2021-01-22 天津所托瑞安汽车科技有限公司 Pneumatic parking system and parking control method thereof

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006032657A1 (en) * 2004-09-24 2006-03-30 Continental Teves Ag & Co. Ohg Method and device for supporting a brake system in case of reduced effectiveness
CN104395161A (en) * 2012-06-25 2015-03-04 株式会社爱德克斯 Braking control device for vehicle
CN104583033A (en) * 2012-08-29 2015-04-29 大陆-特韦斯贸易合伙股份公司及两合公司 Switchover method for a solenoid valve operated in analogized form, electrohydraulic brake system, and use of the electrohydraulic brake system
CN105050871A (en) * 2013-03-15 2015-11-11 株式会社爱德克斯 Electric braking device for vehicle
DE102018213935A1 (en) * 2018-08-17 2020-02-20 Robert Bosch Gmbh HBA threshold pressure adjustment method and apparatus for performing the method
CN111231917A (en) * 2020-02-26 2020-06-05 中国地质大学（北京） Vehicle braking pressure regulation and control method based on air pressure line control braking system
CN111422176A (en) * 2020-02-26 2020-07-17 中国地质大学（北京） Distributed line control brake system and control method for commercial vehicle
CN112298137A (en) * 2020-02-26 2021-02-02 中国地质大学（北京） Control method of commercial vehicle air pressure braking system and whole vehicle braking method
CN112298141A (en) * 2020-02-26 2021-02-02 中国地质大学（北京） Control method of whole vehicle brake system
CN112248990A (en) * 2020-12-24 2021-01-22 天津所托瑞安汽车科技有限公司 Pneumatic parking system and parking control method thereof

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113335252A (en) * 2021-07-21 2021-09-03 福建中科云杉信息技术有限公司 Air pressure adjusting method for air brake and air brake control system

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