阅读说明：本技术 一种发动机制动功率控制方法及系统 (Engine braking power control method and system ) 是由 史美丽 杨立云 满凯 许雪利 杨秀花 于 2019-09-30 设计创作，主要内容包括：本申请提供一种发动机制动功率控制方法及系统,当接收到制动控制指令时,首先,根据预设初始参数对发动机进行初始制动控制；之后,按照预设时间间隔获取各个数据采集点所对应的行车车速；然后,根据各个数据采集点所对应的行车车速计算相应的目标输出制动功率,根据该目标输出制动功率查表确定对应的目标参数,最后,控制增压器电控放气阀、进气节流阀和多个制动电磁阀达到目标参数对应的状态,减少了对行车制动的使用频率,增加了行车制动器的使用寿命,同时,在整车下长坡行车时降低了司机对整车操作的次数,从而减小了司机劳动强度,提高了整车下长坡行车时的安全性。(When a braking control command is received, firstly, performing initial braking control on an engine according to preset initial parameters; then, acquiring the driving speed corresponding to each data acquisition point according to a preset time interval; and finally, controlling a supercharger electric control air release valve, an air inlet throttle valve and a plurality of brake solenoid valves to reach a state corresponding to the target parameters, reducing the service frequency of service braking, prolonging the service life of a service brake, and simultaneously reducing the times of operation of a driver on the whole vehicle when the whole vehicle runs down a long slope, thereby reducing the labor intensity of the driver and improving the safety when the whole vehicle runs down the long slope.)

1. An engine braking power control method characterized by comprising:

when a braking control instruction is received, performing initial braking control on the engine according to preset initial parameters, wherein the preset initial parameters are a preset opening degree of an electronic control bleed valve of the supercharger, a preset opening degree of an air inlet throttle valve and preset opening and closing states of a plurality of braking electromagnetic valves in an initial state;

acquiring the driving speed corresponding to each data acquisition point according to a preset time interval;

calculating corresponding target output braking power according to the driving speed corresponding to each data acquisition point;

searching a preset database table according to the target output braking power to obtain a target parameter corresponding to the target output braking power, wherein the target parameter comprises: the opening degree of the electrically controlled air release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves;

and controlling the electrically controlled bleed valve of the supercharger, the air inlet throttle valve and the plurality of brake electromagnetic valves to reach the state corresponding to the target parameter.

2. The method according to claim 1, wherein the calculating of the corresponding target output braking power according to the driving speed corresponding to each data acquisition point comprises:

acquiring the driving speed corresponding to each data acquisition point;

calculating the initial acceleration of the engine according to a first preset formula

calculating the additionally required braking power under the current working condition according to a second preset formula, wherein the second preset formula is

searching the preset database table according to the driving speed corresponding to each data acquisition point to obtain corresponding initial braking power;

and taking the sum of the initial braking power and the braking power additionally required under the current working condition as the target output braking power corresponding to the driving speed corresponding to each data acquisition point.

3. The method of claim 2, further comprising, after controlling the supercharger electronically-controlled bleed valve, the intake throttle valve, and the plurality of brake solenoid valves to a state corresponding to the target parameter:

and when the running state of the engine is detected to be in a deceleration state, correcting the whole vehicle mass to obtain the corrected whole vehicle mass.

4. The method according to claim 3, wherein the correcting the quality of the finished vehicle is specifically:

acquiring a driving speed corresponding to a current data acquisition point;

calculating the deceleration of the engine according to a third predetermined formulaWhere b is the deceleration of the engine, v_cThe driving speed v corresponding to the current data acquisition point_dThe corresponding driving speed t for the next data acquisition point_d-t_cTime increment corresponding to two vehicle speeds;

calculating the quality correction coefficient according to a preset formula

and multiplying the mass correction coefficient by the additionally required braking power under the current working condition to obtain the corrected finished automobile mass.

5. The method of claim 1, further comprising:

and when a brake closing control instruction is received or the condition that the driving speeds corresponding to at least two continuous data acquisition points are equal is detected, the brake power control process is quitted.

6. An engine braking power control system, comprising:

the first processing unit is used for carrying out initial braking control on the engine according to preset initial parameters when a braking control instruction is received, wherein the preset initial parameters are a preset opening degree of an electronic control bleed valve of the supercharger, a preset opening degree of an air inlet throttle valve and preset opening and closing states of a plurality of braking electromagnetic valves in an initial state;

the second processing unit is used for acquiring the driving speed corresponding to each data acquisition point according to a preset time interval;

the third processing unit is used for calculating corresponding target output braking power according to the driving speed corresponding to each data acquisition point;

a fourth processing unit, configured to search a preset database table according to the target output braking power, to obtain a target parameter corresponding to the target output braking power, where the target parameter includes: the opening degree of the electrically controlled air release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves;

and the fifth processing unit is used for controlling the electrically controlled bleed valve of the supercharger, the air inlet throttle valve and the plurality of brake electromagnetic valves to reach the state corresponding to the target parameter.

7. The system according to claim 6, wherein the third processing unit is specifically configured to:

acquiring the driving speed corresponding to each data acquisition point;

calculating the initial acceleration of the engine according to a first preset formulaWhere a is the initial acceleration of the engine, v_aThe driving speed v corresponding to the preset data acquisition point_bThe driving speed, t, corresponding to the next data acquisition point_b-t_aTime increment corresponding to two vehicle speeds;

calculating the additionally required braking power under the current working condition according to a second preset formula, wherein the second preset formula is

searching the preset database table according to the driving speed corresponding to each data acquisition point to obtain corresponding initial braking power;

and taking the sum of the initial braking power and the braking power additionally required under the current working condition as the target output braking power corresponding to the driving speed corresponding to each data acquisition point.

8. The system of claim 7, wherein the fifth processing unit is further configured to:

and when the running state of the engine is detected to be in a deceleration state, correcting the whole vehicle mass to obtain the corrected whole vehicle mass.

9. The system according to claim 8, wherein the fifth processing unit is specifically configured to:

acquiring a driving speed corresponding to a current data acquisition point;

calculating the deceleration of the engine according to a third predetermined formula

calculating the quality correction coefficient according to a preset formula

and multiplying the mass correction coefficient by the additionally required braking power under the current working condition to obtain the corrected finished automobile mass.

10. The system of claim 6, further comprising:

and the sixth processing unit is used for exiting the brake power control process when a brake closing control instruction is received or the condition that the driving speeds corresponding to at least two continuous data acquisition points are equal is detected.

Technical Field

The application relates to the field of engine auxiliary brake control, in particular to an engine brake power control method and system.

Background

At present, when most of the whole vehicles run on a full load or a heavy load downhill, the engine auxiliary brake must be started on a certain gear, the vehicle speed is controlled by combining intermittent service braking, when the engine auxiliary brake is used, a driver needs to select a proper brake gear according to conditions such as road conditions and vehicle loads to complete the whole vehicle brake, and the brake gear is generally divided into two gears: brake high and brake low.

The existing control flow when the whole vehicle is downhill is as follows: when the whole vehicle starts to go downhill, a driver is required to select a gear of a gearbox according to the current vehicle speed, the driver puts the gear into a certain gear, and after the proper set vehicle speed is reached, the driver presses a brake switch of the whole vehicle to select a brake gear (brake high gear or brake low gear): when a high gear (or a low gear) is selected for braking, the ECU controls to open all the braking electromagnetic valves (or part of the braking electromagnetic valves) to carry out auxiliary braking of the engine, if the downhill speed of the engine is increased too fast in the downhill process, the brake power needs to be increased when the currently output brake power cannot meet the requirement of braking the whole vehicle, and at the moment, the problem that the vehicle speed is increased too fast needs to be solved by switching the brake high gear to the brake low gear (or switching the brake low gear to the brake high gear) or using the service brake, so that the operation not only increases the service frequency of the service brake and reduces the service life of the service brake, and when the service brake is frequently used, the brake is easily overheated, so that the braking efficiency is greatly reduced, the braking effect is influenced, the labor intensity of a driver is increased, and the safety of the whole vehicle in long-slope driving is influenced.

Disclosure of Invention

The application provides an engine braking power control method and system, and aims to reduce the service frequency of service braking, reduce the service life of a service brake, greatly reduce the braking efficiency due to easy overheating when the service brake is frequently used, influence the braking effect, and reduce the operation times of a driver on a whole vehicle when the whole vehicle runs on a long slope, thereby reducing the labor intensity of the driver and improving the safety of the whole vehicle when the whole vehicle runs on the long slope.

In order to achieve the above object, the present application provides the following technical solutions:

an engine braking power control method comprising:

when a braking control instruction is received, performing initial braking control on the engine according to preset initial parameters, wherein the preset initial parameters are a preset opening degree of an electronic control bleed valve of the supercharger, a preset opening degree of an air inlet throttle valve and preset opening and closing states of a plurality of braking electromagnetic valves in an initial state;

acquiring the driving speed corresponding to each data acquisition point according to a preset time interval;

calculating corresponding target output braking power according to the driving speed corresponding to each data acquisition point;

searching a preset database table according to the target output braking power to obtain a target parameter corresponding to the target output braking power, wherein the target parameter comprises: the opening degree of the electrically controlled air release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves;

and controlling the electrically controlled bleed valve of the supercharger, the air inlet throttle valve and the plurality of brake electromagnetic valves to reach the state corresponding to the target parameter.

Preferably, the calculating the corresponding target output braking power according to the driving speed corresponding to each data acquisition point specifically includes:

acquiring the driving speed corresponding to each data acquisition point;

calculating the initial value of the engine according to a first preset formulaThe initial acceleration is given by the first predetermined formulaWhere a is the initial acceleration of the engine, v_aThe driving speed v corresponding to the preset data acquisition point_bThe driving speed, t, corresponding to the next data acquisition point_b-t_aTime increment corresponding to two vehicle speeds;

calculating the additionally required braking power under the current working condition according to a second preset formula, wherein the second preset formula is

Wherein, Δ p is the additionally required braking power under the current working condition, and m is the vehicle mass;

searching the preset database table according to the driving speed corresponding to each data acquisition point to obtain corresponding initial braking power;

and taking the sum of the initial braking power and the braking power additionally required under the current working condition as the target output braking power corresponding to the driving speed corresponding to each data acquisition point.

Preferably, after controlling the electrically controlled purge valve of the supercharger, the intake throttle valve and the plurality of brake solenoid valves to reach the state corresponding to the target parameter, the method further includes:

and when the running state of the engine is detected to be in a deceleration state, correcting the whole vehicle mass to obtain the corrected whole vehicle mass.

Preferably, the correcting the whole vehicle mass specifically comprises:

acquiring a driving speed corresponding to a current data acquisition point;

calculating the deceleration of the engine according to a third predetermined formula

Where b is the deceleration of the engine, v_cFor the travelling crane corresponding to the current data acquisition pointVehicle speed v_dThe corresponding driving speed t for the next data acquisition point_d-t_cTime increment corresponding to two vehicle speeds;

calculating the quality correction coefficient according to a preset formulaWherein x is a mass correction coefficient;

and multiplying the mass correction coefficient by the additionally required braking power under the current working condition to obtain the corrected finished automobile mass.

Preferably, the engine braking power control method further includes:

and when a brake closing control instruction is received or the condition that the driving speeds corresponding to at least two continuous data acquisition points are equal is detected, the brake power control process is quitted.

An engine braking power control system comprising:

the first processing unit is used for carrying out initial braking control on the engine according to preset initial parameters when a braking control instruction is received, wherein the preset initial parameters are a preset opening degree of an electronic control bleed valve of the supercharger, a preset opening degree of an air inlet throttle valve and preset opening and closing states of a plurality of braking electromagnetic valves in an initial state;

the second processing unit is used for acquiring the driving speed corresponding to each data acquisition point according to a preset time interval;

the third processing unit is used for calculating corresponding target output braking power according to the driving speed corresponding to each data acquisition point;

a fourth processing unit, configured to search a preset database table according to the target output braking power, to obtain a target parameter corresponding to the target output braking power, where the target parameter includes: the opening degree of the electrically controlled air release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves;

and the fifth processing unit is used for controlling the electrically controlled bleed valve of the supercharger, the air inlet throttle valve and the plurality of brake electromagnetic valves to reach the state corresponding to the target parameter.

Preferably, the third processing unit is specifically configured to:

acquiring the driving speed corresponding to each data acquisition point;

calculating the initial acceleration of the engine according to a first preset formula

Where a is the initial acceleration of the engine, v_aThe driving speed v corresponding to the preset data acquisition point_bThe driving speed, t, corresponding to the next data acquisition point_b-t_aTime increment corresponding to two vehicle speeds;

calculating the additionally required braking power under the current working condition according to a second preset formula, wherein the second preset formula is

Wherein, Δ p is the additionally required braking power under the current working condition, and m is the vehicle mass;

searching the preset database table according to the driving speed corresponding to each data acquisition point to obtain corresponding initial braking power;

and taking the sum of the initial braking power and the braking power additionally required under the current working condition as the target output braking power corresponding to the driving speed corresponding to each data acquisition point.

Preferably, the fifth processing unit is further configured to:

and when the running state of the engine is detected to be in a deceleration state, correcting the whole vehicle mass to obtain the corrected whole vehicle mass.

Preferably, the fifth processing unit is specifically configured to:

acquiring a driving speed corresponding to a current data acquisition point;

calculating the deceleration of the engine according to a third predetermined formulaWhere b is the deceleration of the engine, v_cThe driving speed v corresponding to the current data acquisition point_dThe corresponding driving speed t for the next data acquisition point_d-t_cTime increment corresponding to two vehicle speeds;

calculating the quality correction coefficient according to a preset formula

Wherein x is a mass correction coefficient;

and multiplying the mass correction coefficient by the additionally required braking power under the current working condition to obtain the corrected finished automobile mass.

Preferably, the engine braking power control system further includes:

and the sixth processing unit is used for exiting the brake power control process when a brake closing control instruction is received or the condition that the driving speeds corresponding to at least two continuous data acquisition points are equal is detected.

According to the method and the system for controlling the braking power of the engine, when a braking control instruction is received, initial braking control is firstly carried out on the engine according to preset initial parameters (the preset initial parameters are the preset opening degree of an electric control air release valve of a supercharger, the preset opening degree of an air inlet throttle valve and the preset opening and closing states of a plurality of braking electromagnetic valves in the initial state); then, acquiring the driving speed corresponding to each data acquisition point according to a preset time interval; calculating corresponding target output braking power according to the driving speed corresponding to each data acquisition point; searching a preset database table according to the target output braking power to obtain target parameters corresponding to the target output braking power (the target parameters comprise the opening degree of an electrically controlled release valve of the supercharger, the opening degree of an air inlet throttle valve and the opening and closing states of a plurality of braking electromagnetic valves); and finally, controlling the electrically controlled air release valve, the air inlet throttle valve and the plurality of brake electromagnetic valves of the supercharger to reach the state corresponding to the target parameters, thereby realizing the control of the brake power of the engine.

In the application, when a braking control instruction is received, firstly, initial braking control is carried out on an engine according to preset initial parameters; then, acquiring the driving speed corresponding to each data acquisition point according to a preset time interval; and finally, controlling a supercharger electric control air release valve, an air inlet throttle valve and a plurality of brake solenoid valves to reach a state corresponding to the target parameters, reducing the service frequency of service braking, prolonging the service life of a service brake, and simultaneously reducing the times of operation of a driver on the whole vehicle when the whole vehicle runs down a long slope, thereby reducing the labor intensity of the driver and improving the safety when the whole vehicle runs down the long slope.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a flow chart of a method of controlling engine braking power as disclosed in an embodiment of the present application;

FIG. 2 is a detailed flowchart of the calculation of the target output braking power of the engine based on the current operating vehicle speed as disclosed in the embodiment of the present application;

fig. 3 is a specific flowchart for correcting the overall vehicle quality disclosed in the embodiment of the present application;

fig. 4 is a schematic structural diagram of an engine braking power control system disclosed in an embodiment of the present application.

Detailed Description

The inventor researches and discovers that in the existing whole vehicle brake control system, because the rotating speed and the brake power are in a one-to-one curve relationship under each brake gear, namely, for a certain fixed rotating speed, only two different brake powers are needed by selecting a high gear and a low gear for braking, therefore, in the process of descending a slope of a whole vehicle, the brake gear of the whole vehicle needs to be adjusted for many times or the vehicle brake is adopted, and the speed of the whole vehicle is basically maintained at the set speed according to the speed change condition.

In order to solve the problems, the application provides an engine braking power control method and an engine braking power control system, which are mainly applied to the scene that most of finished automobiles are fully loaded or heavily loaded downhill.

The invention of the present application aims to: the brake power output by the engine can be adjusted by adjusting the opening degree of the electrically controlled air release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves, the service frequency of service braking is reduced, the service life of a service brake is prolonged, and meanwhile, the operation frequency of a driver on the whole vehicle is reduced when the whole vehicle runs on a long slope, so that the labor intensity of the driver is reduced, and the safety of the whole vehicle running on the long slope is improved.

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

As shown in fig. 1, an embodiment of the present application provides a flowchart of an engine braking power control method, which specifically includes the following steps:

s101: when a braking control instruction is received, initial braking control is carried out on the engine according to preset initial parameters, wherein the preset initial parameters are the preset opening degree of the electrically-controlled deflation valve of the supercharger, the preset opening degree of the air inlet throttle valve and the preset opening and closing states of the plurality of braking electromagnetic valves in the initial state.

The auxiliary engine brake button is arranged on the whole vehicle, and during driving, when a driver turns on the auxiliary engine brake button, the auxiliary engine brake function is started, and when the driver turns off the auxiliary engine brake button, the auxiliary engine brake function is turned off.

When the whole vehicle starts to go downhill, a driver presses an engine auxiliary brake button and sends a brake control command to an engine Electronic Control Unit (ECU). When an Electronic Control Unit (ECU) of the engine receives a braking control command, the system performs initial control of braking control, namely: and performing initial braking control on the engine according to preset parameters stored in an Electronic Control Unit (ECU) of the engine. Specifically, the preset parameters stored in the ECU are the preset opening degree of the electronic control bleed valve of the supercharger in the initial state, the preset opening degree of the intake throttle valve, and the preset opening and closing states of the plurality of brake solenoid valves, that is, the preset opening degree of the electronic control bleed valve of the supercharger, the preset opening degree of the intake throttle valve, and the preset opening and closing states of the plurality of brake solenoid valves in the default state.

It should be noted that, in the embodiment of the present application, in a default case, the preset opening degree of the electronic control purge valve of the supercharger is 0.7, where 0.7 represents that the opening degree of the electronic control purge valve of the supercharger is 70%; the preset opening degree of the air inlet throttle valve is 1, wherein 1 represents that the opening degree of the air inlet throttle valve is 100%; the preset open-close state of the plurality of brake solenoid valves is to close one of the plurality of brake solenoid valves.

S102: and acquiring the driving speed corresponding to each data acquisition point according to a preset time interval.

The engine braking power control process comprises a plurality of data acquisition points, wherein each data acquisition point is set according to a preset time interval, is usually set according to a sampling frequency and is generally set to be dozens of milliseconds, and the first data acquisition point of the preset data acquisition points is the first data acquisition point after a driver presses an auxiliary engine braking button.

S103: and calculating corresponding target output braking power according to the driving speed corresponding to each data acquisition point.

Before a driver presses an engine auxiliary brake button, the driver selects a certain proper gearbox gear, at the moment, a plurality of corresponding vehicle speeds are obtained according to a plurality of preset data acquisition points, the vehicle speeds are the vehicle speeds corresponding to the data acquisition points, and corresponding target output brake power is calculated according to the vehicle speeds corresponding to the data acquisition points.

In the embodiment of the present application, the corresponding target output braking power is calculated according to the driving speed corresponding to each data acquisition point according to the following steps, as shown in fig. 2, the corresponding target output braking power is calculated according to the driving speed corresponding to each data acquisition point, which specifically includes the following steps:

s201: and acquiring the driving speed corresponding to each data acquisition point.

S202: an initial acceleration of the engine is calculated according to a first preset formula.

The first predetermined formula is

Where a is the initial acceleration of the engine, v_aVehicle speed, v, corresponding to the current data acquisition point_bVehicle speed, t, for the next data acquisition point_b-t_aFor two vehicle speed increments.

Here, it should be noted that, during a long downhill slope, due to the inertia of the entire vehicle, the vehicle speed v corresponding to the next data acquisition point_bShould be greater than the vehicle speed v corresponding to the current data acquisition point_aT is_b-t_aIs set according to the sampling frequency, and is generally set to several tens of milliseconds.

S203: and calculating the additionally required braking power under the current working condition according to a second preset formula.

The second predetermined formula is

Wherein, Δ p is the system of the additional requirement under the current working conditionThe dynamic power m is the mass of the whole vehicle, and in the embodiment of the application, the whole vehicle is defaulted as a standard load.

S204: and searching the preset database table according to the driving speed corresponding to each data acquisition point to obtain corresponding initial braking power.

S205: and taking the sum of the initial braking power and the additionally required braking power under the current working condition as the target output braking power corresponding to the driving speed corresponding to each data acquisition point.

It should be noted that the driving speed corresponding to each data acquisition point, or the driving speed corresponding to the data acquisition point, may be converted between the driving speed and the driving speed according to a rule preset in the engine electronic control unit ECU, where the conversion between the driving speed and the driving speed belongs to the prior art, and is not described in detail herein.

S104: searching a preset database table according to the target output brake power to obtain a target parameter corresponding to the target output brake power, wherein the target parameter comprises: the opening degree of the electrically controlled air release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves.

The ECU of the engine pre-stores a preset database table calibrated according to standard loads, and the preset database table stores the corresponding opening degree of the electrically controlled release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of a plurality of brake electromagnetic valves under each vehicle speed or rotating speed.

S105: and controlling the electrically controlled air release valve, the air inlet throttle valve and the plurality of brake electromagnetic valves of the supercharger to reach the state corresponding to the target parameters.

It should be noted that, the air intake amount can be increased by increasing the opening of the air intake throttle valve and closing or reducing the opening of the electronic control air bleed valve when the target output braking power exceeds the initial braking power by judging the target output braking power and the initial braking power corresponding to the current data acquisition point, so as to increase the braking power; when the target output braking power is lower than the initial braking power, the air inlet amount is reduced by reducing the development of the air inlet throttle valve and increasing the opening of the electric control air release valve, and then the braking power is reduced.

In the embodiment of the application, the initial braking power can be set to be within a preset range, and the opening degree of the air inlet throttle valve and the opening degree of the electrically-controlled air release valve of the supercharger do not need to be adjusted within the preset range.

S106: and when a brake closing control instruction is received or the condition that the driving speeds corresponding to at least two data acquisition points are equal is detected, the brake power control process is quitted.

When the driver turns off the auxiliary engine brake button, a brake off control command is sent to the electronic engine control unit ECU. And when the electronic control unit ECU of the transmitter receives the command of closing the brake, the brake power control process is quitted.

In addition, when the electronic control unit ECU of the transmitter detects that the driving speeds corresponding to at least two data acquisition points are equal, the whole vehicle is explained to be in the set driving speed, and in this case, the whole vehicle can be controlled to quit the braking power control process.

It should be noted that the above-mentioned vehicle mass m is a default value and is set as a standard load, but the vehicle mass m varies depending on the vehicle load. In order to make the calculated target output brake power closer to the actual output brake power, after controlling the electrically controlled purge valve of the supercharger, the intake throttle valve, and the plurality of brake solenoid valves to reach the state corresponding to the target parameter, the method further includes:

and when the running state of the engine is detected to be in a deceleration state, correcting the whole vehicle mass to obtain the corrected whole vehicle mass.

In the embodiment of the application, if the running state of the engine is detected to be in deceleration, the current output brake power is larger than the calculated target output brake power, in the application, because the whole vehicle mass m is changed, it can be shown that the whole vehicle mass m is smaller in the calculation process, therefore, the whole vehicle mass m needs to be properly corrected to obtain the corrected whole vehicle mass, then the corresponding target output brake power is calculated according to the whole vehicle mass corrected, the corresponding opening degree of the electrically controlled release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves are determined according to a table look-up, and finally, the electrically controlled release valve of the supercharger, the air inlet throttle valve and the plurality of brake electromagnetic valves are controlled to reach the corresponding states of the opening degree of the electrically controlled release valve of the supercharger, the opening degree of the air inlet throttle valve and the, and the output braking power is closer to the actual output braking power.

Specifically, the method corrects the quality of the whole vehicle according to the following steps, as shown in fig. 3, and specifically includes the following steps:

s301: and acquiring the driving speed corresponding to each data acquisition point.

S302: the deceleration of the engine is calculated according to a first preset formula.

The third predetermined formula is

Where b is the deceleration of the engine, v_cThe running speed v corresponding to each data acquisition point_dThe driving speed, t, corresponding to the next data acquisition point_d-t_cFor two vehicle speed increments.

S303: and calculating the quality correction coefficient according to a preset formula.

The predetermined formula isWherein x is a mass correction coefficient.

S304: and multiplying the mass correction coefficient by the additionally required braking power under the current working condition to obtain the corrected mass of the whole vehicle.

According to the engine braking power control method provided by the embodiment of the application, when a braking control command is received, firstly, initial braking control is carried out on an engine according to preset initial parameters; then, acquiring the driving speed corresponding to each data acquisition point according to a preset time interval; and finally, controlling a supercharger electric control air release valve, an air inlet throttle valve and a plurality of brake solenoid valves to reach a state corresponding to the target parameters, reducing the service frequency of service braking, prolonging the service life of a service brake, and simultaneously reducing the times of operation of a driver on the whole vehicle when the whole vehicle runs down a long slope, thereby reducing the labor intensity of the driver and improving the safety when the whole vehicle runs down the long slope.

Referring to fig. 4, based on the method for controlling engine braking power disclosed in the foregoing embodiment, the present embodiment correspondingly discloses an engine braking power control system, which specifically includes: a first processing unit 401, a second processing unit 401, a third processing unit 403, a fourth processing unit 404, a fifth processing unit 405, and a sixth processing unit 406, wherein:

the first processing unit 401 is configured to, when a braking control instruction is received, perform initial braking control on the engine according to preset initial parameters, where the preset initial parameters are a preset opening degree of an electrically controlled purge valve of the supercharger, a preset opening degree of an intake throttle valve, and preset opening and closing states of a plurality of braking electromagnetic valves in an initial state.

The auxiliary engine brake button is arranged on the whole vehicle, and during driving, when a driver turns on the auxiliary engine brake button, the auxiliary engine brake function is started, and when the driver turns off the auxiliary engine brake button, the auxiliary engine brake function is turned off.

When the whole vehicle starts to go downhill, a driver presses an engine auxiliary brake button and sends a brake control command to an engine Electronic Control Unit (ECU). When an Electronic Control Unit (ECU) of the engine receives a braking control command, the system performs initial control of braking control, namely: and performing initial braking control on the engine according to preset parameters stored in an Electronic Control Unit (ECU) of the engine. Specifically, the preset parameters stored in the ECU are the preset opening degree of the electronic control bleed valve of the supercharger in the initial state, the preset opening degree of the intake throttle valve, and the preset opening and closing states of the plurality of brake solenoid valves, that is, the preset opening degree of the electronic control bleed valve of the supercharger, the preset opening degree of the intake throttle valve, and the preset opening and closing states of the plurality of brake solenoid valves in the default state.

It should be noted that, in the embodiment of the present application, in a default case, the preset opening degree of the electronic control purge valve of the supercharger is 0.7, where 0.7 represents that the opening degree of the electronic control purge valve of the supercharger is 70%; the preset opening degree of the air inlet throttle valve is 1, wherein 1 represents that the opening degree of the air inlet throttle valve is 100%; the preset open-close state of the plurality of brake solenoid valves is to close one of the plurality of brake solenoid valves.

And the second processing unit 401 is configured to obtain the driving speed corresponding to each data acquisition point according to a preset time interval.

The engine braking power control process comprises a plurality of data acquisition points, wherein each data acquisition point is set according to a preset time interval, is usually set according to a sampling frequency and is generally set to be dozens of milliseconds, and the first data acquisition point of the preset data acquisition points is the first data acquisition point after a driver presses an auxiliary engine braking button.

And the third processing unit 403 is configured to calculate a corresponding target output braking power according to the driving speed corresponding to each data acquisition point.

Before a driver presses an engine auxiliary brake button, the driver selects a certain proper gearbox gear, at the moment, a plurality of corresponding vehicle speeds are obtained according to a plurality of preset data acquisition points, the vehicle speeds are the vehicle speeds corresponding to the data acquisition points, and corresponding target output brake power is calculated according to the vehicle speeds corresponding to the data acquisition points.

A fourth processing unit 404, configured to search a preset database table according to the target output braking power, to obtain a target parameter corresponding to the target output braking power, where the target parameter includes: the opening degree of the electrically controlled air release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves.

The ECU of the engine pre-stores a preset database table calibrated according to standard loads, and the preset database table stores the corresponding opening degree of the electrically controlled release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of a plurality of brake electromagnetic valves under each vehicle speed or rotating speed.

And a fifth processing unit 405, configured to control the electrically controlled purge valve of the supercharger, the intake throttle valve, and the plurality of brake solenoid valves to reach a state corresponding to the target parameter.

And the sixth processing unit 406 is configured to exit the brake power control process when a brake closing control instruction is received or it is detected that the vehicle speeds corresponding to at least two of the data acquisition points are equal.

It should be noted that, the air intake amount can be increased by increasing the opening of the air intake throttle valve and closing or reducing the opening of the electronic control air bleed valve when the target output braking power exceeds the initial braking power by judging the target output braking power and the initial braking power corresponding to the current data acquisition point, so as to increase the braking power; when the target output braking power is lower than the initial braking power, the air inlet amount is reduced by reducing the development of the air inlet throttle valve and increasing the opening of the electric control air release valve, and then the braking power is reduced.

In the embodiment of the application, the initial braking power can be set to be within a preset range, and the opening degree of the air inlet throttle valve and the opening degree of the electrically-controlled air release valve of the supercharger do not need to be adjusted within the preset range.

Preferably, the third processing unit 403 is specifically configured to:

acquiring the driving speed corresponding to each data acquisition point;

calculating the initial acceleration of the engine according to a first preset formula

Where a is the initial acceleration of the engine, v_aThe driving speed v corresponding to the preset data acquisition point_bThe driving speed, t, corresponding to the next data acquisition point_b-t_aTwo vehicle speed pairsThe corresponding time increment;

calculating the additionally required braking power under the current working condition according to a second preset formula, wherein the second preset formula is

Wherein, Δ p is the additionally required braking power under the current working condition, and m is the vehicle mass;

searching the preset database table according to the driving speed corresponding to each data acquisition point to obtain corresponding initial braking power;

and taking the sum of the initial braking power and the braking power additionally required under the current working condition as the target output braking power corresponding to the driving speed corresponding to each data acquisition point.

Here, it should be noted that, during a long downhill slope, due to the inertia of the entire vehicle, the vehicle speed v corresponding to the next data acquisition point_bShould be greater than the vehicle speed v corresponding to the current data acquisition point_aT is_b-t_aIs set according to the sampling frequency, and is generally set to several tens of milliseconds. In the embodiment of the application, the whole automobile is the standard load by default.

It should be noted that the above-mentioned vehicle mass m is a default value and is set as a standard load, but the vehicle mass m varies depending on the vehicle load. In order to make the calculated target output braking power closer to the actual output braking power, therefore, the fifth processing unit is further configured to:

and when the running state of the engine is detected to be in a deceleration state, correcting the whole vehicle mass to obtain the corrected whole vehicle mass.

In the embodiment of the application, if the running state of the engine is detected to be in deceleration, the current output brake power is larger than the calculated target output brake power, in the application, because the whole vehicle mass m is changed, it can be shown that the whole vehicle mass m is smaller in the calculation process, therefore, the whole vehicle mass m needs to be properly corrected to obtain the corrected whole vehicle mass, then the corresponding target output brake power is calculated according to the whole vehicle mass corrected, the corresponding opening degree of the electrically controlled release valve of the supercharger, the opening degree of the air inlet throttle valve and the opening and closing states of the plurality of brake electromagnetic valves are determined according to a table look-up, and finally, the electrically controlled release valve of the supercharger, the air inlet throttle valve and the plurality of brake electromagnetic valves are controlled to reach the corresponding states of the opening degree of the electrically controlled release valve of the supercharger, the opening degree of the air inlet throttle valve and the, and the output braking power is closer to the actual output braking power.

Preferably, the fifth processing unit is specifically configured to:

acquiring a driving speed corresponding to a current data acquisition point;

calculating the deceleration of the engine according to a third predetermined formula

Where b is the deceleration of the engine, v_cThe driving speed v corresponding to the current data acquisition point_dThe corresponding driving speed t for the next data acquisition point_d-t_cTime increment corresponding to two vehicle speeds;

calculating the quality correction coefficient according to a preset formulaWherein x is a mass correction coefficient;

and multiplying the mass correction coefficient by the additionally required braking power under the current working condition to obtain the corrected finished automobile mass.

The functions described in the method of the embodiment of the present application, if implemented in the form of software functional units and sold or used as independent products, may be stored in a storage medium readable by a computing device. Based on such understanding, part of the contribution to the prior art of the embodiments of the present application or part of the technical solution may be embodied in the form of a software product stored in a storage medium and including several instructions for causing a computing device (which may be a personal computer, a server, a mobile computing device or a network device) to execute all or part of the steps of the method described in the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other various media capable of storing program codes.

The embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same or similar parts among the embodiments are referred to each other.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the application. Thus, the present application is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.