CN117167129A - Control method and system for cooling fan after stopping vehicle engine - Google Patents

Abstract

The application relates to the technical field of vehicle engine control, in particular to a control method and a system for a cooling fan after a vehicle engine is stopped. According to the application, the starting gear and the starting time of the cooling fan are controlled in a grading manner based on the highest water temperature of the shutdown, the fan control parameters are self-learned from the viewpoint of reducing the energy consumption of the electric load, the fan control parameters are dynamically updated, and then the starting gear and the starting time of the cooling fan are controlled based on the updated fan control parameters, so that the electric load is reasonably distributed, the temperature of the cooling liquid of the engine can be effectively reduced, the service life of the engine is prolonged, and the whole energy consumption of the system is reduced.

Description

Control method and system for cooling fan after stopping vehicle engine

Technical Field

The application relates to the technical field of vehicle engine control, in particular to a control method and a system for a cooling fan after a vehicle engine is stopped.

Background

When the engine of a vehicle is stopped, if the temperature of engine coolant (engine water temperature) is too high, the wear of parts of the engine is increased, and when the wear is severe, permanent damage to the engine is caused.

The engine cooling control scheme in the prior art generally adopts a cooling fan to continuously cool the engine, but the prior art does not consider dynamic control according to the real-time performance of a cooling system, and does not balance design from the aspects of protecting the service life of the engine and reducing the energy consumption of an electric load, so that the existing cooling system has low efficiency and higher energy consumption.

Disclosure of Invention

The application aims to solve the technical problems that: aiming at the defects of the prior art, the control method and the system for the cooling fan after the vehicle engine is stopped are provided, so that the temperature of engine cooling liquid can be effectively reduced, the service life of the engine is prolonged, and the whole energy consumption of the system is reduced.

In order to solve the technical problems, the application adopts the following technical scheme:

1. control method of cooling fan after stopping vehicle engine

The application provides a control method of a cooling fan after a vehicle engine is stopped, which comprises a cooling fan grading control method based on the highest water temperature of stopping and a cooling fan control parameter self-learning updating method;

the cooling fan hierarchical control method based on the shutdown highest water temperature comprises the following strategies:

s11, recording and updating the highest water temperature of the cooling liquid after the engine is stopped in real time, and dividing the highest water temperature into a plurality of sections;

s12, acquiring the current atmospheric temperature and the current atmospheric pressure in real time, and dividing the atmospheric temperature and the atmospheric pressure into a plurality of intervals;

s13, determining an initial running gear of the cooling fan according to the interval of the highest water temperature, and determining the initial running time of the cooling fan according to the interval of the atmospheric temperature and the atmospheric pressure;

s14, carrying out hierarchical control on the cooling fan according to the initial running gear and the initial running time.

The method comprises the following steps:

1) When the current highest water temperature is greater than a preset value A, starting a high-speed gear of the fan, wherein the starting time is a preset time T1; recording the working condition under the condition as a first high-speed opening working condition;

2) When the current highest water temperature is not greater than a preset value A and is greater than a preset value B, starting a high-speed gear of the fan, wherein the starting time is a preset time T2; recording the working condition under the condition as a second high-speed opening working condition;

3) When the current highest water temperature is not greater than a preset value B and is greater than a preset value C, starting a low-speed gear of the fan, wherein the starting time is a preset time T3; recording the working condition under the condition as a low-speed opening working condition III;

4) When the current highest water temperature is not greater than a preset value C and is greater than a preset value D, starting a low-speed gear of the fan, wherein the starting time is a preset time T4; recording the working condition under the condition as a low-speed opening working condition IV;

the preset value A is larger than B and larger than C and larger than D, the preset time T1 is larger than T2 and larger than T3 and larger than T4, and the values of the preset value and the preset time are dynamically updated later according to the energy consumption of the electric load.

The cooling fan control parameter self-learning updating method comprises the following strategies:

s21, recording control parameter values of the cooling fan after the engine is stopped each time, judging whether the vehicle mileage under the condition that the control parameters are not updated exceeds a preset mileage, if so, continuing to execute the subsequent steps, and if not, not performing self-learning updating of the control parameters;

s22, recording the working condition of an engine cooling system under the condition that only a cooling fan works after the engine is stopped and system data under the working condition;

wherein, the system operating mode includes: atmospheric temperature, maximum water temperature of the cooling liquid, fan operation gear; the system data includes: the method comprises the steps of fan running time, cooling liquid water temperature after the fan is closed, the difference between the storage battery SOC when the engine is stopped and the fan is closed, and the time difference between when the cooling liquid water temperature reaches a preset water temperature for the first time and when the fan is closed.

S23, when the same system working condition is met again, the operation working condition of the fan is switched, and when the temperature of the cooling liquid reaches the temperature of the cooling liquid after the fan under the same working condition is closed last time, the fan is controlled to stop running, and the difference between the operation time of the fan and the SOC of the storage battery when the engine is stopped and the fan is closed is recorded;

wherein, the operation condition of the switching fan is specifically: if the last time is the first trigger of the high-speed opening working condition, the third trigger of the low-speed opening working condition is adopted; if the last time is the second trigger of the high-speed opening working condition, the fourth trigger of the low-speed opening working condition is adopted; if the last time is the third trigger of the low-speed opening working condition, the first trigger of the high-speed opening working condition is adopted; if the last time is the low-speed opening working condition four trigger, the high-speed opening working condition two trigger is adopted.

S24, comparing the product difference of the rated power of the fan corresponding to the current fan operation gear and the rated power of the fan corresponding to the fan operation gear under the same working condition of the last time and the product difference of the rated power of the fan corresponding to the fan operation gear and the fan operation time, and comparing the SOC difference of the storage battery when the fan is turned off under the same working condition of the two times;

s25, executing a corresponding cooling fan control parameter updating strategy according to fan operation conditions under the same two working conditions, the product difference of the rated power of the fan corresponding to the fan operation gear and the fan operation time and the storage battery SOC difference when the fan is closed.

The method comprises the following steps:

1) When the fan operation condition is the first high-speed opening condition under the same condition last time and the fan operation condition is the third low-speed opening condition:

1.1 If the difference of the SOC of the storage battery when the fan is closed is smaller than the preset difference V1 and the difference of the product of the rated power of the fan and the running time of the fan is larger than the preset difference W1, increasing the preset value A in the cooling fan hierarchical control method by 10% under the same working condition, reducing the preset value C by 5%, and carrying out power-down storage on the updated preset value A and the updated preset value C;

1.2 If the time difference between the first time of the cooling liquid water temperature reaching the preset water temperature and the time of the fan closing under the same working condition is larger than the preset value M1, reducing the preset time T1 in the cooling fan hierarchical control method under the same working condition by 5%, reducing the preset time T3 by 2%, and performing power-down storage on the updated preset time T1 and the updated preset time T3;

1.3 If the time difference between the first time of the cooling liquid water temperature reaching the preset water temperature and the time of the fan closing is not equal to or larger than the preset value M1 and the frequency of the occurrence of the cooling liquid water temperature being larger than the preset water temperature exceeds the preset value CNT under the same working condition, the preset time T1 in the cooling fan grading control method under the same working condition is increased by 3 percent, the preset time T3 is increased by 2 percent, and the updated preset time T1 and the updated preset time T3 are stored in a power-down mode.

2) When the fan operation condition is the high-speed opening condition II under the same condition last time, the fan operation condition is the low-speed opening condition IV:

2.1 If the difference of the SOC of the storage battery when the fan is closed is smaller than the preset difference V2 and the difference of the product of the rated power of the fan and the running time of the fan is larger than the preset difference W2 (W2 is smaller than W1), increasing the preset value B in the cooling fan hierarchical control method under the same working condition at the next time by 5%, reducing the preset value D by 2%, and carrying out power-down storage on the updated preset value B and the updated preset value D;

2.2 If the time difference between the first time of the cooling liquid water temperature reaching the preset water temperature and the time of the fan closing is larger than a preset value M2 (M2 is smaller than M1) under the same working condition for two times, reducing the preset time T2 in the cooling fan hierarchical control method under the same working condition for the next time by 5%, reducing the preset time T4 by 4%, and carrying out power-down storage on the updated preset time T2 and the updated preset time T4;

2.3 If the time difference between the first time of the cooling liquid water temperature reaching the preset water temperature and the time of the fan closing is not equal to or larger than the preset value M2 and the frequency of the occurrence of the cooling liquid water temperature being larger than the preset water temperature exceeds the preset value CNT under the same working condition, the preset time T2 in the cooling fan grading control method under the same working condition is increased by 2 percent, the preset time T4 is increased by 1 percent, and the updated preset time T2 and the updated preset time T4 are stored in a power-down mode.

3) When the fan operation condition is the low-speed opening condition III under the same condition last time, the fan operation condition is the high-speed opening condition one:

3.1 If the difference of the SOC of the storage battery when the fan is closed is smaller than the preset difference V1 and the difference of the product of the rated power of the fan and the running time of the fan is larger than the preset difference W1, increasing the preset value A in the cooling fan hierarchical control method under the same working condition at the next time by 2%, reducing the preset value C by 1%, and carrying out power-down storage on the updated preset value A and the updated preset value C;

3.2 If the time difference between the first time of the cooling liquid water temperature reaching the preset water temperature and the time of the fan closing under the same working condition is larger than the preset value M1, reducing the preset time T1 in the cooling fan hierarchical control method under the same working condition by 4%, reducing the preset time T3 by 2%, and performing power-down storage on the updated preset time T1 and the updated preset time T3;

3.3 If the time difference between the first time of the cooling liquid water temperature reaching the preset water temperature and the time of the fan closing is not equal to or larger than the preset value M1 and the frequency of the occurrence of the cooling liquid water temperature being larger than the preset water temperature exceeds the preset value CNT under the same working condition, the preset time T1 in the cooling fan grading control method under the same working condition is increased by 2%, the preset time T3 is increased by 1%, and the updated preset time T1 and the preset time T3 are stored in a power-down mode.

4) When the fan operation condition is the high-speed opening condition II under the same condition last time, the fan operation condition is the low-speed opening condition IV:

4.1 If the difference of the SOC of the storage battery when the fan is closed is smaller than the preset difference V2 and the difference of the product of the rated power of the fan and the running time of the fan is larger than the preset difference W2, reducing the preset value B in the cooling fan hierarchical control method under the same working condition at the next time by 2%, increasing the preset value D by 1%, and carrying out power-down storage on the updated preset value B and the updated preset value D;

4.2 If the time difference between the first time of the cooling liquid water temperature reaching the preset water temperature and the time of the fan closing under the same working condition is larger than the preset value M2, the preset time T2 and the preset time T4 in the cooling fan hierarchical control method under the same working condition are increased by 0.5%, and the updated preset time T2 and the updated preset time T4 are stored in a power-down mode.

2. Engine cooling fan control system

Based on the same inventive concept, the application also provides an engine cooling fan control system, which is used for realizing the control method, and mainly comprises the following steps: an engine water outlet temperature sensor, an atmospheric temperature sensor (or an atmospheric temperature signal), a vehicle speed sensor (or a vehicle speed signal), a water pump, a thermal management module (comprising an electronic thermostat), a cooling fan, an engine cooling controller and the like.

1) The engine water outlet temperature sensor is used for detecting the temperature of cooling water at the engine water outlet, namely a water temperature sensor for short and detecting the actual water temperature of the engine;

2) An atmospheric temperature sensor or an atmospheric temperature signal, wherein the engine cooling controller is hard-wired to the atmospheric temperature sensor or receives the atmospheric temperature signal through communication such as a network CAN;

3) The engine cooling controller is hard-wired with the vehicle speed sensor or receives the vehicle speed signal through communication such as network CAN;

4) The water pump is used for driving cooling water to circularly flow;

5) The cooling fan is provided with two gears, namely two rotating speeds, and two fixed powers of low speed and high speed, and is used for cooling water flowing through the radiator.

6) And the engine cooling controller is used for receiving and processing data sent by the engine water outlet temperature sensor, the atmospheric temperature sensor, the vehicle speed sensor and the storage battery SOC and correspondingly controlling the engine cooling fan according to the control method.

3. Manual-automatic integrated vehicle

Based on the same inventive concept, the present application also provides an automated manual vehicle provided with the engine cooling fan control system as described above.

Compared with the prior art, the application has the following main advantages:

1. the application provides a control method and a control system for a cooling fan after a vehicle engine is stopped, which are used for controlling the starting gear and the starting time of the cooling fan in a grading manner based on the highest water temperature of the vehicle engine, carrying out dynamic self-learning update on fan control parameters, and then controlling the starting gear and the starting time of the cooling fan based on the updated fan control parameters, so that the whole energy consumption of the system can be reduced while the service life of the engine is prolonged;

2. the application controls the high-speed and low-speed operation of the cooling fan in a grading way through different stop water temperatures, can reasonably distribute the power load on the premise of fully considering the service life of the engine, and effectively reduces the energy consumption required by the operation of the cooling fan;

3. the application provides a self-learning method of fan control parameters, which can dynamically and intelligently control a cooling fan according to the real-time performance of the energy consumption of a cooling system after an engine is stopped, so as to control the optimal energy consumption of the engine in different life cycles in real time.

Drawings

FIG. 1 is an overall flow chart of a method of controlling an engine cooling fan in an embodiment of the present application;

FIG. 2 is a flow chart of a cooling fan hierarchical control method according to an embodiment of the application;

FIG. 3 is a flowchart of a method for self-learning and updating cooling fan control parameters according to an embodiment of the present application;

FIG. 4 is a schematic diagram of an engine cooling fan control system according to an embodiment of the present application.

Detailed Description

The present application will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present application more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the application. In addition, the technical features of the embodiments of the present application described below may be combined with each other as long as they do not collide with each other.

It should be noted that each step/component described in the present application may be split into more steps/components, or two or more steps/components or part of operations of the steps/components may be combined into new steps/components, according to the implementation needs, to achieve the object of the present application.

In a first embodiment, the present embodiment provides a method for controlling a cooling fan after an engine of a vehicle is stopped, and on the premise of ensuring that the service life of the engine is prolonged after the engine is stopped, the overall electrical load energy consumption is reduced as much as possible.

As shown in fig. 1 to 3, the cooling fan control system mainly comprises two parts, wherein the first part is used for controlling the cooling fan on gear (high speed and low speed) and the fan on time in a grading manner based on the highest water temperature of the machine halt, and the second part is used for carrying out the self-learning of the cooling fan control parameters based on the consideration of reducing the electric load energy consumption.

First, the cooling fan on shift (high and low) and the fan on time are controlled in stages based on the shut-down maximum water temperature.

Recording and updating the highest water temperature (called as the highest water temperature for short) after the engine is stopped in real time, and dividing the highest water temperature into a plurality of sections:

1) When the current highest water temperature is greater than a preset value A, starting a high-speed gear of the fan, wherein the starting time is a preset time T1; the operating condition under this condition is recorded as the high speed fan on condition one.

2) When the current highest water temperature is not greater than A and is greater than a preset value B, starting a high-speed gear of the fan, wherein the starting time is a preset time T2; recording the working condition under the condition as a second high-speed fan starting working condition.

3) When the current highest water temperature is not more than B and is more than a preset value C, starting a low-speed gear of the fan, wherein the starting time is a preset time T3; the condition under this condition is recorded as low speed fan on condition three.

4) When the current highest water temperature is not more than C and is more than a preset value D, starting a low-speed gear of the fan, wherein the starting time is a preset time T4; the condition under this condition is recorded as low speed fan on condition four.

The preset value A is greater than B and greater than C is greater than D, the preset value A of the example is 116 ℃, the preset value B is 114 ℃, the preset value C is 112 ℃, the preset value D is 110 ℃, and the preset value is dynamically updated according to the energy consumption of the electric load.

The preset time T1 > T2 > T3 > T4, T1, T2, T3 and T4 depend on the atmospheric temperature and the atmospheric pressure, the higher the atmospheric temperature and the smaller the atmospheric pressure, the longer the water temperature heat dissipation capability, and thus the longer the fan on time thereof. The calibration of the preset time in this example is shown in tables 1 to 4 below, and the preset time value is dynamically updated later according to the electrical load energy consumption.

TABLE 1

TABLE 2

TABLE 3 Table 3

TABLE 4 Table 4

The 4 conditions above determine that the priority is lower and lower, and once the higher priority condition is satisfied, the fan action (fan on gear and on time) under the corresponding condition is restarted, i.e. once condition 1 is not satisfied but condition 2 is satisfied, the fan high gear is started regardless of the previous fan gear, and the on time is restarted for a preset time T2

As can be seen from the above table, the water temperature must be less than the preset value D before the engine fan is stopped (fan stop means that the fan is not on).

And secondly, performing control parameter self-learning based on the consideration of reducing the energy consumption of the electric load.

The method comprises the steps of recording fan control conditions after each shutdown, if the mileage of an un-updated parameter exceeds a preset value (the example takes 2 kilokilometers, the mileage is restarted to be calculated after any parameter is updated, if the mileage does not exceed the preset mileage, parameter self-learning updating is not carried out, the mileage is low, performance gear updating of engine parts is slower, parameter self-learning is not needed too frequently), recording no other electric loads (only a cooling fan is started, no air conditioner and a headlight are started, if other electric loads except the cooling fan are not carried out, parameter self-learning updating is not carried out) after each shutdown, and if the fan is closed, the difference between the temperature of the air after the shutdown, the atmospheric temperature after the shutdown, the highest water temperature after the shutdown, the fan gear (high-speed fan or low-speed fan), the fan opening time after the shutdown, the water temperature after the fan is closed, the difference between the storage battery SOC at the time of engine shutdown and the time of the fan is the storage battery SOC (simply called the difference between the storage battery SOC at the time of shutdown and the time of the fan closing), recording the temperature is equal to the preset value E (the preset value E is equal to the atmospheric temperature plus an upper deviation F, F is the first time when the fan is close to the preset temperature), and if the difference between the temperature at the time of the fan is equal to the preset water temperature and the fan temperature is not equal to the preset time. Wherein the same working condition is characterized by the same air temperature after the shutdown, the same air pressure after the shutdown, the same highest water temperature after the shutdown and the same fan gear (high-speed fan or low-speed fan) after the shutdown.

When the same working condition is met next time, changing the gear of the fan (namely, if the last time is the first trigger of the high-speed fan starting working condition, the last time adopts the third trigger of the low-speed fan starting working condition, if the last time is the second trigger of the high-speed fan starting working condition, the last time adopts the fourth trigger of the low-speed fan starting working condition, the last time adopts the first trigger of the high-speed fan starting working condition, if the last time is the fourth trigger of the low-speed fan starting working condition, the last time adopts the second trigger of the high-speed fan starting working condition), controlling the water temperature to be reduced to the same water temperature after the fan is closed under the last time same working condition, controlling the fan to stop running, recording the fan starting time, and recording the SOC difference of the storage battery from the time when the fan is closed when the fan is stopped.

The fan power rating corresponding to the fan gear in the same working condition at the last time (provided by a fan supplier, the fan power rating is fixed under high-speed operation in the example, the fan power rating is fixed under low-speed operation, and the two kinds of the fan power ratings are different, the fan power rating under high-speed operation is higher than the fan power rating under low-speed operation) and the product of the fan on time are compared with the product of the fan power rating corresponding to the fan gear and the product of the fan on time, and meanwhile, the difference of the SOC of the storage battery from the time of shutdown to the time of fan shutdown under the same working condition is compared.

1) If the fan gear is the first high-speed opening working condition under the same working condition at the last time, the third low-speed fan opening working condition under the same working condition at the last time:

1.1 If the SOC difference is smaller under the same condition twice (the absolute value of the difference between the SOC differences under the same condition twice divided by the SOC difference under the same condition last time is not more than 2%) in this example, but the difference between the fan power and the fan on time is reduced more (the product of the fan power and the fan on time under the same condition last time minus the product of the fan power and the fan on time under the same condition this time), the obtained difference is divided by the product of the fan power and the fan on time under the same condition this time to be larger, and the difference between the fan power and the fan on time is considered to be reduced more), and exceeds the preset value W1 (the example takes 5%), the preset value a under the same condition after the subsequent engine is stopped again is increased (the preset value a of this example is increased to be 1.1 times of the original preset value a). If the previous preset value A is updated, the original preset value A is the preset value after the last updating and storing; if the previous preset value a is not updated, the original preset value a refers to the previously set value, the example is 116 ℃, and the preset value C is reduced (the preset value C of the example is reduced to 0.95 times of the original preset value C, if the previous preset value C is updated, the original preset value C is the preset value after the last update storage; if the previous preset value C is not updated, the previous preset value C refers to the previously set value, and the example is 112 ℃ and the updated values of the preset value A and the preset value C under the same working condition are stored in a power-down mode.

1.2 If the time difference between the moment when the water temperature approaches the preset value E for the first time and the fan closing moment is larger than the preset value M1 (the example exceeds 10 s) under the same working condition, reducing the preset time T1 and the preset time T3 under the same working condition after the subsequent engine is stopped again (the example reduces the preset time T1 to 0.95 times of the original preset time T1, reduces the preset time T3 to 0.98 times of the original preset time T3, and the same is true, the definition of the original preset time T1 and the definition of the original preset time T3 are the same as the original preset value A), and storing the updated values of the preset time T1 and the preset time T3 under the same working condition;

1.3 If the water temperature at the time of turning off the fan is greater than the preset value E, and the number of occurrences (the number of times is calculated as follows: the condition 1 is satisfied, the condition 1.2 is not satisfied, the water temperature at the time of closing the fan is larger than the preset value E, and the times are accumulated once. And when the next re-condition 1 is met, the condition 1.2 is not met, and the water temperature at the time of closing the fan is greater than the preset value E, and then accumulating. Otherwise, the number of times remains unchanged. Specifically, if condition 1 is satisfied and condition 1.2 is satisfied, when the number of times is cleared) exceeds a preset value CNT (30 in this example), then preset times T1 and T3 under the same working condition are increased after the subsequent engine is stopped again (the preset time T1 in this example is increased to 1.03 times of the original preset time T1, the preset time T3 is increased to 1.02 times of the original preset time T3, and similarly, the definitions of the original preset time T1 and the preset time T3 are the same as the original preset value a), and updated values of the preset times T1 and T3 under the same working condition are stored electrically.

2) If the fan gear is the second high-speed opening working condition under the same working condition last time, the fourth low-speed fan opening working condition under the same working condition this time:

2.1 If the SOC difference is smaller under the same condition of two times, but the difference of the product of the fan power and the fan on time is reduced more, the preset value B is increased (the preset value B in this example is increased by 1.05 times of the original preset value B) under the same condition after the subsequent engine is stopped again, if the difference exceeds the preset value W2 (W2 does not exceed W1, and the present example takes 3%). If the previous preset value B is updated, the original preset value B is the preset value after the last updating and storing; if the previous preset value B is not updated, the previous preset value B is the previously set value, the example is 114 ℃) and the preset value D is reduced (the preset value D of the example is reduced to 0.98 times of the previous preset value D, and the definition of the previous preset value D is the same as the previous preset value A), and the updated values of the preset value B and the preset value D under the same working condition are stored in a power-off mode.

2.2 If the time difference between the moment when the water temperature is first close to the preset value E and the fan closing moment is larger than the preset value M2 (the example exceeds 8 s) under the same working condition, reducing the preset time T2 and T4 under the same working condition after the subsequent engine is stopped again (the example reduces the preset time T2 to 0.95 times of the original preset time T2, reduces the preset time T4 to 0.96 times of the original preset time T4, and the same is true, the definition of the original preset time T2 and the definition of the original preset time T4 are the same as the original preset value A), and storing the updated values of the preset time T2 and the preset time T4 under the same working condition;

2.3 If the water temperature at the time of turning off the fan is greater than the preset value E, and the number of occurrences (the number of times is calculated as follows: the condition 2 is satisfied, the condition 2.2 is not satisfied, the water temperature at the time of closing the fan is larger than the preset value E, and the times are accumulated once. And when the next re-condition 2 is met, the condition 2.2 is not met, and the water temperature at the time of closing the fan is greater than the preset value E, and then accumulating. Otherwise, the number of times remains unchanged. Specifically, if condition 2 is satisfied and condition 2.2 is satisfied, the number of times is cleared) exceeds the preset value CNT, then preset times T2 and T4 (the preset time T2 in this example is increased to 1.02 times the original preset time T2, and the preset time T4 is increased to 1.01 times the original preset time T4 after the subsequent engine is stopped again, and similarly, the definition of the original preset time T2 and the preset time T4 is the same as the original preset value a), and updated values of the preset times T2 and T4 under the same working condition are stored electrically.

3) If the fan gear is the low-speed fan on condition III under the same condition at last time, the fan gear is the high-speed on condition I under the same condition at this time:

3.1 If the SOC difference is smaller under the same condition twice, but the product difference of the fan power and the fan on time is reduced more, exceeding the preset value W1, the preset value a under the same condition after the subsequent engine is stopped again is reduced (the preset value a in this example is reduced to 0.98 times of the original preset value a). If the previous preset value A is updated, the original preset value A is the preset value after the last updating and storing; if the previous preset value A has not been updated, the preset value A refers to the previously set value, in this example 116℃), and the preset value C increases (in this example the preset value C decreases by a factor of 0.99 times the original preset value A. If the previous preset value C is updated, the original preset value C is the preset value after the last updating and storing; if the previous preset value C is not updated, the previous preset value C refers to the previously set value, the example is 112 ℃, and the updated values of the preset values A and C under the same working condition are stored in a power-down mode;

3.2 If the time difference between the time when the water temperature is first close to the preset value E and the fan closing time is larger than the preset value M1, the preset time T1 and the preset time T3 under the same working condition are reduced after the subsequent engine is stopped again (the preset time T1 in the example is reduced to 0.96 times of the original preset time T1, the preset time T3 is reduced to 0.98 times of the original preset time T3, and the same is true, the definition of the original preset time T1 and the preset time T3 is the same as the original preset value A), and the updated values of the preset time T1 and the preset time T3 under the same working condition are stored in a power-down mode

3.3 If the water temperature at the time of turning off the fan is greater than the preset value E, and the number of occurrences (the number of times is calculated as follows: the condition 3 is satisfied, the condition 3.2 is not satisfied, the water temperature at the time of closing the fan is larger than the preset value E, and the times are accumulated once. And when the next re-condition 3 is met, the condition 3.2 is not met, and the water temperature at the time of closing the fan is greater than the preset value E, and then accumulating. Otherwise, the number of times remains unchanged. Specifically, if condition 3 is satisfied and condition 3.2 is satisfied, the number of times is cleared) exceeds the preset value CNT, then preset times T1 and T3 (the preset time T1 in this example is increased to 1.02 times of the original preset time T1, the preset time T3 is increased to 1.01 times of the original preset time T3 after the subsequent engine is stopped again, and similarly, the definition of the original preset time T1 and the preset time T3 is the same as the original preset value a), and updated values of the preset times T1 and T3 under the same working condition are stored electrically.

4) If the last fan gear is the fourth low-speed fan starting condition, the first high-speed starting condition is the second high-speed starting condition:

4.1 If the difference of the SOC is smaller for two times, but the difference of the product of the fan power and the fan on time is reduced more, exceeding the preset value W2, the preset value B is reduced (the preset value B in this example is reduced to 0.98 times of the original preset value B) under the same working condition after the subsequent engine is stopped again. If the previous preset value B is updated, the original preset value B is the preset value after the last updating and storing; if the previous preset value B is not updated, the original preset value B refers to the previously set value, the example is 114 ℃ and the preset value D is increased (the preset value D of the example is increased to 1.01 times of the original preset value D, and the definition of the original preset value D is the same as that of the original preset value A), and the preset value B and the updated value D of the preset value D are stored in a power-off mode under the same working condition;

4.2 If the time difference between the time when the water temperature is first close to the preset value E and the fan closing time is larger than the preset value M2, the preset time T2 and the preset time T4 under the same working condition are reduced after the subsequent engine is stopped again (the preset time T2 of the example is increased to 1.005 times of the original preset time T2, the preset time T4 is increased to 1.005 times of the original preset time T4, and similarly, the definition of the original preset time T2 and the preset time T4 is the same as the original preset value A), and the updated values of the preset time T2 and the preset time T4 under the same working condition are stored in a power-down mode.

After all the above parameters (preset values and preset times) are updated, the updated values are adopted after the subsequent engine is stopped again, and finally, the fan control after the same engine stop is ensured:

the preset value A is more than B and more than C is more than D;

the preset time T1 is more than T2 and more than T3 and more than T4;

if the updated B is greater than the updated A in the same working condition after the engine is stopped, the final B for control is equal to the A, and other parameters are pushed in the same way.

In a second embodiment, based on the same inventive concept, the present embodiment further provides an engine cooling fan control system, configured to implement the control method as described above, as shown in fig. 4, mainly including: an engine water outlet temperature sensor, an atmospheric temperature sensor (or an atmospheric temperature signal), a vehicle speed sensor (or a vehicle speed signal), a water pump, a thermal management module (comprising an electronic thermostat), a cooling fan and an engine cooling controller.

1) The engine water outlet temperature sensor is used for detecting the temperature of cooling water at the engine water outlet, namely a water temperature sensor for short and detecting the actual water temperature of the engine;

2) An atmospheric temperature sensor or an atmospheric temperature signal, wherein the engine cooling controller is hard-wired to the atmospheric temperature sensor or receives the atmospheric temperature signal through communication such as a network CAN;

3) The engine cooling controller is hard-wired with the vehicle speed sensor or receives the vehicle speed signal through communication such as network CAN;

4) The water pump is used for driving cooling water to circularly flow;

5) The cooling fan is provided with two gears, namely two rotating speeds, and two fixed powers of low speed and high speed, and is used for cooling water flowing through the radiator.

6) And the engine cooling controller is used for receiving and processing data sent by the engine water outlet temperature sensor, the atmospheric temperature sensor, the vehicle speed sensor and the storage battery SOC and correspondingly controlling the engine cooling fan according to the control method.

In a third embodiment, based on the same inventive concept, the present embodiment also provides an automated manual vehicle having the engine cooling fan control system as described above installed therein.

Furthermore, the non-detailed description of the present application is the same as or implemented by the prior art.

To sum up:

1. the application provides a control method and a control system for a cooling fan after a vehicle engine is stopped, which are used for controlling the starting gear and the starting time of the cooling fan in a grading manner based on the highest water temperature of the vehicle engine, carrying out dynamic self-learning update on fan control parameters, and then controlling the starting gear and the starting time of the cooling fan based on the updated fan control parameters, so that the whole energy consumption of the system can be reduced while the service life of the engine is prolonged;

2. the application controls the high-speed and low-speed operation of the cooling fan in a grading way through different stop water temperatures, can reasonably distribute the power load on the premise of fully considering the service life of the engine, and effectively reduces the energy consumption required by the operation of the cooling fan;

3. the application provides a self-learning method of fan control parameters, which can dynamically and intelligently control a cooling fan according to the real-time performance of the energy consumption of a cooling system after an engine is stopped, so as to control the optimal energy consumption of the engine in different life cycles in real time.

It will be readily appreciated by those skilled in the art that the foregoing description is merely a preferred embodiment of the application and is not intended to limit the application, but any modifications, equivalents, improvements or alternatives falling within the spirit and principles of the application are intended to be included within the scope of the application.

Claims (10)

1. A control method of a cooling fan after a vehicle engine is stopped is characterized by comprising a cooling fan grading control method based on the highest water temperature of stopping and a cooling fan control parameter self-learning updating method;

the cooling fan hierarchical control method based on the shutdown highest water temperature comprises the following strategies:

recording and updating the highest water temperature of the cooling liquid after the engine is stopped in real time, and dividing the highest water temperature into a plurality of sections;

acquiring the current atmospheric temperature and the current atmospheric pressure in real time, and dividing the atmospheric temperature and the atmospheric pressure into a plurality of intervals;

determining an initial running gear of the cooling fan according to the highest water temperature interval, and determining initial running time of the cooling fan according to the atmospheric temperature and atmospheric pressure interval;

and carrying out hierarchical control on the cooling fan based on the initial operation gear and the initial operation time.

2. The method for controlling a cooling fan after an engine of a vehicle is stopped according to claim 1, wherein the method for self-learning updating of the cooling fan control parameter comprises the following strategies:

recording control parameter values of the cooling fan after the engine is stopped every time, judging whether the mileage of the vehicle under the condition that the control parameters are not updated exceeds a preset mileage, if yes, recording the working condition of the engine cooling system under the condition that only the cooling fan works after the engine is stopped and system data under the working condition;

when the same system working condition is met again, the operation working condition of the fan is switched, and when the temperature of the cooling liquid reaches the temperature of the cooling liquid after the fan under the same working condition is closed last time, the fan is controlled to stop running, and the difference between the operation time of the fan and the SOC of the storage battery when the engine is stopped and the fan is closed is recorded;

comparing the product difference of the rated power of the fan corresponding to the current fan operation gear and the product difference of the rated power of the fan corresponding to the fan operation gear and the fan operation time under the same working condition of the last time, and comparing the SOC difference of the storage battery when the fan is turned off under the same working condition of the two times;

and executing a corresponding cooling fan control parameter updating strategy according to the fan operation working condition under the same working condition twice, the product difference of the rated power of the fan corresponding to the fan operation gear and the fan operation time and the storage battery SOC difference when the fan is closed.

3. The method for controlling a cooling fan after an engine of a vehicle is stopped according to claim 2, wherein the step control of the cooling fan is performed as follows:

when the current highest water temperature is greater than a preset value A, starting a high-speed gear of the fan, wherein the starting time is a preset time T1; recording the working condition under the condition as a first high-speed opening working condition;

when the current highest water temperature is not greater than a preset value A and is greater than a preset value B, starting a high-speed gear of the fan, wherein the starting time is a preset time T2; recording the working condition under the condition as a second high-speed opening working condition;

when the current highest water temperature is not greater than a preset value B and is greater than a preset value C, starting a low-speed gear of the fan, wherein the starting time is a preset time T3; recording the working condition under the condition as a low-speed opening working condition III;

when the current highest water temperature is not greater than a preset value C and is greater than a preset value D, starting a low-speed gear of the fan, wherein the starting time is a preset time T4; the operating condition under this condition is recorded as low-speed opening operating condition four.

4. The method for controlling a cooling fan after an engine of a vehicle is stopped according to claim 2, wherein the system conditions include: atmospheric temperature, maximum water temperature of the cooling liquid, fan operation gear;

the system data includes: the method comprises the steps of fan running time, cooling liquid water temperature after the fan is closed, the difference between the storage battery SOC when the engine is stopped and the fan is closed, and the time difference between when the cooling liquid water temperature reaches a preset water temperature for the first time and when the fan is closed.

5. A control method of a cooling fan after a vehicle engine stop according to claim 3, wherein the switching fan operation condition is specifically as follows:

if the last time is the first trigger of the high-speed opening working condition, the third trigger of the low-speed opening working condition is adopted; if the last time is the second trigger of the high-speed opening working condition, the fourth trigger of the low-speed opening working condition is adopted; if the last time is the third trigger of the low-speed opening working condition, the first trigger of the high-speed opening working condition is adopted; if the last time is the low-speed opening working condition four trigger, the high-speed opening working condition two trigger is adopted.

6. The method for controlling a cooling fan after an engine stop of a vehicle according to claim 4, wherein the executing of the corresponding cooling fan control parameter updating strategy is specifically as follows:

if the difference of the storage battery SOC when the fan is closed is smaller than a preset difference V and the difference of the product of the rated power of the fan and the running time of the fan is larger than a preset difference W, increasing preset ratio of preset values A and B in the cooling fan hierarchical control method under the same working condition, decreasing preset ratio of preset values C and D, and performing power-down storage on the updated preset value A, B, C, D;

if the time difference between the first time of the cooling liquid water temperature reaching the preset water temperature and the time of the fan closing under the same working condition is larger than the preset value M, the preset time T1-T4 in the cooling fan hierarchical control method under the same working condition is reduced by a preset proportion, and the updated preset time T1-T4 is stored in a power-down mode.

7. The method according to claim 6, wherein if the time difference between when the cooling liquid water temperature reaches the preset water temperature for the first time and when the fan is turned off is not equal to or greater than a preset value M and the number of times when the cooling liquid water temperature exceeds the preset water temperature exceeds a preset value CNT in two identical conditions, the preset time T1 to T4 in the cooling fan hierarchical control method in the next identical condition is increased by a preset proportion, and the updated preset time T1 to T4 is stored in a power-down manner.

8. An engine cooling fan control system for implementing the control method according to any one of claims 1 to 7, characterized by comprising:

the engine water outlet temperature sensor is used for detecting the temperature of cooling water at the engine water outlet;

the atmospheric temperature sensor is used for acquiring an atmospheric temperature signal;

the vehicle speed sensor is used for acquiring a vehicle speed signal;

the water pump is used for driving cooling water to circularly flow;

a cooling fan provided with two power modes of low speed and high speed for cooling the cooling water flowing through the radiator;

an engine cooling controller for receiving and processing data sent from an engine water outlet temperature sensor, an atmospheric temperature sensor, a vehicle speed sensor, and a battery SOC, and for controlling an engine cooling fan accordingly according to the control method according to any one of claims 1 to 7.

9. A non-transitory readable storage medium having stored thereon a program which, when executed by an engine cooling fan control system, implements the control method according to any one of claims 1 to 7.

10. An automated manual vehicle, characterized by: comprising the engine cooling fan control system of claim 8.