CN107539064B

CN107539064B - Automobile air conditioner ambient temperature judging system

Info

Publication number: CN107539064B
Application number: CN201711035450.4A
Authority: CN
Inventors: 陈兴富
Original assignee: Chongqing Changan Automobile Co Ltd
Current assignee: Chongqing Changan Automobile Co Ltd
Priority date: 2017-10-30
Filing date: 2017-10-30
Publication date: 2020-07-10
Anticipated expiration: 2037-10-30
Also published as: CN107539064A

Abstract

The invention discloses an automobile air conditioner ambient temperature judgment system which can stably run for a section when a vehicle keeps low speedAfter the time, the air conditioner controller keeps the ambient temperature value to eliminate T₁And T₂Two factors, wherein T₁The temperature rise increment of the temperature value of the environmental temperature signal sensor caused by the heat radiation of the engine room when the engine is in the small circulation, T₂And (4) further temperature rise increment of the temperature value of the ambient temperature signal sensor by the radiator after the engine is opened for a large cycle. The interference of large circulation and small circulation of the engine to the ambient temperature sensor can be effectively eliminated by ensuring the tested ambient temperature value, the testing precision is ensured, and the control accuracy of intelligent opening, closing and the like of the air conditioner controller is improved.

Description

Automobile air conditioner ambient temperature judging system

Technical Field

The invention relates to the field of automobile air conditioner control, in particular to an automobile air conditioner ambient temperature judgment system.

Background

An ambient temperature signal sensor for obtaining an ambient temperature outside a vehicle in an automotive air conditioner is generally installed on an intake grill in front of an engine radiator at a distance of only ten and several centimeters from a surface of the engine radiator. When the vehicle runs at idle speed or low speed, the air flow rate at the ambient temperature sensor is low, and heat emitted by an engine or a radiator is easy to radiate and influence the ambient temperature signal sensor, so that the collected temperature is much higher than the actual ambient temperature.

In the prior art, when a vehicle runs at a high speed or an engine is in a cold state, the temperature acquired by an ambient temperature signal sensor is directly used as the ambient temperature, but when the vehicle runs at a low speed or idles, the ambient temperature value processed by software at the idling speed or at the low speed is greatly deviated from the actual ambient temperature value due to the fact that the ambient temperature signal sensor is influenced by heat radiation of a radiator and the acquired temperature value is higher, so that an error is further brought to an air conditioner automatic control function of an air conditioner controller, and the driving comfort of passengers is poor.

Disclosure of Invention

The invention discloses an automobile air conditioner ambient temperature judgment system, which solves the problem that a large deviation exists between an ambient temperature value acquired by an ambient temperature signal sensor and an actual ambient temperature value when an automobile runs at idle speed or low speed, and carries out thermal interference correction on the interference of engine heat radiation.

The invention discloses a system for judging the ambient temperature of an automobile air conditioner, which comprises: the system comprises an engine water temperature signal sensor, an environment temperature signal sensor, a vehicle speed sensor and an air conditioner controller; the method comprises the following steps:

step 1) after the engine is powered on, the vehicle speed sensor judges the current vehicle speed state,

such as from a high vehicle number to a low vehicle speedA set time T of state₀Step 2) is entered;

if the vehicle enters the low vehicle speed state from the high vehicle speed for more than the set time T₀Entering step 3);

step 2), setting an ambient temperature value Tamb by the air conditioner controller as follows: when the high vehicle speed is reduced to the low vehicle speed state, the ambient temperature value T is acquired by the ambient temperature signal sensor under the high vehicle speed state_{n high speed transients}；

Step 3) if the engine keeps running, the air conditioner controller sets an environmental temperature value Tamb equal to T_n-T₁-T₂Wherein

T_nThe ambient temperature value is acquired by an ambient temperature signal sensor;

T₁when an engine water temperature signal sensor detects that an engine is in a small cycle, the heat radiation of an engine room increases the temperature rise increment of the temperature value of an environment temperature signal sensor;

T₂comprises the following steps: and after the engine water temperature signal sensor detects that the engine is opened in a large cycle, the radiator increases the temperature rise of the temperature value of the environment temperature signal sensor.

Further, T₁The following settings were used:

T_w	T_w1	T_w2	...	T_wn
					T₁	T₁₁	T₁₂	...	T_1n

T₁comprises the following steps: the engine water temperature signal sensor records a group of gradually-increased engine water temperatures T from a cold machine to a large cycle before the engine is opened during a small cycle of the engine_w1,T_w2,...,T_wnUnder the condition, the environment temperature signal sensor collects the environment temperature value

T_{n small cycles}And (4) temperature rise increment relative to the external real environment temperature.

Further, T2 is a temperature value T collected by the environment temperature signal sensor after the large circulation is opened_{After n major cycles}Temperature value T collected by ambient temperature signal sensor at the moment of opening of large cycle_{n major cycles of the instant}Increase in temperature rise.

Further, the high vehicle speed state is set to a state in which the vehicle speed is greater than 15 kph; the low vehicle speed state is set to a state in which the number of vehicles is less than 5kph or an engine idle state.

The beneficial technical effects of the invention are as follows:

1) in the initial stage of reducing the vehicle from high speed to low speed, the air conditioner controller keeps the environmental temperature value as follows: the ambient temperature value T collected by the ambient temperature signal sensor at the moment when the high vehicle speed is reduced to the low vehicle speed state_{n high speed transients}And the influence of the rapid temperature rise of the air around the radiator on the temperature value collected by the ambient temperature signal sensor after the vehicle speed is suddenly reduced is avoided.

2) After the vehicle keeps running at low speed for a period of stable time, the air conditioner controller keeps the ambient temperature value to eliminate T₁And T₂Two factors, wherein T₁The temperature rise increment of the temperature value of the environmental temperature signal sensor caused by the heat radiation of the engine room when the engine is in the small circulation, T₂And (4) further temperature rise increment of the temperature value of the ambient temperature signal sensor by the radiator after the engine is opened for a large cycle. Can effectively protectThe tested ambient temperature value is proved to eliminate the interference of large circulation and small circulation of the engine to the ambient temperature sensor, so that the testing precision is ensured, and the control accuracy of intelligent opening, closing and the like of the air conditioner controller is improved.

Drawings

Fig. 1 is a flow chart of a system for judging the ambient temperature of an automobile air conditioner.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1, the ambient temperature judgment system of the automotive air conditioner comprises an engine water temperature signal sensor, an ambient temperature signal sensor, a vehicle speed sensor and an air conditioner controller; the method comprises the following steps:

a set time T for entering a low speed state from a high speed₀(e.g., 5 minutes), and entering the step 2);

the high vehicle speed state may be set to a state in which the vehicle speed is greater than 15 kph; the low vehicle speed state may be set to a state in which the number of vehicles is less than 5kph or an engine idle state.

Step 2), setting an ambient temperature value Tamb by the air conditioner controller as follows: when the high vehicle speed is reduced to the low vehicle speed state, the ambient temperature value T is acquired by the ambient temperature signal sensor under the high vehicle speed state_{n high speed transients}(ii) a In a short time from high speed to low speed, the windward of the vehicle is reduced, the heat dissipation speed of the radiator is reduced, the temperature of the air around the radiator rises quickly, so that the temperature value acquired by the environment temperature sensor can cause a heat radiation effect, and the error between the temperature value acquired by the environment temperature sensor and the real environment temperature is larger.

Step 3) if the engine keeps running, the air conditioner controller sets an environment temperature value Tamb as Tn-T1-T2, wherein

T₁The following can be set:

T_w(℃)	55	65	80	95
					T₁(℃)	0	5	11	12

T₁comprises the following steps: the engine water temperature signal sensor records a group of engine water temperatures T from a cold machine to a large cycle before the engine is opened during the small cycle of the engine_WThe ambient temperature signal sensor collects ambient temperature values at 55, 65, 80 and 95 DEG C

T₂Comprises the following steps: engine water temperature signal sensor detects engine large cycle beatingAfter the temperature sensor is started, the radiator increases the temperature of the ambient temperature signal sensor.

Claims

1. Vehicle air conditioner ambient temperature judges system, its characterized in that: the system comprises an engine water temperature signal sensor, an environment temperature signal sensor, a vehicle speed sensor and an air conditioner controller; the method comprises the following steps:

for a set time T, e.g. from a high vehicle speed into a low vehicle speed state₀Step 2) is entered;

2. The ambient temperature determination system for an air conditioner of a vehicle according to claim 1, wherein: t is₁The following settings were used:

T_w T_w1 T_w2 ... T_wn T₁ T₁₁ T₁₂ ... T_1n

3. The ambient temperature determination system for an air conditioner of a vehicle according to claim 2, wherein: t2 is temperature value T collected by environment temperature signal sensor after large circulation is opened_{After n major cycles}Temperature value T collected by ambient temperature signal sensor at the moment of opening of large cycle_{n major cycles of the instant}Increase in temperature rise.

4. The automotive air-conditioning ambient temperature determination system according to any one of claims 1 to 3, characterized in that: the high vehicle speed state is set to a state in which the vehicle speed is greater than 15 kph; the low vehicle speed state is set to a state in which the number of vehicles is less than 5kph or an engine idle state.