An electric vehicle air conditioner safety energy-saving control method

Abstract

The present application relates to the field of intelligent control of automobile, in particular to a kind of electric vehicle air conditioner safety energy-saving control method.The present application is installed on the temperature and humidity sensor or all-in-one sensor technology of front windshield.According to the temperature of outside environment, the temperature of inside glass surface, the relative humidity of inside air, confirm the fogging risk level;And based on the fogging risk level, execute inside air conditioner control operation.The present application can optimize air conditioning system energy consumption under the premise of ensuring safe vision, can realize the energy-saving management of fine and safe thermal management control system.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of intelligent control of automobiles, in particular to a kind of electric vehicle air conditioner safety energy-saving control method. BACKGROUND

[0002] The cruising range of new energy vehicles, especially pure electric passenger cars, has always been the focus of customers, and even the primary selection factor for purchasing a car. The automobile air conditioning system is one of the three small electric vehicles of electric vehicles, and the energy consumption of the air conditioning system is the second in pure electric vehicles. The PTC heater and electric compressor are the main energy consumption parts of the air conditioning system. The heat source for passenger compartment heating mainly comes from the PTC heater, and the power required to maintain the thermal comfort of the passenger compartment is generally about 2 kW, which has high energy consumption; 1 kW is required for a heat pump system. One of the methods to prevent fogging is to increase the proportion of outside circulating fresh air, or even full outside circulating fresh air, to avoid the condensation of air with relatively high temperature and humidity on the glass with relatively low temperature and fogging or frosting. How to optimize the energy consumption of the air conditioning system while ensuring the safety of the field of view is particularly important.

[0003] Currently, there are some air conditioning circulation technologies and windshield temperature and humidity sensor technologies, but there is no fine safety energy-saving thermal management control system combining the two. SUMMARY

[0004] The present application aims to solve the problem of passenger compartment low-temperature heating in new energy vehicles, which requires more air conditioning outside circulating fresh air to enter the air conditioning box to prevent glass fogging and frosting, and the passenger compartment heating energy consumption and heating performance are limited by the high priority of anti-fogging and frosting. A kind of thermal management control system is provided to prevent fogging and frosting with the smallest part of outside circulating fresh air, to maximize the reduction of heating energy consumption and to improve the heating performance, to achieve the best balance of field of view safety, passenger comfort and energy consumption. The specific technical scheme is as follows:

[0005] A kind of electric vehicle air conditioner safety energy-saving control method, a multi-in-one sensor is arranged on the inner side of the front windshield and connected to the controller, the multi-in-one sensor measures the windshield temperature (T-wg), the windshield inner humidity (RH-in) and the windshield inner temperature (T-in); The control method is carried out according to the following steps:

[0006] Step 1, based on the indoor humidity (RH-in) and the indoor temperature (T-in), the indoor air dew point temperature (Td) is obtained;

[0007] Step 2, based on the windshield temperature (T-wg) and the indoor air dew point temperature (Td), the fogging temperature difference (ΔT) is calculated;

[0008] Step 3, confirm the fogging risk level, divided into L0, L1, L2, L3, L4 five levels;

[0009] Step 4, according to the fogging risk level, execute air conditioning mode adjustment.

[0010] Further, the ΔT=T-wg-Td in step 2.

[0011] Further, step 3, the confirmation mode is as follows: step 31: based on the windshield temperature T-wg, the correction coefficient k is confirmed, the correction coefficient takes the value: windshield temperature-20℃~-10℃, k is 0.5; -10℃~10℃, k is 0.3; 10℃~20℃, k is 0.6; step 32, calculate the fogging temperature difference threshold T=ΔT×k; step 33, according to the fogging temperature difference threshold T, confirm the fogging risk level, the confirmation range is: T>14℃ is L0 level, 14℃~12℃ is L1 level, 12℃~5℃ is L2 level, 5℃~3℃ is L3 level, T<3℃ is L4 level.

[0012] Further, in step 4, the air conditioning mode adjustment mode is as follows:

[0013] L0 has no fogging risk, and the air conditioner does not change the existing running state;

[0014] L1 is switched to external circulation;

[0015] L2 is switched to external circulation, and the AC is started;

[0016] L3 is switched to external circulation, the AC is started, and the window is blown; the air outlet mode≠blowing face and the air outlet target temperature-environment temperature>-2℃ when triggered;

[0017] L4 is switched to external circulation, the AC is started, and the window is blown; the air outlet target temperature-environment temperature>-2℃ or ambient temperature<20℃ when triggered.

[0018] Further, it also includes step 5, the fogging risk level switching strategy: when the fogging risk level changes from high to low, the risk level needs to be switched after at least 2min, and when the risk level changes from low to high, it is switched immediately.

[0019] The present application is installed on the front windshield by the temperature and humidity sensor or multi-in-one sensor technology. According to the vehicle external environment temperature, the temperature of the vehicle interior glass surface, the relative humidity of the vehicle interior air, the fogging risk level is confirmed; and based on the fogging risk level, the vehicle interior air conditioning control operation is executed. The present application can optimize the energy consumption of the air conditioning system under the premise of ensuring the safe vision, and can realize the fine and safe energy-saving management of the thermal management control system. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1A schematic diagram of the installation of the multi-functional sensor in this invention. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] like Figure 1 As shown, the method of the present invention requires a multi-in-one sensor to be installed on the inside of the windshield and connected to the controller. The multi-in-one sensor measures the windshield temperature (T-wg), the windshield interior humidity (RH-in), and the windshield interior temperature (T-in).

[0023] The specific steps are as follows:

[0024] Step 1: Obtain the dew point temperature (Td) of the air inside the vehicle based on the vehicle's humidity (RH-in) and temperature (T-in).

[0025] The values ​​can be directly obtained from the following table: Ambient temperature, relative humidity, and dew point comparison chart.

[0026]

[0027] Step 2: Calculate the fogging temperature difference (ΔT) based on the windshield temperature (T-wg) and the dew point temperature of the air inside the vehicle (Td).

[0028] Step 3: Confirm the fog risk level, which is divided into five levels: L0, L1, L2, L3, and L4.

[0029] Step 4: Adjust the air conditioning mode according to the fogging risk level.

[0030] Furthermore, in step 2, ΔT = T - wg - Td.

[0031] Further, in step 3, the confirmation method is as follows: Step 31: Confirm the correction coefficient k based on the windshield temperature T-wg. The correction coefficient is set as follows: for windshield temperatures of -20℃ to -10℃, k is 0.5; for -10℃ to 10℃, k is 0.3; for 10℃ to 20℃, k is 0.6; Step 32: Calculate the fogging temperature difference threshold T = ΔT × k; Step 33: Confirm the fogging risk level based on the fogging temperature difference threshold T. The confirmation range is as follows: T > 14℃ is level L0, 14℃ to 12℃ is level L1, 12℃ to 5℃ is level L2, 5℃ to 3℃ is level L3, and T < 3℃ is level L4.

[0032] Further, in step 4, the air conditioning mode adjustment mode is as follows:

[0033] L0 No fogging risk, air conditioner does not change the existing operating state;

[0034] L1 Switch to external circulation;

[0035] L2 Switch to external circulation, AC starts;

[0036] L3 Switch to external circulation, AC starts, blow feet and blow window; outflow mode ≠ blow face and outflow target temperature - ambient temperature > -2℃ when triggered;

[0037] L4 Switch to external circulation, AC starts, blow window; outflow target temperature - ambient temperature > -2℃ or ambient temperature < 20℃ when triggered.

[0038] Further, it also includes step 5, fogging risk level switching strategy: when the fogging risk level changes from high to low, the risk level needs to be low for at least 2 minutes before switching, and when the risk level changes from low to high, it is switched immediately.

[0039] The preferred embodiments of the present patent have been described in detail above, but the present patent is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the present patent.

Claims

1. A method for safe and energy-saving control of air conditioning in electric vehicles, characterized in that: A multi-sensor is arranged on the inner side of the front windshield and connected to a controller, the multi-sensor measures the windshield temperature T-wg, the humidity inside the windshield, i.e. the humidity inside the vehicle RH-in, and the temperature inside the windshield, i.e. the temperature inside the vehicle T-in; the control method is carried out according to the following steps: Step 1: based on the humidity inside the vehicle RH-in and the temperature inside the vehicle T-in, the dew point temperature Td of the air inside the vehicle is obtained; Step 2: based on the windshield temperature T-wg and the dew point temperature Td of the air inside the vehicle, the fogging temperature difference ΔT is calculated, ΔT = T-wg - Td; Step 3: confirm the fogging risk level, divided into L0, L1, L2, L3 and L4 five levels, the confirmation method is as follows: Step 31: based on the windshield temperature T-wg, the correction coefficient k is confirmed, the correction coefficient takes the value: windshield temperature -20℃~-10℃, k is 0.5; -10℃~10℃, k is 0.3; 10℃~20℃, k is 0.6; Step 32: calculate the fogging temperature difference threshold T = ΔT × k; Step 33: according to the fogging temperature difference threshold T, the fogging risk level is confirmed, the confirmation range is: T>14℃ for L0 level, 14℃~12℃ for L1 level, 12℃~5℃ for L2 level, 5℃~3℃ for L3 level, and T<3℃ for L4 level; Step 4: according to the fogging risk level, the air conditioning mode adjustment is executed; the air conditioning mode adjustment method is as follows: L0 has no fogging risk, the air conditioner does not change the existing running state; L1 switches to external circulation; L2 switches to external circulation and starts AC; L3 switches to external circulation, starts AC and blows feet and windows; the outflow mode ≠ blows face and the outflow target temperature-environment temperature >-2℃ triggers; L4 switches to external circulation, starts AC and blows windows; the outflow target temperature-environment temperature >-2℃ or the ambient temperature <20℃ triggers. Step 5: fogging risk level switching strategy: when the fogging risk level changes from high to low, the risk level needs to be switched after at least 2 minutes, and when the risk level changes from low to high, it is switched immediately. ​ 2. The method according to claim 1, wherein the method further comprises: ​

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