A method and device for controlling the heating of a hybrid vehicle

Abstract

The application relates to a hybrid vehicle heating air control method and device, and relates to the technical field of vehicle control. The method comprises the following steps: calculating the heating air abundance of a vehicle cabin air conditioner based on the ambient temperature, the air conditioner target heating temperature, the actual temperature of the vehicle cabin, the air volume gear of the air conditioner blower, the air blowing mode of the air conditioner, the engine water temperature, the heating air outlet temperature and the engine operation time; when the heating air abundance is greater than the heating air abundance threshold, the hybrid engine is allowed to stop; when the hybrid engine stops, the air conditioner blower and the inside-out circulation air door are regulated and controlled to improve the heating air outlet temperature comfort and the heating air continuous working time. The application analyzes the vehicle cabin heating air comfort under the complex environment change of the vehicle and the air conditioner, thereby controlling the hybrid engine stop and the low-heat operation of the air conditioner, and realizing the oil saving effect to a certain extent.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle control, in particular to a heating control method and device for a hybrid vehicle. BACKGROUND

[0002] In the current vehicle control field, there are two heat source schemes for heating of a hybrid vehicle: PTC heating and engine heat source. Among them, PTC heating requires an additional low or high pressure PTC system to generate heat for heating demand through electric heating, which has the advantages of fast heating, good economic efficiency of the hybrid system, but the cost is high, the system is complex, the heating effect is poor at extremely low temperature, and the engine still needs to be started for heating. Using engine heating can ensure sufficient heat source and simple system, but the engine is always working, which is poor in economy. At present, the engine mechanical water pump is replaced by an electric water pump, so that the engine heat source can still flow to the heating core for heating when the engine is stopped. However, this scheme has a large development workload and high cost for the existing engine.

[0003] Therefore, the technical problem at present is to provide a heating control technology for a hybrid vehicle to meet the current driving demand. SUMMARY

[0004] The present application provides a heating control method and device for a hybrid vehicle, which analyzes the cabin heating comfort in a complex environment of a vehicle and an air conditioner, so as to control the hybrid engine stop and the air conditioner low heat operation, thereby realizing oil saving effect to a certain extent.

[0005] In a first aspect, the present application provides a heating control method for a hybrid vehicle, which comprises the following steps:

[0006] Based on the ambient temperature, the air conditioner target heating temperature, the actual temperature of the cabin, the air conditioner blower air volume gear, the air conditioner blowing mode, the engine water temperature, the heating outlet temperature and the engine running time, the heating comfort of the cabin air conditioner is calculated.

[0007] When the heating comfort is greater than the heating comfort threshold, the hybrid engine is allowed to stop;

[0008] When the hybrid engine is stopped, the air conditioner blower and the inside and outside circulation air door are adjusted to improve the heating outlet temperature comfort and the heating continuous working time.

[0009] It should be noted that in the current hybrid heating hardware scheme, that is, the engine cooperates with the mechanical water pump, the engine is always running to provide sufficient heat source for the air conditioner heating control after the air conditioner heating demand is sent out.

[0010] The technical solution of this application embodiment assesses the air conditioning heating demand and the actual vehicle environment, and separates the heat-rich working condition. Under this working condition, the engine can be stopped, and the air conditioning heating is controlled to operate at a low load to achieve fuel saving and significantly improve the powertrain NVH and cabin air conditioning noise.

[0011] It can achieve low-cost, high-efficiency heating and fuel saving in environments above 0°C, reduce the use of complex external parts, and has a wide range of applications, making it suitable for most HEV models.

[0012] Furthermore, the method also includes the following steps:

[0013] The hybrid engine is not allowed to stop when the heating margin is not greater than the heating margin threshold.

[0014] Based on the technical solution of this application, when a customer requests heating, a preset heat-rich energy-saving module is used to analyze the heating capacity of the cockpit air conditioner based on factors such as ambient temperature, target heating temperature of the air conditioner, actual temperature of the cockpit, air volume setting of the air conditioner blower, air conditioner blowing mode, engine water temperature, temperature of the heating outlet, and engine running time.

[0015] When the heating capacity meets the requirements, the VCU can be allowed to shut down the hybrid engine based on energy management.

[0016] The hybrid engine is not allowed to shut down when the heating capacity is insufficient.

[0017] Accordingly, when the hybrid engine is shut down, the air conditioning low-heat control module is activated, which includes control of the air conditioning blower and control of the internal and external circulation dampers, to improve the comfort and duration of the warm air outlet temperature.

[0018] Furthermore, the method includes a formula for calculating the inlet air temperature of the warm air core:

[0019] T in =K1*T b +(1-K1)*T a ;in,

[0020] T in The inlet air temperature of the warm air core;

[0021] K1 is the mixing ratio of internal and external circulation dampers;

[0022] T a The ambient temperature;

[0023] T b This refers to the temperature inside the driver's cab.

[0024] Furthermore, the method includes a formula for calculating the outlet air temperature of the warm air core:

[0025] T out = f(m w , C pw , C pl , T t , A, h, K2);

[0026]

[0027] m w *C pw *(T t -T t+1 ) = m1*K2*C pl *(T out -T in ); wherein,

[0028] T out is the air temperature at the outlet of the warm air core;

[0029] m w is the mass of the coolant in the warm air core;

[0030] C pw is the specific heat of the coolant;

[0031] m1 is the mass flow rate of the air conditioning warm air flow;

[0032] C pl is the specific heat of the air;

[0033] T t is the coolant temperature at time t after shutdown;

[0034] A is the heat exchange area between the warm air core and the air;

[0035] h is the convective heat transfer coefficient of the warm air core;

[0036] b is a constant heat loss;

[0037] K2 is the warm and cold air door mixing ratio.

[0038] Further, the method includes an air conditioning outlet temperature calculation formula:

[0039] T ac = K2*T out + (1-K2)*T in ; wherein,

[0040] T ac is the air conditioning outlet temperature.

[0041] Specifically, a warm air outlet temperature model is preset, and the warm air temperature can be predicted according to different coolant temperatures, ambient temperatures and air conditioning control parameters. When the warm air outlet temperature T acLow than the customer perception of the allowable temperature T c When, not allow engine stop;

[0042] Customer perception of the allowable temperature T c According to the customer temperature sensitivity of air conditioning outlet, set with the ambient temperature, customer individual difference, car sealing conditions, default for 34 ℃, and can be customized by the customer on the MP5 screen, generally the lower the temperature setting, the longer the warm air stop time, HEV model more fuel-efficient.

[0043] In addition, in specific implementation, a low heat control module of air conditioner can also be designed, which executes the module strategy when the hybrid engine stops, to improve the temperature comfort and duration of the warm air outlet, specifically:

[0044] The air volume of the air blower of the air conditioner is automatically adjusted to a low speed, defaulting to 2 or below, which can be customized by the customer,

[0045] The opening degree of the mixed air door of the internal and external circulation is adjusted to within 50%, which can be 100% in internal circulation in actual operation, which can be customized by the customer.

[0046] It should be noted that the warm air fuel-saving system strategy of the hybrid vehicle includes the rich heat energy-saving module, the hybrid engine stop and the low load operation strategy of the air conditioner;

[0047] The rich heat energy-saving module strategy accurately defines the customer's warm air comfort satisfaction from the scene, forming a fine control;

[0048] The warm air outlet temperature model is widely applicable to the scene and is a key point to achieve warm air fuel saving;

[0049] The customer's self-defined perception of the allowable temperature realizes differentiated and deep self-determined fuel saving.

[0050] In a second aspect, the application provides a warm air fuel-saving control device for a hybrid vehicle, which comprises:

[0051] A warm air richness calculation module is configured to calculate the warm air richness of the cabin air conditioner based on the ambient temperature, the target heating temperature of the air conditioner, the actual temperature of the cockpit, the air volume of the air blower of the air conditioner, the air blowing mode of the air conditioner, the engine water temperature, the warm air outlet temperature, and the engine operation time;

[0052] A warm air richness execution module is configured to allow the hybrid engine to stop when the warm air richness is greater than the warm air richness threshold;

[0053] An oil-saving execution module is configured to, when the hybrid engine stops, control the air blower of the air conditioner and the internal and external circulation air door to improve the temperature comfort and the continuous working time of the warm air outlet.

[0054] It should be noted that under the current hybrid heating hardware solution, i.e. the engine works in conjunction with the mechanical water pump, the engine keeps running after the air conditioning heating demand is issued, providing sufficient heat source for the air conditioning heating control.

[0055] The technical solution of this application embodiment assesses the air conditioning heating demand and the actual vehicle environment, and separates the heat-rich working condition. Under this working condition, the engine can be stopped, and the air conditioning heating is controlled to operate at a low load to achieve fuel saving and significantly improve the powertrain NVH and cabin air conditioning noise.

[0056] It can achieve low-cost, high-efficiency heating and fuel saving in environments above 0°C, reduce the use of complex external parts, and has a wide range of applications, making it suitable for most HEV models.

[0057] Furthermore, the heating air abundance execution module is also used to prevent the hybrid engine from shutting down when the heating air abundance is not greater than the heating air abundance threshold.

[0058] Based on the technical solution of this application, when a customer requests heating, a preset heat-rich energy-saving module is used to analyze the heating capacity of the cockpit air conditioner based on factors such as ambient temperature, target heating temperature of the air conditioner, actual temperature of the cockpit, air volume setting of the air conditioner blower, air conditioner blowing mode, engine water temperature, temperature of the heating outlet, and engine running time.

[0059] When the heating capacity meets the requirements, the VCU can be allowed to shut down the hybrid engine based on energy management.

[0060] The hybrid engine is not allowed to shut down when the heating capacity is insufficient.

[0061] Accordingly, when the hybrid engine is shut down, the air conditioning low-heat control module is activated, which includes control of the air conditioning blower and control of the internal and external circulation dampers, to improve the comfort and duration of the warm air outlet temperature.

[0062] Furthermore, the device includes a formula for calculating the inlet air temperature of the warm air core:

[0063] T in =K1*T b +(1-K1)*T a ;in,

[0064] T in The inlet air temperature of the warm air core;

[0065] K1 is the mixing ratio of internal and external circulation dampers;

[0066] T a The ambient temperature;

[0067] T b This refers to the temperature inside the driver's cab.

[0068] Furthermore, the device includes a formula for calculating the outlet air temperature of the warm air core:

[0069] T out =f(m w C pw C pl T t (A, h, K2);

[0070]

[0071] m w *C pw *(T t -T t+1 )=m1*K2*C pl *(T out -T in );in,

[0072] T out The outlet air temperature of the warm air core;

[0073] m w The mass of coolant in the heater core;

[0074] C pw This refers to the heat capacity ratio of the coolant.

[0075] m1 is the mass flow rate of the air conditioning heating airflow;

[0076] C pl The ratio of air heat capacity;

[0077] T t The coolant temperature at time t after shutdown;

[0078] A represents the heat exchange area between the heater core and the air;

[0079] h is the convective heat transfer coefficient of the heater core;

[0080] b is the heat loss constant;

[0081] K2 represents the mixing ratio of hot and cold air.

[0082] Furthermore, the device includes a formula for calculating the air conditioner outlet temperature:

[0083] T ac =K2*T out +(1-K2)*T in ;in,

[0084] T ac This refers to the temperature at the air conditioner's outlet.

[0085] Specifically, a pre-set model for the temperature of the warm air outlet can predict the warm air temperature based on different coolant temperatures, ambient temperatures, and air conditioning control parameters. When the warm air outlet temperature T... ac Below the customer's perceived allowable temperature T c The engine must not be stopped at this time;

[0086] Customer-perceived allowable temperature T c The temperature setting is based on the customer's sensitivity to the air conditioning vents and is related to the ambient temperature, individual customer differences, and the vehicle's sealing conditions. The default temperature is 34℃, and customers can customize it on the MP5 screen. Generally, the lower the temperature setting, the longer the heating will stop, and the more fuel-efficient the HEV model will be.

[0087] In addition, during implementation, an air conditioning low-heat control module can be designed. This module's strategy is executed when the hybrid engine is off to improve the comfort and duration of the warm air outlet temperature. Specifically:

[0088] The air conditioner blower automatically adjusts to a low fan speed setting, defaulting to level 2 or below, but this can be customized by the customer.

[0089] The opening of the internal and external circulation mixing damper can be adjusted to within 50%. In actual operation, the target internal circulation can be 100%, which can be customized by the customer.

[0090] It should be noted that the heating and fuel-saving system strategy for hybrid vehicles includes a heat-rich energy-saving module, hybrid engine shutdown, and low-load operation strategies such as air conditioning.

[0091] The heat-rich energy-saving module strategy precisely defines the customer's heating comfort satisfaction based on the scenario, forming a refined control.

[0092] The temperature model of the warm air outlet is applicable to a wide range of scenarios and is the key to achieving fuel saving in the warm air system.

[0093] Customers can customize the perceived allowable temperature to achieve differentiation and deep autonomous fuel saving.

[0094] The beneficial effects of the technical solution provided in this application include:

[0095] This application analyzes the cabin heating comfort in response to complex environmental changes in vehicles and air conditioning, thereby controlling the shutdown of the hybrid engine and the low-heat operation of the air conditioning, thus achieving fuel saving to a certain extent. Attached Figure Description

[0096] Terminology Explanation:

[0097] PTC: Positive Temperature Coefficient, a resistance temperature heater;

[0098] NVH: Noise, Vibration, Harshness;

[0099] HEV: Hybrid Electric Vehicle;

[0100] VCU: Vehicle Control Unit;

[0101] EMS: Engine Management System;

[0102] AC: Air Conditioning Controller.

[0103] To more clearly illustrate the technical solutions in the embodiments of this application, the following will briefly introduce the hybrid vehicle heating fuel-saving control method using the accompanying drawings used in the description of the embodiments. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0104] Figure 1 This is a flowchart illustrating the control principle of the hybrid vehicle heating fuel-saving control method provided in this application embodiment. Detailed Implementation

[0105] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0106] The embodiments of this application will be further described in detail below with reference to the accompanying drawings.

[0107] This application provides a method and device for controlling fuel saving in the heating system of a hybrid vehicle. With a mechanical water pump and no PTC thermal management hardware, it achieves a certain degree of fuel saving while meeting heating requirements based on a heating performance model. With a mechanical water pump and PTC thermal management hardware with air heating, it controls the PTC heating power during engine shutdown based on the temperature of the heating outlet, thereby achieving a certain oil reduction effect.

[0108] To achieve the aforementioned technical effects, the overall concept of this application is as follows:

[0109] A method for controlling fuel efficiency in the heating system of a hybrid vehicle, the method comprising the following steps:

[0110] The heating margin of the cockpit air conditioner is calculated based on the ambient temperature, the target heating temperature of the air conditioner, the actual temperature of the cockpit, the air volume setting of the air conditioner blower, the air conditioner blowing mode, the engine water temperature, the temperature of the heating air outlet, and the engine running time.

[0111] When the heating margin is greater than the heating margin threshold, the hybrid engine is allowed to shut down.

[0112] When the hybrid engine is off, the temperature comfort of the warm air outlet and the duration of continuous warm air operation are improved by adjusting the air conditioning blower and the internal and external circulation dampers.

[0113] The embodiments of this application will be further described in detail below with reference to the accompanying drawings.

[0114] Firstly, see [the following] Figure 1 As shown in the embodiment of this application, a method for controlling the fuel economy of a hybrid vehicle's heating system is provided. The method includes the following steps:

[0115] S1. Calculate the heating margin of the cockpit air conditioner based on ambient temperature, target heating temperature of the air conditioner, actual temperature of the cockpit, air volume setting of the air conditioner blower, air conditioning blowing mode, engine water temperature, temperature of the heating air outlet, and engine running time.

[0116] S2. When the heating margin is greater than the heating margin threshold, the hybrid engine is allowed to shut down.

[0117] S3. When the hybrid engine stops, the temperature comfort of the warm air outlet and the duration of continuous warm air operation are improved by adjusting the air conditioning blower and the internal and external circulation dampers.

[0118] It should be noted that under the current hybrid heating hardware solution, i.e. the engine works in conjunction with the mechanical water pump, the engine keeps running after the air conditioning heating demand is issued, providing sufficient heat source for the air conditioning heating control.

[0119] The technical solution of this application embodiment assesses the air conditioning heating demand and the actual vehicle environment, and separates the heat-rich working condition. Under this working condition, the engine can be stopped, and the air conditioning heating is controlled to operate at a low load to achieve fuel saving and significantly improve the powertrain NVH and cabin air conditioning noise.

[0120] It can achieve low-cost, high-efficiency heating and fuel saving in environments above 0°C, reduce the use of complex external parts, and has a wide range of applications, making it suitable for most HEV models.

[0121] The technical solution in this application embodiment analyzes the comfort of the cockpit heating in response to complex environmental changes in the vehicle and air conditioning, thereby controlling the hybrid engine to shut down and the air conditioning to operate at low heat, thus achieving fuel saving to a certain extent.

[0122] Furthermore, the hybrid vehicle's heating fuel-saving control method also includes the following steps:

[0123] The hybrid engine is not allowed to stop when the heating margin is not greater than the heating margin threshold.

[0124] Based on the technical solution of this application embodiment, when a customer requests heating, a preset heat-rich energy-saving module is used to analyze the heating capacity of the cockpit air conditioner based on factors such as ambient temperature, target heating temperature of the air conditioner, actual temperature of the cockpit, air volume setting of the air conditioner blower, air conditioner blowing mode, engine water temperature, temperature of the heating outlet, and engine running time.

[0125] When the heating capacity meets the requirements, the VCU can be allowed to shut down the hybrid engine based on energy management.

[0126] The hybrid engine is not allowed to shut down when the heating capacity is insufficient.

[0127] Correspondingly, when the hybrid engine is shut down, the air conditioning low-heat control module is activated, including air conditioning blower control and internal / external circulation damper control, to improve the comfort and duration of the warm air outlet temperature.

[0128] The specific control principle and process are shown in the attached diagram in the instruction manual. Figure 1 As shown.

[0129] The technical solution based on this application includes at least the following technical advantages:

[0130] By reducing component costs, it can replace low-pressure PTC systems to achieve low-cost heating;

[0131] Reduce fuel consumption of the hybrid system and enable the hybrid engine and air conditioning to operate on demand when the heater is turned on, achieving lean and energy-saving performance;

[0132] User-defined parameter control allows customers to participate in the air conditioning energy management of hybrid vehicles, increasing customer involvement and awareness.

[0133] Furthermore, the hybrid vehicle's heating fuel-saving control method includes a formula for calculating the inlet air temperature of the heating element:

[0134] T in =K1*T b +(1-K1)*T a ;in,

[0135] T inThe inlet air temperature of the warm air core;

[0136] K1 is the mixing ratio of internal and external circulation dampers;

[0137] T a The ambient temperature;

[0138] T b This refers to the temperature inside the driver's cab.

[0139] Furthermore, the hybrid vehicle's heating fuel-saving control method includes a formula for calculating the outlet air temperature of the heating element:

[0140] T out =f(m w C pw C pl T t (A, h, K2);

[0141]

[0142] m w *C pw *(T t -T t+1 )=m1*K2*C pl *(T out -T in );in,

[0143] T out The outlet air temperature of the warm air core;

[0144] m w The mass of coolant in the heater core;

[0145] C pw This refers to the heat capacity ratio of the coolant.

[0146] m1 is the mass flow rate of the air conditioning heating airflow;

[0147] C pl The ratio of air heat capacity;

[0148] T t The coolant temperature at time t after shutdown;

[0149] A represents the heat exchange area between the heater core and the air;

[0150] h is the convective heat transfer coefficient of the heater core;

[0151] b is the heat loss constant;

[0152] K2 represents the mixing ratio of hot and cold air.

[0153] Furthermore, the hybrid vehicle's heating fuel-saving control method includes a formula for calculating the air conditioning vent temperature:

[0154] T ac =K2*T out +(1-K2)*T in ;in,

[0155] T ac This refers to the temperature at the air conditioner's outlet.

[0156] In the technical solution of this application embodiment:

[0157] Based on mechanical water pumps and PTC-free thermal management hardware, fuel savings are achieved to a certain extent while meeting heating requirements, using a heating performance model.

[0158] With a mechanical water pump and PTC thermal management hardware for air heating, the PTC heating power during engine shutdown is controlled based on the temperature of the warm air outlet, thereby achieving a certain oil-cooling effect.

[0159] In specific implementation, based on the technical solution of the embodiments of this application, a heat-rich energy-saving module is designed, and the judgment is made by eight factors that can be perceived by the customer. The judgment factors are defined as shown in Table 1 below.

[0160] Customer perception factor Remark Unit Stop condition Logic 1 Ambient temperature Prohibit stop at extremely low temperature Ta / ℃ ≥0 With 2 Air conditioning heating target temperature Prohibit stop at high demand of warm air Taim / ℃ ≤30 With 3 Actual temperature of cockpit Prohibit stop at low room temperature Tb / ℃ ≥25 With 4 Air conditioning air volume Prohibit stop at high demand of warm air Nc ≤5 With 5 Air conditioning mode Prohibit stop at defrosting and demisting mode / Non-defrosting and demisting mode With 6 Engine water temperature Sufficient heat of warm air core Tcool / ℃ ≥80 With 7 Temperature of warm air outlet Higher than customer perception allowed temperature Tc Tac / ℃ ≥Tc Engine single running time 8 Avoid frequent start-stop of hybrid engine t_runing / min ≥1min ​ ​

[0161] Table 1

[0162] When all the sensing factors are met, it can be determined that the cabin heating is in a state of abundant heat, allowing the hybrid engine to be shut down to achieve energy saving.

[0163] Design a model for the temperature of the warm air outlet. This model calculates the temperature of the warm air outlet, Tac = f(m1,k1,k2,T). a ,T b ,t);

[0164] The model uses the mass and temperature of the coolant in the heater core, heat dissipation area, convective heat transfer coefficient, heat capacity ratio, ambient temperature, cabin temperature, fan flow rate, opening of internal and external circulation dampers, and opening of hot and cold air mixing dampers as control parameters. These parameters are negatively correlated with the heating time t and are specifically defined by the following formula:

[0165] T in =K1*T b +(1-K1)*T a ;

[0166] T out =f(m w C pw C pl T t (A, h, K2);

[0167]

[0168] m w *C pw *(T t -T t+1 )=m1*K2*C pl *(T out -T in );

[0169] T ac =K2*T out +(1-K2)*T in ;in,

[0170] T in The inlet air temperature of the warm air core;

[0171] K1 is the mixing ratio of internal and external circulation dampers, which is related to the opening degree of internal and external circulation dampers;

[0172] T a The ambient temperature;

[0173] T b Temperature inside the driver's cab;

[0174] T out The outlet air temperature of the warm air core;

[0175] m w The mass of coolant in the heater core is related to the volume extracted from the heater core and the density of the coolant.

[0176] C pw The heat capacity ratio of the coolant can be obtained by consulting a material handbook.

[0177] m1 is the mass flow rate of the air conditioning heating airflow, in kg / s, which is related to the air conditioning blower speed and flow rate;

[0178] C pl The air heat capacity ratio can be found in a material handbook.

[0179] T t Let T be the coolant temperature at time t after shutdown. When t = 0, T t =0 represents the engine coolant temperature when the engine is stopped;

[0180] A represents the heat exchange area between the heater core and the air;

[0181] h is the convective heat transfer coefficient of the heating core, which is related to the air volume of the air conditioner blower.

[0182] b is the heat loss constant;

[0183] K2 is the mixing ratio of hot and cold air dampers, which is related to the opening of the internal and external circulation dampers.

[0184] T ac This refers to the temperature at the air conditioner's outlet.

[0185] Among them, h and b need to be calibrated through experiments based on different air conditioning blower air volumes.

[0186] Specifically, the warm air outlet temperature model can predict the warm air temperature based on different coolant temperatures, ambient temperatures, and air conditioning control parameters. When the warm air outlet temperature T... ac Below the customer's perceived allowable temperature T c The engine must not be stopped at this time;

[0187] Customer-perceived allowable temperature T c The temperature setting is based on the customer's sensitivity to the air conditioning vents and is related to the ambient temperature, individual customer differences, and the vehicle's sealing conditions. The default temperature is 34℃, and customers can customize it on the MP5 screen. Generally, the lower the temperature setting, the longer the heating will stop, and the more fuel-efficient the HEV model will be.

[0188] In addition, in specific implementation, based on the technical solution of the embodiments of this application, an air conditioning low-heat control module can be designed. When the hybrid engine stops, the strategy of this module is executed to improve the comfort and duration of the warm air outlet temperature, specifically as follows:

[0189] The air conditioner blower automatically adjusts to a low fan speed setting, defaulting to level 2 or below, but this can be customized by the customer.

[0190] The opening of the internal and external circulation mixing damper can be adjusted to within 50%. In actual operation, the target internal circulation can be 100%, which can be customized by the customer.

[0191] It should be noted that the heating and fuel-saving system strategy for hybrid vehicles includes a heat-rich energy-saving module, hybrid engine shutdown, and low-load operation strategies such as air conditioning.

[0192] The heat-rich energy-saving module strategy precisely defines the customer's heating comfort satisfaction based on the scenario, forming a refined control.

[0193] The temperature model of the warm air outlet is applicable to a wide range of scenarios and is the key to achieving fuel saving in the warm air system.

[0194] Customers can customize the perceived allowable temperature to achieve differentiation and deep autonomous fuel saving.

[0195] Secondly, based on the hybrid vehicle heating fuel-saving control method mentioned in the first aspect, this application provides a hybrid vehicle heating fuel-saving control device, which includes:

[0196] The heating margin calculation module is used to calculate the heating margin of the cockpit air conditioner based on the ambient temperature, the target heating temperature of the air conditioner, the actual temperature of the cockpit, the air volume setting of the air conditioner blower, the air conditioner blowing mode, the engine water temperature, the temperature of the heating air outlet, and the engine running time.

[0197] The heating margin execution module is used to allow the hybrid engine to shut down when the heating margin is greater than the heating margin threshold.

[0198] The fuel-saving module is used to improve the comfort of the air conditioning outlet temperature and the duration of continuous heating by adjusting the air conditioning blower and the internal and external circulation dampers when the hybrid engine is off.

[0199] It should be noted that under the current hybrid heating hardware solution, i.e. the engine works in conjunction with the mechanical water pump, the engine keeps running after the air conditioning heating demand is issued, providing sufficient heat source for the air conditioning heating control.

[0200] The technical solution of this application embodiment assesses the air conditioning heating demand and the actual vehicle environment, and separates the heat-rich working condition. Under this working condition, the engine can be stopped, and the air conditioning heating is controlled to operate at a low load to achieve fuel saving and significantly improve the powertrain NVH and cabin air conditioning noise.

[0201] It can achieve low-cost, high-efficiency heating and fuel saving in environments above 0℃, reduce the use of complex external parts, and has a wide range of applications, applicable to most HEV models;

[0202] The technical solution in this application embodiment analyzes the comfort of the cockpit heating in response to complex environmental changes in the vehicle and air conditioning, thereby controlling the hybrid engine to shut down and the air conditioning to operate at low heat, thus achieving fuel saving to a certain extent.

[0203] Furthermore, the heating air abundance execution module is also used to prevent the hybrid engine from shutting down when the heating air abundance is not greater than the heating air abundance threshold.

[0204] Based on the technical solution of this application embodiment, when a customer requests heating, a preset heat-rich energy-saving module is used to analyze the heating capacity of the cockpit air conditioner based on factors such as ambient temperature, target heating temperature of the air conditioner, actual temperature of the cockpit, air volume setting of the air conditioner blower, air conditioner blowing mode, engine water temperature, temperature of the heating outlet, and engine running time.

[0205] When the heating capacity meets the requirements, the VCU can be allowed to shut down the hybrid engine based on energy management.

[0206] The hybrid engine is not allowed to shut down when the heating capacity is insufficient.

[0207] Accordingly, when the hybrid engine is shut down, the air conditioning low-heat control module is activated, which includes control of the air conditioning blower and control of the internal and external circulation dampers, to improve the comfort and duration of the warm air outlet temperature.

[0208] The technical solution based on this application includes at least the following technical advantages:

[0209] By reducing component costs, it can replace low-pressure PTC systems to achieve low-cost heating;

[0210] Reduce fuel consumption of the hybrid system and enable the hybrid engine and air conditioning to operate on demand when the heater is turned on, achieving lean and energy-saving performance;

[0211] User-defined parameter control allows customers to participate in the air conditioning energy management of hybrid vehicles, increasing customer involvement and awareness.

[0212] Furthermore, the hybrid vehicle's heating fuel-saving control device includes a formula for calculating the inlet air temperature of the heating element:

[0213] T in =K1*T b +(1-K1)*T a ;in,

[0214] T in The inlet air temperature of the warm air core;

[0215] K1 is the mixing ratio of internal and external circulation dampers;

[0216] T a The ambient temperature;

[0217] T b This refers to the temperature inside the driver's cab.

[0218] Furthermore, the hybrid vehicle's heating fuel-saving control device includes a formula for calculating the outlet air temperature of the heating element:

[0219] T out =f(m w C pw C pl T t (A, h, K2);

[0220]

[0221] m w *C pw *(T t -T t+1 )=m1*K2*C pl *(T out -T in );in,

[0222] T out The outlet air temperature of the warm air core;

[0223] m w The mass of coolant in the heater core;

[0224] C pw This refers to the heat capacity ratio of the coolant.

[0225] m1 is the mass flow rate of the air conditioning heating airflow;

[0226] C pl The ratio of air heat capacity;

[0227] T t The coolant temperature at time t after shutdown;

[0228] A represents the heat exchange area between the heater core and the air;

[0229] h is the convective heat transfer coefficient of the heater core;

[0230] b is the heat loss constant;

[0231] K2 represents the mixing ratio of hot and cold air.

[0232] Furthermore, the hybrid vehicle's heating fuel-saving control device includes a formula for calculating the air conditioning vent temperature:

[0233] T ac =K2*T out +(1-K2)*T in ;in,

[0234] T ac This refers to the temperature at the air conditioner's outlet.

[0235] In the technical solution of this application embodiment:

[0236] Based on mechanical water pumps and PTC-free thermal management hardware, fuel savings are achieved to a certain extent while meeting heating requirements, using a heating performance model.

[0237] With a mechanical water pump and PTC thermal management hardware for air heating, the PTC heating power during engine shutdown is controlled based on the temperature of the warm air outlet, thereby achieving a certain oil-cooling effect.

[0238] In specific implementation, based on the technical solution of the embodiments of this application, a heat-rich energy-saving module is designed, and the judgment is made by eight factors that can be perceived by the customer. The judgment factors are defined as shown in Table 1 below.

[0239]

[0240]

[0241] Table 1

[0242] When all the sensing factors are met, it can be determined that the cabin heating is in a state of abundant heat, allowing the hybrid engine to be shut down to achieve energy saving.

[0243] Design a model for the temperature of the warm air outlet. This model calculates the temperature of the warm air outlet, Tac = f(m1, k1, k2, T). a T b ,t);

[0244] The model uses the mass and temperature of the coolant in the heater core, heat dissipation area, convective heat transfer coefficient, heat capacity ratio, ambient temperature, cabin temperature, fan flow rate, opening of internal and external circulation dampers, and opening of hot and cold air mixing dampers as control parameters. These parameters are negatively correlated with the heating time t and are specifically defined by the following formula:

[0245] T in =K1*T b +(1-K1)*T a ;

[0246] T out =f(m w C pw C pl T t (A, h, K2);

[0247]

[0248] m w *C pw *(T t -T t+1 )=m1*K2*C pl *(T out -T in );

[0249] T ac =K2*T out +(1-K2)*T in ;in,

[0250] T in The inlet air temperature of the warm air core;

[0251] K1 is the mixing ratio of internal and external circulation dampers;

[0252] T a The ambient temperature;

[0253] T b Temperature inside the driver's cab;

[0254] T out The outlet air temperature of the warm air core;

[0255] m w The mass of coolant in the heater core;

[0256] C pw This refers to the heat capacity ratio of the coolant.

[0257] m1 is the mass flow rate of the air conditioning heating airflow;

[0258] C pl The ratio of air heat capacity;

[0259] T t The coolant temperature at time t after shutdown;

[0260] A represents the heat exchange area between the heater core and the air;

[0261] h is the convective heat transfer coefficient of the heater core;

[0262] b is the heat loss constant;

[0263] K2 is the mixing ratio of hot and cold air dampers;

[0264] T ac This refers to the temperature at the air conditioner's outlet.

[0265] Specifically, the warm air outlet temperature model can predict the warm air temperature based on different coolant temperatures, ambient temperatures, and air conditioning control parameters. When the warm air outlet temperature T... ac Below the customer's perceived allowable temperature T c The engine must not be stopped at this time;

[0266] Customer-perceived allowable temperature T c The temperature setting is based on the customer's sensitivity to the air conditioning vents and is related to the ambient temperature, individual customer differences, and the vehicle's sealing conditions. The default temperature is 34℃, and customers can customize it on the MP5 screen. Generally, the lower the temperature setting, the longer the heating will stop, and the more fuel-efficient the HEV model will be.

[0267] In addition, in specific implementation, based on the technical solution of the embodiments of this application, an air conditioning low-heat control module can be designed. When the hybrid engine stops, the strategy of this module is executed to improve the comfort and duration of the warm air outlet temperature, specifically as follows:

[0268] The air conditioner blower automatically adjusts to a low fan speed setting, defaulting to level 2 or below, but this can be customized by the customer.

[0269] The opening of the internal and external circulation mixing damper can be adjusted to within 50%. In actual operation, the target internal circulation can be 100%, which can be customized by the customer.

[0270] It should be noted that the heating and fuel-saving system strategy for hybrid vehicles includes a heat-rich energy-saving module, hybrid engine shutdown, and low-load operation strategies such as air conditioning.

[0271] The heat-rich energy-saving module strategy precisely defines the customer's heating comfort satisfaction based on the scenario, forming a refined control.

[0272] The temperature model of the warm air outlet is applicable to a wide range of scenarios and is the key to achieving fuel saving in the warm air system.

[0273] Customers can customize the perceived allowable temperature to achieve differentiation and deep autonomous fuel saving.

[0274] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0275] The above are merely specific embodiments of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for controlling fuel efficiency in the heating system of a hybrid vehicle, characterized in that, The method includes the following steps: The heating margin of the cockpit air conditioner is calculated based on the ambient temperature, the target heating temperature of the air conditioner, the actual temperature of the cockpit, the air volume setting of the air conditioner blower, the air conditioner blowing mode, the engine water temperature, the temperature of the heating air outlet, and the engine running time. When the heating margin is greater than the heating margin threshold, the hybrid engine is allowed to shut down. When the hybrid engine is off, the temperature comfort of the warm air outlet and the duration of continuous warm air operation are improved by adjusting the air conditioning blower and the internal and external circulation dampers. The method includes a formula for calculating the temperature of the warm air outlet: ;in, This refers to the temperature of the warm air outlet. The inlet air temperature of the warm air core; The outlet air temperature of the warm air core; The formula for calculating the inlet air temperature of the warm air core is as follows: ;in, K1 is the mixing ratio of internal and external circulation dampers; T a Ambient temperature; T b Temperature inside the driver's cab; The formula for calculating the outlet air temperature of the warm air core is as follows: ； ； ;in, The mass of coolant in the heater core; This refers to the heat capacity ratio of the coolant. Mass flow rate of the air conditioning heating airflow; The ratio of air heat capacity; T t The coolant temperature at time t after shutdown; A represents the heat exchange area between the heater core and the air; h is the convective heat transfer coefficient of the heater core; b is the heat loss constant; K2 is the mixing ratio of hot and cold air dampers; The hybrid engine is not allowed to stop when the heating margin is not greater than the heating margin threshold.

2. A hybrid vehicle heating fuel-saving control device, which operates according to the method described in claim 1, characterized in that, The device includes: The heating margin calculation module is used to calculate the heating margin of the cockpit air conditioner based on the ambient temperature, the target heating temperature of the air conditioner, the actual temperature of the cockpit, the air volume setting of the air conditioner blower, the air conditioner blowing mode, the engine water temperature, the temperature of the heating air outlet, and the engine running time. The heating margin execution module is used to allow the hybrid engine to shut down when the heating margin is greater than the heating margin threshold. The fuel-saving module is used to improve the comfort of the air conditioning outlet temperature and the duration of continuous heating by adjusting the air conditioning blower and the internal and external circulation dampers when the hybrid engine is off.

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