A heating control method based on a vehicle heat pump system and a vehicle

Abstract

The application provides a heating control method based on a vehicle heat pump system and an automobile. The method comprises the following steps: when a heating request of the vehicle heat pump system is obtained, an ambient temperature is obtained, and a matched heating mode is determined according to the ambient temperature; according to a valve control strategy corresponding to the matched heating mode, the internal air cooler is controlled to perform a heating treatment in the automobile, or the internal air cooler and the evaporator are controlled to perform a heating treatment in the automobile; according to a set temperature, an indoor temperature, an actual air outlet temperature and a pipeline loss corresponding to the matched heating mode, a compressor target rotating speed in the matched heating mode is obtained; and the compressor is controlled to operate according to the compressor target rotating speed; according to an actual pressure of the vehicle heat pump system and a target pressure corresponding to the matched heating mode, an electronic expansion valve target opening degree in the matched heating mode is obtained; and the electronic expansion valve is adjusted according to the electronic expansion valve target opening degree.

Description

Technical Field

[0001] This application relates to the field of new energy vehicle technology, and in particular to a heating control method based on a vehicle heat pump system and a vehicle. Background Technology

[0002] Existing new energy vehicles equipped with heat pump systems generally use a simple series connection between the internal air cooler and evaporator in the heat pump system to provide heat to the vehicle interior.

[0003] However, when the ambient temperature is high, the internal air cooler and evaporator contain high-temperature and high-pressure gaseous refrigerant, which often cannot fully exchange heat with the cold air inside the car, thus affecting the heating effect and resulting in relatively low heating efficiency of this type of heat pump system. Summary of the Invention

[0004] This application provides a heating control method and a vehicle based on a vehicle heat pump system, which is used to solve the problems of poor heating effect and low heating efficiency ratio of existing new energy vehicle heat pump systems.

[0005] In a first aspect, this application provides a heating control method based on an automotive heat pump system, comprising: upon receiving a heating request from the automotive heat pump system, acquiring an ambient temperature and determining a matching heating mode based on the ambient temperature; controlling the internal air cooler of the automotive heat pump system to provide heating for the vehicle interior, or controlling the internal air cooler and evaporator to provide heating for the vehicle interior, according to a valve control strategy corresponding to the matching heating mode; acquiring a target compressor speed under the matching heating mode based on the acquired set temperature, interior temperature, actual air outlet temperature, and pipe loss corresponding to the matching heating mode; and controlling the compressor in the automotive heat pump system to operate according to the target compressor speed; acquiring a target opening degree of the electronic expansion valve under the matching heating mode based on the actual pressure of the automotive heat pump system and the target pressure corresponding to the matching heating mode; and adjusting the electronic expansion valve in the automotive heat pump system according to the target opening degree of the electronic expansion valve.

[0006] In one specific implementation, determining the matching heating mode based on the ambient temperature includes: when the ambient temperature is greater than or equal to a first ambient threshold, determining the matching heating mode as a first heating mode or a second heating mode; then, controlling the internal air cooler of the vehicle heat pump system to provide heating for the vehicle interior, or controlling the internal air cooler and evaporator to provide heating for the vehicle interior, according to the valve control strategy corresponding to the matching heating mode, includes: according to the first valve control strategy matched to the first heating mode or the second heating mode, respectively triggering the second, third, and sixth shut-off valves of the vehicle heat pump system to open, the first, fourth, and fifth shut-off valves to close, the external air cooler outlet electronic expansion valve to open, and the evaporator inlet electronic expansion valve to close, so as to control the internal air cooler of the vehicle heat pump system to provide heating for the vehicle interior.

[0007] In one specific implementation, determining the matching heating mode based on the ambient temperature includes: when the ambient temperature is less than a first ambient threshold, determining the matching heating mode as a third heating mode; then, controlling the internal air cooler of the vehicle heat pump system to provide heating for the vehicle interior, or controlling the internal air cooler and evaporator to provide heating for the vehicle interior, according to the valve control strategy corresponding to the matching heating mode, includes: according to the second valve control strategy matched to the third heating mode, triggering the second, third, and fifth shut-off valves of the vehicle heat pump system to open, the first, fourth, and sixth shut-off valves to close, and the evaporator inlet electronic expansion valve and the external air cooler outlet electronic expansion valve to open, so as to control the internal air cooler and evaporator of the vehicle heat pump system to provide heating for the vehicle interior.

[0008] In one specific embodiment, the step of obtaining the target compressor speed under the matched heating mode based on the acquired set temperature, in-vehicle temperature, actual air outlet temperature, and pipe loss corresponding to the matched heating mode; and controlling the compressor operation in the vehicle heat pump system according to the target compressor speed, includes: obtaining the in-vehicle temperature and the input set temperature, and obtaining the target air outlet temperature of the internal air cooler in the vehicle heat pump system based on the set temperature, the in-vehicle temperature, and pipe loss corresponding to the heating mode; obtaining the actual air outlet temperature of the internal air cooler, and determining the target compressor speed under the matched heating mode based on the actual air outlet temperature and the target air outlet temperature; and controlling the compressor in the vehicle heat pump system to operate at the target compressor speed.

[0009] In one specific embodiment, obtaining the target outlet air temperature of the internal air cooler in the vehicle heat pump system based on the set temperature, the vehicle interior temperature, and the pipe loss corresponding to the heating mode includes: based on the set temperature T... S and the vehicle interior temperature T I The formula used is: T B =(T S -22)+K1(T S -T I The target outlet air temperature T of the blower in the automotive heat pump system is obtained by adding K2 to K3 and then adding T0. B Where K1 is the temperature difference coefficient, K2 is the ambient temperature coefficient, K3 is the sunlight influence coefficient, and T0 is the temperature compensation value; based on the target outlet air temperature T of the blower. B And the pipeline loss T corresponding to the heating mode L The formula used is: T C =T B +T L Obtain the target outlet air temperature T of the internal air cooler in the automotive heat pump system. C .

[0010] In one specific implementation, determining the compressor target speed under the matched heating mode based on the actual outlet air temperature and the target outlet air temperature includes: obtaining the difference e(t) between the actual outlet air temperature and the target outlet air temperature at the current time t every preset time T, using the formula:

[0011]

[0012] Obtain the compressor target speed U(t) at the current time t; where K p U0 is the proportional coefficient, and U0 is the compressor speed constant.

[0013] In one specific embodiment, the step of obtaining the target opening degree of the electronic expansion valve under the matched heating mode based on the actual pressure of the vehicle heat pump system and the target pressure corresponding to the matched heating mode, and adjusting the electronic expansion valve in the vehicle heat pump system according to the target opening degree of the electronic expansion valve, includes: obtaining the actual discharge pressure of the compressor and the target discharge pressure of the compressor corresponding to the heating mode, and determining the target opening degree of the electronic expansion valve based on the actual discharge pressure and the target discharge pressure of the compressor; and controlling the electronic expansion valve in the vehicle heat pump system to adjust according to the target opening degree of the electronic expansion valve.

[0014] In one specific embodiment, determining the target opening degree of the electronic expansion valve based on the actual discharge pressure and the target discharge pressure of the compressor includes: obtaining the difference f(t) between the actual discharge pressure and the target discharge pressure at the current time t every preset time T, using the formula:

[0015]

[0016] Obtain the target opening V(t) of the electronic expansion valve at the current time t; where K p V0 is the proportional coefficient, and V0 is the opening constant of the electronic expansion valve.

[0017] In a second aspect, this application provides an electronic control unit, including: a processor, a memory, and a communication interface; the memory is used to store executable instructions of the processor; wherein the processor is configured to execute the heating control method based on an automotive heat pump system described in the first aspect by executing the executable instructions.

[0018] Thirdly, this application provides a new energy vehicle, including: an electronic control unit as described in the second aspect and a vehicle heat pump system.

[0019] This application provides a heating control method and a vehicle based on a vehicle heat pump system. The method includes: acquiring the ambient temperature when a heating request is received from the vehicle heat pump system, and determining a matching heating mode based on the ambient temperature; controlling the internal air cooler of the vehicle heat pump system to provide heating for the vehicle interior, or controlling the internal air cooler and evaporator to provide heating for the vehicle interior, according to the valve control strategy corresponding to the matching heating mode; acquiring the compressor target speed in the matching heating mode based on the acquired set temperature, interior temperature, actual air outlet temperature, and pipe loss corresponding to the matching heating mode; and controlling the compressor in the vehicle heat pump system to operate according to the compressor target speed; acquiring the electronic expansion valve target opening degree in the matching heating mode based on the actual pressure of the vehicle heat pump system and the target pressure corresponding to the matching heating mode; and adjusting the electronic expansion valve in the vehicle heat pump system according to the electronic expansion valve target opening degree. Compared to existing heat pump systems in new energy vehicles that simply connect an internal air cooler and evaporator in series for vehicle heating, this application determines a matching heating mode based on the ambient temperature upon receiving a heating request. In this matching mode, it controls the internal air cooler to provide heating either independently or in series with the evaporator. Simultaneously, based on the set temperature, vehicle interior temperature, actual air outlet temperature, actual pressure of the vehicle heat pump system, target pressure, and the corresponding pipe losses for the matching heating mode, it obtains the target compressor speed and target electronic expansion valve opening for that mode. Controlling the compressor's operation based on the target speed ensures that the compressor's exhaust temperature is at a heat exchange temperature suitable for the current ambient temperature. Adjusting the electronic expansion valve based on its target opening ensures that the compressor's exhaust pressure is at a heat exchange pressure suitable for the current ambient temperature. This allows the vehicle heat pump system to operate in a mode appropriate for the current ambient temperature, effectively improving the heating effect inside the vehicle and increasing the heating efficiency ratio. This solves the problems of poor heating effect and low heating efficiency ratio in existing heat pump systems for new energy vehicles. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This application provides a structural schematic diagram of an automotive heat pump system;

[0022] Figure 2 A flowchart illustrating an embodiment of a heating control method based on an automotive heat pump system provided in this application;

[0023] Figure 3a A schematic diagram of the structure of an embodiment of the vehicle heat pump system in the first heating mode or the second heating mode provided in this application;

[0024] Figure 3b A schematic diagram of the structure of an embodiment of an automotive heat pump system in the third heating mode provided in this application;

[0025] Figure 4 A schematic flowchart of a second embodiment of a heating control method based on an automotive heat pump system provided in this application;

[0026] Figure 5 A schematic flowchart of Embodiment 3 of a heating control method based on an automotive heat pump system provided in this application;

[0027] Figure 6 This is a schematic diagram of the structure of an electronic control unit provided in this application.

[0028] Explanation of reference numerals in the attached figures:

[0029] 101: Compressor; 102: Internal air cooler; 103: Evaporator; 104: External air cooler; 105: Regenerator; 106: Gas-liquid separator; 107: First shut-off valve; 108: Second shut-off valve; 109: Third shut-off valve; 110: Fourth shut-off valve; 111: Fifth shut-off valve; 112: Sixth shut-off valve; 113: Water-cooled air cooler; 114: Battery cooler; 115: Evaporator inlet electronic expansion valve; 116: External air cooler outlet electronic expansion valve; 117: Battery cooler inlet electronic expansion valve; 118: Blower. Detailed Implementation

[0030] 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 made by those skilled in the art under the guidance of these embodiments are within the scope of protection of this application.

[0031] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a particular order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0032] First, let me explain the terms used in this application:

[0033] Energy efficiency ratio (EER): This refers to the ratio of energy conversion efficiency. The higher the EER, the more electricity is saved. In the context of heat pump systems, it refers to the ratio of rated heating capacity to rated power (electricity consumption).

[0034] PI control: Based on the control deviation between the given value and the actual output value, the proportional and integral of the deviation are linearly combined to form the control quantity, which controls the controlled object.

[0035] Existing new energy vehicles equipped with heat pump systems generally use a simple series connection between the internal air cooler and evaporator in the heat pump system to provide heat to the vehicle interior.

[0036] However, when the ambient temperature is high, the internal air cooler and evaporator contain high-temperature and high-pressure gaseous refrigerant, which often cannot fully exchange heat with the cold air inside the car, thus affecting the heating effect and resulting in relatively low heating efficiency of this type of heat pump system.

[0037] Based on the above-mentioned technical problems, the technical concept of this application is as follows: How to provide a heating control method that can be applied to the current ambient temperature to improve the heating effect of the vehicle heat pump system and increase the heating energy efficiency ratio.

[0038] The technical solution of this application will now be described in detail through specific embodiments. It should be noted that the following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0039] Figure 1 This is a structural schematic diagram of a vehicle heat pump system provided in this application. Figure 1As shown, the vehicle heat pump system includes: a compressor 101, an internal air cooler 102, an evaporator 103, an external air cooler 104, a regenerator 105, a gas-liquid separator 106, a first shut-off valve 107, a second shut-off valve 108, a third shut-off valve 109, a fourth shut-off valve 110, a fifth shut-off valve 111, a sixth shut-off valve 112, a water-cooled air cooler 113, a battery cooler 114, an evaporator inlet electronic expansion valve 115, an external air cooler outlet electronic expansion valve 116, a battery cooler inlet electronic expansion valve 117, and a blower 118. A refrigerant flows through the heat pump system for cooling or heating the vehicle interior. For example, the refrigerant is CO2.

[0040] In heating mode, compressor 101 generates high-temperature and high-pressure CO2 gas, which is dissipated through internal air cooler 102 or in series with evaporator 103 to exchange heat with the air inside the car, thereby providing heat to the car interior.

[0041] Figure 2 This is a schematic flowchart illustrating an embodiment of a heating control method based on an automotive heat pump system provided in this application. See also... Figure 2 The heating control method based on the vehicle heat pump system specifically includes the following steps:

[0042] Step S201: When obtaining a heating request from the vehicle heat pump system, obtain the ambient temperature and determine the matching heating mode based on the ambient temperature.

[0043] Step S202: According to the valve control strategy corresponding to the matched heating mode, control the internal air cooler of the vehicle heat pump system to provide heating for the vehicle interior, or control the internal air cooler and evaporator to provide heating for the vehicle interior.

[0044] In this embodiment, when a heating request is received from the vehicle heat pump system, the ambient temperature is obtained. Different ambient temperatures are matched with different heating modes. For example, when the ambient temperature is greater than or equal to 10°C and less than 20°C, a first heating mode is matched; when the ambient temperature is greater than or equal to 0°C and less than 10°C, a second heating mode is matched; and when the ambient temperature is less than 0°C, a third heating mode is matched. The matching heating mode is determined based on the ambient temperature.

[0045] Step S203: Based on the obtained set temperature, in-vehicle temperature, actual air outlet temperature, and pipe loss corresponding to the matched heating mode, obtain the compressor target speed under the matched heating mode; and control the compressor operation in the vehicle heat pump system according to the compressor target speed.

[0046] In this embodiment, the set temperature is the user-defined desired temperature inside the vehicle; for example, the set temperature is 26°C. The vehicle interior temperature is the current actual temperature inside the vehicle; for example, the vehicle interior temperature can be 15°C. The actual air outlet temperature is the actual air outlet temperature of the internal air cooler in the automotive heat pump system. The pipe loss is the temperature loss of the refrigerant in the pipes under different heating modes; for example, the pipe loss corresponding to the first heating mode is 1°C; the pipe loss corresponding to the second heating mode is 2°C; and the pipe loss corresponding to the third heating mode is 3°C.

[0047] Based on the set temperature, the interior temperature, the actual air outlet temperature, and the pipe loss corresponding to the matching heating mode, the target compressor speed under the matching heating mode can be obtained, and then the operation of the compressor in the vehicle heat pump system can be controlled according to the target compressor speed.

[0048] Step S204: Based on the actual pressure of the vehicle heat pump system and the target pressure corresponding to the matching heating mode, obtain the target opening degree of the electronic expansion valve under the matching heating mode; and adjust the electronic expansion valve in the vehicle heat pump system according to the target opening degree of the electronic expansion valve.

[0049] In this embodiment, the actual pressure of the automotive heat pump system is the actual discharge pressure of the compressor. For example, the actual pressure can be 100 bar. The target pressure is the target discharge pressure of the compressor. Different heating modes correspond to different target pressures. For example, the target pressure corresponding to the first heating mode is 70 bar; the target pressure corresponding to the second heating mode is 95 bar; and the target pressure corresponding to the third heating mode is 105 bar.

[0050] Based on the actual pressure of the vehicle heat pump system and the target pressure corresponding to the matching heating mode, the target opening degree of the electronic expansion valve under the matching heating mode can be obtained. Then, the electronic expansion valve in the vehicle heat pump system is adjusted according to this target opening degree. Specifically, the electronic expansion valve at the outlet of the external air cooler is adjusted according to the target opening degree.

[0051] In this embodiment, when a heating request is received from the vehicle heat pump system, the ambient temperature is acquired, and a matching heating mode is determined based on the ambient temperature. According to the valve control strategy corresponding to the matching heating mode, the internal air cooler in the vehicle heat pump system is controlled to heat the vehicle interior, or the internal air cooler and evaporator are controlled to heat the vehicle interior. Based on the acquired set temperature, interior temperature, actual air outlet temperature, and pipe losses corresponding to the matching heating mode, the target compressor speed in the matching heating mode is acquired. The compressor in the vehicle heat pump system is controlled to operate according to the target compressor speed. The target opening degree of the electronic expansion valve in the matching heating mode is acquired based on the actual pressure of the vehicle heat pump system and the target pressure corresponding to the matching heating mode. The electronic expansion valve in the vehicle heat pump system is adjusted according to the target opening degree. Compared to existing heat pump systems in new energy vehicles that simply connect an internal air cooler and evaporator in series for vehicle heating, this application determines a matching heating mode based on the ambient temperature upon receiving a heating request. In this matching mode, it controls the internal air cooler to provide heating either independently or in series with the evaporator. Simultaneously, based on the set temperature, vehicle interior temperature, actual air outlet temperature, actual pressure of the vehicle heat pump system, target pressure, and the corresponding pipe losses for the matching heating mode, it obtains the target compressor speed and target electronic expansion valve opening for that mode. Controlling the compressor's operation based on the target speed ensures that the compressor's exhaust temperature is at a heat exchange temperature suitable for the current ambient temperature. Adjusting the electronic expansion valve based on its target opening ensures that the compressor's exhaust pressure is at a heat exchange pressure suitable for the current ambient temperature. This allows the vehicle heat pump system to operate in a mode appropriate for the current ambient temperature, effectively improving the heating effect inside the vehicle and increasing the heating efficiency ratio. This solves the problems of poor heating effect and low heating efficiency ratio in existing heat pump systems for new energy vehicles.

[0052] In the above Figure 2 Based on the illustrated embodiment, when the ambient temperature is greater than or equal to a first ambient threshold, the matching heating mode is determined to be either the first heating mode or the second heating mode. For example, the first ambient threshold is 0°C. Therefore, a specific implementation of step S202 above is as follows:

[0053] Step S2021: According to the first valve control strategy matched by the first heating mode or the second heating mode, the second shut-off valve, the third shut-off valve, and the sixth shut-off valve in the vehicle heat pump system are respectively triggered to open, the first shut-off valve, the fourth shut-off valve, and the fifth shut-off valve are closed, the external air cooler outlet electronic expansion valve is opened, and the evaporator inlet electronic expansion valve is closed, so as to control the internal air cooler in the vehicle heat pump system to provide heating for the vehicle interior.

[0054] In this embodiment, with Figure 3a For example, Figure 3a This is a structural diagram of an embodiment of the vehicle heat pump system provided in this application under the first or second heating mode. Referring to this structural diagram, step S2021 is specifically implemented as follows: the second shut-off valve 108, the third shut-off valve 109, and the sixth shut-off valve 112 in the vehicle heat pump system are open, while the first shut-off valve 107, the fourth shut-off valve 110, and the fifth shut-off valve 111 are closed. At this time, the vehicle heat pump system is in heating mode. The external air cooler outlet electronic expansion valve 116 is open, and the evaporator inlet electronic expansion valve 115 is closed. At this time, the internal air cooler in the vehicle heat pump system exchanges heat with the air inside the vehicle, providing heating for the vehicle interior.

[0055] In the above Figure 2 Based on the illustrated embodiment, when the ambient temperature is lower than a first ambient threshold, the matching heating mode is determined to be the third heating mode. For example, the first ambient threshold is 0°C. Therefore, a specific implementation of step S202 above is as follows:

[0056] Step S2022: According to the second valve control strategy matched by the third heating mode, the second, third, and fifth shut-off valves in the vehicle heat pump system are triggered to open, the first, fourth, and sixth shut-off valves are closed, and the evaporator inlet electronic expansion valve and the external air cooler outlet electronic expansion valve are opened, so as to control the internal air cooler and evaporator in the vehicle heat pump system to provide heating for the vehicle interior.

[0057] In this embodiment, with Figure 3b For example, Figure 3b This is a structural diagram of an embodiment of the vehicle heat pump system in the third heating mode provided in this application. Referring to this structural diagram, step S2022 is specifically implemented as follows: the second shut-off valve 108, the third shut-off valve 109, and the fifth shut-off valve 111 in the vehicle heat pump system are open, while the first shut-off valve 107, the fourth shut-off valve 110, and the sixth shut-off valve 112 are closed. The vehicle heat pump system is in heating mode at this time. The evaporator inlet electronic expansion valve 115 and the external air cooler outlet electronic expansion valve 116 are open. At this time, both the internal air cooler and the evaporator in the vehicle heat pump system exchange heat with the air inside the vehicle, jointly heating the vehicle interior.

[0058] In this embodiment, a matching heating mode is determined based on the ambient temperature. When the ambient temperature is high, the internal air cooler is used to provide heating for the vehicle interior. When the ambient temperature is low, the internal air cooler and evaporator are connected in series to provide heating for the vehicle interior. This allows the vehicle heat pump system to operate in a mode suitable for the current ambient temperature, providing a prerequisite for further combining the control of compressor speed and electronic expansion valve opening to improve the heating effect and increase the heating energy efficiency ratio in the vehicle interior.

[0059] Figure 4 This is a flowchart illustrating a second embodiment of a heating control method based on an automotive heat pump system provided in this application. Figure 2 as well as Figure 3a , Figure 3b Based on the illustrated embodiment, see also Figure 4 The above step S203 specifically includes the following steps:

[0060] Step S401: Obtain the vehicle interior temperature and the input set temperature, and based on the set temperature, the vehicle interior temperature, and the pipe loss corresponding to the heating mode, obtain the target air outlet temperature of the internal air cooler in the vehicle heat pump system.

[0061] In this embodiment, the user-inputted set temperature and the vehicle interior temperature are obtained. For example, the set temperature is 26°C, while the current vehicle interior temperature is 15°C. In this case, the target air outlet temperature of the internal air cooler in the vehicle heat pump system needs to be obtained, taking into account the pipe losses corresponding to the heating mode.

[0062] Specifically, first, based on the set temperature T S and the temperature inside the car (T) I The formula used is: T B =(T S -22)+K1(T S -T I )+K2-K3+T0, obtain the target outlet air temperature T of the blower in the automotive heat pump system. B Where K1 is the temperature difference coefficient, K2 is the ambient temperature coefficient, K3 is the sunlight influence coefficient, and T0 is the temperature compensation value. For example, K1 can be 8, K2 can be 50, K3 can be 50, and T0 can be 120.

[0063] In obtaining the target outlet air temperature T of the blower B Then, based on the target outlet air temperature T of the blower B And the pipeline loss T corresponding to the heating mode L The formula used is: T C =T B +T L Obtain the target outlet air temperature T of the internal air cooler in the vehicle heat pump system. C For example, the pipe loss T corresponding to the first heating mode. L The temperature is 1℃; the pipe loss T corresponding to the second heating mode is... L The temperature is 2℃; the pipe loss T corresponding to the third heating mode is... L The temperature is 3℃.

[0064] Step S402: Obtain the actual air outlet temperature of the internal air cooler, and determine the target compressor speed in the matching heating mode based on the actual air outlet temperature and the target air outlet temperature.

[0065] Step S403: Control the compressor in the vehicle heat pump system to operate at the target compressor speed.

[0066] In this embodiment, the compressor speed is controlled by PI control based on the difference between the actual outlet air temperature of the internal air cooler and the target outlet air temperature.

[0067] Specifically, after obtaining the target air outlet temperature of the internal air cooler, the actual air outlet temperature of the internal air cooler must be combined to determine the target compressor speed for the matching heating mode.

[0068] Every preset time interval T, the difference e(t) between the actual outlet air temperature and the target outlet air temperature at the current time t is obtained, using the formula:

[0069]

[0070] Obtain the compressor target speed U(t) at the current time t; where K p Where K is the proportionality constant, and U0 is the compressor speed constant. For example, K... p It can be 100, and U0 can be 1200.

[0071] For example, the preset time T can be 100ms. Every 100ms, the difference between the actual outlet air temperature and the target outlet air temperature of the internal air cooler at the current time t is obtained, and the target compressor speed at the current time t is obtained using the above formula, and the compressor is controlled to operate at the target compressor speed.

[0072] In this embodiment, the target air outlet temperature of the internal air cooler is obtained based on the set temperature, the in-vehicle temperature, and the pipe loss corresponding to the heating mode. Based on the actual air outlet temperature and the target air outlet temperature, the target compressor speed in the matching heating mode is determined. By controlling the compressor in the vehicle heat pump system to operate at the target compressor speed, the temperature of the high-temperature and high-pressure refrigerant gas generated by the compressor can be kept at a heat exchange temperature suitable for the current ambient temperature, effectively improving the heating effect inside the car and increasing the heating energy efficiency ratio.

[0073] Figure 5 This is a flowchart illustrating a third embodiment of a heating control method based on a vehicle heat pump system provided in this application. Figures 2 to 4 Based on the illustrated embodiment, see also Figure 5 The above step S204 specifically includes the following steps:

[0074] Step S501: Obtain the actual discharge pressure of the compressor and the target discharge pressure of the compressor corresponding to the heating mode, and determine the target opening degree of the electronic expansion valve based on the actual discharge pressure and the target discharge pressure of the compressor.

[0075] Step S502: Control the electronic expansion valve in the vehicle heat pump system to adjust according to the target opening degree of the electronic expansion valve.

[0076] In this embodiment, different heating modes correspond to different target exhaust pressures. For example, the target exhaust pressure for the first heating mode is 70 bar, the target exhaust pressure for the second heating mode is 95 bar, and the target exhaust pressure for the third heating mode is 105 bar.

[0077] The actual discharge pressure of the compressor can be obtained through a pressure sensor. Based on the actual discharge pressure and the target discharge pressure, the target opening degree of the electronic expansion valve is determined. Specifically, the target opening degree of the electronic expansion valve at the outlet of the external air cooler is determined.

[0078] Specifically, at preset time intervals T, the difference f(t) between the actual exhaust pressure and the target exhaust pressure at the current time t is obtained, using the formula:

[0079]

[0080] Obtain the target opening V(t) of the electronic expansion valve at the current time t; where K p Where K is the proportional coefficient, and V0 is the opening constant of the electronic expansion valve. For example, K... p It can be 10, and V0 can be 60.

[0081] For example, the preset time T can be 100ms. Every 100ms, the difference between the actual discharge pressure and the target discharge pressure of the compressor at the current time t is obtained, and the target opening degree of the electronic expansion valve at the current time t is obtained using the above formula. The electronic expansion valve is then controlled to adjust according to the target opening degree.

[0082] In this embodiment, the target opening degree of the electronic expansion valve is determined based on the actual discharge pressure and the target discharge pressure of the compressor, and the electronic expansion valve in the vehicle heat pump system is controlled to adjust according to the target opening degree of the electronic expansion valve. This allows the discharge pressure of the compressor to be at a heat exchange pressure suitable for the current ambient temperature, effectively improving the heating effect in the car and increasing the heating energy efficiency ratio.

[0083] Figure 6 This is a schematic diagram of an electronic control unit provided in this application. Figure 6As shown, the electronic control unit 60 includes: a processor 61, a memory 62, and a communication interface 63; wherein, the memory 62 is used to store executable instructions of the processor 61; the processor 61 is configured to execute the technical solutions in any of the foregoing method embodiments by executing the executable instructions.

[0084] Optionally, the memory 62 can be either standalone or integrated with the processor 61.

[0085] Optionally, when the memory 62 is a device independent of the processor 61, the electronic device 60 may further include a bus 64 for connecting the aforementioned devices.

[0086] The electronic device is used to execute the technical solutions in any of the foregoing method embodiments. Its implementation principle and technical effect are similar, and will not be described again here.

[0087] This embodiment also provides a new energy vehicle, which includes, as shown in the example below. Figure 6 The electronic control unit and automotive heat pump system shown will not be described in detail here.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A heating control method based on a vehicular heat pump system, characterized by, include: When a heating request is received from a vehicle heat pump system, the ambient temperature is obtained, and a matching heating mode is determined based on the ambient temperature. According to the valve control strategy corresponding to the matching heating mode, the internal air cooler in the vehicle heat pump system is controlled to provide heating for the vehicle interior, or the internal air cooler and evaporator are controlled to provide heating for the vehicle interior. Based on the obtained set temperature, in-vehicle temperature, actual air outlet temperature, and pipe loss corresponding to the matched heating mode, the compressor target speed under the matched heating mode is obtained. And control the operation of the compressor in the vehicle heat pump system according to the target speed of the compressor; Based on the actual pressure of the vehicle heat pump system and the target pressure corresponding to the matched heating mode, the target opening degree of the electronic expansion valve under the matched heating mode is obtained. The electronic expansion valve in the vehicle heat pump system is adjusted according to the target opening degree of the electronic expansion valve. The step of determining the matching heating mode based on the ambient temperature includes: When the ambient temperature is greater than or equal to the first ambient threshold, the matching heating mode is determined to be either the first heating mode or the second heating mode. The method of controlling the internal air cooler of the vehicle heat pump system to provide heating for the vehicle interior according to the valve control strategy corresponding to the matched heating mode, or controlling the internal air cooler and evaporator to provide heating for the vehicle interior, includes: According to the first valve control strategy matched by the first heating mode or the second heating mode, the second, third, and sixth shut-off valves in the vehicle heat pump system are triggered to open, while the first, fourth, and fifth shut-off valves are closed. The external air cooler outlet electronic expansion valve is opened, and the evaporator inlet electronic expansion valve is closed, so as to control the internal air cooler in the vehicle heat pump system to provide heating for the vehicle interior.

2. The heating control method based on the vehicular heat pump system according to claim 1, characterized by, The step of determining the matching heating mode based on the ambient temperature further includes: When the ambient temperature is less than the first ambient threshold, the matching heating mode is determined to be the third heating mode; The method of controlling the internal air cooler of the vehicle heat pump system to provide heating for the vehicle interior according to the valve control strategy corresponding to the matched heating mode, or controlling the internal air cooler and evaporator to provide heating for the vehicle interior, includes: According to the second valve control strategy matched by the third heating mode, the second, third, and fifth shut-off valves in the vehicle heat pump system are triggered to open, while the first, fourth, and sixth shut-off valves are closed. The evaporator inlet electronic expansion valve and the external air cooler outlet electronic expansion valve are opened to control the internal air cooler and evaporator in the vehicle heat pump system to provide heating for the vehicle interior.

3. The heating control method based on a vehicular heat pump system according to claim 1 or 2, characterized by, The compressor target speed under the matched heating mode is obtained based on the set temperature, the in-vehicle temperature, the actual air outlet temperature, and the pipe loss corresponding to the matched heating mode. And based on the target compressor speed, control the operation of the compressor in the automotive heat pump system, including: acquire a target air outlet temperature of an internal air cooler in the vehicle heat pump system according to the set temperature, the indoor temperature and a pipeline loss corresponding to the heating mode; acquire an actual air outlet temperature of the internal air cooler, and determine the compressor target rotating speed in the matched heating mode according to the actual air outlet temperature and the target air outlet temperature; control the compressor in the vehicle heat pump system to operate at the compressor target rotating speed.

4. The heating control method based on the vehicular heat pump system according to claim 3, characterized by, The acquiring of the target air outlet temperature of the internal air cooler in the vehicle heat pump system according to the set temperature, the indoor temperature and the pipeline loss corresponding to the heating mode comprises: According to the set temperature T S and the temperature T I inside the vehicle, the formula is adopted: T B = (T S - 22) + K1(T S - T I ) + K2 - K3 + T0 Acquiring a target air outlet temperature T of a blower in the vehicle heat pump system B ; wherein K1 is a temperature difference coefficient, K2 is an ambient temperature coefficient, K3 is a sunlight influence coefficient, and T0 is a temperature compensation value. According to the target air outlet temperature T of the air blower B And the pipeline loss T corresponding to the heating mode L The formula is adopted: T C =T B +T L Acquiring a target air outlet temperature T of an internal air cooler in the vehicular heat pump system C .

5. The heating control method based on the vehicular heat pump system according to claim 3, characterized by, The determining of the compressor target rotating speed in the matched heating mode according to the actual air outlet temperature and the target air outlet temperature comprises: every preset time T, acquire a difference e(t) between the actual air outlet temperature and the target air outlet temperature at a current time t, and adopt a formula: Obtaining the compressor target rotating speed U(t) at the current time t; wherein, K p is a proportional coefficient, and U0 is a compressor rotating speed constant.

6. The heating control method based on a vehicular heat pump system according to claim 1 or 2, characterized by, The acquiring of the electronic expansion valve target opening degree in the matched heating mode according to the actual pressure of the vehicle heat pump system and a target pressure corresponding to the matched heating mode comprises: and adjusting the electronic expansion valve in the vehicle heat pump system according to the electronic expansion valve target opening degree comprises: acquire an actual discharge pressure of the compressor and a target discharge pressure of the compressor corresponding to the heating mode, and determine the electronic expansion valve target opening degree according to the actual discharge pressure and the target discharge pressure of the compressor; control the electronic expansion valve in the vehicle heat pump system to be adjusted according to the electronic expansion valve target opening degree.

7. The heating control method based on the vehicular heat pump system according to claim 6, characterized by, The determining of the electronic expansion valve target opening degree according to the actual discharge pressure and the target discharge pressure of the compressor comprises: every preset time T, acquire a difference f(t) between the actual discharge pressure and the target discharge pressure at a current time t, and adopt a formula: Obtaining the electronic expansion valve target opening degree V(t) at the current time t; wherein, K p is a proportional coefficient, and V0 is an electronic expansion valve opening constant.

8. An electronic control unit, characterized by comprise: a processor, a memory and a communication interface; the memory is used for storing executable instructions of the processor; wherein the processor is configured to execute the executable instructions to perform the heating control method based on the vehicle heat pump system according to any one of claims 1 to 7.

9. A new energy vehicle, characterized in that, comprise: the electronic control unit and the vehicle heat pump system according to claim 8.

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