Multi-temperature-zone air supply heat pump air conditioning system and control method thereof

Abstract

The invention discloses a multi-temperature-zone air supply heat pump air conditioning system and a control method thereof, and belongs to the technical field of electric automobile air conditioners. The system comprises a refrigerating system, an air supply system and an electric control unit. The refrigerating system comprises an inverter compressor, a liquid storage device, an outdoor heat exchanger, a heat regenerator and a four-way reversing valve. An outlet of the heat regenerator is connected with a first throttling device and a second indoor heat exchanger, and an outlet of the first throttling device is connected to the first indoor heat exchanger. The first indoor heat exchanger and the second indoor heat exchanger are connected to an air supply system; the air supply system comprises a fan, a first air supply outlet and a third air supply outlet; an inlet of the first indoor heat exchanger is connected with the third air supply outlet; an outlet of the first indoor heat exchanger is connected with the first air supply outlet and the second air supply outlet. According to the multi-temperature-zone air supply system, multiple kinds of different-temperature air supply are obtained through a pre-matched and designed double-heat-exchanger structure and middle throttling, temperature adjustment is further conducted through electric heating, and therefore multi-temperature-zone air supply is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of electric vehicle air conditioners and relates to a heat pump air conditioning system for multi-temperature zone air supply and a control method thereof. Background Art

[0002] At present, facing the problems of fossil energy shortage, greenhouse effect, environmental pollution, etc., pure electric vehicles have gradually entered people's lives as an effective solution. The use and promotion of electric vehicles is a powerful tool to promote energy conservation and emission reduction and achieve the "dual carbon" goal. Compared with fuel vehicles, electric vehicles have no engine waste heat to use, so the independent heat pump air conditioning system has become an indispensable part of the vehicle.

[0003] Ordinary automobile air conditioning systems use a single temperature to supply air, and simply distribute the air supply from the evaporator outlet to each air outlet of the car according to the air volume, without further adjusting the air supply temperature to each air outlet. Such an air supply system has a simple air path structure and is stable and reliable to use. However, from the perspective of occupant thermal comfort, due to the unevenness of the thermal environment in the passenger compartment and the differences in the physiological requirements of different passengers for the thermal environment, the air supply parameters required to achieve the most ideal thermal comfort conditions in different areas of the passenger compartment are not exactly the same. For the air outlets in different areas, using independent air supply parameters for air supply has become a necessity to achieve thermal comfort for occupants in each area of ​​the passenger compartment, improve the overall thermal comfort level of passengers, and achieve refined air supply control. By adopting multi-temperature air supply and zoned air supply control for automobile air conditioning, different air supply can be carried out for different passenger seating areas, thereby achieving different thermal environments and better adapting to the differentiated needs of different passengers for thermal comfort.

[0004] At present, the way that automobile air conditioners achieve multi-temperature zone air supply is generally to overcool the supply air and then reheat it, that is, the air at the outlet of the indoor heat exchanger is appropriately heated before being sent to each area, so as to control the supply air temperature to the required level. Although this method can achieve multi-temperature air supply regulation, and the implementation form and control method are relatively simple, it generally cools the supply air to the required minimum temperature, and then significantly heats the supply air that requires a relatively high temperature. This form does not regulate the system cooling capacity and energy distribution well, and there is a significant waste of cooling capacity, which reduces the efficiency of the entire multi-temperature zone air supply air conditioner.

[0005] Therefore, in order to improve energy utilization efficiency and minimize energy waste on the basis of achieving multi-temperature zone air supply, it is necessary to improve the air supply form and control method of air conditioning. Summary of the invention

[0006] The purpose of the present invention is to provide a heat pump air conditioning system with multi-temperature zone air supply and a control method thereof, so as to solve the technical problem in the prior art that the air conditioning air supply method of performing secondary heating of a single cold air to different degrees results in serious waste of cold energy, thereby reducing the efficiency of the entire multi-temperature zone air supply air conditioning.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a heat pump air conditioning system for multi-temperature zone air supply, comprising:

[0009] A refrigeration system, the refrigeration system comprising a variable frequency compressor, a liquid accumulator, an outdoor heat exchanger, a regenerator and a four-way reversing valve; the four interfaces of the four-way reversing valve are respectively connected to the variable frequency compressor, the outdoor heat exchanger, the regenerator and the liquid accumulator; the variable frequency compressor and the liquid accumulator are also directly connected through a pipeline; the outdoor heat exchanger and the regenerator are also directly connected through a pipeline; the outlet of the regenerator is respectively connected to a first throttling device and a second indoor heat exchanger, and the outlet of the first throttling device is connected to a first indoor heat exchanger; the first indoor heat exchanger and the second indoor heat exchanger are connected to an air supply system;

[0010] An air supply system, the air supply system comprising a fan, a first air supply port, a second air supply port and a third air supply port; the air generated by the fan passes through the second indoor heat exchanger and the first indoor heat exchanger in sequence; the inlet of the first indoor heat exchanger is connected to the third air supply port, and a third electric heater is arranged in the air duct of the third air supply port; the outlet of the first indoor heat exchanger is respectively connected to the first air supply port and the second air supply port; a first electric heater is arranged in the air duct of the first air supply port, and a second electric heater is arranged in the air duct of the second air supply port;

[0011] The electronic control unit is electrically connected to the control panel, the variable frequency compressor, the four-way reversing valve, the fan, the first electric heater, the second electric heater and the third electric heater respectively; the electronic control unit is used to control the inlet and outlet air temperatures of the first indoor heat exchanger and the second indoor heat exchanger according to the target temperature input by the control panel, and then perform secondary heating through the first electric heater, the second electric heater and the third electric heater to finally reach the preset target temperature value of each area.

[0012] Furthermore, the refrigeration system also includes a second throttling device; the second throttling device is located on the connecting pipe between the heat regenerator and the second indoor heat exchanger; the first throttling device and the second throttling device are both electrically connected to the electronic control unit.

[0013] Furthermore, a second damper is provided at the inlet of the first indoor heat exchanger for controlling the air volume entering the third air supply port; the second damper is electrically connected to the electronic control unit.

[0014] Furthermore, a first damper is provided at a branching point of a pipeline trunk connecting the first indoor heat exchanger to the first air supply port and the second air supply port respectively, for controlling the air volume entering the first air supply port and the second air supply port; the first damper is electrically connected to the electronic control unit.

[0015] Furthermore, the refrigeration system also includes an exhaust pressure sensor; the exhaust pressure sensor is located between the variable frequency compressor and the four-way reversing valve; the exhaust pressure sensor is electrically connected to the electronic control unit.

[0016] Furthermore, a first temperature sensor is provided at the inlet of the first indoor heat exchanger; a second temperature sensor is provided at the outlet of the first indoor heat exchanger; a third temperature sensor is installed at the air outlet of the first air supply outlet; a fourth temperature sensor is installed at the air outlet of the second air supply outlet; a fifth temperature sensor is installed at the air outlet of the third air supply outlet; the first temperature sensor, the second temperature sensor, the third temperature sensor, the fourth temperature sensor and the fifth temperature sensor are all electrically connected to the electronic control unit.

[0017] Furthermore, the fan is a variable frequency fan.

[0018] Furthermore, the refrigerant used in the refrigeration system is carbon dioxide.

[0019] In a second aspect, the present invention provides a control method for the heat pump air conditioning system with multi-temperature zone air supply, comprising the following steps:

[0020] The target temperature and air volume of each area are transmitted to the electronic control unit through the control panel, and the target air temperature of each area is determined according to the target temperature of each area, thereby determining the inlet and outlet air temperatures of the first indoor heat exchanger and the second indoor heat exchanger;

[0021] The electronic control unit receives the signal from the exhaust pressure sensor, detects the exhaust pressure of the variable frequency compressor, and controls the speed of the variable frequency compressor to make the exhaust pressure reach the target value;

[0022] The electronic control unit receives signals from the first temperature sensor and the second temperature sensor to detect the inlet and outlet air temperatures of the first indoor heat exchanger; the air-side heat exchange amount is obtained according to the target inlet and outlet air temperatures and air volumes of the first indoor heat exchanger and the second indoor heat exchanger, thereby determining the evaporation temperature of the refrigerant in the first indoor heat exchanger and the second indoor heat exchanger, and controlling the opening of the first throttling device and the second throttling device so that the evaporation temperature of the refrigerant in the first indoor heat exchanger and the second indoor heat exchanger reaches the target value, thereby making the inlet and outlet air temperature of the first indoor heat exchanger reach the target value;

[0023] The sum of the air supply volumes in each area is taken as the total air supply volume of the air supply system, and the total air supply volume of the air supply system is controlled to reach the target value by controlling the variable frequency fan;

[0024] The electronic control unit receives signals from the third temperature sensor, the fourth temperature sensor, and the fifth temperature sensor, detects the air supply temperature of the first air supply outlet, the second air supply outlet, and the third air supply outlet, and adjusts the air supply temperature of each area to a target value by controlling the power of the first electric heater, the second electric heater, and the third electric heater respectively;

[0025] According to the air supply volume ratio of each area, the air supply volume of different areas reaches the target value through the opening of the first air door and the second air door of the electronic control unit;

[0026] The electronic control unit receives the air conditioning mode setting signal from the control panel, controls the state of the four-way reversing valve, and realizes the switching between cooling mode and heating mode;

[0027] In cooling mode, the minimum supply air temperature of each area is set as the outlet air temperature target value of the first indoor heat exchanger; the maximum supply air temperature of each area is set as the inlet air temperature target value of the first indoor heat exchanger;

[0028] In the heating mode, the second maximum value of the supply air temperature in each area is set as the outlet air temperature target value of the first indoor heat exchanger; the minimum value of the supply air temperature in each area is set as the inlet air temperature target value of the first indoor heat exchanger.

[0029] Furthermore, it also includes: pre-matching and designing the two heat exchangers according to relevant parameters under the design operating conditions or actual operating conditions, and the specific steps are as follows:

[0030] Obtain the actual operating conditions or designed operating conditions of the automobile zone air conditioner, and obtain the user setting data under the corresponding conditions; for each group of conditions, calculate the target air supply temperature data of each air outlet, and arrange them from large to small as T1>T2>T3; combined with the inlet air temperature T in , the second indoor heat exchanger outlet air temperature T mid and the first indoor heat exchanger outlet air temperature T out ; By controlling the cooling capacity of the refrigeration system, the outlet air temperature of the first indoor heat exchanger reaches the minimum temperature T3 in the cooling mode, and the energy efficiency coefficient η is defined as:

[0031]

[0032] The outlet air temperature of the first indoor heat exchanger reaches the middle temperature value T2 in the heating mode, and the energy efficiency coefficient η is defined as:

[0033]

[0034] When the outlet air temperature of the second indoor heat exchanger is close to T1 in cooling mode and close to T3 in heating mode, the actual operating condition is close to the ideal condition, and the energy efficiency coefficient η approaches 1;

[0035] Divide the expected ambient temperature range into several areas according to the frequency of occurrence. <T env1 ,T env1 ~T env2 ,T env2 ~T env3 ,…,>T envn , according to the expected frequency of occurrence of each temperature range under actual operating conditions, a weight coefficient ω is assigned to it i ,ω i = frequency of current temperature range working condition / total number of environmental working conditions; get the comprehensive energy efficiency based on weight coefficient under all working conditions:

[0036] η a =∑ω i η i

[0037] By adjusting the opening of the second throttling device, the cooling capacity distribution of the first indoor heat exchanger and the second indoor heat exchanger is adjusted so that the outlet air temperature of the second indoor heat exchanger is T mid The limit is always kept below T1, which can meet the air supply needs of all working conditions and achieve the highest system energy efficiency.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] The present invention discloses a heat pump air conditioning system for multi-temperature zone air supply and a control method thereof. By pre-matching and designing a double heat exchanger (reasonably designing the size, dimensions, and heat exchange capacity of the two heat exchangers) and performing secondary throttling in the middle of the double heat exchanger, three different temperature air supply are obtained at the inlet, outlet, and middle section of the first indoor heat exchanger and the second indoor heat exchanger, and finally further temperature adjustment is performed by electric heating, thereby realizing multi-temperature air supply. Compared with the method of performing secondary heating to different degrees on a single cold air to obtain a plurality of different temperature air supply methods, this method makes the cooling capacity of the refrigeration system approximately match the cooling capacity required for air supply, and the required electric heating power is greatly reduced, thereby improving energy utilization efficiency and reducing energy waste. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0041] Figure 1 This is a schematic diagram of a multi-temperature zone air conditioning and air supply system for an electric vehicle according to an embodiment of the present invention;

[0042] Figure 2This is a control schematic diagram of a multi-temperature zone air conditioning air supply system for an electric vehicle according to an embodiment of the present invention.

[0043] Among them: 1. variable frequency compressor; 2. exhaust pressure sensor; 3. outdoor heat exchanger; 4. regenerator; 51. first throttling device; 52. second throttling device; 61. first indoor heat exchanger; 62. second indoor heat exchanger; 7. four-way reversing valve; 8. liquid storage tank; 9. variable frequency fan; 101. first damper; 102. second damper; 111. first electric heating; 112. second electric heating; 113. third electric heating; 121. first temperature sensor; 122. second temperature sensor; 123. third temperature sensor; 124. fourth temperature sensor; 125. fifth temperature sensor; 131. first air outlet; 132. second air outlet; 133. third air outlet; 14. electronic control unit; 15. control panel. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0045] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0047] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0048] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0049] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0050] The present invention is further described in detail below in conjunction with the accompanying drawings:

[0051] See also Figure 1 The embodiment of the present invention discloses a heat pump air conditioning system for multi-temperature zone air supply, including a refrigeration system, an air supply system and an electronic control unit 14. The refrigeration system includes a variable frequency compressor 1, a liquid storage device 8, an outdoor heat exchanger 3, a regenerator 4, a first throttling device 51, a first indoor heat exchanger 61, a second indoor heat exchanger 62 and a four-way reversing valve 7 connected by pipelines; the outlet of the regenerator 4 is respectively connected to the first throttling device 51 and the second indoor heat exchanger 62, and the outlet of the first throttling device 51 is connected to the first indoor heat exchanger 61; the first indoor heat exchanger 61 and the second indoor heat exchanger 62 are connected to the air supply system; the fan in the air supply system is sequentially connected to the second indoor heat exchanger 62 and the first indoor heat exchanger 61; the inlet of the first indoor heat exchanger 61 The wind is partially led out through the diverter damper 102 and then sent to the third air supply port 133. The air duct of the third air supply port 133 is provided with a third electric heater 113. The outlet wind of the first indoor heat exchanger 61 is divided by the diverter damper 101 and then sent to the first air supply port 131 and the second air supply port 132 respectively. The air duct of the first air supply port 131 is provided with a first electric heater 111, and the air duct of the second air supply port 132 is provided with a second electric heater 112. The air supply ports (131-133) are connected to the corresponding temperature zones of the passenger compartment, and the electric heaters (111-113) are arranged in the air duct to heat the supply air. Figure 2 The electronic control unit is electrically connected to the control panel 15, the variable frequency compressor 1, the four-way reversing valve 7, the fan, the first electric heater 111, the second electric heater 112 and the third electric heater 113. The control panel 15 is arranged in the passenger compartment and connected to the electronic control unit 14, and is used to input passenger setting data to the electronic control unit 14.

[0052] The refrigeration system and air supply system of this embodiment are configured with a dual heat exchanger structure to achieve dual inlet and outlet air temperature acquisition. The dual heat exchanger is pre-matched and designed according to the actual possible application environment conditions and user data conditions, so that the outlet air temperature limit can be achieved while giving full play to the heat exchanger capacity. At the same time, the evaporation temperature is controlled by intermediate throttling, so that the intermediate outlet air temperature of the heat exchanger can meet the air supply demand, while maximizing the system performance, and based on the distribution of higher outlet air temperatures that cannot be achieved by coordinated regulation of electric heating, the system comprehensive energy efficiency ratio is guaranteed to be the highest under the premise of ensuring the dual air supply demand.

[0053] In a feasible embodiment of the present invention, the refrigeration system also includes a second throttling device 52; the first throttling device 51 is located on the connecting pipe between the regenerator 4 and the first indoor heat exchanger 61; the second throttling device 52 is located on the connecting pipe between the regenerator 4 and the second indoor heat exchanger 62; the first throttling device 51 and the second throttling device 52 are both electrically connected to the electronic control unit 14, and the electronic control unit 14 can control the speed of the variable frequency compressor 1 and the opening of the first throttling device 51 and the second throttling device 52.

[0054] In a feasible embodiment of the present invention, a second damper 102 is provided at the inlet of the first indoor heat exchanger 61 for controlling the air volume entering the third air supply port 133; the second damper 102 is electrically connected to the electronic control unit 14. A first damper 101 is provided at the branching part of the pipeline trunk connecting the first indoor heat exchanger 61 with the first air supply port 131 and the second air supply port 132 respectively for controlling the air volume entering the first air supply port 131 and the second air supply port 132; the first damper 101 is electrically connected to the electronic control unit 14.

[0055] In a feasible embodiment of the present invention, the refrigeration system further includes an exhaust pressure sensor 2 ; the exhaust pressure sensor 2 is located between the variable frequency compressor 1 and the four-way reversing valve 7 ; the exhaust pressure sensor 2 is electrically connected to the electronic control unit 14 .

[0056] In a feasible embodiment of the present invention, a first temperature sensor 121 is provided at the inlet of the first indoor heat exchanger 61; a second temperature sensor 122 is provided at the outlet of the first indoor heat exchanger 61; a third temperature sensor 123 is installed at the outlet of the first air supply port 131; a fourth temperature sensor 124 is installed at the outlet of the second air supply port 132; a fifth temperature sensor 125 is installed at the outlet of the third air supply port; the first temperature sensor 121, the second temperature sensor 122, the third temperature sensor 123, the fourth temperature sensor 124 and the fifth temperature sensor 125 are all electrically connected to the electronic control unit 14. The temperature sensor is arranged in the air duct of the air supply system to detect the air temperature at each position;

[0057] In a feasible embodiment of the present invention, preferably, the fan is preferably a variable frequency fan 9; the refrigeration system uses carbon dioxide as a refrigerant, and realizes heat exchange with the air supply of the air supply system through the first indoor heat exchanger 61 and the second indoor heat exchanger 62; heat exchange is performed between the high pressure section and the low pressure section of the regenerator 4;

[0058] The embodiment of the present invention discloses a control method for a heat pump air conditioning system with multi-temperature zone air supply, which specifically includes:

[0059] The control panel 15 reads the target temperature and air volume of each area input by the user and sends them to the electronic control unit 14. The air temperature of each area is determined according to the target temperature of each area, and then the target value of the inlet and outlet air temperature of the first indoor heat exchanger 61 is determined.

[0060] The electronic control unit 14 receives the signal of the exhaust pressure sensor 2, detects the exhaust pressure of the variable frequency compressor 1, and controls the speed of the variable frequency compressor 1 to make the exhaust pressure reach the target value.

[0061] The electronic control unit 14 receives signals from the first temperature sensor 121 and the second temperature sensor 122, detects the inlet and outlet air temperatures of the first indoor heat exchanger 61, obtains the wind-side heat exchange amount according to the inlet and outlet target air temperatures and air volume of the first indoor heat exchanger 51, thereby determining the evaporation temperature of the refrigerant in the first indoor heat exchanger 61 and the second indoor heat exchanger 62, and controls the opening of the first throttling device 51 and the second throttling device so that the evaporation temperature of the refrigerant in the first indoor heat exchanger 61 and the second indoor heat exchanger 62 reaches the target value, thereby making the inlet and outlet air temperatures of the first indoor heat exchanger 61 reach the target value.

[0062] The sum of the air supply volumes of each area is taken as the total air supply volume of the air supply system, and the total air supply volume of the air supply system is controlled to reach the target value by controlling the variable frequency fan 9.

[0063] The electronic control unit 14 receives the supply air temperature setting value signal of each area of ​​the control panel 15, and receives the signals of the third temperature sensor 123, the fourth temperature sensor 124, and the fifth temperature sensor 125, detects the supply air temperature of the first air supply outlet 131, the second air supply outlet 132, and the third air supply outlet 133, and uses the supply air temperature as the control target to control the heating power of the first electric heater 111, the second electric heater 112, and the third electric heater 113, and adjusts the supply air temperature of the air supply outlet to the target value by changing the electric heating power.

[0064] The electronic control unit 14 receives the air supply volume signals of each area from the control panel 15, and adjusts the openings of the first damper 101 and the second damper 102 according to the air supply volume ratio of each area, so that the air supply volume of different areas reaches the target value.

[0065] The electronic control unit 14 receives the air conditioning mode setting signal from the control panel 15 and controls the state of the four-way reversing valve 7 to switch between the cooling mode and the heating mode.

[0066] It should be noted that the target value of the outlet air temperature of the first indoor heat exchanger 61 is set to the minimum value of the air supply temperature of each area in the cooling mode; and is set to the second maximum value of the air supply temperature of each area in the heating mode. The target value of the inlet air temperature of the first indoor heat exchanger 61 is set to the maximum value of the air supply temperature of each area in the cooling mode; and is set to the minimum value of the air supply temperature of each area in the heating mode.

[0067] It should be noted that, for each air supply route to the passenger compartment, the openings of the first air door 101 and the second air door 102 are determined according to the air volume required for each air supply route.

[0068] The opening degree of the first air door 101 is determined according to the ratio of the air volume required by the first air supply port 131 and the second air supply port 132 .

[0069] The opening degree of the second air door 102 is determined according to the proportion of the third air outlet 133 in the total air volume.

[0070] In summary, the present invention obtains multi-temperature air supply by means of dual heat exchanger air induction, and adjusts the temperature by electric heating. Compared with the secondary heating of a single cold air to different degrees, a plurality of different temperature air supply modes are obtained. In this mode, the cooling capacity of the refrigeration system is approximately matched with the cooling capacity required for air supply, and the required electric heating power is greatly reduced, thereby improving energy utilization efficiency and reducing energy waste. The electric vehicle zoned air conditioning air supply system provided by the present invention is calculated and analyzed under typical working conditions. Compared with electric heating, its energy consumption can be reduced by about 10% to 20% under the same conditions, which has significant economic and environmental benefits, and has made significant contributions to environmental protection, alleviating the fossil energy crisis, and achieving carbon neutrality and carbon peak.

[0071] The working principle of the present invention is as follows:

[0072] The air supply system generates supply air through the variable frequency fan 9, and is connected to the first indoor heat exchanger 61 and the second indoor heat exchanger 62 for heat exchange. Part of the supply air is led out through the first damper 101 and the second damper 102 at the outlet and inlet of the first indoor heat exchanger 61 respectively. After the temperature is adjusted by electric heating, the required temperature supply air is finally obtained at the air supply port and delivered to the corresponding area of ​​the passenger compartment through the air supply port.

[0073] Temperature sensors are respectively arranged at the air supply outlets of each area and the inlet and outlet of the first indoor heat exchanger 61 for detecting the air supply temperature at the inlet and outlet of each air supply outlet and the first indoor heat exchanger 61 and sending the detection results to the electronic control unit 14 .

[0074] The electronic control unit 14 is used to determine the air temperature of each area according to the detection signal of the temperature sensor, and receive the signal of the control panel 15, input the control signal according to the preset control method, and realize the matching of the air supply temperature and air supply volume of each area with the target signal of the control panel by controlling the refrigeration system and the air supply system.

[0075] In order to obtain the outlet air temperature that meets the actual operating conditions and improve the heat exchanger efficiency and the overall energy efficiency of the system, the two heat exchangers are pre-matched and designed according to the relevant parameters under the design conditions or actual operating conditions. The method is as follows:

[0076] The actual operating condition or designed operating condition environmental parameters of the automobile zone air conditioner are obtained by measuring the target environment, analyzing the climate and driving data, and obtaining the user setting data under the corresponding working condition by analyzing the user habit data. For each set of working conditions, the target air supply temperature data of each air outlet is calculated according to the corresponding data, and arranged from large to small as T1>T2>T3, combined with the inlet air temperature T in , the outlet air temperature of the second indoor heat exchanger 62 is T mid , the outlet air temperature of the first indoor heat exchanger 61 is T out By controlling the cooling capacity of the refrigeration system, the outlet air temperature of the first indoor heat exchanger 61 reaches the minimum target air supply temperature T3 of each air supply outlet (the middle value T2 in the heating mode), that is, T out ≈T3(cooling) or T out ≈T2(heating), define the energy efficiency coefficient η:

[0077]

[0078] When the mode is heating, the above formula becomes:

[0079]

[0080] When the outlet air temperature of the second indoor heat exchanger 62 is T mid When it is close to T1 (the heating mode is T3), the actual operating condition is close to the ideal condition, and the energy efficiency coefficient η approaches 1. According to the temperature limit and temperature difference limit of the outlet air temperature of the second indoor heat exchanger 62 required under various actual conditions, by changing the size, structure, number of flow channels and other parameters of the first indoor heat exchanger 61 and the second indoor heat exchanger 62, the heat exchange capacity ratio of the two heat exchangers is changed, so as to meet the outlet air temperature T of the second indoor heat exchanger 62 under different actual operating conditions or designed operating conditions. mid Do not exceed T1 (T3 in heating mode) and maximize the energy efficiency coefficient η.

[0081] By statistically analyzing the environmental parameters and user setting data under a large number of reference conditions, the application environment and user condition bias of the automotive zone air conditioner are obtained. The possible ambient temperature range is divided into several areas according to the frequency of occurrence, such as " <T env1 ,T env1 ~T env2 ,T env2 ~T env3 ,…,>T envn ", according to the possible frequency of occurrence of each temperature range under actual operating conditions, a weight coefficient ω is assigned to it i , that is, ω i =Frequency of current temperature range working condition / total number of environmental working conditions. For different user settings under each environmental working condition, weighting is performed in the same way. Finally, the comprehensive energy efficiency based on weight coefficient under all working conditions is obtained:

[0082] η a =∑ω i η i

[0083] Under the condition that the intermediate outlet temperature limit of the heat exchanger and the outlet temperature difference limit of the heat exchanger are met, the comprehensive energy efficiency of all working conditions is maximized, thereby obtaining the optimal heat exchanger matching design. At the same time, by adjusting the opening of the second throttling device 52, the cooling capacity distribution of the first indoor heat exchanger 61 and the second indoor heat exchanger 62 is adjusted so that the outlet air temperature T mid The limit is always kept below T1, which means that the air supply needs of all working conditions can be met, while at the same time the required electric heating power is reduced as much as possible, making the system most energy efficient.

[0084] The four-way reversing valve 7 is used to switch the working mode of the refrigeration system, and has two states, corresponding to the cooling mode and the heating mode respectively.

[0085] The air supply system supplies air to the passenger compartment in each route, controls the refrigeration system according to the target temperature, so that the air inlet and outlet of the first indoor heat exchanger 61 reaches a temperature close to the preset temperature, and adjusts the temperature through electric heating.

[0086] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A heat pump air conditioning system for multi-temperature zone air supply, characterized in that: include: A refrigeration system, the refrigeration system comprising a variable frequency compressor (1), a liquid accumulator (8), an outdoor heat exchanger (3), a regenerator (4) and a four-way reversing valve (7); the four interfaces of the four-way reversing valve (7) are respectively connected to the variable frequency compressor (1), the outdoor heat exchanger (3), the regenerator (4) and the liquid accumulator (8); the variable frequency compressor (1) and the liquid accumulator (8) are also directly connected via a pipeline; the outdoor heat exchanger (3) and the regenerator (4) are also directly connected via a pipeline; the outlet of the regenerator (4) is respectively connected to a first throttling device (51) and a second indoor heat exchanger (62), and the outlet of the first throttling device (51) is connected to the first indoor heat exchanger (61); the first indoor heat exchanger (61) and the second indoor heat exchanger (62) are connected to an air supply system; An air supply system, the air supply system comprising a fan, a first air supply port (131), a second air supply port (132) and a third air supply port (133); the air generated by the fan passes through the second indoor heat exchanger (62) and the first indoor heat exchanger (61) in sequence; the inlet of the first indoor heat exchanger (61) is connected to the third air supply port (133), and a third electric heater (113) is arranged in the air duct of the third air supply port (133); the outlet of the first indoor heat exchanger (61) is respectively connected to the first air supply port (131) and the second air supply port (132); the first electric heater (111) is arranged in the air duct of the first air supply port (131), and the second electric heater (112) is arranged in the air duct of the second air supply port (132); An electric control unit (14) is electrically connected to a control panel (15), a variable frequency compressor (1), a four-way reversing valve (7), a fan, a first electric heater (111), a second electric heater (112) and a third electric heater (113) respectively; the electric control unit (14) is used to control the inlet and outlet air temperatures of the first indoor heat exchanger (61) and the second indoor heat exchanger (62) according to a target temperature input by the control panel (15), and then perform secondary heating through the first electric heater (111), the second electric heater (112) and the third electric heater (113), so as to finally reach a preset target temperature value for each area.

2. A heat pump air conditioning system with multi-temperature zone air supply according to claim 1, characterized in that: The refrigeration system also includes a second throttling device (52); the second throttling device (52) is located on the connecting pipe between the regenerator (4) and the second indoor heat exchanger (62); the first throttling device (51) and the second throttling device (52) are both electrically connected to the electronic control unit (14).

3. A heat pump air conditioning system with multi-temperature zone air supply according to claim 1, characterized in that: A second damper (102) is provided at the inlet of the first indoor heat exchanger (61) for controlling the amount of air entering the third air supply port (133); the second damper (102) is electrically connected to the electronic control unit (14).

4. A heat pump air conditioning system with multi-temperature zone air supply according to claim 1, characterized in that: A first damper (101) is provided at the branching point of the pipeline main line connecting the first indoor heat exchanger (61) with the first air supply port (131) and the second air supply port (132) respectively, for controlling the air volume entering the first air supply port (131) and the second air supply port (132); the first damper (101) is electrically connected to the electronic control unit (14).

5. The heat pump air conditioning system for multi-temperature zone air supply according to claim 1, characterized in that: The refrigeration system further comprises an exhaust pressure sensor (2); the exhaust pressure sensor (2) is located between the variable frequency compressor (1) and the four-way reversing valve (7); and the exhaust pressure sensor (2) is electrically connected to the electronic control unit (14).

6. A heat pump air conditioning system with multi-temperature zone air supply according to claim 1, characterized in that: A first temperature sensor (121) is provided at the inlet of the first indoor heat exchanger (61); a second temperature sensor (122) is provided at the outlet of the first indoor heat exchanger (61); a third temperature sensor (123) is installed at the air outlet of the first air supply port (131); a fourth temperature sensor (124) is installed at the air outlet of the second air supply port (132); and a fifth temperature sensor (125) is installed at the air outlet of the third air supply port; the first temperature sensor (121), the second temperature sensor (122), the third temperature sensor (123), the fourth temperature sensor (124) and the fifth temperature sensor (125) are all electrically connected to the electronic control unit (14).

7. The heat pump air conditioning system for multi-temperature zone air supply according to claim 1, characterized in that: The fan is a variable frequency fan (9).

8. The heat pump air conditioning system with multi-temperature zone air supply according to claim 1, characterized in that: The refrigerant used in the refrigeration system is carbon dioxide.

9. A control method for a heat pump air conditioning system with multi-temperature zone air supply according to any one of claims 2 to 8, characterized in that: The following steps are involved: The target temperature and air supply volume of each area are transmitted to the electric control unit (14) through the control panel (15), and the target air supply temperature of each area is determined according to the target temperature of each area, thereby determining the inlet and outlet air temperatures of the first indoor heat exchanger (61) and the second indoor heat exchanger (62); The electronic control unit (14) receives a signal from an exhaust pressure sensor (2), detects the exhaust pressure of the variable frequency compressor (1), and controls the rotation speed of the variable frequency compressor (1) so that the exhaust pressure reaches a target value; The electronic control unit (14) receives signals from the first temperature sensor (121) and the second temperature sensor (122) to detect the inlet and outlet air temperatures of the first indoor heat exchanger (61); the air-side heat exchange amount is obtained according to the target inlet and outlet air temperatures and air volumes of the first indoor heat exchanger (61) and the second indoor heat exchanger (62), thereby determining the evaporation temperature of the refrigerant in the first indoor heat exchanger (61) and the second indoor heat exchanger (62); and the opening of the first throttling device (51) and the second throttling device (52) is controlled so that the evaporation temperature of the refrigerant in the first indoor heat exchanger (61) and the second indoor heat exchanger (62) reaches the target value, thereby making the inlet and outlet air temperatures of the first indoor heat exchanger (61) reach the target value; The sum of the air supply volumes of each area is taken as the total air supply volume of the air supply system, and the total air supply volume of the air supply system is controlled to reach a target value by controlling the variable frequency fan (9); The signals of the third temperature sensor (123), the fourth temperature sensor (124) and the fifth temperature sensor (125) are received through the electric control unit (14), the air supply temperature of the first air supply port (131), the second air supply port (132) and the third air supply port (133) is detected, and the air supply temperature of each area is adjusted to a target value by controlling the power of the first electric heater (111), the second electric heater (112) and the third electric heater (113) respectively; According to the air supply volume ratio of each area, the air supply volume of different areas reaches the target value through the opening of the first air door (101) and the second air door (102) of the electric control unit (14); An air conditioning mode setting signal is received from a control panel (15) via an electronic control unit (14), and the state of a four-way reversing valve (7) is controlled to achieve switching between a cooling mode and a heating mode; In cooling mode, the minimum air supply temperature of each zone is set as the outlet air temperature target value of the first indoor heat exchanger (61); the maximum air supply temperature of each zone is set as the inlet air temperature target value of the first indoor heat exchanger (61); In the heating mode, the second maximum value of the supply air temperature in each zone is set as the outlet air temperature target value of the first indoor heat exchanger (61); and the minimum value of the supply air temperature in each zone is set as the inlet air temperature target value of the first indoor heat exchanger (61).

10. The control method of a heat pump air conditioning system with multi-temperature zone air supply according to claim 9, characterized in that: Also includes: According to the relevant parameters under the design operating conditions or actual operating conditions, the two heat exchangers are pre-matched and designed. The specific steps are as follows: The actual operating condition or the designed operating condition environmental parameters of the automobile zone air conditioner are obtained, and the user setting data under the corresponding operating condition is obtained; for each group of operating conditions, the target air supply temperature data of each air supply outlet is calculated and arranged from large to small as T1>T2>T3; combined with the inlet air temperature T in , the outlet air temperature of the second indoor heat exchanger (62) T mid and the outlet air temperature T of the first indoor heat exchanger (61) out ; By controlling the cooling capacity of the refrigeration system, the outlet air temperature of the first indoor heat exchanger (61) reaches the minimum temperature T3 in the refrigeration mode, and the energy efficiency coefficient η is defined as: When the outlet air temperature of the first indoor heat exchanger (61) reaches the intermediate temperature value T2 in the heating mode, the energy efficiency coefficient η is defined as: When the outlet air temperature of the second indoor heat exchanger (62) is close to T1 in cooling mode and close to T3 in heating mode, the actual operating condition is close to the ideal condition, and the energy efficiency coefficient η approaches 1; Divide the expected ambient temperature range into several areas according to the frequency of occurrence. <T env1 ,T env1 ~T env2 ,T env2 ~T env3 ,…,>T envn , according to the expected frequency of occurrence of each temperature range under actual operating conditions, a weight coefficient ω is assigned to it i ,ω i = frequency of current temperature range working condition / total number of environmental working conditions; get the comprehensive energy efficiency based on weight coefficient under all working conditions: or a =∑ωη i By adjusting the opening of the second throttling device (52), the cooling capacity distribution of the first indoor heat exchanger (61) and the second indoor heat exchanger (62) is adjusted so that the outlet air temperature T mid The limit is always kept below T1, which can meet the air supply needs of all working conditions and achieve the highest system energy efficiency.

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