New energy vehicle waste heat recovery device and recovery method thereof

Abstract

The invention provides a new energy vehicle waste heat recovery device and method, and relates to the technical field of vehicle power motor cooling devices.The new energy vehicle waste heat recovery device is characterized in that the interior of a shell of a hydrogen-helium heat exchanger is divided into a first heat exchange cavity and a second heat exchange cavity through two partition plates, and a tube plate is arranged between the partition plates; the hydrogen heat exchange tube penetrates through the first heat exchange cavity and then is led out from the tube plate to form a loop; the helium heat exchange tube penetrates through the second heat exchange cavity to form a loop after being introduced from the tube plate; the hydrogen heat exchange tubes and the helium heat exchange tubes are staggered, and the linear length of the hydrogen heat exchange tubes and the helium heat exchange tubes on the tube plate is 30-50 mm; the first heat exchange cavity communicates with the motor assembly, the second heat exchange cavity communicates with the air conditioner heating assembly, a three-way electromagnetic valve is arranged on a pipeline of the air conditioner heating assembly, and the heat dissipation assembly is connected with the air conditioner heating assembly in parallel through the three-way electromagnetic valve. The problems that in the prior art, the heat dissipation effect is poor, and waste heat energy is wasted are solved, and the technical effects that the power motor is rapidly cooled, heat is efficiently exchanged, waste heat is recycled into an air conditioning system, and energy is reused are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle power motor cooling devices, and in particular to a waste heat recovery device for a new energy vehicle and a recovery method thereof. Background Art

[0002] In new energy vehicles, the power motor will generate a lot of heat during operation. If it cannot be cooled effectively and in a timely manner, the motor temperature will continue to rise, which will not only lead to a decline in motor performance and shorten its service life, but may also cause safety hazards.

[0003] At present, most of the cooling systems for power motors of new energy vehicles directly use ordinary tubular aluminum alloy radiators. The cooling medium flows in the tubular radiator, exchanges heat with the outside air through the tube wall, takes away the heat generated by the motor, and discharges it directly, and the waste heat is not utilized. In addition, the heat source of the air-conditioning system of new energy vehicles is relatively single, relying only on PTC heating. During the operation of the vehicle, the heat exchanger and PCT heating are independent of each other, so there is no correlation between the two.

[0004] Therefore, the existing power motor waste heat and air conditioning heat sources in new energy vehicles have the following problems: 1. In the cooling of the power motor, ordinary tubular aluminum alloy radiators are directly used to discharge heat out of the vehicle. The heat exchange efficiency of the radiator is limited, and it is impossible to quickly and stably dissipate the heat generated by the motor, and the waste heat is not recovered.

[0005] 2. In terms of heat recovery, new energy vehicles do not recycle the waste heat generated by the power motor heat exchanger into the air conditioning system, and a large amount of waste heat is directly discharged to the outside, resulting in energy waste. This not only increases the energy consumption of the vehicle, but also makes the air conditioning system completely dependent on PTC heating when heating, consuming too much electricity and reducing the vehicle's cruising range. Summary of the invention

[0006] The purpose of the present invention is to provide a waste heat recovery device and a recovery method for new energy vehicles, so as to alleviate the technical problems in the prior art that the heat dissipation effect of directly using a radiator is poor and the waste heat is not applied to the air-conditioning system, resulting in energy waste.

[0007] The present invention provides a waste heat recovery device for new energy vehicles, comprising: a hydrogen-helium heat exchanger, a motor assembly, an air conditioning heating assembly, a heat dissipation assembly and a three-way solenoid valve; The hydrogen-helium heat exchanger comprises a shell, a partition, a first heat exchange cavity, a second heat exchange cavity, a tube sheet, a hydrogen heat exchange tube and a helium heat exchange tube; The inside of the shell is separated into a first heat exchange cavity and a second heat exchange cavity by two partitions, and a tube sheet is arranged between the two partitions; the hydrogen heat exchange tube passes through the first heat exchange cavity and is led out from the tube sheet to form a loop; the helium heat exchange tube is introduced from the tube sheet and passes through the second heat exchange cavity to form a loop, the hydrogen heat exchange tube and the helium heat exchange tube are staggered, and the straight length of the hydrogen heat exchange tube and the helium heat exchange tube on the tube sheet is 30mm to 50mm; The first heat exchange chamber is connected to the motor component, and the second heat exchange chamber is connected to the air conditioning heating component. A three-way solenoid valve is also provided on the pipeline of the air conditioning heating component, and the heat dissipation component is connected in parallel with the air conditioning heating component through the three-way solenoid valve.

[0008] Furthermore, the hydrogen heat exchange tube passing through the first heat exchange cavity section and the helium heat exchange tube passing through the second heat exchange cavity section are both spiral.

[0009] Furthermore, the motor assembly includes a power motor and a first water pump; the first water pump is arranged in the water outlet pipeline of the power motor, the first water pump is connected to the inlet end of the first heat exchange chamber, and the outlet end of the first heat exchange chamber is connected to the water inlet pipeline of the power motor to form a loop.

[0010] Furthermore, the air conditioning heating component includes a warm air water pump, a water heating PTC, and an air conditioning warm air core; the warm air water pump, the water heating PTC and the air conditioning warm air core are arranged in sequence along the water flow direction on the outlet end pipeline of the second heat exchange chamber; the outlet end of the air conditioning warm air core is connected to the inlet end of the second heat exchange chamber to form a loop; the three-way solenoid valve is arranged in the upstream pipeline of the warm air water pump.

[0011] Furthermore, the heat dissipation component includes a radiator, a fan, and a second water pump; one side of the inlet end of the radiator is connected to the three-way solenoid valve, and one side of the outlet end of the radiator is connected to the upstream pipeline of the second water pump; the air outlet of the fan faces the radiator.

[0012] Furthermore, a plurality of temperature sensors are arranged on the pipeline connecting the second heat exchange chamber and the air conditioning heating component.

[0013] Furthermore, the radiator is a tubular radiator or an evaporative radiator.

[0014] The present invention also provides a method for recovering waste heat from a new energy vehicle, which method uses the above-mentioned waste heat recovery device for a new energy vehicle and comprises the following steps: Step 1: The hot water flowing out of the motor assembly flows through the first heat exchange chamber to transfer the waste heat to the hydrogen in the hydrogen heat exchange tube, and then cools down and flows back to the motor assembly; Step 2: The hydrogen in the hydrogen heat exchange tube conducts heat with the helium in the helium heat exchange tube to exchange heat energy; the helium in the helium heat exchange tube then flows through the cold water at the outlet end of the adjusted heating component to be heated; Step 3: When the heated water flows through the three-way solenoid valve, the three-way solenoid valve compares the heat Q1 generated by the motor component and the heat Q2 required by the air-conditioning heating component. The three-way solenoid valve then switches the flow direction and transfers the waste heat to the air-conditioning heating component, completing the waste heat recovery of the new energy vehicle.

[0015] Furthermore, the switching method of the flow direction switching of the three-way solenoid valve in step 3 is: When the heat of Q1 is less than the heat of Q2 and the speed of the motor component is greater than 0, the air conditioning heating component heats itself, closes the valve on one side of the air conditioning heating component, opens one side of the heat dissipation component, and dissipates heat; When the heat of Q1 is greater than or equal to the heat of Q2, the solenoid valve PID control method is used to determine whether Q2 has excess heat, and when heat is not needed, the valve on one side of the heat dissipation component is opened; When heat is needed, the valve on one side of the heat dissipation component is closed, and the valve opening on one side of the air-conditioning heating component is opened and controlled, and the water after heat conduction is used to heat the air-conditioning heating component 3 to complete the waste heat recovery of the new energy vehicle.

[0016] Furthermore, the solenoid valve PID control method uses a position PID and an incremental PID in parallel as an outer loop to calculate the target opening of the solenoid valve, and then connects the outer loop and the inner loop of the incremental PID in series to calculate the final opening of the solenoid valve; The position PID calculation formula in the outer loop is: (1); Among them, u(k) is the control output at the kth moment; Kp is the proportional coefficient; e(k) is the error value (Q1-Q2) at the kth moment; Ki is the integral coefficient; Ki×∑e(k) is the cumulative sum of all errors from the beginning to the kth moment, and Kd is the differential coefficient; The incremental PID calculation formula in the outer loop or inner loop is: (2); Among them, Δu(k) is the increment of the control quantity at the kth moment; Kp, Ki, Kd and e(k) are the same as those in the position PID; e(k-1) is the error value at the k-1th moment, and e(k-2) is the error value at the k-2th moment.

[0017] Beneficial effects: The present invention provides a waste heat recovery device for a new energy vehicle and a recovery method thereof, comprising a hydrogen-helium heat exchanger, wherein the interior of a shell of the hydrogen-helium heat exchanger is separated into a first heat exchange chamber and a second heat exchange chamber by two partitions, and a tube sheet is arranged between the two partitions; a hydrogen heat exchange tube and a helium heat exchange tube are staggered, and the straight lengths of the hydrogen heat exchange tube and the helium heat exchange tube on the tube sheet are 30 mm to 50 mm, and the hydrogen heat exchange tube passes through the first heat exchange chamber and is led out from the tube sheet to form a loop; the helium heat exchange tube is introduced from the tube sheet and passes through the second heat exchange chamber to form a loop; the first heat exchange chamber is connected to a motor assembly, and the second heat exchange chamber is connected to an air-conditioning heating assembly, and a three-way solenoid valve is also arranged on the pipeline of the air-conditioning heating assembly, and the heat dissipation assembly is connected in parallel with the air-conditioning heating assembly through the three-way solenoid valve.

[0018] Through the hydrogen-helium heat exchanger, the heat conduction effect between hydrogen and helium can be used to achieve efficient heat exchange from high-temperature hydrogen to low-temperature helium, quickly reduce the temperature of the power motor, improve the motor performance, and transfer waste heat to the helium. The helium side is connected to the air-conditioning heating component, which can recover the waste heat to the air-conditioning system, reduce vehicle energy consumption, and realize the reuse of waste heat from new energy vehicles. In addition, by setting a three-way solenoid valve on the air-conditioning heating component pipeline and connecting the heat dissipation component in parallel, the waste heat flow can be flexibly controlled according to the actual heat demand. When the air-conditioning does not need heat, the waste heat can be discharged outside the vehicle through the heat dissipation component; when the air-conditioning needs heat, the heat dissipation component is closed and the heat is transferred to the air-conditioning system to improve energy utilization efficiency.

[0019] In summary, the present invention can not only improve the heat dissipation effect of new energy vehicles, but also recycle the original waste heat directly discharged into the air-conditioning system; and according to the opening of the solenoid valve in the method, it can be stably transported. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 A schematic diagram of the structure of a waste heat recovery device for a new energy vehicle provided by an embodiment of the present invention; Figure 2 A schematic diagram of the structure of a hydrogen-helium heat exchanger in a waste heat recovery device for a new energy vehicle provided in an embodiment of the present invention; Figure 3 A flow chart of a method for recovering waste heat from a new energy vehicle provided by an embodiment of the present invention; Figure 4A switching logic diagram of a three-way solenoid valve in a waste heat recovery method for a new energy vehicle provided by an embodiment of the present invention; Figure 5 This is a flow chart of the solenoid valve PID control method in the new energy vehicle waste heat recovery method provided by an embodiment of the present invention.

[0022] Icons: 1-Hydrogen-helium heat exchanger; 101-shell; 102-partition; 103-first heat exchange chamber; 104-second heat exchange chamber; 105-tube sheet; 106-hydrogen heat exchange tube; 107-helium heat exchange tube; 2-motor assembly; 201-power motor; 202-first water pump; 3-air conditioning heating assembly; 301-warm air water pump; 302-water heating PTC; 303-air conditioning warm air core; 4-heat dissipation assembly; 401-radiator; 402-fan; 403-second water pump; 5-three-way solenoid valve; 6-temperature sensor. DETAILED DESCRIPTION

[0023] 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.

[0024] 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.

[0025] 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.

[0026] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the product of the invention is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0027] In addition, the terms "horizontal", "vertical", "overhanging" and the like do not mean that the components are required to be absolutely horizontal or overhanging, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0028] In the description 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 communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0030] like Figure 1 , Figure 2 As shown, the present invention provides a waste heat recovery device for new energy vehicles, comprising: a hydrogen-helium heat exchanger 1, a motor assembly 2, an air conditioning heating assembly 3, a heat dissipation assembly 4 and a three-way solenoid valve 5; The hydrogen-helium heat exchanger 1 comprises a shell 101, a partition 102, a first heat exchange cavity 103, a second heat exchange cavity 104, a tube sheet 105, a hydrogen heat exchange tube 106 and a helium heat exchange tube 107; The interior of the shell 101 is separated into a first heat exchange chamber 103 and a second heat exchange chamber 104 by two partitions 102, and the tube sheet 105 is arranged between the two partitions 102; the hydrogen heat exchange tubes and the helium heat exchange tubes are staggered, and the straight lengths of the hydrogen heat exchange tubes and the helium heat exchange tubes on the tube sheet are 30 mm to 50 mm. The hydrogen heat exchange tube 106 passes through the first heat exchange chamber 103 and is led out from the tube sheet 105 to form a loop; the helium heat exchange tube 107 is introduced from the tube sheet 105 and passes through the second heat exchange chamber 104 to form a loop; The first heat exchange chamber 103 is connected to the motor assembly 2, and the second heat exchange chamber 104 is connected to the air conditioning heating assembly 3. A three-way solenoid valve 5 is also provided on the pipeline of the air conditioning heating assembly 3, and the heat dissipation assembly 4 is connected in parallel with the air conditioning heating assembly 3 through the three-way solenoid valve 5.

[0031] Specifically, the hydrogen-helium heat exchanger 1 is used as a heat exchange part connecting the two ends of the loop, such as Figure 2As shown, a group of water inlets and water outlets are respectively provided at both ends, and two partitions 102 separate the interior of the shell 101 into a first heat exchange chamber 103 and a second heat exchange chamber 104; so that the hot water discharged from the motor assembly 2 enters the first heat exchange chamber 103 and is discharged after being absorbed by the hydrogen heat exchange tube 106; similarly, the helium heat exchange tube 107 absorbs the heat in the hydrogen heat exchange tube 106 and heats the fluid flowing back from the air conditioning heating assembly 3 at the other end. The cavity between the two partitions 102 is provided with a tube sheet 105. Two holes are provided between the two partitions 102 for the hydrogen heat exchange tube 106 and the helium heat exchange tube 107 to penetrate and be arranged on the tube sheet 105; the tube sheet 105 is usually made of high-strength, corrosion-resistant carbon steel material or aluminum alloy material, and holes for the hydrogen heat exchange tube 106 and the helium heat exchange tube 107 are distributed on the tube sheet 105. The hydrogen heat exchange tubes 106 and the helium heat exchange tubes 107 are arranged in a staggered manner on the tube sheet 105, thereby maximizing the contact area and time of the two gases during the heat exchange process.

[0032] The tube wall of the hydrogen heat exchange tube 106 has good thermal conductivity and can absorb the heat in the first heat exchange cavity 103. After passing through the first heat exchange cavity 103, the hydrogen heat exchange tube 106 is led out from the other side of the tube sheet 105 and forms a closed loop. In this loop, hydrogen absorbs heat to achieve effective transfer of high-temperature water heat discharged from the motor assembly 2. The layout of the helium heat exchange tube 107 cooperates with the hydrogen heat exchange tube 106. The helium heat exchange tube 107 also has excellent thermal conductivity and can transfer the absorbed heat to the second heat exchange cavity 104. After passing through the second heat exchange cavity 104, the helium heat exchange tube 107 also forms an independent closed loop, in which helium circulates and continuously exchanges heat.

[0033] It should be noted that the staggered shape of the hydrogen heat exchange tube 106 and the helium heat exchange tube 107 on the tube sheet 105 can be a staggered shape of a broken line (such as Figure 2 As shown in the figure) or spiral staggered (DNA shape) or other shapes, so that the two heat exchange tubes can maximize the contact between each other and conduct heat conduction from hydrogen to helium. The straight line length of each fold on the tube sheet 105 is 30mm to 50mm, that is, the contact length of the two is maximized in the vehicle. The hydrogen heat exchange tube 106 and the helium heat exchange tube 107 greatly increase the length and surface area of ​​the pipeline in a limited space, so that there is more contact time between hydrogen and helium, thereby improving the heat exchange efficiency and making the heat transfer more sufficient.

[0034] Optionally, the straight length of each folded-back section is 30 mm, 45 mm or 50 mm.

[0035] It should be noted that the surfaces of the hydrogen heat exchange tube 106 and the helium heat exchange tube 107 are also provided with regularly arranged hemispherical convex points, the height of which is 0.3 mm to 0.5 mm. Since the working pressure in the hydrogen heat exchange tube 106 is 0.3 MPa to 0.5 MPa higher than that in the helium heat exchange tube 107, the density of the convex points provided on the surface of the hydrogen heat exchange tube 106 should be 30% to 40% higher than that on the surface of the helium heat exchange tube 107.

[0036] By adding convex points, a stronger turbulence effect can be formed when hydrogen and helium flow in the tube, thereby improving the heat exchange efficiency. The convex point density of the hydrogen heat exchange tube 106 is large, because the hydrogen molecules move more violently under high pressure, and the dense convex points can achieve more efficient heat transfer.

[0037] It should be noted that the thermal conductivity of hydrogen and helium is relatively high among common gases. In the hydrogen-helium heat exchanger 1, the high thermal conductivity enables hydrogen and helium to quickly transfer heat, significantly improving the heat exchange efficiency. The two gases in the hydrogen heat exchange tube 106 and the helium heat exchange tube 107 circulate in their respective loops, continuously and efficiently exchanging heat, which significantly improves the heat exchange efficiency compared to traditional heat exchange methods and quickly reduces the temperature of the motor assembly 2.

[0038] A three-way solenoid valve 5 is arranged on the pipeline of the air conditioning heating component 3, and the three-way solenoid valve 5 includes a valve body, a valve core and a control unit (not shown in the figure). The valve core can quickly switch between different working modes under the precise control of the control unit. The heat dissipation component 4 is connected in parallel with the air conditioning heating component 3 through the three-way solenoid valve 5. When the three-way solenoid valve 5 is switched to a specific position, the hot fluid coming out of the hydrogen-helium heat exchanger 1 will flow to the heat dissipation component 4, and the heat will be dissipated to the external environment through the heat dissipation fins of the heat dissipation component 4; when the three-way solenoid valve 5 is switched to another position, the heat dissipation component 4 is disconnected from the system, and the hot fluid flows to the air conditioning heating component 3 to meet the needs of air conditioning heating. It not only reduces the waste of vehicle energy, but also improves the comprehensive utilization rate of energy, conforms to the development concept of energy conservation and environmental protection of new energy vehicles, and reduces the operating cost of vehicles.

[0039] In an embodiment of the present invention, the motor assembly 2 includes a power motor 201 and a first water pump 202; The first water pump 202 is arranged on the water outlet pipeline of the power motor 201 , the first water pump 202 is connected to the inlet end of the first heat exchange chamber 103 , and the outlet end of the first heat exchange chamber 103 is connected to the water inlet pipeline of the power motor 201 to form a loop.

[0040] The section of the hydrogen heat exchange tube 106 passing through the first heat exchange cavity 103 and the section of the helium heat exchange tube 107 passing through the second heat exchange cavity 104 are both spiral.

[0041] Specifically, the first water pump 202 is installed on the water outlet pipeline of the power motor 201 to promote the circulation of the fluid. One end of the first water pump 202 is connected to the water outlet pipeline of the power motor 201 to ensure that the fluid saturated with heat flowing out of the power motor 201 can smoothly enter the first water pump 202. The other end of the first water pump 202 is connected to the inlet end of the first heat exchange chamber 103, and the high-temperature fluid is continuously injected into the first heat exchange chamber 103 through the pumping capacity. The first heat exchange chamber 103 is used as a place for heat exchange and then returns the cooled fluid water to the power motor 201 for use.

[0042] like Figure 2 As shown, the portion of the hydrogen heat exchange tube 106 passing through the first heat exchange cavity 103 and the portion of the helium heat exchange tube 107 passing through the second heat exchange cavity 104 are both spiral. The space in the cavity is utilized, and the spiral shape greatly increases the contact area between the hydrogen heat exchange tube 106 and the fluid in the first heat exchange cavity 103, so that the heat in the fluid can be more fully transferred to the hydrogen in the hydrogen heat exchange tube 106. Similarly, the spiral portion of the helium heat exchange tube 107 in the second heat exchange cavity 104 also expands the contact range with the fluid in the cavity, so that the received waste heat is transferred to the fluid in the second heat exchange cavity 104.

[0043] In an embodiment of the present invention, the air conditioning heating component 3 includes a warm air water pump 301, a water heating PTC 302, and an air conditioning warm air core 303; the warm air water pump 301, the water heating PTC 302 and the air conditioning warm air core 303 are arranged in sequence along the water flow direction on the outlet end pipeline of the second heat exchange chamber 104; the outlet end of the air conditioning warm air core 303 is connected to the inlet end of the second heat exchange chamber 104 to form a loop; the three-way solenoid valve 5 is arranged in the upstream pipeline of the warm air water pump 301.

[0044] The heat dissipation component 4 includes a radiator 401, a fan 402, and a second water pump 403; one side of the inlet end of the radiator 401 is connected to the three-way solenoid valve 5, and one side of the outlet end of the radiator 401 is connected to the upstream pipeline of the second water pump 403; the air outlet of the fan 402 faces the radiator 401.

[0045] A plurality of temperature sensors 6 are also provided on the pipeline connecting the second heat exchange cavity 104 and the air conditioning heating component 3 .

[0046] The radiator 401 is a tubular radiator or an evaporative radiator.

[0047] Specifically, the air conditioning heating assembly 3 is used for heating in the car, and is composed of a warm air water pump 301, a water heating PTC 302, and an air conditioning warm air core 303. On the pipeline connected to the second heat exchange chamber 104, the components are arranged in sequence along the water flow direction. The warm air water pump 301 is located at the uppermost stream, and generates power through mechanical operation to promote the circulation flow, ensuring that the fluid heated by waste heat can enter the water heating PTC 302 continuously and stably. When the fluid heated once flows through the water heating PTC 302, the temperature is further increased and heated again. After being heated by the water heating PTC 302, it enters the air conditioning warm air core 303, and the heat is sent into the car inside the core. The outlet end of the air conditioning warm air core 303 is connected to the inlet end of the second heat exchange chamber 104 through a pipeline, forming a circulation loop. In this loop, the fluid whose heat is absorbed by the air conditioning warm air core 303 returns to the second heat exchange chamber 104 and is heated by helium. The three-way solenoid valve 5 is arranged in the upstream pipeline of the heater water pump 301, and can control the flow direction of the fluid according to actual needs. When heating is required in the vehicle, the three-way solenoid valve 5 directs the fluid to the air conditioning heating component 3 to participate in the heating cycle; when heating is not required, the three-way solenoid valve 5 changes the flow direction of the fluid to enter the heat dissipation component 4 for conventional heat dissipation.

[0048] The heat dissipation component 4 includes a radiator 401, a fan 402 and a second water pump 403. One side of the inlet end of the radiator 401 is connected to the three-way solenoid valve 5. The radiator 401 adopts different heat dissipation methods according to different types. If it is a tubular radiator, the fluid flows in the tube and transfers the heat to the surrounding air through the tube wall; if it is an evaporative radiator, the fluid evaporates inside the radiator, and a large amount of heat is taken away by the latent heat of evaporation to achieve efficient heat dissipation. The air outlet of the fan 402 faces the radiator 401 to accelerate the air flow. When the fan 402 is running, a large amount of air flows quickly through the surface of the radiator 401, taking away the heat emitted by the radiator 401 and dissipating it outside the vehicle. The second water pump 403 is located in the downstream pipeline on the outlet side of the radiator 401. Its function is similar to that of the warm air water pump 301, providing power for the fluid so that it can smoothly flow back to the second heating chamber to maintain circulation.

[0049] A plurality of temperature sensors 6 are also provided on the pipeline connecting the second heat exchange chamber 104 and the air conditioning heating assembly 3. These temperature sensors 6 are distributed at different positions to monitor the temperature change of the fluid in real time. They transmit the collected temperature data to the three-way solenoid valve 5 for control.

[0050] The embodiment of the present invention also provides a method for recovering waste heat from a new energy vehicle. The method uses the waste heat recovery device for a new energy vehicle in the above embodiment. Figure 3 As shown, the following steps are included: Step 1, the hot water flowing out of the motor assembly 2 flows through the first heat exchange chamber 103 to transfer the waste heat to the hydrogen in the hydrogen heat exchange pipe 106, and then cools down and flows back to the motor assembly 2; Specifically, the motor assembly 2 generates a large amount of heat during continuous operation, causing the temperature of the fluid in contact with it to rise sharply, forming high-temperature water. The hot water flows out of the power motor 201 along the pipeline, enters the first water pump 202 and flows into the first heat exchange chamber 103. Inside the first heat exchange chamber 103, the hydrogen heat exchange tube 106 is distributed in a spiral shape. When the hot water flows in the first heat exchange chamber 103, the waste heat it carries is transferred to the hydrogen in the hydrogen heat exchange tube 106. The hydrogen quickly absorbs heat, causing the temperature of the hot water to gradually decrease. After the heat exchange is completed, the cooled fluid flows back to the power motor 201 through the pipeline through the outlet end of the first heat exchange chamber 103, forming a continuous and stable cooling cycle. The operating temperature of the power motor 201 is controlled to ensure that it operates efficiently within an appropriate temperature range and avoid performance degradation and failures caused by overheating.

[0051] Step 2: The hydrogen in the hydrogen heat exchange tube 106 and the helium in the helium heat exchange tube 107 conduct heat transfer to exchange heat energy; the helium in the helium heat exchange tube 107 then flows through the cold water at the outlet end of the air conditioning heating component 3 to be heated; Specifically, after the hydrogen in the hydrogen heat exchange tube 106 absorbs the heat of the hot water, the temperature rises. At this time, the hydrogen and the helium in the adjacent helium heat exchange tube 107 conduct heat conduction through the tube wall. Because there is a temperature difference between the two gases, the heat is transferred from the high-temperature hydrogen to the low-temperature helium, realizing the exchange of heat energy between the two gases. After the heat exchange, the temperature of the helium increases significantly, carrying a large amount of heat energy. In the air conditioning heating component 3, there is heated cold water, and the cold water is at a relatively low temperature. The helium in the helium heat exchange tube 107 after the temperature rises contacts the cold water in the second heat exchange chamber 104, and transfers the heat it carries to the cold water. After the cold water absorbs the heat, it is ready for subsequent heating applications; it realizes the efficient transfer of heat from the waste heat of the motor component 2 to the cold water in the air conditioning heating component 3, and improves the utilization rate of energy.

[0052] Step 3, when the heated water flows through the three-way solenoid valve 5, the three-way solenoid valve 5 compares the heat Q1 generated by the motor component 2 and the heat Q2 required by the air-conditioning heating component 3, and then switches the flow rate to transport the waste heat to the air-conditioning heating component 3, completing the waste heat recovery of the new energy vehicle.

[0053] Specifically, Figure 4 As shown, the switching method of the flow switching of the three-way solenoid valve 5 is: there are four cases in total; The first one is that when the heat of Q1 is less than the heat of Q2 and the speed of the motor component 2 is greater than 0 (at this time the speed of the power motor 201 is not 0, indicating that it is working), the air conditioning heating component 3 heats itself by its own heat, closes the valve on one side of the air conditioning heating component 3, and opens one side of the heat dissipation component 4 to dissipate heat.

[0054] The second type is when the heat of Q1 is less than the heat of Q2 and the speed of motor component 2 is 0, it means that none of them are working and can be turned off.

[0055] The third method is to determine whether Q2 has excess heat according to the solenoid valve PID control method when the heat of Q1 is greater than or equal to the heat of Q2. When no heat is needed, the valve on one side of the heat dissipation component 4 is opened to dissipate heat; The fourth method is that when the heat of Q1 is greater than or equal to the heat of Q2, Q2 needs heat, closes the valve on one side of the heat dissipation component 4, opens and controls the opening of the valve on one side of the air-conditioning heating component 3, and uses the water after heat conduction to heat the air-conditioning heating component 3 to complete the waste heat recovery of the new energy vehicle.

[0056] It should be noted that the heat generated by the motor is Q1=CM(T1n-T1(n-1)), where T1n is the heat exchange temperature at the current moment, T1(n-1) is the heat exchange temperature at the previous moment, C is the specific heat capacity, and M is the mass; the heat required by the air conditioner is Q2=CM(target water temperature-T2), and T2 is the water temperature at the current moment.

[0057] like Figure 5 As shown, the solenoid valve PID control method uses the position PID and the incremental PID in parallel as the outer loop to calculate the target opening of the solenoid valve, and then connects the outer loop and the inner loop of the incremental PID in series to calculate the final opening of the solenoid valve; The calculation formula of the position PID of the outer loop is: (1); Among them, u(k) is the control output at the kth moment (the target opening of the solenoid valve); Kp is the proportional coefficient; e(k) is the error value at the kth moment (Q1-Q2); Ki is the integral coefficient; Ki×∑e(k) is the cumulative sum of all errors from the beginning to the kth moment, and Kd is the differential coefficient; The incremental PID calculation formula for the outer loop or inner loop is: (2); Among them, Δu(k) is the increment of the control quantity at the kth moment (the change in the target opening of the solenoid valve); Kp, Ki, Kd and e(k) are the same as those in the position PID; e(k-1) is the error value at the k-1th moment, and e(k-2) is the error value at the k-2th moment.

[0058] It should be noted that if Figure 5As shown, el(t) is Q1-Q2, ul(t) represents the target opening of the solenoid valve, e2(t) represents the target opening of the solenoid valve-the actual opening of the solenoid valve, and u2(t) represents the final output opening.

[0059] It should be noted that if the heat generated by the power motor 201 is not stable enough, the heat compensated to the air conditioning heating component 3 is also unstable. If the delivered heat is lower or higher than required, the temperature control will be unstable, affecting comfort. Therefore, in order to stably compensate the heat of the power motor 201 to the air conditioner, it is necessary to quickly respond to the change of heat during the heat climbing stage, predict the peak heat in advance, and accurately calculate after the heat reaches the peak and stabilizes. Through the analysis of the system, the position PID and the incremental PID are connected in parallel and then connected in series with the inner loop for calculation. When the heat exchange is unstable, the incremental PID is used to calculate the target opening of the solenoid valve. When the heat is stable, the position PID is used to calculate the target opening of the solenoid valve. The three-way solenoid valve 5 can be stably controlled, and the heat can be stably delivered to the air conditioning heating component 3.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A waste heat recovery device for new energy vehicles, characterized in that: include: A hydrogen-helium heat exchanger (1), a motor assembly (2), an air conditioning heating assembly (3), a heat dissipation assembly (4) and a three-way solenoid valve (5); The hydrogen-helium heat exchanger (1) comprises a shell (101), a partition (102), a first heat exchange cavity (103), a second heat exchange cavity (104), a tube sheet (105), a hydrogen heat exchange tube (106), and a helium heat exchange tube (107); The interior of the shell (101) is separated into the first heat exchange chamber (103) and the second heat exchange chamber (104) by two partitions (102), and the tube sheet (105) is arranged between the two partitions (102); the hydrogen heat exchange tube (106) passes through the first heat exchange chamber (103) and is led out from the tube sheet (105) to form a loop; the helium heat exchange tube (107) is introduced from the tube sheet (105) and passes through the second heat exchange chamber (104) to form a loop, the hydrogen heat exchange tube (106) and the helium heat exchange tube (107) are staggered, and the straight length of the hydrogen heat exchange tube (106) and the helium heat exchange tube (107) on the tube sheet (105) is 30 mm to 50 mm; The first heat exchange chamber (103) is connected to the motor assembly (2), and the second heat exchange chamber (104) is connected to the air conditioning heating assembly (3). A three-way solenoid valve (5) is also provided on the pipeline of the air conditioning heating assembly (3), and the heat dissipation assembly (4) is connected in parallel with the air conditioning heating assembly (3) via the three-way solenoid valve (5).

2. The waste heat recovery device for new energy vehicles according to claim 1, characterized in that: The section of the hydrogen heat exchange tube (106) passing through the first heat exchange cavity (103) and the section of the helium heat exchange tube (107) passing through the second heat exchange cavity (104) are both spiral.

3. The waste heat recovery device for new energy vehicles according to claim 1, characterized in that: The motor assembly (2) comprises a power motor (201) and a first water pump (202); The first water pump (202) is arranged on the water outlet pipeline of the power motor (201), the first water pump (202) is connected to the inlet end of the first heat exchange chamber (103), and the outlet end of the first heat exchange chamber (103) is connected to the water inlet pipeline of the power motor (201) to form a loop.

4. The waste heat recovery device for new energy vehicles according to claim 1, characterized in that: The air conditioning heating component (3) comprises a warm air water pump (301), a water heating PTC (302), and an air conditioning warm air core (303); The warm air water pump (301), the water heating PTC (302) and the air conditioning warm air core (303) are arranged in sequence along the water flow direction on the outlet pipeline of the second heat exchange chamber (104); the outlet end of the air conditioning warm air core (303) is connected to the inlet end of the second heat exchange chamber (104) to form a loop; the three-way solenoid valve (5) is arranged in the upstream pipeline of the warm air water pump (301).

5. The waste heat recovery device for new energy vehicles according to claim 1, characterized in that: The heat dissipation component (4) comprises a radiator (401), a fan (402), and a second water pump (403); One side of the inlet end of the radiator (401) is connected to the three-way solenoid valve (5), and one side of the outlet end of the radiator (401) is connected to the upstream pipeline of the second water pump (403); the air outlet of the fan (402) faces the radiator (401).

6. The waste heat recovery device for new energy vehicles according to claim 4 is characterized in that: A plurality of temperature sensors (6) are also provided on the pipeline connecting the second heat exchange chamber (104) and the air conditioning heating component (3).

7. The waste heat recovery device for new energy vehicles according to claim 5, characterized in that: The radiator (401) is a tubular radiator or an evaporative radiator.

8. A method for recovering waste heat from new energy vehicles, characterized in that: The method uses the new energy vehicle waste heat recovery device according to any one of claims 1 to 7, comprising the following steps: Step 1, the hot water flowing out of the motor assembly (2) flows through the first heat exchange chamber (103) to transfer waste heat to the hydrogen in the hydrogen heat exchange pipe (106), and then cools down and flows back to the motor assembly (2); Step 2, the hydrogen in the hydrogen heat exchange tube (106) and the helium in the helium heat exchange tube (107) conduct heat to exchange heat energy; the helium in the helium heat exchange tube (107) then flows through the cold water at the outlet end of the air conditioning heating component (3) to be heated; Step 3: When the heated water flows through the three-way solenoid valve (5), the three-way solenoid valve (5) compares the heat Q1 generated by the motor component (2) with the heat Q2 required by the air-conditioning heating component (3), and then switches the flow direction of the three-way solenoid valve (5) to transport the waste heat to the air-conditioning heating component (3), thereby completing the waste heat recovery of the new energy vehicle.

9. The method for recovering waste heat from new energy vehicles according to claim 8, characterized in that: The switching method of the flow direction of the three-way solenoid valve (5) in step 3 is: When the heat of Q1 is less than the heat of Q2 and the rotation speed of the motor component (2) is greater than 0, the air conditioning heating component (3) is heated by its own heat, the valve on one side of the air conditioning heating component (3) is closed, and the heat dissipation component (4) is opened to dissipate heat; When the heat of Q1 is greater than or equal to the heat of Q2, it is determined whether Q2 has excess heat according to the solenoid valve PID control method, and when heat is not needed, the valve on one side of the heat dissipation component (4) is opened; When heat is needed, the valve on one side of the heat dissipation component (4) is closed, and the valve on one side of the air conditioning heating component (3) is opened and the opening is controlled, and the air conditioning heating component (3) is heated by water after heat conduction, thereby completing the waste heat recovery of the new energy vehicle.

10. The method for recovering waste heat from new energy vehicles according to claim 9, characterized in that: The solenoid valve PID control method adopts position PID and incremental PID in parallel as an outer loop to calculate the target opening of the solenoid valve, and then connects the outer loop and the inner loop incremental PID in series to calculate the final opening of the solenoid valve; The position PID calculation formula in the outer loop is: （1）； Among them, u(k) is the control output at the kth moment; Kp is the proportional coefficient; e(k) is the error value (Q1-Q2) at the kth moment; Ki is the integral coefficient; Ki×∑e(k) is the cumulative sum of all errors from the beginning to the kth moment, and Kd is the differential coefficient; The incremental PID calculation formula in the outer loop or inner loop is: （2）； Among them, Δu(k) is the increment of the control quantity at the kth moment; Kp, Ki, Kd and e(k) are the same as those in the position PID; e(k-1) is the error value at the k-1th moment, and e(k-2) is the error value at the k-2th moment.

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