Sharing compressor energy storage type semiconductor vehicle-mounted refrigerator and control method thereof

Abstract

The invention provides a shared compressor energy storage type semiconductor vehicle-mounted refrigerator and a control method thereof, and solves the problems of heat management and the like of a vehicle-mounted refrigerator, the shared compressor energy storage type semiconductor vehicle-mounted refrigerator comprises a thermoelectric semiconductor module used for refrigerating or heating the interior of the refrigerator; the cold storage module is used for storing and releasing cold energy; one face of the cold plate heat exchanger is in heat conduction connection with the hot end of the thermoelectric semiconductor module, a refrigerant flow channel is formed in the cold plate heat exchanger, and the refrigerant flow channel is sequentially connected with a refrigerator expansion valve and a one-way valve through a pipeline, then is connected into a whole vehicle heat management system, is connected with an automobile air conditioner refrigerating loop and a battery cooling loop in parallel and shares a whole vehicle compressor and a condenser; the one-way valve prevents high-pressure refrigerants of the air conditioner or the battery cooling loop from flowing back into the refrigerator loop when the refrigerator does not work. The system has the advantages of stable operation, good heat management effect and the like.

Description

Technical Field

[0001] This invention belongs to the field of vehicle-mounted refrigerator technology, specifically relating to a shared compressor energy storage semiconductor vehicle-mounted refrigerator and its control method. Background Technology

[0002] In recent years, with the growing popularity of the "car-home" concept, car refrigerators have become a standard feature in more and more vehicles, offering greater convenience to travelers. Traditional car refrigerator technologies mainly include independent compressor type and semiconductor type. Independent compressor car refrigerators use traditional compressor refrigeration technology, achieving low cooling temperatures (down to -18℃) and high cooling efficiency, but are expensive, noisy, heavy, and have low effective volume ratio. Semiconductor car refrigerators utilize the Peltier effect of thermoelectric semiconductors, enabling both cooling and heating. They offer advantages such as low cost, small size, and no chemical pollution, but suffer from drawbacks such as low cooling efficiency, cooling temperature affected by ambient temperature, and difficulty in reaching sub-zero temperatures.

[0003] Another vehicle-mounted refrigerator technology involves connecting the refrigerator's evaporator in parallel to the vehicle's compressor refrigeration system to achieve the refrigerator's cooling function. Chinese patent publication number CN218929297U proposes a vehicle-mounted refrigerator with cold storage function, which uses a cold storage module to insulate the refrigerator and avoid frequent compressor starts and stops during operation. However, a significant drawback of this solution is that the refrigerator's cooling temperature is limited by the refrigerant temperature of the vehicle's compressor refrigeration system, which is typically above 0°C. A recent novel vehicle-mounted refrigerator technology involves connecting a semiconductor refrigerator to the vehicle's compressor refrigeration system. The compressor's refrigerant is used to dissipate heat from the semiconductor's hot end, while the cold end cools the refrigerator's interior. The internal cooling temperature can reach below -20°C, independent of the refrigerant temperature of the vehicle's compressor refrigeration system. Simultaneously, a cold storage module can be added to the refrigerator to store cold energy, maintain the internal temperature, and prevent frequent compressor starts and stops.

[0004] However, the coupling of the vehicle-mounted refrigerator with the vehicle's thermal management system greatly increases the complexity of the entire system control, requiring the development of a reasonable system control strategy to avoid affecting the performance and reliability of both the vehicle's thermal management system and the refrigerator. Therefore, this invention provides a shared compressor energy storage semiconductor vehicle-mounted refrigerator integrated with the vehicle's thermal management system and its control method. Summary of the Invention

[0005] The purpose of this invention is to address the above-mentioned problems by providing a reasonably designed and stable shared compressor energy storage semiconductor vehicle-mounted refrigerator.

[0006] Another objective of this invention is to address the aforementioned problems by providing a control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator with good thermal management performance.

[0007] To achieve the above objectives, the present invention adopts the following technical solution: a shared compressor energy storage semiconductor vehicle refrigerator, comprising: Thermoelectric semiconductor modules are used to cool or heat the interior of a refrigerator. A cold storage module is used to store and release cold energy. The cold plate heat exchanger has one side thermally connected to the hot end of the thermoelectric semiconductor module. Internally, it has a refrigerant flow channel. This channel is connected via pipes to a refrigerator expansion valve and a one-way valve, before entering the vehicle's thermal management system. It operates in parallel with the vehicle's air conditioning and battery cooling circuits, sharing the vehicle's compressor and condenser. The one-way valve prevents high-pressure refrigerant from the air conditioning or battery cooling circuits from flowing back into the refrigerator circuit when the refrigerator is not operating. As a heat exchange hub, the cold plate heat exchanger transfers waste heat generated by the thermoelectric semiconductor to the flowing refrigerant and, conversely, transfers the refrigerant's cooling capacity to the cold storage module, achieving heat flow coupling and distribution.

[0008] The cold storage module includes a sealed cavity filled with phase change material (PCM). The other side of the cold plate heat exchanger is thermally connected to the cold storage module, allowing the refrigerant flowing through the refrigerant channel to simultaneously dissipate heat from the hot end of the thermoelectric semiconductor module and charge the cold storage module. The core of the cold storage module is the latent heat of phase change of the PCM. When the cold plate temperature is lower than the PCM's phase change temperature, the PCM solidifies, releasing a large amount of latent heat, which is carried away by the refrigerant, achieving charging. When the cold plate temperature rises due to the shutdown of the vehicle's compressor, the PCM melts, absorbing the same large amount of latent heat, providing cooling to the cold plate, achieving releasing.

[0009] In the aforementioned shared compressor energy storage semiconductor vehicle-mounted refrigerator, the refrigerator expansion valve is an electromagnetic thermostatic expansion valve with a diameter of no more than 1 mm. This valve integrates a solenoid valve for switching on and off the refrigerant pipeline and a thermostatic expansion valve for automatically adjusting the refrigerant superheat. The ultra-small diameter ensures that the refrigerant flow through the refrigerator circuit matches the refrigerator's minimal heat dissipation, preventing overflow from causing uncontrolled evaporation temperature. The solenoid valve is responsible for quickly opening and closing the pipeline according to control commands; the thermostatic expansion valve senses the outlet superheat through its temperature sensing bulb and mechanically and automatically adjusts its opening to ensure evaporator utilization and prevent liquid slugging in the vehicle compressor. Together, they ensure stable and reliable operation under low flow conditions.

[0010] In the aforementioned shared compressor energy storage semiconductor vehicle refrigerator, the thermoelectric semiconductor module includes a thermoelectric semiconductor chip, a cold end heat sink attached to its cold end, and an internal circulation fan that causes air inside the refrigerator to flow through the cold end heat sink.

[0011] In the aforementioned shared compressor energy storage semiconductor vehicle refrigerator, the phase change material is an organic phase change material with a phase change temperature (Tb) ranging from -10℃ to 0℃. This temperature range was chosen primarily for two reasons: first, its phase change temperature is lower than the commonly used insulation temperature of refrigerators, ensuring effective maintenance of the low temperature inside the refrigerator during cooling; second, it exhibits low corrosivity and good phase change stability, making it suitable for long-term use in vehicle environments. This temperature range also represents a balance between refrigeration performance and system energy consumption.

[0012] A control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator includes the following modes: Cooling mode: Open the refrigerator expansion valve, request the start of the vehicle compressor, start the thermoelectric semiconductor module cooling and internal circulation fan to cool the inside of the box and charge the cold storage module at the same time; when the temperature inside the box T refrigerator reaches the set temperature Tset, and the temperature of the cold storage module T cold storage is lower than its phase change temperature Tb - first offset △T0, switch to heat preservation mode; stopping the machine only when the box temperature reaches the standard will cause the vehicle compressor to start and stop frequently; it is necessary to wait for the core of the cold storage module to also complete the phase change, that is, T cold storage ≤ Tb - △T0, which means that the maximum available latent heat has been stored to ensure the heat preservation for a long time. The setting of △T0 ensures the full completion of the phase change process.

[0013] In insulation mode: The system requests the shutdown of the vehicle compressor and delays the closure of the refrigerator expansion valve. The thermoelectric semiconductor module and internal circulation fan adjust according to the internal temperature, and the cold storage module releases cold. When the temperature of the cold storage module, Tcold storage, is higher than its phase change temperature, Tb - the second offset, ΔT1, the system switches back to cooling mode. The delayed closure of the refrigerator expansion valve allows residual refrigerant in the pipeline to flow back, protecting the vehicle compressor. In insulation mode, the TEC and internal circulation fan still operate under controlled conditions, but the required cooling capacity mainly comes from the release of the latent heat of phase change from the cold storage module, allowing the vehicle compressor to rest for an extended period. When Tcold storage ≥ Tb + ΔT1, it indicates that the phase change material has completely melted, and the sensible heat reserve is limited. The vehicle compressor needs to be restarted for cooling and charging, thus forming a complete energy storage-release cycle.

[0014] Heating mode: The thermoelectric semiconductor module and the internal circulation fan are activated to heat the inside of the box.

[0015] Standby mode: Turns off the thermoelectric semiconductor module and internal circulation fan, and closes the refrigerator expansion valve after a delay after requesting to shut down the vehicle compressor.

[0016] In the aforementioned control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator, the values ​​of the first offset ΔT0 and the second offset ΔT1 range from 3℃ to 10℃. This is taken into account measurement accuracy, the material phase transition temperature range, and control stability. An excessively small ΔT value may cause frequent mode switching near the phase transition point; an excessively large ΔT value reduces the effective utilization rate of the cold storage capacity. An offset of 3-10℃ provides the system with a clear mode switching hysteresis, ensuring stable operation.

[0017] In the aforementioned control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator, in both cooling and insulation modes, a PID control algorithm generates control signals to adjust the input power of the thermoelectric semiconductor module and the speed of the internal circulation fan, respectively, so that the internal temperature approaches and is maintained at the set temperature. The PID algorithm uses the deviation between the internal temperature and the set value as input, and its output can be used as the target control variable. For the TEC, the cooling / heating power is typically linearly adjusted by changing its drive voltage or current. For the fan, the PWM duty cycle is adjusted to change the speed, thereby adjusting the convective heat transfer intensity between the air inside the refrigerator and the cold-end radiator. Both can be adjusted independently or in tandem to achieve a balance between rapid cooling and precise temperature control.

[0018] In the above-mentioned control method of a shared compressor energy storage semiconductor vehicle refrigerator, when the refrigerator is running independently, the vehicle compressor runs in low power mode, and the temperature of the refrigerant flowing through the cold plate heat exchanger is lower than the phase change temperature Tb, which can charge the cold storage module. When the refrigerator operates in conjunction with the air conditioner or battery cooling system, the refrigerant temperature flowing through the cold plate heat exchanger is higher than the phase change temperature Tb, making it unable to charge the cold storage module. When operating independently, the vehicle compressor has a low load, and the system can adjust to operate at a low evaporation pressure, thereby achieving a lower refrigerant temperature to meet the charging requirements. During joint operation, the vehicle compressor's evaporation pressure primarily meets the cooling needs of the air conditioner or battery. At this time, the refrigerant temperature in the refrigerator circuit is higher, mainly used for TEC heat dissipation, and the charging function is automatically suspended. The control strategy can recognize this difference.

[0019] The control method for the shared compressor energy storage semiconductor vehicle-mounted refrigerator described above also includes fault modes: When a system fault is detected, shut down the thermoelectric semiconductor module and the internal circulation fan; If the source of the fault is not the vehicle compressor, the refrigerator expansion valve will be closed after a delay following the request to shut down the vehicle compressor. If the fault is caused by the vehicle compressor, keep the refrigerator expansion valve open.

[0020] In the aforementioned control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator, in the refrigerator's independent cooling mode, if the vehicle compressor fails to start within a preset time after a request to start it, or fails to shut down within a preset time after a request to shut down it in the insulation mode, the vehicle compressor is deemed to be faulty, and the system enters a fault mode. Since the vehicle compressor is centrally managed by the vehicle controller, and the refrigerator controller controls it via communication requests, a timeout judgment mechanism is required. The preset time is used to distinguish between normal response delays and faults, ensuring that the system can promptly detect abnormalities in the vehicle compressor's operation and transition to a safe state.

[0021] Compared with existing technologies, the advantages of this invention are: 1. The low-temperature refrigerant of the vehicle's air conditioning system is directly used to actively and efficiently dissipate heat from the hot end of the thermoelectric semiconductor (TEC), which greatly reduces the temperature of the TEC hot end and thus significantly improves its cooling efficiency and temperature difference capability. 2. The cooling capacity inside the refrigerator is directly generated by the cold end of the TEC, and is not directly limited by the temperature of the refrigerant in the whole vehicle. The refrigerant in the whole vehicle is only used to dissipate heat from the hot end of the TEC, thereby decoupling the cooling depth of the refrigerator from the operating conditions of the whole vehicle's air conditioning, and realizing deep cooling under the shared system. 3. When the vehicle compressor is stopped or the refrigerator is running in conjunction with it, the cold storage module releases cold to provide cooling for the refrigerator body and the TEC hot end, thereby significantly extending the downtime of the vehicle compressor and reducing its start-stop frequency. 4. It shares the existing compressor, condenser and other components of the vehicle. Only the TEC module, cold storage module and small expansion valve need to be added to the refrigerator side, which greatly reduces the hardware cost, weight and installation space of the vehicle refrigerator. 5. The system can identify different operating scenarios and adjust the control logic to ensure the reliable implementation of the refrigerator function under various operating conditions, and avoid adverse interference to the vehicle's air conditioning or battery cooling system. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the refrigerator structure of the present invention; Figure 2 This is a diagram of the phase change cooling process of the cold storage material of the present invention; Figure 3 This is a diagram illustrating the phase change and heat release process of the cold storage material of the present invention; Figure 4 This is a flowchart of the mode switching process of the present invention; Figure 5 This is a flowchart of the control method of the present invention; Figure 6 This is a schematic diagram of the phase change temperature of the phase change energy storage material of the present invention; Figure 7This is the control logic diagram of the PID temperature control regulating TEC power and the internal circulation fan of the present invention; Figure 8 This is a schematic diagram of the target temperature difference-fan PWM comparison of the present invention; Figure 9 This is a comparison chart of the target temperature difference and the rate of change of the target temperature according to the present invention; In the diagram, there are thermoelectric semiconductor module 1, cold storage module 2, cold plate heat exchanger 3, refrigerator expansion valve 31, one-way valve 32, automotive air conditioning refrigeration circuit 4, vehicle compressor 41, condenser 42, and battery cooling circuit 5. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0024] like Figure 1-9 As shown, a shared compressor energy storage semiconductor vehicle refrigerator specifically includes: a thermoelectric semiconductor module 1, which serves as the refrigerator's heat source and is used to directly cool or heat the air inside the refrigerator; a cold storage module 2, which is filled with phase change material to store and release cold energy in the form of latent heat at high density; a cold plate heat exchanger 3, which serves as a key thermal coupling and exchange component, with one side thermally connected to the hot end of the thermoelectric semiconductor module 1 to remove its waste heat, and the other side thermally connected to the cold storage module 2, and has a refrigerant flow channel inside; and a parallel-connected vehicle thermal management system, where the refrigerant flow channel of the cold plate heat exchanger 3 is connected to a dedicated refrigerator expansion valve 31 and a one-way valve 32 via pipes, and then connected to the vehicle refrigerant circuit, forming a parallel relationship with the vehicle air conditioning cooling circuit 4 and the battery cooling circuit 5, thereby sharing the vehicle compressor 41 and condenser 42.

[0025] The control method of the vehicle refrigerator is based on a state machine that includes multiple working modes. The switching between the cooling mode and the heat preservation mode is based on the temperature inside the refrigerator reaching the set value and the phase change state of the cold storage module reaching a specific threshold, such as T cold storage ≤ Tb-△T0 and T cold storage ≥ Tb+△T1 as key criteria. This enables optimized management of the start and stop of the vehicle compressor 41 and efficient storage and utilization of cold energy. Example 1

[0026] This embodiment provides a basic architecture for a shared compressor energy storage semiconductor vehicle-mounted refrigerator. The system mainly includes a thermoelectric semiconductor module 1, a cold storage module 2, and a cold plate heat exchanger 3. The thermoelectric semiconductor module 1 is installed inside the refrigerator body or in the air duct, and its cold end is used to directly or indirectly cool the air inside the refrigerator.

[0027] The cold storage module 2 is an independent container encapsulated with phase change material. The cold plate heat exchanger 3 is a key coupling component. One side of its plane is tightly attached to the hot end of the thermoelectric semiconductor module 1 by means of thermal grease or soldering to dissipate the waste heat generated therefrom; the other side of its plane is in close contact with the outer wall or internal thermal conductive structure of the cold storage module 2.

[0028] The cold plate heat exchanger 3 has a meandering refrigerant flow channel inside. The inlet of this channel is connected to a dedicated refrigerator expansion valve 31 via a pipeline, and the outlet is connected to a one-way valve 32 via a pipeline. The outlet of the one-way valve 32 is connected to the vehicle's low-pressure refrigerant pipeline, thereby forming a parallel relationship between the refrigerator circuit, the vehicle's air conditioning cooling circuit 4, and the battery cooling circuit 5, which share the vehicle's compressor 41 and condenser 42.

[0029] In this architecture, the high-pressure liquid refrigerant flowing from the condenser 42 is throttled by the refrigerator expansion valve 31, becoming a low-temperature, low-pressure vapor-liquid mixture that flows into the cold plate heat exchanger 3. The refrigerant evaporates and absorbs heat within the flow channel, simultaneously performing two tasks: first, cooling the hot end of the thermoelectric semiconductor module 1, which is in contact with the heat exchanger, thereby improving its cooling efficiency; and second, cooling the cold storage module 2, which is in contact with it, causing the phase change material inside to solidify and store cold. Example 2

[0030] This embodiment specifically defines the refrigerator expansion valve 31. The refrigerator expansion valve 31 is a one-piece molded electromagnetic thermostatic expansion valve with a valve body diameter of 0.8mm. The valve integrates two functional units: The solenoid valve unit is controlled by a switching signal sent by the refrigerator controller, and can instantly open or completely cut off the refrigerant flowing to the refrigerator circuit. The thermostatic expansion valve unit has its temperature sensing bulb tightly fixed to the refrigerant outlet pipe of the cold plate heat exchanger 3. By sensing the refrigerant temperature and pressure at that location, it drives the mechanical mechanism inside the valve to automatically adjust the throttling opening.

[0031] This integrated design allows the refrigerator expansion valve 31 to function as both a controlled on / off valve and a self-regulating expansion mechanism, making it particularly suitable for vehicle refrigerators with low and fluctuating heat loads. The design with a diameter of no more than 1mm ensures precise flow matching, preventing excessively high evaporation temperatures due to excessive flow or uncontrolled overheating of the vehicle compressor 41 due to insufficient flow. Example 3

[0032] In this embodiment, the thermoelectric semiconductor module 1 is assembled from the following components stacked from top to bottom: The cold-end heat sink uses an aluminum finned heat sink, which is bonded to the cold side of the thermoelectric semiconductor chip via a thermally conductive substrate. The thermoelectric semiconductor chip is a standard Peltier device consisting of multiple pairs of PN junctions connected in series. The hot-end thermally conductive substrate is a flat copper plate that evenly conducts heat from the hot side of the thermoelectric semiconductor chip to the cold plate heat exchanger 3. The internal circulation fan is a DC brushless fan, installed inside the refrigerator compartment, driving the air inside the compartment to flow through the gaps between the fins of the cold-end heat sink for convective heat transfer.

[0033] With this structure, the cold energy generated by the thermoelectric semiconductor chip is efficiently absorbed by the cold end heat sink and carried throughout the entire chamber by the airflow driven by the internal circulation fan. Example 4

[0034] This embodiment provides specific definitions and preferred descriptions of phase change materials. Phase change energy storage materials utilize the latent heat of solid-liquid phase change to store the cooling capacity of the refrigeration system where the vehicle compressor 41 is located, for heat dissipation of the semiconductor refrigeration module in refrigerator insulation mode.

[0035] like Figure 6 As shown, the selection criteria for low-temperature organic phase change materials are as follows: First, the phase change temperature Tb of the low-temperature organic phase change material must be higher than the refrigerant temperature Tr to meet the requirements of phase change energy storage, i.e., Tb>Tr. For the low-pressure circuit of the refrigerator refrigerant in the shared vehicle compressor 41, the refrigerant temperature is as low as -20℃. Considering the large thermal resistance of the heat exchanger between the refrigerant and the organic phase change material (approximately 0.1K / W or more), the low thermal conductivity of the organic phase change material (<1W / m·K), and the non-uniformity of the phase change (the values ​​of the first offset ΔT0 and the second offset ΔT1 range from 3℃ to 10℃), it is recommended that the phase change temperature be more than 10℃ higher than the refrigerant temperature, i.e., Tb-Tr≥10℃. Second, the lower the phase change temperature Tb of the phase change energy storage material, the lower the heat dissipation end temperature Th of the semiconductor refrigeration module, the lower its cold end temperature Tc, and the lower the refrigerator temperature Tf can also be achieved.

[0036] Therefore, low-temperature organic phase change materials are selected from alkanes, alcohols, and their aqueous solutions with phase change temperatures of -10℃ to 0℃ and high latent heat of phase change. Several typical low-temperature organic phase change materials include: n-dodecane, with a solid-liquid phase change temperature of approximately -10℃; and n-tetradecane, with a solid-liquid phase change temperature of 0-3℃. Selecting organic phase change materials within this temperature range not only meets thermodynamic matching requirements but also, due to their low corrosivity and good phase change stability, makes them suitable for long-term use in automotive environments. Example 5

[0037] In this embodiment, the basic control method for the vehicle-mounted refrigerator includes five main modes: cooling, heat preservation, heating, standby, and fault. The switching logic is as follows: Standby mode: The initial state of the system upon power-up. If a cooling command is received, it enters cooling mode; if a heating command is received, it enters heating mode.

[0038] Cooling mode: The controller performs the following actions: opens the refrigerator expansion valve 31; sends a request to the vehicle controller to start the vehicle compressor 41; and starts the thermoelectric semiconductor module 1 cooling and internal circulation fan. The system continuously monitors the internal temperature Trefrigerator and the temperature of the cold storage material Tcold storage.

[0039] Insulation mode: When both conditions T_refrigerator ≤ T_set and T_cold storage ≤ T_b - ΔT_0 are met simultaneously, the system switches from cooling mode to this mode. Controller execution: A request is sent to the vehicle controller to shut down the vehicle compressor 41; after the vehicle compressor 41 is confirmed to be shut down, the refrigerator expansion valve 31 is closed after a 2-second delay; the thermoelectric semiconductor module 1 and the internal circulation fan switch to low-power operation.

[0040] Heating mode: Upon receiving a heating command, the thermoelectric semiconductor module 1 is directly activated for heating and the internal circulation fan is activated, without involving the control of the vehicle compressor 41 and the refrigerator expansion valve 31.

[0041] Fault mode: If a fault is detected in any mode, such as abnormal temperature sensor or communication timeout, immediately shut down thermoelectric semiconductor module 1 and internal circulation fan, and handle refrigerator expansion valve 31 and vehicle compressor 41 according to the predetermined strategy based on the fault type. Example 6

[0042] In this embodiment, the first offset △T0, the offset for the completion of cold storage, is set to 8°C, and the second offset △T1, the offset for the end of cold release, is set to 7°C.

[0043] When the temperature of the cold storage material, T, drops to Tb-8℃, the system considers that the cold storage module 2 has fully completed phase change solidification and stored the maximum usable latent heat, and can switch to the heat preservation mode. In the heat preservation mode, when the temperature of the cold storage material rises back to Tb+7℃ due to continuous cooling, the system considers that its latent heat of phase change has been basically released, and it needs to switch back to the cooling mode to recharge.

[0044] Setting an offset range of 3℃ to 10℃ creates a clear control hysteresis loop, effectively avoiding frequent mode oscillations caused by minor fluctuations in temperature measurement or uneven local phase transformation of materials. Example 7

[0045] This embodiment provides a specific control method for adjusting the TEC power and the internal circulation fan using PID temperature control.

[0046] In both cooling and insulation modes, the controller uses the setpoint Tset of the internal temperature as the target and the measured internal temperature T_refrigerator as feedback, running a digital PID control algorithm. Its control logic is as follows: The temperature difference ∆T between the refrigerator's target temperature Tset and its current temperature T is used as the control parameter for adjusting the PWM of the internal circulation fan. The fan PWM is positively correlated with the refrigerator temperature difference ∆T. After calculating the PWM parameters of the circulation fan, the fan power is output to control its output.

[0047] Simultaneously, the target temperature change rate, Targe_VT, is calculated using the temperature difference ∆T between the refrigerator's target temperature, Tset, and its current temperature, T. The target temperature change rate is positively correlated with the temperature difference ∆T. The current temperature change rate, VT, is then calculated using the refrigerator's current temperature. Both the target temperature change rate, Targe_VT, and the current temperature change rate, VT, are used as inputs to the PID calculation module. After proportional-integral-derivative (PI) operations, the TEC's required power is obtained, and the actual output power of the TEC is then set.

[0048] The output of the PID algorithm is mapped to the duty cycle of a pulse width modulation (PWM) signal. For the TEC (Thermoelectric Temperature Coefficient), this PWM signal drives its power supply circuit; an increase in the duty cycle leads to a higher average voltage applied to the thermoelectric semiconductor, resulting in increased cooling / heating power. For the internal circulation fan, the output of the PID algorithm is independently calculated and converted into the duty cycle of another PWM signal to control the fan speed; a higher speed enhances heat exchange and results in more uniform temperature within the chamber.

[0049] Through real-time calculations using the aforementioned PID algorithm, the system can dynamically coordinate cooling capacity (TEC power) and cooling capacity (fan speed) to achieve rapid cooling and precise temperature control. Example 8

[0050] In this embodiment, when neither the air conditioner nor the battery cooling is activated, the refrigerator is the sole load on the vehicle compressor 41. At this time, the controller can request the vehicle compressor 41 to operate at its lowest speed, generating a lower evaporation pressure, so that the temperature of the refrigerant flowing through the cold plate heat exchanger 3 can reach about -15°C, which is far below the phase change temperature Tb, thereby efficiently charging the cold storage module 2.

[0051] When the driver turns on the air conditioning, the vehicle compressor 41 will primarily meet the temperature requirements of the air conditioning evaporator. At this time, even if the refrigerator is also working, the temperature of the refrigerant flowing through the refrigerator circuit will be raised to above 0°C by the overall system pressure, which is higher than Tb. Therefore, the cold storage module 2 cannot charge for cooling during this stage, but the refrigerant can still effectively dissipate heat from the TEC hot end, ensuring the basic cooling function of the refrigerator. Example 9

[0052] This embodiment mainly implements fault handling for graded safety protection. The fault modes defined in the control method have different processing logics based on different fault sources: Level 1 faults are non-compressor faults, such as overcurrent in thermoelectric semiconductor module 1, stalled internal circulation fan, or malfunction of the internal temperature sensor. The procedure is to immediately shut down thermoelectric semiconductor module 1 and the internal circulation fan; request the shutdown of the vehicle compressor 41; and after receiving a confirmation signal that the vehicle compressor 41 has been shut down, delay the shutdown of the refrigerator expansion valve 31.

[0053] Level 2 faults are compressor-related faults, such as communication interruption with the vehicle controller, or compressor response timeout as determined by the logic in Example 10. The procedure is to immediately shut down thermoelectric semiconductor module 1 and the internal circulation fan; however, the refrigerator expansion valve 31 remains open. This is to prevent the refrigerator circuit from becoming a completely closed container, where residual refrigerant may generate dangerous high pressure due to thermal expansion and contraction when the ambient temperature changes. Keeping the valve open allows the pipeline pressure to balance with the low-pressure side of the vehicle, ensuring safety. Example 10

[0054] This embodiment provides a monitoring method for a shared compressor. Since the vehicle compressor 41 is managed centrally by the vehicle controller, the refrigerator controller sends request commands via the bus. To monitor its execution status, a timeout judgment mechanism is added. In the refrigerator's independent cooling mode, the controller starts a 5-second timer after sending a compressor start request. If no feedback signal indicating that the compressor is running is received via the bus within 5 seconds, it is determined that the compressor start-up has failed.

[0055] In keep-warm mode, after sending a compressor shutdown request, the controller also starts a 5-second timer. If no feedback signal indicating compressor shutdown is received within 5 seconds, it is determined to be a compressor shutdown failure.

[0056] Once any of the above compressor faults is determined, the controller immediately and unconditionally enters fault mode and executes the second-level fault handling strategy in Example 9 to ensure system safety.

[0057] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

[0058] Although this document frequently uses terms such as thermoelectric semiconductor module 1, cold storage module 2, cold plate heat exchanger 3, refrigerator expansion valve 31, one-way valve 32, automotive air conditioning refrigeration circuit 4, vehicle compressor 41, condenser 42, and battery cooling circuit 5, the possibility of using other terms is not excluded. The use of these terms is merely for the convenience of describing and explaining the essence of this invention; interpreting them as any additional limitation would contradict the spirit of this invention.

Claims

1. A shared compressor energy storage semiconductor vehicle-mounted refrigerator, characterized in that, include: Thermoelectric semiconductor module (1) is used to cool or heat the refrigerator compartment; The cold storage module (2) is used to store and release cold energy; The cold plate heat exchanger (3) has one side thermally connected to the hot end of the thermoelectric semiconductor module (1). It has a refrigerant flow channel inside. The refrigerant flow channel is connected to a refrigerator expansion valve (31) and a one-way valve (32) in sequence through a pipe, and then connected to the vehicle thermal management system. It is connected in parallel with the car air conditioning refrigeration circuit (4) and the battery cooling circuit (5), and shares the vehicle compressor (41) and condenser (42). The cold storage module (2) includes a sealed cavity filled with phase change material. The other side of the cold plate heat exchanger (3) is thermally connected to the cold storage module (2), so that the cold medium flowing through the cold medium channel can simultaneously dissipate heat from the hot end of the thermoelectric semiconductor module (1) and charge the cold storage module (2). The phase change material is an organic phase change material, and its phase change temperature Tb ranges from -10℃ to 0℃.

2. The shared compressor energy storage semiconductor vehicle-mounted refrigerator according to claim 1, characterized in that, The refrigerator expansion valve (31) is an electromagnetic thermostatic expansion valve with a diameter of no more than 1 mm. The valve integrates an electromagnetic valve for switching on and off the refrigerant pipeline and a thermostatic expansion valve for automatically adjusting the superheat of the refrigerant.

3. The shared compressor energy storage semiconductor vehicle-mounted refrigerator according to claim 1, characterized in that, The thermoelectric semiconductor module (1) includes a thermoelectric semiconductor chip, a cold end heat sink attached to its cold end, and an internal circulation fan that causes air inside the refrigerator to flow through the cold end heat sink.

4. A control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator, applied to the shared compressor energy storage semiconductor vehicle-mounted refrigerator described in any one of claims 1-3, characterized in that, Includes the following modes: Cooling mode: Open the refrigerator expansion valve (31), request the start of the vehicle compressor (41), start the thermoelectric semiconductor module (1) cooling and internal circulation fan to cool the box and charge the cold storage module (2) at the same time; when the temperature inside the box T refrigerator reaches the set temperature Tset, and the temperature of the cold storage module (2) T cold storage is lower than its phase change temperature Tb-first offset △T0, switch to heat preservation mode; Insulation mode: Request to shut down the vehicle compressor (41) and delay the shutdown of the refrigerator expansion valve (31). The thermoelectric semiconductor module (1) and the internal circulation fan adjust according to the temperature inside the box, and the cold storage module (2) releases cold. When the temperature T of the cold storage module (2) is detected to be higher than its phase change temperature Tb-second offset △T1, switch back to the cooling mode. Heating mode: Start the thermoelectric semiconductor module (1) for heating and the internal circulation fan to heat the inside of the box; Standby mode: The thermoelectric semiconductor module (1) and the internal circulation fan are turned off. After requesting to turn off the vehicle compressor (41), the refrigerator expansion valve (31) is turned off after a delay.

5. The control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator according to claim 4, characterized in that, The values ​​of the first offset △T0 and the second offset △T1 range from 3℃ to 10℃.

6. The control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator according to claim 4, characterized in that, In cooling mode and heat preservation mode, a control signal is generated by PID control algorithm to adjust the input power of thermoelectric semiconductor module (1) and the speed of internal circulation fan respectively, so that the temperature inside the box approaches and is maintained at the set temperature.

7. The control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator according to claim 4, characterized in that, When the refrigerator is running independently, the vehicle compressor (41) operates in low power mode, and the temperature of the refrigerant flowing through the cold plate heat exchanger (3) is lower than the phase change temperature Tb, which can charge the cold storage module (2). When the refrigerator is running in conjunction with the air conditioner or battery cooling, the temperature of the refrigerant flowing through the cold plate heat exchanger (3) is higher than the phase change temperature Tb, and it cannot charge the cold storage module (2).

8. The control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator according to claim 4, characterized in that, It also includes failure modes: When a system fault is detected, shut down the thermoelectric semiconductor module (1) and the internal circulation fan; If the source of the fault is not the vehicle compressor (41), the refrigerator expansion valve (31) will be closed after a delay following the request to shut down the vehicle compressor (41). If the fault source is the vehicle compressor (41), then keep the refrigerator expansion valve (31) open.

9. The control method for a shared compressor energy storage semiconductor vehicle-mounted refrigerator according to claim 4, characterized in that, In the refrigerator's independent cooling mode, if the compressor fails to start within a preset time after requesting to start the vehicle compressor (41), or if the compressor fails to shut down within a preset time after requesting to shut down the vehicle compressor (41) in the heat preservation mode, it is determined to be a compressor malfunction and enters the fault mode.

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