Mobile refrigeration apparatus

Abstract

This invention discloses a portable cooling device and its power supply system. The power supply system includes a power conversion unit, an isolation unit, a control unit, and a main power supply unit. The power conversion unit converts AC power input from an AC input terminal into DC power output from a DC output terminal. The isolation unit has an electrically isolated input terminal and multiple output terminals, and is used to transmit DC power to these output terminals. The control unit is electrically connected to the isolation unit to control the transmission of DC power from the input terminal to the output terminals via electromagnetic coupling. The main power supply unit is electrically connected to a rechargeable battery and a first output terminal of one of the output terminals of the isolation unit, and outputs a boost power supply to power the lithium metal-containing rechargeable battery.

Description

Technical Field

[0001] This invention relates to a refrigeration device, and more particularly to a portable refrigeration device and its power supply system. Prior Technology

[0002] With the increasing popularity of outdoor activities, portable refrigerators play an indispensable role in preserving fresh food and beverages. These products typically use lithium batteries as their power source; however, lithium batteries require a power converter to transform external power into a power source suitable for them.

[0003] In traditional power converter design, digital control loops (or digital power supplies) have become increasingly popular due to their programmable nature. However, these converters have some drawbacks, including slow response, poor control precision, and non-electrically isolated design.

[0004] Furthermore, when digital power supplies handle lithium battery power, the control loop may be limited by the processing speed of the microcontroller (MCU), potentially causing delays in response during power supply and affecting efficiency. In addition, due to the complexity and difficulty in adjusting digital control loops, insufficient control precision may occur, affecting the accuracy and stability of lithium battery power supply. Moreover, existing digital power supplies typically employ non-electrically isolated designs, which are prone to electromagnetic interference, thus affecting the stability and safety of the entire system.

[0005] The above-mentioned defects limit the performance and reliability of digital power supplies in lithium battery-powered applications. Therefore, providing a portable cooling device and its power supply system to solve the above problems is an important current research topic. Summary of the Invention

[0006] In view of the above, the present invention provides a portable cooling device and its power supply system that can improve power supply efficiency, stability and safety.

[0007] To achieve the above objectives, the present invention provides a power supply system for a portable cooling device, comprising a power conversion unit, an isolation unit, a control unit, and a main power supply unit. The power conversion unit has an AC input terminal and a DC output terminal, used to convert AC power input from the AC input terminal into DC power output from the DC output terminal. The isolation unit has an electrically isolated input terminal and multiple output terminals. The input terminal is electrically connected to the DC output terminals to transmit DC power to the output terminals. The control unit is electrically connected to the isolation unit to control the transmission of DC power from the input terminal to the output terminals via electromagnetic coupling. The main power supply unit is electrically connected to a rechargeable battery and a first output terminal of one of the output terminals of the isolation unit, and outputs a boost power supply to power the rechargeable battery, wherein the rechargeable battery is a lithium metal battery.

[0008] In one embodiment of the present invention, the power supply system further includes an auxiliary power supply unit, which is electrically connected to the third output terminal of one of the isolation units and outputs a step-down power supply according to the DC power output by the isolation unit.

[0009] In one embodiment of the present invention, the power supply system further includes a feedback unit, which is electrically connected to both the main power supply unit and the auxiliary power supply unit. The feedback unit generates a detection signal based on the boost power supply and the buck power supply, and transmits the detection signal to the control unit.

[0010] In one embodiment of the present invention, the power supply system further includes an overvoltage protection unit, which is electrically connected to a fourth output terminal of one of the output terminals of the control unit and the isolation unit, and outputs a protection signal to the control unit when the boost power output by the main power supply unit is greater than a preset value.

[0011] In one embodiment of the present invention, the power supply system further includes a surge absorption unit electrically connected between the input terminals of the control unit and the isolation unit to absorb surge voltage or surge current.

[0012] In one embodiment of the present invention, the power supply system further includes a shielding unit that covers the periphery of the power supply system and is electrically connected to a ground terminal of the control unit.

[0013] On the other hand, to achieve the above objectives, the present invention also provides a portable refrigeration device, comprising a main body, a power supply system, and a refrigeration system. The main body has a housing and a cover. The housing has a first space and a second space, and the cover is sealed to an opening in the housing to form a cold-insulating space. The power supply system includes a power conversion unit, an isolation unit, a control unit, and a main power supply unit. The power conversion unit has an AC input terminal and a DC output terminal, used to convert AC power input from the AC input terminal into DC power output from the DC output terminal. The isolation unit has an electrically isolated input terminal and multiple output terminals. The input terminal is electrically connected to the DC output terminals to transmit DC power to the output terminals. The control unit is electrically connected to the isolation unit to control the transmission of DC power from the input terminal to the output terminals via electromagnetic coupling. The main power supply unit is electrically connected to a rechargeable battery and one of the first output terminals of the isolation unit, and outputs a boost power supply to power the rechargeable battery, which is a lithium metal battery. The cooling system is located in the second space and is driven by the rechargeable battery to adjust the temperature of the cooling space.

[0014] As described above, the portable cooling device and its power supply system of the present invention utilize an isolation unit to adopt an independent electrical isolation design for its input and output sides, which can avoid electromagnetic interference between the input and output sides and improve the safety protection level and power supply performance of the lithium battery power supply.

[0015] To make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments are described below in conjunction with the accompanying drawings for detailed explanation. Simple Explanation of the Diagram

[0016] Figure 1 shows a schematic diagram of a portable cooling system according to a preferred embodiment of the present invention. Figure 2 shows a block diagram of the power supply system of a portable cooling system according to a preferred embodiment of the present invention. Implementation

[0017] Referring to Figure 1, a preferred embodiment of the present invention, a portable refrigeration device 10, includes a main body 110, a power supply system 200, a refrigeration system 300, and a rechargeable battery 400. The portable refrigeration device 10 is, for example, a portable refrigerator, which, depending on its purpose, can be divided into small refrigerators for outdoor activities, or refrigerated or frozen containers mounted on locomotives or trucks for cargo transportation.

[0018] As shown in Figure 1, the main body 110 includes a box 111 and a cover 112. The box 111 has a first space 113 and a second space 114, which are separated. The first space 113 can be used to hold items to be preserved, such as fresh food, while the second space 114 is used to house the power supply system 200, the refrigeration system 300, and the rechargeable battery 400. The cover 112 can be sealed with the opening of the box 111 to form a cold-keeping space. In this embodiment, the opening of the first space 113 is exposed outside the box 111, so the cover 112 is sealed with the opening of the first space 113.

[0019] Next, please refer to Figure 2. The power supply system 200 includes a power conversion unit 211, an isolation unit 212, a control unit 213, a main power supply unit 214, an auxiliary power supply unit 215, a feedback unit 216, an overvoltage protection unit 217, a startup unit 218, a surge absorption unit 219, a status detection unit 220, a shutdown unit 221, and a shielding unit 222.

[0020] The power conversion unit 211 has an AC input terminal 211a and a DC output terminal 211b. The power conversion unit 211 converts the AC power input from the AC input terminal 211a into DC power and outputs it from the DC output terminal 211b. Therefore, the power conversion unit 211 is an AC-DC converter, or an adapter.

[0021] The isolation unit 212 has an electrically isolated input terminal 212a and multiple output terminals, including a first output terminal 212b, a second output terminal 212c, a third output terminal 212d, and a fourth output terminal 212e. The input terminal 212a is electrically connected to the DC output terminal 211b to transmit DC power to these output terminals. In this embodiment, the isolation unit 212 includes a coupling element that transmits electrical energy from the input terminal 212a to the output terminals via electromagnetic coupling. For example, the isolation unit 212 may be an isolation transformer, where its input winding and output winding are electrically isolated and have different grounding terminals.

[0022] The control unit 213 is electrically connected to the input terminal 212a and the second output terminal 212c of the isolation unit 212, respectively, to control the transmission of DC power from the input terminal 212a to the output terminals via electromagnetic coupling. In addition, the isolation unit 212 also provides the power required by the control unit 212 through the second output terminal 212c.

[0023] The main power supply unit 214 is electrically connected to both the rechargeable battery 400 and the first output terminal 212b of the isolation unit 212. The main power supply unit 214 is, for example, a boost circuit, which outputs a boosted power supply based on the DC power output from the isolation unit 212 to power (charge) the rechargeable battery 400. In this embodiment, the rechargeable battery 400 is a lithium metal-containing battery, including but not limited to lithium-ion polymer batteries, ternary lithium batteries, or lithium iron phosphate batteries.

[0024] The auxiliary power supply unit 215 is electrically connected to the third output terminal 212d of the isolation unit 212. The auxiliary power supply unit 215 is, for example, a bulk circuit that outputs a stepped-down power supply based on the DC power output from the isolation unit 212 to provide the power required by electronic devices that are charged via, for example, a USB or Type-C interface.

[0025] The feedback unit 216 is electrically connected to both the main power supply unit 214 and the auxiliary power supply unit 215. The feedback unit 216 detects the voltage of the boost power output from the main power supply unit 214 and, in conjunction with the buck power provided by the auxiliary power supply unit 215, generates a detection signal for the voltage of the boost power output from the main power supply unit 214, and transmits this detection signal to the control unit 213. Notably, the control unit 213 adjusts the duty cycle of the input terminal 212a of the isolation unit 212 based on the detection signal to change the voltage of the boost power output from the main power supply unit 214.

[0026] The overvoltage protection unit 217 is electrically connected to the fourth output terminal 212e of both the control unit 213 and the isolation unit 212. When the boost power output from the main power supply unit 214 exceeds a preset value, the overvoltage protection unit 217 outputs a protection signal to the control unit 213 to provide overvoltage protection for the control unit 213. Overvoltage protection may include, but is not limited to, cutting off the system's power supply or forcibly reducing the voltage. In this embodiment, the fourth output terminal 212e and the input terminal 212a of the isolation unit 212 are in phase.

[0027] The starting unit 218 is electrically connected to the control unit 213 and the power conversion unit 211 respectively, so as to start the control unit 213 by the power provided by the power conversion unit 211.

[0028] The surge absorption unit 219 is electrically connected between the control unit 213 and the input terminal 212a of the isolation unit 212 to absorb the surge voltage or surge current generated when the control unit 213 controls the input terminal 212a of the isolation unit 212 to transmit electrical energy in the form of electromagnetic coupling.

[0029] The status detection unit 220 is electrically connected to the main power supply unit 214 and the auxiliary power supply unit 215, respectively. The status detection unit 220 detects whether the output status of the main power supply unit 214 and the auxiliary power supply unit 215 is abnormal, and when an abnormality is detected, it feeds back to the control unit 213 so that the control unit 213 can handle the abnormality.

[0030] The shutdown unit 221 is electrically connected to the status detection unit 220 to provide feedback to the control unit 213 when the output status of the main power supply unit 214 or the auxiliary power supply unit 215 is abnormal, so that the control unit 213 can shut down the main power supply unit 214 or the auxiliary power supply unit 215.

[0031] The shielding unit 222 is a conductive planar element, such as, but not limited to, a metal plate or metal mesh. It can be placed around the components in the power supply system 200 that require noise isolation and is electrically connected to the ground terminal of the control unit 213 to guide external noise or electromagnetic waves generated by the control unit 213 to the ground terminal to reduce signal noise.

[0032] Referring again to Figure 1, the refrigeration system 300 is located in the second space 114, adjacent to the power supply system 200 and the rechargeable battery 400. The refrigeration system 300 may include a compressor, a drive motor, a condenser, a refrigerant controller, and an evaporator (not shown in the figure). The components of the refrigeration system 300 are interconnected by pipes to form a closed-loop circulation system, and the pipes are filled with refrigerant. The rechargeable battery 400 provides electrical energy to drive the compressor to generate mechanical energy, so that the refrigerant continuously circulates within the system, thereby changing the state of the refrigerant. When the pressure is high, it dissipates heat and cools to a liquid state; when the pressure is low, it evaporates and absorbs heat to a gaseous state, thereby maintaining the temperature of the first space 113.

[0033] In summary, the portable cooling device and its power supply system of this invention, through the design of multi-terminal input and output of the isolation unit, achieve a completely independent electrical isolation state between the input and output sides, avoiding electromagnetic interference between them, improving the safety protection level and power supply performance of the lithium battery power supply, and possessing the advantages of high safety and stable output. The overall design of the power supply system uses an electrically isolated low-power analog power supply to achieve the power output that previously required high-power power supplies in existing technologies, providing a stable power supply to the lithium battery to ensure its rapid and continuous operation.

[0034] The present invention has been disclosed above with reference to embodiments, but it is not intended to limit the present invention. Those skilled in the art to which this invention pertains may make some modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

[0035] 10: Portable refrigeration equipment 110:Ontology 111: Box 112: Cover 113: First Space 114: Second Space 200: Power Supply System 211: Power Conversion Unit 211a: AC input terminal 211b: DC output terminal 212: Isolation Unit 212a: Input terminal 212b: First output terminal 212c: Second output terminal 212d: Third output terminal 212e: Fourth output terminal 213: Control Unit 214: Main Power Supply Unit 215: Auxiliary power supply unit 216: Feedback Unit 217: Overvoltage Protection Unit 218: Start-up Unit 219: Surge Absorption Unit 220: Status Detection Unit 221: Shutdown Unit 222: Shielding Unit 300: Refrigeration System 400: Rechargeable battery

Claims

1. A portable refrigeration device, comprising: a main body having a housing and a cover, the housing having a first space and a second space, and the cover being sealed to an opening of the housing to form a cold-insulating space; a power supply system disposed in the second space, comprising: a power conversion unit having an AC input terminal and a DC output terminal, for converting an AC power input from the AC input terminal into a DC power output from the DC output terminal; an isolation unit having an input terminal and a plurality of output terminals, the input terminal and the output terminals being electrically isolated, wherein the input terminal is electrically connected to the DC output terminals to transmit the DC power to the output terminals; A control unit is electrically connected to the isolation unit to control the transmission of DC power from the input terminal to the output terminals via electromagnetic coupling; a main power supply unit is electrically connected to a rechargeable battery and a first output terminal of one of the output terminals of the isolation unit, and outputs a boost power supply to power the rechargeable battery, wherein the rechargeable battery is a lithium metal battery; and a refrigeration system is disposed in the second space and driven by the rechargeable battery to adjust the temperature of the refrigerated space.

2. The portable cooling device as claimed in claim 1, wherein the power supply system further includes an auxiliary power supply unit electrically connected to a third output terminal of one of the isolation units, and outputs a step-down power supply based on the DC power output by the isolation unit.

3. The portable cooling device as described in claim 2, wherein the power supply system further includes a feedback unit electrically connected to both the main power supply unit and the auxiliary power supply unit, wherein, The feedback unit generates a detection signal based on the boost power supply and the buck power supply, and transmits the detection signal to the control unit.

4. The portable cooling device as claimed in claim 1, wherein the power supply system further comprises: an overvoltage protection unit electrically connected to a fourth output terminal of one of the output terminals of the control unit and the isolation unit, and outputting a protection signal to the control unit when the boost power output from the main power supply unit exceeds a preset value; and a surge absorption unit electrically connected between the input terminal of the control unit and the isolation unit to absorb surge voltage or surge current.

5. The portable cooling device as claimed in claim 1, wherein the power supply system further includes a shielding unit that covers the periphery of the power supply system and is electrically connected to a ground terminal of the control unit.

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