High-voltage distribution box with strong cooling capability and control method thereof

Abstract

The invention discloses a high-voltage distribution box with strong cooling capacity and a control method thereof. The high-voltage distribution box comprises a heat dissipation system which comprises a flat-plate-shaped semiconductor, a passive radiator and a fan-type active radiator; an electronic switch; and a plurality of high-voltage electrical elements. And the semiconductor heat dissipation system is arranged at the bottom of the high-voltage distribution box and is in close contact with the power battery lower shell. The battery management system controls on and off of the heat dissipation system according to data of the temperature sensor or the current sensor. The semiconductor with the Peltier effect is introduced to cool the electrical element, high-efficiency and low-cost cooling is achieved, the working temperature of the electrical element is reduced, the service life is prolonged, and the current passing capacity is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electric vehicles, and in particular to a high-voltage distribution box with strong cooling capability and a control method thereof. Background Art

[0002] With the rapid development of new energy vehicles, the high-voltage distribution box is a key component of the electric system of electric vehicles. Its performance and reliability directly affect the performance and safety of the entire vehicle. In the prior art, the cooling methods of the high-voltage distribution box are mainly air cooling and liquid cooling.

[0003] Chinese patent CN 107069468 A discloses a high-voltage distribution box that uses a fan for cooling. However, this technology has the following disadvantages: first, the fan cooling power is small, and in extreme cases, it may not be possible to reduce the temperature of the electrical components in the distribution box to an appropriate value in time; second, the fan cooling capacity is low, which means that it needs to be turned on for a longer time to reduce the same temperature, which will consume more vehicle endurance; finally, the fan on / off control logic is heavily dependent on the temperature sensor in the electrical component space in the distribution box, which will increase additional costs for large-scale mass production applications.

[0004] Chinese patents CN 114360965 A and CN 209402918 U disclose a high-voltage power distribution box using liquid cooling. However, this method has the following disadvantages: First, an additional liquid cooling plate or cooler is required, which increases the difficulty and cost of manufacturing due to the increase in the number of parts and installation matching issues; second, the design of the liquid cooling plate flow channel and the selection of pipelines also need to comprehensively consider the position arrangement of the heat-generating components, the selection of the vehicle thermal management water pump and other aspects, which increases the difficulty of design and development; finally, in order to improve the cooling conduction efficiency, the heat-generating high-voltage components need to be fitted with the liquid cooling plate, so the liquid cooling plate needs to be designed with an insulation layer, and the liquid cooling plate and high-voltage components such as the busbar need to be equipped with insulating thermal pads, etc., in order to improve the high-voltage safety of the power distribution and ensure electrical safety. These insulation protection measures also invisibly increase the product cost.

[0005] Therefore, the existing high-voltage distribution box cooling method has problems such as low cooling efficiency, high cost, and complex design, and a new cooling solution is urgently needed to solve these problems. Summary of the invention

[0006] The purpose of the present invention is to provide a high-voltage distribution box with strong cooling capability and a control method thereof, aiming to solve the problems of low cooling efficiency, high cost and complex design of the high-voltage distribution box in the prior art.

[0007] To achieve the above objectives, in a first aspect, the present invention provides a high-voltage distribution box with strong cooling capability, comprising:

[0008] High voltage distribution box body;

[0009] A heat dissipation system is arranged in the body of the high-voltage distribution box, and the heat dissipation system includes a flat-plate semiconductor, a passive heat sink and a fan-type active heat sink; wherein the passive heat sink is in close contact with the cold end plane of the flat-plate semiconductor, and the fan-type active heat sink is arranged above the passive heat sink;

[0010] An electronic switch for controlling the cooling system to be turned on and off;

[0011] Wherein, the hot end plane of the flat-plate-shaped semiconductor is exposed to the outside and is located at the lowest position of the high-voltage distribution box;

[0012] Whether to start the cooling system is determined by the vehicle's battery management system.

[0013] In some embodiments of the present invention, the positive electrode of the flat-plate semiconductor and the positive electrode of the fan-type active heat sink are connected in parallel and then connected to the negative terminal of the electronic switch;

[0014] The negative electrode of the flat semiconductor and the negative electrode of the fan-type active radiator are connected in parallel and then connected to the negative terminal of the battery;

[0015] The positive terminal of the electronic switch is connected to the positive terminal of the battery.

[0016] In some embodiments of the present invention, the electronic switch has two communication terminals, which are respectively connected to two communication terminals of the battery management system and are used to receive a switch instruction sent by the battery management system.

[0017] In some embodiments of the present invention, it further includes high-voltage electrical components and low-voltage electrical components disposed in the high-voltage distribution box body;

[0018] Among them, electrical components with relatively large heat generation are placed near the air outlet of the heat dissipation system.

[0019] In some embodiments of the present invention, the high voltage distribution box further comprises:

[0020] A temperature sensor disposed in the high-voltage distribution box body is used to obtain the temperature of the electrical components;

[0021] The battery management system compares the real-time temperature obtained by the temperature sensor with the cooling threshold temperature of each component to determine whether to turn on or off the heat dissipation system.

[0022] In some embodiments of the present invention, the high voltage distribution box further comprises:

[0023] A current sensor disposed in the high-voltage distribution box body is used to obtain current data;

[0024] The battery management system determines whether to turn on or off the heat dissipation system according to the current data obtained by the current sensor.

[0025] In a second aspect, the present invention provides a control method for the above-mentioned high-voltage distribution box with strong cooling capability, comprising:

[0026] Obtain temperature data inside the high-voltage distribution box;

[0027] comparing the temperature data with a preset cooling threshold temperature;

[0028] When the temperature data is higher than the cooling threshold temperature, controlling the semiconductor heat dissipation system to turn on;

[0029] When the temperature data is lower than the cooling threshold temperature, the semiconductor heat dissipation system is controlled to be closed.

[0030] In some embodiments of the present invention, obtaining temperature data in the high-voltage distribution box includes:

[0031] The temperature data of the electrical components is obtained through the temperature sensor installed in the high-voltage distribution box.

[0032] In some embodiments of the present invention, the control method further includes:

[0033] When no temperature sensor is provided in the high-voltage distribution box, current data is obtained through a current sensor;

[0034] estimating the temperature inside the high-voltage distribution box according to the current data;

[0035] comparing the estimated temperature to a preset cooling threshold temperature;

[0036] The semiconductor cooling system is controlled to be turned on and off according to the comparison result.

[0037] In some embodiments of the present invention, the temperature in the high-voltage distribution box is estimated based on the current data using the following formula:

[0038] T=T0+k·I 2 ·R·t

[0039] Where T is the estimated temperature, T0 is the initial temperature, k is the thermal conductivity, I is the current, R is the equivalent resistance, and t is the time.

[0040] In some embodiments of the present invention, different cooling threshold temperatures are set for different high-voltage electrical components.

[0041] The present invention has the following beneficial effects:

[0042] (1) The semiconductor with "Peltier effect" is innovatively introduced as a key component of the heat dissipation system, achieving high-efficiency and low-cost cooling. Compared with the traditional air cooling method, the present invention has a better cooling effect and can more quickly reduce the temperature of the electrical components in the distribution box to an appropriate value; compared with the liquid cooling method, the present invention does not require additional liquid cooling plates or coolers, which simplifies the design and reduces costs.

[0043] (2) By arranging the semiconductor heat dissipation system at the bottom of the high-voltage distribution box and making it in close contact with the lower shell of the power battery, the function of the lower shell of the power battery as a radiator is fully utilized, further improving the heat dissipation efficiency.

[0044] (3) An intelligent control strategy is adopted to dynamically adjust the opening and closing of the cooling system according to the data of the temperature sensor or current sensor, which not only ensures the cooling effect, but also avoids unnecessary energy consumption and improves the endurance of the vehicle.

[0045] (4) Flexible control methods adapt to different application scenarios. For high-voltage distribution boxes equipped with temperature sensors, they can be controlled directly based on temperature data; for low-cost solutions that are not equipped with temperature sensors, the temperature can be estimated and controlled based on current data, meeting product designs with different cost requirements.

[0046] (5) The design of the present invention has wide applicability. In addition to the high-voltage distribution box of power batteries, it can also be applied to the high-voltage distribution box of electric vehicles, the inside of DC-DC, the inside of on-board charging / discharging machines, and other places where direct liquid cooling is not suitable.

[0047] To sum up, the high-voltage distribution box with strong cooling capability and the control method thereof provided by the present invention achieve high-efficiency and low-cost cooling without substantially changing the existing structural design of the high-voltage distribution box, thereby reducing the operating temperature of electrical components and extending their service life, while significantly improving the current passing capacity, thereby providing a new technical solution for improving the performance and reliability of the electrical system of new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments disclosed in the present invention, the drawings of the embodiments are briefly introduced below. These drawings are only used for illustrative purposes and are not intended to limit the protection scope of the present invention.

[0049] Figure 1 is an exploded schematic diagram of a heat dissipation system provided by an embodiment of the present invention;

[0050] Figure 2 is a schematic diagram of the electrical principle of the heat dissipation system provided by an embodiment of the present invention;

[0051] Figure 3A schematic diagram of installing the heat dissipation system provided by an embodiment of the present invention in a power distribution box and a power battery;

[0052] Figure 4 yes Figure 3 AA cross-sectional view in FIG.

[0053] Figure 5 is a schematic diagram of the position of the heat dissipation system provided by an embodiment of the present invention in a power distribution box;

[0054] Figure 6 is a logic block diagram of a control method provided by an embodiment of the present invention;

[0055] Figure 7 It is a logic block diagram of a control method provided by another embodiment of the present invention. DETAILED DESCRIPTION

[0056] The technical solution of the present invention (including the preferred technical solution) is further described in detail below by means of the accompanying drawings and by listing some optional embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0057] Example 1: High-voltage distribution box with strong cooling capability

[0058] like Figures 1 to 5 As shown, this embodiment provides a high-voltage distribution box with strong cooling capability, including a heat dissipation system, an electronic switch 4, a battery 5 and a plurality of high-voltage electrical components.

[0059] In some optional embodiments of the present invention, the heat dissipation system is a semiconductor heat dissipation system.

[0060] The semiconductor heat dissipation system includes a flat semiconductor 1, a passive heat sink 2 and a fan-type active heat sink 3. Figure 1 As shown, the passive radiator 2 is in close contact with the cold end plane of the flat semiconductor 1, and the fan-type active radiator 3 is arranged above the passive radiator 2. When working, the outside of the fan-type active radiator 3 has a large amount of low-temperature cold air for heat dissipation.

[0061] like Figure 2As shown, the negative terminal 42 of the electronic switch 4 is connected in parallel with the positive electrode 11 of the flat semiconductor 1 and the positive electrode 31 of the fan-type active radiator 3. The positive terminal 51 of the battery 5 is connected to the positive terminal 41 of the electronic switch 4, and the negative terminal 52 of the battery 5 is connected in parallel with the negative electrode 12 of the flat semiconductor 1 and the negative electrode 32 of the fan-type active radiator 3. The positive terminal 61 and the negative terminal 62 of the vehicle-mounted battery management system 6 are respectively connected to the positive terminal 51 and the negative terminal 52 of the battery 5, and the communication terminals 63 and 64 of the battery management system 6 are connected to the communication terminals 43 and 44 of the electronic switch 4.

[0062] In this embodiment, low-voltage electrical components such as the semiconductor heat dissipation system, the electronic switch 4 , and the battery management system 6 all operate at a voltage of 12V and can be directly powered by the battery 5 of the vehicle.

[0063] like Figure 3 and Figure 4 As shown, the semiconductor heat dissipation system is arranged at the bottom of the high-voltage distribution box 7, the hot end plane of the flat semiconductor 1 is completely exposed, and its lower surface is at the lowest position of the entire high-voltage distribution box 7. When the distribution box 7 is installed inside the lower shell 8 of the power battery, the hot end plane of the flat semiconductor 1 is in close contact with the upper surface of the lower shell 8. If necessary, materials such as thermal conductive silicone grease can be added between the two surfaces to improve the heat conduction efficiency.

[0064] like Figure 5 As shown, a plurality of high-voltage electrical components are arranged on the upper surface of the semiconductor heat dissipation system. These high-voltage electrical components include a relay 71, a fuse 72, a pre-charge group 73 and a current sensor 74. In this embodiment, electrical components with a larger heat generation (such as relay 71) are placed near the air outlet of the heat dissipation system, and electrical components with a smaller heat generation (such as current sensor 74) are placed slightly further away. More precisely, the temperature of each component can be calculated according to the current condition flowing through the distribution box, and the placement position of each component can be optimized in combination with the radiator power.

[0065] The high-voltage distribution box 7 of this embodiment adopts a closed design. In addition to reserving basic external high and low voltage interfaces, it is as closed as possible to minimize the temperature inside the high-voltage distribution box 7. If necessary, a sealant can be used for processing.

[0066] It should be noted that the use of the heat dissipation system in the present embodiment in the high-voltage distribution box of the power battery is only an example of a typical application, but it is not limited to the high-voltage distribution box of the power battery. Other typical application scenarios include but are not limited to: the high-voltage distribution box of the whole electric vehicle, the inside of the DC-DC, the inside of the on-board charger / discharger, and other occasions where liquid cooling is not suitable for direct use.

[0067] Embodiment 2: Control method of high voltage distribution box with strong cooling capability (based on temperature sensor)

[0068] like Figure 6 As shown, this embodiment provides a control method for the high-voltage distribution box described in Example 1. The method uses the existing temperature sensor in the power battery high-voltage distribution box 7 to obtain the temperature of the electrical components and transmits it to the battery management system 6. The battery management system 6 compares the real-time temperature with the cooling threshold temperature of each component and determines whether to turn the cooling system on or off. The specific steps are as follows:

[0069] Step S201: Acquire temperature data of electrical components through a temperature sensor disposed in the high-voltage distribution box 7;

[0070] Step S202: the battery management system 6 receives the temperature data and compares it with a preset cooling threshold temperature;

[0071] Step S203: When the temperature data is higher than the cooling threshold temperature, the battery management system 6 sends an opening instruction to the electronic switch 4 through the communication terminals 63 and 64 to control the semiconductor cooling system to turn on;

[0072] Step S204: When the temperature data is lower than the cooling threshold temperature, the battery management system 6 sends a shutdown instruction to the electronic switch 4 through the communication terminals 63 and 64 to control the semiconductor heat dissipation system to shut down.

[0073] In this embodiment, different cooling threshold temperatures can be set for different electrical components to meet the heat dissipation requirements of each component. For example, a cooling threshold temperature of 80°C can be set for the relay 71, and a cooling threshold temperature of 70°C can be set for the fuse 72. When the temperature of any component exceeds its corresponding cooling threshold temperature, the semiconductor heat dissipation system will be turned on.

[0074] Embodiment 3: Control method of high voltage distribution box with strong cooling capability (based on current sensor)

[0075] In some low-cost power battery designs, the temperature sensor in the high-voltage distribution box 7 is relatively lacking, and it is unable to provide the temperature of the electrical components, so it is impossible to adjust the cooling system to work or not according to the real-time temperature. However, all power battery high-voltage distribution boxes 7 are designed with current sensors, and these data can be used to adjust the cooling system to work or not. This embodiment provides a control method based on current sensors, and the specific steps are as follows:

[0076] Step S301: obtaining current data through the current sensor 74 disposed in the high-voltage distribution box 7;

[0077] Step S302: the battery management system 6 receives the current data and estimates the temperature inside the high-voltage distribution box 7 according to a preset current-temperature relationship model;

[0078] Step S303: the battery management system 6 compares the estimated temperature with a preset cooling threshold temperature;

[0079] Step S304: when the estimated temperature is higher than the cooling threshold temperature, the battery management system 6 sends an opening instruction to the electronic switch 4 through the communication terminals 63 and 64 to control the semiconductor cooling system to turn on;

[0080] Step S305: When the estimated temperature is lower than the cooling threshold temperature, the battery management system 6 sends a shutdown instruction to the electronic switch 4 through the communication terminals 63 and 64 to control the semiconductor heat dissipation system to shut down.

[0081] In this embodiment, the current-temperature relationship model can be obtained through experimental testing or thermal simulation analysis. For example, the following simplified model can be established:

[0082] T=T0+k·I 2 ·R·t

[0083] Where T is the estimated temperature, T0 is the initial temperature, k is the thermal conductivity, I is the current, R is the equivalent resistance, and t is the time.

[0084] Through this method, even without a temperature sensor, the temperature inside the high-voltage distribution box can be effectively estimated and controlled, thereby reducing the system cost.

[0085] Those skilled in the art will readily appreciate that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, replacements, improvements, etc. made within the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A high voltage distribution box with strong cooling capability, characterized in that: include: High voltage distribution box body; A heat dissipation system is arranged in the high-voltage distribution box body, and the heat dissipation system includes a flat semiconductor, a passive heat sink and a fan-type active heat sink; The passive heat sink is in close contact with the cold end plane of the flat semiconductor, and the fan-type active heat sink is arranged above the passive heat sink; An electronic switch for controlling the cooling system to be turned on and off; Wherein, the hot end plane of the flat-plate-shaped semiconductor is exposed to the outside and is located at the lowest position of the high-voltage distribution box; Whether to start the cooling system is determined by the vehicle's battery management system.

2. The high-voltage distribution box with strong cooling capability according to claim 1 is characterized in that: The positive electrode of the flat-plate semiconductor and the positive electrode of the fan-type active heat sink are connected in parallel and then connected to the negative terminal of the electronic switch; The negative electrode of the flat semiconductor and the negative electrode of the fan-type active radiator are connected in parallel and then connected to the negative terminal of the battery; The positive terminal of the electronic switch is connected to the positive terminal of the battery.

3. The high-voltage distribution box with strong cooling capability according to claim 1 is characterized in that: The electronic switch has two communication terminals, which are respectively connected to two communication terminals of the battery management system and are used to receive switch instructions sent by the battery management system.

4. The high-voltage distribution box with strong cooling capability according to claim 1 is characterized in that: It also includes high-voltage electrical components and low-voltage electrical components arranged in the high-voltage distribution box body; Among them, electrical components with relatively large heat generation are placed near the air outlet of the heat dissipation system.

5. The high-voltage distribution box with strong cooling capability according to claim 1 is characterized in that: The high voltage distribution box also includes: A temperature sensor disposed in the high-voltage distribution box body is used to obtain the temperature of the electrical components; The battery management system compares the real-time temperature obtained by the temperature sensor with the cooling threshold temperature of each component to determine whether to turn on or off the heat dissipation system.

6. The high-voltage distribution box with strong cooling capability according to claim 1 is characterized in that: The high voltage distribution box also includes: A current sensor disposed in the high-voltage distribution box body is used to obtain current data; The battery management system determines whether to turn on or off the heat dissipation system according to the current data obtained by the current sensor.

7. A control method for a high-voltage distribution box with strong cooling capability as claimed in any one of claims 1 to 6, characterized in that: include: Obtain temperature data inside the high-voltage distribution box; comparing the temperature data with a preset cooling threshold temperature; When the temperature data is higher than the cooling threshold temperature, controlling the semiconductor heat dissipation system to turn on; When the temperature data is lower than the cooling threshold temperature, the semiconductor heat dissipation system is controlled to be closed.

8. The control method according to claim 6, characterized in that: The obtaining of temperature data in the high-voltage distribution box comprises: The temperature data of the electrical components is obtained through the temperature sensor installed in the high-voltage distribution box.

9. The control method according to claim 6, characterized in that: The control method further comprises: When no temperature sensor is provided in the high-voltage distribution box, current data is obtained through a current sensor; estimating the temperature inside the high-voltage distribution box according to the current data; comparing the estimated temperature to a preset cooling threshold temperature; The semiconductor cooling system is controlled to be turned on and off according to the comparison result.

10. The control method according to claim 6, characterized in that: Different cooling threshold temperatures are set for different high voltage electrical components.

Images