High-low voltage integrated junction box for fuel cell loading

Abstract

The utility model discloses a high-low voltage integrated junction box for loading a fuel cell, which comprises a high-voltage input port, a high-voltage output port, a low-voltage input port and a high-voltage output port, the high-pressure output port is in butt joint with a whole vehicle high-pressure port; the low-voltage output port is butted with the fuel cell for low-voltage power supply; the high-voltage input port and the high-voltage output port are connected through a high-voltage transmission circuit, the high-voltage transmission circuit is provided with a high-voltage distribution area, and the high-voltage distribution area is provided with a first line connected to the high-voltage output port and a second line connected to the low-voltage output port. The second line is provided with a step-down converter used for converting high voltage into low voltage. The high-low voltage integrated junction box is simple in structure, high-low voltage integration is realized, and the problems of low-voltage power supply of a system in the system loading process, power supply of a cooling fan, insufficient high-voltage auxiliary output ports in the system loading process, capacitor electrification during shutdown and the like are solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to fuel cell loading field especially relates to a fuel cell loading high low pressure integral branch box. BACKGROUND

[0002] With the enhancement of global environmental protection consciousness and the transformation of energy structure, hydrogen fuel cell technology, as an important part of clean energy solution, is gradually showing its great potential in the field of transportation and energy supply. Hydrogen fuel cell converts the chemical energy of hydrogen and oxygen into electrical energy through electrochemical reaction, which has high energy conversion efficiency and almost no pollution during operation, and is an effective way to realize low-carbon transportation and green energy supply.

[0003] In the development of fuel cell vehicles, aircraft, trains and other transportation tools, and fixed power stations, the integration and application of fuel cell technology face a series of technical challenges. In particular, based on the existing mature pure electric vehicle parts, the development mode of fuel cell vehicle can shorten the development cycle and reduce the cost to a certain extent, but at the same time, some key problems are exposed, especially in the adaptability of electrical system and thermal management system.

[0004] Specifically, after the introduction of fuel cell system, the newly added electrical equipment significantly increases the power demand of the vehicle or equipment, which puts higher requirements on the original low-voltage power supply system. The traditional low-voltage power supply design often cannot meet the power demand of the newly added electrical equipment of fuel cell vehicle, especially under high load working conditions such as starting and accelerating, which may cause voltage fluctuation, unstable power supply and other problems, affecting the stable operation of fuel cell system and the performance of the whole vehicle.

[0005] In addition, a large amount of heat will be generated during the operation of fuel cell system, which must be maintained within a safe range through effective heat dissipation measures to ensure the long-term reliable operation of the system. The stability and efficiency of the power supply of the system cooling fan as a key cooling component are directly related to the cooling effect of the fuel cell. However, at present, the power supply scheme of the system cooling fan during the loading of fuel cell is often not fully considered and optimized, which has problems such as insufficient power supply, complex line, difficult maintenance and so on, which seriously restricts the efficient cooling and overall performance of fuel cell system.

[0006] Therefore, in view of the above existing problems, it is urgent to develop an innovative electrical and thermal management system solution. The scheme should effectively improve the power output capacity of low-voltage power supply, ensure the stable power supply of newly added electrical equipment of fuel cell vehicle, optimize the power supply design of system cooling fan, simplify the layout of line, improve the cooling efficiency, so as to ensure the safe and efficient operation of fuel cell system, and promote the application and development of hydrogen fuel cell technology in a wider field. SUMMARY

[0007] The utility model provides a kind of fuel cell trucking high-low voltage integrated distribution box, simple structure can solve the electricity demand of new electrical components when fuel cell trucking.

[0008] To achieve the above purpose, the utility model mainly provides the following technical scheme:

[0009] The fuel cell trucking high-low voltage integrated distribution box includes: high-pressure input port, for interfacing fuel cell power output port;High-pressure output port, for interfacing whole vehicle high-pressure port;Low-voltage output port, for interfacing fuel cell low-voltage power supply;

[0010] The high-pressure input port and high-pressure output port are connected by high-voltage transmission circuit, the high-voltage transmission circuit has high-voltage distribution area, the high-voltage distribution area has the first line connected to the high-pressure output port, and the second line connected to the low-voltage output port, the second line is provided with voltage reduction converter for converting high voltage to low voltage.

[0011] Through the explicit high pressure and low pressure interface design, the rational distribution and conversion of electric energy are realized, and the compatibility between fuel cell system and other electrical components is ensured. In particular, as preferred, the voltage input by the high-pressure input port is 750V;The voltage output by the low-voltage output port is 24V, which meets the standard output voltage of fuel cell system, and also meets the conventional demand of low-voltage electrical equipment.

[0012] As preferred, it also includes high-voltage pre-charging circuit;One of the wires of the high-voltage transmission circuit is provided with a first switch, and the high-voltage pre-charging circuit includes a pre-charging line connected between the two ends of the first switch, and the pre-charging line is provided with a second switch and a pre-charging resistor;When high voltage is applied to the whole vehicle, the first switch is disconnected, and the second switch is opened, to charge the capacitor in the fuel cell auxiliary components with small current. The design of pre-charging circuit improves the stability and safety of the system, and ensures that the capacitor can smoothly transition to normal working state when high voltage is applied.

[0013] Further, by reasonably setting the resistance value of the pre-charging resistor to 150~750Ω;The current value when charging the capacitor in the fuel cell auxiliary components with small current is 1~5A, which further optimizes the charging process and prolongs the service life of the capacitor.

[0014] The utility model discloses fuel cell is loaded with high and low pressure integral distribution box, still includes discharge circuit, the discharge circuit includes the discharge wire of two electric wires of two ends connection high pressure delivery circuit, is equipped with third switch and discharge resistance on discharge wire, when fuel cell shutdown, through opening third switch and connect the discharge circuit, release the electric quantity of the condenser in high pressure auxiliary component such as air compressor driver, high pressure water pump, positive temperature coefficient thermistor (PTC) etc.

[0015] Further, the resistance value of the discharge resistor is 1000-2000Ω, ensuring the smoothness and efficiency of the discharge process.

[0016] The fuel cell loading high and low pressure integral distribution box also includes an auxiliary high voltage output port, which is used to connect the power supply of auxiliary components; the high voltage distribution area has a third line connected to the auxiliary high voltage output port. The design of the auxiliary high voltage output port increases the flexibility and scalability of the system, enabling the fuel cell system to better adapt to the needs of different vehicle models and configurations.

[0017] Further, the auxiliary components are air compressor drivers, high pressure water pumps, PTCs and cooling fans of the fuel cell, and the cooling fans ensure the heat dissipation effect and operation stability of the system.

[0018] Compared with the prior art, the fuel cell loading high and low pressure integral distribution box realizes high and low voltage integration, solves the problems of low voltage power supply, cooling fan power supply, insufficient high voltage auxiliary output port during system loading, and capacitor charging during shutdown. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is an internal schematic diagram of the high and low voltage integral distribution box.

[0020] In the figure, R2 is a pre-charge resistor, R1 is a discharge resistor, K3 is a first switch, K2 is a second switch, K1 is a third switch, 1 is a high voltage input port, 2 is a high voltage output port, 3 is a discharge circuit, 4 is a high voltage pre-charge circuit, 5 is a high voltage distribution area, 6 is a step-down converter, 7 is an auxiliary high voltage output port, and 8 is a low voltage output port. DETAILED DESCRIPTION

[0021] As shown in Figure 1 The fuel cell loading high and low pressure integral distribution box provided by the utility model includes: a high voltage input port 1 for connecting a fuel cell power output port; a high voltage output port 2 for connecting a vehicle high voltage port; and a low voltage output port 8 for connecting a fuel cell low voltage power supply;

[0022] The high-voltage input port 1 is connected with the high-voltage output port 2 through a high-voltage transmission circuit, the high-voltage transmission circuit has a high-voltage distribution area 5, the high-voltage distribution area 5 has a first line connected to the high-voltage output port 2, and a second line connected to the low-voltage output port 8, and the second line is provided with a voltage reduction converter 6 for converting high voltage into low voltage.

[0023] In order to realize reasonable distribution and conversion of electric energy and ensure compatibility between the fuel cell system and other electrical components, the voltage input by the high-voltage input port in the utility model can be set to 750V; the voltage output by the low-voltage output port is set to 24V, which can meet the standard output voltage of the fuel cell system and also meet the conventional demand of low-voltage electrical equipment.

[0024] In order to ensure that the capacitor can smoothly transition to the normal working state when the high voltage is applied, the high-low voltage integrated distribution box for fuel cell vehicle provided by the utility model further designs a high-voltage pre-charging circuit 4; one of the wires of the high-voltage transmission circuit 4 is provided with a first switch K3, the high-voltage pre-charging circuit 4 includes a pre-charging line connected between the two ends of the first switch K3, and the pre-charging line is provided with a second switch K2 and a pre-charging resistor R2; when the whole vehicle is powered on, the first switch K3 is disconnected, and the second switch K2 is opened, so as to charge the capacitor in the fuel cell auxiliary component with a small current, thereby improving the stability and safety of the system.

[0025] In order to further optimize the charging process and prolong the service life of the capacitor, in the utility model, the resistance value of the pre-charging resistor R2 is set to 150~750Ω; the current value when charging the capacitor in the fuel cell auxiliary component with a small current is set to 1~5A.

[0026] In order to avoid the safety hazards that may be caused by the charging of the capacitor, the high-low voltage integrated distribution box for fuel cell vehicle in the utility model further includes a discharge circuit 3, the discharge circuit 3 includes a discharge line connected between the two wires of the high-voltage transmission circuit, and the discharge line is provided with a third switch K1 and a discharge resistor R1; in the utility model, the resistance value of the discharge resistor can be set to 1000~2000Ω to ensure the smoothness and efficiency of the discharging process; when the fuel cell is shut down, the discharge circuit 3 is connected by opening the third switch K1, and the electric quantity of the capacitor in the high-voltage auxiliary component such as the air compressor driver, the high-pressure water pump and the PTC is discharged.

[0027] The utility model discloses fuel cell loading high -low pressure integral distribution box still includes auxiliary high -pressure output 7, and auxiliary high -pressure output 7 is used for butt joint air compressor drive, high -pressure water pump, PTC, heat dissipation fan etc.

[0028] The utility model discloses when using, whole car is after on high -voltage, current enters high -pressure distribution area 5 through high -voltage output 2, and after the drop converter 6 drops to 24V, and through low -voltage output 8 for fuel cell low -voltage power supply, current enters high -pressure distribution area 5 through high -voltage output 2, and after auxiliary high -voltage output 7 is powered (if heat dissipation fan is low -voltage fan, then the drop converter that provides the electric energy for low -voltage fan is added outside high -low pressure integral distribution box) for air compressor drive, high -pressure water pump, PTC and heat dissipation fan etc., and whole car is after on high -voltage, and third switch K1 breaks, and second switch K2 attracts, and through pre -charge resistance R2 for fuel cell auxiliary component high -pressure water pump, PTC, air compressor drive, direct current -direct current converter component's capacitor carries out small -current charging, and when first switch K3 front -back pressure difference is similar, and attract first switch K3, and break second switch K2. When fuel cell shutdown, break first switch K3, and attract third switch K1, and through discharge resistance R1, and high -voltage auxiliary component internal capacitor electric quantity is released.

Claims

1. A fuel cell vehicle-mounted high-low voltage integrated distribution box, characterized by comprising: include: The high-voltage input port is used to connect to the fuel cell power generation output port; High-voltage output port, used to connect to the high-voltage port of the vehicle; The low-voltage output port is used to connect to the low-voltage power supply of the fuel cell; The high-voltage input port and the high-voltage output port are connected by a high-voltage transmission circuit. The high-voltage transmission circuit has a high-voltage distribution area. The high-voltage distribution area has a first line connected to the high-voltage output port and a second line connected to the low-voltage output port. The second line is provided with a step-down converter for converting high voltage to low voltage.

2. The fuel cell vehicle high and low voltage integrated distribution box according to claim 1, characterized by The high-voltage input port receives a voltage of 750V; the low-voltage output port outputs a voltage of 24V.

3. The fuel cell vehicle high and low voltage integrated distribution box of claim 1, wherein It also includes a high-voltage pre-charging circuit; A first switch is provided on one of the wires of the high-voltage transmission circuit, and the high-voltage pre-charging circuit includes a pre-charging wire connecting the two ends of the first switch, and a second switch and a pre-charging resistor are provided on the pre-charging wire. When the vehicle is powered by high voltage, the first switch is turned off and the second switch is turned on, charging the capacitor in the fuel cell auxiliary components with a small current.

4. The fuel cell vehicle high and low voltage integrated distribution box according to claim 3, characterized by The resistance of the pre-charge resistor is 150~750Ω; the current value for charging the capacitor in the fuel cell auxiliary component with a small current is 1~5A.

5. The fuel cell vehicle high and low voltage integrated distribution box of claim 1, wherein It also includes a discharge circuit, which includes a discharge line with two wires connected at both ends to the high-voltage transmission circuit, and a third switch and a discharge resistor are provided on the discharge line. When the fuel cell is shut down, the discharge circuit is activated by turning on the third switch, releasing the charge in the capacitor of the high-voltage auxiliary component.

6. The fuel cell vehicle high and low voltage integrated distribution box of claim 5, wherein The resistance of the discharge resistor is 1000~2000Ω.

7. The fuel cell vehicle high and low voltage integrated distribution box of claim 1, wherein The integrated high and low voltage junction box for fuel cell vehicle installation also includes an auxiliary high voltage output port, which is used to connect to auxiliary components for power supply. The high-voltage distribution area has a third line connected to the auxiliary high-voltage output port.

8. The fuel cell vehicle high and low voltage integrated distribution box of claim 7, wherein The auxiliary components are the air compressor driver, high-pressure water pump, positive temperature coefficient thermistor, or cooling fan of the fuel cell.

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