Power system for power-assisted bicycle

Abstract

The present invention provides a power system of a power-assisted bicycle, the power system includes a hydrogen storage tank, a fuel cell device, a control device, and a driving device. The power-assisted bicycle has a frame, and the frame specifically includes: a front oblique beam, a connecting pedal, and a main vertical pipe connected in sequence, the main vertical pipe and the connecting pedal are hollow inside, and an air inlet and an air outlet are provided on the main vertical pipe, so that a first air flow channel is formed inside the main vertical pipe, and the hydrogen storage tank is arranged on the inner wall of the main vertical pipe; the fuel cell device specifically includes: a fuel cell stack and an exhaust hood, the fuel cell stack is arranged in the connecting pedal, and a second air flow channel is provided in the exhaust hood, one end of the second air flow channel is connected to the air outlet of the fuel cell stack, and the other end is connected to the air inlet on the main vertical pipe; wherein, the hot air discharged from the fuel cell stack enters the first air flow channel through the second air flow channel, and is discharged from the exhaust port after flowing through the outer surface of the hydrogen storage tank. The waste heat generated when the fuel cell stack is running is utilized to achieve heat compensation.

Description

Technical Field

[0001] The present invention relates to the technical fields of power systems of electric bicycles, hydrogen storage technology and fuel cell technology, and in particular to a power system of an electric power-assisted bicycle. Background Art

[0002] Hydrogen energy is considered to be an ideal clean energy source with the advantages of light weight, abundant reserves, and environmental friendliness. The main industrial chain of hydrogen energy includes upstream hydrogen preparation, midstream hydrogen transportation and storage, and downstream hydrogen refueling stations, hydrogen fuel cells and applications. Midstream hydrogen storage includes high-pressure gaseous hydrogen storage, low-temperature liquid hydrogen storage, and solid hydrogen storage. High-pressure gaseous hydrogen storage is widely used, simple and easy, low-cost, and fast in hydrogen charging and discharging, but it requires heavy pressure-resistant containers, consumes a lot of hydrogen compression work, and has unsafe factors such as hydrogen leakage and container explosion. Low-temperature liquid hydrogen storage is widely used in hydrogen refueling stations around the world, but its application in vehicle-mounted systems is immature and poses safety risks. In addition, due to technical limitations, the cost of domestic liquid hydrogen applications is very high.

[0003] In the context of advocating energy conservation, emission reduction and low-carbon travel, bicycle power systems, buses, subways, light rail and other public transportation are undoubtedly the preferred means of travel. Among them, the bicycle power system has an irreplaceable special status in the existing public transportation system, playing the role of connecting the destination with subway stations and bus stops. The hydrogen energy-assisted bicycle power system using low-pressure solid hydrogen storage as the hydrogen source has become an ideal choice for green, low-carbon, safe and environmentally friendly travel in the economic society. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0005] In view of this, one object of the present invention is to provide a power system for a power-assisted bicycle.

[0006] In order to achieve the above-mentioned purpose, the technical solution of the present invention provides a power system of a power-assisted bicycle, the power system includes a hydrogen storage tank, a fuel cell device, a control device, and a drive device, the hydrogen storage tank supplies hydrogen to the fuel cell device through a hydrogen supply pipeline, and the fuel cell device supplies electric energy to the hydrogen storage tank, the drive device and the control device respectively through a power supply line; the power-assisted bicycle has a frame, and the frame specifically includes: a front oblique beam, a connecting pedal, and a main vertical pipe connected in sequence, the main vertical pipe and the connecting pedal are hollow inside, and an air inlet and an air outlet are provided on the main vertical pipe, so that a first The fuel cell device specifically comprises: a fuel cell stack and an exhaust hood, wherein the fuel cell stack is arranged in a connecting pedal, and a second air duct for air flow is arranged in the exhaust hood, wherein one end of the exhaust hood is connected to the fuel cell stack, and the other end is connected to the main riser through the top wall of the connecting pedal, so that one end of the second air duct is connected to the air outlet of the fuel cell stack, and the other end is connected to the air inlet on the main riser; wherein the hot air discharged from the fuel cell stack enters the first air duct through the second air duct, and is discharged from the exhaust port after flowing through the hydrogen storage tank.

[0007] Furthermore, the air inlet is arranged at the bottom of the main vertical pipe, and the air outlet is arranged at the top of the main vertical pipe. Along the direction from the air outlet of the fuel cell stack to the air inlet of the main vertical pipe, the cross section of the second air flow channel gradually decreases, and the inner wall of the exhaust cover has a smooth transition.

[0008] Furthermore, the power system of the power-assisted bicycle also includes: an electric heating element, which is coated on the outer surface of the hydrogen storage tank; a heat insulation layer, which is arranged between the hydrogen storage tank and the inner wall of the main riser; the electric heating element is electrically connected to the control device, and the fuel cell device supplies power to the electric heating element through the control device; preferably, the electric heating element is a strip-shaped heating strip; or the electric heating element is a sheet-shaped heating sheet.

[0009] Furthermore, the fuel cell device also includes: a fan, which is arranged on the air outlet of the fuel cell stack; an air inlet and an air outlet are respectively arranged on two opposite surfaces of the fuel cell stack; the air outlet of the fan is connected to the second air flow channel, and the air flows from the air outlet to the second air flow channel under the drive of the fan; a hydrogen inlet and a hydrogen outlet are respectively arranged at the lower and upper parts of one side of the fuel cell stack, and an exhaust solenoid valve is arranged on the hydrogen outlet, and a drain outlet is arranged at the bottom of the connecting pedal, and the reaction gas and water discharged from the hydrogen outlet are discharged through the drain outlet.

[0010] Furthermore, a bottle mouth valve is provided on the bottle mouth of the hydrogen storage tank, the first end of the hydrogen supply pipeline is connected to the hydrogen storage tank through the bottle mouth valve, and the second end is connected to the hydrogen inlet port, and a pressure regulating valve, a gas pressure sensor, and an air intake solenoid valve are provided in sequence on the hydrogen supply pipeline from the first end to the second end. The power system of the power-assisted bicycle also has a seat, which is arranged at the top of the main riser, and the control device specifically includes: a fuel cell controller, a vehicle controller, a battery, a central control device, and a display screen that are electrically connected to each other; the fuel cell controller, the vehicle controller, and the battery are arranged in the connecting pedal, and the central control device is arranged in the seat, and the battery provides a starting power supply for the fuel cell controller and the vehicle controller.

[0011] Furthermore, the power system of the power-assisted bicycle also includes: a vehicle lock, which is electrically connected to the central control device; the display screen obtains unlocking or locking information and transmits it to the central control device, and the central control device controls the vehicle lock to open according to the unlocking information obtained, or controls the vehicle lock to close according to the locking information obtained.

[0012] Furthermore, the central control device includes a main control module and a GPRS module; the main control module is electrically connected to the gas pressure sensor, the drive device, the GPRS module, and the display screen, respectively, so as to collect data such as the gas pressure of the hydrogen storage tank, the current and voltage of the drive device, and transmit them to the display screen for display; the GPRS module is used for vehicle positioning and networking, and the alarm information is sent to the system background through the GPRS module.

[0013] Furthermore, the power system of the power-assisted bicycle also includes: a temperature sensor arranged on the fuel cell stack, a patrol line electrically connected to the stack pole pieces of the fuel cell stack and the fuel cell controller respectively, and the fuel cell controller is electrically connected to the drive device, the gas pressure sensor, the air intake solenoid valve, the fan, the temperature sensor, the patrol line and the air outlet solenoid valve respectively; wherein the fuel cell controller controls the opening or closing of the air intake solenoid valve and the air outlet solenoid valve according to the data information obtained from the gas pressure sensor, the temperature sensor and the patrol line; the fuel cell controller controls the heating power of the electric heating element according to the load information obtained from the drive device; the fuel cell controller adjusts the speed of the fan according to the temperature of the fuel cell stack measured by the temperature sensor.

[0014] Furthermore, the hydrogen delivery pressure of the hydrogen storage tank has a first preset pressure value of 1.2 bar and a second preset pressure value of 0.2 bar. When the pressure value measured by the gas pressure sensor is greater than the first preset pressure value of 1.2 bar or less than the second preset pressure value of 0.2 bar, the fuel cell controller transmits an alarm signal to the vehicle controller and controls the intake solenoid valve to close.

[0015] When the voltage value of the fuel cell stack electrode measured by the inspection line is lower than the preset voltage value, the fuel cell controller sends an alarm signal to the vehicle controller and controls the intake solenoid valve to close.

[0016] Furthermore, the vehicle controller is electrically connected to the drive device, and the vehicle controller controls the operating power of the drive device according to the control signal, and the vehicle controller switches the intervention of the fuel cell stack and the battery according to the load power of the drive device.

[0017] The technical solution provided by the embodiment of the present invention has the following beneficial effects: a low-pressure hydrogen storage tank is used as a hydrogen source to achieve low-pressure, high-density hydrogen storage and high-purity hydrogen supply, which is reusable, safe, economical, and has good adaptability; the waste heat generated during the operation of the fuel cell stack can be utilized to achieve thermal compensation through the designed thermal management airflow channel, thereby effectively improving the hydrogen release performance of the hydrogen storage tank and effectively reducing the energy loss of the entire power system; the stack, hydrogen pipeline, thermal management system and corresponding control system are highly integrated through mechatronics, with a compact structure, and can stably provide stable power for the power system of the power-assisted bicycle to meet actual power requirements such as climbing; the power system of the power-assisted bicycle has low loss, is low-carbon and environmentally friendly, and meets the needs of the economic and social market. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic structural diagram of a power system of an electric bicycle according to an embodiment of the present invention is shown;

[0019] Figure 2 Shows Figure 1 A partial enlarged schematic diagram of part A;

[0020] Figure 3 A schematic structural diagram of a fuel cell device according to an embodiment of the present invention is shown;

[0021] Figure 4 A partial structural schematic diagram of a power system of an electric power-assisted bicycle according to an embodiment of the present invention is shown.

[0022] The symbols in the figure are explained as follows:

[0023] 11 hydrogen storage tank, 12 bottle mouth valve, 13 hydrogen supply pipeline, 14 electric heating element, 15 heat insulation layer, 21 pressure regulating valve, 22 gas pressure sensor, 23 air intake solenoid valve, 24 fuel cell stack, 25 fan, 26 hydrogen inlet, 27 hydrogen outlet, 28 outlet solenoid valve, 29 drain, 31 fuel cell controller, 32 vehicle controller, 33 central control device, 34 battery, 41 air inlet, 42 air outlet, 43 second air flow channel, 44 first air flow channel, 45 exhaust outlet, 50 seat, 102 exhaust hood, 402 front oblique beam, 404 connecting pedal, 406 main vertical pipe, 452 air inlet. DETAILED DESCRIPTION

[0024] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments of the present invention and their beneficial effects will be further described in detail below with reference to the accompanying drawings.

[0025] like Figures 1 to 4 As shown, one embodiment of the present invention provides a power system for an assistive bicycle.

[0026] The power system of the power-assisted bicycle includes a hydrogen storage tank 11, a fuel cell device, a control device and a driving device. The hydrogen storage tank 11 is specifically a solid hydrogen storage alloy tank, which is used to store and provide high-purity hydrogen. The hydrogen storage tank 11 supplies hydrogen to the fuel cell device through a hydrogen supply pipeline 13, and the fuel cell device supplies power to the hydrogen storage tank 11, the driving device and the control device through a power supply line, thereby providing the required electrical energy for the normal operation of the driving device, the control device and the hydrogen storage tank 11.

[0027] The power-assisted bicycle has a frame, which specifically includes: a front oblique beam 402, a connecting pedal 404 and a main vertical pipe 406 connected in sequence, the interior of the main vertical pipe 406 and the interior of the connecting pedal 404 are both hollow, and the interior of the main vertical pipe 406 is connected to the interior of the connecting pedal 404. The hydrogen storage tank 11 is arranged in the main riser 406, and the fuel cell device is arranged in the connecting pedal 404, wherein the main riser 406 is provided with an air inlet 452 and an air outlet 45, so that a first wind flow channel 44 for air flow is formed inside the main riser 406, and the hydrogen storage tank 11 is arranged on the inner wall of the main riser 406, and the air flowing in the first wind flow channel 44 contacts the outer wall of the hydrogen storage tank 11; the fuel cell device specifically includes: a fuel cell stack 24, an exhaust hood 102, and the space inside the exhaust hood 102 is a second wind flow channel 43 for air flow, one end of the exhaust hood 102 is connected to the fuel cell stack 24, and the other end passes through the top wall of the connecting pedal 404 and is connected to the inside of the main riser 406, so that one end of the second wind flow channel 43 is connected to the air outlet of the fuel cell stack 24, and the other end is connected to the air inlet 452 on the main riser 406, and by setting the exhaust The wind hood 102 allows the hot air exhausted from the fuel cell stack 24 to directly enter the first wind channel 44 of the main riser 406, thereby preventing the hot air from flowing into the internal space connected to the pedal 404 and affecting the heat dissipation of the fuel cell stack 24. It should be noted that the hot air exhausted from the fuel cell stack 24 passes through the second wind channel 43 and the first wind channel 44, flows through the hydrogen storage tank 11, and is discharged from the exhaust port 45 arranged on the main riser 406. Specifically, the air exhausted from the air outlet of the fuel cell stack 24 is the gas generated by the reaction between the air and hydrogen in the fuel cell device. The air enters the positive electrode of the fuel cell stack 24 and reacts with the hydrogen on the negative electrode of the fuel cell stack 24 to generate electricity and a large amount of heat. The gas generated after the reaction takes out the heat from the air outlet of the fuel cell device, thereby forming hot air. The hot air passes through the second wind channel 43 and the air inlet 452 Then it flows into the first air flow channel 44. When flowing through the hydrogen storage tank 11, the hot air exchanges heat with the hydrogen storage tank 11, providing part of the heat for the hydrogen storage tank 11, so as to facilitate the sustainable release of hydrogen by the hydrogen storage tank 11. After the hot air exchanges heat with the hydrogen storage tank 11, it is discharged through the exhaust port 45, and the exhaust port 45 is the final outlet of the entire power system.

[0028] Among them, the fuel cell device is arranged in the connecting pedal 404, which is beneficial to lowering the center of gravity of the power-assisted bicycle and improving the driving stability of the power-assisted bicycle. The hydrogen storage tank 11 is arranged in the main vertical pipe 406, so that the height of the hydrogen storage tank 11 is higher than the fuel cell device. Therefore, the hot air discharged from the air outlet of the fuel cell device flows from low to high, making the flow of hot air smoother. In addition, the fuel cell stack 24 and the hydrogen storage tank 11 are close to the middle position of the power-assisted bicycle, so that the center of gravity of the whole vehicle is also close to the middle, which is beneficial to improving the controllability of the power-assisted bicycle.

[0029] The fuel cell stack 24 is an air-cooled proton exchange membrane fuel cell stack, and its power is between 100W and 500W.

[0030] Among them, along the direction from the air outlet of the fuel cell stack 24 to the air inlet 452 of the main riser 406, the cross-sectional area of ​​the second air duct 43 gradually decreases, and the inner wall of the exhaust hood 102 transitions smoothly to reduce the wind resistance coefficient of the second air duct 43 and make the air flow smoother.

[0031] It should be emphasized that the hot air exhausted from the fuel cell device passes through the second air flow channel 43 and enters the first air flow channel 44 to supply heat for the hydrogen storage tank 11 to release hydrogen, effectively utilizing waste heat, achieving energy complementarity, and reducing system losses.

[0032] Furthermore, the air inlet 452 is arranged at the bottom of the main riser 406, and the air outlet 45 is arranged at the top of the main riser 406. After the hot air enters the first air flow channel 44 from the air inlet 452 at the bottom of the main riser 406, it is discharged from the air outlet 45 at the top of the main riser 406 to increase the contact time between the hot air and the hydrogen storage tank 11 and improve the utilization rate of the heat of the hot air.

[0033] When a fuel cell device is running, the supply of hydrogen is a relatively important link. The characteristics of solid-state hydrogen storage technology are safety, simplicity, good adaptability, and can solve the hydrogen storage problem well. It can provide a stable and reliable hydrogen source for fuel cell devices. Among them, metal hydride (MH) has great application prospects as a carrier of solid-state hydrogen storage in fuel cells. Metal hydride (MH), including AB 5 Type, AB 2 Type, AB type, BCC type, etc., not only have extremely high volume hydrogen storage density (100g L -1 Even higher), and at a suitable temperature, the low equilibrium hydrogen pressure and the endothermic nature of the metal hydride dehydrogenation reaction together lead to the high safety of the metal hydride-based hydrogen storage system. The metal hydride dehydrogenation reaction has the characteristic of endothermicity, with AB 5 (LaNi 5 ) as an example, its reaction enthalpy is -27kJ / mol H 2 The heat required to release hydrogen accounts for about 1 / 4 of the electricity generated by the fuel cell.

[0034] Since the dehydrogenation of the hydrogen storage alloy is an endothermic process, it needs to absorb a large amount of heat from the outside. Therefore, the power system of the power-assisted bicycle is also provided with an electric heating element 14, which is coated on the outer surface of the hydrogen storage tank 11; the electric heating element 14 is electrically connected to the control device, so that the fuel cell device supplies electric energy to the electric heating element 14 through the control device, so that the electric heating element 14 generates heat to heat the hydrogen storage tank 11, and provide heat for the dehydrogenation reaction of the metal hydride in the hydrogen storage tank 11, so as to ensure the heat required for the dehydrogenation of the hydrogen storage alloy; it should be noted that the electric heating element 14 can quickly change its own temperature and quickly provide the required heat for the hydrogen storage tank 11. When the hydrogen fuel cell is applied to the electric bicycle, the hydrogen fuel cell needs to continuously supply power to the driving device of the electric bicycle, and the hydrogen storage tank 11 in the hydrogen fuel cell system (i.e., the fuel cell device) continuously absorbs heat. Therefore, the electric heating element 14 can heat the hydrogen storage tank 11 in the hydrogen fuel cell system, that is, it can ensure the continuous operation of the hydrogen fuel cell power-assisted bicycle, which solves the problem of the hydrogen storage tank 11 in the current hydrogen fuel cell power-assisted bicycle continuously absorbing heat.

[0035] Optionally, the electric heating element 14 is in sheet form and is attached to the outer wall of the hydrogen storage tank 11 .

[0036] Optionally, the electric heating element 14 is in a strip shape and is wound around the outer wall of the hydrogen storage tank 11 .

[0037] Furthermore, the control device adjusts the heating power of the electric heating element 14 according to the output power of the driving device. Specifically, when the output power of the driving device is greater, it means that the amount of hydrogen that the fuel cell device needs to consume is greater, and the amount of hydrogen released by the hydrogen storage tank 11 is greater, and the more heat is absorbed by the metal hydride dehydrogenation reaction. Therefore, the control device controls the electric heating element 14 to increase the heating power to provide more heat to meet the demand for heat absorbed by the metal hydride dehydrogenation reaction. It should be emphasized that adjusting the heating power of the electric heating element 14 can quickly change the temperature of the electric heating element 14, so that the electric heating element 14 can quickly adjust the heat provided to the hydrogen storage tank 11 according to the different hydrogen requirements of the fuel cell device, so as to accurately control the amount of hydrogen released by the hydrogen storage tank 11, and avoid insufficient power supply to the fuel cell device due to the mismatch between the amount of hydrogen required by the fuel cell device and the hydrogen supply of the hydrogen storage tank 11.

[0038] Optionally, the material contained in the low-pressure hydrogen storage tank 11 is AB, AB 2 , A 2 B.AB 5Or BCC type solid hydrogen storage alloy material and auxiliary ingredients, specifically, the auxiliary ingredients include graphite, copper powder, aluminum powder, etc.; the hydrogen storage tank 11 is an aluminum alloy gas cylinder, the volume of the aluminum alloy gas cylinder is not too limited, and it is best not to exceed 2L due to the influence of the bicycle space. The volume of the aluminum alloy gas cylinder is preferably 0.5L~1L, and the release flow rate of hydrogen in the hydrogen storage tank 11 is generally 0.1L / min~10L / min. In this application, the release flow rate of hydrogen is related to the power of the fuel cell stack 24. The fuel cell stack 24 of the power-assisted bicycle generally does not exceed 500w, and the hydrogen flow rate in the hydrogen storage tank 11 should not exceed 6L / min accordingly.

[0039] The pressure of the hydrogen storage tank 11 during operation is 0.5 bar to 3 bar.

[0040] Optionally, the electric heating element 14 is any one or more of a polyimide film heating belt, a silicone rubber heating belt, a glass fiber heating belt, a ceramic heating belt, a graphene heating plate, a carbon crystal heating plate or an aluminum foil heating plate; the electric heating element 14 is connected to the fuel cell controller 31 in the control device, and the power required by the electric heating element 14 comes from the electricity generated by the fuel cell device, and the heating power is 20W to 50W.

[0041] like Figure 1 As shown, further, the power system of the power-assisted bicycle also includes: a heat insulation layer 15, which is arranged between the hydrogen storage tank 11 and the inner wall of the main vertical pipe 406, and the heat insulation layer 15 is used to isolate heat conduction. The hydrogen storage tank 11 is arranged on the inner wall of one side of the main vertical pipe 406, and the heat insulation layer 15 is laid between the electric heating element 14 on the outer wall of the hydrogen storage tank 11 and the inner wall of one side of the main vertical pipe 406 to prevent the heat of the electric heating element 14 from being diffused and lost through the aluminum alloy frame. The space between the inner wall on the other side of the main vertical pipe 406 and the hydrogen storage tank 11 is the first air flow channel 44.

[0042] like Figure 3As shown, the fuel cell device specifically further includes: a fan 25; an air inlet 41 and an air outlet 42 are respectively provided on two opposite surfaces of the fuel cell stack 24, and the air outlet 42 is the air outlet of the fuel cell stack 24; the fan 25 is provided on the air outlet 42, and two or more fans 25 can be provided. The air outlet of the fan 25 is provided in the second air flow channel 43. Driven by the fan 25, the outside air is sucked into the fuel cell stack 24 from the air inlet 41 of the fuel cell stack 24, and the fuel cell stack 24 is provided with oxygen required for the reaction. A hydrogen inlet 26 is provided on the upper part of one side of the fuel cell stack 24, and the hydrogen provided by the hydrogen storage tank 11 enters the negative electrode of the fuel cell stack 24 from the hydrogen inlet 26, so that the oxygen at the positive electrode of the fuel cell stack 24 reacts with the hydrogen at the negative electrode of the fuel cell stack 24 to generate electricity, and part of the electric energy is supplied to the output of the drive device and the fuel cell controller 31, and part of the electric energy is supplied to the fuel cell controller 31. Electric energy is provided to the electric heating element 14 for heating and then providing heat to the hydrogen storage tank 11; the hydrogen in the fuel cell stack 24 reacts with oxygen and generates a large amount of heat at the same time, and the fan 25 takes out the heat through the air outlet 42 of the fuel cell stack 24, and guides it upward along the second wind channel 43 to the first wind channel 44, and the hot air blows from the bottom of the hydrogen storage tank 11 along the first wind channel 44 to the top of the hydrogen storage tank 11, providing part of the heat for the hydrogen storage tank 11, and the hot air is discharged from the exhaust port 45 above, in this process, the fuel cell stack 24 is cooled, and heat is provided for the hydrogen storage alloy to release hydrogen, realizing energy complementarity. The heat provided by the hot air to the hydrogen storage tank 11 further ensures the continuous operation of the power-assisted bicycle, and together with the electric heating element 14, solves the problem of the hydrogen storage tank 11 in the current hydrogen fuel cell power-assisted bicycle continuously absorbing heat.

[0043] A hydrogen outlet 27 is provided at the lower part of one side of the fuel cell stack 24, and an outlet solenoid valve 28 is provided on the hydrogen outlet 27. A drain port 29 is provided at the bottom where a connecting pedal 404 is provided. The remaining reaction gas and water generated by the reaction pass through the hydrogen outlet 27 and the outlet solenoid valve 28 and are discharged from the connecting pedal 404 through the drain port 29.

[0044] like Figure 1As shown, further, a bottle mouth valve 12 is provided on the bottle mouth of the hydrogen storage tank 11, the first end of the hydrogen supply pipeline 13 is connected to the hydrogen storage tank 11 through the bottle mouth valve 12, and the second end of the hydrogen supply pipeline 13 is connected to the hydrogen inlet 26, and a pressure-stabilizing valve 21, a gas pressure sensor 22, and an intake solenoid valve 23 are sequentially provided on the hydrogen supply pipeline 13 from the first end to the second end, wherein the bottle mouth valve 12 is used to control the on and off of the hydrogen in the hydrogen storage tank 11, and the pressure-stabilizing valve 21 is used to stabilize the pressure of the hydrogen transported, so that the hydrogen transport pressure of the hydrogen storage tank 11 is stabilized at the hydrogen use pressure of the fuel cell stack 24 of 0.4 to 0.5 bar; the gas pressure sensor 22 is between the pressure-stabilizing valve 21 and the intake solenoid valve 23, and is used to detect the outlet pressure of the hydrogen storage tank 11. After the hydrogen in the hydrogen storage tank 11 is consumed, the gas pressure decreases and the fuel cell device needs to be shut down. The main function of the intake solenoid valve 23 is to determine the start and shutdown of the fuel cell stack 24 through the control of the control device. After the intake solenoid valve 23 is opened, hydrogen is released through the hydrogen storage tank 11, enters the hydrogen supply pipeline 13 through the bottle mouth valve 12, and enters the fuel cell stack 24 through the pressure regulating valve 21, the gas pressure sensor 22 and the intake solenoid valve 23. Hydrogen enters the fuel cell stack 24 as a reducing agent for power generation.

[0045] Furthermore, the control device specifically includes: a fuel cell controller 31, a vehicle controller 32, a battery 34, a central control device 33 and a display screen which are electrically connected to each other, wherein the display screen is arranged in the middle position of the bicycle handlebar; the fuel cell controller 31, the vehicle controller 32, and the battery 34 are arranged in the connecting pedal 404, and the central control device 33 is arranged in the seat 50 at the top of the main riser 406, and the battery 34 provides starting power for the fuel cell controller 31 and the vehicle controller 32, so as to realize one-button starting of the entire power-assisted bicycle.

[0046] The power system of the power-assisted bicycle also includes: a vehicle lock, which is electrically connected to the central control device 33; the display screen obtains unlocking or locking information and transmits it to the central control device 33, the central control device 33 controls the vehicle lock to be opened according to the obtained unlocking information, or the central control device 33 controls the vehicle lock to be closed according to the obtained locking information, wherein the unlocking or locking information obtained by the display screen can be obtained through interactive information with the smart device, such as the display screen produces a QR code, after the smart device obtains the QR code information, it identifies the QR code, and sends corresponding unlocking or locking information to the central control device 33 according to the QR code information, the central control device 33 controls the vehicle lock to be opened according to the obtained unlocking information, or the central control device 33 controls the vehicle lock to be closed according to the obtained locking information, thereby realizing functions such as scanning the code to unlock and lock the power-assisted bicycle.

[0047] Optionally, the battery 34 is composed of any one of a lithium-ion battery pack, a nickel-metal hydride battery pack, or a lead-acid battery.

[0048] Furthermore, the central control device 33 includes a main control module and a GPRS module; the main control module is electrically connected to the gas pressure sensor 22, the drive device, the GPRS module and the display screen to collect the gas pressure of the hydrogen storage tank 11 (the data of the gas pressure sensor 22), the current and voltage of the drive device and transmit them to the display screen for display, so as to assist the bicycle in realizing functions such as scanning the code to unlock and lock. The GPRS module is used for vehicle positioning and networking, and the alarm information is sent to the system background through the GPRS module to remind the operation and maintenance personnel to replace the hydrogen storage tank 11 according to the hydrogen storage amount.

[0049] Furthermore, if Figure 2 As shown, the power system of the fuel cell assisted bicycle also includes: a temperature sensor arranged on the fuel cell stack 24, and a patrol line electrically connected to the stack electrode of the fuel cell stack 24 and the fuel cell controller 31, the fuel cell controller 31 is electrically connected to the drive device, the gas pressure sensor 22, the air intake solenoid valve 23, the fan 25, the temperature sensor, the patrol line and the air outlet solenoid valve 28; wherein the fuel cell controller 31 controls the on and off of the air intake solenoid valve 23 and the air outlet solenoid valve 28, as well as the switch of the electric heating element 14. The fuel cell controller 31 monitors the air pressure after the pressure regulating valve 21 is reduced by the gas pressure sensor 22. The hydrogen delivery pressure of the hydrogen storage tank 11 has a first preset air pressure value of 1.2 bar and a second preset air pressure value of 0.2 bar. When the air pressure value measured by the gas pressure sensor 22 is greater than the first preset air pressure value (1.2 bar) or less than the second preset air pressure value (0.2 bar), the fuel cell controller 31 sends an alarm signal to the vehicle controller 32 and controls the closing of the air intake solenoid valve 23 to protect the fuel cell stack 24. Too high or too low pressure will damage the fuel cell stack 24. At the same time, the low pressure alarm will also prompt that the hydrogen in the hydrogen storage tank is about to be consumed. After the air outlet solenoid valve 28 is opened for 2s, the air outlet solenoid valve 28 and the fan 25 are closed, thereby shutting down the entire fuel cell device to protect the fuel cell device. At the same time, it also serves to prompt that the hydrogen in the hydrogen storage tank 11 has been consumed.

[0050] The fuel cell controller 31 monitors the temperature of the fuel cell stack 24 in real time through a temperature sensor. When the temperature is higher than a set value (60° C.), a high temperature alarm is issued and the fuel cell device is shut down.

[0051] The fuel cell controller 31 monitors the voltage of the stack pole pieces of the fuel cell stack 24 through the inspection line. When the voltage value of the stack pole pieces of the fuel cell stack 24 measured by the inspection line is lower than the preset voltage value of 0.4V, the fuel cell controller 31 sends an alarm signal to the vehicle controller 32 and controls the intake solenoid valve 23 to close, thereby shutting down the fuel cell device.

[0052] The fuel cell controller 31 controls the speed of the fan 25 according to the obtained temperature of the fuel cell stack 24 . Specifically, the speed of the fan 25 is proportional to the temperature of the fuel cell stack 24 , so that the temperature of the fuel cell stack 24 is maintained within a normal range, ensuring the normal operation of the fuel cell stack 24 .

[0053] The vehicle controller 32 is electrically connected to the drive device. The vehicle controller 32 controls the operating power of the drive device according to a control signal. The control signal is a control signal input by the user, such as acceleration, deceleration, braking and other signals. The drive device is specifically a motor. For example, when the user inputs an acceleration signal, the vehicle controller 32 controls to increase the operating power of the motor, thereby increasing the operating speed of the power system of the power-assisted bicycle; further, the vehicle controller 32 switches the intervention of the fuel cell stack 24 and the battery 34 according to the load power of the drive device. In detail, if the operating power required by the motor is greater than the rated power of the fuel cell device, the vehicle controller 32 controls the battery 34 and the fuel cell device to power the motor at the same time to meet the power demand of the motor.

[0054] The working principle of the power system of the power-assisted bicycle is as follows:

[0055] The solid-state hydrogen storage tank 11 provides hydrogen, and the battery 34 serves as the starting power supply for the fuel cell device. When the start button of the power-assisted bicycle is clicked, the fuel cell controller 31 starts working, opens the air intake solenoid valve 23 and the fan 25, and the fuel cell stack 24 starts working. When the fuel cell controller 31 detects the motor input signal, it opens the air intake solenoid valve 23, and opens the air outlet solenoid valve 28 at a certain interval (2s) to discharge the water produced by the reaction of the fuel cell stack 24. According to the actual motor output power demand, the fuel cell stack 24 can output the corresponding power; at the same time, the fuel cell controller 31 also controls the speed of the fan 25, and adjusts the speed of the fan 25 according to the temperature of the fuel cell stack 24 to ensure that the fuel cell stack 24 maintains a suitable working temperature; the fuel cell controller 31 also monitors the temperature of the fuel cell stack 24 in real time through the temperature sensor. When the temperature is higher than the set value, the fuel cell controller 31 A high temperature alarm is issued and the fuel cell stack 24 is shut down; the fuel cell controller 31 monitors the gas pressure in the hydrogen supply pipeline 13 after the pressure regulating valve 21 is reduced through the gas pressure sensor 22. When the hydrogen in the hydrogen storage tank 11 is consumed by 90%, that is, the remaining hydrogen in the hydrogen storage tank 11 is less than 10%, and the gas pressure is lower than the set value, a low pressure alarm is issued, the fuel cell stack 24 is shut down, and the operation and maintenance personnel are reminded to replace the hydrogen storage tank 11 according to the hydrogen storage amount; the fuel cell controller 31 monitors the voltage of the stack electrode of the fuel cell stack 24. When the voltage is lower than the set value, a low voltage alarm is issued and the fuel cell stack 24 is shut down; the waste heat generated by the operation of the fuel cell stack 24 passes through the air outlet 42 of the fuel cell stack 24, along the wind flow path (that is, the second wind flow path 43) of the fuel cell device, enters the wind flow path (that is, the first wind flow path 44) of the hydrogen storage tank 11, provides heat for the solid alloy hydrogen storage tank 11, and also cools down the entire fuel cell device, effectively utilizes the waste heat, realizes energy complementarity, and reduces system losses.

[0056] The beneficial effects of the present invention are as follows:

[0057] 1. The low-pressure hydrogen storage tank 11 is used as the hydrogen source, which can realize low-pressure high-density hydrogen storage and high-purity hydrogen supply, is reusable, safe, economical, and has good adaptability;

[0058] 2. It can utilize the waste heat generated by the fuel cell stack 24 during operation, realize heat compensation through the designed thermal management air flow channel, effectively improve the hydrogen release performance of the hydrogen storage tank 11, and effectively reduce the energy loss of the entire power system;

[0059] 3. The fuel cell stack 24, the hydrogen supply pipeline 13, the thermal management system and the corresponding control system are highly integrated through mechatronics, and the structure is compact, which can provide stable power for the power system of the power-assisted bicycle and meet the actual power requirements such as climbing a hill;

[0060] 4. The power system of hydrogen fuel cell-assisted bicycles has low loss, is low-carbon and environmentally friendly, and meets the needs of the economic and social markets.

[0061] In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0062] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front” and “back” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0063] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0064] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A power system for a power-assisted bicycle, characterized in that: The power system comprises a hydrogen storage tank, a fuel cell device, a control device and a drive device, wherein the hydrogen storage tank supplies hydrogen to the fuel cell device through a hydrogen supply pipeline, and the fuel cell device supplies electric energy to the hydrogen storage tank, the drive device and the control device respectively through a power supply line; The power-assisted bicycle has a frame, which specifically includes: a front oblique beam, a connecting pedal and a main vertical pipe connected in sequence, the main vertical pipe and the connecting pedal are hollow inside, the main vertical pipe is provided with an air inlet and an air outlet, so that a first air flow channel is formed inside the main vertical pipe, and the hydrogen storage tank is arranged on the inner wall of the main vertical pipe; The fuel cell device specifically comprises: a fuel cell stack and an exhaust hood, wherein the fuel cell stack is arranged in the connecting pedal, and a second air flow passage for air flow is arranged in the exhaust hood, one end of the exhaust hood is connected to the fuel cell stack, and the other end of the exhaust hood passes through the top wall of the connecting pedal and communicates with the interior of the main riser, so that one end of the second air flow passage is communicated with the air outlet of the fuel cell stack, and the other end is communicated with the air inlet on the main riser; The hot air discharged from the fuel cell stack enters the first air flow channel through the second air flow channel, flows through the outer surface of the hydrogen storage tank, and is discharged from the exhaust port. The air inlet is arranged at the bottom of the main riser, and the air outlet is arranged at the top of the main riser; Along the direction from the air outlet of the fuel cell stack to the air inlet of the main riser, the cross-sectional area of ​​the second air flow channel gradually decreases, and the inner wall of the exhaust hood has a smooth transition, and further comprising: An electric heating element, coated on the outer surface of the hydrogen storage tank; A heat insulation layer is provided between the hydrogen storage tank and the inner wall of the main riser; The electric heating element is electrically connected to the control device, and the fuel cell device supplies power to the electric heating element through the control device; The fuel cell device further comprises: A fan is provided at the air outlet of the fuel cell stack; An air inlet and an air outlet are respectively provided on two opposite surfaces of the fuel cell stack; the air outlet of the fan is connected to a second air flow channel, and air flows from the air outlet into the second air flow channel under the drive of the fan; A hydrogen inlet and a hydrogen outlet are respectively provided at the lower and upper parts of one side of the fuel cell stack, and a gas outlet solenoid valve is provided on the hydrogen outlet. A drain outlet is provided at the bottom of the connecting pedal, and the gas and water discharged from the hydrogen outlet are discharged through the drain outlet.

2. The power system of the power-assisted bicycle according to claim 1, characterized in that: The electric heating element is a belt-shaped heating belt; or the electric heating element is a sheet-shaped heating sheet.

3. The power system of the power-assisted bicycle according to claim 1, characterized in that: A bottle mouth valve is provided on the bottle mouth of the hydrogen storage tank, a first end of the hydrogen supply pipeline is connected to the hydrogen storage tank through the bottle mouth valve, and a second end is connected to the hydrogen inlet port, and a pressure stabilizing valve, a gas pressure sensor, and an air intake solenoid valve are sequentially provided on the hydrogen supply pipeline from the first end to the second end; The power system of the power-assisted bicycle also has a seat, which is arranged at the top end of the main stand pipe. The control device specifically includes: a fuel cell controller, a vehicle controller, a storage battery, a central control device, and a display screen electrically connected to each other; The fuel cell controller, the vehicle controller, and the battery are arranged in the connecting pedal, the central control device is arranged in the vehicle seat, and the battery provides starting power for the fuel cell controller and the vehicle controller.

4. The power system of the power-assisted bicycle according to claim 3, characterized in that: Also includes: A vehicle lock, electrically connected to the central control device; The display screen acquires unlocking or locking information and transmits it to the central control device, and the central control device controls the vehicle lock to be opened according to the unlocking information obtained, or the central control device controls the vehicle lock to be closed according to the locking information obtained.

5. The power system of the power-assisted bicycle according to claim 4, characterized in that: The central control device includes a main control module and a GPRS module; The main control module is electrically connected to the gas pressure sensor, the drive device, the GPRS module and the display screen to respectively collect data such as the gas pressure of the hydrogen storage tank, the current and voltage of the drive device and transmit them to the display screen for display. The GPRS module is used for vehicle positioning and networking, and the alarm information is sent to the system background through the GPRS module.

6. The power system of the power-assisted bicycle according to claim 4, characterized in that: Also includes: A temperature sensor provided on the fuel cell stack, a patrol line electrically connected to the stack electrode of the fuel cell stack and the fuel cell controller, and the fuel cell controller is electrically connected to the drive device, the gas pressure sensor, the air inlet solenoid valve, the fan, the temperature sensor, the patrol line and the air outlet solenoid valve; Wherein, the fuel cell controller controls the opening or closing of the air inlet solenoid valve and the air outlet solenoid valve according to the data information obtained from the gas pressure sensor, the temperature sensor and the inspection line; The fuel cell controller controls the heating power of the electric heating element according to the acquired load information of the driving device; The fuel cell controller adjusts the speed of the fan according to the temperature of the fuel cell stack measured by the temperature sensor.

7. The power system of the power-assisted bicycle according to claim 6, characterized in that: The hydrogen delivery pressure of the hydrogen storage tank has a first preset pressure value of 1.2 bar and a second preset pressure value of 0.2 bar. When the pressure value measured by the gas pressure sensor is greater than the first preset pressure value or less than the second preset pressure value, the fuel cell controller transmits an alarm signal to the vehicle controller and controls the intake solenoid valve to close; When the voltage value of the stack electrode of the fuel cell stack measured by the inspection line is lower than a preset voltage value, the fuel cell controller transmits an alarm signal to the vehicle controller and controls the air intake solenoid valve to close.

8. The power system of the power-assisted bicycle according to claim 4, characterized in that: The vehicle controller is electrically connected to the drive device, and controls the operating power of the drive device according to a control signal. The vehicle controller switches the intervention of the fuel cell stack and the battery according to the load power of the drive device.

Images