Power system of battery-assisted bicycle

Abstract

The present invention provides a power system of a battery-assisted bicycle, including a hydrogen storage tank, a fuel cell stack, a control device, a driving device, and a frame. The frame includes: a front oblique beam, a connecting pedal, and a main vertical pipe. The two ends of the connecting pedal are respectively connected to the lower end of the front oblique beam and the lower end of the main vertical pipe. The interior of the front oblique beam and the interior of the main vertical pipe are hollow, and an exhaust passage connecting the internal space of the front oblique beam and the internal space of the main vertical pipe is provided in the connecting pedal. The top of the main vertical pipe is provided with an exhaust port. The fuel cell stack is arranged in the front oblique beam, and the hydrogen storage tank is arranged in the main vertical pipe. The hot air discharged from the fuel cell stack enters the main vertical pipe through the exhaust passage, 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 electric bicycles, hydrogen storage technologies and fuel cell technologies, and in particular to a power system of a battery-assisted bicycle. Background Art

[0002] Hydrogen energy is considered to be an ideal clean energy with advantages such as 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 large amount 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 hazards. In addition, due to technical limitations, the cost of domestic liquid hydrogen application is very high. In the context of advocating energy conservation, emission reduction and low-carbon travel, public transportation such as bicycles, buses, subways, and light rail are undoubtedly people's preferred means of travel. Among them, bicycles have an irreplaceable special status in the existing public transportation system, playing a role in connecting destinations with subway stations and bus stops. Hydrogen-powered bicycles that use low-pressure solid-state hydrogen storage as a hydrogen source have become an ideal choice for green, low-carbon, safe and environmentally friendly travel in the economic and social fields. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0004] In view of this, one object of the present invention is to provide a power system for a battery-assisted bicycle.

[0005] In order to achieve the above-mentioned purpose, the technical solution of the present invention provides a battery-assisted bicycle, the power system of which includes: a hydrogen storage tank, a fuel cell stack, a control device and a drive device, the hydrogen storage tank supplies hydrogen to the fuel cell stack through a hydrogen supply pipeline, and the fuel cell stack supplies electric energy to the hydrogen storage tank, the drive device and the control device respectively through a power supply line, characterized in that the power-assisted bicycle has a frame, the frame includes: a front oblique beam, a connecting pedal, and a main vertical pipe, the two ends of the connecting pedal are respectively connected to the lower end of the front oblique beam and the lower end of the main vertical pipe, the interior of the front oblique beam and the interior of the main vertical pipe are both hollow, and an exhaust passage connecting the internal space of the front oblique beam and the internal space of the main vertical pipe is provided in the connecting pedal, and an exhaust port is provided on the top of the main vertical pipe; the fuel cell stack is arranged in the front oblique beam, the hydrogen storage tank is arranged in the main vertical pipe, and the hot air exhausted by the fuel cell stack enters the main vertical pipe through the exhaust passage, and is discharged from the exhaust port after flowing through the outer surface of the hydrogen storage tank.

[0006] Furthermore, an air inlet is provided on the lower side wall of the front oblique beam, and the air inlet of the fuel cell stack is connected to the air inlet; a fan is provided on the air outlet of the fuel cell stack; an electric heating element is 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 stack supplies power to the electric heating element through the control device; the air inlet and the air outlet are respectively provided on two opposite sides of the fuel cell stack; a hydrogen outlet and a hydrogen inlet are respectively provided on the lower part and the upper part of one side of the fuel cell stack, and an outlet solenoid valve is provided on the hydrogen outlet; the fuel cell controller controls the heating power of the electric heating element according to the load information of the driving device obtained; preferably, the electric heating element is a belt-shaped heating belt; or the electric heating element is a sheet-shaped heating sheet;

[0007] Furthermore, a foot platform extending in the horizontal direction is provided on the top of the connecting pedal, and a drain port connecting the exhaust passage and the outside atmosphere is provided on the bottom of the connecting pedal, and water discharged from the hydrogen outlet is discharged through the drain port.

[0008] 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 sequentially provided on the hydrogen supply pipeline from the first end to the second end.

[0009] Furthermore, the power-assisted bicycle also has a seat, which is arranged at the top of the main vertical tube. 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 main vertical tube, the central control device is arranged in the seat, and the battery provides starting power for the fuel cell controller and the vehicle controller.

[0010] Furthermore, it also includes: a car 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 car lock to open according to the unlocking information obtained, or the central control device controls the car lock to close according to the locking information obtained.

[0011] 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.

[0012] Furthermore, it also includes: a temperature sensor arranged on the fuel cell stack, a patrol line electrically connected to the stack electrode of the fuel cell stack and the fuel cell controller, 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; 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 adjusts the speed of the fan according to the temperature of the fuel cell stack measured by the temperature sensor.

[0013] 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 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 fuel cell stack electrode measured by the inspection line is lower than the preset voltage value, the fuel cell controller transmits an alarm signal to the vehicle controller and controls the intake solenoid valve to close.

[0014] 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.

[0015] 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, so as to realize 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, and thermal compensation can be realized through the designed thermal management airflow channel, so as to effectively improve the hydrogen release performance of the hydrogen storage tank and effectively reduce 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-assisted bicycle to meet the actual power requirements such as climbing hills; the power system of the battery-assisted bicycle has low loss, is low-carbon and environmentally friendly, and meets the economic and social market needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic structural diagram of a power system of a battery-assisted bicycle according to an embodiment of the present invention is shown;

[0017] Figure 2 A schematic diagram showing the structure of a fuel cell stack and a fan according to an embodiment of the present invention is shown;

[0018] Figure 3 Shows Figure 1 A partial enlarged schematic diagram of part A.

[0019] The symbols in the figure are explained as follows:

[0020] 11 hydrogen storage tank, 12 bottle mouth valve, 13 hydrogen supply pipeline, 14 electric heating element, 15 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 air outlet solenoid valve, 29 drain outlet, 31 fuel cell controller, 32 vehicle controller, 33 central control device, 34 battery, 41 air inlet, 42 air outlet, 44 exhaust duct, 45 exhaust outlet, 50 seat, 402 front oblique beam, 404 connecting pedal, 406 main riser, 408 foot platform, 412 rear bracket, 452 air inlet. DETAILED DESCRIPTION

[0021] 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.

[0022] like Figures 1 to 3 As shown, one embodiment of the present invention provides a power system for a battery-assisted bicycle.

[0023] The power system includes a hydrogen storage tank 11, a fuel cell stack 24, 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 stack 24 through a hydrogen supply pipeline 13, and the fuel cell stack 24 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.

[0024] The power-assisted bicycle has a frame, which specifically includes: a front oblique beam 402, a connecting pedal 404, a main vertical pipe 406 and a rear bracket 412. The two ends of the connecting pedal 404 are respectively connected to the lower end of the front oblique beam 402 and the lower end of the main vertical pipe 406, and the rear bracket 412 is connected to the main vertical pipe 406. The front oblique beam 402 and the main vertical pipe 406 are both hollow inside, and the connecting pedal 404 is provided with an exhaust passage 44 connecting the interior of the front oblique beam 402 and the interior space of the main vertical pipe 406. The air inside the front oblique beam 402 can enter the main vertical pipe 406 through the exhaust passage 44. 06 and is discharged from the exhaust port 45 arranged at the top of the main riser 406. The fuel cell stack 24 is arranged in the front oblique beam 402, and the hydrogen storage tank 11 is arranged in the main riser 406. The hot air discharged from the fuel cell stack 24 enters the main riser 406 through the exhaust channel 44, and is discharged from the exhaust port 45 after flowing through the outer surface of the hydrogen storage tank 11. When the hot air flows 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 from the hydrogen storage tank 11. Among them, the exhaust port 45 is the final air outlet of the entire power system.

[0025] Furthermore, an air inlet 452 is provided on the lower side wall of the front oblique beam 402, and the air inlet 41 of the fuel cell stack 24 is connected to the air inlet 452. A fan 25 is provided on the air outlet 42 of the fuel cell stack 24, and two or more fans 25 can be provided. When the fan 25 is in operation, the air in the fuel cell stack 24 is driven to be discharged from the air outlet 42, so that the outside air is sucked into the fuel cell stack 24 through the air inlet 452 on the front oblique beam 402 and the air inlet 41 of the fuel cell stack 24, and oxygen is supplied to the positive electrode of the fuel cell stack 24. The oxygen at the positive electrode of the fuel cell stack 24 reacts with the hydrogen on the negative electrode of the fuel cell stack 24 to generate water, generate electricity, and generate a large amount of heat at the same time. The gas after the reaction takes out the heat from the air outlet 42 of the fuel cell stack 24, thereby forming hot air. The hot air flows into the main vertical pipe 406 through the exhaust channel 44 under the drive of the fan 25, and is discharged from the exhaust port 45 after flowing through the hydrogen storage tank 11.

[0026] The fuel cell stack 24 is an air-cooled proton exchange membrane fuel cell stack, and its power is between 100W and 500W.

[0027] It should be emphasized that the hot air exhausted from the fuel cell stack 24 supplies heat to the hydrogen storage tank 11 to release hydrogen, thereby effectively utilizing waste heat, achieving energy complementarity, and reducing system losses.

[0028] Solid-state hydrogen storage technology is characterized by safety, simplicity, good adaptability, and the ability to solve the hydrogen storage problem and provide a stable and reliable hydrogen source for the fuel cell stack 24. Metal hydride (MH) has great application prospects as a carrier for solid-state hydrogen storage in fuel cells. Metal hydride (MH), including AB5 type, AB2 type, AB type, BCC type, etc., not only has an extremely high volume hydrogen storage density (100g L -1 Even higher), and at the right temperature, the lower 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. Metal hydride dehydrogenation reaction has the characteristic of endothermicity. Taking AB5 (LaNi5) as an example, its reaction enthalpy is -27kJ / mol H2, and the heat required for dehydrogenation accounts for about 1 / 4 of the electricity generated by the fuel cell.

[0029] 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 battery-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 stack 24 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 battery-assisted bicycle, and solve the problem of the hydrogen storage tank 11 in the current battery-assisted bicycle continuously absorbing heat.

[0030] Optionally, the electric heating element 14 is in sheet form and is attached to the outer wall of the hydrogen storage tank 11 .

[0031] Optionally, the electric heating element 14 is in a strip shape and is wound around the outer wall of the hydrogen storage tank 11 .

[0032] 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 stack 24 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 stack 24, 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 stack 24 due to the mismatch between the amount of hydrogen required by the fuel cell stack 24 and the hydrogen supply of the hydrogen storage tank 11.

[0033] Optionally, the material of the low-pressure hydrogen storage tank 11 is AB, AB2, A2B, AB5 or 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. Due to the influence of the bicycle space, it is best not to exceed 2L. The volume of the aluminum alloy gas cylinder is preferably 0.5L~1L. 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.

[0034] The pressure of the hydrogen storage tank 11 during operation is 0.5 bar to 3 bar.

[0035] 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 stack 24, and the heating power is 20W to 50W.

[0036] like Figure 1 As shown, further, the battery-assisted bicycle also includes: a heat insulation layer 15, the hydrogen storage tank 11 is arranged on the inner wall of one side of the front oblique beam 402, the heat insulation layer 15 is arranged between the hydrogen storage tank 11 and the inner wall of one side of the front oblique beam 402, the heat insulation layer 15 is used to isolate heat conduction, and is laid between the part where the heating belt contacts the frame to prevent the heat of the electric heating element 14 from diffusing and losing through the aluminum alloy frame.

[0037] like Figure 1 and Figure 2As shown, an air inlet 41 and an air outlet 42 are respectively provided on two opposite sides of the fuel cell stack 24. Driven by the fan 25, external air is sucked into the fuel cell stack 24 from the air inlet 41 of the fuel cell stack 24 to provide the fuel cell stack 24 with oxygen required for the reaction. A hydrogen inlet 26 is provided on the upper portion of one side of the fuel cell stack 24. 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 drive device output and the fuel cell controller 31, and part of the electric energy is supplied to the electric heating element 14 for heating, so as to provide heat to the hydrogen storage tank 11. The amount of heat generated by the reaction of hydrogen and oxygen in the fuel cell stack 24 is large. The fan 25 takes out the heat through the air outlet 42 of the fuel cell stack 24 and guides it to the exhaust port along the exhaust channel 44. The hot air blows from the bottom of the hydrogen storage tank 11 along the internal space of the main riser 406 to the top of the hydrogen storage tank 11, providing part of the heat for the hydrogen storage tank 11. The hot air is discharged from the exhaust port 45 above the main riser 406. In this process, the fuel cell stack 24 is cooled and heat is provided for the hydrogen storage alloy to release hydrogen, thus achieving energy complementarity. The heat provided by the hot air to the hydrogen storage tank 11 further ensures the continuous operation of the battery-assisted bicycle, and together with the electric heating element 14, it solves the problem of continuous heat absorption of the hydrogen storage tank 11 in the current battery-assisted bicycle.

[0038] 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 foot platform 408 extending in the horizontal direction is provided at the top of the connecting pedal 404, so that the user can step on the foot platform 408 during riding, and a drain outlet 29 connecting the exhaust channel 44 with the outside atmosphere is provided at the bottom of the connecting pedal 404, and water discharged from the hydrogen outlet 27 is discharged through the drain outlet 29.

[0039] like Figure 1As shown, further, a bottle mouth valve 12 is provided on the bottle mouth of the hydrogen storage tank 11, a first end of the hydrogen supply pipeline 13 is connected to the hydrogen storage tank 11 through the bottle mouth valve 12, and a second end is connected to the hydrogen inlet 26, and a pressure-stabilizing valve 21, a gas pressure sensor 22, and an air 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-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 air intake solenoid valve 23, and is used to detect the outlet pressure of the hydrogen storage tank 11. The air intake solenoid valve 23 is used to shut down the fuel cell system when the gas pressure drops after the hydrogen in the hydrogen storage tank 11 is consumed. The main function of the air 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 air 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 air intake solenoid valve 23. Hydrogen enters the fuel cell stack 24 as a reducing agent for power generation.

[0040] like Figure 1 As shown, the power-assisted bicycle also has a seat 50, which is arranged at the top of the main vertical pipe. Further, 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 main vertical pipe 406, and the central control device 33 is arranged in the seat 50 at the top of the main vertical pipe 406, and the battery 34 provides a starting power supply for the fuel cell controller 31 and the vehicle controller 32, so that the whole power-assisted bicycle can be started with one button.

[0041] The battery-assisted bicycle also includes: a 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 lock to be opened according to the obtained unlocking information, or the central control device 33 controls the lock to be closed according to the obtained locking information, wherein the unlocking or locking information obtained by the display screen can be through the interactive information between 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 hollow device according to the QR code information, the central control device 33 controls the lock to be opened according to the obtained unlocking information, or the central control device 33 controls the lock to be closed according to the obtained locking information, thereby realizing the functions of scanning the code to unlock and lock the power-assisted bicycle.

[0042] 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.

[0043] 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, respectively, to collect data such as the gas pressure of the hydrogen storage tank 11, the current and voltage of the drive device, and transmit them to the display screen for display, so as to realize the functions of the power-assisted vehicle such as scanning the code to unlock and lock the power-assisted vehicle. 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.

[0044] Furthermore, the fuel cell assisted bicycle also includes: a temperature sensor arranged on the fuel cell stack 24, 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 closing the entire fuel cell stack 24 to protect the fuel cell stack 24, and also serves to prompt that the hydrogen in the hydrogen storage tank 11 has been consumed.

[0045] 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 stack 24 is shut down.

[0046] 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 stack 24.

[0047] 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.

[0048] 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 battery-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 stack 24, the vehicle controller 32 controls the battery 34 and the fuel cell stack 24 to power the motor at the same time to meet the power demand of the motor.

[0049] The working principle of the power system of a battery-assisted bicycle is as follows:

[0050] The solid-state hydrogen storage tank 11 provides hydrogen, and the battery 34 serves as the starting power supply of the fuel cell system. When the start button of the power-assisted vehicle 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 (such as 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 issues a high temperature alarm and shuts down the fuel cell stack 24; the fuel cell controller 31 monitors the pressure reduction of the pressure regulating valve 21 through the gas pressure sensor 22 The air pressure of the rear hydrogen supply pipeline 13 is lower than the set value when the hydrogen in the hydrogen storage tank 11 is consumed by 90%, that is, the remaining hydrogen amount in the hydrogen storage tank 11 is less than 10%, and the air pressure is lower than the set value, a low air pressure alarm is issued, the fuel cell stack 24 is turned off, 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, and when the voltage is lower than the set value, a low voltage alarm is issued, and the fuel cell stack 24 is turned off; the waste heat generated by the operation of the fuel cell stack 24 passes through the air outlet (i.e., air outlet 42) of the fuel cell stack 24 and the exhaust duct 44 into the internal space of the main riser 406, providing heat for the solid alloy hydrogen storage tank 11, and also cooling the entire fuel cell system (i.e., fuel cell stack 24), effectively utilizing the waste heat, realizing energy complementarity, and reducing system losses.

[0051] The beneficial effects of the present invention are as follows:

[0052] 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;

[0053] 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;

[0054] 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-assisted bicycle and meet the actual power requirements such as climbing a hill;

[0055] 4. The power system of battery-assisted bicycles has low loss, is low-carbon and environmentally friendly, and meets the needs of the economic and social markets.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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 battery-assisted bicycle, characterized in that: The power system comprises a hydrogen storage tank, a fuel cell stack, a control device and a drive device. The hydrogen storage tank supplies hydrogen to the fuel cell stack through a hydrogen supply pipeline, and the fuel cell stack 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 includes: a front oblique beam, a connecting pedal, and a main vertical pipe, the two ends of the connecting pedal are respectively connected to the lower end of the front oblique beam and the lower end of the main vertical pipe, the interior of the front oblique beam and the interior of the main vertical pipe are both hollow, and an exhaust passage connecting the internal space of the front oblique beam and the internal space of the main vertical pipe is provided in the connecting pedal, and an exhaust port is provided at the top of the main vertical pipe; The fuel cell stack is arranged in the front oblique beam, the hydrogen storage tank is arranged in the main vertical pipe, and the hot air discharged from the fuel cell stack enters the main vertical pipe through the exhaust passage, and is discharged from the exhaust port after flowing through the outer surface of the hydrogen storage tank. 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, vehicle controller and storage battery are arranged in the main riser, the central control device is arranged in the vehicle seat, and the storage battery provides starting power for the fuel cell controller and the vehicle controller. An air inlet is provided on the lower side wall of the front oblique beam, and the air inlet of the fuel cell stack is connected to the air inlet; A fan is provided on the air outlet of the fuel cell stack; 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 stack supplies power to the electric heating element through the control device; The air inlet and the air outlet are respectively arranged on two opposite sides of the fuel cell stack; A hydrogen outlet and a hydrogen inlet are respectively provided at the lower part and the upper part of one side of the fuel cell stack, and a gas outlet solenoid valve is provided on the hydrogen outlet; The fuel cell controller controls the heating power of the electric heating element according to the acquired load information of the driving device; A foot platform extending in the horizontal direction is provided on the top of the connecting pedal, and a drain port connecting the exhaust passage and the outside atmosphere is provided at the bottom of the connecting pedal. Water discharged from the hydrogen outlet is discharged through the drain port. The mouth of the hydrogen storage tank is provided with a mouth valve, the first end of the hydrogen supply pipeline is connected to the hydrogen storage tank through the 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 sequentially provided on the hydrogen supply pipeline from the first end to the second end. The working pressure of the hydrogen storage tank is 0.5 bar to 3 bar.

2. The power system of the battery-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 battery-assisted bicycle according to claim 1, 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.

4. The power system of the battery-assisted bicycle according to claim 1, 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, respectively, to collect the gas pressure of the hydrogen storage tank, the current of the drive device, and the voltage data to transmit 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.

5. The power system of the battery-assisted bicycle according to claim 1, 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, 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 adjusts the speed of the fan according to the temperature of the fuel cell stack measured by the temperature sensor.

6. The power system of the battery-assisted bicycle according to claim 5, 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 fuel cell stack electrode piece 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.

7. The power system of the battery-assisted bicycle according to claim 1, 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