Driving device based on liquid nitrogen expansion as power source and pneumatic automobile

Abstract

The invention relates to a driving device based on liquid nitrogen expansion as a power source and a pneumatic automobile, the driving device comprises a liquid nitrogen storage system, a gasification pressurization system, a pneumatic power system, a control system and an energy recovery system, the liquid nitrogen storage system is used for storing liquid nitrogen; the gasification pressurization system is used for converting liquid nitrogen into high-pressure nitrogen by recovering environment heat or brake waste heat; the pneumatic power system is used for receiving the high-pressure nitrogen and outputting mechanical energy to drive wheels; the control system is used for dynamically adjusting nitrogen flow and pressure according to the vehicle speed signal; the energy recovery system is used for generating electricity through braking energy and charging the storage battery. The device has the advantages that only nitrogen is discharged, pollutants such as carbon dioxide, nitric oxide or particulate matter are avoided, and real zero discharge is achieved. In addition, renewable energy sources such as wind energy and solar energy can be utilized for air separation during production of liquid nitrogen, so that carbon emission in the whole life cycle is extremely low, and the requirements of global environmental protection trend and sustainable development are met.

Description

Technical Field

[0001] The invention relates to a driving device and a pneumatic vehicle based on liquid nitrogen expansion as a power source, belonging to the field of pneumatics. Background Art

[0002] Currently, the global automotive powertrain relies primarily on traditional fuel and electric vehicle technologies. Fuel-powered vehicles, which burn gasoline or diesel to power internal combustion engines, are mature and offer long ranges, but their high costs and environmental pollution are increasingly prominent. Electric vehicles, on the other hand, utilize batteries as their power source and electric motors to drive the vehicle, offering the advantages of zero emissions and low noise. However, they are limited by low battery energy density, long charging times, and insufficient infrastructure, making them a difficult candidate to completely replace fuel-powered vehicles. While both technologies have achieved some progress in their respective fields, their limitations in terms of economic efficiency, environmental friendliness, and ease of use have prompted the industry to seek better solutions.

[0003] Fuel-powered vehicles have low combustion efficiency, and their exhaust emissions contribute to severe air pollution and greenhouse gas emissions. Furthermore, their reliance on non-renewable fossil fuels increases the risk of resource depletion. According to the International Energy Agency (IEA), global transportation accounts for 24% of total CO2 emissions, with the majority coming from fuel-powered vehicles. While environmentally friendly, electric vehicles (EVs) have limited range, long charging times, and the high cost of high-performance batteries, limiting their widespread adoption. Furthermore, the construction of charging station networks still needs to be improved, especially in remote areas, further hindering the widespread adoption of EVs. These issues demonstrate that existing technologies are clearly insufficient to meet the demands of future sustainable development. Summary of the Invention

[0004] In order to overcome the defects of the prior art, the present invention provides a driving device and a pneumatic vehicle based on liquid nitrogen expansion as a power source. The technical solution of the present invention is:

[0005] A driving device based on liquid nitrogen expansion as a power source, including a liquid nitrogen storage system, a gasification and pressurization system, a pneumatic power system, a control system and an energy recovery system.

[0006] The liquid nitrogen storage system is used to store liquid nitrogen; the gasification and pressurization system is used to gasify liquid nitrogen into high-pressure nitrogen by recovering ambient heat or brake waste heat; the pneumatic power system is used to receive high-pressure nitrogen and output mechanical energy to drive the wheels; the control system is used to dynamically adjust the nitrogen flow and pressure according to the vehicle speed signal; and the energy recovery system is used to generate electricity through braking energy and charge the battery.

[0007] The liquid nitrogen storage system comprises a vacuum insulated storage tank (1) for storing liquid nitrogen at -196°C; the gasification and pressurization system comprises a heat exchanger; the pneumatic power system comprises a pneumatic engine (3); the energy recovery system comprises a magnetic brake (7); the control system comprises a flow meter (4), a pressure sensor (5) and a controller (6); the flow meter (4) and the pressure sensor (5) are sequentially installed on a pipeline between the vacuum insulated storage tank (1) and the pneumatic engine (3); the heat exchanger, the flow meter (4), the pressure sensor (5), the battery, the pneumatic engine (3) and the magnetic brake (7) are all connected to the controller.

[0008] The heat exchanger converts liquid nitrogen into high-pressure nitrogen with a pressure range of 10 to 30 MPa by recovering ambient heat or brake waste heat.

[0009] The controller (6) adopts a dynamic pressure matching algorithm, and its implementation steps include:

[0010] 6.1 Obtain vehicle speed signal v and nitrogen pressure P in real time;

[0011] 6.2 Calculate the target pressure according to the formula Ptarget = k·v2 + b, where k is the torque coefficient and b is the basic pressure compensation value;

[0012] 6.3 Adjust the valve opening through PID to make P approach P target in real time.

[0013] The pneumatic engine (3) is a multi-stage expansion turbine structure, and its isothermal expansion efficiency satisfies: η=1-T low temperature / T high temperature; wherein T low temperature=-196°C, and T high temperature is raised to above the ambient temperature through a heat exchanger.

[0014] The power generation of the magnetic brake (7) is determined by the following formula:

[0015] Where B is the magnetic induction intensity of the permanent magnet, A is the cross-sectional area of ​​the coil, l is the length of the wire, n is the wheel speed, and R is the total resistance of the circuit.

[0016] The heat exchanger is integrated with a preheating module, and its preheating temperature Tpreheat satisfies: T 预热 >T 环境 -ΔT, wherein ΔT is an anti-icing threshold value set according to the ambient humidity and is powered by a battery; the thickness d of the carbon fiber composite material layer of the vacuum insulation storage tank (1) satisfies: Where Q heat leakage is the maximum allowable heat leakage, k is the thermal conductivity of the material, and ΔT = 196°C; the control system integrates a safety pressure relief module. When the pressure P real time > 30 MPa, the pressure relief rate Q satisfies: Q = α·(P real time - 30); where α is the pressure relief coefficient, which is calibrated through experiments.

[0017] The liquid nitrogen filling amount m is based on the remaining liquid nitrogen amount m 剩余 And the endurance requirement D is dynamically calculated: Among them, E 公里 is the energy consumption per 100 kilometers, in MJ / km, η 系统 For the overall efficiency of the system;

[0018] The relationship between the output torque τ of the pneumatic engine (3) and the nitrogen flow rate F is: Where β is the engine structure constant, P 入口 and P 出口 are the engine inlet and outlet pressures respectively.

[0019] A pneumatic car comprises the driving device based on liquid nitrogen expansion as a power source.

[0020] The advantages of the present invention are:

[0021] 1. Excellent Environmental Performance: The pneumatic vehicle of this invention demonstrates outstanding environmental performance. Liquid nitrogen vaporizes and expands at room temperature, emitting only nitrogen gas, without pollutants such as carbon dioxide, nitrogen oxides, or particulate matter, achieving true zero emissions. Furthermore, liquid nitrogen production utilizes renewable energy sources such as wind and solar energy for air separation, resulting in extremely low carbon emissions throughout its lifecycle, in line with global environmental trends and sustainable development requirements.

[0022] 2. Low economic cost: Comparable to electric vehicles and far lower than traditional fuel vehicles, significantly reducing user costs. This solves the problem of long charging times for electric vehicles, improves vehicle efficiency, and reduces user waiting time.

[0023] 3. Highly Efficient Power System: The pneumatic engine of this invention utilizes a multi-stage expansion turbine structure, optimizing expansion efficiency and ensuring highly efficient power output. Furthermore, the intelligent control system utilizes a dynamic pressure matching algorithm to adjust nitrogen flow and pressure in real time based on vehicle speed signals, ensuring precise and efficient power output. A heat exchanger recycles ambient heat or brake waste heat to convert liquid nitrogen into high-pressure nitrogen, with a pressure range of 10 to 30 MPa, further improving the overall energy efficiency of the system.

[0024] 4. Reliable safety performance: In terms of safety, the present invention adopts a number of designs to ensure safe use. The vacuum insulated storage tank is made of carbon fiber composite material, which is lightweight and resistant to ultra-low temperatures (-196°C), effectively preventing the volatilization and leakage of liquid nitrogen during storage. The heat exchanger is integrated with a preheating module to prevent the environment from freezing; the control system is integrated with a safety pressure relief module, which automatically relieves pressure when the pressure exceeds 30MPa, ensuring that the system pressure is always within a safe range, avoiding safety accidents that may be caused by excessive pressure.

[0025] 5. Energy Recovery and Reuse: This invention excels in energy recovery. The magnetic brake generates electricity by cutting magnetic lines of force during braking, charging the battery and improving energy efficiency while supporting the operation of the vehicle's electrical system. The power generated by the magnetic brake is calculated using a formula that considers multiple parameters, including the magnetic induction intensity of the permanent magnet, the coil's cross-sectional area, the wire length, the wheel speed, and the total circuit resistance. This maximizes energy recovery efficiency, further enhancing the system's economic and environmental performance.

[0026] 6. Broad Application Prospects: This invention is particularly well-suited for fixed-route or short-distance transportation scenarios, such as cold chain logistics and closed campuses. These scenarios place high demands on environmental protection and rapid charging, and liquid nitrogen vehicles can fully leverage their advantages. Furthermore, this invention can be combined with battery range extension technology to form a hybrid system, further enhancing endurance and applicability. This provides a competitive solution for the new energy vehicle sector and holds broad market prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the main structure of the pneumatic car of the present invention. DETAILED DESCRIPTION

[0028] The present invention will be further described below with reference to specific embodiments, and the advantages and features of the present invention will become clearer as the description proceeds. However, these embodiments are merely exemplary and do not constitute any limitation to the scope of the present invention. It should be understood by those skilled in the art that the details and forms of the technical solutions of the present invention may be modified or replaced without departing from the spirit and scope of the present invention, and such modifications and replacements fall within the scope of protection of the present invention.

[0029] See also Figure 1 The present invention relates to a driving device based on liquid nitrogen expansion as a power source, comprising a liquid nitrogen storage system, a gasification and pressurization system, a pneumatic power system, a control system, and an energy recovery system. The liquid nitrogen storage system is used to store liquid nitrogen; the gasification and pressurization system is used to gasify liquid nitrogen into high-pressure nitrogen by recovering ambient heat or brake waste heat; the pneumatic power system is used to receive the high-pressure nitrogen and output mechanical energy to drive the wheels; the control system is used to dynamically adjust the nitrogen flow and pressure according to a vehicle speed signal; and the energy recovery system is used to generate electricity through braking energy and charge a battery.

[0030] The liquid nitrogen storage system includes a vacuum insulated storage tank 1 for storing -196°C liquid nitrogen; the gasification and pressurization system includes a heat exchanger; the pneumatic power system includes a pneumatic engine 3; the energy recovery system includes a magnetic brake 7; and the control system includes a flow meter 4, a pressure sensor 5, and a controller 6. The flow meter 4 and pressure sensor 5 are sequentially installed on the pipeline between the vacuum insulated storage tank 1 and the pneumatic engine 3. The heat exchanger, flow meter 4, pressure sensor 5, battery 8, pneumatic engine 3, and magnetic brake 7 are all connected to the controller. A sealing joint 9 is installed at the connection between the vacuum insulated storage tank 1 and the pipeline.

[0031] Among them, (1) liquid nitrogen storage system has the following advantages:

[0032] (1) High-efficiency insulation: The use of vacuum insulated storage tanks greatly reduces the volatilization and leakage of liquid nitrogen during storage, ensuring a stable supply of liquid nitrogen.

[0033] (2) Lightweight design: Use carbon fiber composite materials to reduce the weight of the tank and improve the overall performance and energy efficiency of the vehicle.

[0034] (2) The gasification boosting system has the following advantages:

[0035] (1) Efficient utilization of waste heat: Recover ambient heat or brake waste heat through a heat exchanger, and convert liquid nitrogen into high-pressure nitrogen with a pressure of 10 to 30 MPa, thereby improving energy utilization efficiency.

[0036] (2) Anti-icing design: The integrated preheating module effectively prevents the environment from icing and ensures stable operation of the system in low temperature environments.

[0037] (3) Pneumatic power system has the following advantages:

[0038] (1) High expansion efficiency: It adopts a multi-stage expansion turbine structure to optimize the expansion efficiency. The theoretical isothermal expansion efficiency is as high as 50%, achieving efficient power output.

[0039] (2) Fast response: Pneumatic engines have fast response characteristics, instantaneous torque output response, and acceleration performance that is better than traditional fuel vehicles, providing an excellent driving experience.

[0040] (4) The control system has the following advantages:

[0041] (1) Intelligent Regulation: Using a dynamic pressure matching algorithm, the nitrogen flow and pressure are adjusted in real time according to the vehicle speed signal to ensure accurate and efficient power output.

[0042] (2) Safety protection: The integrated safety pressure relief module automatically releases pressure when the pressure exceeds 30MPa, ensuring the safety of the system pressure and avoiding safety accidents caused by excessive pressure.

[0043] (V) The energy recovery system has the following advantages:

[0044] (1) Braking energy recovery: The magnetic brake generates electricity by cutting magnetic lines during braking, charging the battery, improving energy utilization efficiency and supporting the operation of the vehicle's electrical system.

[0045] (2) Accurate calculation: The power generation is calculated using a formula involving multiple parameters such as the magnetic induction intensity of the permanent magnet, the cross-sectional area of ​​the coil, the length of the wire, the wheel speed, and the total resistance of the circuit to ensure maximum energy recovery efficiency.

[0046] The present invention as a whole achieves the following advantages:

[0047] Efficient collaboration: All systems work closely together to form a complete power cycle, from liquid nitrogen storage, gasification and pressurization, power output to energy recovery, to achieve efficient, environmentally friendly and safe driving.

[0048] Environmentally friendly and economical: The entire system only emits nitrogen, without pollutants, with low operating costs, fast liquid nitrogen refilling, easy use and significant economic benefits.

[0049] Widely applicable: Particularly suitable for fixed-route or short-distance transportation scenarios such as cold chain logistics and closed parks. It can be combined with battery range extension technology to expand the scope of application and enhance market competitiveness.

[0050] Furthermore, the heat exchanger converts liquid nitrogen into high-pressure nitrogen with a pressure range of 10 to 30 MPa by recovering ambient heat or brake waste heat.

[0051] Furthermore, the controller 6 adopts a dynamic pressure matching algorithm, and its implementation steps include:

[0052] 6.1 Real-time acquisition of vehicle speed signal v and nitrogen pressure P 实时 ;

[0053] 6.2 According to formula P 目标 =k·v 2 +b calculates the target pressure, where k is the torque coefficient and b is the basic pressure compensation value;

[0054] 6.3 Adjust the valve opening by PID to make P 实时 Approaching P target P 目标 .

[0055] Based on the settings in the above steps, the following advantages are achieved:

[0056] (1) Real-time monitoring and adjustment: Controller 6 can obtain vehicle speed signals and nitrogen pressure in real time, and dynamically adjust nitrogen flow and pressure according to the actual driving status of the vehicle, ensuring that the vehicle can obtain accurate power output under different driving conditions and improving the driving experience.

[0057] (2) Personalized power output: By calculating the target pressure through a formula, the controller can provide personalized power output according to different vehicle speeds and driving requirements to meet the vehicle's power requirements under different working conditions such as acceleration, cruising, and deceleration.

[0058] (3) Instant adjustment: The PID valve opening is used to quickly respond to changes in vehicle speed and pressure deviations, and the nitrogen flow and pressure are adjusted in time to make the actual pressure quickly approach the target pressure, ensuring the timeliness and accuracy of the vehicle's power output and improving the vehicle's controllability and stability.

[0059] (4) Pressure stability: Through the dynamic pressure matching algorithm, the controller can effectively reduce the fluctuation of nitrogen pressure and maintain the stability of system pressure, thereby improving the working stability and reliability of the pneumatic engine and reducing the power output fluctuation and failure risk caused by unstable pressure.

[0060] (5) Optimize nitrogen usage: Accurately control nitrogen flow and pressure to avoid excessive use and waste of nitrogen, improve nitrogen utilization efficiency, reduce vehicle operating costs, and reduce the frequency of liquid nitrogen refueling, thereby improving vehicle convenience.

[0061] (6) Adaptability to different road conditions: The algorithm can automatically adjust the nitrogen pressure according to different vehicle speeds and road conditions, so that the vehicle can maintain optimal power performance and fuel economy under various driving conditions, enhancing the adaptability and versatility of the vehicle.

[0062] Furthermore, the pneumatic engine 3 is a multi-stage expansion turbine structure, and its isothermal expansion efficiency satisfies: η = 1-T 低温 / T 高温 ; where T 低温 =-196℃, T 高温 Raised to above ambient temperature through a heat exchanger.

[0063] The pneumatic engine 3 adopts a multi-stage expansion turbine structure. This design has the following advantages:

[0064] (1) Efficient expansion: The multi-stage expansion turbine structure can gradually reduce the pressure of nitrogen and efficiently convert the pressure energy into mechanical energy, thereby optimizing the expansion process and improving energy conversion efficiency.

[0065] (2) High theoretical efficiency: According to the formula calculation, the theoretical isothermal expansion efficiency can reach about 50%, ensuring the high efficiency of the pneumatic engine in converting high-pressure nitrogen into mechanical energy.

[0066] (3) Strong adaptability: The pneumatic engine can be flexibly adjusted according to different working conditions and pressure conditions to meet the power requirements of the vehicle under different driving conditions.

[0067] (4) Environmental protection: The pneumatic engine only emits nitrogen during operation, without carbon dioxide or other pollutants, which meets environmental protection requirements.

[0068] (5) Fast response: Pneumatic engines have fast response characteristics, instantaneous torque output response, and acceleration performance is better than traditional fuel engines, providing an excellent driving experience.

[0069] Furthermore, the power generation of the magnetic brake 7 is determined by the following formula:

[0070] Where B is the magnetic induction intensity of the permanent magnet, A is the cross-sectional area of ​​the coil, l is the length of the wire, n is the wheel speed, and R is the total resistance of the circuit.

[0071] The arrangement of the magnetic brake has the following advantages:

[0072] (1) Efficient energy recovery: During the braking process, the magnetic brake generates an induced current by cutting the magnetic lines of force, which charges the battery, effectively recovering the braking energy and improving energy utilization efficiency.

[0073] (2) Accurate calculation: The calculation of power generation involves multiple parameters (such as magnetic induction intensity, coil cross-sectional area, wire length, wheel speed, and total circuit resistance) to ensure maximum energy recovery efficiency.

[0074] (3) Simple and reliable structure: The structure of the magnetic brake is similar to that of the general electromagnetic brake, with high reliability and durability and low maintenance cost.

[0075] (4) Auxiliary power support: The recovered electrical energy can be used for the vehicle’s auxiliary systems such as lighting, signaling, and audio, reducing dependence on liquid nitrogen power and further improving the economy of the system.

[0076] (5) Smooth braking: Magnetic brakes can provide smooth braking force, reduce impact and vibration during braking, and improve driving comfort.

[0077] It should be noted that the structural design of the pneumatic engine 3 and the magnetic brake 7, and their coordinated operation, give the entire drive system significant advantages in terms of efficiency, environmental protection, economy, and reliability. The pneumatic engine achieves efficient power output through a multi-stage expansion turbine structure, while the magnetic brake further improves the system's energy efficiency through energy recovery. Together, they provide the vehicle with excellent performance and environmental protection.

[0078] Furthermore, the heat exchanger is integrated with a preheating module, and its preheating temperature Tpreheat satisfies: T 预热 >T 环境-ΔT, where ΔT is the anti-icing threshold set according to the ambient humidity and is powered by a battery; the thickness d of the carbon fiber composite material layer of the vacuum insulated storage tank 1 satisfies: Where Q heat leakage is the maximum allowable heat leakage, k is the thermal conductivity of the material, ΔT = 196 ° C; the control system integrates a safety pressure relief module, when the pressure P is greater than 30 MPa, the pressure relief rate Q satisfies: Q = α (P 实时 -30); where α is the pressure relief coefficient, which is calibrated through experiments.

[0079] The heat exchanger has the following advantages:

[0080] (1) Anti-icing protection: Through the preheating module, the heat exchanger can prevent icing in low temperature or high humidity environments, ensuring stable operation of the system under various environmental conditions.

[0081] (2) Efficient heat exchange: The preheating module improves the heat exchange efficiency, reduces the energy loss during the gasification process, and improves the energy efficiency of the overall system.

[0082] (3) Strong environmental adaptability: It can dynamically adjust the preheating temperature according to the ambient humidity, adapt to different climatic conditions, and ensure the reliability of the system in extreme weather conditions.

[0083] (4) Reasonable energy utilization: The preheating module is powered by a battery, which rationally utilizes the vehicle's electrical energy and avoids additional energy waste.

[0084] The vacuum insulation storage tank has the following advantages:

[0085] (1) High-efficiency insulation: The vacuum insulation design greatly reduces the volatilization and leakage of liquid nitrogen during storage, ensuring a stable supply of liquid nitrogen.

[0086] (2) Lightweight design: The use of carbon fiber composite materials reduces the weight of the tank and improves the overall performance and energy efficiency of the vehicle.

[0087] (3) Low temperature resistance: Carbon fiber composite materials have excellent low temperature resistance, ensuring that the storage tank can still work normally at extremely low temperatures of -196°C.

[0088] (4) Accurate design: The thickness of the carbon fiber composite material layer is calculated through a formula to ensure that the tank meets the insulation requirements while minimizing material usage and reducing costs.

[0089] The control system has the following advantages:

[0090] (1) Safety protection: When the system pressure exceeds the safety threshold (30MPa), the safety pressure relief module automatically starts to quickly release excess pressure to prevent explosions or other safety accidents caused by excessive pressure.

[0091] (2) Precise control: The pressure relief rate is calibrated through experiments to ensure that the pressure can be released quickly and stably under different pressure conditions, protecting the safety of the system and components.

[0092] (3) High reliability: The integrated design enables the pressure relief module to work closely with the control system, with rapid response and high reliability.

[0093] (4) Easy maintenance: The pressure relief module has a simple design and is easy to maintain, which reduces the maintenance cost and complexity of the system.

[0094] It should be noted that in this invention, the heat exchanger, vacuum insulated storage tank 1, and integrated safety pressure relief module of the control system together form an efficient, safe, and reliable system. The heat exchanger's preheating module prevents icing, improving heat exchange efficiency. The vacuum insulated storage tank ensures stable storage of liquid nitrogen through efficient insulation and lightweight design. The safety pressure relief module provides reliable pressure protection, ensuring safe operation of the system under various operating conditions. These design features collectively enhance the performance and reliability of the entire drive unit.

[0095] The liquid nitrogen filling amount m is based on the remaining liquid nitrogen amount m 剩余 And the endurance requirement D is dynamically calculated: Among them, E 公里 is the energy consumption per 100 kilometers, in MJ / km, η 系统 For the overall efficiency of the system;

[0096] The relationship between the output torque τ of the pneumatic engine (3) and the nitrogen flow rate F is: Where β is the engine structure constant, P 入口 and P 出口 are the engine inlet and outlet pressures respectively.

[0097] In addition, the present invention also relates to a pneumatic vehicle, comprising the driving device based on liquid nitrogen expansion as a power source.

[0098] The working principle of the driving device of the present invention is as follows:

[0099] (1) Liquid nitrogen storage and gasification pressurization

[0100] Liquid nitrogen storage: Liquid nitrogen (LN) is stored in vacuum-insulated tanks at -196°C. The tanks are constructed of carbon fiber composite materials, which are lightweight and cryogenically resistant, ensuring that the liquid nitrogen does not volatilize or leak during storage.

[0101] Gasification and pressurization: When the vehicle starts, liquid nitrogen enters the heat exchanger through a pipe. The heat exchanger uses ambient heat or brake waste heat to vaporize the liquid nitrogen into high-pressure nitrogen (10-30 MPa). This process is accomplished through a highly efficient heat exchange design, avoiding efficiency losses caused by frost.

[0102] (2) Power output

[0103] High-pressure nitrogen enters the pneumatic engine, driving the piston or turbine, converting the pressure energy into mechanical energy to drive the wheels. The pneumatic engine utilizes a multi-stage expansion turbine structure to optimize expansion efficiency, achieving a theoretical isothermal expansion efficiency of 50%. After driving the engine, the nitrogen is discharged directly into the atmosphere, achieving zero pollution.

[0104] (3) Energy recovery

[0105] When the vehicle brakes or drives downhill, the rotation of the wheels drives the permanent magnets in the magnetic brake to rotate, cutting the coil to generate an induced current that charges the battery. This process is regulated by a controller to ensure maximum energy recovery efficiency.

[0106] (4) Intelligent control

[0107] The control system monitors nitrogen flow and pressure in real time through flow meters and pressure sensors, dynamically adjusting them based on vehicle speed. The controller uses a dynamic pressure matching algorithm to calculate the target pressure and adjust valve opening in real time, ensuring smooth and efficient power delivery.

[0108] (5) Driver control

[0109] The driver controls the vehicle's acceleration and deceleration using a handle on the control console 11. Pushing the handle forward increases the nitrogen flow rate, accelerating the vehicle; pulling the handle backward decreases the nitrogen flow rate, slowing the vehicle. To reverse, the driver uses a control button on the console to change the air intake direction of the pneumatic engine.

[0110] (6) Instrument panel display

[0111] The instrument panel 10 displays key vehicle operating parameters in real time, including nitrogen pressure, vehicle speed, remaining liquid nitrogen, and battery charge. This information helps the driver understand vehicle status and ensure safe driving. If nitrogen pressure is insufficient or battery charge is low, an alarm will sound, reminding the driver to refill liquid nitrogen or charge the battery immediately.

[0112] Through these steps, liquid nitrogen storage, vaporization, power output, energy recovery, and intelligent control are achieved, forming an efficient, environmentally friendly, and safe drive system. The driver interacts with the system through the control console and instrument panel to ensure smooth operation and efficient management of the vehicle.

[0113] Finally, it should be noted that the production, storage and transportation costs of liquid nitrogen are relatively high, and liquid oxygen or liquid hydrogen can be used as a substitute.

[0114] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A driving device based on liquid nitrogen expansion as a power source, characterized in that: Including liquid nitrogen storage system, gasification and pressurization system, pneumatic power system, control system and energy recovery system, The liquid nitrogen storage system is used to store liquid nitrogen; the gasification and pressurization system is used to gasify liquid nitrogen into high-pressure nitrogen by recovering ambient heat or brake waste heat; the pneumatic power system is used to receive high-pressure nitrogen and output mechanical energy to drive the wheels; the control system is used to dynamically adjust the nitrogen flow and pressure according to the vehicle speed signal; and the energy recovery system is used to generate electricity through braking energy and charge the battery.

2. The driving device based on liquid nitrogen expansion as a power source according to claim 1, characterized in that: The liquid nitrogen storage system comprises a vacuum insulated storage tank (1) for storing liquid nitrogen at -196°C; the gasification and pressurization system comprises a heat exchanger; the pneumatic power system comprises a pneumatic engine (3); the energy recovery system comprises a magnetic brake (7); the control system comprises a flow meter (4), a pressure sensor (5) and a controller (6); the flow meter (4) and the pressure sensor (5) are sequentially installed on a pipeline between the vacuum insulated storage tank (1) and the pneumatic engine (3); the heat exchanger, the flow meter (4), the pressure sensor (5), the battery, the pneumatic engine (3) and the magnetic brake (7) are all connected to the controller.

3. The driving device based on liquid nitrogen expansion as a power source according to claim 1 or 2, characterized in that: The heat exchanger converts liquid nitrogen into high-pressure nitrogen with a pressure range of 10 to 30 MPa by recovering ambient heat or brake waste heat.

4. The driving device based on liquid nitrogen expansion as a power source according to claim 3, characterized in that: The controller (6) adopts a dynamic pressure matching algorithm, and its implementation steps include: 6.1 Real-time acquisition of vehicle speed signal v and nitrogen pressure P 实时 ; 6.2 According to formula P 目标 =k·v 2 +b calculates the target pressure, where k is the torque coefficient and b is the basic pressure compensation value; 6.3 Adjust the valve opening by PID to make P 实时 Approaching P target P 目标 .

5. The driving device based on liquid nitrogen expansion as a power source according to claim 4, characterized in that: The pneumatic engine (3) is a multi-stage expansion turbine structure, and its isothermal expansion efficiency satisfies: Where T 低温 =-196℃, T 高温 Raised to above ambient temperature through a heat exchanger.

6. The driving device based on liquid nitrogen expansion as a power source according to claim 5, characterized in that: The power generation of the magnetic brake (7) is determined by the following formula: Where B is the magnetic induction intensity of the permanent magnet, A is the cross-sectional area of ​​the coil, l is the length of the wire, n is the wheel speed, and R is the total resistance of the circuit.

7. The driving device based on liquid nitrogen expansion as a power source according to claim 6, characterized in that: The heat exchanger is integrated with a preheating module, and its preheating temperature T 预热 Satisfaction: T 预热 ≥T 环境 -ΔT, wherein ΔT is an anti-icing threshold value set according to the ambient humidity and is powered by a battery; the thickness d of the carbon fiber composite material layer of the vacuum insulation storage tank (1) satisfies: where Q 漏热 is the maximum allowable heat leakage, k is the thermal conductivity of the material, ΔT = 196 ° C; the control system integrates a safety pressure relief module, when the pressure P 实时 When the pressure is >30MPa, the pressure relief rate Q satisfies: Q=α·(P 实时 -30); where α is the pressure relief coefficient, which is calibrated through experiments.

8. The driving device based on liquid nitrogen expansion as a power source according to claim 6, characterized in that: The liquid nitrogen filling amount m is based on the remaining liquid nitrogen amount m 剩余 And the endurance requirement D is dynamically calculated: Among them, E 公里 is the energy consumption per 100 kilometers, in MJ / km, η 系统 For the overall efficiency of the system; The relationship between the output torque τ of the pneumatic engine (3) and the nitrogen flow rate F is: Where β is the engine structure constant, P 入口 and P 出口 are the engine inlet and outlet pressures respectively.

9. A pneumatic car, characterized in that: A driving device comprising the driving device according to any one of claims 1 to 8, which is based on liquid nitrogen expansion as a power source.

Images