Ammonia fuel hybrid extended range vehicle supply system and control method thereof

Abstract

The invention discloses an ammonia fuel hybrid extended range vehicle supply system and a control method thereof, and relates to the field of ammonia fuel hybrid extended range vehicles, the system comprises a liquid ammonia supply subsystem used for providing ammonia gas for an engine; the diesel oil supply subsystem is used for supplying diesel oil to the engine; the range extending power generation subsystem is used for converting mechanical energy of an engine into electric energy and supplying power to a driving motor; the pressurization subsystem is used for maintaining the pressure in the liquid ammonia tank; the electric heating subsystem is used for preheating the cooling liquid; and the electronic control unit is used for acquiring the environment temperature, the liquid ammonia tank pressure, the outlet water temperature of the cooling liquid, the charge state of the power battery, the start instruction and the stop instruction, and executing a cold start strategy, a stable operation strategy and a stop control strategy based on a preset threshold value. The problems that an existing ammonia fuel hybrid extended-range vehicle is long in low-temperature cold start time and difficult in cold start, and ammonia liquefaction is prone to occurring when the vehicle stops can be solved.

Description

Technical Field

[0001] This application relates to the field of ammonia fuel hybrid range-extended vehicles, and in particular to an ammonia fuel hybrid range-extended vehicle supply system and its control method. Background Technology

[0002] The existing ammonia-fueled range extender power logic uses a pure diesel mode at low temperatures, and then switches to ammonia-diesel mode after the coolant temperature reaches the operating state (outlet water 90±2℃, return water 80±2℃). This method results in long engine idling times, and the prolonged operation of a pure diesel engine does not meet the goal of carbon reduction. Existing ammonia-fueled power systems recover ammonia from the supply system through purging after shutdown to prevent liquefaction, but this increases vehicle costs. Summary of the Invention

[0003] The purpose of this application is to provide an ammonia fuel hybrid range extender vehicle supply system and its control method, which can solve the problems of long cold start time, difficulty in cold start, and easy ammonia liquefaction when the vehicle is stopped in existing ammonia fuel hybrid range extenders.

[0004] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides an ammonia fuel hybrid range extender vehicle supply system, comprising: The liquid ammonia supply subsystem, used to supply ammonia to the engine, includes, in sequence, a liquid ammonia tank, a liquid outlet check valve, a first solenoid valve, a liquid ammonia filter, a flow valve, a first carburetor, an ammonia filter, a shut-off valve, a pressure regulator, a gas rail assembly, and a mixer. The diesel supply subsystem, used to supply diesel fuel to the engine, includes a diesel tank, a fuel filter, a booster pump, and a common high-pressure fuel rail connected in sequence. The range extender generator system is used to convert the mechanical energy of the engine into electrical energy and supply power to the drive motor, including: a generator, an inverter connected to the generator, a power battery bidirectionally connected to the inverter, and a drive motor driven by the power battery. The pressurization subsystem, used to maintain the internal pressure of the liquid ammonia tank, includes a second solenoid valve, a pressurization regulating valve, a second vaporizer, a gaseous ammonia pump, and a bypass valve connected in parallel with the gaseous ammonia pump, connected in sequence. An electric heating subsystem for preheating coolant includes: a first electric heater located in a water tank; an electric heat tracing device wrapped around the outer wall of an ammonia pipeline between the first vaporizer and the gas rail assembly; and a second electric heater built into the first vaporizer; the first electric heater, the electric heat tracing device, and the second electric heater are all powered by the power battery. The electronic control unit is used to acquire ambient temperature, liquid ammonia tank pressure, coolant outlet temperature, power battery state of charge, start command and stop command, and execute cold start strategy, stable operation strategy and stop control strategy based on preset thresholds.

[0005] Secondly, this application provides a control method for an ammonia fuel hybrid range extender vehicle supply system, including: Upon receiving the start command, when the ambient temperature is detected to be less than or equal to a preset low temperature threshold, and the coolant temperature in the water tank is less than or equal to a first temperature threshold, and the state of charge of the power battery is greater than or equal to a first charge threshold, the first electric heater is started to preheat the coolant. When the coolant outlet temperature reaches the second temperature threshold, the engine is controlled to run in high idle speed mode; the high idle speed mode is when the engine speed is between 1000 r / min and 2000 r / min. When the outlet temperature of the coolant reaches the third temperature threshold, the second solenoid valve and the ammonia gas pump are opened, and the electric heat tracing device and the second electric heater are started simultaneously, so that the outlet temperature of the first vaporizer and the temperature of the ammonia gas pipeline reach their respective set lower limits. When the coolant outlet temperature reaches the fourth temperature threshold and the pressure inside the liquid ammonia tank is greater than or equal to the first pressure threshold, the system switches to ammonia-diesel dual-fuel combustion mode. The engine load is gradually increased as the coolant outlet temperature rises, while simultaneously increasing the ammonia substitution rate. The ammonia-diesel dual-fuel combustion mode simultaneously supplies ammonia and diesel to the engine. The ammonia substitution rate is the percentage of ammonia in the total fuel energy input under the ammonia-diesel dual-fuel combustion mode. Upon receiving a stop command, the first solenoid valve is closed to cut off the liquid ammonia supply. The engine continues to run to consume the residual ammonia in the supply line. When the pressure at the gas rail assembly inlet is less than or equal to the second pressure threshold, the first solenoid valve is kept closed, the gas rail assembly stops injecting ammonia, and diesel is injected into the engine only through the high-pressure common rail to maintain combustion, thereby reducing the amount of diesel injected and controlling the engine to shut down.

[0006] According to the specific embodiments provided in this application, this application has the following technical effects: This application introduces an electric heating subsystem powered by a power battery to actively preheat the coolant and ammonia pipelines during the cold start phase. This allows the engine to enter high idle speed operation even when the coolant outlet temperature is much lower than the traditional operating temperature, and to switch to ammonia-diesel dual-fuel mode in advance, significantly shortening the pure diesel running time and reducing cold start carbon emissions. When stopping, the liquid ammonia supply is shut off, and the engine naturally consumes the residual ammonia to achieve a residue-free shutdown, eliminating the need for a complex purging device and reducing system cost and complexity. At the same time, combined with multi-parameter sensing and hierarchical control strategies, stable ammonia vaporization, precise supply, and smooth increase in ammonia substitution rate are ensured, thereby improving system safety, reliability, and intelligence while effectively supporting carbon reduction goals. Attached Figure Description

[0007] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0008] Figure 1 This is a schematic diagram of the structure of an ammonia fuel hybrid range extender vehicle supply system provided in an embodiment of this application; Figure 2 A schematic flowchart illustrating the control method for an ammonia fuel hybrid range extender vehicle supply system provided in an embodiment of this application; Figure 3 A detailed flowchart illustrating the control method for an ammonia fuel hybrid range extender vehicle supply system provided in one embodiment of this application. Detailed Implementation

[0009] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0010] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0011] In one exemplary embodiment, such as Figure 1 As shown, an ammonia fuel hybrid range-extended vehicle supply system is provided, including: a liquid ammonia supply subsystem, a diesel supply subsystem, a range-extending generator electronic system, a turbocharging subsystem, an electric heating subsystem, and an electronic control unit (ECU). Each subsystem is described in detail below.

[0012] (1) Liquid ammonia supply subsystem.

[0013] The liquid ammonia supply subsystem, used to supply ammonia to the engine 18, includes a liquid ammonia tank 1, a liquid outlet check valve 2, a first solenoid valve 3, a liquid ammonia filter 4, a flow valve 5, a first vaporizer 6, an ammonia filter 7, a shut-off valve 8, a pressure regulator 9, a gas rail assembly 10, and a mixer 11 connected in sequence.

[0014] like Figure 1 As shown, the main ammonia fuel supply route of the liquid ammonia supply subsystem is as follows: liquid ammonia tank 1 → liquid outlet check valve 2 → first solenoid valve 3 → liquid ammonia filter 4 → overflow valve 5 → first vaporizer 6 → ammonia filter 7 → shut-off valve 8 → pressure regulator 9 → gas rail assembly 10 → mixer 11 (mixed with air) → engine 18.

[0015] The liquid ammonia tank 1 is equipped with a level gauge, a temperature sensor T1, a pressure sensor P1, a main safety valve 12, and a secondary safety valve 13.

[0016] (2) Diesel supply subsystem.

[0017] The diesel supply subsystem, used to supply diesel fuel to the engine 18, includes a diesel tank 14, a fuel filter 15, a booster pump 16, and a common rail fuel 17 connected in sequence.

[0018] like Figure 1 As shown, the diesel supply pipeline of the diesel supply subsystem is as follows: diesel tank 14 → fuel filter 15 → booster pump 16 → high-pressure common rail fuel 17 → engine 18.

[0019] (3) Range-extending generator system.

[0020] The range extender generator system is used to convert the mechanical energy of the engine 18 into electrical energy and supply power to the drive motor 21. It includes: a generator 19, an inverter 20 connected to the generator 19, a power battery 22 bidirectionally connected to the inverter 20, and a drive motor 21 driven by the power battery 22.

[0021] like Figure 1As shown, the range-extending power route of the range-extending generator system is: engine 18 → generator 19 → inverter 20 → power battery 22 → drive motor 21. Based on the state of charge of the power battery 22, electrical energy is provided to the first electric heater 23, the second electric heater 24, and the electric heat tracing device 25 (an electric heating wire wound around the outer wall of the ammonia pipeline between the first carburetor 6 and the air rail assembly 10). This heats the first carburetor 6, preheats the coolant in the water tank, and prevents the liquid ammonia from re-liquefying upon cooling by heating the pipeline temperature after the first carburetor 6 to above the critical liquefaction temperature of ammonia at different pressures. In the ammonia-diesel dual-fuel combustion mode, diesel direct injection ignites the ammonia injected into the intake manifold. If the ammonia liquefies, it will corrode the ammonia nozzle; therefore, engine 18 requires measures to prevent ammonia liquefaction.

[0022] (4) Pressure boosting subsystem.

[0023] The pressurization subsystem, used to maintain the internal pressure of the liquid ammonia tank 1, includes a second solenoid valve 26, a pressurization regulating valve 27, a second vaporizer 28, a gas ammonia pump 29, and a bypass valve 30 connected in parallel with the gas ammonia pump 29, which are connected in sequence.

[0024] like Figure 1 As shown, the ammonia fuel pressurization pipeline of the pressurization subsystem is as follows: liquid ammonia tank 1 → second solenoid valve 26 → pressurization regulating valve 27 → second vaporizer 28 → ammonia gas pump 29 (or bypass valve 30) → gas phase space above liquid ammonia tank 1. When the ammonia fuel hybrid range extender vehicle is parked in a low-temperature mining area for a long time, and the pressure inside the liquid ammonia tank 1 is lower than the first pressure threshold (approximately 1.1 MPa), the pressurization pipeline requires the ammonia gas pump 29 to operate to generate negative pressure and introduce liquid ammonia into the second vaporizer 28 for vaporization and pressurization. Once the second vaporizer 28 stably produces ammonia gas, the ammonia gas pump 29 will be bypassed, relying solely on the second vaporizer 28 to vaporize and deliver liquid ammonia to the gas phase space above liquid ammonia tank 1 to provide pressure for the supply system. When the first pressure threshold is reached, the bypass valve 30 opens, the ammonia gas pump 29 stops working, and the pressurization regulating valve 27 automatically closes.

[0025] (5) Electric heating subsystem.

[0026] An electric heating subsystem for preheating coolant includes: a first electric heater 23 located in a water tank; an electric heat tracing device 25 wrapped around the outer wall of an ammonia pipeline between the first vaporizer 6 and the gas rail assembly 10; and a second electric heater 24 built into the first vaporizer 6; the first electric heater 23, the electric heat tracing device 25, and the second electric heater 24 are all powered by the power battery 22.

[0027] The heat source for both the first vaporizer 6 and the second vaporizer 28 is coolant. After being diverted by the three-way valve 31, the coolant flows through the first proportional control valve 32 and the second proportional control valve 33 respectively before entering the first vaporizer 6 and the second vaporizer 28. The electronic control unit (ECU) dynamically adjusts the opening of the first proportional control valve 32 and the second proportional control valve 33 according to the outlet temperature of the first vaporizer 6 and the outlet temperature of the second vaporizer 28.

[0028] The working fluid for liquid ammonia vaporization is the coolant in engine 18, such as... Figure 1 As shown, the coolant vaporization pipeline is as follows: coolant outlet → three-way valve 31 → first proportional control valve 32 → first vaporizer 6 → second proportional control valve 33 → second vaporizer 28 → three-way valve 31 → engine 18 return port. The opening of the corresponding proportional control valve is controlled based on the temperature detected by temperature sensors T3 and T7, thereby controlling the coolant flow rate into and out of the vaporizer.

[0029] (6) Electronic control unit (ECU).

[0030] The electronic control unit (ECU) is used to acquire ambient temperature, pressure of liquid ammonia tank 1, outlet temperature of coolant, state of charge of power battery 22, start command and stop command, and execute cold start strategy, stable operation strategy and stop control strategy based on preset thresholds.

[0031] 1) Cold start strategy: Upon receiving a start command, when the ambient temperature is less than or equal to a preset low temperature threshold (-20℃), and the coolant temperature in the water tank is less than or equal to a first temperature threshold (around -10℃), and the state of charge of the power battery 22 is greater than or equal to a first charge threshold (around 50%), the first electric heater 23 is activated to preheat the coolant; when the coolant outlet temperature reaches a second temperature threshold (around 20℃), the engine 18 is controlled to operate in a high idle speed mode; the high idle speed mode is when the engine speed of the engine 18 is between 1000r / min and 2000r / min.

[0032] 2) Stable operation control strategy: Using the outlet temperature of the coolant as a grading criterion, when the outlet temperature of the coolant reaches multiple preset temperature thresholds in sequence, the load of the engine 18 is increased step by step, and the ammonia substitution rate is increased simultaneously; the ammonia substitution rate is the percentage of ammonia in the total fuel energy input in the ammonia-diesel dual-fuel combustion mode; the ammonia-diesel dual-fuel combustion mode is to supply ammonia and diesel to the engine 18 at the same time.

[0033] 3) Shutdown control strategy: Upon receiving a shutdown command, the first solenoid valve 3 is closed to cut off the liquid ammonia supply; the engine 18 continues to run to consume the residual ammonia in the supply line. When the pressure at the inlet of the gas rail assembly 10 is less than or equal to the second pressure threshold (around 0.5 bar), the first solenoid valve 3 is kept closed, the gas rail assembly 10 stops injecting ammonia, and only injects diesel fuel into the engine 18 through the high-pressure common rail 17 to maintain combustion, thereby reducing the amount of diesel fuel injected and controlling the engine 18 to shut down.

[0034] In one exemplary embodiment, such as Figures 2-3 As shown in the figure, this application embodiment also provides a control method for an ammonia fuel hybrid range extender vehicle supply system, including the following steps.

[0035] S1: Receive the start command. When the ambient temperature is detected to be less than or equal to the preset low temperature threshold, and the coolant temperature in the water tank is less than or equal to the first temperature threshold, and the state of charge of the power battery 22 is greater than or equal to the first charge threshold, start the first electric heater 23 to preheat the coolant.

[0036] Specifically, when the Electronic Control Unit (ECU) receives the vehicle start command, it first determines whether the ambient temperature t1 ≤ -20℃ and the coolant temperature t2 in the water tank ≤ the first temperature threshold t. a1 (Approximately -10℃) When the power battery 22 has a charge ≥ the first charge threshold Q1 (approximately 50%), if the condition is met, the engine 18 enters the preheating mode, the third solenoid valve 34 closes, the power battery 22 powers the first electric heater 23 built into the water tank, thereby preheating the coolant, and at the same time starts the engine 18 intake air heating grille heater or preheating plug until t2 ≥ 10℃.

[0037] When the state of charge of the power battery 22 is less than Q1, only the first electric heater 23 is turned on to passively preheat the coolant. After the engine 18 is working normally, it enters the range-extending mode to charge the power battery 22. When the power battery 22 charge is less than or equal to Q1, an alarm is issued that the battery charge is low and needs to be charged.

[0038] S2: When the outlet temperature of the coolant reaches the second temperature threshold, control the engine 18 to run in high idle speed mode; the high idle speed mode is when the engine speed of the engine 18 is between 1000r / min and 2000r / min.

[0039] When the coolant outlet temperature t3 ≥ the second temperature threshold t a2 (Around 20℃) Enter pure diesel start mode. The electronic control unit (ECU) adjusts the diesel injection strategy according to the current ambient temperature and coolant outlet temperature. The engine speed is controlled at 1000-2000r / min (high idle speed) to accelerate the coolant heating rate.

[0040] S3: When the outlet temperature of the coolant reaches the third temperature threshold, the second solenoid valve 26 and the ammonia gas pump 29 are opened, and the electric heat tracing device 25 and the second electric heater 24 are started simultaneously, so that the outlet temperature of the first vaporizer 6 and the ammonia gas pipeline temperature reach their respective set lower limits.

[0041] When the coolant outlet temperature t3 ≥ the third temperature threshold t a3 (40℃) The second solenoid valve 26 and the ammonia gas pump 29 are started, relying on the temperature of the coolant to build up pressure in the liquid ammonia tank 1. At this time, the ammonia gas pump 29 operates at low power, slowly building up the first pressure threshold P1 (about 1.1MPa) in the liquid ammonia tank 1. The outlet temperature t7 of the second vaporizer 28 is detected by the temperature sensor T7. If t7≤35℃, the opening of the second proportional control valve 33 needs to be adjusted. At the same time, the fourth solenoid valve 35 is closed, and the first vaporizer 6 and the electric heating device 25 begin to preheat to the target temperature (about 40℃) to prevent the ammonia gas from liquefying due to the excessive cooling of the pipeline after entering the ammonia-diesel dual-fuel combustion mode, which could lead to damage to the injection components.

[0042] S4: When the coolant outlet temperature reaches the fourth temperature threshold and the pressure inside the liquid ammonia tank 1 is greater than or equal to the first pressure threshold, switch to the ammonia-diesel dual-fuel combustion mode, and gradually increase the load on the engine 18 as the coolant outlet temperature rises, while simultaneously increasing the ammonia substitution rate; the ammonia-diesel dual-fuel combustion mode is to simultaneously supply ammonia and diesel to the engine 18; the ammonia substitution rate is the percentage of ammonia in the total fuel energy input in the ammonia-diesel dual-fuel combustion mode.

[0043] When the coolant outlet temperature t3 ≥ the fourth temperature threshold t a4 (60℃) When the pressure inside the liquid ammonia tank 1 is ≥ P1, the engine 18 enters the ammonia-diesel dual-fuel combustion mode. The load of the engine 18 slowly transitions to 25%, ensuring the load remains constant while gradually increasing the ammonia injection quantity and decreasing the diesel fuel quantity. The ammonia substitution rate is ≥ the first ammonia substitution rate threshold η1 (approximately 20%~50%). The bypass valve 30 opens, and the gas ammonia pump 29 stops working. The liquid ammonia is vaporized into ammonia gas by the first vaporizer 6 and delivered to the liquid ammonia tank 1 for self-pressurization and closed-loop control by the pressure regulating valve 27. The outlet temperature t5 of the first vaporizer 6 is detected by the temperature sensor T5, and then the opening degree of the first proportional control valve 32 and the power of the second electric heater are adjusted to ensure that t5 ≥ the outlet temperature threshold (approximately 45℃). The temperature t6 of the ammonia pipeline is detected by temperature sensor T6. If t6 ≥ the ammonia pipeline temperature threshold (about 40°C), the second solenoid valve 26 is opened. The ammonia supply pipeline after the first vaporizer 6 is heated to above the liquefaction critical temperature under different pressures by electric heating device 25. The pressure of the pipeline after the pressure regulator 9 is generally 6 bar. When the temperature is 40°C, it is greater than the ammonia liquefaction temperature (29°C) under this saturation pressure (6 bar), and a certain margin is left.

[0044] When the coolant outlet temperature t3 ≥ the fifth temperature threshold t a5 (70℃), the load of engine 18 is slowly transitioned to 50%, while the load remains unchanged. The ammonia injection quantity is gradually increased while the diesel fuel quantity is reduced. The ammonia substitution rate is ≥ the second ammonia substitution rate threshold η2 (around 50%~70%).

[0045] When the coolant outlet temperature t3 ≥ the sixth temperature threshold t a6 (80℃), the load of engine 18 is slowly transitioned to 75%, while the load remains unchanged. The ammonia injection quantity is gradually increased while the diesel fuel quantity is reduced. The ammonia substitution rate is ≥ the third ammonia substitution rate threshold η3 (around 70%~80%). When the coolant outlet temperature t3 ≥ the seventh temperature threshold t a7 (90℃), the load of engine 18 is slowly transitioned to 100%, while the load remains unchanged. The ammonia injection quantity is gradually increased while the diesel fuel quantity is reduced. The ammonia substitution rate is ≥ the fourth ammonia substitution rate threshold η4 (80%~90%).

[0046] S5: Upon receiving the stop command, the first solenoid valve 3 is closed to cut off the liquid ammonia supply; the engine 18 continues to run to consume the residual ammonia in the supply line. When the pressure at the inlet of the gas rail assembly 10 is less than or equal to the second pressure threshold, the first solenoid valve 3 is kept closed, the gas rail assembly 10 stops injecting ammonia, and only injects diesel fuel into the engine 18 through the fuel high-pressure common rail 17 to maintain combustion, thereby reducing the amount of diesel fuel injected and controlling the engine 18 to stop.

[0047] When the electronic control unit (ECU) receives a stop command, the first solenoid valve 3 closes. At this time, the engine 18 consumes the residual ammonia in the supply line. When the pressure at the inlet of the fuel rail assembly 10 (detected by the pressure sensor P2) is less than or equal to the second pressure threshold P2 (approximately 0.5 bar), the engine 18 switches to pure diesel mode (controlling the first solenoid valve 3 to remain closed, the fuel rail assembly 10 stops injecting ammonia, and only injects diesel fuel into the engine 18 through the high-pressure common rail 17 to maintain combustion). The reduced fuel injection quantity causes the engine 18 to reduce its load and return to idle speed to stop, thereby achieving a stop and preventing the problem of ammonia liquefaction caused by the residual ammonia in the ammonia supply line.

[0048] The above method also includes: during the operation of engine 18, when the outlet temperature of the first carburetor 6 is lower than the outlet temperature threshold and the temperature of the ammonia pipeline is lower than the ammonia pipeline temperature threshold, closing the first solenoid valve 3, and injecting diesel fuel into engine 18 only through the fuel high-pressure common rail 17 to maintain combustion; and simultaneously starting the second electric heater 24 and the electric heat tracing device 25.

[0049] When t5 < outlet temperature threshold and t6 < ammonia pipeline temperature threshold, an emergency alarm is triggered, switching to pure diesel mode (closing the first solenoid valve 3 and injecting diesel fuel into the engine 18 only through the fuel high-pressure common rail 17 to maintain combustion). At this time, there is a risk of ammonia liquefaction in the ammonia supply system. The shut-off valve 8 opens quickly, the fourth solenoid valve 35 opens, and the first proportional valve opens fully. The second electric heater 24 and the electric heat tracing device 25 are started simultaneously to prevent ammonia liquefaction. When t6 ≥ 40℃ and stabilizes for a certain period of time, the shut-off valve 8 closes, and the electric heating is gradually deactivated.

[0050] This application addresses the starting requirements of ammonia-fueled hybrid range-extended vehicles in low-temperature (-30℃) environments. It uses the state of charge of the power battery 22 and the coolant outlet temperature of the engine 18 as core control criteria to achieve a smooth transition from "pure diesel start-up → ammonia-diesel transition → stable dual-fuel operation." The core objective is to minimize start-up time while ensuring combustion stability, while simultaneously meeting the calibration requirements for ammonia supply flow rate, pressure, temperature, and ammonia substitution rate under different loads, avoiding problems such as poor ammonia atomization, incomplete combustion, or start-up failure due to low temperatures. Furthermore, during shutdown, logic control prevents the risk of ammonia liquefaction caused by residual ammonia in the supply pipeline.

[0051] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0052] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM).

[0053] The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.

[0054] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0055] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. An ammonia fuel hybrid range extender vehicle supply system, characterized in that, include: The liquid ammonia supply subsystem, used to supply ammonia to the engine, includes, in sequence, a liquid ammonia tank, a liquid outlet check valve, a first solenoid valve, a liquid ammonia filter, a flow valve, a first carburetor, an ammonia filter, a shut-off valve, a pressure regulator, a gas rail assembly, and a mixer. The diesel supply subsystem, used to supply diesel fuel to the engine, includes a diesel tank, a fuel filter, a booster pump, and a common high-pressure fuel rail connected in sequence. The range extender generator system is used to convert the mechanical energy of the engine into electrical energy and supply power to the drive motor, including: a generator, an inverter connected to the generator, a power battery bidirectionally connected to the inverter, and a drive motor driven by the power battery. The pressurization subsystem, used to maintain the internal pressure of the liquid ammonia tank, includes a second solenoid valve, a pressurization regulating valve, a second vaporizer, a gaseous ammonia pump, and a bypass valve connected in parallel with the gaseous ammonia pump, connected in sequence. An electric heating subsystem for preheating coolant includes: a first electric heater located in a water tank; an electric heat tracing device wrapped around the outer wall of an ammonia pipeline between the first vaporizer and the gas rail assembly; and a second electric heater built into the first vaporizer; the first electric heater, the electric heat tracing device, and the second electric heater are all powered by the power battery. The electronic control unit is used to acquire ambient temperature, liquid ammonia tank pressure, coolant outlet temperature, power battery state of charge, start command and stop command, and execute cold start strategy, stable operation strategy and stop control strategy based on preset thresholds.

2. The ammonia fuel hybrid range extender vehicle supply system according to claim 1, characterized in that, When the pressure inside the liquid ammonia tank is lower than the first pressure threshold, the gas ammonia pump operates to generate negative pressure, drawing the liquid ammonia from the tank to the second vaporizer for vaporization and pressurization; when the pressure inside the liquid ammonia tank reaches the set pressure, the bypass valve opens and the gas ammonia pump stops working.

3. The ammonia fuel hybrid range extender vehicle supply system according to claim 1, characterized in that, The cold start strategy executed by the electronic control unit includes: Upon receiving the start command, when the ambient temperature is less than or equal to a preset low temperature threshold, and the coolant temperature in the water tank is less than or equal to a first temperature threshold, and the state of charge of the power battery is greater than or equal to a first charge threshold, the first electric heater is started to preheat the coolant. When the coolant outlet temperature reaches the second temperature threshold, the engine is controlled to run in high idle speed mode; the high idle speed mode is when the engine speed is between 1000 r / min and 2000 r / min.

4. The ammonia fuel hybrid range extender vehicle supply system according to claim 1, characterized in that, The stable operation control strategy executed by the electronic control unit includes: Using the coolant outlet temperature as a grading criterion, when the coolant outlet temperature successively reaches multiple preset temperature thresholds, the engine load is gradually increased, and the ammonia substitution rate is increased simultaneously; the ammonia substitution rate is the percentage of ammonia in the total fuel energy input in the ammonia-diesel dual-fuel combustion mode; the ammonia-diesel dual-fuel combustion mode is to simultaneously supply ammonia and diesel to the engine.

5. The ammonia fuel hybrid range extender vehicle supply system according to claim 1, characterized in that, The parking control strategies executed by the electronic control unit include: Upon receiving a stop command, the first solenoid valve is closed to cut off the liquid ammonia supply. The engine continues to run to consume the residual ammonia in the supply line. When the pressure at the gas rail assembly inlet is less than or equal to the second pressure threshold, the first solenoid valve is kept closed, the gas rail assembly stops injecting ammonia, and diesel is injected into the engine only through the high-pressure common rail to maintain combustion, thereby reducing the amount of diesel injected and controlling the engine to shut down.

6. The ammonia fuel hybrid range extender vehicle supply system according to claim 1, characterized in that, The heat source for both the first vaporizer and the second vaporizer is coolant. After being diverted by a three-way valve, the coolant flows through the first proportional control valve and the second proportional control valve respectively before entering the first vaporizer and the second vaporizer. The electronic control unit dynamically adjusts the opening of the first proportional control valve and the second proportional control valve according to the outlet temperature of the first vaporizer and the outlet temperature of the second vaporizer.

7. A control method for an ammonia fuel hybrid range extender vehicle supply system as described in any one of claims 1-6, characterized in that, include: Upon receiving the start command, when the ambient temperature is detected to be less than or equal to a preset low temperature threshold, and the coolant temperature in the water tank is less than or equal to a first temperature threshold, and the state of charge of the power battery is greater than or equal to a first charge threshold, the first electric heater is started to preheat the coolant. When the coolant outlet temperature reaches the second temperature threshold, the engine is controlled to run in high idle speed mode; the high idle speed mode is when the engine speed is between 1000 r / min and 2000 r / min. When the outlet temperature of the coolant reaches the third temperature threshold, the second solenoid valve and the ammonia gas pump are opened, and the electric heat tracing device and the second electric heater are started simultaneously, so that the outlet temperature of the first vaporizer and the temperature of the ammonia gas pipeline reach their respective set lower limits. When the coolant outlet temperature reaches the fourth temperature threshold and the pressure inside the liquid ammonia tank is greater than or equal to the first pressure threshold, the system switches to ammonia-diesel dual-fuel combustion mode. The engine load is gradually increased as the coolant outlet temperature rises, while simultaneously increasing the ammonia substitution rate. The ammonia-diesel dual-fuel combustion mode simultaneously supplies ammonia and diesel to the engine. The ammonia substitution rate is the percentage of ammonia in the total fuel energy input under the ammonia-diesel dual-fuel combustion mode. Upon receiving a stop command, the first solenoid valve is closed to cut off the liquid ammonia supply. The engine continues to run to consume the residual ammonia in the supply line. When the pressure at the gas rail assembly inlet is less than or equal to the second pressure threshold, the first solenoid valve is kept closed, the gas rail assembly stops injecting ammonia, and diesel is injected into the engine only through the high-pressure common rail to maintain combustion, thereby reducing the amount of diesel injected and controlling the engine to shut down.

8. The control method for the ammonia fuel hybrid range extender vehicle supply system according to claim 7, characterized in that, When the pressure inside the liquid ammonia tank reaches the first pressure threshold, the bypass valve is opened and the gas ammonia pump is stopped.

9. The control method for the ammonia fuel hybrid range extender vehicle supply system according to claim 7, characterized in that, Also includes: During engine operation, when the outlet temperature of the first carburetor is lower than the outlet temperature threshold and the temperature of the ammonia pipeline is lower than the ammonia pipeline temperature threshold, the first solenoid valve is closed, and diesel fuel is injected into the engine only through the high-pressure common rail to maintain combustion; and the second electric heater and electric heat tracing device are started simultaneously.

10. The control method for the ammonia fuel hybrid range extender vehicle supply system according to claim 7, characterized in that, When the state of charge of the power battery is less than the first charge threshold, only the first electric heater is turned on to passively preheat the coolant.

Images