Ammonia supply system for ammonia engine and control method thereof

Abstract

The present application relates to a kind of ammonia engine ammonia supply system and its control method, it includes: liquid ammonia tank;Pressure circuit assembly;The pressure circuit assembly includes the water bath heater of pressure line by first pipeline with the liquid ammonia tank is communicated, the first ammonia gas filter is communicated with the water bath heater of pressure line by second pipeline, one end is communicated with the first ammonia gas filter and the other end is communicated with the liquid ammonia tank third pipeline, first solenoid valve is installed on the first pipeline, ammonia gas booster pump is installed on the third pipeline, and check valve is installed on the third pipeline and located downstream of the ammonia gas booster pump;Injection circuit assembly.By using pressure circuit assembly and injection circuit assembly etc. Structure cooperation, the design of ammonia supply system of liquid storage to gaseous injection can be realized.

Description

Technical Field

[0001] This invention relates to the field of automotive engine technology, and specifically to an ammonia supply system, and a control method for an ammonia engine. Background Technology

[0002] Due to its zero-carbon nature, ammonia produces no CO2 emissions after combustion, meeting the "dual-carbon" target requirements. It can be liquefied at room temperature with a pressure of only 0.6–1 MPa, and its volumetric energy density is 1.5 times that of liquid hydrogen. Furthermore, mature ammonia storage and transportation infrastructure already exists globally. Therefore, research on ammonia (NH3) as an internal combustion engine fuel has received widespread attention in recent years, becoming an important direction for replacing traditional fossil fuels. In addition, "green ammonia" can be synthesized from hydrogen produced from renewable energy sources, or "blue ammonia" can be produced by combining it with carbon capture technology, meeting different environmental protection needs. Ammonia has a high octane number, and its anti-knock properties are superior to traditional fuels, thus supporting high compression ratio combustion, with a theoretical thermal efficiency approaching that of diesel engines.

[0003] However, ammonia typically cannot burn independently in engine cylinders and needs to be blended with other fuels (such as diesel, hydrogen, and dimethyl ether), with ammonia accounting for over 90% of the energy. One of the challenges in applying ammonia engines to vehicles, ships, or stationary power generation lies in the design and control of the ammonia supply system.

[0004] Chinese invention patent application number 202111500929.7 discloses an ammonia fuel engine supply system, including a liquid ammonia supply passage and an ignition gas supply passage. The liquid ammonia supply passage includes a liquid ammonia electronic injection valve, a high-pressure common rail, a two-stage turbocharger, and a first-stage turbocharger. The ignition gas supply passage includes an ammonia storage tank, an ignition gas assembly unit, an engine, and a solenoid valve. This application can adjust the temperature and pressure of the ignition gas according to the engine load, adaptively adjusting the engine to the optimal combustion condition. Furthermore, the high-temperature, high-pressure ignition gas can activate the ammonia fuel in the cylinder, improving the combustion characteristics of ammonia and reducing the high compression ratio, high intake pressure, and high temperature combustion conditions required by the engine. However, this ammonia fuel engine supply system has a relatively simple structure and poor automation control capabilities. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide an ammonia supply system for an ammonia engine.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: an ammonia supply system for an ammonia engine, comprising:

[0007] Liquid ammonia tank;

[0008] A booster circuit assembly; the booster circuit assembly includes a booster circuit water bath heater connected to the liquid ammonia tank via a first pipe, a first ammonia filter connected to the booster circuit water bath heater via a second pipe, a third pipe with one end connected to the first ammonia filter and the other end connected to the liquid ammonia tank, a first solenoid valve installed on the first pipe, an ammonia booster pump installed on the third pipe, and a check valve installed on the third pipe and located downstream of the ammonia booster pump;

[0009] The injection circuit assembly includes an injection path water bath heater connected to the liquid ammonia tank via a fourth pipe, a second solenoid valve installed on the fourth pipe, a fifth pipe with one end connected to the injection path water bath heater and the other end connected to the ammonia injection assembly, a second ammonia filter installed on the fifth pipe, and a pressure reducing valve installed on the fifth pipe and located between the second ammonia filter and the injection path water bath heater.

[0010] Ideally, it also includes:

[0011] An ammonia venting assembly includes a venting branch pipe connected at one end to the third pipeline, a safety valve installed on the venting branch pipe, and a dissolved water tank connected to the other end of the venting branch pipe and having a discharge outlet.

[0012] Furthermore, the booster circuit assembly also includes a first manual shut-off valve installed on the first pipeline and located upstream of the first solenoid valve, and a second manual shut-off valve installed on the third pipeline and located downstream of the check valve.

[0013] Furthermore, the injection circuit assembly also includes a third manual shut-off valve mounted on the fourth pipe and located upstream of the second solenoid valve.

[0014] Ideally, it also includes:

[0015] An engine coolant circuit assembly includes a coolant outlet pipe connected to the ammonia engine at one end, a third solenoid valve installed on the coolant outlet pipe, a first three-way valve connected to the other end of the coolant outlet pipe and connected to the boost circuit water bath heater and the injection circuit water bath heater respectively through two coolant inlet pipes, a second three-way valve connected to the boost circuit water bath heater and the injection circuit water bath heater respectively through two coolant return pipes, and a coolant return pipe connected to the second three-way valve and connected to the ammonia engine.

[0016] Another object of the present invention is to provide a method for controlling the ammonia supply of an ammonia engine, which is based on the above-mentioned ammonia supply system for an ammonia engine.

[0017] Optimally, it includes the following steps in no particular order:

[0018] (a) Controlling the ammonia supply to the booster circuit via the booster circuit assembly;

[0019] (b) Controlling the ammonia supply to the injection circuit via the injection circuit assembly.

[0020] Further, step (a) includes the following steps:

[0021] (a1) The liquid ammonia must first pass through the first manual shut-off valve, and the liquid ammonia can flow out only after the first manual shut-off valve is opened.

[0022] (a2) The ECU controls the opening or closing of the first solenoid valve and the third solenoid valve according to the pressure and coolant temperature parameters in the liquid ammonia tank; when the first solenoid valve is open, liquid ammonia enters the booster circuit water bath heater to absorb heat and vaporize into ammonia gas; the heat source of the booster circuit water bath heater comes from the engine coolant, and whether the coolant enters the booster circuit water bath heater is controlled by the third solenoid valve.

[0023] (a3) The ammonia gas vaporized by the water bath heater of the booster circuit passes through the first ammonia gas filter to remove impurities from the ammonia gas; the ammonia gas is then boosted by the ammonia gas booster pump and passes through the check valve to prevent ammonia gas backflow.

[0024] (a4) Allow the ammonia gas to return to the liquid ammonia tank after passing through the second manual shut-off valve.

[0025] Furthermore, step (b) includes the following steps:

[0026] (b1) The liquid ammonia is first passed through the third manual shut-off valve, and the liquid ammonia can flow out only after the third manual shut-off valve is opened;

[0027] (b2) The ECU controls the opening and closing of the second solenoid valve according to the engine operating conditions and coolant temperature parameters; when the second solenoid valve is open, liquid ammonia enters the injection circuit water bath heater to absorb heat and vaporize into ammonia gas; the heat source of the injection circuit water bath heater comes from the engine coolant, and whether the coolant enters the injection circuit water bath heater is controlled by the third solenoid valve.

[0028] (b3) The ammonia gas vaporized by the water bath heater of the jet path passes through the pressure reducing valve, and after pressure reduction, it passes through the second ammonia gas filter to filter out impurities in the ammonia gas, and then enters the ammonia gas injection assembly.

[0029] (b4) The ECU controls the ammonia injection according to the engine operating conditions. After passing through the ammonia-air mixer, the ammonia enters the engine intake manifold and enters the engine cylinder for combustion together with fresh air.

[0030] Furthermore, in step (b3), the ammonia gas is reduced to 5-8 bar by the pressure reducing valve.

[0031] Due to the application of the above technical solutions, the present invention has the following advantages compared with the prior art: The ammonia supply system of the ammonia engine of the present invention, by adopting the combination of the booster circuit assembly and the injection circuit assembly, can realize the design of an ammonia supply system that integrates the functions of liquid storage to gas injection (i.e., the storage, vaporization, depressurization, injection and boosting of ammonia). It can be used for the supply and regulation of ammonia gas in small and medium-sized ammonia fuel engines and can be installed in the vehicle or placed in the work site. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the ammonia engine of the present invention;

[0033] Figure 2 This is a schematic diagram of the ammonia supply system for the ammonia engine of the present invention;

[0034] Figure 3 This is an overall framework diagram of the first relay control module;

[0035] Figure 4 This is the control logic block diagram for the first relay;

[0036] Figure 5 This is an overall framework diagram of the second relay control module;

[0037] Figure 6 This is the control logic block diagram for the second relay;

[0038] Figure 7 This is the overall framework diagram of the third relay control module;

[0039] Figure 8 This is the control logic block diagram for the third relay. Detailed Implementation

[0040] The present invention will be further described below with reference to the embodiments shown in the accompanying drawings.

[0041] like Figure 1 and Figure 2 The ammonia supply system for the ammonia engine shown mainly includes a liquid ammonia tank 1, a booster circuit assembly 2, an injection circuit assembly 3, an ammonia venting assembly 4, and an engine coolant circuit assembly 5, etc. (Note) Figure 1 and Figure 2 They are connected together, in order to... Figure 1 and Figure 2 (Use wavy lines to separate them only when they are clearly displayed).

[0042] The volume of the liquid ammonia tank 1 can be adjusted according to the vehicle space and fuel requirements, typically ranging from 400 to 1200L. The tank contains liquid ammonia, and the pressure inside the tank will change with the ambient temperature. Its typical value is about 10 bar at 25°C.

[0043] The booster circuit assembly 2 includes a booster water bath heater 21 connected to the liquid ammonia tank 1 via a first pipe 20, a first ammonia filter 23 connected to the booster water bath heater 21 via a second pipe 22, a third pipe 24 connected at one end to the first ammonia filter 23 and at the other end to the liquid ammonia tank 1, a first solenoid valve 25 installed on the first pipe 20, an ammonia booster pump 27 installed on the third pipe 24, and a check valve 28 installed on the third pipe 24 and located downstream of the ammonia booster pump 27. In this embodiment, the booster circuit assembly 2 also includes a first manual shut-off valve 26 installed on the first pipe 20 and located upstream of the first solenoid valve 25, and a second manual shut-off valve 29 installed on the third pipe 24 and located downstream of the check valve 28 (the definitions of upstream and downstream in this application are based on the flow direction of liquid ammonia or ammonia gas, and the same applies below).

[0044] The injection circuit assembly 3 includes an injection path water bath heater 34 connected to the liquid ammonia tank 1 via a fourth pipe 31, a second solenoid valve 32 installed on the fourth pipe 31, and an ammonia injection assembly (see [link]). Figure 1 The fifth pipe 37 (which can be conventionally available), the second ammonia filter 36 installed on the fifth pipe 37, and the pressure reducing valve 35 installed on the fifth pipe 37 and located between the second ammonia filter 36 and the jet circuit water bath heater 34 can all be used. In this embodiment, the jet circuit assembly 3 also includes a third manual shut-off valve 33 installed on the fourth pipe 31 and located upstream of the second solenoid valve 32.

[0045] The ammonia venting assembly 4 includes a venting branch pipe 41 connected to the third pipe 24 at one end, a safety valve 42 installed on the venting branch pipe 41, and a dissolved water tank 43 connected to the other end of the venting branch pipe 41 and having a discharge outlet. The connection between the venting branch pipe 41 and the third pipe 24 is located downstream of the second manual shut-off valve 29, which enables the absorption of ammonia and prevents excessive ammonia pressure from overflowing and polluting the environment.

[0046] The engine coolant circuit assembly 5 is connected to the ammonia engine, allowing for coolant cooling through coolant circulation. Specifically, it includes: a coolant outlet pipe connected to the ammonia engine at one end; a third solenoid valve 51 mounted on the coolant outlet pipe; a first three-way valve 52 connected to the other end of the coolant outlet pipe and via two coolant inlet pipes respectively connected to the booster circuit water bath heater 21 and the injection circuit water bath heater 34; a second three-way valve 53 connected to the booster circuit water bath heater 21 and the injection circuit water bath heater 34 via two coolant return pipes respectively; and a coolant return pipe connected to the second three-way valve 53 and the ammonia engine. The heated engine coolant can then be used to heat the liquid ammonia, thereby improving the engine's thermal efficiency.

[0047] The method for controlling the ammonia supply of an ammonia engine, based on the aforementioned ammonia supply system, includes the following steps in no particular order:

[0048] (a) Controlling the ammonia supply to the booster circuit via the booster circuit assembly 2; specifically, step (a) includes the following steps:

[0049] (a1) The liquid ammonia must first pass through the first manual shut-off valve 26, and the liquid ammonia can flow out only after the first manual shut-off valve 26 is opened;

[0050] (a2) The ECU controls the opening or closing of the first solenoid valve 25 and the third solenoid valve 51 based on parameters such as the pressure inside the liquid ammonia tank 1 and the coolant temperature. When the first solenoid valve 25 is opened, liquid ammonia enters the boost circuit water bath heater 21 to absorb heat and vaporize into ammonia gas. The heat source of the boost circuit water bath heater 21 comes from the engine coolant. Whether the coolant enters the boost circuit water bath heater 21 is controlled by the third solenoid valve 51.

[0051] (a3) The ammonia gas vaporized by the booster water bath heater 21 then passes through the first ammonia gas filter 23 to remove impurities from the ammonia gas; the ammonia gas is then boosted by the ammonia gas booster pump 27 and passes through the check valve 28 to prevent ammonia gas backflow.

[0052] (a4) Allow the ammonia gas to return to the liquid ammonia tank 1 after passing through the second manual shut-off valve 29.

[0053] (b) Controlling the ammonia supply to the injection circuit via injection circuit assembly 3; specifically, step (b) includes the following steps:

[0054] (b1) The liquid ammonia must first pass through the third manual shut-off valve 33, and the liquid ammonia can flow out only after the third manual shut-off valve 33 is opened.

[0055] (b2) The ECU controls the opening and closing of the second solenoid valve 32 according to parameters such as engine operating conditions and coolant temperature. When the second solenoid valve 32 is open, liquid ammonia enters the injection circuit water bath heater 34 to absorb heat and vaporize into ammonia gas. The heat source of the injection circuit water bath heater 34 comes from the engine coolant. Whether the coolant enters the injection circuit water bath heater 34 is controlled by the third solenoid valve 51.

[0056] (b3) The ammonia gas vaporized by the water bath heater 34 of the jet path then passes through the pressure reducing valve 35 (reduced to 5-8 bar, preferably 6 bar), and after pressure reduction, it passes through the second ammonia gas filter 36 to filter out impurities in the ammonia gas, and then enters the ammonia gas injection assembly.

[0057] (b4) The ECU controls the ammonia injection according to the engine operating conditions. After passing through the ammonia-air mixer, the ammonia enters the engine intake manifold and enters the engine cylinder for combustion together with fresh air.

[0058] To further improve the control accuracy of ammonia supply to the aforementioned ammonia engine, the following functional controls are also implemented.

[0059] This application determines whether the third solenoid valve 51 needs to operate based on water temperature and rotation speed, without directly controlling the third solenoid valve 51; instead, it selects whether the third solenoid valve 51 is energized through the first relay. The control variables are shown in Tables 1 to 3. The first relay operates every 50ms, primarily determining whether the third solenoid valve 51 needs to operate based on water temperature and rotation speed. (See [reference needed]). Figure 3 and Figure 4 The processing flow is as follows:

[0060] The main switch CTV_Actv_C is set to 1 to enable the control of the third solenoid valve 51.

[0061] First relay activation condition determination:

[0062] (1) The water temperature exceeds 40℃ (this threshold is calibrated by CTV_OnECTThres_C);

[0063] (2) The rotation speed exceeds 400 rpm (this threshold is calibrated by CTV_OnESPDThres_C); if the above conditions are met, the first relay will output 1.

[0064] First relay disconnection condition judgment:

[0065] (1) The water temperature is below 35℃ (this threshold is calibrated by CTV_OnECTThres_C-CTV_OffECTHys_C);

[0066] (2) The engine speed is below 300 rpm (this threshold is calibrated by CTV_OnESPDThres_C-CTV_OffESPDHys_C);

[0067] If any of the above conditions are met, the first relay will output a 0.

[0068] Table 1 List of input variables for the first relay control

[0069]

[0070] Table 2 List of output variables for the first relay control

[0071] variable name type Variable Description unit OUT_CoolantTankVlv_Flg bool First relay activation indicator /

[0072] Table 3 List of calibration variables for the first relay control

[0073]

[0074]

[0075] The system also determines whether the second solenoid valve 32 needs to operate based on water temperature and rotation speed. Instead of directly controlling the second solenoid valve 32, it uses a second relay to select whether the second solenoid valve 32 is energized. The control variables are shown in Tables 4 to 6. The second relay operates every 50ms, primarily determining whether the second solenoid valve 32 needs to operate based on water temperature and rotation speed. (See [reference needed]). Figure 5 and Figure 6 The processing flow is as follows:

[0076] The main switch FTV_Actv_C is set to 1 to enable the control of the second solenoid valve 32.

[0077] Second relay activation condition determination:

[0078] (1) The water temperature exceeds 45℃ (this threshold is calibrated by FTV_OnECTThres_C);

[0079] (2) Rotation speed exceeds 400 rpm (this threshold is calibrated by FTV_OnESPDThres_C);

[0080] (3) After the third solenoid valve 51 is opened for 100 seconds (this threshold is calibrated by FTV_CtvActvDlyTim_C), if the above conditions are met at the same time, the second relay will output 1.

[0081] Second relay disconnection condition judgment:

[0082] (1) The water temperature is below 35℃ (this threshold is calibrated by FTV_OnECTThres_C-FTV_OffECTHys_C);

[0083] (2) The engine speed is below 300 rpm (this threshold is determined by FTV_OnESPDThres_C-FTV_OffESPDHys_C);

[0084] (3) The third solenoid valve 51 is closed;

[0085] If any of the above conditions are met, the second relay's activation flag will output 0.

[0086] Table 4 List of input variables for the second relay control

[0087]

[0088] Table 5 List of Second Relay Control Output Variables

[0089] variable name type Variable Description unit OUT_FuelTankVlv_Flg bool Second relay activation indicator /

[0090] Table 6 List of Calibration Variables for the Second Relay Control

[0091]

[0092] The system also determines whether the first solenoid valve 25 needs to operate based on water temperature, rotation speed, and pressure inside the liquid ammonia tank 1. Instead of directly controlling the first solenoid valve 25, a third relay is used to select whether the first solenoid valve 25 is energized. The control variables are shown in Tables 7 to 9. The third relay operates every 50ms, primarily determining whether the first solenoid valve 25 needs to operate based on water temperature, rotation speed, and pressure inside the liquid ammonia tank. (See [reference needed]). Figure 7 and Figure 8 The processing flow is as follows:

[0093] The enable switch BGTV_Actv_C is set to 1, which activates the control of the first solenoid valve 25.

[0094] Third relay activation condition determination:

[0095] (1) The water temperature exceeds 45℃ (this threshold is calibrated by FTV_OnECTThres_C);

[0096] (2) Rotation speed exceeds 400 rpm (this threshold is calibrated by FTV_OnESPDThres_C);

[0097] (3) The pressure inside the liquid ammonia tank is lower than 100 kPa (the threshold is calibrated by BGTV_OffPNH3TankThres_C); if the above conditions are met, the relay will output 1.

[0098] Third relay disconnection condition judgment:

[0099] (1) The water temperature is below 35℃ (this threshold is calibrated by FTV_OnECTThres_C-FTV_OffECTHys_C);

[0100] (2) The engine speed is below 300 rpm (this threshold is determined by FTV_OnESPDThres_C-FTV_OffESPDHys_C);

[0101] (3) The pressure inside the liquid ammonia tank is higher than 140 kPa (threshold is determined by BGTV_OffPNH3TankThres_C+).

[0102] BGTV_PNH3TankHys_C calibration);

[0103] If any of the above conditions are met, the third relay will activate and output a 0.

[0104] Table 7 List of input variables for the third relay control

[0105]

[0106] Table 8 List of Third Relay Control Output Variables

[0107] variable name type Variable Description unit OUT_NH3TankVlv_Flg bool Third relay activation indicator / NH3_PumpEn_Flg bool Ammonia enables effective sites / NH3_TankEn_Flg bool Ammonia enables potential / NBP_RefSpd_Value int16_t Target speed of self-boosting pump rpm

[0108] Table 9 List of Calibration Variables for the Third Relay Control

[0109]

[0110] The ammonia booster pump 27 is a self-boosting pump, which facilitates the control of the NBP1 message output of the self-boosting pump. After the third relay is energized, after a 100s delay (the delay time is calibrated by J1939_BGTVDlyTim_C), the ammonia enable bit and ammonia enable valid bit of the NBP1 message become 1, and the target speed of the self-boosting pump is sent starting from the 2nd and 3rd bytes of the message.

[0111] The target speed of the booster pump is obtained by looking up a table based on the pressure inside the liquid ammonia tank received in the message. The target speed lookup table is calibrated as NH3_PumpRefSpd_Crv. The speed value obtained from the lookup table needs to be filtered by a slope, with an upper limit of 5000 rpm / s for the slope. After the third relay is disconnected, the ammonia enable bit and the ammonia enable valid bit sent in the NBP1 message become 0, and the target speed of the booster pump is gradually filtered to 0.

[0112] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An ammonia supply system for an ammonia engine, characterized in that it comprises It comprises: a liquid ammonia tank (1); a pressurization circuit assembly (2); the pressurization circuit assembly (2) comprises a pressurization circuit water bath heater (21) communicated with the liquid ammonia tank (1) through a first pipeline (20), a first ammonia gas filter (23) communicated with the pressurization circuit water bath heater (21) through a second pipeline (22), a third pipeline (24) having one end communicated with the first ammonia gas filter (23) and the other end communicated with the liquid ammonia tank (1), a first electromagnetic valve (25) installed on the first pipeline (20), an ammonia gas pressurization pump (27) installed on the third pipeline (24), and a check valve (28) installed on the third pipeline (24) and located downstream of the ammonia gas pressurization pump (27); the pressurization circuit assembly (2) further comprises a first manual cut-off valve (26) installed on the first pipeline (20) and located upstream of the first electromagnetic valve (25), and a second manual cut-off valve (29) installed on the third pipeline (24) and located downstream of the check valve (28); a spray circuit assembly (3); the spray circuit assembly (3) comprises a spray circuit water bath heater (34) communicated with the liquid ammonia tank (1) through a fourth pipeline (31), a second electromagnetic valve (32) installed on the fourth pipeline (31), a fifth pipeline (37) having one end communicated with the spray circuit water bath heater (34) and the other end connected with an ammonia gas spray assembly, a second ammonia gas filter (36) installed on the fifth pipeline (37), and a pressure reducing valve (35) installed on the fifth pipeline (37) and located between the second ammonia gas filter (36) and the spray circuit water bath heater (34); an ammonia gas exhaust assembly (4); the ammonia gas exhaust assembly (4) comprises an exhaust branch pipe (41) having one end communicated with the third pipeline (24), a safety valve (42) installed on the exhaust branch pipe (41), and a dissolving water tank (43) having an exhaust port and connected with the other end of the exhaust branch pipe (41).

2. The ammonia supply system of the ammonia engine according to claim 1, characterized by: The spray circuit assembly (3) further comprises a third manual cut-off valve (33) installed on the fourth pipeline (31) and located upstream of the second electromagnetic valve (32).

3. The ammonia supply system of the ammonia engine according to claim 2, characterized by It further comprises: an engine coolant circuit assembly (5); the engine coolant circuit assembly (5) comprises a coolant outflow pipe having one end communicated with the ammonia engine, a third electromagnetic valve (51) installed on the coolant outflow pipe, a first three-way valve (52) communicated with the other end of the coolant outflow pipe and communicated with the pressurization circuit water bath heater (21) and the spray circuit water bath heater (34) through two coolant inflow pipes, a second three-way valve (53) communicated with the second three-way valve (53) and communicated with the ammonia engine through two coolant return pipes.

4. A control method of ammonia supply of an ammonia engine, characterized by: The control method is applied to the ammonia engine ammonia supply system as claimed in claim 3.

5. The control method of the ammonia supply of the ammonia engine according to claim 4, characterized by, The control method comprises the following steps in no particular order: (a) Control of pressurized circuit ammonia supply through the pressurized circuit assembly (2); (b) Control of injection circuit ammonia supply through the injection circuit assembly (3).

6. The control method of the ammonia supply of the ammonia engine according to claim 5, characterized by, Step (a) comprises the following steps: (a1) Liquid ammonia first passes through the first manual stop valve (26), which opens to allow liquid ammonia to flow out; (a2) The ECU controls the opening or closing of the first electromagnetic valve (25) and the third electromagnetic valve (51) according to the pressure in the liquid ammonia tank (1) and the coolant temperature parameters; when the first electromagnetic valve (25) is opened, liquid ammonia enters the pressurized water bath heater (21) to absorb heat and vaporize into ammonia gas; the heat source of the pressurized water bath heater (21) comes from the engine coolant, and whether the coolant enters the pressurized water bath heater (21) is controlled by the third electromagnetic valve (51); (a3) The ammonia gas vaporized by the pressurized water bath heater (21) passes through the first ammonia gas filter (23) to remove impurities in the ammonia gas; the ammonia gas is then pressurized by the ammonia gas pressurizing pump (27) and passes through the check valve (28) to prevent backflow of ammonia gas; (a4) The ammonia gas passes through the second manual stop valve (29) and returns to the liquid ammonia tank (1).

7. The control method of the ammonia supply of the ammonia engine according to claim 5, characterized by, Step (b) comprises the following steps: (b1) Liquid ammonia first passes through the third manual stop valve (33), which opens to allow liquid ammonia to flow out; (b2) The ECU controls the opening and closing of the second electromagnetic valve (32) according to the engine operating conditions and coolant temperature parameters; when the second electromagnetic valve (32) is opened, liquid ammonia enters the injection water bath heater (34) to absorb heat and vaporize into ammonia gas; the heat source of the injection water bath heater (34) comes from the engine coolant, and whether the coolant enters the injection water bath heater (34) is controlled by the third electromagnetic valve (51); (b3) The ammonia gas vaporized by the injection water bath heater (34) passes through the pressure reducing valve (35), is reduced in pressure, passes through the second ammonia gas filter (36) to remove impurities in the ammonia gas, and then enters the ammonia gas injection assembly; (b4) The ECU controls ammonia injection according to engine operating conditions, and the ammonia gas enters the engine intake manifold after passing through the ammonia-air mixer, and enters the engine cylinder together with fresh air for combustion.

8. The control method of the ammonia supply of the ammonia engine according to claim 7, characterized by: In step (b3), the ammonia gas is reduced in pressure to 5-8 bar by the pressure reducing valve (35).

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