Dual-valve coordinated control of hydrogen-assisted combustion liquid ammonia-diesel dual-fuel injection system and method

Abstract

The present invention provides a dual-valve coordinated control hydrogen combustion liquid ammonia diesel dual fuel injection system and its control method, relating to the field of engine technology, the fuel common rail pipe is respectively connected to the electronically controlled injector and the fuel tank, the liquid ammonia common rail pipe is respectively connected to the liquid ammonia injector, the inlet and outlet ammonia system, the inlet and outlet ammonia system is arranged with an ammonia inlet pipe and ammonia return pipe, the pump ammonia system includes a liquid ammonia storage diverter, a low-pressure pump, a high-pressure pump, the shunt system includes a storage tank, an ammonia inlet control valve, a safety valve, an ammonia outlet control valve, the outlet of the liquid ammonia storage tank is sequentially connected to the low-pressure pump, the high-pressure pump, the liquid ammonia storage diverter, the storage tank, the ammonia inlet control valve, the ammonia inlet control valve is connected to the liquid ammonia common rail pipe through the ammonia inlet pipe, the inlet of the liquid ammonia storage tank is sequentially connected to the return ammonia control valve and the safety valve, the safety valve is connected to the liquid ammonia injector through the return ammonia pipe, and the liquid ammonia storage tank is respectively connected to the hydrogen storage tank and the nitrogen storage tank. The present invention provides an implementable path for liquid ammonia to be used in an engine as a fuel.

Description

[0001] This application is a divisional application of the parent patent application entitled "Dual-valve coordinated control of hydrogen-assisted combustion liquid ammonia-diesel dual fuel injection system"; the parent application number is:

[0002] CN202111374145.4; the application date of the parent application is: 2021.11.19. Technical Field

[0003] The present invention relates to the field of engine technology, and in particular to a dual-valve coordinated control hydrogen-assisted combustion liquid ammonia-diesel dual-fuel injection system and a control method thereof. Background Art

[0004] Current power systems under development face difficulties in addressing high carbon emissions due to the limitations of traditional fuels, while global warming presents a global challenge that humanity must address. Therefore, the development of new low-carbon fuels is crucial. Hydrogen and ammonia, with their abundant hydrogen content, are globally recognized as important options for future clean energy. Currently, there is considerable activity in the development and application of hydrogen, a key fuel for fuel cells. However, hydrogen storage is extremely difficult, and its stability and risk are high. Its use as an engine fuel also presents difficult-to-solve issues such as detonation. Therefore, ammonia fuel holds significant development potential. As a good hydrogen carrier, it is easy to store and less prone to explosion. As an engine fuel, it can be blended and ignited to mitigate ignition difficulties, making it a key direction for future low-carbon fuel development.

[0005] Since ammonia burns as a single fuel, its high auto-ignition temperature, low calorific value, and low flame propagation speed have greatly affected its application in engines. Ammonia dual-fuel combustion not only effectively solves the problems encountered when burning pure ammonia fuel, but also facilitates the production of corresponding prototypes by improving the fuel adaptability based on existing engines. Due to the slow combustion rate of ammonia, the premixed combustion method may result in low thermal efficiency of ammonia engines. In addition, ammonia has a high auto-ignition temperature, making it difficult to directly compress and ignite, requiring other fuels for ignition. The hydrogen blending method can further increase the flame propagation speed and can be used in both low-pressure and high-pressure dual-fuel engines. However, hydrogen blending will increase the difficulty of storage, the complexity of the injection system, the price of the fuel, and it is difficult to guarantee safety. Summary of the Invention

[0006] The object of the present invention is to provide a dual-valve coordinated control hydrogen-assisted combustion liquid ammonia-diesel dual-fuel injection system and a control method thereof, using liquid ammonia as fuel in an engine.

[0007] The present invention provides the following technical solutions:

[0008] The present invention provides a dual-valve coordinated control hydrogen-assisted combustion liquid ammonia-diesel dual-fuel injection system, comprising an electronically controlled fuel injector, a liquid ammonia injector, a liquid ammonia common rail pipe, a fuel common rail pipe, a fuel tank, a liquid ammonia storage tank, an ammonia pump system, a diversion system and an ammonia inlet and outlet system, wherein the fuel common rail pipe is respectively connected to the electronically controlled fuel injector and the fuel tank, the liquid ammonia common rail pipe is respectively connected to the liquid ammonia injector and the ammonia inlet and outlet system, an ammonia inlet pipe and an ammonia return pipe are arranged in the ammonia inlet and outlet system, the ammonia pump system comprises a liquid ammonia storage diverter, a low-pressure pump and a high-pressure pump, the diversion system comprises a storage tank, an ammonia inlet control valve, a safety valve and an ammonia outlet control valve, the outlet of the liquid ammonia storage tank is sequentially connected to the low-pressure pump, the high-pressure pump, the liquid ammonia storage diverter, the storage tank and the ammonia inlet control valve, The ammonia inlet control valve is connected to the liquid ammonia common rail pipe through the ammonia inlet pipe, the inlet of the liquid ammonia storage tank is connected to the ammonia return control valve and the safety valve in sequence, the safety valve is connected to the liquid ammonia injector through the ammonia return pipe, and the liquid ammonia storage tank is connected to the hydrogen storage tank and the nitrogen storage tank respectively; the electronically controlled injector includes an injector body, a boost module, a pressure accumulator resonance current limiting module, a pressure balance electromagnetic control actuator and a phase change controllable super atomizing nozzle module, a one-way ammonia inlet and an ammonia inlet pipeline are provided on the injector body, the boost module, the pressure accumulator resonance current limiting module, and the pressure balance electromagnetic control actuator are located in the injector body and are arranged in sequence from top to bottom, and the phase change controllable super atomizing nozzle module is located below the pressure balance electromagnetic control actuator.

[0009] Preferably, the boost module includes a magnetic yoke, a main and auxiliary magnetic poles, a boost piston, an armature, a limit block, a double-sealed valve stem, an upper valve stem seat and a lower valve stem seat, the armature is sleeved on the top of the double-sealed valve stem, a reset spring is arranged between the magnetic yoke and the armature, the main and auxiliary magnetic poles are arranged on the outside of the reset spring, the main and auxiliary magnetic poles are wound with coils, the middle part of the double-sealed valve stem is located in the upper valve stem seat, the bottom of the double-sealed valve stem is located in the lower valve stem seat, and the middle part of the double-sealed valve stem is sleeved with a valve stem reset spring A double sealing protrusion is provided between the middle and the bottom of the double sealing valve stem, and sealing surfaces are provided on the surfaces corresponding to the upper valve stem seat, the lower valve stem seat and the double sealing valve stem. The booster piston is located below the lower valve stem seat, and a booster piston return spring is sleeved on the outside of the booster piston. A communicating ammonia return channel and an intermediate pipeline are provided in the upper valve stem seat, and an ammonia inlet channel is provided in the lower valve stem seat. The space where the double sealing protrusion is located in the lower valve stem seat is a communicating space, and the communicating space is communicated with the intermediate pipeline.

[0010] Preferably, the pressure storage resonance current limiting module includes a resonance block, a resonance middle block, a diamond sealing block, a current limiting piston and a valve seat. A pressure storage chamber is arranged in the injector body below the boosting piston, and a liquid cooling pipe inlet is arranged on the injector body. The liquid cooling pipe inlet is connected to the pressure storage chamber. The resonance block, the resonance middle block, the diamond sealing block and the valve seat are arranged in sequence below the pressure storage chamber. The current limiting piston is arranged in the valve seat, and the middle block return spring is arranged in the resonance middle block. The bottom of the resonance middle block is respectively provided with an oil inlet hole and a resonance block ammonia inlet throttling hole. The diamond sealing block is located above the current limiting piston, and an middle hole is arranged in the current limiting piston. A current limiting piston return spring is arranged below the current limiting piston, and a storage chamber is arranged below the current limiting piston return spring.

[0011] Preferably, the resonance block is respectively provided with a No. 1 ammonia inlet, a No. 2 ammonia inlet, a No. 1 ammonia inlet cavity, a No. 2 ammonia inlet cavity, a No. 1 ammonia outlet and a No. 2 ammonia outlet, the No. 1 ammonia inlet cavity is respectively connected to the No. 1 ammonia inlet and the No. 1 ammonia outlet, the No. 2 ammonia inlet cavity is respectively connected to the No. 2 ammonia inlet and the No. 2 ammonia outlet, the No. 1 ammonia inlet cavity is communicated with the No. 2 ammonia inlet cavity through a connecting hole, the No. 1 ammonia inlet cavity is connected to the No. 1 ammonia inlet through the No. 1 ammonia inlet throttle hole, and the No. 1 ammonia inlet cavity is connected to the pressure accumulator through the No. 2 ammonia inlet throttle hole.

[0012] Preferably, the pressure-balanced electromagnetic control actuator includes piezoelectric main and secondary magnetic poles, a piezoelectric armature and a balancing valve stem. The piezoelectric main and secondary magnetic poles are located in the injector body. A piezoelectric block and an intermediate block are sequentially arranged below the injector body. A low-pressure chamber is arranged at the upper end of the piezoelectric block. The piezoelectric armature is arranged in the low-pressure chamber. The piezoelectric armature is located below the piezoelectric main and secondary magnetic poles. The balancing valve stem passes through the piezoelectric armature. The upper end of the balancing valve stem is located in the piezoelectric main and secondary magnetic poles. The lower end of the balancing valve stem is located in the piezoelectric block. The balancing valve stem located in the piezoelectric main and secondary magnetic poles is sleeved with a balancing valve stem reset spring. A return oil chamber and an oil inlet throttling hole are arranged in the intermediate block. The cavity below the balancing valve stem is connected to the return oil chamber through the return oil throttling hole.

[0013] Preferably, the phase change controllable super atomizing nozzle module includes a nozzle body, a valve seat, a needle valve body and a self-regulating valve block, the valve seat is located in the nozzle body, the needle valve body is located in the valve seat, the head of the needle valve body is located in the self-regulating valve block and forms a control chamber with it, the self-regulating valve block is located below the intermediate block, the control chamber is connected to the return oil chamber, a needle valve body reset spring is arranged between the middle part of the needle valve body and the self-regulating valve block, an ammonia inlet pipeline is formed between the needle valve body, the self-regulating valve block and the valve seat, a refrigerant inlet is formed between the valve seat and the nozzle body, an injection channel is formed between the bottom of the needle valve body and the bottom of the valve seat, and an ammonia tank is formed between the injection channel and the ammonia inlet pipeline.

[0014] The present invention also provides a control method for the above-mentioned dual-valve coordinated control hydrogen-assisted combustion liquid ammonia-diesel dual-fuel injection system, including a non-boost control mode and a boost control mode;

[0015] No-boost control mode: The boost module is de-energized, the ammonia inlet channel is sealed, and the boost piston is in a reset state under the action of the spring preload. Ammonia fuel passes through the one-way ammonia inlet and is stored in the pressure accumulator chamber. The flow-limiting piston and the diamond-shaped sealing block move downward as a whole. When the pressure-balanced electromagnetic control actuator is energized, the piezoelectric armature overcomes the piezoelectric spring preload and moves upward. The fuel in the control chamber flows back to the low-pressure chamber through the oil return throttle hole. When the combined force of the pressure in the control chamber and the elastic force of the needle valve body return spring is less than the upward hydraulic pressure in the ammonia tank, the needle valve body lifts upward. When the pressure-balanced electromagnetic control actuator is partially de-energized, the piezoelectric armature moves downward, driving the balancing valve stem downward to achieve sealing. The control chamber is re-pressurized through the oil inlet throttle hole. When the combined force of the pressure in the control chamber and the elastic force of the needle valve body return spring is greater than the upward hydraulic pressure in the ammonia tank, the needle valve body re-seates, the injection system stops spraying, and the flow-limiting piston and the diamond-shaped sealing block return to their initial positions as a whole.

[0016] Boost control mode: When the boost module is energized, the armature moves upward, and at the same time drives the double-seal valve stem upward, opening the ammonia inlet channel and closing the ammonia return channel. The liquid ammonia gathers on the upper surface of the boost piston, and the boost piston moves downward. When the pressure-balanced electromagnetic control actuator is energized, the piezoelectric armature overcomes the preload force of the piezoelectric return spring and moves upward. The fuel in the control chamber flows back to the low-pressure chamber through the return oil throttle hole. When the combined force formed by the pressure in the control chamber and the elastic force of the needle valve body return spring is less than the upward liquid pressure in the ammonia tank, the needle valve body lifts up. When the pressure-balanced electromagnetic control actuator is partially de-energized, the piezoelectric armature moves downward, re-sealing the return oil circuit and driving the balancing valve stem downward to achieve sealing. The control chamber is re-pressurized through the oil inlet throttle hole. When the combined force formed by the pressure in the control chamber and the elastic force of the needle valve body return spring is greater than the upward liquid pressure in the ammonia tank, the needle valve body re-seates and the injection system stops injecting.

[0017] Compared with the prior art, the present invention has achieved the following technical effects:

[0018] 1. Using low-pressure storage tanks as a medium to achieve safe storage of liquid ammonia. The parallel connection of liquid ammonia hydrogen production reaction mechanisms provides a hydrogen supply source for fuel cells and engines, as well as ammonia fuel for engines, greatly improving storage efficiency.

[0019] 2. The invention of a dual-fuel supply system, with a diesel-ignition and hydrogen-assisted combustion mode, solves the problem of difficult combustion and insufficient reaction of ammonia fuel;

[0020] 3. The liquid ammonia and hydrogen supply system uses a double-layer high-pressure oil pipe and a double-layer common rail pipe structure. At the same time, detection sensors and nitrogen purge devices are installed at the interlayer interface to ensure that the system can detect ammonia fuel leaks in time and achieve intrinsic safety;

[0021] 4. Since ammonia fuel has a higher anti-explosion property, a higher compression ratio (20:1) is used in the design of the cylinder and piston to increase thermal efficiency.

[0022] 5. The injection process is combined with thermal management design to adjust the pressure and temperature to control the phase change of ammonia fuel;

[0023] 6. The double-valve control method is adopted to realize the variable cycle of liquid ammonia injection process, making the injection amount and injection timing more accurate and flexible;

[0024] 7. A resonant block is used to adjust the pressure fluctuations in the system. By changing the phase of the pressure wave, adjusting the frequency of the fluctuations, and the corresponding relationship between the peaks and troughs, the pressure wave coupling process can be controlled. A flow limiter is also designed to prevent abnormal injection.

[0025] 8. The balanced valve control method uses a balanced force, which allows the valve to achieve a higher common rail pressure (250MPa) because the entire valve is immersed in high-pressure fuel and is subject to the balanced force. This reduces the mass of the valve components, thus reducing the electromagnetic force required and increasing the control response. This requires a smaller solenoid valve and armature, as well as a smaller spring preload. Furthermore, the balanced valve stem is not directly exposed to high-pressure impact, preventing the cavitation of traditional ball valves and increasing system reliability.

[0026] 9. The combined design of the intermediate block and the self-adjusting valve block solves the leakage problem of the traditional static block on the one hand, and on the other hand, the design of the self-adjusting valve block prevents the wear and leakage caused by the eccentricity of the needle valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0028] Figure 1 It is a structural schematic diagram of the present invention;

[0029] Figure 2 This is a schematic diagram of the overall structure of the liquid ammonia and hydrogen supply system;

[0030] Figure 3 This is a schematic diagram of the structure of a dual-valve coordinated control ammonia fuel injector;

[0031] Figure 4 It is a schematic diagram of the boost module structure;

[0032] Figure 5 This is a schematic diagram of the structure of the accumulator thermal management module;

[0033] Figure 6 Schematic diagram of the resonant block structure;

[0034] Figure 7 It is a schematic diagram of the structure of a pressure-balanced electromagnetic control actuator;

[0035] Figure 8 Schematic diagram of the phase change controllable super atomizing nozzle module structure;

[0036] Figure 9 This is an enlarged view of the dual-fuel cylinder structure;

[0037] Figure 10 Schematic diagram of the three-dimensional overall structure of the phase change controllable super atomizing nozzle module;

[0038] Figure 11 Schematic diagram of the three-dimensional cross-sectional structure of the phase change controllable super atomizing nozzle module. DETAILED DESCRIPTION

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

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

[0041] Combine Figure 1-11 , Figure 1 This is a schematic diagram of the overall structure of the present invention. The fuel supply system includes a fuel tank 7, a filter 6, a high-pressure oil pump 4 and motor, a return oil line 5, a fuel common rail 11, a flow limiter 12, high-pressure oil pipes 3 and 13, and an electronically controlled fuel injector 14. The right end of the fuel common rail 11 is connected to the high-pressure oil pump 4, filter 6, and fuel tank 7 respectively. The fuel common rail 11 has multiple hydraulic oil outlets, each of which is connected to a flow limiter 12 to ensure timely closure in abnormal operating conditions and minimize losses. The number of flow limiters 12 is determined by the number of cylinders in the internal combustion engine. The flow limiter 12 is connected to the electronically controlled fuel injector 14 via the high-pressure oil pipe 13. The electronically controlled fuel injector 14 is connected to the fuel tank 7 via the return oil line 5.

[0042] Figure 2This is a detailed schematic diagram of the liquid ammonia and hydrogen supply system, which mainly includes a liquid ammonia storage tank 24, a hydrogen storage tank 25, a nitrogen storage tank 23, an ammonia pumping system 22, a diversion system 21, an ammonia inlet and outlet system 19, an ammonia inlet pipe 17, an ammonia return pipe 18, a liquid ammonia common rail pipe 1, a liquid ammonia leak detection port 10, a double-layer high-pressure oil pipe 2, and a liquid ammonia injector 8. The ammonia pumping system 22 includes a liquid ammonia storage diverter 31, a low-pressure pump and motor 26, and a high-pressure pump and motor 27. The diversion system 21 includes a storage tank 32, an ammonia inlet control valve 33, a safety valve 38, and a return ammonia control valve 39. The outlet of the liquid ammonia storage tank 24 is connected in sequence to the low-pressure pump, the high-pressure pump, the liquid ammonia storage diverter 31, the storage tank 32, and the ammonia inlet control valve 33. A relief valve 28 is provided on the low-pressure loop to control the delivery pressure, and a safety valve 29 is provided on the high-pressure loop to control the high-pressure fuel pressure. A temperature controller 30 is installed between the liquid ammonia storage diverter 31 and the high-pressure pump. An ammonia inlet control valve 33 is connected to the liquid ammonia common rail 1 via the ammonia inlet pipe 17. Liquid ammonia in the liquid ammonia common rail 1 is supplied to the liquid ammonia injector 8 via a double-layer high-pressure oil pipe 2. The inlet of the liquid ammonia storage tank 24 is connected in sequence to the return ammonia control valve 39 and the safety valve 38. The safety valve 38 is connected to the liquid ammonia injector 8 via the return ammonia pipe 18. The liquid ammonia storage tank 24 is connected to the hydrogen storage tank 25 and the nitrogen storage tank 23, respectively. Fuel is supplied to the ammonia inlet 34 via the storage tank 32 and the ammonia inlet control valve 33, and then to the liquid ammonia common rail 1 via the ammonia inlet pipe 17. Excess liquid ammonia in the liquid ammonia injector 8 is supplied to the return ammonia port 35 via the return ammonia pipe 18 and returns to the liquid ammonia storage tank 24 through the safety valve 38 and the return ammonia control valve 39. A liquid ammonia leak detection port 10 is provided at the end of the liquid ammonia common rail 1.

[0043] Figure 3 This is a schematic diagram of the dual-valve coordinated control ammonia fuel injector (liquid ammonia injector 8). It includes a one-way ammonia inlet 40, a boost module 41, an injector body 42, a pressure accumulator resonant current limiting module 44, an ammonia inlet line 45, a pressure-balanced electromagnetic control actuator 46, a nozzle thermal management module 47, and a phase-change controllable super-atomizing nozzle module 48. The injector body 42 is equipped with the one-way ammonia inlet 40 and the ammonia inlet line 45. The boost module 41, the pressure accumulator resonant current limiting module 44, and the pressure-balanced electromagnetic control actuator 46 are located within the injector body 42, arranged sequentially from top to bottom. The phase-change controllable super-atomizing nozzle module 48 is located below the pressure-balanced electromagnetic control actuator 46. The accumulator chamber thermal management module 43 is designed above the pressure accumulator resonant current limiting module 44 and includes a refrigerant inlet 65 and outlet 43, both of which are located on the injector body 42. This allows high-pressure liquid ammonia fuel to be injected into the cylinder, achieving complete combustion. The injection process is also integrated with thermal management, regulating both pressure and temperature to control the phase change of the ammonia fuel. Dual-valve control allows for cyclical and variable liquid ammonia injection, making injection volume and timing more precise and flexible.

[0044] Figure 4This is a detailed schematic diagram of the injector boost module. The boost module 41 includes a yoke 49, a return spring 50, a main and auxiliary magnetic poles 51, a coil 52, an ammonia return channel 53, a boost piston return spring 56, an armature 57, a limit block 58, a valve stem return spring 59, a double-seal valve stem 60, an ammonia inlet channel 61 and an intermediate pipeline 62. An armature 57 is mounted on the top of a double-seal valve stem 60. A return spring 50 is positioned between the yoke 49 and the armature 57. Primary and secondary magnetic poles 51 are located outside the return spring 50, and coils 52 are wound around the primary and secondary magnetic poles 51. The center of the double-seal valve stem 60 is located in the upper valve stem seat, while the bottom of the double-seal valve stem 60 is located in the lower valve stem seat. A valve stem return spring 59 is mounted in the center of the double-seal valve stem 60. A double-seal protrusion is located between the center and bottom of the double-seal valve stem 60. Sealing surfaces are provided on the corresponding surfaces of the upper and lower valve stem seats relative to the double-seal valve stem 60. A booster piston is located below the lower valve stem seat and is sheathed by a booster piston return spring 56. The upper valve stem seat contains a communicating ammonia return channel 53 and an intermediate pipeline, while the lower valve stem seat contains an ammonia supply channel 61 and an intermediate pipeline 62. The space within the lower valve stem seat where the double-seal protrusion resides serves as a connecting space, communicating with the intermediate pipeline. Below the lower surface 63 of the booster piston is a pressure accumulator chamber 64. This module can adopt two control modes, one is the form of liquid ammonia supercharging liquid ammonia, and the other is the form of diesel supercharging liquid ammonia.

[0045] Figure 5 This is a schematic diagram of the pressure accumulator resonance current limiting module, which mainly includes a pressure accumulator chamber 64, a liquid cooling pipe inlet 65, a resonance block 66, a resonance intermediate block 67, a return spring 68, an oil inlet hole 69, a diamond sealing block 70, a flow limiting piston 71, an ammonia inlet channel 72, a storage chamber 73, a resonance block ammonia inlet 74, an intermediate chamber 75, a resonance block ammonia inlet throttle hole 76, a valve seat 77, an intermediate hole 78 and a return spring 79. A pressure accumulator chamber 64 is provided in the injector body 42 below the booster piston, and a liquid cooling pipe inlet 65 is provided on the injector body 42, which is connected to the pressure accumulator chamber 64. A resonance block 66, a resonance intermediate block 67, a diamond sealing block 70 and a valve seat 77 are sequentially provided below the pressure accumulator chamber 64. A flow limiting piston 71 is provided in the valve seat 77, and an intermediate block return spring 68 is provided in the resonance intermediate block 67. An oil inlet hole 69 and a resonance block ammonia inlet throttle hole 76 are respectively provided at the bottom of the resonance intermediate block 67. The diamond sealing block 70 is located above the flow limiting piston 71, and an intermediate hole 78 is provided in the flow limiting piston 71. A flow limiting piston return spring 79 is provided below the flow limiting piston 71, and a storage chamber 73 is provided below the flow limiting piston return spring 79. The flow limiting piston 71 is provided with an intermediate hole 78. Liquid ammonia flows from resonant block 66 into intermediate chamber 75, then flows through oil inlet 69, resonant block ammonia inlet orifice 76, diamond-shaped sealing block 70, and flow-limiting piston 71 into storage chamber 73. The liquid ammonia in storage chamber 73 is then supplied to ammonia tank 104 via ammonia inlet passage 72. This module ensures the stability of ammonia fuel, employing a resonant block to regulate pressure fluctuations within the system. A flow limiter is also designed to prevent abnormal injection.

[0046] Figure 6 Schematic diagram of the resonance block 27, which mainly includes a first ammonia inlet 80, a first ammonia inlet throttle hole 81, a second ammonia inlet throttle hole 82, a first ammonia inlet chamber 83, a first ammonia outlet 84, a second ammonia inlet 85, a second ammonia inlet chamber 86, a connecting hole 87, and a second ammonia outlet 88. The first ammonia inlet chamber 83 is connected to the first ammonia inlet 80 and the first ammonia outlet 84, respectively. The second ammonia inlet chamber 86 is connected to the second ammonia inlet 85 and the second ammonia outlet 88, respectively. The first ammonia inlet chamber 83 and the second ammonia inlet chamber 86 are connected through the connecting hole 87. The first ammonia inlet chamber 83 is connected to the first ammonia inlet 80 through the first ammonia inlet throttle hole 81, and the first ammonia inlet chamber 83 is connected to the pressure accumulator chamber 64 through the second ammonia inlet throttle hole 82.

[0047] Figure 7 This is a schematic diagram of a pressure-balanced electromagnetic control actuator, which mainly includes: main and auxiliary magnetic poles 89, coil 90, piezoelectric armature 91, low-pressure chamber 92, ammonia inlet pipeline 93, return oil throttle hole 94, reset spring 95, balance valve stem 96, oil inlet pipeline 97, oil inlet throttle hole 98 and return oil chamber 99. The piezoelectric main and secondary magnetic poles 89 are located in the injector body 42, and a piezoelectric block and an intermediate block 101 are arranged in sequence below the injector body 42. A low-pressure chamber 92 is arranged at the upper end of the piezoelectric block, and a piezoelectric armature 91 is arranged in the low-pressure chamber 92. The piezoelectric armature 91 is located below the piezoelectric main and secondary magnetic poles 89. A coil 90 is wound on the piezoelectric main and secondary magnetic poles 89. A balancing valve stem 96 passes through the piezoelectric armature 91. The upper end of the balancing valve stem 96 is located in the piezoelectric main and secondary magnetic poles 89, and the lower end of the balancing valve stem 96 is located in the piezoelectric block. An ammonia inlet pipeline 93 is arranged in the piezoelectric block. The balancing valve stem 96 located in the piezoelectric main and secondary magnetic poles 89 is sleeved with a balancing valve stem reset spring 95. A return oil chamber 99 and an oil inlet throttling hole 98 are arranged in the intermediate block. The cavity below the balancing valve stem 96 is connected to the return oil chamber 99 through the return oil throttling hole 94.

[0048] Figure 8This is a schematic diagram of a phase-change controllable super-atomizing nozzle module, which mainly includes a nozzle body, a valve seat, an ammonia inlet pipeline 100, an intermediate block 101, a self-regulating valve block 102, a refrigerant inlet 103, an ammonia tank 104, an injection channel 105, a control chamber 106, a return spring 108, a needle valve body 109, a needle valve sealing surface 110 and a nozzle seat surface 111. The valve seat is located within the nozzle body, and the needle valve body 109 is located within the valve seat. The head of the needle valve body 109 is located within the self-regulating valve block 102, forming a control chamber 106 with it. The self-regulating valve block 102 is located below the intermediate block 101. The control chamber 106 is connected to the oil return chamber 99. A needle valve body return spring 108 is provided between the middle portion of the needle valve body 109 and the self-regulating valve block 102. An ammonia inlet pipeline 100 is formed between the needle valve body 109, the self-regulating valve block 102, and the valve seat. A refrigerant inlet 103 is formed between the valve seat and the nozzle body. The bottom of the needle valve body 109 and the bottom of the valve seat form an injection channel 105. An ammonia reservoir 104 is formed between the injection channel 105 and the ammonia inlet pipeline 100. When the needle valve body 109 is seated, the needle valve sealing surface 110 at its lower end seals with the nozzle seat surface 111 to stop injection.

[0049] Figure 9 This is a schematic diagram of a liquid ammonia-diesel dual-fuel cylinder, primarily comprising a crank 114, piston 16, cylinder 115, air inlet 15, inlet valve stem 113, inlet valve stem spring 112, air outlet 9, outlet valve stem 116, outlet valve stem spring 117, hydrogen inlet 120, safety valve 119, and air inlet 118. Cylinder 115 is provided with air inlet 15, air outlet 9, inlet valve stem 113, and outlet valve stem 116. Air inlet 15 is connected to air inlet 118 and hydrogen inlet 120 via pipelines. A safety valve 119 is provided on the pipeline between hydrogen inlet 120 and air inlet 118. Inlet valve stem 113 is provided with an inlet valve stem spring 112, and outlet valve stem 116 is provided with an outlet valve stem spring 117. A piston 16 is disposed in the cylinder 115 , and the piston 16 is connected to the crank 114 via a crankshaft.

[0050] Figure 10 、 11 The super-atomizing nozzle designed for this project features an inner cone structure for multi-layer sealing. Nearly 100 nozzle holes simultaneously spray, ensuring full atomization of the fuel from a structural perspective. This ensures a complete fusion of fuel and air for complete combustion.

[0051] The liquid ammonia storage tank 24 stores the system's fuel, utilizing high-pressure, low-temperature storage to ensure the ammonia fuel remains in a stable liquid state. During the initial fuel supply phase, hydrogen and nitrogen production modules are installed to convert stored liquid ammonia into ammonia gas. The purified ammonia is then used to produce hydrogen required for combustion and nitrogen required for system purge. These gases are stored in the hydrogen storage tank 25 and nitrogen storage tank 23, respectively. The liquid ammonia stored in the liquid ammonia storage tank 24 first passes through the ammonia pumping system 22, where low-pressure and high-pressure pumps boost the pressure to meet supply and combustion requirements. A relief valve 28 and a safety valve 29 are installed in the low-pressure and high-pressure loops, respectively. The relief valve 28 controls the delivery pressure in the low-pressure loop. If the pressure is too high, excess liquid ammonia is returned to the liquid ammonia storage tank 24 through the relief valve 28. A safety valve 29 controls the high-pressure fuel delivery pressure in the high-pressure loop. Active control adjusts the output pressure, allowing excess liquid ammonia to return to the liquid ammonia storage tank 24 through the safety valve 29. For liquid ammonia, a fuel that is prone to phase change, a thermal management module needs to be set up. The temperature controller 30 is used to adjust the temperature of the liquid ammonia output and control the phase state of the ammonia fuel through both pressure and temperature. The fuel then enters the liquid ammonia storage diverter 31, and the stable supply of fuel is guaranteed through the comprehensive control of the double valve and double chamber. It is then supplied to the ammonia inlet 34 through the storage tank 32 and the ammonia inlet control valve 33, and then introduced into the liquid ammonia common rail pipe 1. The liquid ammonia common rail pipe 1 in the system adopts a double-layer structure to prevent liquid ammonia from leaking into the atmosphere. At the same time, an ammonia leak detection sensor is set at the common rail pipe port to provide timely system feedback. The liquid ammonia in the liquid ammonia common rail pipe 1 is supplied to the liquid ammonia injector 8 through the double-layer high-pressure oil pipe 2, controlled by the solenoid valve in the injector, and then injected into the cylinder.

[0052] Fuel tank 7 stores diesel fuel for the system's pilot combustion. High-pressure fuel pump 4 draws fuel from tank 7. A filter 6 is located between the two, filtering the fuel. The fuel is then delivered to a common rail 11, which has multiple hydraulic oil outlets. Each outlet is connected to an electronically controlled injector 14 via a high-pressure oil pipe 13. The oil is then injected into a cylinder 115, controlled by a solenoid valve within the electronically controlled injector 14.

[0053] Liquid ammonia fuel enters the pressure accumulator 64 through the one-way ammonia inlet 40, which acts as a check valve. When the liquid ammonia supply pressure exceeds the spring preload of the check valve, the poppet valve overcomes the spring force and opens, allowing liquid ammonia to enter the pressure accumulator. When the pressure at the one-way ammonia inlet 40 decreases, the poppet valve closes again, further sealing the liquid ammonia within the system. After entering the pressure accumulator 64, the fuel is fed downward through the resonant block 66. The resonant block 66 consists of three pipes 80, 82, and 85. Fuel flows from these three pipes into the flow restrictor. Ammonia inlet line 80 is the primary flow channel, flowing through ammonia inlet orifice 81, filtering the liquid ammonia flow, before flowing into ammonia inlet chamber 83. Ammonia inlet line 85 is a secondary flow channel, lacking an orifice. After passing through ammonia inlet chamber 86 and ammonia outlet line 88, the fuel flows directly into the flow restrictor. The No. 2 ammonia inlet throttle hole 82 and the connecting hole 87 are the main structures for achieving resonance. By changing the phase of the pressure wave fluctuation, adjusting the fluctuation frequency, and the corresponding relationship between the peaks and troughs, the pressure wave coupling process can be controlled. In particular, in the boost mode, the stability of the system is guaranteed. The flow limiting valve assembly is arranged inside the injector body 42 through the pressure accumulator chamber 40. The resonant intermediate block 67 not only limits the entire flow limiting valve assembly, but also cooperates with the return spring 68. On the one hand, it serves as a spring seat for the return spring 68, and on the other hand, it limits the maximum displacement of the flow limiting piston 71. Under the spring preload of the damping spring and the ball valve return spring, the lower end face of the diamond sealing block 70 cooperates with the flow limiting piston 71 and the upper end face of the support control valve seat 77. Under the spring force of the return spring, the valve seat 77 is pressed against the bottom, and its upper variable cross-section forms the seating surface of the diamond sealing block 70. Liquid ammonia flows from the resonant block 66 into the intermediate chamber 75, then through the oil inlet 69 and the resonant block ammonia inlet orifice 76, respectively, to the flow limiting valve. Under the influence of liquid pressure, the diamond-shaped sealing block 70 moves downward as the liquid ammonia is supplied, overcoming the spring force. When the fuel supply exceeds the limit, the diamond-shaped sealing block 70 cooperates with the valve seat 77 to achieve a seal, disconnecting the fuel supply and preventing cylinder seizure. If the fuel supply is interrupted, the diamond-shaped sealing block 70 quickly returns to its original position due to the spring force.

[0054] After passing through a flow restrictor, liquid ammonia is supplied from the ammonia inlet 72 to the ammonia storage tank 104 and injected into the cylinder by a pressure-balanced electromagnetic control actuator and a super-atomizing nozzle module. In the present invention, diesel is used as the servo oil to ensure precise fuel injector control. By adjusting the pressure level in the control chamber 106, the upward and downward forces on the needle valve body 109 are changed, thereby controlling the injection timing. The present invention adopts a balanced valve control method, with the balanced valve stem 96 being compressed by the piezoelectric armature 91. Because the entire valve is immersed in high-pressure fuel and subjected to the balancing force, a higher common rail pressure (250MPa) can be achieved, thereby reducing the mass of the entire valve component, that is, reducing the electromagnetic force required, and increasing the control response. This requires only a smaller solenoid valve and armature, as well as a smaller spring preload. Furthermore, the balanced valve stem 96 is not directly subjected to high-pressure impact, preventing the cavitation phenomenon of traditional ball valves and increasing system reliability. High-pressure diesel flows from the oil inlet line 97 and the oil inlet orifice 98 into the control chamber 106. When de-energized, the spring preload 95 seals the piezoelectric armature 91 and the balancing valve stem 96, disconnecting the electromagnetic actuator line from the oil return line. Diesel fuel flows from the oil inlet line 97 through the oil inlet orifice 98 to the control chamber 106. The presence of the oil return chamber 99 reduces fuel pressure fluctuations at the control valve. Fuel then flows downward into the control chamber 106, which is sealed by the combination of the intermediate block 101, the self-regulating valve block 102, and the upper end face 107 of the control valve stem. By regulating the pressure in the control chamber 106, the force differential between the upper and lower parts of the needle valve body 109 is altered, achieving precise control of fuel injection. The combined design of the intermediate block 101 and the self-regulating valve block 102 not only solves the leakage problem of conventional systems without a static block, but also prevents wear and leakage caused by needle valve eccentricity through the self-regulating valve block. The specific working principle of the injection process is as follows:

[0055] When operating in non-boost mode, the boost module 41 is de-energized. Due to the balanced pressure across the boost piston's active surfaces, the armature 57 and double-seal valve stem 60 are compressed by the preload of the return spring 50 and the boost piston return spring 56, sealing the ammonia inlet passage 61. During this period, no fuel is supplied to the boost module 41, and the boost piston is in its reset position due to the spring preload, disabling the boost function. Therefore, ammonia fuel in the system passes through the one-way ammonia inlet 40 and is stored in the accumulator chamber 64. It then flows through the resonant block 66 into the flow restrictor valve. The throttling effect of the resonant block 66 on the liquid ammonia increases the fuel pressure in the accumulator chamber 64, creating a pressure differential with the pressure in the transition oil chamber. Consequently, the flow restrictor piston 71 and diamond-shaped seal 70 move downward as a whole, compensating for the injection pressure. Liquid ammonia passing through the flow restrictor valve is supplied to the ammonia storage tank 104 via the ammonia inlet passage 72. When the pressure-balanced electromagnetic actuator is energized, the magnetic field causes the piezoelectric armature 91 to move upward, overcoming the preload of the return spring 95. This opens the oil return passage, connecting the control chamber 106 to the low-pressure leak hole. Fuel in the control chamber 106 flows back into the low-pressure chamber 92 through the low-pressure leak hole. When the combined force of the pressure in the control chamber 106 and the force of the return spring 108 becomes less than the upward hydraulic pressure in the ammonia tank 104, the needle valve body 109 lifts upward, opening the spray hole and allowing the injector to begin spraying ammonia. When the ammonia injection control valve is partially de-energized, the magnetic field is removed and the spring preload causes the piezoelectric armature 91 to move downward, resealing the oil return passage. This simultaneously drives the balancing valve stem 96 downward, sealing the oil return passage. Pressure in the control chamber 106 builds up again through the oil inlet orifice 98. When the combined force of the pressure in the control chamber 106 and the force of the return spring 108 becomes greater than the upward hydraulic pressure in the ammonia tank 104, the needle valve body 109 reseats, and the injector ceases spraying. When the injector stops working, as the liquid ammonia flows through the middle hole 78, the pressure difference between the upper and lower surfaces of the flow limiting piston 71 will gradually decrease. Under the action of the return spring, the flow limiting piston 71 and the diamond-shaped sealing block 70 return to their initial positions as a whole.

[0056] When operating in boost mode, the boost module 41 and coil 52 are energized, generating electromagnetic forces on the primary and secondary magnetic poles 51 that attract the armature 57 upward. This simultaneously drives the double-seal valve stem 60 upward, opening the ammonia inlet channel 61 and closing the ammonia return channel 53. Liquid ammonia accumulates on the upper surface 54 of the boost piston, increasing the force on the upper surface. The pressure differential between the upper and lower surfaces overcomes the spring force, causing the boost piston to move downward. This compresses the volume of the lower pressure accumulator chamber 64, increasing the pressure. Both the boost module 41 and the pressure-balanced electromagnetic actuator can adopt two control modes: one for boosting liquid ammonia with liquid ammonia, and the other for boosting liquid ammonia with diesel. In the boost module 41, the intermediate chamber 55 serves as a leakage collector for boosted oil, while the fuel acts as a seal against the liquid ammonia. The pressurized liquid ammonia flows through the resonant block 66 into the flow control valve. After passing through the flow control valve, the liquid ammonia is supplied to the ammonia storage tank 104 via the ammonia inlet channel 72. When the pressure-balanced electromagnetic actuator is energized, the magnetic field causes the piezoelectric armature 91 to move upward, overcoming the preload of the return spring 95. This opens the oil return passage, connecting the control chamber 106 to the low-pressure leak hole. Fuel in the control chamber 106 flows back into the low-pressure chamber 92 through the low-pressure leak hole. When the combined force of the pressure in the control chamber 106 and the force of the return spring 108 becomes less than the upward hydraulic pressure in the ammonia tank 104, the needle valve body 109 lifts upward, opening the spray hole and allowing the injector to begin spraying ammonia. When the ammonia injection control valve is partially de-energized, the magnetic field is removed and the spring preload causes the piezoelectric armature 91 to move downward, resealing the oil return passage. This simultaneously drives the balancing valve stem 96 downward, sealing the oil return passage. Pressure in the control chamber 106 builds up again through the oil inlet orifice 98. When the combined force of the pressure in the control chamber 106 and the force of the return spring 108 becomes greater than the upward hydraulic pressure in the ammonia tank 104, the needle valve body 109 reseats, and the injector ceases spraying.

[0057] A thermal management module is designed within the pressure-accumulating resonant current-limiting module 44 and the super-atomizing nozzle module 48, including refrigerant inlets 65 and 103 and outlet 43. The liquid ammonia phase is controlled through comprehensive temperature and pressure control, achieving controllable liquid ammonia phase during the injection process.

[0058] The liquid ammonia-diesel dual-fuel cylinder is responsible for fuel-air mixing and fuel combustion, converting chemical energy into kinetic energy. The system utilizes a liquid ammonia dual-fuel combustion mode with diesel as the ignition source and hydrogen as the auxiliary combustion source. Diesel and liquid ammonia are injected into cylinder 115 by electronically controlled injectors 14 and 8, respectively. Hydrogen, controlled by safety valve 119, mixes with air injected through intake port 118 through intake port 120 and is then supplied to the cylinder through intake port 15. When the mixture is ready to be introduced, the intake valve stem opens, allowing the mixture to enter the cylinder and mix with the fuel. The crankshaft then drives crank 114 upward. When it reaches top dead center, combustion occurs via compression ignition, driving the valve stem to generate power. Because ammonia fuel has a higher resistance to detonation, a higher compression ratio (20:1) is employed in the cylinder and piston design to increase thermal efficiency. When combustion is complete, the exhaust valve stem 116 opens, discharging the exhaust gases. During the movement of the valve stem, the inlet valve stem spring 112 and the outlet valve stem spring 117 play a role of resetting.

[0059] During system operation, excess diesel fuel returns to fuel tank 7 via oil return line 5. Excess liquid ammonia returns to liquid ammonia storage tank 24 via ammonia return line 18 and safety valve 38. Nitrogen acts as a purge in the liquid ammonia fuel supply system and is used in multiple pipelines.

[0060] As can be seen from the above description, the present invention utilizes a low-pressure storage tank as a medium to achieve safe storage of liquid ammonia. A parallel liquid ammonia hydrogen production reaction mechanism provides a hydrogen supply source for fuel cells and engines, as well as ammonia fuel for the engines, significantly improving storage efficiency. The proposed diesel-ignited, hydrogen-assisted combustion mode alleviates the problems of difficult combustion and insufficient reaction of ammonia fuel. Furthermore, the liquid ammonia and hydrogen supply systems utilize a double-layer high-pressure oil pipe and a double-layer common rail structure, with detection sensors and nitrogen purge devices installed at the interlayer interface to ensure that the system can promptly detect ammonia fuel leaks, achieving intrinsic safety. Furthermore, the injection process incorporates thermal management design, regulating both pressure and temperature to control the phase change of ammonia fuel. Dual-valve control allows for cyclical and variable liquid ammonia injection, making injection quantity and timing more precise and flexible. The use of a balanced valve control method, due to the entire system being immersed in high-pressure fuel and subject to the balancing force, can achieve a higher common rail pressure (250 MPa), thereby reducing the overall valve mass, thereby reducing the electromagnetic force required and increasing control efficiency. This requires a smaller solenoid valve and armature, as well as less spring preload. Furthermore, the balanced valve stem is protected from direct impact, preventing the cavitation associated with traditional ball valves and increasing system reliability. The combination of an intermediate block and a self-regulating valve block not only solves the leakage issues associated with traditional valves without a static block, but also prevents wear and leakage caused by needle valve eccentricity through the self-regulating valve block.

[0061] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A dual-valve coordinated control hydrogen-assisted combustion liquid ammonia-diesel dual fuel injection system, characterized by: It includes an electronically controlled fuel injector, a liquid ammonia injector, a liquid ammonia common rail pipe, a fuel common rail pipe, a fuel tank, a liquid ammonia storage tank, an ammonia pump system, a diversion system and an ammonia inlet and outlet system. The fuel common rail pipe is respectively connected to the electronically controlled fuel injector and the fuel tank, and the liquid ammonia common rail pipe is respectively connected to the liquid ammonia injector and the ammonia inlet and outlet system. An ammonia inlet pipe and an ammonia return pipe are arranged in the ammonia inlet and outlet system. The ammonia pump system includes a liquid ammonia storage diverter, a low-pressure pump and a high-pressure pump. The diversion system includes a storage tank, an ammonia inlet control valve, a safety valve and a return ammonia control valve. The outlet of the liquid ammonia storage tank is sequentially connected to the low-pressure pump, the high-pressure pump, the liquid ammonia storage diverter, the storage tank and the ammonia inlet control valve. The ammonia inlet control valve is connected to the ammonia inlet pipe. The liquid ammonia common rail pipe and the inlet of the liquid ammonia storage tank are connected to the ammonia return control valve and the safety valve in sequence. The safety valve is connected to the liquid ammonia injector through the ammonia return pipe. The liquid ammonia storage tank is connected to the hydrogen storage tank and the nitrogen storage tank respectively. The electronically controlled fuel injector includes an injector body, a boost module, a pressure accumulator resonance current limiting module, a pressure-balanced electromagnetic control actuator and a phase-change controllable super-atomizing nozzle module. The injector body is provided with a one-way ammonia inlet and an ammonia inlet pipeline. The boost module, the pressure accumulator resonance current limiting module and the pressure-balanced electromagnetic control actuator are located in the injector body and are arranged in sequence from top to bottom. The phase-change controllable super-atomizing nozzle module is located below the pressure-balanced electromagnetic control actuator. The boost module includes a magnetic yoke, a main and auxiliary magnetic poles, a boost piston, an armature, a limit block, a double-sealed valve stem, an upper valve stem seat and a lower valve stem seat. The armature is sleeved on the top of the double-sealed valve stem. A reset spring is arranged between the magnetic yoke and the armature. The main and auxiliary magnetic poles are arranged on the outside of the reset spring. The main and auxiliary magnetic poles are wound with coils. The middle part of the double-sealed valve stem is located in the upper valve stem seat, and the bottom of the double-sealed valve stem is located in the lower valve stem seat. The middle part of the double-sealed valve stem is sleeved with a valve stem reset spring. A double sealing protrusion is provided between the middle and bottom of the double sealing valve stem, and sealing surfaces are provided on the surfaces corresponding to the upper valve stem seat and the lower valve stem seat and the double sealing valve stem. The boosting piston is located below the lower valve stem seat, and a boosting piston return spring is sleeved on the outside of the boosting piston. A communicating ammonia return channel and an intermediate pipeline are provided in the upper valve stem seat, and an ammonia inlet channel is provided in the lower valve stem seat. The space in the lower valve stem seat where the double sealing protrusion is located is a communicating space, and the communicating space is communicated with the intermediate pipeline. The pressure accumulator resonance current limiting module includes a resonance block, a resonance middle block, a diamond sealing block, a current limiting piston and a valve seat. A pressure accumulator chamber is provided in the injector body below the boosting piston. A liquid cooling pipe inlet is provided on the injector body, and the liquid cooling pipe inlet is connected to the pressure accumulator chamber. The resonance block, the resonance middle block, the diamond sealing block and the valve seat are sequentially provided below the pressure accumulator chamber. The current limiting piston is provided in the valve seat, and the middle block return spring is provided in the resonance middle block. The bottom of the resonance middle block is respectively provided with an oil inlet hole and a resonance block ammonia inlet throttle hole. The diamond sealing block is located above the current limiting piston, and a middle hole is provided in the current limiting piston. A current limiting piston return spring is provided below the current limiting piston, and a storage chamber is provided below the current limiting piston return spring. The resonance block is respectively provided with a No. 1 ammonia inlet, a No. 2 ammonia inlet, a No. 1 ammonia inlet cavity, a No. 2 ammonia inlet cavity, a No. 1 ammonia outlet and a No. 2 ammonia outlet. The No. 1 ammonia inlet cavity is respectively connected to the No. 1 ammonia inlet and the No. 1 ammonia outlet, and the No. 2 ammonia inlet cavity is respectively connected to the No. 2 ammonia inlet and the No. 2 ammonia outlet. The No. 1 ammonia inlet cavity is connected to the No. 2 ammonia inlet cavity through a connecting hole. The No. 1 ammonia inlet cavity is connected to the No. 1 ammonia inlet through the No. 1 ammonia inlet throttle hole, and the No. 1 ammonia inlet cavity is connected to the pressure accumulator through the No. 2 ammonia inlet throttle hole. The pressure-balanced electromagnetic control actuator includes piezoelectric main and auxiliary magnetic poles, a piezoelectric armature and a balancing valve stem, the piezoelectric main and auxiliary magnetic poles are located in the injector body, a piezoelectric block and an intermediate block are sequentially arranged below the injector body, a low-pressure chamber is arranged at the upper end of the piezoelectric block, the piezoelectric armature is arranged in the low-pressure chamber, the piezoelectric armature is located below the piezoelectric main and auxiliary magnetic poles, the balancing valve stem passes through the piezoelectric armature, the upper end of the balancing valve stem is located in the piezoelectric main and auxiliary magnetic poles, the lower end of the balancing valve stem is located in the piezoelectric block, the balancing valve stem located in the piezoelectric main and auxiliary magnetic poles is sleeved with a balancing valve stem reset spring, an oil return chamber and an oil inlet throttle hole are arranged in the intermediate block, and the chamber below the balancing valve stem is connected to the oil return chamber through the oil return throttle hole; The phase change controllable super atomizing nozzle module includes a nozzle body, a nozzle module valve seat, a needle valve body and a self-regulating valve block. The nozzle module valve seat is located in the nozzle body, the needle valve body is located in the nozzle module valve seat, the head of the needle valve body is located in the self-regulating valve block and forms a control chamber with it, the self-regulating valve block is located below the intermediate block, the control chamber is connected to the return oil chamber, a needle valve body reset spring is arranged between the middle part of the needle valve body and the self-regulating valve block, an ammonia inlet pipeline is formed between the needle valve body, the self-regulating valve block and the nozzle module valve seat, a refrigerant inlet is formed between the nozzle module valve seat and the nozzle body, an injection channel is formed between the bottom of the needle valve body and the bottom of the nozzle module valve seat, and an ammonia tank is formed between the injection channel and the ammonia inlet pipeline.

2. A control method for a dual-valve coordinated control hydrogen-assisted combustion liquid ammonia-diesel dual fuel injection system according to claim 1, characterized in that: Including no-boost control mode and boost control mode; No-boost control mode: The boost module is de-energized, the ammonia inlet channel is sealed, and the boost piston is in a reset state under the action of the spring preload. Ammonia fuel passes through the one-way ammonia inlet and is stored in the pressure accumulator chamber. The flow-limiting piston and the diamond-shaped sealing block move downward as a whole. When the pressure-balanced electromagnetic control actuator is energized, the piezoelectric armature overcomes the piezoelectric spring preload and moves upward. The fuel in the control chamber flows back to the low-pressure chamber through the oil return throttle hole. When the combined force of the pressure in the control chamber and the elastic force of the needle valve body return spring is less than the upward hydraulic pressure in the ammonia tank, the needle valve body lifts upward. When the pressure-balanced electromagnetic control actuator is partially de-energized, the piezoelectric armature moves downward, driving the balancing valve stem downward to achieve sealing. The control chamber is re-pressurized through the oil inlet throttle hole. When the combined force of the pressure in the control chamber and the elastic force of the needle valve body return spring is greater than the upward hydraulic pressure in the ammonia tank, the needle valve body re-seates, the injection system stops spraying, and the flow-limiting piston and the diamond-shaped sealing block return to their initial positions as a whole. Booster control mode: When the boost module is powered on, the armature moves upward, driving the double-seal valve stem to move upward, opening the ammonia inlet channel and closing the ammonia return channel. Liquid ammonia accumulates on the upper surface of the boost piston, causing the boost piston to move downward. When the pressure-balanced electromagnetic control actuator is energized, the piezoelectric armature overcomes the preload of the piezoelectric return spring and moves upward, and the fuel in the control chamber flows back to the low-pressure chamber through the return oil throttle hole. When the combined force of the pressure in the control chamber and the elastic force of the needle valve body return spring is less than the upward liquid pressure in the ammonia tank, the needle valve body lifts up. When the pressure-balanced electromagnetic control actuator is partially powered off, the piezoelectric armature moves downward, resealing the return oil circuit and driving the balancing valve stem downward to achieve sealing. The control chamber is re-pressurized through the oil inlet throttle hole. When the combined force of the pressure in the control chamber and the elastic force of the needle valve body return spring is greater than the upward liquid pressure in the ammonia tank, the needle valve body re-seates and the injection system stops injecting.

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