Variable combustion jet ignition free piston power generation system and control method

Abstract

The invention provides a variable combustion jet ignition free piston power generation system and a control method, and relates to the technical field of internal combustion generators, the variable combustion jet ignition free piston power generation system comprises a linear motor, a connecting rod assembly, a jet ignition free piston engine, a state acquisition system and a control system; the linear motor is connected with the jet ignition free piston engine through a connecting rod assembly; the jet ignition free piston engine comprises a cylinder body, a piston and a pre-combustion chamber. A first oil injector and a second oil injector are respectively mounted on an air inlet pipeline and a main combustion chamber of the cylinder body; a third oil sprayer is mounted in the pre-combustion chamber; the running state of the jet flow ignition free piston power generation system is collected through the state collection system and transmitted to the control system, and the control system sends out a control signal to control the first oil sprayer, the second oil sprayer and the third oil sprayer. According to the invention, the combustion process in the cylinder body of the system is improved, and the adaptability of the system to low-activity fuel is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of internal combustion generators, and in particular to a variable combustion jet ignition free piston power generation system and a control method. Background Art

[0002] The free-piston internal combustion generator includes a free-piston engine and a linear motor. The piston of the free-piston engine is directly coupled to the linear motor rotor through a connecting rod, and electrical energy is directly output through the linear reciprocating motion of the piston. It has the advantages of simple structure, short energy transfer chain, high energy conversion efficiency and flexible and adjustable compression ratio. Due to its direct output of electrical energy, it can be used in new energy vehicle range extenders, isolated island power generation, ship power generation, etc., and has broad application prospects.

[0003] The variable combustion jet-ignited free piston power generation system optimizes combustion efficiency, power output and power generation efficiency by precisely controlling the combustion process and piston movement. It can dynamically adjust the combustion method and injection strategy according to different system modes, and use jet ignition technology to improve flame propagation and isochoric combustion effects in the early stage of combustion, which helps to further improve the system adaptability and overall performance.

[0004] However, traditional free piston power generation systems usually adopt a two-stroke working mode during operation, which results in a long combustion duration, making it difficult to achieve fast and efficient combustion, and the overall combustion efficiency of the system is low. Traditional free piston power generation systems have poor adaptability to low-activity fuels, making it difficult to fully burn in the system, reducing the energy conversion efficiency of the system. Summary of the invention

[0005] In order to solve the technical problems that traditional free piston power generation systems usually adopt a two-stroke working mode during operation, resulting in a long combustion duration, difficulty in achieving fast and efficient combustion, low overall combustion efficiency of the system, and poor adaptability of traditional free piston power generation systems to low-activity fuels, which makes it difficult to fully burn in the system, thereby reducing the energy conversion efficiency of the system, the present invention provides a variable combustion jet-ignited free piston power generation system and a control method.

[0006] The technical solution provided by the embodiment of the present invention is as follows:

[0007] First aspect:

[0008] A variable combustion jet-ignited free piston power generation system provided by an embodiment of the present invention comprises: a linear motor, a connecting rod assembly, a jet-ignited free piston engine, a state acquisition system and a control system;

[0009] The linear motor is connected to the jet-ignition free piston engine through a connecting rod assembly;

[0010] The jet-ignited free piston engine comprises a cylinder, a piston and a pre-combustion chamber;

[0011] The first fuel injector and the second fuel injector are respectively installed in the air intake pipeline and the main combustion chamber of the cylinder body;

[0012] A third fuel injector is installed in the pre-combustion chamber;

[0013] The operating status of the jet-ignited free piston power generation system is collected through the status acquisition system, and the operating status is transmitted to the control system. The control system sends a control signal to control the first injector, the second injector and the third injector.

[0014] Second aspect:

[0015] A control method provided in an embodiment of the present invention is applied to the variable combustion jet ignition free piston power generation system provided in the first aspect, and the method includes:

[0016] S1: Collect the operating status of the jet ignition free piston power generation system through the status acquisition system;

[0017] S2: optimizing the power generation capacity of the jet-ignited free piston power generation system in different system modes using the control system according to the operating state;

[0018] Among them, the system modes include normal mode, sports mode and energy-saving mode.

[0019] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0020] In the present invention, according to the operating state of the jet-ignited free piston power generation system, a control signal is sent through the control system to control the injector, flexibly switching the pre-combustion chamber jet mode and the main combustion chamber combustion mode, thereby improving the combustion efficiency and the system's in-cylinder combustion process, so that the system can better adapt to different working modes, effectively broaden the fuel applicability of the free piston internal combustion generator, and promote the application and development of the free piston internal combustion generator technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of 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 creative work.

[0022] Figure 1 A schematic diagram of the structure of a variable combustion jet-ignited free piston power generation system provided by an embodiment of the present invention;

[0023] Figure 2 A schematic diagram of a premixed combustion structure of a variable combustion jet-ignited free piston power generation system provided by an embodiment of the present invention;

[0024] Figure 3 A schematic diagram of a diffusion combustion structure of a variable combustion jet-ignited free piston power generation system provided by an embodiment of the present invention;

[0025] Figure 4 A flow chart of a control method provided by an embodiment of the present invention.

[0026] [reference numerals]

[0027] 1. Mover; 2. Stator; 3. Motor housing; 4. Linear motor displacement sensor; 5. Motor end spring seat; 6. Spring; 7. Connecting rod; 8. Piston end spring seat; 9. Premix injector; 10. Intake pipe; 11. Cylinder block; 12. Piston; 13. Piston pin; 14. Piston ring; 15. Diffusion injector; 16. In-cylinder pressure sensor; 17. Precombustion chamber injector; 18. Precombustion chamber; 19. Spark plug; 20. Cylinder wall temperature sensor; 21. Oxygen sensor; 22. Exhaust pipe.

[0028] As shown in the figure, in order to clearly implement the structure of the embodiment of the present invention, specific structures and devices are marked in the figure, but this is only for illustrative purposes and is not intended to limit the present invention to the specific structure, device and environment. According to specific needs, ordinary technicians in this field can adjust or modify these devices and environments. DETAILED DESCRIPTION

[0029] The technical solution of the present invention is described below in conjunction with the accompanying drawings. It is also noted that, in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternatives to implement some known technologies; and the accompanying drawings are only for more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0030] It should be noted that the embodiments indicated by "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments" etc. in the specification may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of technicians in the relevant field to implement such feature, structure or characteristic in conjunction with other embodiments (whether explicitly described or not).

[0031] In general, a term can be understood, at least in part, from its use in context. For example, depending, at least in part, on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending, at least in part, on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0032] It will be understood that the meanings of “on,” “over,” and “above” in the present invention should be interpreted in the broadest manner, so that “on” not only means “directly on” something, but also includes the meaning of being “on” something with intervening features or layers therebetween, and “on” or “over” not only means “on” or “above” something, but also includes the meaning of being “on” or “above” something with no intervening features or layers therebetween.

[0033] Additionally, spatially relative terms such as "under," "beneath," "lower," "above," "upper," and the like may be used herein for descriptive convenience to describe the relationship of one element or feature to another element or features, as shown in the accompanying drawings. Spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the accompanying drawings. The device may be oriented in other ways, and the spatially relative descriptors used herein may be similarly interpreted accordingly.

[0034] Reference Manual Attached Figure 1 , showing a schematic diagram of the mechanism of a variable combustion jet-ignited free piston power generation system provided by an embodiment of the present invention.

[0035] Reference Manual Attached Figure 2 , showing a schematic diagram of the premixed combustion structure of a variable combustion jet-ignited free piston power generation system provided by an embodiment of the present invention.

[0036] like Figure 2 The fuel is sprayed into the cylinder through the injector located in the intake pipe and is fully mixed with the incoming air to form an oil-gas mixture. In the premixed combustion mode, the fuel achieves a high degree of atomization and mixing before entering the combustion chamber, which is beneficial to the uniformity and stability of the combustion process. The spark plug is located in the precombustion chamber and is responsible for igniting the premixed gas. The flame then propagates to the main combustion chamber to achieve an efficient combustion process. This structure can optimize combustion efficiency and reduce energy loss and emissions caused by incomplete combustion.

[0037] Reference Manual Attached Figure 3, showing a schematic diagram of the diffusion combustion structure of a variable combustion jet-ignited free piston power generation system provided by an embodiment of the present invention.

[0038] like Figure 3 In the diffusion combustion mode, the fuel is sprayed directly into the main combustion chamber through the injector. The fuel and air are gradually mixed during the combustion process and ignited by the flame in the pre-combustion chamber. The flame propagates from the pre-combustion chamber to the main combustion chamber, combines with the newly injected fuel and begins diffusion combustion. This combustion method is suitable for the case where the fuel and air are not completely mixed. Combustion is achieved through flame propagation and molecular diffusion. It has the advantages of stable flame propagation, fast combustion speed, and adaptability to a variety of fuels, which helps to improve the system's power and combustion efficiency.

[0039] An embodiment of the present invention provides a variable combustion jet-ignited free piston power generation system, comprising: a linear motor, a connecting rod assembly, a jet-ignited free piston engine, a state acquisition system and a control system.

[0040] The linear motor is connected to the jet-ignition free piston engine through a connecting rod assembly.

[0041] The jet-ignition free piston engine comprises a cylinder 11 , a piston 12 and a pre-combustion chamber 13 .

[0042] The intake pipe of the cylinder block 11 and the main combustion chamber are respectively installed with a first fuel injector 9 and a second fuel injector 15 .

[0043] The third fuel injector 17 is installed in the pre-combustion chamber 18 .

[0044] The operating status of the jet-ignited free piston power generation system is collected by the status acquisition system, and the operating status is transmitted to the control system. The control system sends a control signal to control the first injector 9, the second injector 15 and the third injector 17.

[0045] It should be noted that the state acquisition system monitors the system operating status such as pressure, temperature and oxygen concentration in real time, and the control system accurately adjusts the working status of each injector to achieve flexible switching of different combustion modes. This control method can dynamically optimize the combustion process according to operating conditions, improve combustion efficiency, system power and economy, and effectively adapt to a variety of fuels, enhancing the system's operating stability and adaptability.

[0046] In a possible implementation, the linear motor includes a mover 1 , a stator 2 and a motor housing 3 .

[0047] The linear motor is internally provided with a permanent magnet to generate a magnetic field, which drives the mover 1 to perform linear motion.

[0048] It should be noted that the linear motor generates a magnetic field through the stator and directly drives the mover to perform linear motion, eliminating the rotation-linear conversion mechanism of the traditional motor. This design has a simple structure, fast response, and low energy loss. It can improve the transmission efficiency and accuracy of the system, while reducing mechanical wear and maintenance costs, and improving the overall reliability of the system.

[0049] In a possible implementation, the first fuel injector 9 and the second fuel injector 15 are used to adapt to different combustion modes of the jet-ignited free-piston internal combustion generator.

[0050] The third fuel injector 17 is used to switch the injection mode.

[0051] A spark plug 19 is installed inside the pre-combustion chamber 13, and the spark plug 19 is used to ignite the mixture in the pre-combustion chamber.

[0052] It should be noted that the first injector and the second injector adapt to different combustion modes, and the third injector switches the jet mode to cooperate with the spark plug in the pre-combustion chamber to ignite the mixture, which can flexibly control the combustion process according to working conditions and optimize combustion efficiency and stability.

[0053] In a possible implementation manner, the connecting rod assembly includes a motor-end spring seat 5 , a spring 6 , a connecting rod 7 and a piston-end spring seat 8 .

[0054] The spring 6 is arranged between the motor end spring seat 5 and the piston end spring seat 8 and is sleeved on the connecting rod 7.

[0055] The two ends of the connecting rod 7 are respectively connected to the mover main shaft 1 and the piston 12 by bolts.

[0056] It should be noted that the connecting rod assembly realizes an efficient connection between the linear motor and the piston through the motor-end spring seat, spring and piston-end spring seat. The setting of the spring effectively buffers the impact force during the movement of the mover and piston, reduces mechanical wear and extends the service life of the system. The connecting rod is fixed by bolts, with a simple structure and easy installation and maintenance, ensuring the reliability and stability of the system.

[0057] In a possible implementation, the state acquisition system includes a linear motor displacement sensor 4 , an in-cylinder pressure sensor 16 , a cylinder wall temperature sensor 20 , and an oxygen sensor 21 .

[0058] The linear motor displacement sensor 4 is mounted on the motor housing 3 and is used to record the position information of the jet ignition free piston power generation system during operation.

[0059] The in-cylinder pressure sensor 16 is installed in the top area of ​​the cylinder head of the main combustion chamber of the cylinder body 11, and is used to record the change of gas pressure in the main combustion chamber during the operation of the jet ignition free piston power generation system.

[0060] The cylinder wall temperature sensor 20 is installed in the middle area of ​​the cylinder head and is used to record the change of the cylinder wall temperature during the operation of the jet ignition free piston power generation system.

[0061] The oxygen sensor 21 is installed in the exhaust pipe to record the oxygen concentration of the exhaust gas generated by the jet ignition free piston power generation system during operation.

[0062] It should be noted that the status acquisition system collects key system operation data in real time through linear motor displacement sensors, in-cylinder pressure sensors, cylinder wall temperature sensors and oxygen sensors. These data provide an accurate basis for monitoring and adjusting the system's combustion process, which can optimize combustion efficiency, achieve multi-mode flexible control, and detect abnormal situations in a timely manner, ensuring efficient and stable operation of the system under different working conditions and improving the overall performance and reliability of the system.

[0063] In a possible implementation, the control system includes a host computer and a control ECU.

[0064] The control ECU is connected to the first fuel injector 9, the second fuel injector 15, the third fuel injector 17, the spark plug 19, the state acquisition system and the motor controller respectively through connecting lines.

[0065] The state acquisition system transmits the collected data to the host computer, which analyzes the combustion process in the cylinder based on the collected data and transmits the control signal to the control ECU.

[0066] It should be noted that the control system realizes closed-loop control of data collection, analysis and command execution through the collaboration between the host computer and the control ECU. The status acquisition system provides real-time operation data. The host computer accurately analyzes the combustion process in the cylinder based on this data and sends control signals to the ECU, thereby flexibly adjusting the working status of the injector, spark plug and motor controller, ensuring precise control of the system under different working conditions, improving combustion efficiency, power output and economy, while enhancing the adaptability and stability of the system to meet the needs of various fuels and modes.

[0067] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0068] In the present invention, according to the operating state of the jet-ignited free piston power generation system, a control signal is sent through the control system to control the injector, flexibly switching the pre-combustion chamber jet mode and the main combustion chamber combustion mode, thereby improving the combustion efficiency and the system's in-cylinder combustion process, so that the system can better adapt to different working modes, effectively expand the fuel applicability of the free piston internal combustion generator, and promote the application and development of the free piston internal combustion generator technology.

[0069] Reference Manual Attached Figure 4, showing a flow chart of a control method provided by the present invention.

[0070] The present invention also provides a control method, which is applied to a variable combustion jet ignition free piston power generation system, and the method comprises:

[0071] S1: Collect the operating status of the jet-ignited free piston power generation system through the status acquisition system.

[0072] It should be noted that the status acquisition system can monitor the key operating parameters of the jet-ignited free piston power generation system in real time, such as position information, cylinder pressure, cylinder wall temperature and exhaust oxygen concentration, and provide accurate data support for the system's combustion state, output power and operating efficiency, ensuring that the control system can respond quickly and make precise adjustments, thereby optimizing the combustion process, improving system performance and stability, and meeting the needs of efficient operation under multiple working conditions.

[0073] S2: According to the operating state, the control system is utilized to optimize the power generation capacity of the jet-ignited free piston power generation system in different system modes.

[0074] Among them, the system modes include normal mode, sports mode and energy-saving mode.

[0075] It should be noted that the control system flexibly switches between different system modes based on the operating status data collected in real time to meet the needs under different working conditions. In normal mode, the system balances power and economy; in sports mode, it improves power output; in energy-saving mode, it optimizes combustion efficiency, reduces fuel consumption and emissions. This intelligent control effectively improves the adaptability, operating efficiency and stability of the system, ensuring that the power generation system achieves optimal performance under a variety of working conditions.

[0076] In actual operation, the host computer sends a start command to the control ECU, and the system starts cold under the drag of the linear motor. When the cylinder pressure collected by the cylinder pressure sensor is greater than 8 bar, the pressure required for ignition is met. At this time, a judgment is made based on the type of fuel used. When the fuel has high requirements on atomization characteristics, diesel, hydrogen, aviation kerosene, etc. choose to install the injector in the cylinder body. When the fuel has general requirements on atomization characteristics, gasoline, natural gas, alcohol, etc. choose to install the injector in the intake pipe. Then the host computer sends a command to the spark plug to ignite, and the combustion system starts working. When the system runs continuously and stably for 1 minute, the linear motor switches from electric mode to power generation mode.

[0077] In a possible implementation, when the system mode is the normal mode, optimizing the power generation capacity of the jet-ignited free piston power generation system specifically includes:

[0078] The gas pressure in the cylinder and the system position information of the jet ignition free piston power generation system are detected respectively by the in-cylinder pressure sensor and the linear motor displacement sensor.

[0079] The system output work of the jet-ignited free piston power generation system is determined by gas pressure and system position information.

[0080] When the system output power is lower than the preset system output power, the control system is used to control the activation of the third injector, switch the jet mode to the active jet mode, optimize the power generation capacity of the jet-ignited free piston power generation system, and improve the work capacity of the jet-ignited free piston power generation system.

[0081] When the system output power is higher than the preset system output power, the control system is used to control the jet-ignited free piston power generation system to stop working, so as to avoid the waste of the output power of the jet-ignited free piston power generation system.

[0082] Among them, according to the gas pressure p in the cylinder, the displacement information x, the cylinder diameter D and the running stroke S of the free piston generator, the corresponding system work can be deduced:

[0083] V=0.25πD 2 (Sx)

[0084] W=∫pVdt

[0085] Among them, V represents the volume of the cylinder, D represents the diameter of the rigid body, S represents the operating stroke of the free piston generator, x represents the displacement information, W represents the work of the free piston power generation system, and p represents the gas pressure in the cylinder.

[0086] It should be noted that by real-time monitoring of the cylinder pressure and system position information, the output power can be accurately determined, and the control system dynamically adjusts the power generation status to ensure that the system output power meets the demand, while avoiding energy waste, achieving a balance between power and economy, and improving the overall efficiency and stability of the system.

[0087] Specifically, when the system switches to normal mode, the system needs to take into account both power and economy. The in-cylinder gas pressure is detected by the in-cylinder pressure sensor and the system position information is detected by the linear motor displacement sensor to determine the system output power at this time, and the system output power is compared with the design value. When the output power is lower than the design value, the upper computer sends a command to the control ECU to start the pre-combustion chamber injector to increase the fuel concentration in the pre-combustion chamber, improve the initial state of flame propagation, and increase the combustion isochoricity, thereby improving the system's work capacity; when the output power is higher than the design value, the upper computer sends a command to the control ECU to stop the pre-combustion chamber injector to avoid waste of system output power, thereby taking into account both system power and economy.

[0088] It should be noted that those skilled in the art can set the size of the preset system output power according to actual conditions, and the present invention does not limit this.

[0089] In a possible implementation, when the system mode is the motion mode, optimizing the power generation capacity of the jet-ignited free piston power generation system specifically includes:

[0090] The cylinder wall temperature is detected by the cylinder wall temperature sensor.

[0091] The combustion state in the cylinder is determined based on the cylinder wall temperature.

[0092] When the cylinder wall temperature is lower than the preset wall temperature, the control system is used to activate the second injector, switch the combustion mode to the diffusion combustion mode, optimize the power generation capacity of the jet-ignited free piston power generation system, and improve the system dynamics of the jet-ignited free piston power generation system.

[0093] It should be noted that those skilled in the art can set the preset wall temperature according to actual conditions, and the present invention does not limit this.

[0094] It should be noted that the cylinder wall temperature sensor is used to monitor the cylinder wall temperature in real time and accurately judge the combustion status in the cylinder. When the temperature is lower than the preset value, the system automatically adjusts the combustion process to improve the combustion completeness and power output, ensuring that the system operates efficiently and stably under high power demand.

[0095] Specifically, when the system switches to sports mode, the system needs good power. The cylinder wall temperature is detected by the cylinder wall temperature sensor to determine the combustion state in the cylinder. When the cylinder wall temperature is lower than 100°C, the combustion process in the cylinder is not sufficient. The host computer sends a command to the control ECU. In the diffusion combustion mode, the injection pulse width of the pre-combustion chamber injector and the main combustion chamber injector is increased to speed up the combustion speed and improve the system power. In the premixed combustion mode, the intake pipe injector is cut off and the main combustion chamber injector is started to change the system combustion mode from premixed combustion to diffusion combustion, thereby increasing the stability of flame propagation and improving the system power.

[0096] In a possible implementation, when the system mode is the energy-saving mode, optimizing the power generation capacity of the jet-ignited free piston power generation system specifically includes:

[0097] The oxygen concentration in the exhaust gas is detected by the oxygen sensor.

[0098] The air-fuel ratio of the jet-ignited free piston power generation system burning in the cylinder is determined according to the oxygen concentration.

[0099] When the air-fuel ratio is lower than the preset air-fuel ratio, the control system is used to control the activation of the first injector, switch the combustion mode to the premixing mode, optimize the power generation capacity of the jet-ignited free piston power generation system, and improve the system economy of the jet-ignited free piston power generation system.

[0100] It should be noted that those skilled in the art can set the preset air-fuel ratio according to actual conditions, and the present invention does not limit this.

[0101] It should be noted that the oxygen sensor is used to detect the exhaust gas oxygen concentration in real time, accurately determine the combustion air-fuel ratio, and adjust the combustion process in time to ensure more complete combustion, achieve lean combustion to reduce fuel consumption, improve system economy and emission performance, and meet energy-saving and environmental protection requirements.

[0102] Specifically, when the system switches to energy-saving mode, good economy is required at this time. The oxygen concentration in the exhaust gas is detected by the oxygen sensor to determine the air-fuel ratio of the current combustion in the cylinder of the system. When the air-fuel ratio is lower than 14.5, the upper computer sends a command to the control ECU to start the pre-combustion chamber injector and reduce the injection pulse width of the main combustion chamber injector to increase the system air-fuel ratio, achieve lean combustion, reduce fuel consumption, improve emissions, and improve system economy.

[0103] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0104] In the present invention, according to the operating state of the jet-ignited free piston power generation system, a control signal is sent through the control system to control the injector, flexibly switching the pre-combustion chamber jet mode and the main combustion chamber combustion mode, thereby improving the combustion efficiency and the system's in-cylinder combustion process, so that the system can better adapt to different working modes, effectively expand the fuel applicability of the free piston internal combustion generator, and promote the application and development of the free piston internal combustion generator technology.

[0105] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0106] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A variable combustion jet ignition free piston power generation system, characterized in that: include: Linear motor, connecting rod assembly, jet-ignited free piston engine, state acquisition system and control system; The linear motor is connected to the jet-ignition free piston engine via a connecting rod assembly; The jet-ignition free piston engine comprises a cylinder (11), a piston (12) and a pre-combustion chamber (13); The air intake pipeline and the main combustion chamber of the cylinder body (11) are respectively equipped with a first fuel injector (9) and a second fuel injector (15); A third fuel injector (17) is installed in the pre-combustion chamber (18); The operating state of the jet-ignited free piston power generation system is collected by the state acquisition system, and the operating state is transmitted to the control system. The control system sends a control signal to control the first injector (9), the second injector (15) and the third injector (17).

2. The variable combustion jet-ignited free piston power generation system according to claim 1, characterized in that: The linear motor comprises a mover (1), a stator (2) and a motor housing (3); A permanent magnet is installed inside the linear motor to generate a magnetic field, driving the mover (1) to perform linear motion.

3. The variable combustion jet-ignited free piston power generation system according to claim 1, characterized in that: The first fuel injector (9) and the second fuel injector (15) are used to adapt to different combustion modes of the jet-ignited free-piston internal combustion generator; The third fuel injector (17) is used to switch the injection mode; A spark plug (19) is installed inside the pre-combustion chamber (13), and the spark plug (19) is used to ignite the mixed gas in the pre-combustion chamber.

4. The variable combustion jet-ignited free piston power generation system according to claim 1, characterized in that: The connecting rod assembly comprises a motor end spring seat (5), a spring (6), a connecting rod (7) and a piston end spring seat (8); The spring (6) is arranged between the motor end spring seat (5) and the piston end spring seat (8), and is sleeved on the connecting rod (7); The two ends of the connecting rod (7) are respectively connected to the mover main shaft (1) and the piston (12) via bolts.

5. The variable combustion jet-ignited free piston power generation system according to claim 1, characterized in that: The state acquisition system comprises a linear motor displacement sensor (4), an in-cylinder pressure sensor (16), a cylinder wall temperature sensor (20) and an oxygen sensor (21); The linear motor displacement sensor (4) is mounted on the motor housing (3) and is used to record position information of the jet-ignited free piston power generation system during operation; The in-cylinder pressure sensor (16) is installed in the top area of ​​the cylinder head of the main combustion chamber of the cylinder body (11) and is used to record the change of gas pressure in the main combustion chamber during the operation of the jet ignition free piston power generation system; The cylinder wall temperature sensor (20) is installed in the middle area of ​​the cylinder head and is used to record the change of the cylinder wall temperature of the jet ignition free piston power generation system during operation; The oxygen sensor (21) is installed in the exhaust pipeline and is used to record the oxygen concentration of the exhaust gas generated by the jet ignition free piston power generation system during operation.

6. The variable combustion jet-ignited free piston power generation system according to claim 1, characterized in that: The control system includes a host computer and a control ECU; The control ECU is connected to the first fuel injector (9), the second fuel injector (15), the third fuel injector (17), the spark plug (19), the state acquisition system and the motor controller respectively through connecting wires; The state acquisition system transmits the acquired data to the host computer, and the host computer analyzes the combustion process in the cylinder according to the acquired data and transmits a control signal to the control ECU.

7. A control method, characterized in that: The variable combustion jet-ignited free piston power generation system applied to any one of claims 1 to 6, the method comprising: S1: collecting the operating status of the jet-ignited free piston power generation system through the status acquisition system; S2: optimizing the power generation capacity of the jet-ignited free piston power generation system in different system modes using the control system according to the operating state; The system modes include normal mode, sports mode and energy-saving mode.

8. The control method according to claim 7, characterized in that: When the system mode is the normal mode, the optimization of the power generation capacity of the jet-ignited free piston power generation system specifically includes: The gas pressure in the cylinder and the system position information of the jet-ignited free piston power generation system are respectively detected by the cylinder pressure sensor and the linear motor displacement sensor; Determining the system output work of the jet-ignited free piston power generation system by means of the gas pressure and the system position information; When the system output power is lower than the preset system output power, the control system is used to control and activate the third injector, and the jet mode is switched to the active jet mode, so as to optimize the power generation capacity of the jet-ignited free piston power generation system and improve the power generation capacity of the jet-ignited free piston power generation system; When the system output power is higher than a preset system output power, the control system is used to control the cutting off of the third injector to avoid the waste of the output power of the jet-ignited free piston power generation system.

9. The control method according to claim 7, characterized in that: When the system mode is the motion mode, the optimization of the power generation capacity of the jet-ignited free piston power generation system specifically includes: Detecting the cylinder wall temperature by the cylinder wall temperature sensor; determining the combustion state in the cylinder according to the cylinder wall temperature; When the cylinder wall temperature is lower than the preset wall temperature, the control system is used to control the activation of the second injector, switch the combustion mode to the diffusion combustion mode, optimize the power generation capacity of the jet-ignited free piston power generation system, and improve the system dynamics of the jet-ignited free piston power generation system.

10. The control method according to claim 7, characterized in that: When the system mode is the energy-saving mode, the optimization of the power generation capacity of the jet-ignited free piston power generation system specifically includes: Detecting the oxygen concentration in the exhaust gas by means of the oxygen sensor; determining an air-fuel ratio of the jet-ignited free piston power generation system burning in the cylinder according to the oxygen concentration; When the air-fuel ratio is lower than a preset air-fuel ratio, the control system is used to control the activation of the first injector, switch the combustion mode to a premixed mode, optimize the power generation capacity of the jet-ignited free piston power generation system, and improve the system economy of the jet-ignited free piston power generation system.

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