Engine control method and engine

Abstract

The invention discloses an engine control method and an engine. The engine control method comprises the steps that according to the residual amount of waste gas in a pre-combustion chamber this time, whether the set starting scavenging crank angle during next scavenging and the set scavenging crank angle variable amount during next scavenging are adjusted or not is determined; starting a scavenging crankshaft rotation angle according to the set scavenging crankshaft rotation angle and the set scavenging crankshaft rotation angle variation during the scavenging; the set limit start scavenging crank angle range and the set limit scavenging crank angle variation range adjust the set start scavenging crank angle during next scavenging and the set scavenging crank angle variation during next scavenging. By adjusting the set starting scavenging crank angle during next scavenging and the set scavenging crank angle variation during next scavenging, the pre-combustion chamber can be accurately and efficiently scavenged subsequently, so that the scavenging quality is effectively improved, and the ignition efficiency and the ignition reliability of igniting fuel gas in the pre-combustion chamber can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of engines, and in particular to an engine control method and an engine. Background Art

[0002] Pre-combustion chamber ignition is one of the main ways to achieve engine ignition. It uses a spark plug in the pre-combustion chamber to ignite the pilot gas, and sprays the ignited high-temperature and high-pressure pilot gas into the main combustion chamber through the channel between the pre-combustion chamber and the main combustion chamber to ignite the gas in the main combustion chamber. This can significantly shorten the combustion duration of the gas in the main combustion chamber, ignite lean gas, reduce combustion temperature, reduce NOx emissions, improve combustion efficiency, and reduce engine gas consumption, etc., so it is widely studied and applied. Specifically, pre-combustion chamber ignition includes active ignition and passive ignition. Active ignition refers to the gas in the pre-combustion chamber being fed from the outside of the engine by an independent pipeline and ignited by a spark plug; passive ignition refers to the gas in the pre-combustion chamber being pressed into the main combustion chamber by a piston and ignited by a spark plug.

[0003] For active ignition, the existing technology usually arranges to scavenge the pre-combustion chamber at the end of the exhaust stage of the main combustion chamber and the intake stage of the main combustion chamber, and injects fuel gas into the pre-combustion chamber during the compression stage of the main combustion chamber. Although it is possible to ignite the fuel gas in the main combustion chamber, the scavenging quality and scavenging efficiency of the pre-combustion chamber, and the ignition efficiency and ignition reliability of igniting the fuel gas in the pre-combustion chamber all need to be improved. Summary of the invention

[0004] The object of the present invention is to provide an engine control method and an engine to solve the above-mentioned problems existing in the active ignition in the prior art.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] An engine control method, wherein the engine includes a pre-combustion chamber structure, wherein the pre-combustion chamber structure includes a pre-combustion chamber body, and the pre-combustion chamber body is provided with a pre-combustion chamber; the engine control method includes:

[0007] Determine whether to adjust the set start scavenging crank angle at the next scavenging and the set scavenging crank angle change at the next scavenging according to the residual exhaust gas amount in the pre-combustion chamber at this time;

[0008] The set start scavenging crank angle for the next scavenging and the set scavenging crank angle change for the next scavenging are adjusted based on the set start scavenging crank angle for the current scavenging, the set scavenging crank angle change for the current scavenging, the set limit start scavenging crank angle range and the set limit scavenging crank angle change range.

[0009] As a preferred embodiment of the above engine control method, the step of determining whether to adjust the set start scavenging crank angle and the set scavenging crank angle change amount at the next scavenging according to the residual exhaust gas amount in the current pre-combustion chamber includes:

[0010] Determine whether the mass fraction of the remaining exhaust gas in the pre-combustion chamber is less than the set exhaust gas mass fraction;

[0011] If the mass fraction of the residual exhaust gas in the pre-combustion chamber this time is less than the set exhaust gas mass fraction, the set scavenging crank angle at the next start of scavenging is kept equal to the set scavenging crank angle at the current start of scavenging, and the set scavenging crank angle change at the next scavenging is kept equal to the set scavenging crank angle change at the current scavenging;

[0012] If the mass fraction of the remaining exhaust gas in the pre-combustion chamber is greater than or equal to the set exhaust gas mass fraction, the set start scavenging crankshaft angle for the next scavenging and the set scavenging crankshaft angle change for the next scavenging are adjusted.

[0013] As a preferred embodiment of the above-mentioned engine control method, the step of adjusting the set start scavenging crank angle for the next scavenging and the set scavenging crank angle change amount for the next scavenging according to the set start scavenging crank angle for the current scavenging, the set scavenging crank angle change amount for the current scavenging, the set limit start scavenging crank angle range and the set limit scavenging crank angle change amount range comprises:

[0014] Determine whether (the set start scavenging crank angle at this scavenging time + M°CA) is less than or equal to the minimum value of the set limit start scavenging crank angle range; wherein 0>M≥-5;

[0015] If (the set starting scavenging crankshaft angle for this scavenging + M°CA) is greater than the minimum value of the set limit starting scavenging crankshaft angle range and is less than or equal to the maximum value of the set limit starting scavenging crankshaft angle range, then the set starting scavenging crankshaft angle for the next scavenging is adjusted to = the set starting scavenging crankshaft angle for this scavenging + M°CA.

[0016] As a preferred solution of the above engine control method, if (the set scavenging crank angle at the start of scavenging + M°CA) is less than or equal to the minimum value of the set limit scavenging crank angle range, then it is determined whether (the set scavenging crank angle change at the start of scavenging + N°CA) is greater than or equal to the maximum value of the set limit scavenging crank angle change range; wherein 0<N≤5;

[0017] If (the set scavenging crank angle change during this scavenging + N°CA) is greater than or equal to the minimum value of the set limit scavenging crank angle change range and is less than the maximum value of the set limit scavenging crank angle change range, then the set scavenging crank angle change during the next scavenging is adjusted to = the set scavenging crank angle change during this scavenging + N°CA.

[0018] As a preferred solution of the above engine control method, the crankshaft angle range for starting scavenging at the limit is: -360°CA to -300°CA;

[0019] The range of the set limit scavenging crank angle variation is: 40°CA~80°CA.

[0020] As a preferred solution of the above engine control method, the pre-combustion chamber body is provided with an active gas channel connected to the pre-combustion chamber, and the input end of the active gas channel can be selectively connected to a gas source; the engine control method further includes:

[0021] After the scavenging is finished, when the crankshaft angle rotates to the set combustion start crankshaft angle, the active gas channel and the gas source are connected, and the gas source is synchronously controlled to deliver gas to the active gas channel;

[0022] disconnecting the active fuel gas passage and the fuel gas source according to the set fuel gas crank angle change during the current fuel gas intake;

[0023] The set combustion crank angle change for the next combustion process is adjusted based on the mass fraction of the combustion gas in the pre-combustion chamber during this ignition, the set combustion crank angle change for this combustion process, and the set limit combustion crank angle change range.

[0024] As a preferred embodiment of the above-mentioned engine control method, the step of adjusting the set combustion crank angle change amount for the next combustion injection according to the mass fraction of the combustion gas in the pre-combustion chamber at the current ignition, the set combustion crank angle change amount for the current combustion injection and the set limit combustion crank angle change amount range comprises:

[0025] Determine whether the mass fraction of the gas in the pre-combustion chamber during this ignition is within the set gas mass fraction range;

[0026] If the mass fraction of the gas in the pre-combustion chamber during this ignition is within the set gas mass fraction range, the set crank angle change during the next gas injection is kept equal to the set crank angle change during this gas injection;

[0027] If the mass fraction of the gas in the pre-combustion chamber during this ignition is less than the minimum value of the set gas mass fraction range, it is determined whether (the set combustion crank angle change during this combustion + L°CA) is within the set limit combustion crank angle change range; wherein 0<L≤5;

[0028] If (the set crank angle change amount for this gas injection + L°CA) is within the set limit crank angle change amount range, then the set crank angle change amount for the next gas injection is adjusted to be the set crank angle change amount for this gas injection + L°CA;

[0029] If the mass fraction of the gas in the pre-combustion chamber during this ignition is greater than the maximum value of the set gas mass fraction range, it is determined whether (the set combustion crank angle change during this combustion - L°CA) is within the set limit combustion crank angle change range;

[0030] If (the set crank angle change during this gas intake - L°CA) is within the set limit crank angle change range, then the set crank angle change during the next gas intake is adjusted to = the set crank angle change during this gas intake - L°CA.

[0031] As a preferred solution of the above engine control method, the range of the set limit combustion crankshaft angle change is: 40°CA~100°CA.

[0032] As a preferred solution of the above engine control method, the pre-combustion chamber body is further provided with an active scavenging channel connected to the pre-combustion chamber, and the input end of the active scavenging channel can be selectively connected to a scavenging air source;

[0033] Before determining whether to adjust the set start scavenging crank angle for the next scavenging and the set scavenging crank angle change amount for the next scavenging according to the residual exhaust gas amount in the current pre-combustion chamber, the following steps are also included:

[0034] Connecting the input end of the active scavenging channel with the scavenging gas source according to the scavenging crankshaft angle set at the time of the current scavenging, and synchronously controlling the scavenging gas source to deliver gas to the active scavenging channel for scavenging;

[0035] The input end of the active scavenging passage and the scavenging gas source are disconnected according to the set scavenging crankshaft angle change during the current scavenging to end the scavenging.

[0036] An engine comprises a pre-combustion chamber structure, wherein the pre-combustion chamber structure comprises a pre-combustion chamber body, and the pre-combustion chamber body is provided with a pre-combustion chamber; and is used to execute the above-mentioned engine control method.

[0037] Beneficial effects of the present invention:

[0038] The present invention discloses an engine control method and an engine. The engine control method includes: determining whether to adjust the set start scavenging crank angle and the set scavenging crank angle change amount at the next scavenging according to the residual amount of exhaust gas in the current pre-combustion chamber; adjusting the set start scavenging crank angle and the set scavenging crank angle change amount at the next scavenging according to the set start scavenging crank angle at the current scavenging, the set scavenging crank angle change amount at the current scavenging, the set limit start scavenging crank angle range and the set limit scavenging crank angle change amount range.

[0039] By adjusting the set starting scavenging crankshaft angle at the next scavenging and the set scavenging crankshaft angle change at the next scavenging, the pre-combustion chamber can be scavenged accurately and efficiently subsequently, so that the scavenging quality can be effectively improved, thereby effectively reducing the risk of gas leakage from the pre-combustion chamber into the main combustion chamber of the engine, so that the ignition efficiency and ignition reliability of the gas in the pre-combustion chamber can be effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a structural schematic diagram of a pre-combustion chamber structure provided by a specific embodiment of the present invention;

[0041] Figure 2 yes Figure 1 Section view along AA;

[0042] Figure 3 yes Figure 1 Cross-section along BB Figure 1 ;

[0043] Figure 4 yes Figure 1 Cross-section along BB Figure 2 ;

[0044] Figure 5 yes Figure 2 Sectional view along CC;

[0045] Figure 6 The process of the engine control method provided by the specific embodiment of the present invention is Figure 1 ;

[0046] Figure 7 The process of the engine control method provided by the specific embodiment of the present invention is Figure 2 ;

[0047] Figure 8 The process of the engine control method provided by the specific embodiment of the present invention is Figure 3 ;

[0048] Fig. 9The process of the engine control method provided by the specific embodiment of the present invention is Figure 4 ;

[0049] Fig.10 The process of the engine control method provided by the specific embodiment of the present invention is Figure 5 ;

[0050] Fig.11 is a curve diagram formed by the excess air coefficient in the pre-combustion chamber and the crankshaft angle provided by a specific embodiment of the present invention;

[0051] Fig.12 It is a curve diagram formed by the mass fraction of the fuel gas in the pre-combustion chamber and the crankshaft angle provided by a specific embodiment of the present invention.

[0052] In the figure:

[0053] 1. Pre-combustion chamber body; 11. Pre-combustion chamber; 111. First sub-chamber; 112. Second sub-chamber; 12. Central mounting hole; 13. Ventilation hole; 14. Active scavenging channel; 141. Sub-scavenging channel; 142. Annular scavenging channel; 15. Active gas channel; 151. Sub-gas channel; 152. Annular gas channel;

[0054] 2. Control valve block;

[0055] 3. Air intake manifold;

[0056] 4. Intake branch pipe. DETAILED DESCRIPTION

[0057] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0058] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0059] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0060] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0061] The present invention provides an engine, including a pre-combustion chamber structure. Figure 1-4 As shown, the pre-combustion chamber structure includes a pre-combustion chamber body 1, and the pre-combustion chamber body 1 is provided with a pre-combustion chamber 11. Gas is introduced into the pre-combustion chamber 11, and the gas in the pre-combustion chamber 11 is ignited, so that the gas in the main combustion chamber of the engine can be ignited, and active ignition is achieved, so that the engine can work normally and orderly.

[0062] Specifically, Figure 2-4 As shown, the top of the pre-combustion chamber body 1 is provided with a central mounting hole 12 connected to the pre-combustion chamber 11, and the central mounting hole 12 is used to install a spark plug so as to ignite the gas in the pre-combustion chamber 11. Preferably, the central axis of the central mounting hole 12 is colinear with the central axis of the pre-combustion chamber 11.

[0063] Specifically, Figure 1-5 As shown, the bottom of the pre-combustion chamber body 1 is provided with a vent hole 13 connected to the pre-combustion chamber 11. The vent hole 13 is connected to the main combustion chamber of the engine. During scavenging, the exhaust gas in the pre-combustion chamber 11 flows to the main combustion chamber through the vent hole 13 and flows out of the main combustion chamber. During ignition, the ignited gas in the pre-combustion chamber 11 is sprayed into the main combustion chamber through the vent hole 13, which can ignite the gas in the main combustion chamber to achieve active ignition.

[0064] Preferably, the number of the vent holes 13 is multiple, and the multiple vent holes 13 are spaced apart along the circumference of the pre-combustion chamber 11 to improve the uniformity of gas injection and the efficiency and reliability of igniting the gas in the main combustion chamber. Further preferably, the multiple vent holes 13 are spaced apart evenly along the circumference of the pre-combustion chamber 11 to further improve the uniformity of gas injection.

[0065] Among them, Figure 2-4 As shown, the pre-combustion chamber body 1 is also provided with an active scavenging passage 14 communicating with the pre-combustion chamber 11, and an active fuel gas passage 15 communicating with the pre-combustion chamber 11. Along the height direction of the pre-combustion chamber 11, the active fuel gas passage 15 is located below the active scavenging passage 14. The pre-combustion chamber structure also includes a control valve block 2, which can selectively connect and disconnect the input end of the active scavenging passage 14 and the scavenging gas source, and can selectively connect and disconnect the input end of the active fuel gas passage 15 and the fuel gas source.

[0066] When the pre-combustion chamber 11 is scavenged, the input end of the active scavenging channel 14 is controlled by the control valve block 2 to be connected to the scavenging gas source, and the input end of the active gas channel 15 is disconnected from the gas source. When gas is introduced into the pre-combustion chamber 11, the input end of the active scavenging channel 14 is controlled by the control valve block 2 to be disconnected from the scavenging gas source, and the input end of the active gas channel 15 is connected to the gas source. When the pre-combustion chamber 11 is not scavenged and gas is not introduced, the input end of the active scavenging channel 14 is controlled by the control valve block 2 to be disconnected from the scavenging gas source, and the input end of the active gas channel 15 is disconnected from the gas source. This arrangement makes the active scavenging of the pre-combustion chamber 11 and the active gas injection of the pre-combustion chamber 11 independent of each other and do not interfere with each other, which is convenient for adjusting the start time of the active scavenging and the start time of the active gas injection. Secondly, along the height direction of the pre-combustion chamber 11, an active gas channel 15 is arranged below the active scavenging channel 14, so that the active scavenging channel 14 is close to the top of the pre-combustion chamber body 1 relative to the active gas channel 15, so that when gas is introduced into the pre-combustion chamber 11 through the active scavenging channel 14, the effect and efficiency of scavenging the pre-combustion chamber 11 can be effectively improved. In addition, when gas is introduced into the pre-combustion chamber 11 through the active gas channel 15, the introduced gas can also further purge the pre-combustion chamber 11, thereby further improving the effect and efficiency of scavenging the pre-combustion chamber 11, so as to effectively reduce the risk of gas in the pre-combustion chamber 11 leaking into the main combustion chamber of the engine.

[0067] Specifically, in the present embodiment, the control valve block 2 includes two switch valves. The two switch valves include a first switch valve and a second switch valve. The input end of the first switch valve is connected to the scavenging air source, and the output end of the first switch valve is connected to the input end of the active scavenging channel 14 through one of its intake branches 4. The input end of the second switch valve is connected to the fuel gas source, and the output end of the second switch valve is connected to the input end of the active fuel gas channel 15 through another intake branch 4. As an alternative, the control valve block 2 may also be an electromagnetic reversing valve. It can selectively switch on and off the input end of the active scavenging channel 14 and the scavenging air source, and can selectively switch on and off the input end of the active fuel gas channel 15 and the fuel gas source. Exemplarily, the electromagnetic reversing valve is a three-position four-way electromagnetic reversing valve.

[0068] Specifically, Figure 2-4 As shown, the active scavenging channel 14 includes a sub-scavenging channel group, and the sub-scavenging channel group includes a plurality of sub-scavenging channels 141 distributed at intervals along the circumference of the pre-combustion chamber 11. The angle between the direction in which the gas flows from the sub-scavenging channel 141 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is a first angle, and the first angle is greater than 90° and less than 180°. In this way, the gas injected into the pre-combustion chamber 11 from each sub-scavenging channel 141 along the height direction of the pre-combustion chamber 11 is inclined downward, which helps to discharge the exhaust gas generated in the previous cycle in the pre-combustion chamber 11, so that the scavenging effect of the pre-combustion chamber 11 can be effectively improved, thereby effectively reducing the risk of gas leakage from the pre-combustion chamber 11 into the main combustion chamber, and improving the working performance of the pre-combustion chamber structure.

[0069] Preferably, if Figure 2-4As shown, the number of sub-scavenging channel groups is multiple, and the multiple sub-scavenging channel groups are spaced along the height direction of the pre-combustion chamber 11. Along the direction from top to bottom of the pre-combustion chamber 11, the first angles corresponding to the multiple sub-scavenging channel groups gradually increase. The number of sub-scavenging channel groups is set to be multiple, and the multiple sub-scavenging channel groups are spaced along the height direction of the pre-combustion chamber 11, so that the coverage area of ​​the active scavenging channel 14 is large, which can further improve the scavenging effect and scavenging efficiency of scavenging the pre-combustion chamber 11, thereby further reducing the risk of gas leakage in the pre-combustion chamber 11 into the main combustion chamber, and further improving the working performance of the pre-combustion chamber structure; secondly, the first angles corresponding to the multiple sub-scavenging channel groups are set to gradually increase along the direction from top to bottom of the pre-combustion chamber 11, so that the gas injected into the central area of ​​the pre-combustion chamber 11 by the sub-scavenging channel groups is distributed in sequence from top to bottom along the height direction of the pre-combustion chamber 11, thereby further improving the scavenging effect and scavenging efficiency of scavenging the pre-combustion chamber 11. Among them, the central area of ​​the pre-combustion chamber 11 refers to the area where the central axis of the pre-combustion chamber 11 is located. It can be understood that the direction from top to bottom of the pre-combustion chamber 11, the direction from bottom to top of the pre-combustion chamber 11, the height direction of the pre-combustion chamber 11 and the central axis of the pre-combustion chamber 11 are all parallel.

[0070] Preferably, if Figure 2-4 As shown, a plurality of sub-scavenging channel groups are evenly spaced and distributed along the height direction of the pre-combustion chamber 11. A plurality of sub-scavenging channels 141 of each sub-scavenging channel group are evenly spaced and distributed along the circumference of the pre-combustion chamber 11. In this embodiment, two sub-scavenging channel groups are provided as an example, and each sub-scavenging channel group includes five sub-scavenging channels 141 evenly spaced and distributed along the circumference of the pre-combustion chamber 11.

[0071] Preferably, if Figure 2-4 As shown, in two adjacent sub-scavenging channel groups along the height direction of the pre-combustion chamber 11, the multiple sub-scavenging channels 141 in one sub-scavenging channel group and the multiple sub-scavenging channels 141 in the other sub-scavenging channel group are staggered in the circumferential arrangement of the pre-combustion chamber 11. The scavenging range of the active scavenging channel 14 can be further increased, thereby further improving the scavenging effect and scavenging efficiency of the pre-combustion chamber 11. As an alternative, in two adjacent sub-scavenging channel groups along the height direction of the pre-combustion chamber 11, the multiple sub-scavenging channels 141 in one sub-scavenging channel group correspond one-to-one with the multiple sub-scavenging channels 141 in the other sub-scavenging channel group and have the same circumferential arrangement position of the pre-combustion chamber 11.

[0072] Preferably, if Figure 2-4As shown, the sub-scavenging channel 141 is arc-shaped; along the height direction of the pre-combustion chamber 11, the arc-shaped opening faces downward. So that along the height direction of the pre-combustion chamber 11, the gas sprayed into the pre-combustion chamber 11 from each sub-scavenging channel 141 is inclined downward, so as to help discharge the exhaust gas generated in the previous cycle in the pre-combustion chamber 11. As an alternative, the sub-scavenging channel 141 can also be set to be linear, and the angle between the direction of the gas flowing from the linear sub-scavenging channel 141 to the pre-combustion chamber 11 and the direction of the pre-combustion chamber 11 from top to bottom is greater than or equal to 90° and less than 180°. Along the height direction of the pre-combustion chamber 11, the gas sprayed into the pre-combustion chamber 11 from each sub-scavenging channel 141 can also be inclined downward, so as to help discharge the exhaust gas generated in the previous cycle in the pre-combustion chamber 11.

[0073] Preferably, the aperture of the sub-scavenging channel 141 gradually decreases from the input end of the sub-scavenging channel 141 to the output end of the sub-scavenging channel 141. It is understandable that the cross-sectional area of ​​the sub-scavenging channel 141 perpendicular to its own extension direction gradually decreases from the input end of the sub-scavenging channel 141 to the output end of the sub-scavenging channel 141. This can effectively increase the speed at which the gas is sprayed from the sub-scavenging channel 141 into the pre-combustion chamber 11, thereby further improving the scavenging effect and scavenging efficiency of the pre-combustion chamber 11. As an alternative, the apertures of the sub-scavenging channel 141 are equal at various locations along the input end of the sub-scavenging channel 141 to the output end of the sub-scavenging channel 141.

[0074] Specifically, Figure 2-4 As shown, the active scavenging channel 14 further includes an annular scavenging channel 142 located in the pre-combustion chamber body 1, and the annular scavenging channel 142 is connected to each sub-scavenging channel 141 of each sub-scavenging channel group, and is connected to one output end of the control valve block 2. This enables one end of each sub-scavenging channel 141 to be connected and selectively connected to the scavenging gas source.

[0075] Specifically, in this embodiment, the gas supplied by the scavenging gas source is fuel gas, and the fuel gas is methane. The fuel gas supplied by the fuel gas source is also methane. As an alternative, the gas supplied by the scavenging gas source is air. In other embodiments, the fuel gas can also be replaced by hydrogen or other hydrocarbons.

[0076] Specifically, Figure 2-4As shown, the active scavenging channel 14 includes a sub-gas channel group, and the sub-gas channel group includes a plurality of sub-gas channels 151 distributed at intervals along the circumference of the pre-combustion chamber 11. One end of each sub-gas channel 151 is connected to the other output end of the control valve block 2, and the other end of each sub-gas channel 151 is connected to the pre-combustion chamber 11. The angle between the direction in which the gas flows from the sub-gas channel 151 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is a second angle, and the second angle is less than or equal to 90°. The angle between the direction in which the gas flows from the sub-gas channel 151 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is the second angle. When the second angle is less than 90°, the gas injected into the pre-combustion chamber 11 from each sub-scavenging channel 141 along the height direction of the pre-combustion chamber 11 is inclined upward, so that the gas can accumulate upward along the height direction of the pre-combustion chamber 11 near the spark plug, so that the gas around the spark plug can be as concentrated as possible, and the exhaust gas generated in the previous cycle in the pre-combustion chamber 11 can be further discharged by using the inclined upward injection of the gas, which is beneficial to improving the ignition efficiency and ignition reliability of the ignition of the gas in the pre-combustion chamber 11; when the angle between the direction in which the gas flows from the sub-gas channel 151 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is equal to 90°, the gas injected in the horizontal direction can make the gas in the pre-combustion chamber 11 mixed more evenly, which is beneficial to the ignition of the gas in the current cycle.

[0077] Preferably, if Figure 2-4 As shown, there are multiple sub-gas channel groups, and the multiple sub-gas channel groups are spaced apart along the height direction of the pre-combustion chamber 11. Along the direction from top to bottom of the pre-combustion chamber 11, the second angles corresponding to the multiple sub-gas channel groups gradually increase. The number of sub-gas channel groups is set to be multiple, and the multiple sub-gas channel groups are spaced apart along the height direction of the pre-combustion chamber 11, so that the coverage area of ​​the active gas channel 15 is large, thereby further improving the mixing uniformity of the gas in the pre-combustion chamber 11; secondly, the second angles corresponding to the multiple sub-gas channel groups are set to gradually increase along the direction from top to bottom of the pre-combustion chamber 11, so that the gas injected into the central area of ​​the pre-combustion chamber by the sub-gas channel groups is distributed in sequence from top to bottom along the height direction of the pre-combustion chamber, thereby further improving the mixing uniformity of the gas in the pre-combustion chamber 11.

[0078] Preferably, if Figure 2-4 As shown, a plurality of sub-gas channel groups are evenly spaced and distributed along the height direction of the pre-combustion chamber 11. The sub-gas channels 151 in each sub-gas channel group are evenly spaced and distributed along the circumference direction of the pre-combustion chamber 11.

[0079] Preferably, the sub-gas channel 151 is in a straight line, and the angle between the direction of gas flowing from the straight sub-gas channel 151 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is less than or equal to 90°. This allows the gas to quickly and efficiently accumulate in the top center area of ​​the pre-combustion chamber 11, thereby further facilitating the improvement of the ignition efficiency and ignition reliability of the gas in the pre-combustion chamber 11.

[0080] Specifically, Figure 2-4 As shown, the active gas channel 15 further includes an annular gas channel 152 located in the pre-combustion chamber body 1, and the annular gas channel 152 is connected to each sub-gas channel 151 of each sub-gas channel group, and is connected to the other output end of the control valve block 2. This enables one end of each sub-gas channel 151 to be connected and selectively connected to the gas source.

[0081] Preferably, if Figure 2-4 As shown, the pre-combustion chamber 11 includes a conical first sub-chamber 111 and a cylindrical second sub-chamber 112; along the height direction of the pre-combustion chamber 11, the first sub-chamber 111 is located above the second sub-chamber 112, and the small end of the first sub-chamber 111 is connected to the second sub-chamber 112. For the plurality of sub-gas channel groups located in the area where the first sub-chamber 111 is located, the angle between the direction in which the gas flows from the sub-gas channel 151 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is less than 90°; for the plurality of sub-gas channel groups located in the area where the second sub-chamber 112 is located, the angle between the direction in which the gas flows from the sub-gas channel 151 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is equal to 90°. In this way, the plurality of sub-gas channel groups located in the area where the first sub-chamber 111 is located can make the gas accumulate upward in the vicinity of the spark plug along the height direction of the pre-combustion chamber 11, so that the gas around the spark plug is as dense as possible, and the plurality of sub-gas channel groups located in the area where the second sub-chamber 112 is located can make the gas in the pre-combustion chamber 11 mixed more evenly, which is conducive to the ignition of the gas in the current cycle. In this way, the ignition efficiency of the gas in the pre-combustion chamber 11 can be effectively improved, and the mixing uniformity of the gas in the pre-combustion chamber 11 can be effectively improved.

[0082] Specifically, in this embodiment, Figure 2-4 As shown, along the height direction of the pre-combustion chamber 11, the central mounting hole 12 and the multiple sub-scavenging channels 141 of the active scavenging channel 14 are all located at the top of the first sub-chamber 111 and are all connected to the first sub-chamber 111. The vent hole 13 is located at the bottom of the second sub-chamber 112 and is connected to the second sub-chamber 112.

[0083] In this embodiment, if Figure 2-4As shown, five sub-gas channel groups are exemplarily set, and the five sub-gas channel groups are evenly spaced and distributed along the height direction of the pre-combustion chamber 11. Two of the sub-gas channel groups are located in the area where the first sub-chamber 111 is located, and the remaining three sub-gas channel groups are located in the area where the second sub-chamber 112 is located. Specifically, for the two sub-gas channel groups located in the area where the first sub-chamber 111 is located, the angle between the direction in which the gas flows from the sub-gas channel 151 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is less than 90°; and along the direction from top to bottom of the pre-combustion chamber 11, the corresponding angles of the two sub-gas channel groups gradually increase. For the three sub-gas channel groups located in the area where the second sub-chamber 112 is located, the angle between the direction in which the gas flows from the sub-gas channel 151 to the pre-combustion chamber 11 and the direction from top to bottom of the pre-combustion chamber 11 is equal to 90°.

[0084] In this embodiment, each sub-gas channel group is exemplarily configured to include five sub-gas channels 151 , and the five sub-gas channels 151 of each sub-gas channel group are evenly spaced and distributed along the circumference of the pre-combustion chamber 11 .

[0085] Specifically, Figure 1-4 As shown, the pre-combustion chamber structure also includes an intake manifold 3 , the input end of the intake manifold 3 is used to communicate with the scavenging air source and the fuel gas source, and the output end of the intake manifold 3 is communicated with the input end of the control valve block 2 .

[0086] In this embodiment, the scavenging gas source and the fuel gas source are the same supply gas source. The input end of the intake manifold 3 is connected to the supply gas source. As an alternative, the intake manifold 3 is provided with two inlets, one of which is connected to the scavenging gas source and the other is connected to the fuel gas source.

[0087] Preferably, the sum of the end surface areas of the output ends of the sub-scavenging channels 141 is equal to the intake cross-sectional area of ​​the intake manifold 3 perpendicular to its own extending direction, so as to avoid pressure loss caused by the conveying gas.

[0088] Preferably, the sum of the end surface areas of the output ends of the sub-gas channels 151 is equal to the intake cross-sectional area of ​​the intake manifold 3 perpendicular to its own extension direction, so as to avoid pressure loss caused by transporting gas.

[0089] The present invention also provides an engine control method for implementing the above engine. By adopting the engine control method, the scavenging quality of the pre-combustion chamber 11 can be effectively improved, and the ignition efficiency and ignition reliability of the gas in the pre-combustion chamber 11 can be effectively improved.

[0090] like Figure 6-9 As shown, the engine control method includes:

[0091] S100, starting the scavenging crank angle to connect the input end of the active scavenging channel 14 with the scavenging gas source according to the setting during the current scavenging, and synchronously controlling the scavenging gas source to transport gas to the active scavenging channel 14 for scavenging.

[0092] Specifically, step S100 includes:

[0093] It is determined whether the current crankshaft angle is the set start scavenging crankshaft angle for this scavenging.

[0094] If the current crankshaft angle is the set scavenging crankshaft angle for starting scavenging during this scavenging, the input end of the active scavenging channel 14 is connected to the scavenging gas source, and the scavenging gas source is synchronously controlled to deliver gas to the scavenging channel 14 for scavenging, so that the time when the pre-combustion chamber 11 starts scavenging can be accurately controlled.

[0095] The set start scavenging crank angle at the first scavenging is the best scavenging crank angle determined when the engine was last operated. Alternatively, the set start scavenging crank angle at the first scavenging is an empirical value obtained from a large number of previous tests. The set start scavenging crank angle corresponds to the end of the engine being in the intake phase or the exhaust phase. In this embodiment, the set start scavenging crank angle at the first scavenging is exemplified as -320°CA.

[0096] S200, disconnecting the input end of the active scavenging channel 14 and the scavenging gas source according to the set scavenging crankshaft angle change during the current scavenging to end the scavenging.

[0097] Specifically, step S200 includes:

[0098] Determine whether the crank angle change after the start of scavenging reaches the set scavenging crank angle change during this scavenging. If the crank angle change after the start of scavenging reaches the set scavenging crank angle change during this scavenging, disconnect the input end of the active scavenging channel 14 and the scavenging air source to end the scavenging. Specifically, at this time, control the control valve block 2 to disconnect the input end of the active scavenging channel 14 and the scavenging air source. This allows the precise control of the moment when the pre-combustion chamber 11 ends scavenging. In this embodiment, the set scavenging crank angle change of 60°CA during the first scavenging is taken as an example.

[0099] It can be understood that, during the execution of steps S100 and S200 , the input end of the active gas channel 15 and the gas source are always kept disconnected by controlling the valve block 2 .

[0100] Specifically, during the execution of steps S100 and S200, the total amount of scavenging injection is monitored synchronously. The total amount of scavenging injection is always kept less than or equal to 1% of the total amount of gas. The total amount of gas refers to the total amount of gas introduced into the pre-combustion chamber 11 and the main combustion chamber of the engine this time. For the scavenging gas being air, too much total amount of air injection is not conducive to the subsequent ignition of the gas in the pre-combustion chamber 11; for the scavenging gas being fuel gas, too much total amount of gas injection is not conducive to energy saving. In this embodiment, the scavenging gas is exemplarily set to fuel gas. Therefore, further, the total amount of scavenging injection is obtained by monitoring the fuel gas quality sensor; or, the scavenging concentration is obtained by monitoring the fuel gas concentration sensor, and the total amount of gas injection is calculated based on the fuel gas concentration. The specific calculation method for calculating the total amount of fuel injection based on the fuel gas concentration belongs to the prior art and will not be repeated here.

[0101] Specifically, while disconnecting the input end of the active scavenging channel 14 and the scavenging gas source, monitor the amount of residual exhaust gas in the current pre-combustion chamber 11, and then execute step S300. Further, while disconnecting the input end of the active scavenging channel 14 and the scavenging gas source, execute step S500. It can be understood that regardless of whether the set start scavenging crank angle at the next scavenging and the set scavenging crank angle change at the next scavenging are adjusted, a series of actions after the current scavenging are performed normally.

[0102] Further, the remaining exhaust gas volume is obtained by monitoring a mass sensor; or, the remaining exhaust gas concentration is obtained by monitoring a concentration sensor, and then the remaining exhaust gas volume is calculated based on the remaining exhaust gas concentration. The specific calculation method for calculating the remaining exhaust gas volume based on the remaining exhaust gas concentration belongs to the prior art and will not be repeated here. Further, in this embodiment, the exhaust gas mainly includes carbon dioxide. Therefore, the remaining exhaust gas volume is monitored by a carbon dioxide mass sensor; or, the remaining carbon dioxide concentration is obtained by monitoring a carbon dioxide concentration sensor, and then the remaining carbon dioxide volume is calculated based on the remaining carbon dioxide concentration.

[0103] S300, determining whether to adjust the set scavenging crank angle for the start of next scavenging and the set scavenging crank angle change amount for the next scavenging based on the remaining amount of exhaust gas in the pre-combustion chamber 11 at this time.

[0104] Specifically, Figure 6-8 As shown, step S300 includes:

[0105] S310, calculating the mass fraction of the remaining exhaust gas in the pre-combustion chamber 11 according to the remaining exhaust gas amount in the pre-combustion chamber 11. The specific calculation method for calculating the mass fraction of the remaining exhaust gas in the pre-combustion chamber 11 according to the remaining exhaust gas amount in the pre-combustion chamber 11 belongs to the prior art and will not be described in detail here.

[0106] S320, judging whether the mass fraction of the remaining exhaust gas in the pre-combustion chamber 11 is less than the set exhaust gas mass fraction.

[0107] If the mass fraction of the remaining exhaust gas in the pre-combustion chamber 11 is less than the set exhaust gas mass fraction, step S330 is executed.

[0108] S330, maintaining the set scavenging crank angle for the next scavenging start equal to the set scavenging crank angle for the current scavenging start, and maintaining the set scavenging crank angle change for the next scavenging equal to the set scavenging crank angle change for the current scavenging.

[0109] If the mass fraction of the remaining exhaust gas in the pre-combustion chamber 11 is greater than or equal to the set exhaust gas mass fraction, step S340 is executed.

[0110] S340, adjusting the set scavenging crank angle for starting the next scavenging and the set scavenging crank angle change for the next scavenging.

[0111] Among them, the exhaust gas mass fraction is set based on the empirical value obtained from a large number of previous tests.

[0112] Specifically, if the mass fraction of the residual exhaust gas in the pre-combustion chamber 11 is less than the set exhaust gas mass fraction, it means that at the end of scavenging, the residual amount of exhaust gas in the pre-combustion chamber 11 is small. According to the set starting scavenging crankshaft angle at the start of this scavenging and the set scavenging crankshaft angle change at this scavenging, the exhaust gas in the pre-combustion chamber 11 can be cleaned accurately and efficiently, thereby eliminating the need to adjust the set starting scavenging crankshaft angle at the next scavenging and the set scavenging crankshaft angle change at the next scavenging.

[0113] Specifically, if the mass fraction of the residual exhaust gas in the pre-combustion chamber 11 is greater than or equal to the set exhaust gas mass fraction, it indicates that a large amount of exhaust gas still remains in the pre-combustion chamber 11 at the end of scavenging, and it is necessary to adjust the set start scavenging crank angle at the next scavenging and the set scavenging crank angle change at the next scavenging, so that the pre-combustion chamber 11 can be scavenged accurately and efficiently in the future, thereby effectively improving the scavenging quality. It is understandable that when the scavenging quality is improved, the residual exhaust gas in the pre-combustion chamber 11 is less, thereby effectively reducing the risk of gas leakage from the pre-combustion chamber 11 to the main combustion chamber of the engine, thereby effectively improving the ignition efficiency and ignition reliability of igniting the gas in the pre-combustion chamber 11.

[0114] Specifically, in this embodiment, the exhaust gas mass fraction is set to 0.04. The exhaust gas mass fraction is set to an empirical value obtained from a large number of previous tests.

[0115] S400, adjusting the set start scavenging crank angle for next scavenging and the set scavenging crank angle change for next scavenging according to the set start scavenging crank angle for this scavenging, the set scavenging crank angle change for this scavenging, the set limit start scavenging crank angle range and the set limit scavenging crank angle change range.

[0116] Specifically, Figure 6 , Figure 7 and Fig. 9 As shown, step S400 includes:

[0117] S410: Determine whether (the set scavenging start crank angle + M°CA for this scavenging) is less than or equal to the minimum value of the set limit scavenging start crank angle range, where 0>M≥-5.

[0118] If (the set start scavenging crank angle during this scavenging + M°CA) is greater than the minimum value of the set limit start scavenging crank angle range and is less than or equal to the maximum value of the set limit start scavenging crank angle range, execute step S420.

[0119] S420, adjusting the set scavenging start crank angle for the next scavenging = the set scavenging start crank angle for the current scavenging + M°CA.

[0120] If (the set scavenging start crank angle during the current scavenging + M°CA) is less than or equal to the minimum value of the set limit scavenging start crank angle range, step S430 is executed.

[0121] S430: Determine whether (the set scavenging crank angle variation amount during the current scavenging + N°CA) is greater than or equal to the maximum value of the set limit scavenging crank angle variation amount range, where 0<N≤5.

[0122] If (the set scavenging crank angle change amount during this scavenging + N°CA) is greater than or equal to the minimum value of the set limit scavenging crank angle change amount range and less than the maximum value of the set limit scavenging crank angle change amount range, execute step S440.

[0123] S440, adjusting the set scavenging crank angle change amount for the next scavenging=the set scavenging crank angle change amount for the current scavenging+N°CA.

[0124] Specifically, when the mass fraction of the remaining exhaust gas in the pre-combustion chamber 11 is greater than or equal to the set exhaust gas mass fraction, if (the set starting scavenging crankshaft angle at this scavenging + M°CA) is greater than the minimum value of the set limit starting scavenging crankshaft angle range and is less than or equal to the maximum value of the set limit starting scavenging crankshaft angle range, then the set starting scavenging crankshaft angle at the next scavenging is reduced to advance the start time corresponding to the set starting scavenging crankshaft angle at the next scavenging, so that the pre-combustion chamber 11 can be scavenged accurately and efficiently subsequently, so as to effectively improve the scavenging quality.

[0125] Specifically, when the mass fraction of the remaining exhaust gas in the pre-combustion chamber 11 is greater than or equal to the set exhaust gas mass fraction, if (the set starting scavenging crankshaft angle for this scavenging + M°CA) is less than or equal to the minimum value of the set limit starting scavenging crankshaft angle range, and (the set scavenging crankshaft angle change for this scavenging + N°CA) is greater than or equal to the minimum value of the set limit scavenging crankshaft angle change range and less than the maximum value of the set limit scavenging crankshaft angle change range, then the set scavenging crankshaft angle change for the next scavenging is increased to increase the duration of the next scavenging, thereby enabling the pre-combustion chamber 11 to be scavenged accurately and efficiently in the subsequent period to effectively improve the scavenging quality.

[0126] Specifically, when the mass fraction of the residual exhaust gas in the pre-combustion chamber 11 is greater than or equal to the set exhaust gas mass fraction, if (the set start scavenging crankshaft angle at this scavenging + M°CA) is equal to the minimum value of the set limit start scavenging crankshaft angle range, and (the set scavenging crankshaft angle change at this scavenging + N°CA) is equal to the maximum value of the set limit scavenging crankshaft angle change range, it indicates that the pre-combustion chamber structure and / or the control valve block 2 and / or the intake branch pipe 4 and / or other structures related to the pre-combustion chamber structure are faulty and need to be repaired. Preferably, when the mass fraction of the residual exhaust gas in the pre-combustion chamber 11 is greater than or equal to the set exhaust gas mass fraction, if (the set start scavenging crankshaft angle at this scavenging + M°CA) is equal to the minimum value of the set limit start scavenging crankshaft angle range, and (the set scavenging crankshaft angle change at this scavenging + N°CA) is equal to the maximum value of the set limit scavenging crankshaft angle change range, an alarm is issued. To facilitate the detection of faults.

[0127] Thus, by adjusting the set starting scavenging crankshaft angle at the next scavenging and the set scavenging crankshaft angle change at the next scavenging, the pre-combustion chamber 11 can be scavenged accurately and efficiently subsequently, so that the scavenging quality can be effectively improved, thereby effectively reducing the risk of gas leakage from the pre-combustion chamber 11 into the main combustion chamber of the engine, so that the ignition efficiency and ignition reliability of the gas in the pre-combustion chamber 11 can be effectively improved.

[0128] Specifically, the limit start scavenging crank angle range is set to: -360°CA to -300°CA. The limit scavenging crank angle variation range is set to: 40°CA to 80°CA. Among them, the limit start scavenging crank angle range is set to the empirical range obtained from a large number of previous tests. The limit scavenging crank angle variation range is set to the empirical range obtained from a large number of previous tests.

[0129] Specifically, in this embodiment, the values ​​of M and N are both 5.

[0130] S500 , when the crankshaft angle rotates to the set combustion start crankshaft angle, the active gas passage 15 and the gas source are connected, and the gas source is synchronously controlled to deliver gas to the active gas passage 15 .

[0131] Specifically, step S500 includes:

[0132] Determine whether the current crankshaft angle is the crankshaft angle set for starting combustion during this gas intake.

[0133] If the current crankshaft angle is the crankshaft angle set for starting combustion during this fuel injection, the active fuel gas passage 15 and the fuel gas source are connected, and the fuel gas source is synchronously controlled to deliver fuel gas to the active fuel gas passage 15 .

[0134] This enables accurate control of the moment when the pre-combustion chamber 11 starts to admit fuel gas.

[0135] In this embodiment, when the scavenging is completed, the intake of combustion gas begins.

[0136] In other embodiments, it can also be set that after the scavenging is completed, when the crank angle change reaches the set crank angle change, the gas intake starts. The set crank angle change range is: 0°CA~30°CA. That is, the start time of the gas intake is delayed.

[0137] S600, disconnecting the active fuel gas passage 15 and the fuel gas source according to the set fuel gas crank angle change during the current fuel gas intake.

[0138] Specifically, step S600 includes:

[0139] Determine whether the crank angle change after the start of gas intake reaches the set crank angle change for this gas intake. If the crank angle change after the start of gas intake reaches the set crank angle change for this gas intake, disconnect the active gas channel 15 and the gas source. Specifically, at this time, control the control valve block 2 to disconnect the input end of the active gas channel 15 and the gas source. So that the moment of disconnecting the gas can be accurately controlled. In this embodiment, the set crank angle change for the first gas intake is 60°CA as an example.

[0140] It can be understood that, during the execution of steps S500 and S600 , the input end of the active scavenging channel 14 and the scavenging gas source are always kept disconnected by controlling the valve block 2 .

[0141] Specifically, while disconnecting the active gas channel 15 and the gas source, the gas volume in the current pre-combustion chamber 11 at the end of the current gas intake is monitored, and then step S700 is executed. Secondly, while disconnecting the input end of the active scavenging channel 14 and the scavenging gas source, a series of actions such as subsequent ignition are executed. It can be understood that regardless of adjusting the set crankshaft angle change amount for the next gas intake, a series of actions after the end of the current gas intake are performed normally.

[0142] Furthermore, the gas volume is obtained by monitoring the gas quality sensor; or the gas concentration is obtained by monitoring the gas concentration sensor, and then the gas volume is calculated based on the gas concentration. The specific calculation method for calculating the gas volume based on the gas concentration belongs to the prior art and will not be repeated here.

[0143] In this embodiment, since the scavenging gas and the fuel gas introduced during the fuel gas intake are the same gas, the fuel gas quality sensor can be shared to simplify the structure and reduce the cost.

[0144] S700, adjusting the set crank angle change amount for next gas injection according to the mass fraction of the gas in the pre-combustion chamber 11 at the time of the current ignition, the set crank angle change amount for the current gas injection, and the set limit crank angle change amount range. The specific calculation method for calculating the mass fraction of the gas according to the gas amount belongs to the prior art and will not be described in detail here.

[0145] Specifically, Fig.10 As shown, step S700 includes:

[0146] S710, determining whether the mass fraction of the fuel gas in the pre-combustion chamber 11 during the current ignition is within a set fuel gas mass fraction range.

[0147] If the mass fraction of the fuel gas in the pre-combustion chamber 11 during the current ignition is within the set fuel gas mass fraction range, step S720 is executed.

[0148] S720, maintaining the set crankshaft angle change amount for the next gas intake equal to the set crankshaft angle change amount for the current gas intake.

[0149] If the mass fraction of the gas in the pre-combustion chamber 11 during the current ignition is less than the minimum value of the set gas mass fraction range, step S731 and step S732 are executed.

[0150] S731, determine whether (the set combustion crank angle change amount during the current combustion + L°CA) is within the set limit combustion crank angle change amount range, where 0<L≤5.

[0151] If (the set combustion crank angle change amount during the current gas intake + L°CA) is within the set limit combustion crank angle change amount range, execute step S732.

[0152] S732, adjusting the set crank angle change amount for the next gas intake = the set crank angle change amount for the current gas intake + L°CA.

[0153] If the mass fraction of the fuel gas in the pre-combustion chamber 11 during the current ignition is greater than the maximum value of the set fuel gas mass fraction range, step S741 and step S742 are executed.

[0154] S741, determine whether (the set combustion crank angle change amount during the current combustion - L°CA) is within the set limit combustion crank angle change amount range, where 0<L≤5.

[0155] If (the set combustion crank angle change during this gas intake - L°CA) is within the set limit combustion crank angle change range, execute step S742.

[0156] S742, adjusting the set crank angle change amount for the next gas intake = the set crank angle change amount for the current gas intake - L°CA.

[0157] Specifically, if the mass fraction of the fuel gas in the pre-combustion chamber 11 during this ignition is within the set fuel gas mass fraction range, it indicates that the amount of fuel gas in the pre-combustion chamber 11 is appropriate and the set change in the combustion crankshaft angle during this fuel intake is appropriate.

[0158] Specifically, if the mass fraction of the gas in the pre-combustion chamber 11 during this ignition is less than the minimum value of the set gas mass fraction range, it indicates that the amount of gas in the pre-combustion chamber 11 is small. By increasing the set crankshaft angle change during the next gas injection, the duration of the next gas injection is increased, so that the gas can be accurately and efficiently introduced into the pre-combustion chamber 11 in the future, thereby further improving the ignition efficiency and ignition reliability of the gas in the pre-combustion chamber 11.

[0159] Specifically, if the mass fraction of the gas in the pre-combustion chamber 11 during this ignition is greater than the maximum value of the set gas mass fraction range, it indicates that the amount of gas in the pre-combustion chamber 11 is too much. By reducing the set crankshaft angle change during the next gas injection, the duration of the next gas injection can be shortened, so that the gas can be accurately and efficiently introduced into the pre-combustion chamber 11 in the future, thereby further improving the ignition efficiency and ignition reliability of the gas in the pre-combustion chamber 11.

[0160] Specifically, when the mass fraction of the gas in the pre-combustion chamber 11 during this ignition is less than the minimum value of the set gas mass fraction range, if (the set combustion crank angle change during this gas intake + L°CA) is greater than the maximum value of the set limit combustion crank angle change range, it indicates that the pre-combustion chamber structure and / or the control valve block 2 and / or the intake branch pipe 4 and / or other structures related to the pre-combustion chamber structure are faulty and need to be repaired. Preferably, when the mass fraction of the gas in the pre-combustion chamber 11 during this ignition is less than the minimum value of the set gas mass fraction range, if (the set combustion crank angle change during this gas intake + L°CA) is greater than the maximum value of the set limit combustion crank angle change range, an alarm is issued. This is to facilitate the detection of faults.

[0161] Specifically, when the mass fraction of the gas in the pre-combustion chamber 11 during this ignition is greater than the maximum value of the set gas mass fraction range, if (the set combustion crank angle change during this gas intake - L ° CA) is less than the minimum value of the set limit combustion crank angle change range, it indicates that the pre-combustion chamber structure and / or the control valve block 2 and / or the intake branch pipe 4 and / or other structures related to the pre-combustion chamber structure are faulty and need to be repaired. Preferably, when the mass fraction of the gas in the pre-combustion chamber 11 during this ignition is greater than the maximum value of the set gas mass fraction range, if (the set combustion crank angle change during this gas intake - L ° CA) is less than the minimum value of the set limit combustion crank angle change range, an alarm is issued. This is to facilitate the detection of faults.

[0162] Therefore, by adjusting the set crankshaft angle change when the gas is fed next time, the gas can be accurately and efficiently introduced into the pre-combustion chamber 11 subsequently, thereby further improving the ignition efficiency and ignition reliability of the gas in the pre-combustion chamber 11.

[0163] Specifically, the gas quality fraction range is set to 0.049 to 0.053, wherein the gas quality fraction range is set to an empirical range obtained from a large number of previous tests.

[0164] Specifically, the range of the limit crank angle change is set to 40°CA to 100°CA. In this embodiment, the limit crank angle change when the first fuel gas is fed is 60°CA. The limit scavenging crank angle range is set to the empirical range obtained from a large number of previous tests. The limit scavenging crank angle range is set to the empirical range obtained from a large number of previous tests.

[0165] Specifically, in this embodiment, the value of L is 5 as an example.

[0166] Specifically, in this embodiment, the injection pressure of the scavenging gas and the injection pressure of the fuel gas introduced into the pre-combustion chamber 11 are both 6 bar to 8 bar.

[0167] Specifically, in this embodiment, the set starting scavenging crankshaft angle during the first scavenging is -320°CA; the set scavenging crankshaft angle change during the first scavenging is 60°CA; when the scavenging is completed, the gas intake begins; the set combustion crankshaft angle change during the first gas intake is 60°CA.

[0168] The optimal control strategy finally obtained by the above engine control method is:

[0169] During scavenging, the crankshaft angle for starting scavenging is set to -345°CA; the change in the crankshaft angle for scavenging is set to 65°CA. When introducing fuel gas into the pre-combustion chamber 11, the crankshaft angle for starting combustion is set to -280°CA (i.e., when scavenging is completed, fuel gas is introduced); the change in the crankshaft angle for combustion is set to 50°CA. Compared with the prior art, the mass fraction of the remaining exhaust gas in the pre-combustion chamber 11 is reduced by 0.005. In order to satisfy the formation of equivalent combustion in the pre-combustion chamber 11, it is necessary to control the equivalent ratio in the pre-combustion chamber 11 to be near 1 or the excess air coefficient to be near 1 at the ignition moment, by Fig.11 and Fig.12 It can be seen that the mass fraction of the fuel gas in the pre-combustion chamber 11 at this time is 0.051, and the crankshaft angle corresponding to the ignition timing is -15°CA.

[0170] Therefore, by adopting this engine control method, the scavenging quality of the pre-combustion chamber 11 can be effectively improved, and the ignition efficiency and ignition reliability of the fuel gas in the pre-combustion chamber 11 can be effectively improved.

[0171] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An engine control method, wherein the engine comprises a pre-combustion chamber structure, wherein the pre-combustion chamber structure comprises a pre-combustion chamber body (1), wherein the pre-combustion chamber body (1) is provided with a pre-combustion chamber (11); characterized in that: The engine control method comprises: Determining whether to adjust the set scavenging crank angle for starting scavenging at the next scavenging and the set scavenging crank angle change amount at the next scavenging according to the residual exhaust gas amount in the pre-combustion chamber (11) at this time; The set start scavenging crank angle for the next scavenging and the set scavenging crank angle change for the next scavenging are adjusted based on the set start scavenging crank angle for the current scavenging, the set scavenging crank angle change for the current scavenging, the set limit start scavenging crank angle range and the set limit scavenging crank angle change range.

2. The engine control method according to claim 1, characterized in that: The step of determining whether to adjust the set scavenging crank angle for starting scavenging at the next scavenging and the set scavenging crank angle change amount at the next scavenging according to the residual exhaust gas amount in the current pre-combustion chamber (11) comprises: Determining whether the mass fraction of the remaining exhaust gas in the pre-combustion chamber (11) is less than a set exhaust gas mass fraction; If the mass fraction of the residual exhaust gas in the pre-combustion chamber (11) is less than the set exhaust gas mass fraction, the set scavenging crank angle at the next start of scavenging is kept equal to the set scavenging crank angle at the current start of scavenging, and the change amount of the set scavenging crank angle at the next scavenging is kept equal to the change amount of the set scavenging crank angle at the current scavenging; If the mass fraction of the remaining exhaust gas in the pre-combustion chamber (11) is greater than or equal to the set exhaust gas mass fraction, the set start scavenging crank angle at the next scavenging and the set scavenging crank angle change at the next scavenging are adjusted.

3. The engine control method according to claim 1, characterized in that: The step of adjusting the set start scavenging crank angle for next scavenging and the set scavenging crank angle change amount for next scavenging according to the set start scavenging crank angle for this scavenging, the set scavenging crank angle change amount for this scavenging, the set limit start scavenging crank angle range, and the set limit scavenging crank angle change amount range comprises: Determine whether (the set start scavenging crank angle at this scavenging time + M°CA) is less than or equal to the minimum value of the set limit start scavenging crank angle range; wherein 0>M≥-5; If (the set starting scavenging crankshaft angle for this scavenging + M°CA) is greater than the minimum value of the set limit starting scavenging crankshaft angle range and is less than or equal to the maximum value of the set limit starting scavenging crankshaft angle range, then the set starting scavenging crankshaft angle for the next scavenging is adjusted to = the set starting scavenging crankshaft angle for this scavenging + M°CA.

4. The engine control method according to claim 3, characterized in that: If (the set scavenging crank angle at the start of this scavenging + M°CA) is less than or equal to the minimum value of the set limit scavenging crank angle range, then determine whether (the set scavenging crank angle change at the start of this scavenging + N°CA) is greater than or equal to the maximum value of the set limit scavenging crank angle change range; wherein 0<N≤5; If (the set scavenging crank angle change during this scavenging + N°CA) is greater than or equal to the minimum value of the set limit scavenging crank angle change range and is less than the maximum value of the set limit scavenging crank angle change range, then the set scavenging crank angle change during the next scavenging is adjusted to = the set scavenging crank angle change during this scavenging + N°CA.

5. The engine control method according to any one of claims 1 to 4, characterized in that: The crankshaft angle range for starting scavenging at the set limit is: -360°CA to -300°CA; The range of the set limit scavenging crank angle variation is: 40°CA~80°CA.

6. The engine control method according to any one of claims 1 to 4, characterized in that: The pre-combustion chamber body (1) is provided with an active gas channel (15) communicating with the pre-combustion chamber (11), and an input end of the active gas channel (15) can be selectively communicated with a gas source; the engine control method further comprises: After the scavenging is completed, when the crankshaft angle rotates to a set crankshaft angle for starting combustion, the active fuel gas passage (15) and the fuel gas source are connected, and the fuel gas source is synchronously controlled to deliver fuel gas to the active fuel gas passage (15); disconnecting the active fuel gas passage (15) and the fuel gas source according to the set fuel gas crank angle change during the current fuel gas intake; The set combustion crank angle change amount for the next combustion gas injection is adjusted according to the mass fraction of the combustion gas in the pre-combustion chamber (11) during the current ignition, the set combustion crank angle change amount during the current combustion gas injection, and the set limit combustion crank angle change amount range.

7. The engine control method according to claim 6, characterized in that: The step of adjusting the set combustion crank angle change amount for the next combustion gas injection according to the mass fraction of the combustion gas in the pre-combustion chamber (11) during the current ignition, the set combustion crank angle change amount during the current combustion gas injection, and the set limit combustion crank angle change amount range comprises: Determining whether the mass fraction of the fuel gas in the pre-combustion chamber (11) during the current ignition is within a set fuel gas mass fraction range; If the mass fraction of the fuel gas in the pre-combustion chamber (11) during the current ignition is within the set fuel gas mass fraction range, the set fuel crank angle change amount during the next fuel injection is kept equal to the set fuel crank angle change amount during the current fuel injection; If the mass fraction of the fuel gas in the pre-combustion chamber (11) during the current ignition is less than the minimum value of the set fuel gas mass fraction range, it is determined whether (the set fuel gas crank angle change amount during the current fuel gas injection + L°CA) is within the set limit fuel gas crank angle change amount range; wherein 0<L≤5; If (the set crank angle change amount for this gas injection + L°CA) is within the set limit crank angle change amount range, then the set crank angle change amount for the next gas injection is adjusted to be the set crank angle change amount for this gas injection + L°CA; If the mass fraction of the fuel gas in the pre-combustion chamber (11) during the current ignition is greater than the maximum value of the set fuel gas mass fraction range, then it is determined whether (the set fuel intake crank angle change during the current fuel intake - L°CA) is within the set limit fuel intake crank angle change range; If (the set crank angle change during this gas intake - L°CA) is within the set limit crank angle change range, then the set crank angle change during the next gas intake is adjusted to = the set crank angle change during this gas intake - L°CA.

8. The engine control method according to claim 7, characterized in that: The range of the set limit combustion crankshaft angle change is: 40°CA~100°CA.

9. The engine control method according to any one of claims 1 to 4, characterized in that: The pre-combustion chamber body (1) is further provided with an active scavenging passage (14) in communication with the pre-combustion chamber (11), and an input end of the active scavenging passage (14) can be selectively connected to a scavenging air source; Before determining whether to adjust the set scavenging crank angle for starting scavenging at the next scavenging and the set scavenging crank angle change amount at the next scavenging according to the residual exhaust gas amount in the current pre-combustion chamber (11), the following steps are also included: Connecting the input end of the active scavenging passage (14) and the scavenging gas source according to the scavenging crankshaft angle set at the time of the current scavenging, and synchronously controlling the scavenging gas source to deliver gas to the active scavenging passage (14) for scavenging; The input end of the active scavenging passage (14) and the scavenging gas source are disconnected according to the set scavenging crankshaft angle change during the current scavenging to end the scavenging.

10. An engine, comprising a pre-combustion chamber structure, the pre-combustion chamber structure comprising a pre-combustion chamber body (1), the pre-combustion chamber body (1) being provided with a pre-combustion chamber (11); characterized in that: Used to execute the engine control method described in any one of claims 1-9.

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