Method and device for optimizing performance of hydrogen internal combustion engine
By establishing a performance simulation model of hydrogen internal combustion engine, fitting the parameters of hydrogen injection and ignition time, building an optimization function, and solving the best time, the problem of degradation of combustion performance of hydrogen internal combustion engine is solved, and stable operation and performance improvement is achieved.
Patent Information
- Application Number
- CN202510562005.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-30
- Publication Date
- 2025-08-08
AI Technical Summary
The prior art fails to effectively consider the coupling relationship between the hydrogen injection time and the ignition time in the hydrogen internal combustion engine, resulting in a degradation of combustion performance and abnormal combustion, affecting the normal operation of the hydrogen internal combustion engine.
Establish a performance simulation model of hydrogen internal combustion engine, fit the input parameters of multiple sets of hydrogen injection time and ignition time, build power, thermal efficiency and emission functions, and use the comprehensive optimization function to solve the optimal hydrogen injection and ignition time to achieve optimized control of hydrogen internal combustion engine.
The performance of hydrogen internal combustion engine is improved, ensuring stable operation under different working conditions, and avoiding abnormal combustion such as backfire and premature combustion.
Smart Images
Figure CN120449474A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of internal combustion engine optimization, and in particular to a method and device for optimizing a hydrogen internal combustion engine. Background Art
[0002] Under the premise of the goal of low-carbon energy transition, the search and development of new alternative fuels for automobiles is inevitable for the sustainable development of the internal combustion engine industry. Hydrogen, due to its many characteristics such as clean and renewable, zero carbon emissions, and diverse production methods, is considered an alternative fuel with great development prospects.
[0003] However, improper adjustment of operating and structural parameters when using hydrogen fuel in port-injected internal combustion engines can lead to reduced combustion and emissions performance, and even cause abnormal combustion phenomena such as backfire and pre-ignition, affecting normal operation. Therefore, continuous optimization of hydrogen engine parameters is necessary to achieve optimal performance under varying operating conditions. Given the physicochemical properties of hydrogen, adjusting and optimizing the fuel injection and ignition systems can most effectively control the mixing of hydrogen and air and the combustion process.
[0004] Previous studies on optimizing the injection timing or ignition timing of hydrogen internal combustion engines were mostly based on single-variable control methods, with little consideration of the coupling relationship between parameters, resulting in a lack of reliability in the research results. Summary of the Invention
[0005] In view of this, the present application provides a method for optimizing the performance of a hydrogen internal combustion engine, which can improve the performance of a hydrogen internal combustion engine. The method comprises:
[0006] In one aspect, the present application provides a method for optimizing the performance of a hydrogen internal combustion engine, the method comprising:
[0007] Establish a hydrogen internal combustion engine performance simulation model.
[0008] Multiple sets of mid-screen parameters are input into the hydrogen internal combustion engine performance simulation model as input quantities to obtain multiple mid-screen powers, multiple mid-screen thermal efficiencies and multiple mid-screen emission mass fractions as outputs. The multiple sets of mid-screen parameters include multiple mid-screen hydrogen injection moments and multiple mid-screen ignition moments.
[0009] Multiple mid-screen hydrogen injection times, multiple mid-screen ignition times, multiple mid-screen powers, multiple mid-screen thermal efficiencies and multiple mid-screen emission mass fractions were fitted to obtain a power function with ignition time and hydrogen injection time as independent variables and power as dependent variable, a thermal efficiency function with ignition time and hydrogen injection time as independent variables and thermal efficiency as dependent variable, and an emission function with ignition time and hydrogen injection time as independent variables and emission mass fraction as dependent variable.
[0010] According to the power function, thermal efficiency function and emission function as well as preset weights, a comprehensive optimization function is obtained.
[0011] The comprehensive optimization function is solved to obtain the optimal ignition time and the optimal hydrogen injection time.
[0012] The hydrogen internal combustion engine is controlled according to the optimal ignition timing and the optimal hydrogen injection timing.
[0013] Optionally, multiple sets of mid-screen parameters are input as inputs into a hydrogen internal combustion engine performance simulation model to obtain multiple mid-screen powers, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions as outputs, the multiple sets of mid-screen parameters including multiple mid-screen hydrogen injection moments and multiple mid-screen ignition moments. The method further comprises:
[0014] Multiple sets of preset parameters are input as input into the hydrogen internal combustion engine performance simulation model to obtain multiple output preliminary screening powers, multiple preliminary screening thermal efficiencies and multiple preliminary screening emission mass fractions. The multiple sets of preset parameters include multiple preset hydrogen injection times and multiple preset ignition times.
[0015] According to the maximum values of multiple primary screening powers, multiple maximum values of primary screening thermal efficiencies and multiple maximum values of primary screening emission mass fractions, the primary screening hydrogen injection time is determined from multiple preset hydrogen injection times, and the primary screening ignition time is determined from multiple preset ignition times.
[0016] The optimal range for hydrogen injection timing is determined near the primary screening hydrogen injection timing, and the optimal range for ignition timing is determined near the primary screening ignition timing.
[0017] A plurality of mid-screen hydrogen injection timings are determined in the hydrogen injection timing optimization interval, and a plurality of mid-screen ignition timings are determined in the ignition timing optimization interval.
[0018] Multiple preset hydrogen injection moments included in multiple sets of preset parameters are replaced by multiple mid-screen hydrogen injection moments, and multiple preset ignition moments included in multiple sets of preset parameters are replaced by multiple mid-screen ignition moments to obtain multiple sets of replaced mid-screen parameters.
[0019] Optionally, the multiple sets of preset parameters include 9 sets of preset parameters corresponding to 9 operating conditions of the hydrogen internal combustion engine, and the 9 operating conditions include:
[0020] The hydrogen internal combustion engine is at low speed and low load, the hydrogen internal combustion engine is at low speed and medium load, the hydrogen internal combustion engine is at low speed and high load, the hydrogen internal combustion engine is at medium speed and low load, the hydrogen internal combustion engine is at medium speed and medium load, the hydrogen internal combustion engine is at medium speed and high load, the hydrogen internal combustion engine is at high speed and low load, the hydrogen internal combustion engine is at high speed and medium load, and the hydrogen internal combustion engine is at high speed and high load.
[0021] Each operating condition corresponds to 4 preset hydrogen injection times and 4 preset ignition times, and the 4 preset hydrogen injection times corresponding to different operating conditions are exactly the same.
[0022] Optionally, two preset hydrogen injection timings and four preset ignition timings correspond to the operating condition of the hydrogen internal combustion engine being in a high speed and high load condition.
[0023] Optionally, the units of the ignition timing and the hydrogen injection timing are angles, wherein determining the optimal interval for the hydrogen injection timing near the initial screening hydrogen injection timing includes:
[0024] The angle obtained by subtracting 10 degrees from the initial screening hydrogen injection time is used as the lower limit of the optimal range for hydrogen injection time, and the angle obtained by adding 10 degrees to the initial screening hydrogen injection time is used as the upper limit of the optimal range for hydrogen injection time.
[0025] Determining the optimal interval for ignition timing near the initial screening ignition timing includes:
[0026] The angle obtained by subtracting the preset angle from the initial screening ignition time is used as the lower limit of the ignition time optimization interval, and the angle obtained by adding the preset angle to the initial screening ignition time is used as the upper limit of the ignition time optimization interval.
[0027] Optionally, determining a plurality of mid-screen hydrogen injection times in the hydrogen injection timing optimization interval includes:
[0028] In the hydrogen injection timing optimization interval, 7 middle screen hydrogen injection timings with equal intervals are evenly determined.
[0029] Determining multiple mid-screen ignition times in the ignition time optimization interval includes:
[0030] In the ignition timing optimization interval, seven equally spaced mid-screen ignition times are uniformly determined.
[0031] Optionally, multiple mid-screen hydrogen injection times, multiple mid-screen ignition times, multiple mid-screen powers, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions are fitted to obtain a power function with the ignition time and the hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and the hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and the hydrogen injection time as independent variables and the emission mass fraction as the dependent variable, including:
[0032] The power of multiple mid-screens, thermal efficiencies of multiple mid-screens and emission mass fractions of multiple mid-screens are dimensionlessly processed.
[0033] Regression fitting is performed on multiple mid-screen hydrogen injection moments, multiple mid-screen ignition moments, multiple mid-screen powers after dimensionless processing, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions to obtain the power initial regression model, thermal efficiency initial regression model, and emission initial regression model.
[0034] The power initial regression model, thermal efficiency initial regression model and emission initial regression model were respectively tested for significance, and the insignificant factors in the power initial regression model, thermal efficiency initial regression model and emission initial regression model were eliminated to obtain the optimal power regression model, thermal efficiency optimal regression model and emission optimal regression model. Among them, the power optimal regression model corresponds to the power function with ignition time and hydrogen injection time as independent variables and power as the dependent variable, the thermal efficiency optimal regression model corresponds to the thermal efficiency function with ignition time and hydrogen injection time as independent variables and thermal efficiency as the dependent variable, and the emission optimal regression model corresponds to the emission function with ignition time and hydrogen injection time as independent variables and emission mass fraction as the dependent variable.
[0035] Optionally, the weights include three weight groups corresponding to the low-load operating conditions, medium-load operating conditions and high-load operating conditions of the hydrogen internal combustion engine, each weight group includes power weight, thermal efficiency weight and emission weight, and the power weight, thermal efficiency weight and emission weight in different weight groups are not exactly the same.
[0036] Optionally, the comprehensive optimization function includes a first comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and low load, a second comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and medium load, a third comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and high load, a fourth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and low load, a fifth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and medium load, a sixth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and high load, a seventh comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and low load, an eighth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and medium load, and a ninth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and high load.
[0037] On the other hand, the present application provides a hydrogen internal combustion engine performance optimization device, including a processor, a memory, and a computer program stored in the memory and runnable on the processor, characterized in that when the computer program is executed by the processor, the hydrogen internal combustion engine performance optimization method provided in the above aspect is implemented.
[0038] By adopting the hydrogen internal combustion engine performance optimization method provided in the present application, multiple parameters are input into the hydrogen internal combustion engine performance simulation model to obtain multiple output powers, multiple efficiencies and multiple emission mass fractions. The input parameters include multiple hydrogen injection times and multiple ignition times. The input and output quantities are fitted to obtain a power function with the ignition time and hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and hydrogen injection time as independent variables and the emission mass fraction as the dependent variable. Based on these functions and preset weights, a comprehensive optimization function is obtained. The comprehensive optimization function reflects the influence of the ignition time and hydrogen injection time on the comprehensive performance of the hydrogen internal combustion engine under specific working conditions. The optimal ignition time and the optimal hydrogen injection time can be obtained by solving the comprehensive optimization function. The performance of the hydrogen internal combustion engine can be improved by controlling the hydrogen internal combustion engine according to the optimal ignition time and the optimal hydrogen injection time. BRIEF DESCRIPTION OF THE DRAWINGS
[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application, 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.
[0040] Figure 1 A flow chart of a method for optimizing the performance of a hydrogen internal combustion engine provided in an embodiment of the present application;
[0041] Figure 2 Another flow chart of the method for optimizing the performance of a hydrogen internal combustion engine provided in an embodiment of the present application;
[0042] Figure 3 A histogram of simulation outputs of the hydrogen internal combustion engine performance optimization method provided in an embodiment of the present application;
[0043] Figure 4 This is a structural diagram of the hydrogen internal combustion engine performance optimization device provided in an embodiment of the present application. DETAILED DESCRIPTION
[0044] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.
[0045] The present application provides a method for optimizing the performance of a hydrogen internal combustion engine. Figure 1As shown, the method includes steps S101, S102, S103, S104, S105 and S106, wherein:
[0046] In step S101 , a hydrogen internal combustion engine performance simulation model is established.
[0047] In step S102, multiple groups of mid-screen parameters are input as input quantities into the hydrogen internal combustion engine performance simulation model to obtain multiple mid-screen powers, multiple mid-screen thermal efficiencies and multiple mid-screen emission mass fractions as outputs. The multiple groups of mid-screen parameters include multiple mid-screen hydrogen injection moments and multiple mid-screen ignition moments.
[0048] In step S103, multiple mid-screen hydrogen injection times, multiple mid-screen ignition times, multiple mid-screen powers, multiple mid-screen thermal efficiencies and multiple mid-screen emission mass fractions are fitted to obtain a power function with the ignition time and the hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and the hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and the hydrogen injection time as independent variables and the emission mass fraction as the dependent variable.
[0049] In step S104, a comprehensive optimization function is obtained according to the power function, the thermal efficiency function, the emission function and the preset weights.
[0050] In step S105 , the comprehensive optimization function is solved to obtain the optimal ignition timing and the optimal hydrogen injection timing.
[0051] In step S106, the hydrogen internal combustion engine is controlled according to the optimal ignition timing and the optimal hydrogen injection timing.
[0052] In some optional embodiments, multiple sets of mid-screen parameters are input as inputs into a hydrogen internal combustion engine performance simulation model to obtain multiple mid-screen powers, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions as outputs, the multiple sets of mid-screen parameters including multiple mid-screen hydrogen injection moments and multiple mid-screen ignition moments. The method further includes:
[0053] Multiple sets of preset parameters are input as input into the hydrogen internal combustion engine performance simulation model to obtain multiple output preliminary screening powers, multiple preliminary screening thermal efficiencies and multiple preliminary screening emission mass fractions. The multiple sets of preset parameters include multiple preset hydrogen injection times and multiple preset ignition times.
[0054] According to the maximum values of multiple primary screening powers, multiple maximum values of primary screening thermal efficiencies and multiple maximum values of primary screening emission mass fractions, the primary screening hydrogen injection time is determined from multiple preset hydrogen injection times, and the primary screening ignition time is determined from multiple preset ignition times.
[0055] The optimal range for hydrogen injection timing is determined near the primary screening hydrogen injection timing, and the optimal range for ignition timing is determined near the primary screening ignition timing.
[0056] A plurality of mid-screen hydrogen injection timings are determined in the hydrogen injection timing optimization interval, and a plurality of mid-screen ignition timings are determined in the ignition timing optimization interval.
[0057] Multiple preset hydrogen injection moments included in multiple sets of preset parameters are replaced by multiple mid-screen hydrogen injection moments, and multiple preset ignition moments included in multiple sets of preset parameters are replaced by multiple mid-screen ignition moments to obtain multiple sets of replaced mid-screen parameters.
[0058] In some optional embodiments, the multiple sets of preset parameters include 9 sets of preset parameters corresponding to 9 operating conditions of the hydrogen internal combustion engine, and the 9 operating conditions include:
[0059] The hydrogen internal combustion engine is at low speed and low load, the hydrogen internal combustion engine is at low speed and medium load, the hydrogen internal combustion engine is at low speed and high load, the hydrogen internal combustion engine is at medium speed and low load, the hydrogen internal combustion engine is at medium speed and medium load, the hydrogen internal combustion engine is at medium speed and high load, the hydrogen internal combustion engine is at high speed and low load, the hydrogen internal combustion engine is at high speed and medium load, and the hydrogen internal combustion engine is at high speed and high load.
[0060] Each operating condition corresponds to 4 preset hydrogen injection times and 4 preset ignition times, and the 4 preset hydrogen injection times corresponding to different operating conditions are exactly the same.
[0061] In some optional embodiments, there are 2 preset hydrogen injection times and 4 preset ignition times corresponding to the operating condition of the hydrogen internal combustion engine at high speed and high load.
[0062] In some optional embodiments, the units of the ignition timing and the hydrogen injection timing are angles, wherein determining the optimal interval for the hydrogen injection timing near the initial screening hydrogen injection timing includes:
[0063] The angle obtained by subtracting 10 degrees from the initial screening hydrogen injection time is used as the lower limit of the optimal range for hydrogen injection time, and the angle obtained by adding 10 degrees to the initial screening hydrogen injection time is used as the upper limit of the optimal range for hydrogen injection time.
[0064] Determining the optimal interval for ignition timing near the initial screening ignition timing includes:
[0065] The angle obtained by subtracting the preset angle from the initial screening ignition time is used as the lower limit of the ignition time optimization interval, and the angle obtained by adding the preset angle to the initial screening ignition time is used as the upper limit of the ignition time optimization interval.
[0066] In some optional embodiments, determining a plurality of mid-screen hydrogen injection times in the hydrogen injection timing optimization interval includes:
[0067] In the hydrogen injection timing optimization interval, 7 middle screen hydrogen injection timings with equal intervals are evenly determined.
[0068] Determining multiple mid-screen ignition times in the ignition time optimization interval includes:
[0069] In the ignition timing optimization interval, seven equally spaced mid-screen ignition times are uniformly determined.
[0070] In some optional embodiments, multiple mid-screen hydrogen injection times, multiple mid-screen ignition times, multiple mid-screen powers, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions are fitted to obtain a power function with the ignition time and the hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and the hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and the hydrogen injection time as independent variables and the emission mass fraction as the dependent variable, including:
[0071] The power of multiple mid-screens, thermal efficiencies of multiple mid-screens and emission mass fractions of multiple mid-screens are dimensionlessly processed.
[0072] Regression fitting is performed on multiple mid-screen hydrogen injection moments, multiple mid-screen ignition moments, multiple mid-screen powers after dimensionless processing, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions to obtain the power initial regression model, thermal efficiency initial regression model, and emission initial regression model.
[0073] The power initial regression model, thermal efficiency initial regression model and emission initial regression model were respectively tested for significance, and the insignificant factors in the power initial regression model, thermal efficiency initial regression model and emission initial regression model were eliminated to obtain the optimal power regression model, thermal efficiency optimal regression model and emission optimal regression model. Among them, the power optimal regression model corresponds to the power function with ignition time and hydrogen injection time as independent variables and power as the dependent variable, the thermal efficiency optimal regression model corresponds to the thermal efficiency function with ignition time and hydrogen injection time as independent variables and thermal efficiency as the dependent variable, and the emission optimal regression model corresponds to the emission function with ignition time and hydrogen injection time as independent variables and emission mass fraction as the dependent variable.
[0074] In some optional embodiments, the weights include three weight groups corresponding to the low-load operating conditions, medium-load operating conditions and high-load operating conditions of the hydrogen internal combustion engine. Each weight group includes power weight, thermal efficiency weight and emission weight. The power weight, thermal efficiency weight and emission weight in different weight groups are not exactly the same.
[0075] In some optional embodiments, the comprehensive optimization function includes a first comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and low load, a second comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and medium load, a third comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and high load, a fourth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and low load, a fifth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and medium load, a sixth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and high load, a seventh comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and low load, an eighth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and medium load, and a ninth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and high load.
[0076] By adopting the hydrogen internal combustion engine performance optimization method provided in the present application, multiple parameters are input into the hydrogen internal combustion engine performance simulation model to obtain multiple output powers, multiple efficiencies and multiple emission mass fractions. The input parameters include multiple hydrogen injection times and multiple ignition times. The input and output quantities are fitted to obtain a power function with the ignition time and hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and hydrogen injection time as independent variables and the emission mass fraction as the dependent variable. Based on these functions and preset weights, a comprehensive optimization function is obtained. The comprehensive optimization function reflects the influence of the ignition time and hydrogen injection time on the comprehensive performance of the hydrogen internal combustion engine under specific working conditions. The optimal ignition time and the optimal hydrogen injection time can be obtained by solving the comprehensive optimization function. The performance of the hydrogen internal combustion engine can be improved by controlling the hydrogen internal combustion engine according to the optimal ignition time and the optimal hydrogen injection time.
[0077] The present application also provides a method for optimizing the performance of a hydrogen internal combustion engine. Figure 2 As shown, the method includes steps S201, S202, S203, S204, S205, S206, S207, S208, S209, S210 and S211, wherein:
[0078] In step S201 , a hydrogen internal combustion engine performance simulation model is established.
[0079] It is understandable that the performance simulation model of the hydrogen internal combustion engine can be established in FIRE, a three-dimensional CFD simulation calculation software developed and designed by AVL of Austria, which is specialized in simulating complex fluid change processes such as the intake fuel injection characteristics, the organization of the mixture and the combustion in the cylinder of the internal combustion engine.
[0080] To verify the reliability of the simulation, several specific operating conditions were selected and compared on a hydrogen internal combustion engine test bench. The test system primarily consists of a hydrogen supply system, a hydrogen safety system, a hydrogen internal combustion engine test bench system, an electronic control system, and a test system. Parameters such as cylinder pressure and transient heat release rate were analyzed using AVL INDICOM, the combustion analyzer's supporting software. After simulation and experimental analysis, the results were found to be within the allowable error range. Therefore, simulations based on the hydrogen internal combustion engine performance simulation model can effectively represent the actual engine operation process.
[0081] In step S202, multiple sets of preset parameters are input as input quantities into the hydrogen internal combustion engine performance simulation model to obtain multiple output preliminary screening powers, multiple preliminary screening thermal efficiencies and multiple preliminary screening emission mass fractions. The multiple sets of preset parameters include multiple preset hydrogen injection times and multiple preset ignition times.
[0082] It is understandable that in the process of determining the most accurate optimal hydrogen injection timing and the optimal ignition timing, initially only multiple preset hydrogen injection timings and multiple preset ignition timings under various working conditions can be given as guesses. By using the full test plan and with the help of the hydrogen internal combustion engine performance simulation model, the relatively optimal hydrogen injection timing and the relatively optimal optimal ignition timing among these preset hydrogen injection timings and preset ignition timings are obtained. However, the multiple preset hydrogen injection timings and the multiple preset ignition timings are rounded, so the relatively optimal hydrogen injection timing and the relatively optimal optimal ignition timing are also rounded. In other words, the relatively optimal hydrogen injection timing and the relatively optimal optimal ignition timing are not necessarily the final optimal hydrogen injection timing and the optimal ignition timing. Therefore, it is necessary to further use the uniform test plan and fitting in the future to obtain the most accurate optimal hydrogen injection timing and the optimal ignition timing.
[0083] In some optional embodiments, the multiple groups of preset parameters include 9 groups of preset parameters corresponding one-to-one to the 9 operating conditions of the hydrogen internal combustion engine.
[0084] Table 1
[0085]
[0086] It can be understood that, as shown in Table 1, the nine working conditions include:
[0087] The hydrogen internal combustion engine is at low speed (1000rpm) and low load (10%), the hydrogen internal combustion engine is at low speed (1000rpm) and medium load (50%), the hydrogen internal combustion engine is at low speed (1000rpm) and high load (100%), the hydrogen internal combustion engine is at medium speed (3000rpm) and low load (10%), the hydrogen internal combustion engine is at medium speed (3000rpm) and medium load (50%), the hydrogen internal combustion engine is at medium speed (3000rpm) and high load (100%), the hydrogen internal combustion engine is at high speed (6000rpm) and low load (10%), the hydrogen internal combustion engine is at high speed (6000rpm) and medium load (50%), and the hydrogen internal combustion engine is at high speed (6000rpm) and high load (100%).
[0088] The four preset hydrogen injection times corresponding to different working conditions are exactly the same, namely 394°, 404°, 414° and 424°. It can be understood that the time is represented by the crankshaft angle, and the unit is degree (°).
[0089] In some optional embodiments, when the hydrogen internal combustion engine is in a high-speed and high-load operating condition, if the hydrogen injection timing is too late, it may lead to poor mixing quality of the mixture after hydrogen injection, and make the engine combustion and power state extremely poor. Therefore, when the hydrogen internal combustion engine is in a high-speed and high-load operating condition, it can also correspond to only two earlier preset hydrogen injection times, namely 394° and 404°.
[0090] As shown in Table 1:
[0091] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at low speed (1000 rpm) and low load (10%) are 704°, 706°, 708° and 710°.
[0092] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at low speed (1000 rpm) and medium load (50%) are 706°, 708°, 710° and 712°.
[0093] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at low speed (1000 rpm) and high load (100%) are 708°, 710°, 712° and 714°.
[0094] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at medium speed (3000 rpm) and low load (10%) are 694°, 698°, 702° and 706°.
[0095] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at medium speed (3000 rpm) and medium load (50%) are 702°, 706°, 710° and 714°.
[0096] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at medium speed (3000 rpm) and high load (100%) are 702°, 706°, 710° and 714°.
[0097] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at high speed (6000 rpm) and low load (10%) are 684°, 690°, 696° and 702°.
[0098] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at high speed (6000 rpm) and medium load (50%) are 690°, 696°, 702° and 708°.
[0099] The four preset ignition timings corresponding to the operating conditions of the hydrogen internal combustion engine at high speed (6000 rpm) and high load (100%) are 694°, 700°, 706° and 712°.
[0100] It can be understood that the nine operating conditions, four preset hydrogen injection times, and four preset ignition times, combined together, constitute 9*4*4, or 144 sets of preset parameters. The full test plan requires simulation and calculation of the hydrogen internal combustion engine's performance indicators under 144 sets of preset parameters to reveal the influence of hydrogen injection and ignition timing on the power, thermal efficiency, and emissions of the hydrogen internal combustion engine. Specifically, the 144 sets of preset parameters are input into the pre-established hydrogen internal combustion engine performance simulation model in the simulation calculation software FIRE, and the output is the initial screening power, initial screening thermal efficiency, and initial screening emission mass fraction.
[0101] In step S203, the primary screening hydrogen injection time is determined from multiple preset hydrogen injection times, and the primary screening ignition time is determined from multiple preset ignition times based on multiple maximum values of primary screening powers, multiple maximum values of primary screening thermal efficiencies, and multiple maximum values of primary screening emission mass fractions.
[0102] It can be understood that, for example, after inputting 144 sets of preset parameters as input into the pre-established hydrogen internal combustion engine performance simulation model in the simulation calculation software FIRE, the output primary screening power, primary screening thermal efficiency and primary screening emission mass fraction are obtained, according to the maximum values of multiple primary screening powers, multiple primary screening thermal efficiencies and multiple primary screening emission mass fractions, such as the simulation output column Figure 3 (a)-(i) are shown, where the horizontal axis is the hydrogen injection time, and different filling textures correspond to different ignition times (as shown in the figure). According to the simulation output column Figure 3 (a)-(i) can determine:
[0103] As for the hydrogen injection timing, when the rotation speed is 1000rpm, 3000rpm and 6000rpm, the initial screening hydrogen injection timing is 394°, 414° and 424° respectively, and the hydrogen injection timing has little to do with the load.
[0104] Regarding ignition timing, at 1000 rpm, low, medium, and high load, the initial ignition timings were 708°, 710°, and 712°, respectively. At 3000 rpm, low, medium, and high load, the initial ignition timings were 698°, 706°, and 706°, respectively. At 6000 rpm, low, medium, and high load, the initial ignition timings were 690°, 702°, and 706°, respectively.
[0105] In step S204, an optimal hydrogen injection timing interval is determined near the primary screening hydrogen injection timing, and an optimal ignition timing interval is determined near the primary screening ignition timing.
[0106] In order to find the optimal values of hydrogen injection timing and ignition timing of hydrogen fuel engines under different speed and load conditions, a uniform test scheme with good uniformity, representativeness and robustness is used. The optimal values of the test factors can be obtained through data post-processing analysis with a smaller number of tests, which better avoids the subjectivity and large errors in conventional value optimization methods.
[0107] The initial screening hydrogen injection timing and the initial screening ignition timing determined by the full test plan (steps S202+S203) are expanded to the left and right to form the optimal hydrogen injection timing interval and the optimal ignition timing interval.
[0108] In some optional embodiments, the units of the ignition timing and the hydrogen injection timing are angles, wherein determining the optimal interval for the hydrogen injection timing near the initial screening hydrogen injection timing includes:
[0109] The angle obtained by subtracting 10 degrees from the initial screening hydrogen injection time is used as the lower limit of the optimal range for hydrogen injection time, and the angle obtained by adding 10 degrees to the initial screening hydrogen injection time is used as the upper limit of the optimal range for hydrogen injection time.
[0110] Determining the optimal interval for ignition timing near the initial screening ignition timing includes:
[0111] The angle obtained by subtracting the preset angle from the initial screening ignition time is used as the lower limit of the ignition time optimization interval, and the angle obtained by adding the preset angle to the initial screening ignition time is used as the upper limit of the ignition time optimization interval.
[0112] For example, the specific value range is shown in Table 2:
[0113] Table 2
[0114]
[0115] Taking the working conditions of medium speed (3000rpm) and low load (10%) as an example, the initial screening hydrogen injection time is 414°. The angle obtained by subtracting 10 degrees from the initial screening hydrogen injection time is used as the lower limit of the optimal range of the hydrogen injection time, that is, 404°. The angle obtained by adding 10 degrees to the initial screening hydrogen injection time is used as the upper limit of the optimal range of the hydrogen injection time, that is, 424°. The optimal range of the hydrogen injection time is (404°-424°).
[0116] The angle obtained by subtracting the preset angle from the initial screening ignition moment is used as the lower limit of the ignition moment optimization range, and the angle obtained by adding the preset angle to the initial screening ignition moment is used as the upper limit of the ignition moment optimization range. The preset angle can correspond to different speeds. When the speed is low, the preset angle can be 2 degrees. When the speed is medium, the preset angle can be 4 degrees. When the speed is high, the preset angle can be 6 degrees.
[0117] In step S205, a plurality of mid-screen hydrogen injection timings are determined in the hydrogen injection timing optimization interval, and a plurality of mid-screen ignition timings are determined in the ignition timing optimization interval.
[0118] In some optional embodiments, determining a plurality of mid-screen hydrogen injection times in the hydrogen injection timing optimization interval includes:
[0119] In the hydrogen injection timing optimization interval, 7 middle screen hydrogen injection timings with equal intervals are evenly determined.
[0120] Determining multiple mid-screen ignition times in the ignition time optimization interval includes:
[0121] In the ignition timing optimization interval, seven equally spaced mid-screen ignition times are uniformly determined.
[0122] Taking the medium speed (3000 rpm) and low load (10%) operating conditions as an example, by evenly determining seven equally spaced mid-screen hydrogen injection times within the optimal hydrogen injection timing range (404°-424°), the resulting mid-screen hydrogen injection times are 405°, 408°, 411°, 414°, 417°, 420°, and 423°. By evenly determining seven equally spaced mid-screen hydrogen injection times within the optimal ignition timing range (694°-702°), the resulting mid-screen ignition times are 696°, 697°, 698°, 699°, 700°, 701°, and 702°.
[0123] In step S206, multiple preset hydrogen injection moments included in multiple sets of preset parameters are replaced by multiple mid-screen hydrogen injection moments, and multiple preset ignition moments included in multiple sets of preset parameters are replaced by multiple mid-screen ignition moments to obtain multiple sets of replaced mid-screen parameters.
[0124] In step S207, multiple groups of mid-screen parameters are input as input into the hydrogen internal combustion engine performance simulation model to obtain multiple mid-screen powers, multiple mid-screen thermal efficiencies and multiple mid-screen emission mass fractions as output. The multiple groups of mid-screen parameters include multiple mid-screen hydrogen injection moments and multiple mid-screen ignition moments.
[0125] In step S208, multiple mid-screen hydrogen injection times, multiple mid-screen ignition times, multiple mid-screen powers, multiple mid-screen thermal efficiencies and multiple mid-screen emission mass fractions are fitted to obtain a power function with the ignition time and the hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and the hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and the hydrogen injection time as independent variables and the emission mass fraction as the dependent variable.
[0126] In some optional embodiments, multiple mid-screen hydrogen injection times, multiple mid-screen ignition times, multiple mid-screen powers, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions are fitted to obtain a power function with the ignition time and the hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and the hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and the hydrogen injection time as independent variables and the emission mass fraction as the dependent variable, including:
[0127] The multiple mid-screen powers, multiple mid-screen thermal efficiencies and multiple mid-screen emission mass fractions are dimensionally non-dimensionalized. It can be understood that through the dimensionless processing of the data, the values of power, thermal efficiency and emission mass fraction are at the same dimensional level.
[0128] Regression fitting is performed on multiple mid-screen hydrogen injection moments, multiple mid-screen ignition moments, multiple mid-screen powers after dimensionless processing, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions to obtain the power initial regression model, thermal efficiency initial regression model, and emission initial regression model.
[0129] The power initial regression model, thermal efficiency initial regression model and emission initial regression model were respectively tested for significance, and the insignificant factors in the power initial regression model, thermal efficiency initial regression model and emission initial regression model were eliminated to obtain the optimal power regression model, thermal efficiency optimal regression model and emission optimal regression model. Among them, the power optimal regression model corresponds to the power function with ignition time and hydrogen injection time as independent variables and power as the dependent variable, the thermal efficiency optimal regression model corresponds to the thermal efficiency function with ignition time and hydrogen injection time as independent variables and thermal efficiency as the dependent variable, and the emission optimal regression model corresponds to the emission function with ignition time and hydrogen injection time as independent variables and emission mass fraction as the dependent variable.
[0130] In step S209, a comprehensive optimization function is obtained based on the power function, thermal efficiency function, emission function and preset weights; in some optional embodiments, the weights include three weight groups corresponding to the low-load operating conditions, medium-load operating conditions and high-load operating conditions of the hydrogen internal combustion engine, each weight group includes power weight, thermal efficiency weight and emission weight, and the power weight, thermal efficiency weight and emission weight in different weight groups are not exactly the same.
[0131] In some optional embodiments, the comprehensive optimization function includes a first comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and low load, a second comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and medium load, a third comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and high load, a fourth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and low load, a fifth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and medium load, a sixth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and high load, a seventh comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and low load, an eighth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and medium load, and a ninth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and high load.
[0132] It is understandable that in the performance optimization process of hydrogen internal combustion engines, the ideal optimization effect is to achieve the highest power and economy indicators and the lowest emission indicators. Therefore, the optimization of hydrogen internal combustion engines belongs to a multi-objective function optimization problem. However, achieving the optimal single objective does not necessarily guarantee the optimal overall performance, which makes it almost impossible to find the factor values that simultaneously achieve the highest power and economy of the hydrogen engine and the lowest emissions. This requires that multiple functions be weighted to form a vector as a comprehensive optimization function during the optimization process. The comprehensive optimization function can be expressed using the following formula (1):
[0133] max F(x1,x2)=λ1y1(x1,x2)+λ2y2(x1,x2)-λ3y3(x1,x2) (1)
[0134] Where F(x) is the comprehensive objective function; y1(x1,x2) is the power function, y2(x1,x2) is the thermal efficiency function, and y3(x1,x2) is the emission function; correspondingly, λ1 is the first preset weight of power, λ2 is the second preset weight of thermal efficiency, and λ3 is the third preset weight of emission. The specific preset weights are shown in Table 3:
[0135] Table 3
[0136]
[0137] In step S210 , the comprehensive optimization function is solved to obtain the optimal ignition timing and the optimal hydrogen injection timing.
[0138] It can be understood that for 9 working conditions, 9 comprehensive optimization functions under different working conditions can be obtained respectively. The multi-population genetic algorithm (MPGA) is used to solve the comprehensive optimization function:
[0139] The Sheffield Genetic Algorithm Toolbox was used for the MPGA optimization solution. The initial population size was set to 10, the number of individuals in each population to 40, and the generation gap to 0.9. The crossover and mutation probabilities for each population were randomly generated within the intervals [0.7, 0.9] and [0.001, 0.05], respectively. Furthermore, the optimization termination criterion was that the best individual in the elite population was retained for 10 consecutive generations.
[0140] The optimal hydrogen injection timing and optimal ignition timing of hydrogen internal combustion engines under different working conditions obtained based on MPGA are shown in Table 4:
[0141] Table 4(a) Optimal hydrogen injection time
[0142]
[0143] (b) Optimal ignition timing
[0144]
[0145] It can be understood that the optimal ignition timing and the optimal hydrogen injection timing obtained in step S210 correspond to the most accurate ignition timing and hydrogen injection timing under different operating conditions of the hydrogen internal combustion engine.
[0146] In step S211 , the hydrogen internal combustion engine is controlled according to the optimal ignition timing and the optimal hydrogen injection timing.
[0147] The hydrogen internal combustion engine performance optimization method provided by the present application is adopted, and a full test scheme and a preset ignition moment and a preset hydrogen injection moment are used to obtain a more accurate optimization interval of the ignition moment and the hydrogen injection moment. Then, a uniform test scheme is used to determine multiple mid-screen ignition moments and multiple mid-screen hydrogen injection moments from the optimization interval of the ignition moment and the hydrogen injection moment, and multiple parameters including multiple mid-screen ignition moments and multiple mid-screen hydrogen injection moments are input into the hydrogen internal combustion engine performance simulation model to obtain multiple output powers, multiple efficiencies and multiple emission mass fractions. The input and output quantities are fitted to obtain the ignition moment and hydrogen injection moment as the optimal interval. The invention relates to a method for optimizing the performance of a hydrogen internal combustion engine by optimizing the timing of ignition and the timing of hydrogen injection. The method comprises the following steps: a power function with power as the dependent variable, a thermal efficiency function with ignition timing and hydrogen injection timing as independent variables and thermal efficiency as the dependent variable, and an emission function with ignition timing and hydrogen injection timing as independent variables and emission mass fraction as the dependent variable. According to these functions and preset weights, a comprehensive optimization function is obtained. The comprehensive optimization function reflects the influence of ignition timing and hydrogen injection timing on the comprehensive performance of the hydrogen internal combustion engine under specific working conditions. The optimal ignition timing and the optimal hydrogen injection timing can be obtained by solving the comprehensive optimization function. The performance of the hydrogen internal combustion engine can be improved by controlling the hydrogen internal combustion engine according to the optimal ignition timing and the optimal hydrogen injection timing.
[0148] The present application also provides a hydrogen internal combustion engine performance optimization device, such as Figure 4 As shown, the hydrogen internal combustion engine performance optimization device 40 includes a processor 401, a memory 402, and a computer program stored in the memory 402 and executable on the processor 401, and is characterized in that when the computer program is executed by the processor 401, the hydrogen internal combustion engine performance optimization method provided in the previous embodiment is implemented.
[0149] The present application also provides a computer-readable storage medium, such as a memory including program code, wherein the program code can be executed by a processor of a hydrogen internal combustion engine performance optimization device to perform the hydrogen internal combustion engine performance optimization method of the above embodiment. For example, the computer-readable storage medium can be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CD-ROM), a magnetic tape, a floppy disk, an optical data storage device, etc.
[0150] Those skilled in the art will understand that all or part of the steps of implementing the above embodiments can be completed by hardware, or by hardware related to program code, and the program can be stored in a computer-readable storage medium. The above-mentioned storage medium can be a read-only memory, a disk or an optical disk, etc.
[0151] In this application, it should be understood that the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features.
[0152] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only.
[0153] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.
[0154] The above description is only for the purpose of facilitating those skilled in the art to understand the technical solution of this application and is not intended to limit this application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included in the scope of protection of this application.
Claims
1. A method for optimizing the performance of a hydrogen internal combustion engine, characterized in that: The method comprises: Establish a hydrogen internal combustion engine performance simulation model; Inputting multiple sets of mid-screen parameters as inputs into the hydrogen internal combustion engine performance simulation model to obtain multiple mid-screen powers, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions as outputs, the multiple sets of mid-screen parameters including multiple mid-screen hydrogen injection moments and multiple mid-screen ignition moments; Fitting the multiple mid-screen hydrogen injection times, the multiple mid-screen ignition times, the multiple mid-screen powers, the multiple mid-screen thermal efficiencies, and the multiple mid-screen emission mass fractions to obtain a power function with the ignition time and the hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and the hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and the hydrogen injection time as independent variables and the emission mass fraction as the dependent variable; Obtaining a comprehensive optimization function according to the power function, the thermal efficiency function, the emission function, and preset weights; Solving the comprehensive optimization function to obtain the optimal ignition timing and the optimal hydrogen injection timing; The hydrogen internal combustion engine is controlled according to the optimal ignition timing and the optimal hydrogen injection timing.
2. The method for optimizing the performance of a hydrogen internal combustion engine according to claim 1, characterized in that: Inputting multiple sets of mid-screen parameters as inputs into the hydrogen internal combustion engine performance simulation model to obtain multiple mid-screen powers, multiple mid-screen thermal efficiencies, and multiple mid-screen emission mass fractions as outputs, wherein the multiple sets of mid-screen parameters include multiple mid-screen hydrogen injection moments and multiple mid-screen ignition moments. The method further includes: Inputting multiple sets of preset parameters as inputs into the hydrogen internal combustion engine performance simulation model to obtain multiple preliminary screening powers, multiple preliminary screening thermal efficiencies, and multiple preliminary screening emission mass fractions as outputs, the multiple sets of preset parameters including multiple preset hydrogen injection times and multiple preset ignition times; Determining a primary screening hydrogen injection time from the plurality of preset hydrogen injection times and determining a primary screening ignition time from the plurality of preset ignition times according to the maximum value of the plurality of primary screening powers, the maximum value of the plurality of primary screening thermal efficiencies, and the maximum value of the plurality of primary screening emission mass fractions; Determine an optimal hydrogen injection time interval near the primary screening hydrogen injection time, and determine an optimal ignition time interval near the primary screening ignition time; Determining a plurality of mid-screen hydrogen injection timings in the hydrogen injection timing optimization interval, and determining a plurality of mid-screen ignition timings in the ignition timing optimization interval; The multiple mid-screen hydrogen injection moments are used to replace the multiple preset hydrogen injection moments included in the multiple sets of preset parameters, and the multiple mid-screen ignition moments are used to replace the multiple preset ignition moments included in the multiple sets of preset parameters to obtain the replaced multiple sets of mid-screen parameters.
3. The method for optimizing the performance of a hydrogen internal combustion engine according to claim 2, wherein: The plurality of sets of preset parameters include nine sets of preset parameters corresponding one to one with nine operating conditions of the hydrogen internal combustion engine, the nine operating conditions including: The hydrogen internal combustion engine is at low speed and low load, the hydrogen internal combustion engine is at low speed and medium load, the hydrogen internal combustion engine is at low speed and high load, the hydrogen internal combustion engine is at medium speed and low load, the hydrogen internal combustion engine is at medium speed and medium load, the hydrogen internal combustion engine is at medium speed and high load, the hydrogen internal combustion engine is at high speed and low load, the hydrogen internal combustion engine is at high speed and medium load, and the hydrogen internal combustion engine is at high speed and high load, wherein each operating condition corresponds to 4 preset hydrogen injection times and 4 preset ignition times, and the 4 preset hydrogen injection times corresponding to different operating conditions are exactly the same.
4. The method for optimizing the performance of a hydrogen internal combustion engine according to claim 3, characterized in that: The operating condition of the hydrogen internal combustion engine at high speed and high load corresponds to two preset hydrogen injection times and four preset ignition times.
5. The method for optimizing the performance of a hydrogen internal combustion engine according to claim 2, characterized in that: The unit of the ignition timing and the hydrogen injection timing is angle, wherein determining the optimal interval for hydrogen injection timing near the primary screening hydrogen injection timing includes: The angle obtained by subtracting 10 degrees from the initial screening hydrogen injection time is used as the lower limit of the hydrogen injection time optimization interval, and the angle obtained by adding 10 degrees to the initial screening hydrogen injection time is used as the upper limit of the hydrogen injection time optimization interval. Determining the ignition timing optimization interval near the primary screening ignition timing includes: The angle obtained by subtracting the preset angle from the initial screening ignition moment is used as the lower limit of the ignition moment optimization interval, and the angle obtained by adding the preset angle to the initial screening ignition moment is used as the upper limit of the ignition moment optimization interval.
6. The method for optimizing the performance of a hydrogen internal combustion engine according to claim 1, wherein: Determining a plurality of mid-screen hydrogen injection times in the hydrogen injection time optimization interval includes: In the hydrogen injection timing optimization interval, 7 equally spaced mid-screen hydrogen injection timings are uniformly determined. Determining a plurality of mid-screen ignition times in the ignition time optimization interval includes: In the ignition timing optimization interval, seven mid-screen ignition timings with equal intervals are evenly determined.
7. The method for optimizing the performance of a hydrogen internal combustion engine according to claim 1, wherein: The multiple mid-screen hydrogen injection times, the multiple mid-screen ignition times, the multiple mid-screen powers, the multiple mid-screen thermal efficiencies, and the multiple mid-screen emission mass fractions are fitted to obtain a power function with the ignition time and the hydrogen injection time as independent variables and the power as the dependent variable, a thermal efficiency function with the ignition time and the hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and an emission function with the ignition time and the hydrogen injection time as independent variables and the emission mass fraction as the dependent variable, including: Performing dimensionless processing on the multiple mid-screen powers, the multiple mid-screen thermal efficiencies, and the multiple mid-screen emission mass fractions; Performing regression fitting on the multiple mid-screen hydrogen injection moments, the multiple mid-screen ignition moments, and the multiple mid-screen powers, the multiple mid-screen thermal efficiencies, and the multiple mid-screen emission mass fractions after dimensionless processing to obtain an initial power regression model, an initial thermal efficiency regression model, and an initial emission regression model; The power initial regression model, the thermal efficiency initial regression model and the emission initial regression model are respectively subjected to significance checks, and the insignificant factors in the power initial regression model, the thermal efficiency initial regression model and the emission initial regression model are eliminated to obtain the power optimal regression model, the thermal efficiency optimal regression model and the emission optimal regression model, wherein the power optimal regression model corresponds to the power function with the ignition time and the hydrogen injection time as independent variables and the power as the dependent variable, the thermal efficiency optimal regression model corresponds to the thermal efficiency function with the ignition time and the hydrogen injection time as independent variables and the thermal efficiency as the dependent variable, and the emission optimal regression model corresponds to the emission function with the ignition time and the hydrogen injection time as independent variables and the emission mass fraction as the dependent variable.
8. The method for optimizing the performance of a hydrogen internal combustion engine according to claim 1, wherein: The weights include three weight groups corresponding to the low-load operating conditions, medium-load operating conditions and high-load operating conditions of the hydrogen internal combustion engine. Each weight group includes a power weight, a thermal efficiency weight and an emission weight. The power weight, the thermal efficiency weight and the emission weight in different weight groups are not exactly the same.
9. The method for optimizing the performance of a hydrogen internal combustion engine according to claim 1, wherein: The comprehensive optimization function includes a first comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and low load, a second comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and medium load, a third comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at low speed and high load, a fourth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and low load, a fifth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and medium load, a sixth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at medium speed and high load, a seventh comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and low load, an eighth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and medium load, and a ninth comprehensive optimization function corresponding to the working condition of the hydrogen internal combustion engine at high speed and high load.
10. A hydrogen internal combustion engine performance optimization device, comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, characterized in that: When the computer program is executed by the processor, the method according to any one of claims 1 to 9 is implemented.