Matching method and matching device of electric supercharger under transient working condition of engine

Abstract

This application provides a matching method and device for an electric supercharger under transient engine conditions. The electric supercharger is used to compensate for insufficient intake air in the engine's original turbocharger under transient conditions. The matching method includes: determining the target intake air flow rate, target intake air pressure, and target power required to compress air from the initial intake pressure to the target intake pressure based on the fuel injection quantity and predetermined equivalence ratio of the engine under a target transient condition of constant speed sudden loading, where the initial intake pressure is the initial ambient pressure at the inlet of the engine intake manifold; performing simulation calculations of the engine combustion process based on the fuel injection quantity and predetermined equivalence ratio to determine the target pre-turbo exhaust gas index before the engine exhaust reaches the turbocharger; determining the target performance index of the electric supercharger based on the target pre-turbo exhaust gas index; and determining the target electric supercharger based on the target performance index of the electric supercharger.

Description

Technical Field

[0001] This application relates to the field of turbocharging technology, and more specifically, to a matching method and matching device for an electric turbocharger under transient engine conditions. Background Technology

[0002] During the operation of engines such as diesel engines, transient conditions are one of the typical operating conditions. Under these conditions, the engine load increases rapidly, the fuel injection quantity increases sharply, and the demand for intake air also increases instantaneously. However, the turbocharger originally equipped in the engine is affected by turbo lag, resulting in a slow response speed and an inability to provide the required intake air volume in a timely manner, leading to insufficient intake air. Insufficient intake air can cause problems such as a rich air-fuel mixture, incomplete combustion, increased fuel consumption, and worsened emissions (such as smoke and excessive NOx emissions), seriously affecting the engine's transient performance and operational stability.

[0003] Currently, there is a lack of scientific and systematic methods for matching electric superchargers. Most selections rely on experience and cannot accurately match the intake requirements of the engine under transient operating conditions. Summary of the Invention

[0004] In view of this, this application provides a matching method and matching device for an electric supercharger under transient engine conditions.

[0005] One aspect of this application provides a matching method for an electric supercharger under transient engine conditions. The electric supercharger is used to compensate for insufficient intake air in the engine's original turbocharger under transient conditions. The matching method includes: determining the target intake air flow rate, target intake air pressure, and target power required to compress air from the initial intake pressure to the target intake pressure based on the fuel injection quantity and predetermined equivalence ratio of the engine under a target transient condition of constant speed sudden loading. The initial intake pressure is the initial ambient pressure at the inlet of the engine intake manifold. Simulation calculations of the engine combustion process are performed based on the fuel injection quantity and predetermined equivalence ratio to determine the target pre-turbo exhaust gas index before the turbocharger. Based on the target pre-turbo exhaust gas index, the target performance index of the electric supercharger is determined, including the target power index of the electric supercharger's motor, the target pressure ratio index of the electric supercharger's compressor, and the target flow rate index. Finally, a target electric supercharger is determined based on the target performance index of the electric supercharger.

[0006] According to an embodiment of this application, the target turbocharger exhaust index includes the target turbocharger exhaust temperature. The target turbocharger exhaust index is determined by simulating the engine combustion process based on the fuel injection quantity and a predetermined equivalence ratio, and then determining the target turbocharger exhaust index of the exhaust gas before it reaches the turbocharger. This includes: simulating the engine combustion process based on the fuel injection quantity and a predetermined equivalence ratio to determine the proportion of fuel energy entering the exhaust gas; determining the steady-state temperature rise under steady-state conditions based on the fuel energy proportion and the temperature rise per unit fuel energy; constructing a temperature rise correction that decays exponentially with time based on the initial temperature rise, the final temperature rise, and a time constant characterizing the exhaust manifold preheating delay, where the initial temperature rise is the engine's steady-state exhaust temperature rise at idle or no-load before the start of transient conditions, and the final temperature rise is the engine's exhaust temperature rise at the target load steady state after the end of transient conditions; and determining the target turbocharger exhaust temperature based on the steady-state temperature rise, the temperature rise correction, and the engine intake temperature.

[0007] According to embodiments of this application, the target turbine inlet exhaust index further includes the target turbine inlet exhaust flow rate and the target turbine inlet exhaust pressure. Based on the fuel injection quantity and a predetermined equivalence ratio, the engine combustion process is simulated and calculated to determine the turbine inlet exhaust index of the exhaust gas emitted by the engine before reaching the turbocharger. This includes: determining the target turbine inlet exhaust flow rate of the engine under the condition of the target intake flow rate, based on the target intake flow rate and a predetermined conversion coefficient characterizing the intake and exhaust volumes of the engine; and using the matching relationship between the output power of the turbine in the turbocharger and the input power of the compressor in the turbocharger, based on the target turbine inlet exhaust flow rate, the target turbine inlet exhaust temperature, and the turbine efficiency, to inversely deduce the target turbine inlet exhaust pressure that meets the target power requirement.

[0008] According to embodiments of this application, the target performance indicators of the electric supercharger are determined based on the target in-turbo exhaust indicators, including: performing simulation calculations of the engine combustion process based on the fuel injection quantity and actual equivalence ratio of the engine under target transient operating conditions to determine the actual in-turbo exhaust indicators of the exhaust gas emitted by the engine before reaching the turbocharger; determining the target pressure ratio and target flow rate of the compressor of the electric supercharger based on the target in-turbo exhaust pressure and target in-turbo flow rate in the target in-turbo exhaust indicators, and based on the actual in-turbo exhaust pressure and actual in-turbo flow rate in the actual in-turbo exhaust indicators; and determining the target matching power of the motor of the electric supercharger based on the target required power and the transient output power of the turbocharger determined based on the actual in-turbo exhaust indicators.

[0009] According to an embodiment of this application, determining the target matching power of the electric supercharger based on the target required power and the transient output power of the turbocharger determined based on the actual turbocharger exhaust index includes: determining the initial target matching power based on the difference between the target required power and the transient output power of the turbocharger; and determining the target matching power based on the initial target matching power and the estimated efficiency of the electric supercharger.

[0010] According to embodiments of this application, the method further includes: determining multiple combinations of fuel injection quantities and predetermined equivalence ratios for the engine under target transient operating conditions based on a first boundary condition of the fuel injection quantity and a second boundary condition of the predetermined equivalence ratio; determining the target power range of the electric supercharger's motor, the target pressure range of the electric supercharger's compressor, and the target flow range of the electric supercharger based on multiple target pre-turbo exhaust indices determined by the combinations of the multiple fuel injection quantities and predetermined equivalence ratios; determining multiple candidate electric superchargers based on the target power range, target pressure ratio range, and target flow range of the electric supercharger; performing simulated intake compensation simulation on the multiple candidate electric superchargers under the target transient operating conditions to determine the boost efficiency of each of the multiple candidate electric superchargers; and determining the target electric supercharger based on the overall efficiency of each of the multiple candidate electric superchargers.

[0011] According to an embodiment of this application, the method includes: performing simulated intake compensation simulation on the target electric supercharger under multiple transient operating conditions of constant speed sudden loading, and determining the target operating power of the target electric supercharger under each of the multiple transient operating conditions; and determining the transient operating strategy of the target electric supercharger based on the target operating power of the target electric supercharger under each of the multiple transient operating conditions.

[0012] According to an embodiment of this application, the target intake air flow rate required by the engine is determined based on the fuel injection quantity and predetermined equivalence ratio under the target transient operating condition of constant speed sudden loading. This includes determining the target intake air flow rate based on the engine's effective power and effective fuel consumption rate determined by the fuel injection quantity, the excess air coefficient corresponding to the predetermined equivalence ratio, and the scavenging coefficient.

[0013] According to an embodiment of this application, the target intake pressure required by the engine is determined based on the fuel injection quantity and a predetermined equivalence ratio under the target transient operating condition of constant speed sudden loading. This includes: determining the engine's mean effective pressure, effective fuel consumption rate, excess air coefficient, cylinder charge coefficient, and intake temperature based on the fuel injection quantity, and determining the initial intake pressure; and determining the target intake pressure based on the initial intake pressure and a preset pressure correction amount.

[0014] Another aspect of this application provides a matching device for an electric supercharger under transient engine conditions. The electric supercharger is used to compensate for insufficient intake air in the case of insufficient intake air in the original turbocharger of the engine under transient conditions. The matching device includes: a first determining module, used to determine the target intake air flow rate, target intake air pressure, and target required power to compress air from the initial intake pressure to the target intake pressure based on the fuel injection quantity and predetermined equivalence ratio of the engine under the target transient condition of constant speed sudden loading. The initial intake pressure is the initial ambient pressure at the inlet of the engine intake manifold; a second determining module, used to perform simulation calculations of the engine combustion process based on the fuel injection quantity and predetermined equivalence ratio to determine the target pre-turbo exhaust gas index of the exhaust gas before it reaches the turbocharger; a third determining module, used to determine the target performance index of the electric supercharger based on the target pre-turbo exhaust gas index. The target performance index includes the power index of the electric supercharger motor, the pressure ratio index of the electric supercharger compressor, and the flow rate index; and a fourth determining module, used to determine the target electric supercharger based on the target performance index of the electric supercharger.

[0015] According to the embodiments of this application, by taking the transient operating condition of constant speed engine sudden loading as the core, and combining the fuel injection quantity and predetermined equivalence ratio, the target intake air demand and target power demand of the engine are accurately determined. At the same time, the target turbine exhaust index is obtained through simulation calculation, realizing the accurate derivation of the target performance index of the electric turbocharger, and solving the problem of low accuracy and reliance on experience in matching electric turbochargers in the prior art. Attached Figure Description

[0016] The above and other objects, features and advantages of this application will become clearer from the following description of embodiments with reference to the accompanying drawings, in which:

[0017] Figure 1 This is a flowchart illustrating a matching method for an electric supercharger under transient engine conditions according to an embodiment of this application;

[0018] Figure 2 A schematic diagram of an electric supercharger structure according to an embodiment of this application is shown;

[0019] Figure 3 A flowchart of an electric supercharger matching method according to an embodiment of this application is shown;

[0020] Figure 4 A block diagram of a matching device for an electric supercharger under transient engine conditions, according to an embodiment of this application, is shown.

[0021] Figure 5 A schematic block diagram is shown of an electronic device suitable for implementing an electric supercharger matching method, which can be used to carry out embodiments of this application. Detailed Implementation

[0022] The embodiments of this application will now be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of this application. In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments of this application for ease of explanation. However, it will be apparent that one or more embodiments may be implemented without these specific details. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concepts of this application.

[0023] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application. The terms “comprising,” “including,” etc., as used herein indicate the presence of features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0024] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0025] When using expressions such as "at least one of A, B and C", they should generally be interpreted in accordance with the meaning that is commonly understood by those skilled in the art (e.g., "a system having at least one of A, B and C" should include, but is not limited to, a system having A alone, a system having B alone, a system having C alone, a system having A and B, a system having A and C, a system having B and C, and / or a system having A, B and C, etc.).

[0026] Turbocharging technology can improve engine power, economy, and compactness. Traditional turbochargers rely on recovering exhaust energy to drive the compressor, and the build-up of exhaust pressure during transient processes takes time, resulting in transient response lag and black smoke emissions. The worst carbon emissions from diesel engines occur during transient sudden loading, primarily due to air system lag causing an imbalance in fuel supply and intake air ratio, leading to an oxygen equivalence ratio exceeding the critical value.

[0027] Electric supercharging technology uses a high-speed electric motor to directly drive the compressor, offering advantages such as rapid acceleration response, high adjustment flexibility, and high boosting efficiency. It eliminates the dependence of traditional turbochargers on exhaust energy, significantly improving intake pressure and charge responsiveness, and substantially enhancing low-speed torque and acceleration. Simultaneously, the electric supercharging system is decoupled from the original engine, allowing for supplemental air intake without modification. It can be integrated into the intake manifold, either upstream or downstream of the turbocharger system, to achieve this function. Because electric superchargers are significantly affected by temperature, placing them downstream of the turbocharger requires an interstage cooler to reduce heat load, increasing structural complexity and cost. Therefore, placing the electric supercharger upstream of the turbocharger is chosen, resulting in a simpler structure and easier modification.

[0028] Currently, research on matching methods for electric turbocharger systems mainly focuses on steady-state operating conditions, lacking attention to the electric turbocharger requirements during transient processes. By transiently matching the electric turbocharger with the diesel engine, equivalence ratio control under transient conditions can be achieved, reducing carbon emissions during transient processes. This provides technical support for internal combustion engines to meet increasingly stringent emission regulations and is of great significance for achieving dual-carbon goals.

[0029] In view of the above, this application provides a matching method and matching device for an electric supercharger under transient engine conditions, wherein the electric supercharger is used to compensate for insufficient intake air when the original turbocharger of the engine is under transient conditions.

[0030] Figure 1 This is a flowchart illustrating a matching method for an electric supercharger under transient engine conditions according to an embodiment of this application.

[0031] like Figure 1 As shown, the matching method includes operations S110 to S140.

[0032] In operation S110, based on the fuel injection quantity and predetermined equivalence ratio of the engine under the target transient operating condition of constant speed sudden loading, the target intake air flow rate, target intake air pressure, and target required power to compress the air at the initial intake pressure to the target intake pressure are determined. The initial intake pressure is the initial ambient pressure at the inlet of the engine intake manifold.

[0033] In operation of S120, the engine combustion process is simulated and calculated based on the fuel injection quantity and the predetermined equivalence ratio to determine the target pre-turbo exhaust index of the exhaust gas emitted by the engine before reaching the turbocharger.

[0034] In operation S130, based on the target turbine exhaust index, the target performance index of the electric supercharger is determined. The target performance index includes the target power index of the electric supercharger motor, the target pressure ratio index of the electric supercharger compressor, and the target flow rate index.

[0035] In operation S140, the target electric supercharger is determined based on the target performance indicators of the electric supercharger.

[0036] Transient operating conditions of engines such as diesel engines mainly include three basic transient processes: constant speed loading, constant load speed change, and cold / hot start. The constant speed sudden loading condition, due to the lag in the air system response, leads to a momentary imbalance in the air-fuel ratio, resulting in the most severe carbon emissions. Therefore, in the embodiments of this application, this process can be selected as the transient matching condition for the electric turbocharger.

[0037] Because diesel engines have ample intake air at high speeds, and the high exhaust energy ensures efficient turbocharger operation, electric supercharger assistance is not a necessary option. Therefore, for transient matching conditions, low-speed operation can be selected. Under this condition, insufficient intake air is the main problem, requiring timely transient air replenishment from the electric supercharger to improve engine performance.

[0038] The target transient condition can be selected as a condition with a large load change under constant speed. For example, the target transient condition can be selected as a sudden load increase from 0 to 90% within 1 second during a constant speed loading process at an engine speed of 950 r / min.

[0039] For example, the transient injection quantity curve can be obtained by interpolation based on the engine steady-state injection quantity MAP, and then the injection quantity for the target transient operating condition can be obtained. The predetermined equivalence ratio can be set to the equivalence ratio that satisfies the normal combustion of the engine, corresponding to an excess air coefficient of 1.25 to 1.4.

[0040] For example, the amount of fuel injection and the predetermined equivalence ratio can be used as the core basis, combined with the engine combustion characteristics, to calculate the amount of air required for normal engine combustion, and then determine the target intake air flow rate; at the same time, based on the amount of fuel injection and the predetermined equivalence ratio, combined with the engine mean effective pressure and the intake environment, the target intake pressure can be determined; the initial intake pressure (the initial ambient pressure at the engine intake manifold inlet, i.e., the initial ambient pressure at the engine intake manifold inlet) can be used as the initial benchmark, combined with transient intake demand, to finally determine the target intake air flow rate and the target intake pressure.

[0041] For example, a simulation model of the engine combustion process can be constructed using engine combustion simulation tools based on the determined fuel injection quantity and predetermined equivalence ratio under the target transient condition of constant speed sudden loading. Through simulation calculations, the target turbine inlet exhaust index of the exhaust gas before reaching the turbocharger inlet (i.e., the turbine front end) can be determined. The target turbine inlet exhaust index is a core parameter characterizing the energy, flow rate, and pressure characteristics of the exhaust gas, including at least the turbine inlet exhaust temperature, and may further include parameters such as the target turbine inlet exhaust flow rate and the target turbine inlet exhaust pressure.

[0042] Based on the target turbocharger exhaust performance indicators, and combined with the engine's target intake air requirements and the actual air supply capacity of the existing turbocharger, the target performance indicators of the electric supercharger can be deduced in reverse. The target power indicator of the electric motor is used to determine the power output of the electric supercharger motor to ensure that it can meet the energy requirements for supplementing the engine's intake air demand; the target pressure ratio indicator of the compressor is used to determine the boost capacity that the compressor needs to achieve to ensure that the air can be compressed to the pressure level required for engine combustion; the target flow rate indicator of the compressor is used to determine the air flow rate that the electric supercharger needs to provide to ensure that it can make up for the intake gap of the existing turbocharger.

[0043] By identifying target performance indicators, electric superchargers that meet all the requirements can be selected. This means determining the target electric supercharger that meets the engine's transient intake compensation needs and is perfectly matched with the target performance indicators. This achieves precise adaptation between the electric supercharger and the engine's transient operating conditions and the original turbocharger, ensuring that the electric supercharger can effectively supplement the insufficient intake of the original turbocharger, guaranteeing stable and efficient engine combustion, while also taking into account the operating efficiency and practical application feasibility of the electric supercharger.

[0044] According to the embodiments of this application, by taking the transient operating condition of constant speed engine sudden loading as the core, and combining the fuel injection quantity and predetermined equivalence ratio, the target intake air demand and target power demand of the engine are accurately determined. At the same time, the target turbine exhaust index is obtained through simulation calculation, realizing the accurate derivation of the target performance index of the electric turbocharger, and solving the problem of low accuracy and reliance on experience in matching electric turbochargers in the prior art.

[0045] For heavy-duty diesel engines, the above method allows for flexible control of the electric motor speed during transient processes, enabling supplemental air intake based on the engine's actual intake conditions. Because the intake flow rate is significantly increased during transient processes, the demands of in-cylinder combustion are met, resulting in a significant reduction in pollutant emissions. Furthermore, the electric motor's operation is unaffected by the inertia of the turbine and shaft, and electric supercharging technology can significantly improve the engine's low-speed transient response performance. Simultaneously, because the motor is located far from the turbocharger, it is less affected by the high-temperature exhaust gas at the turbine end, and the motor can be independently controlled without being affected by the turbocharger's operating state, thus broadening the engine's flow range.

[0046] According to embodiments of this application, an electric supercharger can be installed upstream or downstream of a turbocharger system and connected to the intake manifold to achieve a supplemental air function.

[0047] Since electric superchargers are greatly affected by temperature, placing them downstream of turbochargers requires an interstage cooler to reduce the heat load, which increases structural complexity and cost. Therefore, the design of placing the electric supercharger upstream of the turbocharger is chosen, which is simple in structure and easy to modify.

[0048] Figure 2A schematic diagram of an electric supercharger structure according to an embodiment of this application is shown.

[0049] like Figure 2 As shown, the electric booster unit includes a high-speed motor 1, a left fixed support 2 and a right fixed support 3, a base 4, a coupling 5, a compressor 6, and its fixed support 7. The high-speed motor 1 serves as the power source and is directly connected to the rotor shaft of the compressor 6 via the coupling 5, forming a rigid transmission chain. The left fixed support 2 and the right fixed support 3 are symmetrically arranged on both sides of the high-speed motor and are rigidly connected to the base 4 via bolts, fixing the motor position and bearing the radial and axial forces generated during motor operation. The compressor fixed support 7 independently supports the compressor housing and is flexibly connected to the base 4 via shock-absorbing pads, isolating compressor vibration and limiting its displacement to avoid resonance.

[0050] The design, which places the electric supercharger upstream of the turbocharger, is simple in structure and easy to modify the pipeline, while avoiding the impact of high-temperature heat load on the reliability of the motor.

[0051] Because the operation of the electric motor is unaffected by the inertia of the turbine and shaft, electric supercharging technology can significantly improve the low-speed transient response performance of the engine. Simultaneously, since the motor is far from the turbocharger, it is less affected by the high-temperature exhaust gas at the turbine end, and the motor can be independently controlled without being affected by the turbocharger's operating state, thus widening the engine's flow range. Therefore, using this method, the supercharging effect of the electric supercharger is separated from the exhaust energy, effectively improving the intake supercharging effect at low engine speeds, improving engine performance, and reducing turbo lag. When replacing the electric supercharger, the electric motor, compressor, and coupling can be replaced to meet different needs, achieving decoupling from the original engine and effectively reducing parts replacement and maintenance costs.

[0052] According to an embodiment of this application, determining the target intake air flow required by the engine based on the fuel injection quantity and predetermined equivalence ratio under the target transient operating condition of constant speed sudden loading may include: determining the target intake air flow based on the engine's effective power and effective fuel consumption rate determined by the fuel injection quantity, the excess air coefficient corresponding to the predetermined equivalence ratio, and the scavenging coefficient.

[0053] For example, the formula for calculating the target intake air volume is as follows:

[0054] (1)

[0055] Where, q mb Indicates the target intake airflow. The effective power of the engine. For effective fuel consumption rate, The excess air coefficient, This is the scavenging coefficient.

[0056] Determining the target intake pressure required by the engine based on the fuel injection quantity and predetermined equivalence ratio under the target transient operating condition of constant speed sudden loading can include: determining the engine's mean effective pressure, effective fuel consumption rate, excess air coefficient, cylinder charge coefficient, and intake temperature based on the fuel injection quantity, and determining the initial intake pressure; and determining the target intake pressure based on the initial intake pressure and a preset pressure correction amount.

[0057] For example, the formula for calculating the initial intake pressure is as follows:

[0058] (2)

[0059] Among them, the initial intake pressure , The excess air coefficient, This is the scavenging coefficient. For average effective pressure, Intake air temperature, For effective fuel consumption rate, This is the cylinder charge coefficient.

[0060] For example, the formula for calculating the target intake pressure is as follows:

[0061] (3)

[0062] in, Indicates intake pressure, This indicates the initial intake pressure.

[0063] According to embodiments of this application, the target turbocharger exhaust index includes the target turbocharger exhaust temperature. The target turbocharger exhaust index, determined by simulating the engine combustion process based on the fuel injection quantity and a predetermined equivalence ratio, can include: simulating the engine combustion process based on the fuel injection quantity and a predetermined equivalence ratio to determine the proportion of fuel energy entering the exhaust gas; determining the steady-state temperature rise under steady-state conditions based on the fuel energy proportion and the temperature rise per unit fuel energy; constructing a temperature rise correction that decays exponentially with time based on the initial temperature rise, the final temperature rise, and a time constant characterizing the exhaust manifold preheating delay, where the initial temperature rise is the engine's steady-state exhaust temperature rise at idle or no-load before the start of transient conditions, and the final temperature rise is the engine's exhaust temperature rise at the target load steady state after the end of transient conditions; and determining the target turbocharger exhaust temperature based on the steady-state temperature rise, the temperature rise correction, and the engine intake temperature.

[0064] The percentage of fuel energy entering the exhaust gas represents the proportion of fuel energy that is not used for effective work in the engine cylinders and is directly discharged with the exhaust gas, relative to the total injected fuel energy. Engine combustion simulation tools can be used to construct a combustion process simulation model to simulate the entire process of fuel atomization, mixing, combustion, and exhaust gas generation within the engine cylinders. The percentage of fuel energy entering the exhaust gas can then be determined through simulation analysis.

[0065] The temperature increase corresponding to a unit of fuel energy can be calculated from the fuel's constant-pressure lower calorific value, relative thermal efficiency, and exhaust gas constant-pressure specific heat, characterizing the extent to which a unit mass of fuel energy can increase the exhaust gas temperature.

[0066] The steady-state temperature rise characterizes the increase in exhaust temperature caused by the fuel energy entering the exhaust gas under steady-state operating conditions. The formula for calculating the steady-state temperature rise is as follows:

[0067] (4)

[0068] in, For steady-state temperature rise, The proportion of injected energy in the fuel entering the exhaust gas. For global air-fuel ratio, For constant pressure and low calorific value, For relative thermal efficiency, It is a specific heat at constant pressure.

[0069] The initial temperature rise can be calculated from the injection quantity and equivalence ratio under idling or no-load conditions; the final temperature rise can be calculated from the injection quantity and predetermined equivalence ratio under the target load condition. The time constant of the exhaust manifold preheating delay can be determined by the exhaust manifold size, structure, and exhaust gas energy. Based on the initial temperature rise, the final temperature rise, and this time constant, a temperature rise correction factor that decays exponentially with time is constructed. This correction factor is used to compensate for the exhaust temperature rise delay effect caused by the thermal inertia of the exhaust manifold, making the calculation results more consistent with the actual transient operation of the engine. Temperature rise correction factor The calculation formula is as follows:

[0070] (5)

[0071] In the formula, , This represents the steady-state temperature increase. This is the initial temperature increase. This is the final temperature increase. The exhaust manifold time constant represents the preheating delay period.

[0072] For example, the actual temperature increase under transient conditions can be obtained by subtracting the constructed temperature increase correction from the steady-state temperature increase. This transient temperature increase is then superimposed on the engine intake temperature to finally calculate the target turbine inlet exhaust temperature before the engine exhaust reaches the turbocharger.

[0073] Target turbine inlet exhaust temperature The calculation formula is as follows:

[0074] (6)

[0075] in, This is the intake air temperature after intercooling, which is also the engine intake air temperature.

[0076] According to the embodiments of this application, by combining the fuel injection quantity and a predetermined equivalence ratio to simulate the engine combustion process, the proportion of fuel energy entering the exhaust gas is determined, and the steady-state temperature rise is determined based on the proportion of fuel energy and the temperature rise per unit fuel energy. Furthermore, a temperature rise correction amount that decays exponentially with time is established. This can effectively solve the problem of exhaust temperature rise delay caused by exhaust manifold thermal inertia under transient operating conditions, so that the calculated exhaust temperature rise can truly reflect the actual temperature change law during the transient operation of the engine. It avoids the problem of overestimating or underestimating the turbine exhaust temperature due to ignoring the influence of thermal inertia, improves the accuracy of temperature calculation, and fits the actual operating conditions of engine transient operation.

[0077] According to embodiments of this application, the target turbine inlet exhaust index further includes the target turbine inlet exhaust flow rate and the target turbine inlet exhaust pressure. Based on simulation calculations of the engine combustion process using the fuel injection quantity and a predetermined equivalence ratio, determining the turbine inlet exhaust index of the exhaust gas emitted from the engine before reaching the turbocharger may include: determining the target turbine inlet exhaust flow rate of the engine under the condition of the target intake flow rate, based on the target intake flow rate and a predetermined conversion coefficient characterizing the engine's intake and exhaust volumes; and, based on the target turbine inlet exhaust flow rate, the target turbine inlet exhaust temperature, and the turbine efficiency, using the matching relationship between the output power of the turbine in the turbocharger and the input power of the compressor in the turbocharger, back-calculating the target turbine inlet exhaust pressure to meet the target power requirement.

[0078] The predetermined conversion coefficient can be determined based on the engine's combustion stoichiometry, scavenging coefficient, and combustion completeness. It is used to convert the target intake flow rate on the intake side into the target turbine inlet exhaust flow rate on the exhaust side. In the embodiments of this application, the predetermined conversion coefficient can be 1.02 to 1.03.

[0079] Turbine efficiency characterizes the effectiveness of converting exhaust energy into turbine mechanical work. In some examples, the value of turbine efficiency can range from 0.7 to 0.85.

[0080] The turbine output power is determined by the turbine inlet exhaust flow rate, turbine inlet exhaust temperature, turbine inlet exhaust pressure, and turbine efficiency. Based on the equivalence principle of turbine output power and compressor input power, the target turbine inlet pressure to meet the target power requirement can be derived from the target turbine inlet exhaust flow rate, target turbine inlet exhaust temperature, and turbine efficiency. The calculation formula is as follows:

[0081] (7)

[0082] in, For turbine efficiency; The target exhaust flow rate is the exhaust gas flow rate before the vortex. =1.33; =1.4; =286 J / (kg·K); Indicates the target turbine inlet exhaust pressure. Indicates the exhaust temperature at the target vortex inlet; = +0.002 ~ 0.005MPa; For atmospheric pressure and Atmospheric temperature; To represent the target intake airflow; ; =287 J / (kg·K); The target intake pressure.

[0083] According to the embodiments of this application, the target turbine inlet exhaust pressure is back-calculated through the power matching relationship. This ensures that the target turbine inlet exhaust pressure can meet the target power requirements and also conforms to the actual working characteristics of the turbocharger. It avoids the blind calculation of exhaust pressure and solves the problem in the prior art that the exhaust pressure estimation deviation leads to the mismatch between the turbocharger output power and the intake demand, which in turn affects the compensation accuracy of the electric turbocharger.

[0084] According to embodiments of this application, determining the target performance indicators of the electric supercharger based on the target in-turbo exhaust index may include: performing simulation calculations of the engine combustion process based on the fuel injection quantity and actual equivalence ratio of the engine under target transient operating conditions to determine the actual in-turbo exhaust index of the exhaust gas emitted by the engine before reaching the turbocharger; determining the target pressure ratio and target flow rate of the compressor of the electric supercharger based on the target in-turbo exhaust pressure and target in-turbo flow rate in the target in-turbo exhaust index, and based on the actual in-turbo exhaust pressure and actual in-turbo flow rate in the actual in-turbo exhaust index; and determining the target matching power of the motor of the electric supercharger based on the target required power and the transient output power of the turbocharger determined based on the actual in-turbo exhaust index.

[0085] For example, the fuel injection quantity and actual equivalence ratio of the engine under the target transient operating condition can be obtained. The actual equivalence ratio is the ratio of the air-fuel ratio of the engine in actual combustion during the simulation process. Then, the actual fuel injection quantity and actual equivalence ratio are input into the engine combustion simulation model to simulate the actual combustion process of the engine. Finally, the actual turbine exhaust index of the exhaust gas emitted by the engine to the turbocharger is output. The actual turbine exhaust index corresponds to the target turbine exhaust index, including the actual turbine exhaust pressure, the actual turbine exhaust flow rate, and the actual turbine exhaust temperature.

[0086] The difference between the target turbine inlet exhaust flow rate and the actual turbine inlet exhaust flow rate represents the air flow gap that the electric supercharger compressor needs to fill. The difference between the target turbine inlet exhaust pressure and the actual turbine inlet exhaust pressure represents the pressure gap that the electric supercharger compressor needs to fill. Finally, based on the compressor's operating principle (compressor pressure ratio = outlet pressure / inlet pressure, compressor flow rate is the amount of air output per unit time), these flow gaps and pressure gaps are converted into target performance indicators for the electric supercharger compressor.

[0087] Based on the actual turbine inlet exhaust pressure, actual turbine inlet exhaust flow rate, and actual turbine inlet exhaust temperature, combined with turbine efficiency, the transient output power of the turbocharger is calculated using the turbine output power calculation formula. Subsequently, the difference between the target required power and the turbine transient output power represents the power gap that the electric supercharger needs to compensate for, serving as the initial target matching power. Based on the initial target matching power and the estimated efficiency of the electric supercharger, the target matching power is determined.

[0088] The estimated efficiency of an electric supercharger can be the efficiency of the electric supercharger when the operating point is in the high-efficiency range. For example, the estimated efficiency can be 70% to 80% of the efficiency range.

[0089] According to the embodiments of this application, the actual turbine exhaust parameters of the engine are obtained through simulation. By comparing the target and actual exhaust parameters, the flow rate, pressure, and power compensation gap of the electric supercharger are accurately defined. Combining the compressor working principle and power matching logic, the target pressure ratio, target flow rate, and target matching power of the electric supercharger compressor are derived. This achieves the accurate determination of the target performance indicators of the electric supercharger, ensuring that the electric supercharger can accurately compensate for the transient intake deficiency of the turbocharger and avoid energy waste caused by power redundancy. This provides reliable and quantifiable parameter support for the subsequent selection of target electric superchargers.

[0090] Figure 3 A flowchart of an electric supercharger matching method according to an embodiment of this application is shown.

[0091] like Figure 3 As shown, the method includes operations S310 to S350.

[0092] In operation S310, based on the first boundary condition of the injection quantity and the second boundary condition of the predetermined equivalence ratio, the combination of multiple injection quantities and predetermined equivalence ratios of the engine under the target transient operating condition is determined.

[0093] In operation S320, based on multiple sets of fuel injection quantities and predetermined equivalence ratios, the target power range of the electric supercharger motor, the target pressure range of the electric supercharger compressor, and the target flow range are determined.

[0094] In operation S330, multiple candidate electric superchargers are identified based on the target power range, target pressure ratio range, and target flow range of the electric supercharger.

[0095] During the operation of S340, under the target transient condition, the intake compensation simulation was performed on multiple candidate electric superchargers to determine the boosting efficiency of each candidate electric supercharger.

[0096] In operation of S350, the target electric supercharger is determined based on the overall efficiency of multiple candidate electric superchargers.

[0097] The first boundary condition can be the range of injection quantities determined by appropriately increasing the injection quantity for the target transient operating condition after interpolating the steady-state injection quantity MAP. The second boundary condition can be determined to meet the requirements of combustion stability and soot emissions; for example, the second boundary adjustment can be not lower than the critical equivalence ratio of 0.8.

[0098] For example, based on the fuel injection quantity and predetermined equivalence ratio in each combination, the target intake parameters and target power demand of the engine under the corresponding combination can be determined. Simulation calculations can then be used to obtain the target turbine inlet exhaust indices (turbine inlet exhaust temperature, target turbine inlet exhaust flow rate, and target turbine inlet exhaust pressure) for that combination. Based on these target turbine inlet exhaust indices, the target performance indices of the electric supercharger for each combination (motor target power, compressor target pressure ratio, and compressor target flow rate) can be derived. After all combinations have completed the above calculations, the target performance indices of the electric supercharger for all combinations are summarized. The maximum and minimum values ​​of the motor target power are extracted and defined as the target power range of the electric supercharger motor; the maximum and minimum values ​​of the compressor target pressure ratio are extracted and defined as the target pressure ratio range of the compressor; and the maximum and minimum values ​​of the compressor target flow rate are extracted and defined as the target flow rate range of the compressor.

[0099] For example, when determining candidate electric superchargers, the rated power of the electric supercharger's motor must fall within the target power range (or be slightly higher than the upper limit of the range by up to 10%, with a certain redundancy to cope with transient peak demand), the rated pressure ratio of the compressor must cover the target pressure ratio range, and the rated flow rate of the compressor must cover the target flow rate range. At the same time, the installation size, compatibility, and cost of the electric supercharger are taken into account to avoid selecting products that are incompatible with the engine installation space or have excessively high costs.

[0100] Multiple candidate electric superchargers were connected to the simulation model for intake compensation simulation. During the simulation, the operating parameters (actual motor power, actual compressor pressure ratio, and actual flow rate) of each candidate electric supercharger were recorded, and the overall boosting efficiency of each candidate electric supercharger was calculated. The overall boosting efficiency can be the combined efficiency of motor efficiency, compressor efficiency, and transmission efficiency. The motor and compressor combination with the highest overall boosting efficiency was selected first.

[0101] The selection of an electric supercharger system can also be determined by comparing the power, speed, power consumption, performance and economy of different selection options.

[0102] When the power of the electric supercharger is too high, the corresponding speed is higher, the supercharger has a stronger boosting capacity, the intake volume increases, and the equivalence ratio decreases excessively. At this time, although the peak value of the equivalence ratio meets the critical value requirement, the energy consumption of the electric supercharger is too high. Therefore, a third boundary condition for the target matching power can be set so that the target power range is not higher than the third boundary condition.

[0103] According to an embodiment of this application, after determining the target electric supercharger, the method may further include: performing simulated intake compensation simulation on the target electric supercharger under multiple transient operating conditions of constant speed sudden loading, and determining the target operating power of the target electric supercharger under each of the multiple transient operating conditions; and determining the transient operating strategy of the target electric supercharger based on the target operating power of the target electric supercharger under each of the multiple transient operating conditions.

[0104] Multiple transient operating conditions can be, for example, operating conditions with different loading rates and different load peaks within 1 second, such as 0%→70%, 0%→80%, and 0%→90% at a speed of 950 r / min.

[0105] Simulation software can be used to simulate the actual operating state of the target electric supercharger under different transient conditions, and obtain various efficiency parameters in real time. Based on these efficiency parameters, power adaptation parameters for different transient conditions can be determined. For example, the electric supercharger operates at rated power under high load conditions and at optimal efficiency power under medium and low load conditions, ensuring that the electric supercharger can efficiently and accurately perform its intake compensation function under various transient conditions.

[0106] According to the embodiments of this application, candidate electric superchargers are screened by combining multiple sets of operating conditions, and the optimal target electric supercharger is determined by simulation verification. At the same time, a transient operation strategy for the electric supercharger is formulated, which takes into account both the efficiency of the electric supercharger itself and the overall performance of the engine. This effectively improves the combustion stability of the engine under transient operating conditions, reduces fuel consumption and emissions, and enhances the transient response speed and operational reliability of the engine.

[0107] Figure 4 A block diagram of a matching device for an electric supercharger under transient engine conditions, according to an embodiment of this application, is shown.

[0108] The first determining module 410 is used to determine the target intake air flow rate, target intake air pressure, and target required power to compress the air at the initial intake pressure to the target intake air pressure based on the fuel injection quantity and predetermined equivalence ratio of the engine under the target transient operating condition of constant speed sudden loading. The initial intake air pressure is the initial ambient pressure at the inlet of the engine intake manifold.

[0109] The second determining module 420 is used to perform simulation calculations of the engine combustion process based on the fuel injection quantity and a predetermined equivalence ratio, and to determine the target pre-turbo exhaust index of the exhaust gas emitted by the engine before it reaches the turbocharger.

[0110] The third determining module 430 is used to determine the target performance indicators of the electric supercharger based on the target turbine exhaust index. The target performance indicators include the power index of the electric supercharger motor, the pressure ratio index of the electric supercharger compressor, and the flow rate index.

[0111] The fourth determination module 440 is used to determine the target electric supercharger based on the target performance indicators of the electric supercharger.

[0112] It should be noted that the matching device part of the electric supercharger under transient engine conditions in this application corresponds to the matching method part of the electric supercharger under transient engine conditions. For a detailed description of the matching device part, please refer to the matching method part, which will not be repeated here.

[0113] According to embodiments of this application, this application also provides an electronic device, a readable storage medium, and a computer program product.

[0114] According to an embodiment of this application, an electronic device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the method described above.

[0115] According to an embodiment of this application, a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to cause a computer to perform the method described above.

[0116] According to an embodiment of this application, a computer program product includes a computer program that, when executed by a processor, implements the method described above.

[0117] Figure 5 A schematic block diagram is shown of an electronic device 500 suitable for implementing an electric supercharger matching method, which can be used to carry out embodiments of this application.

[0118] Electronic devices are intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic devices can also represent various forms of mobile devices, such as personal digital processors, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely illustrative and are not intended to limit the implementation of the present application described and / or claimed herein.

[0119] like Figure 5 As shown, device 500 includes a computing unit 501, which can perform various appropriate actions and processes based on a computer program stored in read-only memory (ROM) 502 or a computer program loaded from storage unit 508 into random access memory (RAM) 503. RAM 503 may also store various programs and data required for the operation of device 500. The computing unit 501, ROM 502, and RAM 503 are interconnected via bus 504. Input / output (I / O) interface 505 is also connected to bus 504.

[0120] Multiple components in device 500 are connected to input / output (I / O) interface 505, including: input unit 506, such as a keyboard, mouse, etc.; output unit 507, such as various types of displays, speakers, etc.; storage unit 508, such as a disk, optical disk, etc.; and communication unit 509, such as a network card, modem, wireless transceiver, etc. Communication unit 509 allows device 500 to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunications networks.

[0121] The computing unit 501 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 501 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various special-purpose artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 501 performs the various methods and processes described above. For example, in some embodiments, the matching method for the electric supercharger under engine transient conditions can be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as storage unit 508. In some embodiments, part or all of the computer program can be loaded and / or installed on device 500 via ROM 502 and / or communication unit 509. When the computer program is loaded into RAM 503 and executed by the computing unit 501, one or more steps of the matching method for the electric supercharger under engine transient conditions described above can be performed. Alternatively, in other embodiments, the computing unit 501 may be configured by any other suitable means (e.g., by means of firmware) to perform a matching method for the electric supercharger under transient engine conditions.

[0122] Various embodiments of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SoCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments may include implementations in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which may be a dedicated or general-purpose programmable processor, capable of receiving data and instructions from a storage system, at least one input device, and at least one output device, and transmitting data and instructions to the storage system, the at least one input device, and the at least one output device.

[0123] The program code used to implement the methods of this application may be written in any combination of one or more programming languages. This program code may be provided to a processor or controller of a general-purpose computer, special-purpose computer, or other programmable data processing device, such that when executed by the processor or controller, the functions / operations specified in the flowcharts and / or block diagrams are implemented. The program code may be executed entirely on a machine, partially on a machine, as a standalone software package partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0124] In the context of this application, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. Machine-readable media can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fibers, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0125] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for displaying information to the user (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor); and a keyboard and pointing device (e.g., a mouse or trackball) through which the user provides input to the computer. Other types of devices can also be used to provide interaction with the user; for example, feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including sound input, voice input, or tactile input).

[0126] The systems and technologies described herein can be implemented in computing systems that include backend components (e.g., as a data server), or computing systems that include middleware components (e.g., an application server), or computing systems that include frontend components (e.g., a user computer with a graphical user interface or web browser through which a user can interact with implementations of the systems and technologies described herein), or any combination of such backend, middleware, or frontend components. The components of the system can be interconnected via digital data communication of any form or medium (e.g., a communication network). Examples of communication networks include local area networks (LANs), wide area networks (WANs), and the Internet.

[0127] Computer systems can include clients and servers. Clients and servers are generally located far apart and typically interact via communication networks. Client-server relationships are created by computer programs running on the respective computers and having a client-server relationship with each other. Servers can be cloud servers, distributed system servers, or servers incorporating blockchain technology.

[0128] Those skilled in the art will understand that the features described in the various embodiments and / or claims of this application can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in this application. In particular, the features described in the various embodiments and / or claims of this application can be combined and / or combined in various ways without departing from the spirit and teachings of this application. All such combinations and / or combinations fall within the scope of this application.

[0129] The embodiments of this application have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of this application. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. The scope of this application is defined by the appended claims and their equivalents. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of this application, and all such substitutions and modifications should fall within the scope of this application.

Claims

1. A matching method for an electric supercharger under transient engine operating conditions, characterized in that, The electric supercharger is used to compensate for insufficient intake air in the case of insufficient intake air in the original turbocharger of the engine under transient operating conditions. The matching method includes: Based on the fuel injection quantity and predetermined equivalence ratio of the engine under the target transient operating condition of constant speed sudden loading, the target intake air flow rate, target intake air pressure, and target required power to compress the air at the initial intake air pressure to the target intake air pressure are determined. The initial intake air pressure is the initial ambient pressure at the inlet of the engine intake manifold. Based on the fuel injection quantity and the predetermined equivalence ratio, the engine combustion process is simulated and calculated to determine the target in-turbo exhaust index of the exhaust gas emitted by the engine before reaching the turbocharger. Based on the target turbine exhaust index, the target performance index of the electric supercharger is determined. The target performance index includes the target power index of the motor of the electric supercharger, the target pressure ratio index of the compressor of the electric supercharger, and the target flow rate index. The target electric supercharger is determined based on the target performance indicators of the electric supercharger.

2. The matching method according to claim 1, characterized in that, The target turbocharger pre-exhaust index includes the target turbocharger pre-exhaust temperature. Based on the fuel injection quantity and the predetermined equivalence ratio, simulation calculations of the engine combustion process are performed to determine the target turbocharger pre-exhaust index of the exhaust gas emitted by the engine before reaching the turbocharger, including: Based on the fuel injection quantity and the predetermined equivalence ratio, the engine combustion process is simulated to determine the proportion of fuel energy entering the exhaust gas. Based on the fuel energy ratio and the temperature rise per unit fuel energy, the steady-state temperature rise under steady-state operating conditions is determined. Based on the initial temperature rise, the final temperature rise, and the time constant characterizing the exhaust manifold preheating delay, a temperature rise correction amount that decays exponentially with time is constructed. The initial temperature rise is the engine's idle or no-load steady-state exhaust temperature rise before the start of the transient condition, and the final temperature rise is the engine's exhaust temperature rise at the target load steady state after the end of the transient condition. The target turbine inlet exhaust temperature is determined based on the steady-state temperature increase, the temperature increase correction, and the engine intake temperature.

3. The matching method according to claim 2, characterized in that, The target turbocharger pre-exhaust index also includes the target turbocharger pre-exhaust flow rate and the target turbocharger pre-exhaust pressure. Based on the fuel injection quantity and the predetermined equivalence ratio, simulation calculations of the engine combustion process are performed to determine the target turbocharger pre-exhaust index of the exhaust gas emitted by the engine before reaching the turbocharger, including: The target in-flight exhaust flow rate of the engine is determined based on the target intake flow rate and a predetermined conversion coefficient characterizing the engine's intake and exhaust volumes. Based on the target turbine inlet exhaust flow rate, the target turbine inlet exhaust temperature, and the turbine efficiency, the target turbine inlet exhaust pressure that meets the target power requirement is calculated by using the matching relationship between the output power of the turbine in the turbocharger and the input power of the compressor in the turbocharger.

4. The matching method according to any one of claims 1 to 3, characterized in that, The determination of the target performance indicators of the electric supercharger based on the target pre-turbo exhaust index includes: Based on the fuel injection quantity and actual equivalence ratio of the engine under the target transient operating condition, the simulation calculation of the engine combustion process is performed to determine the actual turbine inlet exhaust index of the exhaust gas emitted by the engine before reaching the turbocharger. Based on the target vortex inlet exhaust pressure and target vortex inlet flow rate in the target vortex inlet exhaust index, and based on the actual vortex inlet exhaust pressure and actual vortex inlet flow rate in the actual vortex inlet exhaust index, the target pressure ratio index and target flow rate index of the compressor of the electric supercharger are determined. The target matching power of the electric supercharger motor is determined based on the target required power and the transient output power of the turbocharger determined based on the actual turbocharger exhaust index.

5. The matching method according to claim 4, characterized in that, Based on the target power requirement and the transient output power of the turbocharger determined based on actual pre-turbo exhaust parameters, the target matching power of the electric supercharger's motor is determined, including: The initial target matching power is determined based on the difference between the target power requirement and the transient output power of the turbocharger; The target matching power is determined based on the initial target matching power and the estimated efficiency of the electric supercharger.

6. The matching method according to any one of claims 1 to 3, characterized in that, The method further includes: Based on the first boundary condition of the fuel injection quantity and the second boundary condition of the predetermined equivalence ratio, the combination of multiple sets of fuel injection quantities and predetermined equivalence ratios of the engine under the target transient operating condition is determined; Based on multiple sets of fuel injection quantities and predetermined equivalence ratios, several target turbine inlet exhaust parameters are determined, thereby defining the target power range of the electric supercharger's motor, the target pressure range of the electric supercharger's compressor, and the target flow range. Based on the target power range, target pressure ratio range, and target flow range of the electric supercharger, multiple candidate electric superchargers are determined. Under the target transient operating condition, simulated intake compensation was performed on multiple candidate electric turbochargers to determine the boost efficiency of each candidate electric turbocharger. The target electric supercharger is determined based on the overall efficiency of each of the multiple candidate electric superchargers.

7. The method according to claim 1, characterized in that, The method includes: Under multiple transient operating conditions of constant speed sudden loading, the target electric supercharger is simulated with intake compensation to determine the target operating power of the target electric supercharger under each of the multiple transient operating conditions. Based on the target operating power of the target electric supercharger under multiple transient operating conditions, the transient operating strategy of the target electric supercharger is determined.

8. The method according to claim 1, characterized in that, Based on the fuel injection quantity and predetermined equivalence ratio of the engine under the target transient operating condition of constant speed sudden loading, the target intake air flow rate required by the engine is determined, including: The target intake air flow rate is determined based on the engine's effective power and effective fuel consumption rate determined by the fuel injection quantity, the excess air coefficient corresponding to the predetermined equivalence ratio, and the scavenging coefficient.

9. The method according to claim 8, characterized in that, Based on the fuel injection quantity and predetermined equivalence ratio of the engine under the target transient operating condition of constant speed sudden loading, the target intake pressure required by the engine is determined, including: The engine's average effective pressure is determined based on the fuel injection quantity, the effective fuel consumption rate, the excess air coefficient, the cylinder charge coefficient, and the intake air temperature; the initial intake pressure is then determined. The target intake pressure is determined based on the initial intake pressure and the preset pressure correction amount.

10. A matching device for an electric supercharger under transient engine operating conditions, characterized in that, The electric supercharger is used to compensate for insufficient intake air in the event of insufficient intake air in the original turbocharger of the engine under transient operating conditions. The matching device includes: The first determining module is used to determine the target intake air flow rate, target intake air pressure, and target required power to compress the air at the initial intake air pressure to the target intake air pressure based on the fuel injection quantity and predetermined equivalence ratio of the engine under the target transient operating condition of constant speed sudden loading. The initial intake air pressure is the initial ambient pressure at the inlet of the engine intake manifold. The second determining module is used to perform simulation calculations of the engine combustion process based on the fuel injection quantity and the predetermined equivalence ratio, and to determine the target pre-turbo exhaust index of the exhaust gas emitted by the engine before it reaches the turbocharger. The third determining module is used to determine the target performance index of the electric supercharger based on the target pre-vortex exhaust index. The target performance index includes the power index of the motor of the electric supercharger, the pressure ratio index and the flow rate index of the compressor of the electric supercharger. The fourth determining module is used to determine the target electric supercharger based on the target performance indicators of the electric supercharger.

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