An engine control method and device based on reducing power request

Abstract

The application discloses an engine control method based on power request reduction, and steps are as follows: vehicle acceleration request trigger condition; optimizing engine request air path torque M AirReq : based on engine original request air path torque M AirReqRaw , combined with engine speed n, throttle opening degree pct, throttle opening degree change rate dpct, required time t Delay of fresh air entering the cylinder via the throttle, determining engine request air path torque M AirReq ; determining the final engine request air path torque: arbitrating the air path torque requested by the driver throttle with other torque requests to obtain the final engine request air path torque, controlling the engine intake density based on the final engine request air path torque, reducing the engine actual air path torque, and reducing the demand of the engine power request. The application further discloses an engine control device based on power request reduction. The application can quickly respond to the demand of the engine power request reduction, improve the response capability when the power request is reduced, and can be widely applied to the field of engine control.

Description

Technical Field

[0001] This invention relates to the field of engine control, and in particular to an engine control method and apparatus based on reducing power demand. Background Technology

[0002] Vehicle power and drivability are among the most important performance development indicators. When the engine power demand is reduced, the vehicle needs to respond to the torque reduction demand as soon as possible. However, since there is a certain distance between the throttle valve and the cylinder in the engine intake system, there is a certain delay in the fresh air entering the cylinder from the throttle valve.

[0003] In light of this, a manufacturer has filed an invention patent application with application number CN202211355696.0, entitled "A Pedal Control Method, Device, Equipment, and Vehicle." This patent discloses a method for obtaining the target pedal torque when the target pedal position change rate does not meet a preset change rate, and obtaining a first change rate of the target pedal torque based on the target pedal torque. Then, the first change rate is converted into a second change rate within a change rate threshold, where the second change rate is less than the first change rate, and the target pedal torque is output based on the second change rate. After a preset time has elapsed since the second change rate was used to output the target pedal torque, the target pedal torque continues to be output based on the first change rate. This application controls the first change rate of the target pedal torque within a certain range within a certain time, thereby avoiding rapid torque changes that could endanger the driver or passengers, and giving the driver sufficient reaction time to deal with potential dangers. However, this invention delays the request for the target pedal torque when the pedal change rate is too rapid, limiting the power request of the pedal torque, and does not consider improving acceleration performance from the perspective of vehicle dynamics.

[0004] Consequently, related companies filed another patent application, CN202110067714.4, entitled "A Method, Device, Vehicle, and Storage Medium for Determining Torque Reduction." This patent includes: determining the torque reduction coefficient and the engine's target speed corresponding to the current upshift process; determining the target torque reduction of the engine in the current upshift process based on the engine's moment of inertia, torque reduction coefficient, and target speed; and sending the target torque reduction to the engine controller so that the engine controller adjusts the engine speed in the current upshift process according to the target torque reduction, wherein the difference between the adjusted engine speed and the target speed meets preset conditions. However, similarly, it does not propose improving the torque reduction request performance from the perspective of optimizing the engine's target air volume torque from the engine's internal control perspective.

[0005] In order to quickly respond to the acceleration power demand of the vehicle and improve the power response capability, an engine control method and device based on reducing power demand is proposed. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide an engine control method and apparatus based on reducing power demand, so that it can quickly respond to the reduced engine power demand and improve the response capability when the power demand is reduced.

[0007] This invention provides an engine control method based on reducing power request, comprising the following steps: reducing power request triggering conditions, including conditions such as first engine closed-loop control, first engine operating state, first engine coolant temperature range, first brake pedal not depressed, first exhaust system heating demand, first fuel cut-off request not triggered, and first engine request airflow torque change rate; optimizing the engine request airflow torque M. Air Req Based on the obtained original engine request air path torque M Air ReqRaw Based on this, and combined with engine speed n, throttle opening pct, throttle opening change rate dpct, and the time t required for fresh air to enter the cylinder through the throttle valve, the following parameters are considered. Delay Determine the engine's requested airflow torque M Air Req This is used as the air path torque for the driver's throttle request; the final engine requested air path torque is determined by arbitrating the air path torque for the driver's throttle request with other torque requests. Based on the final engine requested air path torque, the engine intake air density is controlled to reduce the engine air volume, thereby reducing the actual engine air path torque and thus reducing the engine power request requirement.

[0008] In the above technical solution, the conditions for the step of reducing the power request trigger condition are as follows: First engine closed-loop control: the engine is not performing speed closed-loop control; First engine operating state: the engine is in operating state; First engine coolant temperature range: the engine coolant temperature is within the first preset range; First brake pedal not depressed: the brake pedal is not depressed; First exhaust system heating requirement: the engine does not perform exhaust system heating requirement; First fuel cut-off request not triggered: the engine does not trigger fuel cut-off request; First engine requested air path torque change rate: before optimization, the engine requested air path torque change rate is less than the first preset value; all of the above conditions are met.

[0009] In the above technical solution, the optimized engine requests the airflow torque M Air Req The specific steps are as follows: Throttle full open mode: When the throttle is in full open mode, it is necessary to reduce the engine's requested air torque more quickly: M Air Req (N)=M Air Req (N-1)-k×k C ×[M Air ReqRaw (N)-M Air Req (N-1)], Throttle not fully open mode: When the throttle is in the not fully open mode: M Air Req(N)=M Air Req (N-1)-k×[M Air ReqRaw (N)-M Air Req [(N-1)], where M Air ReqRaw == f(n, pct + dpct × t) Delay That is, pct + dpct × t Delay For "throttle opening at which the engine requests airflow torque"; M Air Req (N) represents the engine's requested airflow torque during the Nth sampling period; M Air Req (N-1) represents the engine's requested airflow torque during the (N-1)th sampling period; M Air ReqRaw M is the engine's original request for air circuit torque. Air ReqRaw (N) represents the engine's original requested airflow torque M during the Nth sampling period. Air ReqRaw ;k C is a constant filter coefficient; k is the air path filter coefficient.

[0010] In the above technical solution, the method for obtaining the throttle opening change rate dpct in the steps of throttle full opening mode or throttle non-full opening mode is as follows:

[0011] in,

[0012] dpct(N) is the rate of change of throttle opening in the Nth sampling period, dpct(N-1) is the rate of change of throttle opening in the (N-1)th sampling period, pct(N) is the throttle opening in the Nth sampling period, pct(N-1) is the throttle opening in the (N-1)th sampling period, N is a positive integer, pct(0) occurs when all conditions are met; dpct(0) occurs when all conditions are met, Δt is the sampling period, t c The time constant is used; the value of the air path filtering coefficient k is determined as follows:

[0013] k = f(n.rho) × k(pct,r) AirTrq ReqRatio )×k(dpct,d 2 pct)×k(r Sprk ,r SprkRatio )×(1+r Adapt )

[0014] That is, the air path filter coefficient k is determined by engine speed n, load rho, throttle opening pct, throttle opening change rate dpct, and the second derivative of throttle opening d. 2 pct, current ignition efficiency r Sprk Current ignition angle efficiency r Sprk The ratio of efficiency to minimum ignition angle r SprkRatioThe ratio r of the unoptimized engine requested airflow torque to the engine minimum airflow torque. AirTrq ReqRatio Learning correction factor r Adapt A joint decision.

[0015] In the above technical solution, the specific process for determining the air path filtering coefficient k is as follows: Basic value of air path filtering coefficient k: f(n.rho), determined by engine speed n and load rho, is the basic value of air path filtering coefficient k. The calibration basis is that, after the above conditions are met, the difference between the actual engine torque and the requested engine torque does not exceed 2%, and the difference between the requested engine torque and the actual engine torque is not less than 5%. First correction factor for air path filtering coefficient k: After f(n.rho) is calibrated, based on the throttle opening change rate dpct and the second derivative of the throttle opening d... 2 pct determines k(dpct,d) 2 pct) is the first correction factor for the air path filter coefficient k. The calibration is based on the condition that, after meeting the above conditions, the difference between the actual engine torque and the requested engine torque does not exceed 2%, and the difference between the requested engine torque and the actual engine torque is not less than 5%. The second correction factor for the air path filter coefficient k is: after completing the above calibration, based on the throttle opening pct and the air path torque ratio r... AirTrq ReqRatio Determine k(pct,r) AirTrq ReqRatio The second correction factor for the air path filter coefficient k is calibrated based on the condition that the optimized engine air path torque is not lower than the engine minimum torque, but is not limited by the engine minimum torque; the third correction factor for the air path filter coefficient k is: after completing the above calibration, based on the current ignition efficiency r Sprk And the ratio of ignition efficiency r SprkRatio Determine k(r) Sprk ,r SprkRatio ) is the third correction factor of the air path filter coefficient k. The calibration basis is that after the above conditions are met, the difference between the actual engine fire path torque and the engine requested fire path torque shall not exceed 2%, and the difference between the engine requested fire path torque and the engine actual fire path torque shall not be less than 5%.

[0016] In the above technical solution, in the steps of throttle full-open mode or throttle non-full-open mode, the learning correction factor r Adapt The determination process is as follows: Learning trigger conditions include: second engine closed-loop control, second engine operating status, second engine coolant temperature range, second brake pedal not depressed, second exhaust system heating requirement, second fuel cut-off request not triggered, second engine request for air circuit torque change rate, and conditions for updating the vehicle mileage preset value; all of the above conditions must be met; learning correction factor r. Adapt Learning conditions: throttle opening, throttle opening change rate, and ignition efficiency r Sprk air circuit torque ratio rAirTrq ReqRatio And the ratio of ignition efficiency r SprkRatio Divide the data into several intervals, including the intervals of throttle opening, the intervals of throttle opening change rate, and the ignition efficiency r. Sprk air circuit torque ratio r AirTrq ReqRatio And the ratio of ignition efficiency r SprkRatio Each interval is combined to form multiple learning correction factors r Adapt Corresponding learning conditions; learning correction factor r Adapt Update processing: Based on the distribution range of the difference between the engine's requested firing torque and the engine's actual firing torque in the learning operating conditions, a correction factor r is learned for each of the four operating conditions. Adapt The learning update only updates one type of function; under other operating conditions, the learning correction factor r is adjusted. Adapt The update remains unchanged; the learning correction factor r is used. Adapt Immediately after the update, the records of the difference between the engine's actual firing torque and the engine's requested firing torque for all operating conditions are updated. That is, the difference between the engine's actual firing torque and the engine's requested firing torque for any operating condition under all operating conditions is re-evaluated. Initially, it is assumed that there is no difference between the engine's actual firing torque and the engine's requested firing torque. After the next learning conditions are met, each operating condition is re-evaluated.

[0017] In the above technical solution, the learning correction factor r Adapt The specific process of learning the operating conditions is as follows: Throttle opening range: Divide the throttle opening into A ranges; Throttle opening change rate range: Divide the throttle opening change rate into B ranges; Ignition efficiency r Sprk Range: Ignition efficiency r Sprk Divided into C intervals; air path torque ratio r AirTrq ReqRatio Range: The air circuit torque ratio r AirTrq ReqRatio Divided into D intervals; ignition efficiency ratio r SprkRatio Range: the ignition efficiency ratio r SprkRatio Divide into E intervals; determine the intervals that form A*B*C = F combinations as F learning correction factors r. Adapt In learning scenario one, the intervals that form A*B*C*D*E = G combinations are defined as G learning correction factors r. Adapt Learning and working conditions two.

[0018] In the above technical solution, the learning correction factor r Adapt The specific operation process for the four working conditions in the update processing steps is as follows: 1) F learning correction factors r Adapt In all learning conditions, the difference between the engine's requested firing torque and the engine's actual firing torque exceeded 8%. Therefore, 11) if G learning correction factors r AdaptIf, in learning condition two, the difference between the engine's requested firing torque and the actual firing torque exceeds 8%, then the next vehicle driving cycle begins, and the learning correction factor r is applied. Adapt 12) If condition 11) is not met, the next vehicle driving cycle begins, and the learning correction factor r is increased by 1 time. Adapt Updated to m² times the original value; 2) F learning correction factors r Adapt In the first learning condition, if the difference between the engine's requested firing torque and the engine's actual firing torque does not exceed 8% but exceeds 5%, then 21) if G learning correction factors r Adapt In learning condition two, if the difference between the engine's requested firing torque and the actual firing torque exceeds 5% but does not exceed 8%, then the next vehicle driving cycle begins, and the learning correction factor r is applied. Adapt Update to m3 times the original value; 22) If condition 21) is not met, the next vehicle driving cycle begins, and the learning correction factor r is used. Adapt Updated to m4 times the original value; 3) F learning correction factors r Adapt In the first learning condition, if the difference between the actual engine firing torque and the requested engine firing torque exceeds 2% but does not exceed 5%, then 31) if G learning correction factors r Adapt In learning condition two, if the difference between the actual engine torque and the requested engine torque exceeds 2% but does not exceed 5%, then the next vehicle driving cycle begins, and the learning correction factor r is applied. Adapt Update to m5 times the original value; 32) If condition 31) is not met, the next vehicle driving cycle begins, and the learning correction factor r is adjusted. Adapt Updated to m / 6 times the original value; 4) F learning correction factors r Adapt In all learning conditions, the difference between the actual engine firing torque and the requested engine firing torque exceeded 5%. Therefore, 41) if G learning correction factors r Adapt If, in learning condition two, the difference between the actual engine firing torque and the requested engine firing torque exceeds 5%, then the next vehicle driving cycle begins, and the learning correction factor r is applied. Adapt Update to m7 times the original value; 42) If condition 41) is not met, the next vehicle driving cycle begins, and the learning correction factor r is adjusted. Adapt Updated to 8 times the size of the previous version.

[0019] The above technical solution also includes a step to terminate the transition of engine request gas path torque. That is, after adopting engine optimization control to reduce power request, the controlled engine request gas path torque is gradually transitioned to the engine request gas path torque without optimization control according to two situations. The specific process is as follows: 1) When the engine control conditions for reducing power request after optimization control are not met simultaneously, and the engine does not trigger a fuel cut-off request, the engine request gas path torque is gradually restored to the engine request gas path torque without optimization control at a first preset change rate k1. The first preset change rate k1 is jointly determined by the engine speed and the current ignition efficiency. The calibration basis is: the engine speed fluctuation does not exceed ±20 rpm, and the actual ignition torque fluctuation does not exceed ±5%. 2) When the engine control conditions for reducing power request after optimization control are not met simultaneously, and the engine triggers a fuel cut-off request, the engine request gas path torque is gradually restored to the engine request gas path torque without optimization control at a second preset change rate k2. The second preset change rate k2 is determined by the engine speed. The calibration basis is: the engine speed fluctuation does not exceed ±20 rpm, and the NOx emission is minimal.

[0020] The present invention also provides an engine control device based on reduced power request, having a computer program that can execute an engine control method based on reduced power request.

[0021] The present invention is based on an engine control method and apparatus for reducing power demand, which has the following beneficial effects: optimizing the engine demand air path torque to improve the intake control time delay caused by fresh air entering the cylinder through the throttle valve, and continuously learning and updating the engine demand air path torque throughout the engine life cycle, which can improve torque response accuracy not only in the development stage, but also throughout the entire vehicle life cycle. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall process of the engine control method based on reducing power demand according to the present invention;

[0023] Figure 2 This refers to step two of the engine control method based on reducing power demand in the present invention: optimizing the engine's requested airflow torque M. Air Req A flowchart illustrating the process of determining the air path filter coefficient k value;

[0024] Figure 3 This refers to step two of the engine control method based on reducing power demand in the present invention: optimizing the engine's requested airflow torque M. Air Req Learning correction factor r Adapt A flowchart illustrating the process;

[0025] Figure 4This is a flowchart illustrating step four, the transition step of terminating the engine request air path torque, in the engine control method based on reducing power request of the present invention.

[0026] Figure 5 This is a schematic diagram of the engine control device based on reducing power demand according to the present invention. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, but these embodiments should not be construed as limiting the present invention.

[0028] The purpose of this invention is to provide an engine control method and apparatus based on reducing power demand.

[0029] Invention patent application CN202210303455.5, entitled "Method, Apparatus, Device, and Readable Storage Medium for Calculating Gas Flow Response Time," proposes the time required for fresh air to enter the cylinder via the throttle valve. Based on the engine torque request, the required fresh air intake volume to enter the cylinder is obtained. Since this fresh air intake volume ultimately enters through the throttle valve, there is a certain delay in the fresh air's journey from the throttle valve to the cylinder, resulting in a delay in the engine torque request. To improve the response capability when the engine power request is reduced, the required time t for fresh air to enter the cylinder via the throttle valve is calculated. Delay Control optimizations are implemented to improve vehicle power and reduce demand.

[0030] By default, engine torque control for reducing power request employs existing known techniques. However, this invention's engine control method for reducing power request includes employing an optimized engine control method for reducing power request, and then gradually transitioning to the engine's requested airflow torque without optimized control after the optimized control method is discontinued.

[0031] See Figure 1 The present invention is based on an engine control method for reducing power demand, comprising the following steps:

[0032] Step 1: Reduce the power request triggering conditions: This includes the conditions for the first engine closed-loop control, the first engine operating status, the first engine coolant temperature range, the first brake pedal not being pressed, the first exhaust system heating requirement, the first fuel cut-off request not being triggered, and the first engine requesting the rate of change of airflow torque. The specific process of this step is as follows:

[0033] An engine control method that reduces the engine power demand after optimization is adopted when the following conditions are met simultaneously:

[0034] 1. The engine is not under closed-loop speed control; if the engine is under closed-loop speed control, its torque must not be disturbed to avoid affecting the accuracy of the closed-loop speed control.

[0035] 2. The engine is running;

[0036] 3. The engine coolant temperature is within the preset range, which in this embodiment refers to a coolant temperature between 60℃ and 100℃. If the coolant temperature is too low, the engine needs to warm up to improve fuel economy and emissions, resulting in relatively weak power performance; if the coolant temperature is too high, the engine is prone to knocking, etc. In order to protect the engine, it is necessary to limit the engine's power demand.

[0037] 4. The brake pedal is not depressed, i.e., the accelerator pedal opening is 0%;

[0038] 5. The engine does not require exhaust system heating; the specific requirements for exhaust system acceleration are detailed in patent CN202110184814.5 "Ignition Efficiency Control Method Based on Engine Exhaust System Heating Requirements";

[0039] 6. The engine did not trigger a fuel cut-off request;

[0040] 7. The change rate of engine requested air path torque before optimization (the engine requested air path torque before optimization refers to the engine requested torque before optimization by this invention; the change rate of engine requested air path torque refers to the engine requested air path torque in the current sampling period minus the engine requested air path torque in the previous sampling period divided by the sampling period; the sampling period in this embodiment is 10ms) is less than the preset value, which is -15Nm / 10ms in this embodiment.

[0041] After all the above conditions are met

[0042] The engine's requested firing torque M is determined based on engine speed n and throttle opening pct. Sprk Req M Sprk Req =f(n,pct), this part is calibrated based on the vehicle's drivability requirements, and must meet both subjective drivability requirements and performance requirements after the engine power demand is reduced. This part is a conventional technology.

[0043] Step 2: Optimize engine request for airflow torque M Air Req Based on the obtained original engine request air path torque M Air ReqRaw Based on this, and combined with engine speed n, throttle opening pct, throttle opening change rate dpct, and the time t required for fresh air to enter the cylinder through the throttle valve, the following parameters are considered. Delay Determine the engine's requested airflow torque M Air Req This is then used as the air circuit torque for the driver's throttle request. The specific process of this step is as follows:

[0044] To improve the intake control time delay caused by fresh air entering the cylinder through the throttle valve, the engine control is optimized. This optimization can be achieved by optimizing the engine's requested air path torque, which is then used as the air path torque requested by the driver's throttle.

[0045] The following details the calculated and optimized engine requested airflow torque:

[0046] Based on engine speed n, throttle opening pct, throttle opening change rate dpct, and the time t required for fresh air to enter the cylinder through the throttle valve. Delay Determine the engine's requested airflow torque M Air Req .

[0047] 1. When the throttle is in fully open mode (throttle control mode can be found in patent CN202010074677.5 "Control System and Method for Electronic Throttle of Exhaust Gas Turbocharged Engine"), in order to ensure that there is no throttling effect in fully open mode and to achieve a reduction in power as quickly as possible, the torque requested by the engine from the intake circuit needs to be reduced more quickly when the throttle is fully open:

[0048] M Air Req (N)=M Air Req (N-1)-k×k C ×[M Air ReqRaw (N)-M Air Req (N-1)];

[0049] 2. When the throttle is in a non-fully open mode (throttle control mode can be found in patent CN202010074677.5 "Control System and Method for Electronic Throttle of Exhaust Gas Turbocharged Engine"):

[0050] M Air Req (N)=M Air Req (N-1)-k×[M Air ReqRaw (N)-M Air Req (N-1)];

[0051] Among them, M Air ReqRaw == f(n, pct + dpct × t) Delay ), which is about pct+dpct×t Delay Set to "Throttle opening at which the engine requests airflow torque", where M Air ReqRaw The f function and the engine request fire torque M SprkReq The f function uses the same algorithm; M Air Req (N) represents the engine's requested airflow torque during the Nth sampling period; M Air Req (N-1) represents the engine's requested airflow torque during the (N-1)th sampling period; M Air ReqRawM is the engine's original request for air circuit torque. Air ReqRaw (N) represents the engine's original requested airflow torque M during the Nth sampling period. Air ReqRaw ;k C is a constant filter coefficient, which is 1.05 in this embodiment; k is the air path filter coefficient.

[0052] To avoid small fluctuations in throttle opening controlled by the driver and to prevent poor stability of the control system, the throttle opening change rate (dpct) is optimized. The method for obtaining the throttle opening change rate (dpct) is as follows:

[0053]

[0054] Where dpct(N) is the rate of change of throttle opening in the Nth sampling period, dpct(N-1) is the rate of change of throttle opening in the (N-1)th sampling period, pct(N) is the throttle opening in the Nth sampling period, pct(N-1) is the throttle opening in the (N-1)th sampling period, and N is a positive integer of 1, 2, 3, ...; the time when pct(0) occurs is the moment when all the above conditions are just met, and in this embodiment, pct(0) is taken as 0%; the time when dpct(0) occurs is the moment when all the above conditions are just met, and in this embodiment, Δpct(0) is taken as 0% / s, Δt is the sampling period, and in this embodiment, it is taken as 10ms, t c The time constant is 40ms in this embodiment.

[0055] See Figure 2 The air path filter coefficient k is determined as follows:

[0056] k = f(n.rho) × k(pct,r) AirTrq ReqRatio )×k(dpct,d 2 pct)×k(r Sprk ,r SprkRatio )×(1+r Adapt )

[0057] That is, the air path filter coefficient k is determined by engine speed n, load rho (actual intake air density entering the cylinder), throttle opening pct, throttle opening change rate dpct, and the second derivative of throttle opening d. 2 pct(second derivative of throttle opening d) 2 PCT is obtained based on the throttle opening change rate dpct, and the method of obtaining it is the same as the calculation method of the throttle opening change rate dpct, with a corresponding time constant of 40ms and the current ignition efficiency r. Sprk Current ignition angle efficiency r Sprk The ratio of efficiency to minimum ignition angle r SprkRatio(The current ignition angle efficiency is the current actual ignition angle efficiency, while the minimum ignition angle efficiency is the ignition efficiency corresponding to the minimum ignition angle allowed under the current operating conditions. The minimum ignition angle efficiency is defined the same as the minimum ignition efficiency, as detailed in patent CN202210676269.6 "A method for controlling the minimum ignition efficiency of a gasoline engine". Finally, the ratio of the current ignition angle efficiency to the minimum ignition angle efficiency is referred to as the ignition efficiency ratio r.) SprkRatio The ratio r of the unoptimized engine requested air path torque (referring to the engine requested air path torque obtained without the optimization control of this invention, which is the original air path torque) to the engine minimum torque. AirTrq ReqRatio (The definition of minimum air path torque for an engine is found in patent CN202210540148.9, "Turbocharged Engine Air Path Torque Control Method". The ratio of the engine's requested air path torque to the engine's minimum air path torque is referred to as the air path torque ratio r.) AirTrq ReqRatio Learning correction factor r Adapt Jointly determined. Among them, the learning correction factor r Adapt It will be stored after power-off, with a default value of 0. The specific learning method will be described later.

[0058] The following section details the methods for determining the various parameters of the gas path filter coefficient k, including the learning of the correction factor r during the determination process. Adapt If the value is 0, it will not be updated during the calibration of other parameters, but will be updated through self-learning at different stages of the vehicle's lifecycle after SOP.

[0059] 1) f(n.rho), determined by engine speed n and load rho, is the basic value of the air path filter coefficient k. Under different engine speeds and loads, the throttle opening pct is 60%, the throttle opening change rate dpct is -50% / s, and the second derivative of the throttle opening d 2 pct is 0% / s 2 Current ignition efficiency r Sprk The ignition efficiency ratio is 0.5, r SprkRatio The ratio is 3, and the air circuit torque ratio r is... AirTrq ReqRatio The calibration results are obtained from calibration 4. The calibration basis is that, after meeting the above conditions, the difference between the engine's actual firing torque and the engine's requested firing torque should not exceed 2% (to ensure fuel economy), and at the same time, the difference between the engine's requested firing torque and the engine's actual firing torque should not be less than 5%. See Table 1 below for details:

[0060] Table 1

[0061]

[0062]

[0063] 2) After f(n.rho) is calibrated, based on the rate of change of throttle opening dpct and the second derivative of throttle opening d2 pct determines k(dpct,d) 2 pct) is the first correction factor for the gas path filter coefficient k, which is applied when the throttle opening pct is 60% and the current ignition efficiency r Sprk The ignition efficiency ratio is 0.5, r SprkRatio The ratio is 3, and the air circuit torque ratio r is... AirTrq ReqRatio To determine the different rates of change of throttle opening dpct and the second derivative of throttle opening d under the condition of 4, 2 The larger the absolute value of the rate of change of throttle opening and the smaller the second derivative of the throttle opening, the larger the filter coefficient k. This results in a faster reduction in the engine's requested airflow torque, leading to a faster decrease in the target airflow volume and a better response to changes in throttle opening. However, an excessively large filter coefficient k can cause excessive airflow fluctuations, affecting torque control overshoot. The calibration is based on the condition that, after meeting the above conditions, the difference between the engine's actual firing torque and the engine's requested firing torque does not exceed 2% (to ensure fuel economy), and the difference between the engine's requested firing torque and the engine's actual firing torque is not less than 5%. See Table 2 below for details.

[0064] Table 2

[0065]

[0066]

[0067] The throttle opening change rate is 0% / s. The optimized engine requires a specific airflow torque M. Air Req Similar to the unoptimized engine's requested airflow torque, calculations based on the previous formula show that no optimization was performed. However, the purpose of the filter coefficient in the table above when the throttle opening change rate is 0% / s is to interpolate the throttle opening change rate from 0% / s to -20% / s, ensuring that the calibration requirements are met even at throttle opening change rates greater than -20% / s.

[0068] 3) After the above calibration is completed, based on the throttle opening pct and the air circuit torque ratio r AirTrq ReqRatio Determine k(pct,r) AirTrq ReqRatio ) is the second correction factor for the air path filter coefficient k, which is used when the throttle opening change rate dpct is -50% / s and the second derivative of the throttle opening d 2 pct is 0% / s 2 Current ignition efficiency r Sprk The ignition efficiency ratio is 0.5, r SprkR a tio To determine the throttle opening (pct) and air circuit torque ratio (r) for different 3-stage throttle openings. AirTrq ReqRatio The effect of the throttle opening being smaller, but with a higher air-to-gas torque ratio r... AirTrq ReqRatioThe smaller the value, the less capable the engine airflow torque is of optimization. Therefore, the smaller the filter coefficient k is. Its calibration is based on the condition that the optimized engine airflow torque is not lower than the engine's minimum airflow torque, but is not limited by the engine's minimum airflow torque. See Table 3 below for details:

[0069] Table 3

[0070]

[0071]

[0072] 4) After the above calibration is completed, based on the current ignition efficiency r Sprk And the ratio of ignition efficiency r SprkRatio Determine k(r) Sprk ,r SprkRatio ) is the third correction factor for the air path filter coefficient k, which is applied when the throttle opening pct is 60%, the throttle opening change rate dpct is -50% / s, and the second derivative of the throttle opening d 2 pct is 0% / s 2 air circuit torque ratio r AirTrq ReqRatio To determine the different throttle openings (pct) and air circuit torque ratios (r) for the four steps, AirTrq ReqRatio The impact of the current ignition efficiency r. Sprk The smaller the ignition efficiency ratio r SprkRatio The smaller the value, the larger the filter coefficient k. In this case, the ignition angle adjustment capability is too small, and the optimization of the air circuit torque needs to be increased. The calibration basis is that after the above conditions are met, the difference between the engine's actual air circuit torque and the engine's requested air circuit torque should not exceed 2% (to ensure fuel economy), and at the same time, the difference between the engine's requested air circuit torque and the engine's actual air circuit torque should not be less than 5%. See Table 4 below for details:

[0073] Table 4

[0074]

[0075]

[0076] See Figure 3 The following section details the learning correction factor r. Adapt The learning method includes the following learning trigger conditions:

[0077] 1) The engine is not under closed-loop speed control; if the engine is under closed-loop speed control, its torque must not be disturbed to avoid affecting the accuracy of the closed-loop speed control.

[0078] 2) The engine is running;

[0079] 3) The engine coolant temperature is within the preset range, which in this embodiment refers to a coolant temperature between 60℃ and 100℃. If the coolant temperature is too low, the engine needs to warm up to improve fuel economy and emissions, resulting in relatively weak power performance; if the coolant temperature is too high, the engine is prone to knocking, etc. In order to protect the engine, it is necessary to limit the engine's power demand.

[0080] 4) The brake pedal is not depressed, i.e., the accelerator pedal opening is 0%;

[0081] 5) The engine does not perform the requirement of exhaust system heating; the specific exhaust system acceleration requirement is described in patent CN202110184814.5 "Ignition efficiency control method based on engine exhaust system heating requirement";

[0082] 6) The engine did not trigger a fuel cut-off request;

[0083] 7) The change rate of engine requested air path torque before optimization (engine requested air path torque before optimization refers to the engine requested torque before optimization by this patent; the change rate of engine requested air path torque refers to the engine requested air path torque in the current sampling period minus the engine requested air path torque in the previous sampling period divided by the sampling period; the sampling period in this embodiment is 10ms) exceeds the preset value, and in this embodiment it is taken as -15Nm / 10ms.

[0084] 8) Learning correction factor r Adapt If the vehicle mileage that has not been updated exceeds a preset value, this embodiment sets it at 5 kilometers to avoid excessively frequent learning.

[0085] After all the above conditions are met, proceed to learning the correction factor r. Adapt Learning process of working conditions;

[0086] Learning correction factor r Adapt Learning conditions: throttle opening, throttle opening change rate, and ignition efficiency r Sprk air circuit torque ratio r AirTrq ReqRatio And the ratio of ignition efficiency r SprkRatio Divide the data into several intervals, including the intervals of throttle opening, the intervals of throttle opening change rate, and the ignition efficiency r. Sprk air circuit torque ratio r AirTrq ReqRatio And the ratio of ignition efficiency r SprkRatio Each interval is combined to form multiple learning correction factors r Adapt Corresponding learning conditions;

[0087] 1) Divide the throttle opening into 4 intervals: 0 ≤ pct ≤ 20%, 20% < pct ≤ 60%, 60% < pct ≤ 80%, and 80% < pct ≤ 100%.

[0088] 2) Divide the throttle opening change rate into 5 intervals: -500% / s < pct ≤ -200% / s, -200% / s < dpct ≤ -100% / s, -100% / s < dpct ≤ -50% / s, -50% / s < dpct ≤ -20% / s, and -20% / s ≤ dpct ≤ 0.

[0089] 3) Improve ignition efficiency r Sprk Five intervals satisfying 0.1≤r Sprk ≤0.3, 0.3<r Sprk ≤0.5, 0.5<r Sprk ≤0.7, 0.7<r Sprk ≤0.9, 0.9<r Sprk ≤1,

[0090] 4) Adjust the air circuit torque ratio r AirTrq ReqRatio The three intervals 1≤r satisfy the condition AirTrq ReqRatio ≤2,2<r AirTrq ReqRatio ≤4, 4<r AirTrq ReqRatio ≤6;

[0091] 5) Adjust the ignition efficiency ratio r SprkRatio Six intervals satisfying 1≤r SprkRatio ≤2,2<r SprkRatio ≤3, 3<r SprkRatio ≤4, 4<r SprkRatio ≤5, 5<r SprkRatio ≤6, 6<r SprkRatio ≤8

[0092] 6) The intervals that form 4*5*5=100 combinations are defined as 100 learning correction factors r. Adapt The learning condition, which consists of the first, second, and third working conditions, is defined as the correction factor r. Adapt Learning working condition one, which has 4*5*5=100 combinations; the working conditions that make up the 1st, 2nd, 3rd, 4th, and 5th working conditions are determined as the correction factor r. Adapt Learning Working Condition 2, which has a total of 4*5*5*3*6=1800 combinations of working conditions;

[0093] If the following occurs, then proceed to learning the correction factor r. Adapt Update process:

[0094] 1) 100 learning correction factors r Adapt In all learning conditions, the difference between the engine's requested firing torque and the engine's actual firing torque exceeded 8%. Therefore, 11) if there are 1800 learning correction factors r... AdaptIn the second learning cycle, if the difference between the engine's requested firing torque and the actual firing torque exceeds 8%, the next vehicle driving cycle begins, and the correction factor r is adjusted. Adapt Update to 1.2 times the original value; 12) If condition 11) is not met, the next vehicle driving cycle begins, and the learning correction factor r is adjusted. Adapt Updated to 1.15 times the original size;

[0095] 2) 100 learning correction factors rA dapt In the first learning condition, if the difference between the engine's requested firing torque and the engine's actual firing torque does not exceed 8% but exceeds 5%, then 21) if there are 1800 learning correction factors r Adapt In learning condition two, if the difference between the engine's requested firing torque and the actual firing torque exceeds 5% but does not exceed 8%, then the next vehicle driving cycle begins, and the learning correction factor r is applied. Adapt Update to 1.12 times the original value; 22) If condition 21) is not met, the next vehicle driving cycle begins, and the learning correction factor r is adjusted. Adapt Updated to 1.1 times the original value;

[0096] 3) 100 learning correction factors r Adapt In all learning conditions, the difference between the actual engine firing torque and the requested engine firing torque exceeded 2% but did not exceed 5%. Therefore, 31) if there are 1800 learning correction factors r... Adapt In learning condition two, if the difference between the actual engine torque and the requested engine torque exceeds 2% but does not exceed 5%, then the next vehicle driving cycle begins, and the learning correction factor r is applied. Adapt Update to 0.9 times the original value; 32) If condition 31) is not met, the next vehicle driving cycle begins, and the learning correction factor r is adjusted. Adapt Updated to 0.95 times the original value;

[0097] 4) 100 learning correction factors r Adapt In all learning conditions, the difference between the actual engine firing torque and the requested engine firing torque exceeded 5%. Therefore, 41) if there are 1800 learning correction factors r... Adapt If, in learning condition two, the difference between the actual engine firing torque and the requested engine firing torque exceeds 5%, then the next vehicle driving cycle begins, and the learning correction factor r is applied. Adapt Update to 0.8 times the original value; 42) If condition 41) is not met, the next vehicle driving cycle begins, and the learning correction factor r is adjusted. Adapt Updated to 0.85 times the original value;

[0098] In the above four learning scenarios, the learning correction factor r is...Adapt When updating learning, only one type is updated, and the priority of the above types decreases progressively.

[0099] Under other operating conditions, the learning correction factor r Adapt The update remains unchanged.

[0100] In learning the correction factor r Adapt Immediately after the update, the records of the difference between the engine's actual firing torque and the engine's requested firing torque for 100 learning conditions one and 1800 learning conditions two will be updated. That is, the difference between the engine's actual firing torque and the engine's requested firing torque for any condition under 100 learning conditions one and 1800 learning conditions two will be re-evaluated. Initially, it is assumed that there is no difference between the engine's actual firing torque and the engine's requested firing torque. After the next learning conditions are met, each condition will be re-evaluated.

[0101] Step 3: Determine the final engine airflow torque request: Arbitrate the airflow torque requested by the driver's throttle with other torque requests to obtain the final engine airflow torque request. Based on the final engine airflow torque request, control the engine intake air density to reduce the engine air volume, thereby reducing the actual engine airflow torque and thus reducing the engine power demand. The specific process of this step is as follows:

[0102] Arbitrate the airflow torque requested by the driver's throttle with other torque requests (such as ESC, cruise control, etc.) to obtain the final engine airflow torque request. Based on the final engine airflow torque request, control the engine intake air density to reduce the engine air volume and thus reduce the engine's actual airflow torque. After the engine's actual airflow torque is reduced, the engine's firing torque capability will also be reduced (because the maximum value of the engine's actual firing torque does not exceed the engine airflow torque), thereby reducing the engine's power demand.

[0103] See Figure 4 Step four: Terminating the transition of engine requested air path torque. That is, after adopting engine optimization control with reduced power request, the controlled engine requested air path torque is gradually transitioned to the engine requested air path torque without optimization control, depending on two scenarios. The specific process is as follows:

[0104] 1. When the engine control conditions for reducing power request after optimized control are not simultaneously met, and the engine does not trigger a fuel cut-off request, the engine's requested air circuit torque gradually recovers to the engine's requested air circuit torque before optimized control at a first preset change rate k1 (the maximum absolute value of the change rate does not exceed the first preset change rate k1). The first preset change rate k1 is jointly determined by the engine speed and the current ignition efficiency to avoid engine speed fluctuations and ignition torque fluctuations during the transition recovery process. The calibration basis in this embodiment is: engine speed fluctuation (the difference between two adjacent speeds, with the time interval Δt being a sampling period of 10ms) does not exceed ±20rpm, and the actual ignition torque fluctuation (the ignition torque in the current sampling period minus the ignition torque in the previous sampling period divided by the ignition torque in the current sampling period, with the time interval Δt being a sampling period of 10ms) does not exceed ±5%. See Table 5 below for details:

[0105] Table 5

[0106]

[0107] 2. When the engine control conditions for reducing power demand after optimized control are not simultaneously met, and the engine triggers a fuel cut-off request, the engine's requested airflow torque gradually recovers to the engine's requested airflow torque before optimized control using a second preset change rate k2. The second preset change rate k2 is determined by the engine speed to avoid engine speed fluctuations during the transition recovery process, while simultaneously reducing NOx emissions. The calibration basis for this embodiment is: in the emission test, the engine speed fluctuation (the difference between two adjacent speeds, with the time interval Δt being a sampling period of 10ms) does not exceed ±20rpm, and NOx emissions are minimized. See Table 6 below for details:

[0108] Table 6

[0109]

[0110] The above describes the method for controlling the engine's requested airflow torque, ultimately limiting the engine's requested airflow torque to within the engine's minimum torque range. Based on the engine's requested airflow torque, the intake volume is controlled to improve power performance.

[0111] See Figure 5 The present invention is based on an engine control device for reducing power demand, comprising the following parts:

[0112] The power request trigger condition reduction module includes the following conditions: first engine closed-loop control, first engine operating status, first engine coolant temperature range, first brake pedal not depressed, first exhaust system heating demand, first fuel cut-off request not triggered, and first engine request for air circuit torque change rate.

[0113] Optimize engine request for airflow torque M Air Req Module: Based on the acquired engine raw request air path torque M Air ReqRaw Based on this, and combined with engine speed n, throttle opening pct, throttle opening change rate dpct, and the time t required for fresh air to enter the cylinder through the throttle valve, the following parameters are considered. Delay Determine the engine's requested airflow torque M Air Req And use it as the air circuit torque for the driver's throttle request;

[0114] The final engine request air path torque module arbitrates the air path torque requested by the driver's throttle along with other torque requests to obtain the final engine request air path torque. Based on the final engine request air path torque, the engine intake air density is controlled to reduce the engine air volume, thereby reducing the actual engine air path torque and thus reducing the engine power request requirement.

[0115] Termination of Engine Requested Airway Torque Transition Module: After adopting engine optimization control with reduced power request, the well-controlled engine requested airway torque is gradually transitioned to the engine requested airway torque without optimization control, depending on two scenarios.

[0116] The technical principles and key points of this invention are as follows:

[0117] The key points of the vehicle acceleration engine control method in this application are:

[0118] Engine requests an airflow torque optimization algorithm;

[0119] Method for determining the filter coefficient for engine request airflow path torque optimization;

[0120] Engine request air path torque optimization filter coefficient learning factor learning method.

[0121] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

[0122] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. An engine control method based on reducing power demand, characterized in that: Includes the following steps: The conditions for reducing the power request triggering condition include: first engine closed-loop control, first engine operating state, first engine coolant temperature range, first brake pedal not depressed, first exhaust system heating requirement, first fuel cut-off request not triggered, and first engine request for change rate of air circuit torque. The conditions for the step of reducing the power request triggering condition are as follows: First engine closed-loop control: The engine speed is not under closed-loop control; First engine operating status: The engine is running; Engine coolant temperature range: The engine coolant temperature is within the first preset range; First, the brake pedal was not pressed: The brake pedal was not pressed; First exhaust system heating requirement: The engine does not require exhaust system heating; First fuel cut-off request not triggered: The engine did not trigger a fuel cut-off request; First engine requested air path torque change rate: Before optimization, the engine requested air path torque change rate was less than the first preset value; All of the above conditions must be met; Optimize engine request for airflow torque Based on the obtained engine's original requested airflow torque Based on this, combined with engine speed Throttle opening Throttle opening change rate Based on the time required for fresh air to enter the cylinder through the throttle valve. Determine the engine's requested airflow torque And use it as the air circuit torque for the driver's throttle request; Determine the final engine requested air path torque: Arbitrate the air path torque requested by the driver's throttle along with other torque requests to obtain the final engine requested air path torque. Based on the final engine requested air path torque, control the engine intake air density to reduce the engine air volume, thereby reducing the actual engine air path torque and thus meeting the requirement of reducing the engine power request.

2. The engine control method based on reduced power request according to claim 1, characterized in that: The optimized engine requests airflow torque The specific steps are as follows: Throttle Full Open Mode: When the throttle is in full open mode, the engine needs to reduce the requested air torque more quickly. ， Throttle not fully open mode: When the throttle is in the not fully open mode: ， in, ,Right now This refers to the throttle opening at which the engine requests torque from the air passage. Request the air path torque for the engine in the Nth sampling period; Request the air path torque for the engine in the (N-1)th sampling period; The engine's original requested airflow torque, The original request for the engine's airflow torque in the Nth sampling period ; The filter coefficients are constants. This represents the air path filtering coefficient.

3. The engine control method based on reduced power request according to claim 2, characterized in that: In the steps of the fully open throttle mode or the partially open throttle mode, the rate of change of throttle opening... The method to obtain it is as follows: ， in, Let N be the rate of change of throttle opening during the Nth sampling period. The throttle opening change rate during the (N-1)th sampling period. For the throttle opening in the Nth sampling period, The throttle opening is the value in the (N-1)th sampling period, where N is a positive integer. It occurs when all conditions are met. It occurs when all conditions are met. The sampling period is It is a time constant; The air path filtering coefficient The value is determined as follows: That is, the air path filter coefficient k is determined by the engine speed. ,load Throttle opening Throttle opening change rate Second-order differential of throttle opening Current ignition efficiency Current ignition angle efficiency Ratio of efficiency to minimum ignition angle The ratio of unoptimized engine requested airflow torque to engine minimum airflow torque. Learning correction factor A joint decision.

4. The engine control method based on reduced power request according to claim 3, characterized in that: The air path filtering coefficient The specific process for determining the value is as follows: The basic value of the air path filter coefficient k is determined by the engine speed. and load Definite It is the basic value of the air path filter coefficient k. The calibration basis is that after the above conditions are met, the difference between the actual engine firing torque and the engine requested firing torque does not exceed 2%, and the difference between the engine requested firing torque and the engine actual firing torque is not less than 5%. First correction factor for air path filter coefficient k: After calibration, based on the rate of change of throttle opening and the second derivative of throttle opening Sure It is the first correction factor for the air path filter coefficient k. The calibration basis is that after the above conditions are met, the difference between the actual engine firing torque and the engine requested firing torque does not exceed 2%, and the difference between the engine requested firing torque and the engine actual firing torque is not less than 5%. Second correction factor for air path filter coefficient k: After completing the above calibration, based on throttle opening And air circuit torque ratio Sure It is the second correction factor of the air path filtering coefficient k. The calibration basis is that the optimized engine air path torque is not lower than the engine minimum torque, but is not limited by the engine minimum torque. The third correction factor for the gas path filter coefficient k: After completing the above calibration, based on the current ignition efficiency and ignition efficiency ratio Sure It is the third correction factor of the air path filter coefficient k. The calibration basis is that after the above conditions are met, the difference between the actual engine fire path torque and the engine requested fire path torque shall not exceed 2%, and the difference between the engine requested fire path torque and the engine actual fire path torque shall not be less than 5%.

5. The engine control method based on reduced power request according to claim 4, characterized in that: In the steps of the fully open throttle mode or the partially open throttle mode, the learning correction factor The determination process is as follows: Learning trigger conditions include: second engine closed-loop control, second engine operating status, second engine coolant temperature range, second brake pedal not depressed, second exhaust system heating demand, second fuel cut-off request not triggered, second engine request for air circuit torque change rate, and conditions for updating vehicle mileage preset value; the second engine closed-loop control is when the engine is not performing speed closed-loop control; if the engine is performing speed closed-loop control, its torque is not allowed to be disturbed to avoid affecting the accuracy of speed closed-loop control. All of the above conditions must be met; Learning correction factor Learning conditions: throttle opening, throttle opening change rate, and ignition efficiency. Air circuit torque ratio and ignition efficiency ratio Divide the data into several intervals, including the intervals for throttle opening, the intervals for the rate of change of throttle opening, and the ignition efficiency. Air circuit torque ratio and ignition efficiency ratio Each interval is combined to form multiple learning correction factors. Corresponding learning conditions; Learning correction factor Update processing: Based on the distribution range of the difference between the engine's requested firing torque and the engine's actual firing torque in the learning operating conditions, a correction factor is learned for each of the four operating conditions. The learning update only updates one type of function; under other operating conditions, the learning correction factor is adjusted. The update remains unchanged; Learning correction factors Immediately after the update, the records of the difference between the engine's actual firing torque and the engine's requested firing torque for all operating conditions are updated. That is, the difference between the engine's actual firing torque and the engine's requested firing torque for any operating condition under all operating conditions is re-evaluated. Initially, it is assumed that there is no difference between the engine's actual firing torque and the engine's requested firing torque. After the next learning conditions are met, each operating condition is re-evaluated.

6. The engine control method based on reduced power request according to claim 5, characterized in that: The learning correction factor The specific process for learning operating conditions is as follows: Throttle opening range: Divide the throttle opening into A ranges; Throttle opening change rate range: Divide the throttle opening change rate into B ranges; Ignition efficiency Range: Ignition efficiency Divide into C intervals; air circuit torque ratio Range: The ratio of air circuit torque Divide into D intervals; Ignition efficiency ratio Range: Ignition efficiency ratio Divide into E intervals; The intervals that form A*B*C=F combinations are defined as F learning correction factors. In learning scenario one, the intervals that form A*B*C*D*E=G combinations are defined as G learning correction factors. Learning and working conditions two.

7. The engine control method based on reduced power request according to claim 6, characterized in that: The learning correction factor The specific operation procedures for the four working conditions in the update processing steps are as follows: 1) F learning correction factors In the first learning condition, if the difference between the engine's requested firing torque and the engine's actual firing torque exceeds 8%, then 11) if there are G learning correction factors... In the second learning cycle, if the difference between the engine's requested firing torque and the actual firing torque exceeds 8%, the next driving cycle begins, and the correction factor is learned. 12) If condition 11) is not met, the next vehicle driving cycle begins, and the correction factor is learned. Updated to m2 times the original value; 2) F learning correction factors In the first learning condition, if the difference between the engine's requested firing torque and the engine's actual firing torque does not exceed 8% but exceeds 5%, then 21) if there are G learning correction factors... In the second learning cycle, if the difference between the engine's requested firing torque and the actual firing torque exceeds 5% but does not exceed 8%, then the next vehicle driving cycle begins, and the correction factor is learned. Update to m3 times the original value; 22) If condition 21) is not met, the next vehicle driving cycle begins, and the correction factor is learned. Updated to 4 times the size of the previous version; 3) F learning correction factors In the first learning condition, if the difference between the actual engine firing torque and the requested engine firing torque exceeds 2% but does not exceed 5%, then 31) if there are G learning correction factors In learning condition two, if the difference between the actual engine torque and the requested engine torque exceeds 2% but does not exceed 5%, then the next vehicle driving cycle begins, and the learning correction factor is applied. Update to m5 times the original value; 32) If condition 31) is not met, the next vehicle driving cycle begins, and the correction factor is learned. Updated to 6 times the size of the previous version; 4) F learning correction factors In all learning conditions, the difference between the actual engine firing torque and the requested engine firing torque exceeded 5%. Therefore, 41) if there are G learning correction factors... In the second learning cycle, if the difference between the actual engine torque and the requested engine torque exceeds 5%, the next driving cycle begins, and the correction factor is learned. Update to m7 times the previous value; 42) If condition 41) is not met, the next vehicle driving cycle begins, and the correction factor is learned. Updated to 8 times the size of the previous version.

8. The engine control method based on reduced power request according to claim 7, characterized in that: It also includes a step to terminate the transition of engine requested air path torque. That is, after adopting engine optimization control with reduced power request, the controlled engine requested air path torque is gradually transitioned to the engine requested air path torque without optimization control, depending on two scenarios. The specific process is as follows: 1) When the engine control conditions for reducing power demand after optimized control are not simultaneously met, and the engine does not trigger a fuel cut-off request, the engine's requested air circuit torque will gradually recover to the engine's requested air circuit torque before optimized control by a first preset change rate k1. The first preset change rate k1 is jointly determined by the engine speed and the current ignition efficiency, and is calibrated based on the following: engine speed fluctuation does not exceed ±20 rpm, and actual ignition torque fluctuation does not exceed ±5%. 2) When the engine control conditions for reducing power request after optimization control are not met simultaneously, and the engine triggers a fuel cut-off request, the engine request air path torque will gradually recover to the engine request air path torque without optimization control at the second preset change rate k2. The second preset change rate k2 is determined by the engine speed, and the calibration basis is: the engine speed fluctuation does not exceed ±20 rpm, and the NOx emission is minimal.

9. An engine control device based on reducing power demand, comprising a computer program, characterized in that: The computer program is capable of executing the engine control method based on reduced power request as described in any one of claims 1 to 8.

Images