A method for monitoring engine pressure signal degradation in hybrid vehicles

Abstract

The present invention discloses a method for monitoring engine pressure signal degradation in hybrid vehicles. The method comprises: verifying the throttle inlet pressure signal using a first method and a second method to determine whether the throttle inlet pressure signal is faulty. The first method reads the throttle inlet pressure signal and the post-throttle pressure signal in real time when the throttle pressure verification condition is met, and determines whether the throttle inlet pressure signal is faulty based on a preset time. The second method obtains the average throttle inlet pressure and the average throttle outlet pressure over a preset time when the throttle inlet pressure stable operating condition is met, and determines whether the throttle inlet pressure signal is faulty based on a self-learning correction coefficient. The method provided by the present invention can verify the rationality of the pressure signal of the pre-throttle pressure sensor.

Description

Technical Field

[0001] The present invention relates to the field of engine control technology, and in particular to a method for monitoring engine pressure signal degradation of a hybrid vehicle. Background Art

[0002] The engine is a key power source in hybrid vehicles. Throttle inlet pressure, a crucial parameter for throttle and boost system control, impacts vehicle dynamics, drivability, and fuel economy, making monitoring engine pressure signal degradation particularly important.

[0003] The patent with application number 202110982953.2 discloses "A throttle flow calculation method, device, equipment and readable storage medium". The patent proposes to use the throttle pre-pressure (inlet pressure) and post-pressure (outlet pressure) to estimate the EGR flow, but does not propose a method for monitoring the degradation of the engine pressure signal of a hybrid vehicle.

[0004] The patent with application number 202110518171.3 discloses "A method for measuring EGR mass flow, a measuring device and an exhaust gas treatment system". The patent proposes to use the pre-throttle pressure (inlet pressure) and post-throttle pressure (outlet pressure) to estimate the EGR flow, but does not propose a method for monitoring the degradation of the engine pressure signal of a hybrid vehicle. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for monitoring the degradation of the engine pressure signal of a hybrid vehicle model in response to the deficiencies of the existing technology. The method can verify the rationality of the pressure signal of the pre-throttle pressure sensor.

[0006] To achieve the above objectives, according to one aspect of the present invention, a method for monitoring engine pressure signal degradation in a hybrid vehicle is provided, comprising:

[0007] Using the first method and the second method to check the throttle inlet pressure signal respectively;

[0008] determining whether a fault occurs in the throttle inlet pressure signal according to the results of the first method and the second method;

[0009] The first method is: when the throttle pressure verification condition is met, the throttle inlet pressure signal and the throttle post-pressure signal are read in real time;

[0010] determining whether a fault occurs in the throttle inlet pressure signal according to the throttle inlet pressure signal, the throttle post-pressure signal, and a preset time;

[0011] The second method is: when the throttle inlet pressure stable working condition judgment condition is met, obtaining the average value of the throttle inlet pressure and the average value of the throttle outlet pressure within a preset time;

[0012] Whether a throttle inlet pressure signal fails is determined based on the average throttle inlet pressure, the average throttle outlet pressure, and a self-learning correction coefficient.

[0013] In the above solution, the first method is specifically: when the throttle pressure verification condition is met, the throttle inlet pressure signal p is read in real time. ThrBfAct and the post-throttle pressure signal p ThrAftAct , if it appears: If the continuous occurrence time exceeds the preset time t1, it is determined that the throttle inlet pressure signal has a fault; otherwise, it is determined that the throttle inlet pressure signal has no fault.

[0014] In the above solution, the throttle pressure verification condition is:

[0015] (1) The engine speed does not exceed the preset value for a period of time exceeding the preset time t EngMovingDelay ; wherein the preset value of the engine speed is 30 rpm;

[0016] (2) There is no malfunction in the atmospheric pressure sensor and the throttle body pressure sensor;

[0017] (3) The difference between the atmospheric pressure signal and the throttle valve pressure signal is within a preset range;

[0018] (4) The fluctuations of the atmospheric pressure signal and the post-throttle pressure signal do not exceed the preset range.

[0019] where t EngMovingDelay =t EngMovingDelayRaw ×(1+r Delay ), t EngMovingDelayRaw is the preset time initial value, r Delay The correction coefficient is learned at the preset time. Its initial value is 0, and it is continuously learned and updated. It can be saved after the vehicle is powered off.

[0020] Throttle opening pct when shutting down ThrActOff The closer the throttle valve is to the natural opening (the natural opening refers to the opening of the throttle valve motor that is not controlled, i.e. the default opening when the power is not on), the airflow in the intake system is still flowing, and the longer the delay is before the throttle valve inlet pressure signal is checked. Based on test verification, to ensure the accuracy of the throttle valve inlet pressure signal verification, the preset time initial value t is calibrated. EngMovingDelayRaw and the throttle opening pct ThrActOff The result is shown in the preset time initial value t EngMovingDelayRawand the throttle opening pct ThrActOff Comparison table.

[0021] The preset time initial value t EngMovingDelayRaw Depends on the throttle opening pct when the engine speed does not exceed the preset value ThrActOff , wherein the preset time initial value t EngMovingDelayRaw and the throttle opening pct ThrActOff The comparison table is:

[0022]

[0023] The reason why the above only focuses on the throttle opening between 0% and 9% is that when the engine requests to stop, the throttle is first fully closed and then slowly enters the natural opening to quickly reduce the engine torque and achieve a quick stop. EngMovingDelayRaw The shorter the time, the greater the fluctuation of the throttle inlet pressure is and the more stable the pressure value is when the engine is shut down. If t EngMovingDelayRaw If the time is too long, the pressure signal verification may be detected late, the pressure signal verification efficiency may be low, and the controller may need to be powered for a long time, resulting in power consumption.

[0024] The throttle opening pct ThrActOff The determination is made by adopting a control method for an electronic throttle of an exhaust gas turbocharger engine (for details, refer to Chinese patent publication number CN111255581A), wherein the control method for an electronic throttle of an exhaust gas turbocharger engine is:

[0025] Step 1: Set the throttle full-open exit flag, throttle full-open preparation exit flag, and transient throttle full-open permission flag in the throttle controller;

[0026] The throttle valve fully open exit flag is set to 1 when the difference between the throttle valve intake pressure and the throttle valve target intake pressure is greater than the calibration value A1, and is set to 0 when it is less than the calibration value A2, and A1 is greater than A2;

[0027] The throttle valve fully open ready exit flag is set to 1 when the difference between the estimated throttle valve intake pressure and the estimated throttle valve target intake pressure is greater than the calibration value B1, and is set to 0 when it is less than the calibration value B2, and B1 is greater than B2;

[0028] The transient throttle full-open flag is set to 1 when the difference between the throttle inlet pressure and the throttle outlet pressure is less than the calibration value C1, and is set to 0 when it is greater than the calibration value C2, and C1 is less than C2;

[0029] Step 2: When the throttle fully open exit flag is set to 1, the throttle control mode is the normal throttle control mode. In the normal throttle control mode, the effective area of ​​the throttle is the target throttle effective area A. Eff ;

[0030] Step 3: When the throttle fully open exit flag is set to 0, the throttle control mode at the previous moment is the throttle normal control mode, and when the transient throttle fully open flag is set to 0, the throttle enters the throttle normal control mode;

[0031] Step 4: When the throttle fully open exit flag is set to 0, and the transient throttle fully open flag is set to 1, and the throttle fully open ready exit flag is set to 1, the throttle enters the throttle overshoot prevention control mode. In the throttle overshoot prevention control mode, the effective area of ​​the throttle is the adjusted target throttle effective area min (A Eff1 ,A Eff2 ), and the adjusted target throttle effective area is not less than A Eff , where A Eff1 By A Eff Multiply by the preset compensation coefficient to get, A Eff2 By A Eff Add the preset compensation amount to obtain;

[0032] Step 5: When the throttle fully open exit flag is set to 0, and the transient throttle fully open flag is set to 1, and the throttle fully open ready exit flag is 0, the throttle enters the throttle fully open control mode. In the throttle fully open control mode, the effective area of ​​the throttle is the target throttle fully open effective area A. EffMax , and make the target throttle effective area change rate the maximum change rate allowed by the throttle when the throttle is fully open.

[0033] The throttle opening pct ThrActOff =(A eff '-A0) / (A 100 -A0)×100%; where A eff ' is the final throttle effective area after the throttle valve is processed in different control modes. The minimum throttle opening of 0% and the maximum opening of 100% correspond to the throttle effective area A respectively. 100 and A0.

[0034] In the above solution, the preset time learning correction coefficient r Delay The method to obtain is:

[0035] When the first method is used to determine that the throttle inlet pressure signal is not faulty, the throttle inlet pressure signal is recorded from the time the engine enters a shutdown state and the engine speed does not exceed a preset value, and the throttle inlet pressure signal is filtered: ThrBfActFilter (N) = K ThrBf ×[p ThrBfAct (N)-p ThrBfActFilter (N-1)]+p ThrBfActFilter(N-1); where p ThrBfAct is the throttle inlet pressure, p ThrBfAct (N) is the throttle inlet pressure of the Nth sampling period, p ThrBfActFilter is the throttle inlet pressure after first-order low-pass filtering, p ThrBfActFilter (N) is the filtered throttle inlet pressure of the Nth sampling period, p ThrBfActFilter (N-1) is the filtered throttle inlet pressure of the N-1th sampling period, N = 1, 2, 3..., p ThrBfActFilter (0) is equal to the throttle inlet pressure p at the 0th sampling period ThrBfAct (0); wherein the 0th sampling period is the sampling period for reading the moment when the engine enters the shutdown state and the engine speed does not exceed the preset value, and the sampling period interval is Δt; K ThrBf is the filter coefficient;

[0036] Record the time from when the engine enters the shutdown state and the engine speed does not exceed the preset value to when the engine stops. ThrBfAct (N)-p ThrBfActFilter (N)|>min[p ThrBfAct (N), p ThrBfActFilter (N)]×r ThrBfActLim The shortest time is t0, and the throttle opening pct when the engine enters the shutdown condition and the engine speed does not exceed the preset value is recorded. ThrActOff0 and atmospheric pressure; where r ThrBfActLim is a preset value; the preset time learning correction coefficient r Delay The update method is as follows:

[0037] First case: if the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct at the moment ThrActOff0 When it is greater than 9%, and the last preset time learning correction coefficient r Delay If the difference between the atmospheric pressure corresponding to the update and the current atmospheric pressure exceeds the preset value, only the preset time learning correction coefficient r under the throttle opening of 9% is updated. Delay , the preset time learning correction coefficient r is not updated at other throttle openings. Delay The update calculation formula is: Among them, r Delay (z) is the preset time learning correction coefficient of the last self-learning update, k1 is the weighting coefficient; if the engine enters the shutdown condition and the engine speed does not exceed the preset value, the throttle opening pct at the moment ThrActOff0 When it is greater than 9%, and the last preset time learning correction coefficient r DelayIf the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ;

[0038] Second situation: if the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct at the moment ThrActOff0 The value is one of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%. If the last preset time learning correction coefficient r Delay If the difference between the atmospheric pressure corresponding to the update and the current atmospheric pressure exceeds the preset value, only the preset time learning correction coefficient r under the corresponding throttle opening is updated. Delay , the preset time learning correction coefficient r is not updated at other throttle openings Delay , the preset time learning correction coefficient r Delay The update calculation formula is: Among them, r Delay (z) is the preset time learning correction coefficient of the last self-learning update, k1 is the weighting coefficient; the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ;

[0039] The third case: if the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct at the time ThrActOff0 The value is between two adjacent values ​​of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%. If the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure and the current atmospheric pressure exceeds the preset value during the update, only the preset time learning correction coefficient r of the corresponding throttle opening will be updated. Delay , the preset time learning correction coefficient r is not updated at other throttle openings Delay ; If the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay The method for determining the corresponding throttle opening area is as follows: Assume that if the engine enters the shutdown state and the engine speed does not exceed the preset value at the moment of the throttle opening pct ThrActOff0 The value is between the throttle opening A and B, where A and B are a pair of adjacent values ​​of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%. If the throttle opening A read before this update corresponds to the preset time tEngMovingDelay t A , the preset time t corresponding to the throttle opening B read before this update EngMovingDelay t B , determine the throttle opening pct ThrActOff The corresponding preset time learning correction coefficient r Delay Use r Delay (pct ThrActOff ) means:

[0040] where r Delay (pct ThrActOff )(z) is the throttle opening updated in the last self-learning, which is pct ThrActOff The preset time learning correction coefficient under the setting time, k2 is the weighting coefficient; while updating the preset time learning correction coefficient of the throttle opening A and the throttle opening B, respectively, with r Delay (A) and r Delay (B) means:

[0041]

[0042] Wherein k3 and k4 are both preset weighting coefficients.

[0043] The updated throttle opening pct under shutdown conditions ThrActOff The corresponding preset time learning correction coefficient r Delay According to the throttle opening pct under shutdown conditions ThrActOff Store separately and update the preset time t in the subsequent vehicle driving cycle EngMovingDelay Used to determine the throttle pressure verification condition.

[0044] In the above solution, the second method is specifically:

[0045] When the throttle inlet pressure stable working condition judgment condition is met, obtain the average throttle inlet pressure within the preset time t3 Average throttle outlet pressure

[0046] like It is determined that the throttle valve inlet pressure signal is faulty, otherwise it is determined that the throttle valve inlet pressure signal is not faulty.

[0047] In the above scheme, r Adpt It is a self-learning correction coefficient. The default value is 0. It can be saved when the vehicle is powered off.

[0048] In the above scheme, the self-learning correction coefficient r AdptThe method for obtaining is as follows: record the number of times CNT3 that the throttle inlet pressure stable working condition judgment condition is met, and record the number of times CNT3 that the throttle inlet pressure stable working condition judgment condition is met. The number of times CNT4 is recorded after the throttle inlet pressure stable working condition judgment condition is met The number of times CNT3, CNT4 and CNT5 are updated at most once in each driving cycle of the vehicle;

[0049] If CNT3 ≥ 200, CNT4 ≥ 160, and CNT5 ≤ 10, then r Adpt =r Adpt (z)-0.01;

[0050] If CNT3 ≥ 200, CNT4 ≤ 10, and CNT5 ≥ 130, then r Adpt =r Adpt (z)+0.015;

[0051] In other cases, r Adpt =r Adpt (z);

[0052] where r Adpt (z) is the self-learning correction coefficient of the last update; when CNT3 ≥ 200, then the self-learning correction coefficient r Adpt After the update, CNT3, CNT4 and CNT5 are reset to 0 and the counting starts again when the next condition is met.

[0053] In the above solution, the throttle inlet pressure stable working condition judgment condition is:

[0054] (1) The engine is running;

[0055] (2) The target air intake volume is stable;

[0056] (3) The actual intake pressure at the throttle outlet is stable;

[0057] (4) The engine speed fluctuation does not exceed the preset range;

[0058] (5) The opening of the boost actuator is equal to its full opening;

[0059] (6) The throttle opening is greater than the preset value;

[0060] (7) The throttle outlet pressure signal is not detected as a fault;

[0061] (8) The product of the engine's short-term fuel correction and the long-term fuel correction is within a preset range and exceeds a preset time t2.

[0062] In the above scheme, the method for determining whether the target intake volume is stable is:

[0063] rho DesFilter (N) = K Rho ×[rho DesRaw (N)-rho DesFilter (N-1)]+rho DesFilter (N-1); where rho DesRaw is the target air intake volume, rho DesRaw (N) is the target intake volume of the Nth sampling period, rho DesFilter is the target intake volume after first-order low-pass filtering, rho DesFilter (N) is the filtered target intake volume of the Nth sampling period, rho DesFilter (N-1) is the filtered target intake air volume of the N-1th sampling period, N = 1, 2, 3..., rho DesFilter (0) is equal to the target intake air volume rho at the 0th sampling period DesRaw (0); sampling period interval Δt; K Rho is the coefficient, is the preset value: Where n is the engine speed, k Rho is the air volume filter coefficient, which is the preset value;

[0064] in|rho DesRaw (N)-rho DesFilter (N)| <min[rho DesRaw (N), rho DesFilter (N)]×r RhoLim The condition is continuously met for a period of time up to T Rho The target air intake volume is in a stable state. RhoLim is the preset value, T Rho is the default value.

[0065] In the above scheme, the method for determining whether the actual intake pressure at the throttle outlet is stable is:

[0066] p ManFilter (N) = K Man ×[p Man (N)-p ManFilter (N-1)]+p ManFilter (N-1); where p Man is the throttle outlet intake pressure, p Man (N) is the throttle outlet intake pressure of the Nth sampling period, p ManFilter is the throttle outlet intake pressure after first-order low-pass filtering, p ManFilter (N) is the filtered throttle outlet intake pressure of the Nth sampling period, p ManFilter(N-1) is the filtered throttle outlet intake pressure of the N-1th sampling period, N = 1, 2, 3..., p ManFilter (0) is equal to the throttle outlet intake pressure p at the 0th sampling period Man (0); the sampling period interval Δt is the preset value; K Man is the coefficient, is the preset value: Where n is the engine speed, k Man is the throttle outlet intake pressure filter coefficient, which is the preset value;

[0067] In|p Man (N)-p ManFilter (N)| <min[p Man (N), p ManFilter (N)]×r ManLim The condition is continuously met for a period of time up to T Man The latter indicates that the intake pressure is in a stable state; among them, r ManLim is the preset value, T Man is the default value.

[0068] In the above solution, the method for determining whether the throttle inlet pressure signal is faulty according to the results of the first method and the second method is:

[0069] If during this driving cycle, the second method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT1, and the first method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT2, and CNT1>50, CNT2<2, then it is finally determined that the throttle inlet pressure signal has no fault, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z) +0.03, and clear CNT1 and CNT2 to 0;

[0070] If during this driving cycle, the second method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT1, and the first method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT2, and CNT1<2, CNT2>50, then it is finally determined that the throttle inlet pressure signal fails, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z) -0.04, and clear CNT1 and CNT2 to 0;

[0071] If during this driving cycle, the second method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT1, and the first method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT2, and CNT1>50, CNT2>50, then it is finally determined that the throttle inlet pressure signal fails, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z);

[0072] In other cases, it is finally determined that the throttle inlet pressure signal has no fault, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z);

[0073] where r Adpt (z) is the self-learning correction coefficient of the last update; CNT1 and CNT2 are updated at most once in each driving cycle.

[0074] As mentioned above, only two methods are used to update r. Adpt The reason is that the sampling estimation method of the second method is during the operation of the engine. During the operation of the engine, as the life cycle of the engine goes on, more parts may age, and the data offset caused by aging is greater than that of the first method when the engine is stopped. When the engine is stopped, only static data and the performance of the throttle itself are considered. Based on this, only the second data offset is considered. However, the second method also operates under steady-state engine conditions, and its detection accuracy is relatively high. Therefore, its r Adpt The update speed is not very fast and needs to be updated after multiple failures occur.

[0075] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0076] The present invention provides a method for monitoring engine pressure signal degradation in hybrid vehicles. The method verifies whether the intake pressure is reasonable through multiple methods, and performs pressure signal degradation monitoring strictly and accurately. At the same time, parameters are continuously updated during the pressure signal degradation monitoring process, thereby improving the subsequent pressure signal degradation monitoring and identification accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. Throughout the drawings, the same reference figures denote the same components. In the drawings:

[0078] Figure 1 Schematic diagram of the exhaust gas turbocharger engine intake system in the embodiment of the present invention.

[0079] Figure 2 The figure is a flow chart of a method for monitoring engine pressure signal degradation of a hybrid vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0080] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0081] It should be understood that the size of the serial numbers of the steps in the embodiment does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0082] Example 1

[0083] The main components of the exhaust gas turbocharger engine intake system based on this invention include: atmospheric pressure sensor, supercharger, electronic pressure relief valve, intercooler, throttle pre-temperature and pressure sensor, throttle, throttle post-intake air temperature and pressure sensor, carbon canister solenoid valve, EGR, VVT system, etc. Figure 1 As shown. The atmospheric pressure sensor can read the atmospheric pressure and is installed in the PCB board of the controller ECU; the supercharger includes the supercharger body and the exhaust bypass valve, and the boost pressure is controlled by adjusting the opening of the exhaust bypass valve; the electronic pressure relief valve is used to prevent the air flow from oscillating back and forth in the supercharger compressor when the engine has a torque reduction request, thereby opening the pressure relief valve to improve supercharger surge, thereby increasing engine life and improving NVH; the pre-throttle temperature and pressure sensor can read the temperature and pressure of the supercharged gas before the throttle; the intercooler is a mechanical part, uncontrolled, located between the supercharger compressor and the throttle, cooling the supercharged gas; the intake air temperature and pressure sensor after the throttle can read the temperature and pressure of the supercharged gas before the throttle; the carbon canister solenoid valve is used to introduce fuel vapor into combustion and prevent it from volatilizing into the atmosphere;

[0084] EGR, or exhaust gas recirculation, returns some of the engine's exhaust gas to the intake manifold, where it reenters the cylinder along with the fresh air mixture. VVT adjusts intake (exhaust) volume, valve opening and closing timing, and angle, regulating the amount of air entering the cylinder. The throttle inlet pressure signal verification in this invention verifies the rationality of the pressure signal from the pre-throttle pressure sensor.

[0085] According to one aspect of the present invention, the present invention provides a method for monitoring the degradation of a hybrid vehicle engine pressure signal. Figure 2,include:

[0086] S1, using the first method and the second method to check the throttle inlet pressure signal.

[0087] Specifically, in this embodiment, the first method is: when the throttle pressure verification condition is met, the throttle inlet pressure signal and the throttle post-pressure signal are read in real time;

[0088] According to the throttle inlet pressure signal, the throttle post-pressure signal and the preset time, it is determined whether the throttle inlet pressure signal is faulty.

[0089] The first method is as follows: when the throttle pressure verification condition is met, the throttle inlet pressure signal p is read in real time. ThrBfAct and the post-throttle pressure signal p ThrAftAct , if it appears: If the continuous occurrence time exceeds the preset time t1 (0.5s in this example), it is determined that the throttle inlet pressure signal has a fault; otherwise, it is determined that the throttle inlet pressure signal has no fault.

[0090] In this embodiment, the throttle pressure verification condition is:

[0091] (1) The engine speed does not exceed the preset value (30 rpm in this example) for a period of time exceeding the preset time t EngMovingDelay ;

[0092] where t EngMovingDelay =t EngMovingDelayRaw ×(1+r Delay ), t EngMovingDelayRaw is the preset time initial value, r Delay The correction coefficient is learned at the preset time. Its initial value is 0, and it is continuously learned and updated. It can be saved after the vehicle is powered off.

[0093] Throttle opening pct when shutting down ThrActOff The closer the throttle valve is to the natural opening (the natural opening refers to the opening of the throttle valve motor without control, that is, the default opening when the power is off. In this example, the natural opening of the engine throttle valve is between 7% and 9%), the longer the airflow in the intake system is still flowing, and the longer the delay is before the throttle valve inlet pressure signal is checked. Based on test verification, to ensure the accuracy of the throttle valve inlet pressure signal verification, the preset time initial value t is calibrated. EngMovingDelayRaw and throttle opening pct ThrActOff The result is shown in the preset time initial value t EngMovingDelayRaw and throttle opening pct ThrActOff Comparison table.

[0094] Preset time initial value t EngMovingDelayRawDepends on the throttle opening pct when the engine speed does not exceed the preset value ThrActOff , where the preset time initial value t EngMovingDelayRaw and throttle opening pct ThrActOff The comparison table is:

[0095]

[0096] The reason why the above only focuses on the throttle opening between 0% and 9% is that when the engine requests to stop, the throttle is first fully closed and then slowly enters the natural opening to quickly reduce the engine torque and achieve a quick stop. EngMovingDelayRaw The shorter the time, the greater the fluctuation of the throttle inlet pressure is and the more stable the pressure value is when the engine is shut down. If t EngMovingDelayRaw If the time is too long, the pressure signal verification may be detected late, the pressure signal verification efficiency may be low, and the controller may need to be powered for a long time, resulting in power consumption.

[0097] Throttle opening pct ThrActOff The determination is made by adopting a control method for an electronic throttle of an exhaust gas turbocharged engine (for details, refer to Chinese patent publication number CN111255581A).

[0098] (2) There is no malfunction in the atmospheric pressure sensor and the throttle body pressure sensor;

[0099] (3) The difference between the atmospheric pressure signal and the post-throttle pressure signal is within a preset range, which in this example is ±0.3 kPa;

[0100] (4) The fluctuation of the atmospheric pressure signal and the post-throttle pressure signal does not exceed the preset range, which is ±0.1 kPa in this example.

[0101] In this embodiment, the preset time learning correction coefficient r Delay The method to obtain is:

[0102] When the first method is used to determine that the throttle inlet pressure signal is not faulty, the throttle inlet pressure signal is recorded from the time the engine enters the shutdown state and the engine speed does not exceed the preset value (30 rpm in this example), and the throttle inlet pressure signal is filtered: ThrBfActFilter (N) = K ThrBf ×[p ThrBfAct (N)-p ThrBfActFilter (N-1)]+p ThrBfActFilter (N-1); where p ThrBfAct is the throttle inlet pressure, p ThrBfAct (N) is the throttle inlet pressure of the Nth sampling period, p ThrBfActFilter is the throttle inlet pressure after first-order low-pass filtering, p ThrBfActFilter(N) is the filtered throttle inlet pressure of the Nth sampling period, p ThrBfActFilter (N-1) is the filtered throttle inlet pressure of the N-1th sampling period, N = 1, 2, 3..., p ThrBfActFilter (0) is equal to the throttle inlet pressure p at the 0th sampling period ThrBfAct (0); where the 0th sampling period is the sampling period when the engine enters the shutdown state and the engine speed does not exceed the preset value (30 rpm in this example), and the sampling period interval is Δt, which is 10 ms in this example; K ThrBf is the filter coefficient, which is 0.02 in this example;

[0103] Record the time from when the engine enters the shutdown state and the engine speed does not exceed the preset value (30rpm in this example) to when the |p ThrBfAct (N)-p ThrBfActFilter (N)|>min[p ThrBfAct (N), p ThrBfActFilter (N)]×r ThrBfActLim The shortest time is t0, and the throttle opening pct is recorded when the engine enters the shutdown state and the engine speed does not exceed the preset value (30 rpm in this example). ThrActOff0 and atmospheric pressure; where r ThrBfActLim is the preset value, which is 0.05 in this example; the preset time learning correction coefficient r Delay The update method is as follows:

[0104] Case 1: If the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct ThrActOff0 When it is greater than 9%, and the last preset time learning correction coefficient r Delay If the difference between the atmospheric pressure corresponding to the update and the current atmospheric pressure exceeds the preset value (±3kPa in this example), only the preset time learning correction coefficient r under the throttle opening of 9% is updated. Delay , it is not updated at other throttle openings, and the preset time learning correction coefficient r Delay The update calculation formula is: Among them, r Delay (z) is the preset time learning correction coefficient of the last self-learning update, k1 is the weighting coefficient, which is 0.01 in this example; if the engine enters the shutdown condition and the engine speed does not exceed the preset value, the throttle opening pct ThrActOff0 When it is greater than 9%, and the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ;

[0105] Second case: If the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct ThrActOff0 The value is one of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%. If the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure and the current atmospheric pressure exceeds the preset value (±3kPa in this example), only the preset time learning correction coefficient r under the corresponding throttle opening is updated. Delay , the preset time learning correction coefficient r is not updated at other throttle openings Delay , preset time learning correction coefficient r Delay The update calculation formula is: Among them, r Delay (z) is the preset time learning correction coefficient of the last self-learning update, k1 is the weighting coefficient, which is 0.01 in this example; if the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ;

[0106] The third case: If the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct ThrActOff0 The value is between two adjacent values ​​of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%. If the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure and the current atmospheric pressure exceeds the preset value (±3kPa in this example), only the preset time learning correction coefficient r of the corresponding throttle opening is updated. Delay , the preset time learning correction coefficient r is not updated at other throttle openings Delay ; If the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay The method for determining the corresponding throttle opening area is as follows: Assuming that the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct at the moment ThrActOff0 Between throttle openings A and B, where A and B are a pair of adjacent values ​​of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%, if the preset time t corresponding to the throttle opening A read before this update EngMovingDelay t A , the preset time t corresponding to the throttle opening B read before this update EngMovingDelay tB , determine the throttle opening pct ThrActOff Corresponding preset time learning correction coefficient r Delay Use r Delay (pct ThrActOff ) means:

[0107] where r Delay (pct ThrActOff )(z) is the throttle opening updated in the last self-learning, which is pct ThrActOff The preset time learning correction coefficient under the setting of throttle valve opening A and throttle valve opening B is updated at the same time, and the preset time learning correction coefficients of throttle valve opening A and throttle valve opening B are respectively updated with r Delay (A) and r Delay (B) means:

[0108]

[0109] Wherein k3 and k4 are both preset weighting coefficients. In this example, k3 is 0.85 and k4 is 0.85.

[0110] In this embodiment, the second method is:

[0111] When the throttle inlet pressure stable working condition judgment condition is met, obtaining the average value of the throttle inlet pressure and the average value of the throttle outlet pressure within a preset time;

[0112] Whether a throttle inlet pressure signal fails is determined based on the average throttle inlet pressure, the average throttle outlet pressure, and a self-learning correction coefficient.

[0113] Specifically, the second method is as follows:

[0114] When the throttle inlet pressure stable working condition judgment condition is met, obtain the average throttle inlet pressure within the preset time t3 Average throttle outlet pressure

[0115] like If the throttle valve inlet pressure signal fails, it is determined that the throttle valve inlet pressure signal fails; otherwise, it is determined that the throttle valve inlet pressure signal fails;

[0116] The preset time t3 is 2s in this example, Adpt It is a self-learning correction coefficient. The default value is 0. It can be saved when the vehicle is powered off.

[0117] Self-learning correction coefficient r AdptThe method of obtaining is as follows: record the number of times CNT3 that the throttle inlet pressure stable working condition judgment condition is met, and record the number of times CNT3 that the throttle inlet pressure stable working condition judgment condition is met. The number of times CNT4 is recorded after the throttle inlet pressure meets the stable working condition judgment condition The number of times CNT3, CNT4 and CNT5 are updated at most once in each driving cycle of the vehicle;

[0118] If CNT3 ≥ 200, CNT4 ≥ 160, and CNT5 ≤ 10, then r Adpt =r Adpt (z)-0.01;

[0119] If CNT3 ≥ 200, CNT4 ≤ 10, and CNT5 ≥ 130, then r Adpt =r Adpt (z)+0.015;

[0120] In other cases, r Adpt =r Adpt (z);

[0121] where r Adpt (z) is the self-learning correction coefficient of the last update; when CNT3 ≥ 200, the self-learning correction coefficient r Adpt After the update, CNT3, CNT4 and CNT5 are reset to 0 and the counting starts again when the next condition is met.

[0122] In this embodiment, the throttle inlet pressure stable operating condition is determined as follows:

[0123] (1) The engine is running;

[0124] (2) The target air intake volume is stable;

[0125] rho DesFilter (N) = K Rho ×[rho DesRaw (N)-rho DesFilter (N-1)]+rho DesFilter (N-1); where rho DesRaw is the target air intake volume, rho DesRaw (N) is the target intake volume of the Nth sampling period, rho DesFilter is the target intake volume after first-order low-pass filtering, rho DesFilter (N) is the filtered target intake volume of the Nth sampling period, rho DesFilter (N-1) is the filtered target intake air volume of the N-1th sampling period, N = 1, 2, 3..., rho DesFilter(0) is equal to the target intake air volume rho at the 0th sampling period DesRaw (0); Sampling period interval Δt, in this example it is 10ms. K Rho is the coefficient: (This example k Rho The calibration speed is 1000rpm. The purpose of this setting is to normalize the process. At different speeds, no special calibration is required. Only the k value at 1000 rpm needs to be calibrated. Rho , thereby reducing the calibration test work), where n is the engine speed, k Rho is the air volume filter coefficient, which is 0.02 in this example.

[0126] in|rho DesRaw (N)-rho DesFilter (N)| <min[rho DesRaw (N), rho DesFilter (N)]×r RhoLim The condition is continuously met for a period of time up to T Rho The latter indicates that the target intake air volume is in a stable state (the air volume fluctuation is small). RhoLim In this example, we take 0.05, T Rho In this example, 0.4s is used.

[0127] (3) The actual intake pressure at the throttle outlet is stable;

[0128] p ManFilter (N) = K Man ×[p Man (N)-p ManFilter (N-1)]+p ManFilter (N-1); where p Man is the throttle outlet intake pressure, p Man (N) is the throttle outlet intake pressure of the Nth sampling period, p ManFilter is the throttle outlet intake pressure after first-order low-pass filtering, p ManFilter (N) is the filtered throttle outlet intake pressure of the Nth sampling period, p ManFilter (N-1) is the filtered throttle outlet intake pressure of the N-1th sampling period, N = 1, 2, 3..., p ManFilter (0) is equal to the throttle outlet intake pressure p at the 0th sampling period Man (0); The sampling period interval Δt in this example is 10ms. K Man is the coefficient: (This example k Man The calibration speed is 1000rpm. The purpose of this setting is to normalize the process. At different speeds, no special calibration is required. Only the 4-cylinder engine and the k-axis with a speed of 1000 rpm need to be calibrated. Man , thereby reducing the calibration test work), where n is the engine speed, k Man is the throttle outlet intake pressure filter coefficient, which is 0.02 in this example.

[0129] In|p Man (N)-p ManFilter (N)| <min[p Man (N), p ManFilter (N)]×r ManLim The condition is continuously met for a period of time up to T Man The latter indicates that the intake pressure is in a stable state (the intake pressure fluctuation is small). ManLim In this example, we take 0.05, T Man In this example, 0.4s is used.

[0130] (4) The engine speed fluctuation does not exceed a preset range, which in this example is ±15 rpm;

[0131] (5) The opening of the boost actuator is equal to its full opening, which is the opening corresponding to the maximum boosting capacity of the supercharger;

[0132] (6) The throttle opening is greater than the preset value, which is 95% in this example;

[0133] (7) The throttle outlet pressure signal is not detected as a fault;

[0134] (8) The product of the engine's short-term fuel correction and the long-term fuel correction is within a preset range (0.97-1.03 in this example) and exceeds a preset time t2 (5s in this example). The acquisition of the short-term fuel correction can be found in the patent publication number CN113847155A, "A Method and Control System for Controlling Short-Term Fuel Correction of an Engine." The acquisition of the long-term fuel correction can be found in the patent publication number CN111412074A, "A Self-Learning Method for Long-Term Fuel Correction of a Gasoline Engine." If the product of the engine's short-term fuel correction and the long-term fuel correction is small, it means that the difference between the engine's requested fuel injection amount and the actual fuel injection amount is small, the engine's requested fuel injection amount calculated based on the intake volume is more accurate, the engine's intake volume is more accurate, and the post-throttle pressure sensor signal is accurate.

[0135] S2: Determine whether a throttle inlet pressure signal is faulty based on the results of the first method and the second method.

[0136] Specifically, in this embodiment, the method for determining whether the throttle inlet pressure signal is faulty according to the results of the first method and the second method is:

[0137] If during this driving cycle, the number of times the throttle inlet pressure signal is judged to be faulty by the second method is recorded as CNT1, and the number of times the throttle inlet pressure signal is judged to be faulty by the first method is recorded as CNT2, and CNT1>50, CNT2<2, then it is finally judged that the throttle inlet pressure signal is not faulty, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z) +0.03, and clear CNT1 and CNT2 to 0;

[0138] If during this driving cycle, the number of times the throttle inlet pressure signal is judged to be faulty by the second method is recorded as CNT1, and the number of times the throttle inlet pressure signal is judged to be faulty by the first method is recorded as CNT2, and CNT1<2, CNT2>50, then it is finally judged that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z) -0.04, and clear CNT1 and CNT2 to 0;

[0139] If during this driving cycle, the number of times the throttle inlet pressure signal is judged to be faulty by the second method is recorded as CNT1, and the number of times the throttle inlet pressure signal is judged to be faulty by the first method is recorded as CNT2, and CNT1>50, CNT2>50, then it is finally judged that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z);

[0140] In other cases, it is finally determined that the throttle inlet pressure signal has no fault, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z);

[0141] where r Adpt (z) is the self-learning correction coefficient of the last update; CNT1 and CNT2 are updated at most once in each driving cycle.

[0142] In summary, the present invention provides a method for monitoring engine pressure signal degradation in a hybrid vehicle, which can verify the rationality of the pressure signal of the pre-throttle pressure sensor.

[0143] It should be pointed out that, according to the needs of implementation, the various steps described in this application can be split into more steps, or two or more steps or partial operations of the steps can be combined into new steps to achieve the purpose of the present invention.

[0144] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for monitoring engine pressure signal degradation in a hybrid vehicle, characterized in that: include: Using the first method and the second method to check the throttle inlet pressure signal respectively; Determining the number of times the throttle inlet pressure signal fails according to the results of the first method and the second method, and determining whether the throttle inlet pressure signal fails according to the number of times the throttle inlet pressure signal fails; The first method is: when the throttle pressure verification condition is met, the throttle inlet pressure signal and the throttle post-pressure signal are read in real time; determining whether a fault occurs in the throttle inlet pressure signal according to the throttle inlet pressure signal, the throttle post-pressure signal, and a preset time; The second method is: when the throttle inlet pressure stable working condition judgment condition is met, obtaining the average value of the throttle inlet pressure and the average value of the throttle outlet pressure within a preset time; Whether a throttle inlet pressure signal fails is determined based on the average throttle inlet pressure, the average throttle outlet pressure, and a self-learning correction coefficient.

2. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 1, characterized in that: The first method is specifically as follows: When the throttle pressure verification condition is met, the throttle inlet pressure signal p is read in real time. ThrBfAct and the post-throttle pressure signal p ThrAftAct , if it appears: If the continuous occurrence time exceeds the preset time t1, it is determined that the throttle inlet pressure signal is faulty; Otherwise, it is determined that the throttle inlet pressure signal has no fault.

3. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 2, characterized in that: The throttle pressure verification conditions are: (1) The engine speed does not exceed the preset value for a period of time exceeding the preset time t EngMovingDelay ; (2) There is no malfunction in the atmospheric pressure sensor and the throttle body pressure sensor; (3) The difference between the atmospheric pressure signal and the throttle valve pressure signal is within a preset range; (4) The fluctuations of the atmospheric pressure signal and the post-throttle pressure signal do not exceed the preset range.

4. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 3, characterized in that: The preset time t EngMovingDelay =t EngMovingDelayRaw ×(1+r Delay ), the t EngMovingDelayRaw is the preset time initial value, where r Delay The correction coefficient is learned at the preset time. Its initial value is 0, and it is continuously learned and updated. It can be saved after the vehicle is powered off.

5. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 4, characterized in that: The preset time initial value t EngMovingDelayRaw Depends on the throttle opening pct when the engine speed does not exceed the preset value ThrActOff When the throttle opening pct ThrActOff When the values ​​are 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, and 9%, respectively, the preset time initial value t EngMovingDelayRaw The corresponding values ​​are 12000ms, 10000ms, 6000ms, 4000ms, 2000ms, 1200ms, 1000ms, 500ms, and 500ms.

6. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 5, characterized in that: The preset time learning correction coefficient r Delay The method to obtain is: When the first method is used to determine that the throttle inlet pressure signal is not faulty, the throttle inlet pressure signal is recorded from the time the engine enters a shutdown state and the engine speed does not exceed a preset value, and the throttle inlet pressure signal is filtered: ThrBfActFilter (N) = K ThrBf ×[p ThrBfAct (N)-p ThrBfActFilter (N-1)]+p ThrBfActFilter (N-1); where p ThrBfAct is the throttle inlet pressure, p ThrBfAct (N) is the throttle inlet pressure of the Nth sampling period, p ThrBfActFilter is the throttle inlet pressure after first-order low-pass filtering, p ThrBfActFilter (N) is the filtered throttle inlet pressure of the Nth sampling period, p ThrBfActFilter (N-1) is the filtered throttle inlet pressure of the N-1th sampling period, N = 1, 2, 3..., p ThrBfActFilter (0) is equal to the throttle inlet pressure p at the 0th sampling period ThrBfAct (0); wherein the 0th sampling period is the sampling period for reading the moment when the engine enters the shutdown state and the engine speed does not exceed the preset value, and the sampling period interval is Δt; K ThrBf is the filter coefficient; Record the time from when the engine enters the shutdown state and the engine speed does not exceed the preset value to when the engine stops. ThrBfAct (N)-p ThrBfActFilter (N)|>min[p ThrBfAct (N), p ThrBfActFilter (N)]×r ThrBfActLim The shortest time is t0, and the throttle opening pct when the engine enters the shutdown condition and the engine speed does not exceed the preset value is recorded. ThrActOff0 and atmospheric pressure; where r ThrBfActLim is a preset value; the preset time learning correction coefficient r Delay The update method is as follows: First case: if the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct at the moment ThrActOff0 When it is greater than 9%, and the last preset time learning correction coefficient r Delay If the difference between the atmospheric pressure corresponding to the update and the current atmospheric pressure exceeds the preset value, only the preset time learning correction coefficient r under the throttle opening of 9% is updated. Delay , the preset time learning correction coefficient r is not updated at other throttle openings. Delay The update calculation formula is: Among them, r Delay (z) is the preset time learning correction coefficient of the last self-learning update, k1 is the weighting coefficient; if the engine enters the shutdown condition and the engine speed does not exceed the preset value, the throttle opening pct at the moment ThrActOff0 When it is greater than 9%, and the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ; Second situation: if the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct at the moment ThrActOff0 The value is one of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%. If the last preset time learning correction coefficient r Delay If the difference between the atmospheric pressure corresponding to the update and the current atmospheric pressure exceeds the preset value, only the preset time learning correction coefficient r under the corresponding throttle opening is updated. Delay , the preset time learning correction coefficient r is not updated at other throttle openings Delay , the preset time learning correction coefficient r Delay The update calculation formula is: Among them, r Delay (z) is the preset time learning correction coefficient of the last self-learning update, k1 is the weighting coefficient; if the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ; The third case: if the engine enters the shutdown state and the engine speed does not exceed the preset value, the throttle opening pct at the time ThrActOff0 The value is between two adjacent values ​​of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%. If the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure and the current atmospheric pressure exceeds the preset value during the update, only the preset time learning correction coefficient r of the corresponding throttle opening will be updated. Delay , the preset time learning correction coefficient r is not updated at other throttle openings Delay ; If the last preset time learning correction coefficient r Delay If the difference between the corresponding atmospheric pressure during the update and the current atmospheric pressure does not exceed the preset value, the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay The method for determining the corresponding throttle opening area is as follows: Assuming that the engine enters the shutdown state and the engine speed does not exceed the preset value at the moment of the throttle opening pct ThrActOff0 Between throttle openings A and B, where A and B are a pair of adjacent values ​​of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%, if the throttle opening A read before this update corresponds to the preset time t EngMovingDelay t A , the preset time t corresponding to the throttle opening B read before this update EngMovingDelay t B , determine the throttle opening pct ThrActOff The corresponding preset time learning correction coefficient r Delay Use r Delay (pct ThrActOff ) means: where r Delay (pct ThrActOff )(z) is the throttle opening updated in the last self-learning, which is pct ThrActOff The preset time learning correction coefficient under the setting time, k2 is the weighting coefficient; while updating the preset time learning correction coefficient of the throttle opening A and the throttle opening B, respectively, with r Delay (A) and r Delay (B) means: Wherein k3 and k4 are both preset weighting coefficients.

7. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 6, characterized in that: In the second method, the specific method for determining whether the throttle inlet pressure signal is faulty is: When the throttle inlet pressure stable working condition judgment condition is met, obtain the average throttle inlet pressure within the preset time t3 Average throttle outlet pressure like If the throttle valve inlet pressure signal fails, it is determined that the throttle valve inlet pressure signal fails; otherwise, it is determined that the throttle valve inlet pressure signal fails; wherein the r Adpt It is a self-learning correction coefficient. The default value is 0. It can be saved when the vehicle is powered off.

8. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 7, characterized in that: The self-learning correction coefficient r Adpt The method for obtaining is as follows: record the number of times CNT3 that the throttle inlet pressure stable working condition judgment condition is met, and record the number of times CNT3 that the throttle inlet pressure stable working condition judgment condition is met. The number of times CNT4 is recorded after the throttle inlet pressure stable working condition judgment condition is met The number of times CNT3, CNT4 and CNT5 are updated at most once in each driving cycle of the vehicle; If CNT3 ≥ 200, CNT4 ≥ 160, and CNT5 ≤ 10, then r Adpt =r Adpt (z) - 0.01; If CNT3 ≥ 200, CNT4 ≤ 10, and CNT5 ≥ 130, then r Adpt =r Adpt (z)+0.015; In other cases, r Adpt =r Adpt (z); where r Adpt (z) is the self-learning correction coefficient of the last update; when CNT3 ≥ 200, then the self-learning correction coefficient r Adpt After the update, CNT3, CNT4 and CNT5 are reset to 0 and the counting starts again when the next condition is met.

9. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 1, characterized in that: The throttle inlet pressure stable working condition judgment condition is: (1) The engine is running; (2) The target air intake volume is stable; (3) The actual intake pressure at the throttle outlet is stable; (4) The engine speed fluctuation does not exceed the preset range; (5) The opening of the boost actuator is equal to its full opening; (6) The throttle opening is greater than the preset value; (7) The throttle outlet pressure signal is not detected as a fault; (8) The product of the engine's short-term fuel correction and the long-term fuel correction is within the preset range and exceeds the preset time.

10. The method for monitoring engine pressure signal degradation of a hybrid vehicle according to claim 8, characterized in that: The method for determining the number of times the throttle inlet pressure signal fails according to the results of the first method and the second method, and determining whether the throttle inlet pressure signal fails according to the number of times the throttle inlet pressure signal fails is: If during this driving cycle, the second method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT1, and the first method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT2, and CNT1>50, CNT2<2, then it is finally determined that the throttle inlet pressure signal has no fault, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z) +0.03, and clear CNT1 and CNT2 to 0; If during this driving cycle, the second method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT1, and the first method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT2, and CNT1<2, CNT2>50, then it is finally determined that the throttle inlet pressure signal fails, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z) -0.04, and clear CNT1 and CNT2 to 0; If during this driving cycle, the second method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT1, and the first method determines that the number of times the throttle inlet pressure signal fails is recorded as CNT2, and CNT1>50, CNT2>50, then it is finally determined that the throttle inlet pressure signal fails, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z); In other cases, it is finally determined that the throttle inlet pressure signal has no fault, and the self-learning correction coefficient r is updated. Adpt =r Adpt (z); where r Adpt (z) is the self-learning correction coefficient of the last update; CNT1 and CNT2 are updated at most once in each driving cycle.

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