Throttle inlet pressure signal verification method

Abstract

The application discloses a method for checking a throttle inlet pressure signal, comprising the following steps: checking the throttle inlet pressure signal by using a first method, a second method and a third method respectively; and judging whether the throttle inlet pressure signal is faulty according to the results of the first method, the second method and the third method. The method provided by the application can check the rationality of the pressure signal of the pressure sensor before the throttle.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engine control, in particular to a throttle inlet pressure signal checking method. BACKGROUND

[0002] As an important parameter for throttle and supercharging system control, throttle inlet pressure will affect vehicle power, drivability and fuel economy, so it is particularly important to check throttle inlet pressure signal abnormity.

[0003] The patent with application number 202110982953.2 discloses "a throttle flow calculation method, device, equipment and readable storage medium", which estimates EGR method flow by using throttle front pressure (inlet pressure) and rear pressure (outlet pressure), but does not propose a throttle inlet pressure signal checking method.

[0004] The patent with application number 202110518171.3 discloses "a measurement method and device of EGR mass flow and exhaust gas treatment system", which estimates EGR method flow by using throttle front pressure (inlet pressure) and rear pressure (outlet pressure), but does not propose a throttle inlet pressure signal checking method. SUMMARY

[0005] The present application solves the technical problem of the prior art by providing a throttle inlet pressure signal checking method, which can check the rationality of the throttle front pressure sensor pressure signal.

[0006] To achieve the above-mentioned purpose, according to one aspect of the present application, a throttle inlet pressure signal checking method is provided, comprising:

[0007] The throttle inlet pressure signal is checked by using the first method, the second method and the third method respectively;

[0008] According to the results of the first method, the second method and the third method, it is judged whether the throttle inlet pressure signal has a fault.

[0009] In the above-mentioned scheme, the first method is to read the throttle inlet pressure signal and the throttle rear pressure signal in real time when the throttle pressure checking condition is met;

[0010] According to the throttle inlet pressure signal, the throttle rear pressure signal and the preset time, it is judged whether the throttle inlet pressure signal has a fault;

[0011] In the above-mentioned scheme, the first method is specifically to read the throttle inlet pressure signal p ThrBfAct and the throttle rear pressure signal pThrAftAct If the following conditions are met: and the time of continuous occurrence exceeds a preset time t1, it is determined that the throttle inlet pressure signal is faulty; otherwise, it is determined that the throttle inlet pressure signal is not faulty.

[0012] In the above scheme, the throttle pressure checking condition is:

[0013] (1) The length of time during which the engine speed does not exceed a preset value exceeds a preset time t EngMovingDelay ;

[0014] (2) Both the atmospheric pressure sensor and the throttle rear pressure sensor are not faulty;

[0015] (3) The difference between the atmospheric pressure signal and the throttle rear pressure signal is within a preset range;

[0016] (4) The fluctuations of the atmospheric pressure signal and the throttle rear pressure signal are both not more than a preset range;

[0017] Where t EngMovingDelay = t EngMovingDelayRaw × (1 + r Delay ), t EngMovingDelayRaw is a preset time initial value, r Delay is a preset time learning correction coefficient, which has an initial value of 0 and is constantly updated and saved after the vehicle is powered off.

[0018] The greater the throttle opening degree pct ThrActOff is away from the natural opening degree (the opening degree of the throttle motor when it is not controlled, i.e. the opening degree by default when it is not powered on) at the time of shutdown, the longer the intake system airflow needs to be delayed to enter the throttle inlet pressure signal checking. Based on test verification, to ensure the accuracy of the throttle inlet pressure signal checking, the preset time initial value t EngMovingDelayRaw is calibrated in relation to the throttle opening degree pct ThrActOff , and the results are shown in the preset time initial value t EngMovingDelayRaw vs. the throttle opening degree pct ThrActOff table.

[0019] The preset time initial value t EngMovingDelayRaw depends on the throttle opening degree pct ThrActOff at the time when the engine speed does not exceed a preset value, and the preset time initial value t EngMovingDelayRaw vs. the throttle opening degree pct ThrActOff table is as follows:

[0020]

[0021] The reason for focusing only on throttle opening between 0% and 9% is that when the engine requests a shutdown, the throttle valve first closes fully and then slowly returns to its natural opening to quickly reduce engine torque and achieve a rapid shutdown. EngMovingDelayRaw The shorter the time, the greater the fluctuation in throttle inlet pressure, and the pressure does not maintain the stable pressure value at the moment the engine stops. If t EngMovingDelayRaw If the time is too long, the pressure signal verification and detection may be delayed, the pressure signal verification efficiency may be low, and the controller may need to be powered for a long time, resulting in power consumption.

[0022] The throttle opening (pct) ThrActOff The method is determined by using the electronic throttle control method of an exhaust gas turbocharged engine (see Chinese Patent Publication No. CN111255581A for details).

[0023] In the above scheme, the preset time learning correction coefficient r Delay The method for obtaining it is as follows:

[0024] When the first method determines that the throttle inlet pressure signal is not faulty, the throttle inlet pressure signal is recorded starting when the engine enters a shutdown state and the engine speed does not exceed a preset value, and the throttle inlet pressure signal is filtered: p ThrBfActFilter (N)=K ThrBf ×[p ThrBfAct (N)-p ThrBfActFilter [(N-1)]+p ThrBfActFilter (N-1); where p ThrBfAct p is the throttle inlet pressure. ThrBfAct (N) represents the throttle inlet pressure during the Nth sampling period, p ThrBfActFilter p is the throttle inlet pressure after first-order low-pass filtering. ThrBfActFilter (N) represents the filtered throttle inlet pressure during the Nth sampling period, p ThrBfActFilter (N-1) represents the filtered throttle inlet pressure during the (N-1)th sampling period, where N = 1, 2, 3, ..., p ThrBfActFilter (0) equals the throttle inlet pressure p at the 0th sampling period. ThrBfAct (0); where the 0th sampling period is the sampling period for reading the moment when the engine enters the shutdown condition and the engine speed does not exceed the preset value, and the sampling period interval is Δt; K ThrBf These are the filter coefficients;

[0025] Record the time from when the engine enters the shutdown condition and the engine speed does not exceed the preset value until the occurrence of |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 at the moment when the engine enters the shutdown condition and the engine speed does not exceed the preset value. ThrActOff0 and atmospheric pressure; where r ThrBfActLim The preset value is used; the preset time learning correction coefficient r is set to... Delay The update methods are as follows:

[0026] First scenario: If the engine enters a shutdown state and the engine speed does not exceed the preset throttle opening value (pct) at that time. ThrActOff0 When it is greater than 9%, and the previous preset time learning correction coefficient r Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure exceeds a preset value, then only the preset time learning correction coefficient r at a throttle opening of 9% will be updated. Delay The preset time learning correction coefficient r is not updated at other throttle openings. Delay The update calculation formula is: Where, r Delay (z) represents the preset time learning correction coefficient of the last self-learning update, and k1 is the weighting coefficient; if the engine enters the shutdown condition and the engine speed does not exceed the preset value of the throttle opening pct at that time. ThrActOff0 When it is greater than 9%, and the previous preset time learning correction coefficient r Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure does not exceed a preset value, then the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ;

[0027] Second scenario: If the engine enters a shutdown state and the engine speed does not exceed the preset throttle opening value (pct) at that time. ThrActOff0 The value can be one of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, or 9%, if the previous preset time learning correction coefficient r Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure exceeds a preset value, then only the preset time learning correction coefficient r at 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: Where, r Delay (z) represents the preset time learning correction coefficient from the previous self-learning update, and k1 is the weighting coefficient; the preset time learning correction coefficient r DelayIf the difference between the atmospheric pressure at the time of update and the current atmospheric pressure does not exceed a preset value, then the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ;

[0028] Third scenario: If the engine enters a shutdown state and the engine speed does not exceed the preset throttle opening value (pct) at that time. ThrActOff0 The value is located between two adjacent values ​​in the range of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, and 9%. If the previous preset time learning correction coefficient r... Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure exceeds a preset value, then only the preset time learning correction coefficient r for 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 learning correction coefficient r for the previous preset time is... Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure does not exceed a preset value, then 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 range is as follows: Assume the throttle opening is pct at the time when the engine enters a shutdown state and the engine speed does not exceed a preset value. ThrActOff0 The value is between throttle opening A and B, where A and B are a pair of adjacent values ​​from 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, and 9%. If the preset time t corresponds to the throttle opening A read before this update... EngMovingDelay For t A The preset time t corresponding to the throttle opening B read before this update EngMovingDelay For t B Determine the throttle opening pct ThrActOff The corresponding preset time learning correction coefficient r Delay Use r Delay (pct ThrActOff If ) indicates that:

[0029] Where r Delay (pct ThrActOff (z) represents the throttle opening value updated during the last self-learning process, which is pct. ThrActOff The preset time learning correction coefficient is set below, and k2 is the weighting coefficient; simultaneously, the preset time learning correction coefficients for throttle opening A and throttle opening B are updated, respectively using r Delay (A) and r Delay (B) indicates:

[0030]

[0031] Wherein k3, k4 are preset weighting coefficients.

[0032] The updated throttle opening degree pct under the shutdown condition ThrActOff The preset time learning correction coefficient r corresponding to the throttle opening degree pct under the shutdown condition Delay The throttle opening degree pct under the shutdown condition ThrActOff are stored separately and updated in the subsequent vehicle driving cycle. EngMovingDelay The judgment of the throttle pressure checking condition.

[0033] In the above scheme, the second method is:

[0034] Filtering the engine speed to obtain a filtered engine speed;

[0035] Reading the throttle inlet pressure signal for a plurality of times in succession, and estimating the estimated value of the throttle inlet pressure signal in the next sampling period through the throttle inlet pressure signal at a certain time;

[0036] Determining the sampling number for throttle inlet pressure signal checking;

[0037] Judging whether the throttle inlet pressure signal is faulty according to the filtered engine speed, the estimated value of the throttle inlet pressure signal, and the sampling number.

[0038] In the above scheme, in the second method:

[0039] Obtaining a filtered engine speed n Filt The calculation method is as follows: the filtered engine speed n Filt (m) of the current sampling period is calculated according to the filtered engine speed n Filt (m+1) of the next sampling period and the original real-time engine speed n Raw The following relationship is established:

[0040] n Filt (m+1) = k × n Raw +(1-k) × n Filt (m);

[0041] Wherein m = 0, 1, 2, …, and n Filt (0) is 0; k is a filtering coefficient.

[0042] The method for estimating the estimated value of the throttle inlet pressure signal in the next sampling period through the throttle inlet pressure signal at a certain time is as follows: reading the latest continuous N (N is not less than 7) throttle inlet pressure signals in real time, and forming an array [p ThrBfAct (0), p ThrBfAct (1), pThrBfAct (N-1)…], wherein p ThrBfAct (0) is the throttle inlet pressure signal read in the current sampling period, p ThrBfAct (N-1) is the throttle inlet pressure signal read in the previous N-1 sampling periods, and so on to obtain the throttle inlet pressure signal p ThrBfAct (k) of the previous kth sampling period, k = 0, 1, 2, …, N-1; the estimated value p ThrBfAct (k-1)' of the throttle inlet pressure signal of the previous k-1th sampling period is estimated:

[0043]

[0044] The estimated value p ThrBfAct (k+1)' of the next throttle inlet pressure signal when k = 0 is: ThrBfAct (1)' = 0 (kPa / s); the rate of change of the throttle inlet pressure signal p (k) when k = 0 is: ThrBfAct (k) = Δp ThrBfAct (0) = 0 (kPa / s); the rate of change of the throttle inlet pressure signal p ThrBfAct (k+1)' = p ThrBfAct (1)' = 0 (kPa / s); Δt is the sampling period; t c is the pressure estimation filtering time period;

[0045] The method for determining the sampling number V for throttle inlet pressure signal checking is as follows: the value of Filt is calculated according to the filtered engine speed n Raw and the original real-time engine speed n ; wherein When the value of is between any two adjacent numbers in 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.28, 0.3, 0.32, the sampling number V takes the value of the sampling number V corresponding to the larger number of the two adjacent numbers; wherein the and the sampling number V are as follows:

[0046]

[0047] The larger the value of , the greater the engine speed fluctuation, and more sampling number of pressure signals are needed to determine whether the throttle inlet pressure signal has failed.

[0048] The method for determining whether the throttle inlet pressure signal is faulty according to the filtered engine speed, the estimated value of the throttle inlet pressure signal and the sampling number is:

[0049] When the throttle inlet pressure judgment condition is met, the estimated value p of the throttle inlet pressure signal in the current sampling period is obtained for V consecutive times ThrBfAct (V-1) and the actual value p of the throttle inlet pressure signal read by the sensor ThrBfAct (V-1);

[0050] When V = 1, if |p ThrBfAct (0)'-p ThrBfAct (0)| is greater than a preset value C1, it is determined that the throttle inlet pressure signal has a preliminary fault, otherwise it is determined that the throttle inlet pressure signal has no preliminary fault; wherein the preset value C1 = 5x(1+r Lrn ), r Lrn is a self-learning correction coefficient of the preset value C1, and its default value is 0, which can be saved after the vehicle is powered off;

[0051] When V = 2, if |p ThrBfAct (0)'-p ThrBfAct (0)|, |p ThrBfAct (1)'-p ThrBfAct (1)| are greater than the preset value C1, it is determined that the throttle inlet pressure signal has a preliminary fault, otherwise it is determined that the throttle inlet pressure signal has no preliminary fault;

[0052] When V = 3, if |p ThrBfAct (0)'-p ThrBfAct (0)|, |p ThrBfAct (1)'-p ThrBfAct (1)|, |p ThrBfAct (2)'-p ThrBfAct (2)| are greater than the preset value C1, it is determined that the throttle inlet pressure signal has a preliminary fault, otherwise it is determined that the throttle inlet pressure signal has no preliminary fault;

[0053] When V = 4, if |p ThrBfAct (0)'-p ThrBfAct (0)|, |p ThrBfAct (1)'-p ThrBfAct (1)|, |p ThrBfAct (2)'-p ThrBfAct (2)|, |p ThrBfAct (3)'-p ThrBfAct (3)| are greater than the preset value C1, it is determined that the throttle inlet pressure signal has a preliminary fault, otherwise it is determined that the throttle inlet pressure signal has no preliminary fault;

[0054] When V=5, if |p ThrBfAct (0)'-p ThrBfAct (0)|, |p ThrBfAct (1)'-p ThrBfAct (1)|, |p ThrBfAct (2)'-p ThrBfAct (2)|, |p ThrBfAct (3)'-p ThrBfAct (3)|, |p ThrBfAct (4)'-p ThrBfAct (4)| are all greater than the preset value C1, it is judged that the throttle inlet pressure signal has a preliminary fault, otherwise it is judged that the throttle inlet pressure signal has no preliminary fault;

[0055] When V=6, if |p ThrBfAct (0)'-p ThrBfAct (0)|, |p ThrBfAct (1)'-p ThrBfAct (1)|, |p ThrBfAct (2)'-p ThrBfAct (2)|, |p ThrBfAct (3)'-p ThrBfAct (3)|, |p ThrBfAct (4)'-p ThrBfAct (4)|, |p ThrBfAct (5)'-p ThrBfAct (5)| are all greater than the preset value C1, it is judged that the throttle inlet pressure signal has a preliminary fault, otherwise it is judged that the throttle inlet pressure signal has no preliminary fault;

[0056] The self-learning correction coefficient r Lrn of the preset value C1 is updated as follows: the effective number CNT1 of times when it is judged that the throttle inlet pressure signal has no preliminary fault and the invalid number CNT2 of times when it is judged that the throttle inlet pressure signal has a preliminary fault are recorded respectively under different sampling numbers V, wherein CNT1 and CNT2 are updated at most once per vehicle driving cycle: if CNT1≥160 and CNT2≤10, r Lrn (z) = r Lrn (z) - 0.005; if CNT1≤10 and CNT2≥160, r Lrn (z) = r Lrn (z) + 0.012; otherwise, r Lrn (z) = r Lrn (z); wherein r L rn(z) is the self-learning correction coefficient of the preset value C1 updated last time;

[0057] When CNT1+CNT2>200, CNT1180, and If yes, it is judged that the throttle inlet pressure signal is faulty, otherwise it is judged that the throttle inlet pressure signal is not faulty; and when it is judged that the throttle inlet pressure signal is faulty, CNT1 and CNT2 are cleared, and the counting is restarted after the next condition is met.

[0058] In the above scheme, the throttle inlet pressure judgment condition is:

[0059] (1) The actual engine intake air density into the cylinder fluctuation does not exceed a preset value; too large fluctuation leads to reduced detection accuracy;

[0060] (2) The throttle opening fluctuation does not exceed a preset value; too large fluctuation leads to reduced detection accuracy;

[0061] (3) The engine operating time in the current engine driving cycle exceeds a preset time.

[0062] In the above scheme, the third method is: when the throttle inlet pressure stable working condition judgment condition is met, the average value of the throttle inlet pressure and the average value of the throttle outlet pressure in a preset time are obtained.

[0063] According to the average value of the throttle inlet pressure, the average value of the throttle outlet pressure and the self-learning correction coefficient, it is judged whether the throttle inlet pressure signal is faulty.

[0064] In the above scheme, the third method is specifically:

[0065] When the throttle inlet pressure stable working condition judgment condition is met, the average value of the throttle inlet pressure in a preset time t3 is obtained and the average value of the throttle outlet pressure

[0066] If , it is judged that the throttle inlet pressure signal is faulty, otherwise it is judged that the throttle inlet pressure signal is not faulty; wherein r Adpt is a self-learning correction coefficient, the default value is 0, which can be saved when the vehicle is powered off;

[0067] The self-learning correction coefficient r Adpt is obtained as follows: record the number of times CNT3 that the throttle inlet pressure stable working condition judgment condition is met, record the number of times CNT4 that the throttle inlet pressure stable working condition judgment condition is met , record the number of times CNT5 that the throttle inlet pressure stable working condition judgment condition is met , and the CNT3, CNT4 and CNT5 are updated at most once per driving cycle of the vehicle;

[0068] If CNT3≥200, CNT4≥160, and CNT5≤10, then r Adpt = r Adpt (z) - 0.01

[0069] If CNT3≥200, CNT4≤10, and CNT5≥130, then r Adpt = r Adpt (z) + 0.015

[0070] Otherwise, r Adpt = r Adpt (z)

[0071] where r Adpt (z) is the last updated self-learning correction coefficient; when CNT3≥200, then the self-learning correction coefficient r Adpt is updated, and after the update, CNT3, CNT4, and CNT5 are all reset to 0, until the next condition is met to start accumulating the count again.

[0072] In the above scheme, the throttle inlet pressure stable working condition judgment condition is:

[0073] (1) the engine is in operation;

[0074] (2) the target intake amount is stable;

[0075] (3) the actual intake pressure at the throttle outlet is stable;

[0076] (4) the engine speed fluctuation does not exceed a preset range;

[0077] (5) the boost actuator opening degree is equal to its full opening degree, which is the opening degree corresponding to the maximum boost capacity of the supercharger;

[0078] (6) the throttle opening degree is greater than a preset value;

[0079] (7) the throttle outlet pressure signal has not detected a fault;

[0080] (8) the product of the engine short-term fuel correction and the long-term fuel correction is within a preset range and exceeds a preset time t2.

[0081] In the above scheme, the method for judging whether the throttle inlet pressure signal has a fault according to the results of the first method, the second method, and the third method is:

[0082] If, during this driving cycle, only the second method determines that the throttle inlet pressure signal is faulty, but both the first and third methods determine that the throttle inlet pressure signal is not faulty, then the final determination is that the throttle inlet pressure signal is not faulty, and the self-learning correction coefficient r of the preset value C1 is... Lrn =r Lrn (z)+0.3, the self-learning correction coefficient r Adpt =r Adpt (z)-0.005;

[0083] If, during this driving cycle, only the second method determines that the throttle inlet pressure signal is not faulty, but both the first and third methods determine that the throttle inlet pressure signal is faulty, then the final determination is that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r of the preset value C1... Lrn =r Lrn (z)-0.2, the self-learning correction coefficient r Adpt =r Adpt (z)+0.002;

[0084] If, during this driving cycle, only the third method determines that the throttle inlet pressure signal is faulty, but both the first and second methods determine that the throttle inlet pressure signal is not faulty, then the final determination is that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r of the preset value C1... Lrn =r Lrn (z)+0.3, the self-learning correction coefficient r Adpt =r Adpt (z)+0.008;

[0085] If, during this driving cycle, only the third method determines that the throttle inlet pressure signal is not faulty, but both the first and second methods determine that the throttle inlet pressure signal is faulty, then the final determination is that the throttle inlet pressure signal is not faulty, and the self-learning correction coefficient r of the preset value C1 is... Lrn =r Lrn (z)-0.2, the self-learning correction coefficient r Adpt =r Adpt (z)-0.01;

[0086] If, during this driving cycle, both the second method and the third method determine that the throttle inlet pressure signal is faulty, but the first method determines that the throttle inlet pressure signal is not faulty, then the final determination is that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r of the preset value C1... Lrn =r Lrn(z)-0.01, the self-learning correction coefficient r of the preset value C1 Adpt = r Adpt (z)-0.01

[0087] If the first method, the second method and the third method all judge that the throttle inlet pressure signal is faulty in the current driving cycle, it is finally judged that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r of the preset value C1 Lrn = r Lrn (z)+0.02, the self-learning correction coefficient r of the preset value C1 Adpt = r Adpt (z)+0.008

[0088] If the first method, the second method and the third method all judge that the throttle inlet pressure signal is faulty in the current driving cycle, it is finally judged that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r of the preset value C1 Lrn = r Lrn (z), the self-learning correction coefficient r of the preset value C1 Adpt = r Adpt (z)

[0089] Otherwise, it is finally judged that the throttle inlet pressure signal is not faulty, and the self-learning correction coefficient r of the preset value C1 Lrn = r Lrn (z), the self-learning correction coefficient r of the preset value C1 Adpt = r Adpt (z)

[0090] Wherein r Lrn (z) is the self-learning correction coefficient of the preset value C1 updated last time; r Adpt (z) is the self-learning correction coefficient updated last time.

[0091] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects:

[0092] The present application provides a throttle inlet pressure signal checking method, which checks the throttle inlet pressure signal under engine shutdown conditions, engine transient conditions (any various operating conditions) and steady state conditions, can accurately judge pressure abnormalities, and constantly updates various self-learning parameters during pressure signal checking, thereby improving the accuracy of subsequent throttle inlet pressure signal checking. BRIEF DESCRIPTION OF DRAWINGS

[0093] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0094] Figure 1 This is a schematic diagram of the intake system of the exhaust gas turbocharged engine in this embodiment.

[0095] Figure 2 This is a flowchart illustrating the throttle inlet pressure signal verification method in an embodiment of the present invention. Detailed Implementation

[0096] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be 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 illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0097] It should be understood that the sequence number of each step in the embodiment does not imply 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 embodiments of this application.

[0098] Example 1

[0099] The main components of the intake system of the turbocharged exhaust engine upon which this invention is based include: atmospheric pressure sensor, turbocharger, electronic wastegate, intercooler, pre-throttle temperature and pressure sensor, throttle body, post-throttle intake temperature and pressure sensor, carbon canister solenoid valve, EGR, VVT system, etc. Figure 1 As shown in the diagram. The atmospheric pressure sensor reads atmospheric pressure and is installed on the PCB board of the ECU controller. The turbocharger includes the turbocharger body and a wastegate valve; the boost pressure is controlled by adjusting the opening of the wastegate valve. The electronic pressure relief valve opens to prevent airflow from oscillating within the turbocharger compressor when the engine requests reduced torque, thus improving turbocharger surge, engine life, and NVH (noise, vibration, and harshness). The throttle body temperature and pressure sensor reads the temperature and pressure of the boosted gas before the throttle body. The intercooler is a mechanical component, uncontrolled, located between the turbocharger compressor and the throttle body, cooling the boosted gas. The throttle body intake air temperature and pressure sensor reads the temperature and pressure of the boosted gas before the throttle body. The carbon canister solenoid valve introduces fuel vapor into combustion and prevents it from evaporating into the atmosphere.

[0100] EGR, i.e. exhaust gas recirculation, sends part of the exhaust gas discharged by the engine back to the intake manifold and enters the cylinder again with fresh mixture; VVT is used to adjust the intake (exhaust) amount, valve opening and closing time, angle, and adjust the amount of air entering the cylinder. The throttle inlet pressure signal verification in the application verifies the reasonableness of the pressure signal of the pressure sensor before the throttle.

[0101] According to one aspect of the application, a throttle inlet pressure signal verification method is provided, referring to Figure 2 , comprising:

[0102] S1, respectively using the first method, the second method, the third method to verify the throttle inlet pressure signal.

[0103] Specifically, in this embodiment, the first method is: when the throttle pressure verification condition is met, the throttle inlet pressure signal and the throttle rear pressure signal are read in real time;

[0104] According to the throttle inlet pressure signal, the throttle rear pressure signal and the preset time, it is judged whether the throttle inlet pressure signal fails.

[0105] Among them, the first method is specifically: when the throttle pressure verification condition is met, the throttle inlet pressure signal p ThrBfAct and the throttle rear pressure signal p ThrAftAct , if: And the continuous occurrence time exceeds the preset time t1 (this example takes 0.5s), it is determined that the throttle inlet pressure signal fails; otherwise, it is determined that the throttle inlet pressure signal does not fail.

[0106] In this embodiment, the throttle pressure verification condition is:

[0107] (1) The length of time when the engine speed does not exceed the preset value (this example takes 30rpm) exceeds the preset time t EngMovingDelay ;

[0108] Among them, t EngMovingDelay =t EngMovingDelayRaw ×(1+r Delay ), t EngMovingDelayRaw is the initial value of the preset time, r Delay is the preset time learning correction coefficient, its initial value is 0 and is constantly learning and updating, and can be saved after the vehicle is powered off.

[0109] The throttle opening degree pct ThrActOffThe closer the throttle opening is to the natural opening (the natural opening refers to the opening of the throttle motor without control, i.e. the opening when the default is not powered on, and in this example, the natural opening of the engine throttle is between 7% and 9%), the longer the intake system airflow needs to be delayed to enter the throttle inlet pressure signal check. Based on test verification, to ensure the accuracy of the throttle inlet pressure signal check, the preset time initial value t EngMovingDelayRaw in connection with the throttle opening pct ThrActOff , the result is the preset time initial value t EngMovingDelayRaw in connection with the throttle opening pct ThrActOff The table is as follows.

[0110] The preset time initial value t EngMovingDelayRaw is determined by the throttle opening pct ThrActOff when the engine speed does not exceed the preset value, wherein the preset time initial value t EngMovingDelayRaw in connection with the throttle opening pct ThrActOff The table is as follows.

[0111]

[0112] The reason for only focusing on the throttle opening between 0% and 9% is that when the engine requests to stop, the throttle is closed first and then slowly enters the natural opening to quickly reduce the engine torque and achieve rapid stop.t EngMovingDelayRaw The shorter the time, the greater the fluctuation of the throttle inlet pressure at this time, which does not maintain the stable pressure value at the engine stop time. If t EngMovingDelayRaw is too long, it may cause the pressure signal check to be detected late, the pressure signal check efficiency is low, and the controller needs to be powered for a long time, resulting in power consumption.

[0113] The throttle opening pct ThrActOff is determined by using the control method of the electronic throttle of the exhaust turbocharged engine (for details, refer to Chinese Patent No. CN111255581A).

[0114] (2) The atmospheric pressure sensor and the throttle rear pressure sensor are both not faulty;

[0115] (3) The difference between the atmospheric pressure signal and the throttle rear pressure signal is within a preset range, and in this example, ±0.3kPa;

[0116] (4) The fluctuations of the atmospheric pressure signal and the throttle rear pressure signal do not exceed a preset range, and in this example, ±0.1kPa.

[0117] In this embodiment, the preset time learning correction coefficient r Delay is obtained by the following method:

[0118] 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 when the engine enters the shutdown working condition and the engine speed does not exceed a preset value (30 rpm in this example), and the throttle inlet pressure signal is filtered: p 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 in the Nth sampling period, p ThrBfActFilter is the first-order low-pass filtered throttle inlet pressure, p ThrBfActFilter (N) is the filtered throttle inlet pressure in the Nth sampling period, p ThrBfActFilter (N-1) is the filtered throttle inlet pressure in the (N-1)th sampling period, N = 1, 2, 3,..., p ThrBfActFilter (0) is equal to the throttle inlet pressure p ThrBfAct (0) at the 0th sampling period; where the 0th sampling period is the sampling period at the time when the engine enters the shutdown working condition and the engine speed does not exceed a preset value (30 rpm in this example), the sampling period interval time is Δt, and in this example, Δt is 10 ms; K ThrBf is the filtering coefficient, which is 0.02 in this example;

[0119] The shortest time from the time when the engine enters the shutdown working condition and the engine speed does not exceed a preset value (30 rpm in this example) to the time when |p ThrBfAct (N) - p ThrBfActFilter (N)|>min[p ThrBfAct (N), p ThrBfActFilter (N)]×r ThrBfActLim is t0, and the throttle opening pct ThrActOff0 and the atmospheric pressure at the time when the engine enters the shutdown working condition and the engine speed does not exceed a preset value (30 rpm in this example) are recorded; where r ThrBfActLim is a preset value, which is 0.05 in this example; the preset time learning correction coefficient r Delay is updated as shown in the following three cases:

[0120] First case: if the throttle opening pct ThrActOff0 at the time when the engine enters the shutdown working condition and the engine speed does not exceed a preset value is greater than 9%, and the difference between the atmospheric pressure corresponding to the last update of the preset time learning correction coefficient r Delay and the current atmospheric pressure exceeds a preset value (±3 kPa in this example), then only the preset time learning correction coefficient rDelay , other throttle opening degrees are not updated, preset time learning correction coefficient r is updated according to the following formula: Delay , where r(z) is preset time learning correction coefficient updated last time, k1 is weighting coefficient, and the value of k1 is 0.01 in the present example; if the throttle opening degree pct(z) of the engine at the moment when the engine enters the stop working condition and the engine speed does not exceed the preset value is greater than 9%, and the difference between the atmospheric pressure corresponding to the preset time learning correction coefficient updated last time and the current atmospheric pressure does not exceed the preset value, preset time learning correction coefficient r is not updated this time. Delay ThrActOff0 Delay Delay

[0121] The second case: if the throttle opening degree pct(z) of the engine at the moment when the engine enters the stop working condition and the engine speed does not exceed the preset value is one of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, and 9%, and the difference between the atmospheric pressure corresponding to the preset time learning correction coefficient updated last time and the current atmospheric pressure exceeds the preset value (±3 kPa in the present example), preset time learning correction coefficient r is updated only at the corresponding throttle opening degree, and preset time learning correction coefficient r is not updated at other throttle opening degrees. ThrActOff0 Delay Delay Delay Delay , where r(z) is preset time learning correction coefficient updated last time, k1 is weighting coefficient, and the value of k1 is 0.01 in the present example; if the difference between the atmospheric pressure corresponding to the preset time learning correction coefficient updated last time and the current atmospheric pressure does not exceed the preset value, preset time learning correction coefficient r is not updated this time. Delay Delay Delay

[0122] The third case: if the throttle opening degree pct(z) of the engine at the moment when the engine enters the stop working condition and the engine speed does not exceed the preset value is between two adjacent values of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, and 9%, and the difference between the atmospheric pressure corresponding to the preset time learning correction coefficient updated last time and the current atmospheric pressure exceeds the preset value (±3 kPa in the present example), preset time learning correction coefficient r is updated only at the corresponding throttle opening degree, and preset time learning correction coefficient r is not updated at other throttle opening degrees. ThrActOff0 Delay Delay Delay ​​​​​​​​​​​​​​​​​Delay If the difference between the corresponding atmospheric pressure at the time of updating and the current atmospheric pressure is not more than a preset value, the preset time learning correction coefficient r of the current throttle opening degree is not updated Delay The corresponding throttle opening degree region is determined as follows: assuming that the engine enters the stop working condition and the engine speed is not more than a preset value at the time of throttle opening degree pct ThrActOff0 Between throttle opening degrees A and B, wherein A and B are a pair of adjacent values in 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 9%, if the preset time t EngMovingDelay of the throttle opening degree A read before the current updating is t A , the preset time t EngMovingDelay of the throttle opening degree B read before the current updating is t B , the preset time learning correction coefficient r ThrActOff corresponding to the throttle opening degree pct Delay is represented by r Delay (pct ThrActOff ), then:

[0123] Wherein r Delay (pct ThrActOff )(z) is the preset time learning correction coefficient of the throttle opening degree pct ThrActOff updated by the last self-learning, k2 is a weighting coefficient, and in the example, 0.01 is taken; the preset time learning correction coefficients of the throttle opening degrees A and B are updated, and are respectively represented by r Delay (A) and r Delay (B):

[0124]

[0125] Wherein k3 and k4 are preset weighting coefficients, and in the example, k3 is taken as 0.85 and k4 is taken as 0.85.

[0126] In the embodiment, the second method is:

[0127] The engine speed is filtered to obtain a filtered engine speed;

[0128] The throttle inlet pressure signals are read for a plurality of times, and the estimated value of the throttle inlet pressure signal in the next sampling period is estimated according to the throttle inlet pressure signal;

[0129] The sampling number for checking the throttle inlet pressure signal is determined;

[0130] Whether the throttle inlet pressure signal is faulty is judged according to the filtered engine speed, the estimated value of the throttle inlet pressure signal and the sampling number.

[0131] Specifically, in the second method:

[0132] The filtered engine speed n Filt is calculated as follows: the raw real-time engine speed n Filt read by the sensor in the current sampling period n Filt (m) and the filtered engine speed n Raw in the next sampling period n Filt (m+1) are related as follows:

[0133] n Raw (m+1) = k x n Filt (m) + (1-k) x n Filt (m);

[0134] where m = 0, 1, 2,..., and in particular n ThrBfAct (0) = 0; k is the filter coefficient, which is taken as 0.2 in this example;

[0135] The method for estimating the predicted value of the throttle inlet pressure signal in the next sampling period from the throttle inlet pressure signal is as follows: the latest continuous 9 throttle inlet pressure signals are read in real time to form an array [p ThrBfAct (0), p ThrBfAct (N-1)…], where p ThrBfAct (0) is the throttle inlet pressure signal read in the current sampling period, p ThrBfAct (N-1) is the throttle inlet pressure signal read in the previous N-1 sampling periods, and so on to obtain the throttle inlet pressure signal p ThrBfAct (k) in the previous k sampling periods, k = 0, 1, 2,..., N-1; and the predicted value p ThrBfAct (k-1)' of the throttle inlet pressure signal in the previous k-1 sampling periods is estimated as follows:

[0136]

[0137] where k = 0, the predicted value p ThrBfAct (k+1)' of the next throttle inlet pressure signal = p ThrBfAct (1)' = 0 (kPa / s); the rate of change of the throttle inlet pressure signal in the previous k sampling periods is: where k = 0, Δp ThrBfAct (k) = Δp ThrBfAct (0) = 0 (kPa / s), p ThrBfAct (k+1)' = p ThrBfAct (1)' = 0 (kPa / s); Δt is the sampling period, which is taken as 10 ms in this example; and tc The filter time period for pressure estimation is 30 ms in this example.

[0138] The method for determining the sampling number V for the throttle inlet pressure signal verification is as follows: the value of is calculated according to the filtered engine speed n Filt and the original real-time engine speed n Raw ; wherein When the value is 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.28, 0.3, or 0.32, the sampling number V corresponds to the values 1, 1, 2, 2, 3, 4, 4, 5, or 6, respectively. When the value of is between two adjacent values in 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.28, 0.3, or 0.32, the sampling number V takes the value of the sampling number V corresponding to the larger of the two adjacent values. The control table of and the sampling number V is as follows:

[0139]

[0140] The larger the value is, the greater the engine speed fluctuation is, and more sampling number of pressure signals are needed to determine whether the throttle inlet pressure signal is faulty.

[0141] The method for determining whether the throttle inlet pressure signal is faulty according to the filtered engine speed, the estimated value of the throttle inlet pressure signal, and the sampling number is as follows:

[0142] When the throttle inlet pressure judgment condition is met, the estimated value of the throttle inlet pressure signal p ThrBfAct (V-1) of the current sampling period for V times is obtained. ThrBfAct (V-1) is obtained.

[0143] In this embodiment, the throttle inlet pressure judgment condition is as follows:

[0144] (1) The actual engine intake density fluctuation does not exceed a preset value; too large fluctuation leads to reduced detection accuracy; through testing verification, the actual engine intake density fluctuation does not exceed ±50 mg / l / 10 ms in this embodiment.

[0145] (2) The throttle opening fluctuation does not exceed a preset value; too large fluctuation leads to reduced detection accuracy; through testing verification, the throttle opening fluctuation does not exceed ±5% / 10 ms in this embodiment.

[0146] (3) The engine running time in this engine driving cycle exceeds a preset time, which is 30 min in this example. ​

[0147] The effectiveness judgment can be made only after the above conditions are met simultaneously:

[0148] When V = 1, if |p ThrBfAct (0)'-p ThrBfAct (0) | is greater than a preset value C1 (5 kPa in this example), it is judged that the throttle inlet pressure signal has a preliminary fault, otherwise it is judged that the throttle inlet pressure signal has no preliminary fault; wherein the preset value C1 = 5 x (1 + r Lrn ), r Lrn is a self-learning correction coefficient of the preset value C1, and its default value is 0, which can be saved after the vehicle is powered off;

[0149] When V = 2, if |p ThrBfAct (0)'-p ThrBfAct (0) |, |p ThrBfAct (1)'-p ThrBfAct (1) | are all greater than the preset value C1, it is judged that the throttle inlet pressure signal has a preliminary fault, otherwise it is judged that the throttle inlet pressure signal has no preliminary fault;

[0150] When V = 3, if |p ThrBfAct (0)'-p ThrBfAct (0) |, |p ThrBfAct (1)'-p ThrBfAct (1) |, |p ThrBfAct (2)'-p ThrBfAct (2) | are all greater than the preset value C1, it is judged that the throttle inlet pressure signal has a preliminary fault, otherwise it is judged that the throttle inlet pressure signal has no preliminary fault;

[0151] When V = 4, if |p ThrBfAct (0)'-p ThrBfAct (0) |, |p ThrBfAct (1)'-p ThrBfAct (1) |, |p ThrBfAct (2)'-p ThrBfAct (2) |, |p ThrBfAct (3)'-p ThrBfAct (3) | are all greater than the preset value C1, it is judged that the throttle inlet pressure signal has a preliminary fault, otherwise it is judged that the throttle inlet pressure signal has no preliminary fault;

[0152] When V = 5, if |p ThrBfAct (0)'-p ThrBfAct (0) |, |p ThrBfAct (1)'-p ThrBfAct (1) |, |p ThrBfAct (2)'-p ThrBfAct (2) |, |p ThrBfAct(3) |p ThrBfAct (3) |p ThrBfAct (4) |p ThrBfAct If |p

[0153] If |p ThrBfAct (0) |p ThrBfAct (0) |p ThrBfAct (1) |p ThrBfAct (1) |p ThrBfAct (2) |p ThrBfAct (2) |p ThrBfAct (3) |p ThrBfAct (3) |p ThrBfAct (4) |p ThrBfAct (4) |p ThrBfAct (5) |p ThrBfAct If |p

[0154] The self-learning correction coefficient r Lrn of the preset value C1 is updated as follows: record the effective number CNT1 of times when the throttle inlet pressure signal is judged not to have a preliminary fault and the ineffective number CNT2 of times when the throttle inlet pressure signal is judged to have a preliminary fault under different sampling numbers V, wherein CNT1 and CNT2 are updated at most once per vehicle driving cycle: if CNT1≥160 and CNT2≤10, then r Lrn (z) = r Lrn (z) - 0.005; if CNT1≤10 and CNT2≥160, then r Lrn (z) = r Lrn (z) + 0.012; and in other cases, r Lrn (z) = r Lrn (z); wherein r L rn(z) is the self-learning correction coefficient of the preset value C1 updated last time.

[0155] If CNT1+CNT2>200, CNT1180, and then the throttle inlet pressure signal is judged to have a fault, otherwise the throttle inlet pressure signal is judged not to have a fault; and when the throttle inlet pressure signal is judged to have a fault, CNT1 and CNT2 are cleared, and the counting is restarted when the conditions are met next time.

[0156] In this embodiment, the third method is:

[0157] When the judgment condition of the steady working condition of the throttle inlet pressure is met, the average value of the throttle inlet pressure and the average value of the throttle outlet pressure in a preset time are obtained;

[0158] According to the average value of the throttle inlet pressure, the average value of the throttle outlet pressure and the self-learning correction coefficient, it is judged whether the throttle inlet pressure signal is faulty.

[0159] Specifically, the third method is specifically:

[0160] When the judgment condition of the steady working condition of the throttle inlet pressure is met, the average value of the throttle inlet pressure in a preset time t3 (2s in this example) is obtained and the average value of the throttle outlet pressure

[0161] If , it is judged whether the throttle inlet pressure signal is faulty, otherwise it is judged that the throttle inlet pressure signal is not faulty; wherein r Adpt is a self-learning correction coefficient, and the default value is 0, which can be saved when the vehicle is powered off;

[0162] The self-learning correction coefficient r Adpt is obtained as follows: record the number CNT3 of times that meet the judgment condition of the steady working condition of the throttle inlet pressure, record the number CNT4 of times that meet the judgment condition of the steady working condition of the throttle inlet pressure , record the number CNT5 of times that meet the judgment condition of the steady working condition of the throttle inlet pressure , and CNT3, CNT4 and CNT5 are updated at most once per driving cycle of the vehicle;

[0163] If CNT3≥200, CNT4≥160, and CNT5≤10, then r Adpt =r Adpt (z)-0.01;

[0164] If CNT3≥200, CNT4≤10, and CNT5≥130, then r Adpt =r Adpt (z)+0.015;

[0165] In other cases, r Adpt =r Adpt (z);

[0166] Wherein r Adpt (z) is the self-learning correction coefficient updated last time; when CNT3≥200, CNT3, CNT4 and CNT5 are reset to 0 after the self-learning correction coefficient r Adpt is updated, until the next condition is met to start counting again.

[0167] In this embodiment, the condition for determining stable throttle inlet pressure is as follows:

[0168] (1) The engine is running;

[0169] (2) The target air intake volume is stable;

[0170] rho DesFilter (N)=K Rho ×[rho DesRaw (N)-rho DesFilter (N-1)]+rho DesFilter (N-1); where rho DesRaw For the target intake volume, rho DesRaw (N) represents the target intake volume in the Nth sampling period, rho DesFilter The target intake volume after first-order low-pass filtering, rho DesFilter (N) represents the filtered target intake volume in the Nth sampling period, rho DesFilter (N-1) represents the filtered target intake volume for the (N-1)th sampling period, where N = 1, 2, 3, ..., rho DesFilter (0) equals the target intake volume rho at the 0th sampling period. DesRaw (0); Sampling period interval Δt, which is 10ms in this example. K Rho For coefficients: (This example k) Rho The calibration speed is 1000 rpm. The purpose of this setting is for normalization; at different speeds, no special calibration is needed, only k at 1000 rpm. Rho (thus reducing calibration testing work), where n is the engine speed, k Rho This is the gas flow filtering coefficient; in this example, it is set to 0.02.

[0171] In |rho DesRaw (N)-rho DesFilter (N)| <min[rho DesRaw (N), rho DesFilter (N)]×r RhoLim The condition is met continuously for a time T. Rho This indicates that the target intake air volume is in a stable state (with minimal air volume fluctuations). Wherein, r RhoLim In this example, T is taken as 0.05. Rho This example uses 0.4s.

[0172] (3) The actual intake pressure at the throttle outlet is stable;

[0173] p ManFilter (N)=KMan ×[p Man (N)-p ManFilter [(N-1)]+p ManFilter (N-1); where p Man p is the intake pressure at the throttle outlet. Man (N) represents the throttle outlet intake pressure during the Nth sampling period, p ManFilter p is the throttle outlet intake pressure after first-order low-pass filtering. ManFilter (N) represents the filtered throttle outlet intake pressure during the Nth sampling period, p ManFilter (N-1) represents the filtered throttle outlet intake pressure during the (N-1)th sampling period, where N = 1, 2, 3, ..., p ManFilter (0) equals the throttle outlet intake pressure p during the 0th sampling period. Man (0); The sampling period interval Δt is 10ms in this example. K Man For coefficients: (This example k) Man The calibration speed is 1000 rpm. The purpose of this setting is for normalization; at different engine speeds, no special calibration is needed, only calibration of the 4-cylinder engine and the k-type engine at 1000 rpm. Man (thus reducing calibration testing work), where n is the engine speed, k Man This is the throttle outlet intake pressure filtering coefficient; in this example, it is set to 0.02.

[0174] In |p Man (N)-p ManFilter (N)| <min[p Man (N), p ManFilter (N)]×r ManLim The condition is met continuously for a time T. Man This indicates that the intake pressure is in a stable state (with minimal intake pressure fluctuations). Wherein, r ManLim In this example, T is taken as 0.05. Man This example uses 0.4s.

[0175] (4) The engine speed fluctuation does not exceed the preset range, which is ±15 rpm in this example;

[0176] (5) The opening degree of the booster actuator is equal to its full opening degree, which is the opening degree corresponding to the maximum booster capacity of the booster.

[0177] (6) Throttle opening is greater than the preset value, which is 95% in this example;

[0178] (7) No fault was detected in the throttle outlet pressure signal;

[0179] (8) the product of the 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); wherein the short-term fuel correction can be obtained from the patent with the publication number CN113847155A, and the long-term fuel correction can be obtained from the patent with the publication number CN111412074A. If the product of the short-term fuel correction and the long-term fuel correction is small, it indicates that the difference between the requested fuel injection amount and the actual fuel injection amount is small, the accuracy of the requested fuel injection amount calculated based on the intake air amount is high, the accuracy of the engine intake air amount is high, and the throttle inlet pressure sensor signal is accurate.

[0180] S2, judging whether the throttle inlet pressure signal is faulty according to the results of the first method, the second method, and the third method.

[0181] Specifically, in this embodiment, the method for judging whether the throttle inlet pressure signal is faulty according to the results of the first method, the second method, and the third method is as follows:

[0182] If only the second method judges that the throttle inlet pressure signal is faulty in the current driving cycle, but the first method and the third method both judge that the throttle inlet pressure signal is not faulty, it is finally judged that the throttle inlet pressure signal is not faulty, and the self-learning correction coefficient r Lrn = r Lrn (z) + 0.3, the self-learning correction coefficient r Adpt = r Adpt (z) - 0.005.

[0183] If only the second method judges that the throttle inlet pressure signal is not faulty in the current driving cycle, but the first method and the third method both judge that the throttle inlet pressure signal is faulty, it is finally judged that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r Lrn = r Lrn (z) - 0.2, the self-learning correction coefficient r Adpt = r Adpt (z) + 0.002.

[0184] If only the third method judges that the throttle inlet pressure signal is faulty in the current driving cycle, but the first method and the second method both judge that the throttle inlet pressure signal is not faulty, it is finally judged that the throttle inlet pressure signal is faulty, and the self-learning correction coefficient r Lrn = r Lrn (z) + 0.3, the self-learning correction coefficient r Adpt = rAdpt (z) + 0.008;

[0185] If the throttle inlet pressure signal is judged to be faulty by the second method and the third method in the current driving cycle, but is judged to be not faulty by the first method, the throttle inlet pressure signal is finally judged to be faulty, and the self-learning correction coefficient r of the preset value C1 Lrn = r Lrn (z) - 0.2, the self-learning correction coefficient r of the preset value C1 Adpt = r Adpt (z) - 0.01;

[0186] If the throttle inlet pressure signal is judged to be faulty by the second method and the third method in the current driving cycle, but is judged to be not faulty by the first method, the throttle inlet pressure signal is finally judged to be faulty, and the self-learning correction coefficient r of the preset value C1 Lrn = r Lrn (z) - 0.01, the self-learning correction coefficient r of the preset value C1 Adpt = r Adpt (z) - 0.01;

[0187] If the throttle inlet pressure signal is judged to be faulty by the second method and the third method in the current driving cycle, but is judged to be not faulty by the first method, the throttle inlet pressure signal is finally judged to be faulty, and the self-learning correction coefficient r of the preset value C1 Lrn = r Lrn (z) + 0.02, the self-learning correction coefficient r of the preset value C1

[0188] r Adpt = r Adpt (z) + 0.008;

[0189] If the throttle inlet pressure signal is judged to be faulty by the second method, the third method and the first method in the current driving cycle, the throttle inlet pressure signal is finally judged to be faulty, and the self-learning correction coefficient r of the preset value C1 Lrn = r Lrn (z), the self-learning correction coefficient r of the preset value C1 Adpt = r Adpt (z);

[0190] In other cases, the throttle inlet pressure signal is finally judged to be not faulty, and the self-learning correction coefficient r of the preset value C1 Lrn = r Lrn (z), the self-learning correction coefficient r of the preset value C1 Adpt = r Adpt (z).

[0191] In summary, the present application provides a throttle inlet pressure signal checking method, which can check the rationality of the pressure signal of the pressure sensor before the throttle.

[0192] It should be noted that, according to the needs of implementation, each step described in the present application can be split into more steps, or two or more steps or part of the operation of the step can be combined into a new step to achieve the purpose of the present application.

[0193] Those skilled in the art will easily understand that the above description is only a preferred embodiment of the present application and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for verifying throttle inlet pressure signal, characterized in that, include: The throttle inlet pressure signal was checked using the first method, the second method, and the third method, respectively. Determine whether the throttle inlet pressure signal is faulty based on the results of the first method, the second method, and the third method. The first method is: when the throttle pressure verification conditions are met, read the throttle inlet pressure signal and the throttle outlet pressure signal in real time; Based on the throttle inlet pressure signal, the throttle outlet pressure signal, and a preset time, determine whether the throttle inlet pressure signal is faulty; The second method is to filter the engine speed to obtain the filtered engine speed; Read several consecutive throttle inlet pressure signals, and estimate the value of the throttle inlet pressure signal in the next sampling cycle based on a certain throttle inlet pressure signal; The number of samplings for throttle inlet pressure signal verification is determined based on the filtered engine speed and the original real-time engine speed. The throttle inlet pressure signal is judged to be faulty based on the number of samplings, the estimated value of the throttle inlet pressure signal, and the actual value of the throttle inlet pressure signal. The third method is: when the throttle inlet pressure is stable and the condition for judging the condition is met, obtain the average value of the throttle inlet pressure and the average value of the throttle outlet pressure within a preset time. Based on the average value of the throttle inlet pressure, the average value of the throttle outlet pressure, and the self-learning correction coefficient, it is determined whether the throttle inlet pressure signal is faulty.

2. The method for verifying the throttle inlet pressure signal according to claim 1, characterized in that, The first method specifically involves: when the throttle pressure check conditions are met, reading the throttle inlet pressure signal p in real time. ThrBfAct With the pressure signal p after the throttle valve ThrAftAct If the following occurs: 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 is not faulty.

3. The method for verifying the throttle inlet pressure signal according to claim 2, characterized in that, The throttle pressure verification conditions are as follows: (1) The time during which the engine speed does not exceed the preset value exceeds the preset time t. EngMovingDelay ; (2) Neither the atmospheric pressure sensor nor the throttle body pressure sensor malfunctioned; (3) The difference between the atmospheric pressure signal and the pressure signal after the throttle valve is within the preset range; (4) The fluctuations of atmospheric pressure signal and throttle body pressure signal do not exceed the preset range.

4. The method for verifying the throttle inlet pressure signal according to claim 3, characterized in that, The preset time t EngMovingDelay =t EngMovingDelayRaw ×(1+r Delay ), the t EngMovingDelayRaw The preset initial time value is r. Delay The learning correction coefficient is set at a preset time, with an initial value of 0. It is continuously learned and updated, and can be saved after the vehicle is powered off.

5. The method for verifying the throttle inlet pressure signal according to claim 4, characterized in that, The preset initial time value t EngMovingDelayRaw The throttle opening (pct) depends on the engine speed at which the preset value is not exceeded. ThrActOff When the throttle opening is pct ThrActOff When the values ​​are 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, and 9%, the preset initial time value t is... EngMovingDelayRaw The corresponding values ​​are 12000ms, 10000ms, 6000ms, 4000ms, 2000ms, 1200ms, 1000ms, 500ms, and 500ms.

6. The method for verifying the throttle inlet pressure signal according to claim 5, characterized in that, The preset time learning correction coefficient r Delay The method for obtaining it is as follows: When the first method determines that the throttle inlet pressure signal is not faulty, the throttle inlet pressure signal is recorded starting when the engine enters a shutdown state and the engine speed does not exceed a preset value, and the throttle inlet pressure signal is filtered: p ThrBfActFilter (N)=K ThrBf ×[p ThrBfAct (N)-p ThrBfActFilter [(N-1)]+p ThrBfActFilter (N-1); where p ThrBfAct p is the throttle inlet pressure. ThrBfAct (N) represents the throttle inlet pressure during the Nth sampling period, p ThrBfActFilter p is the throttle inlet pressure after first-order low-pass filtering. ThrBfActFilter (N) represents the filtered throttle inlet pressure during the Nth sampling period, p ThrBfActFilter (N-1) represents the filtered throttle inlet pressure during the (N-1)th sampling period, where N = 1, 2, 3, ..., p ThrBfActFilter (0) equals 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 condition and the engine speed does not exceed the preset value, and the sampling period interval is Δt; K ThrBf These are the filter coefficients; Record the time from when the engine enters the shutdown condition and the engine speed does not exceed the preset value until the occurrence of |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 at the moment when the engine enters the shutdown condition and the engine speed does not exceed the preset value. ThrActOff0 and atmospheric pressure; where r ThrBfActLim The preset value is used; the preset time learning correction coefficient r is set to... Delay The update methods are as follows: First scenario: If the engine enters a shutdown state and the engine speed does not exceed the preset throttle opening value (pct) at that time. ThrActOff0 When it is greater than 9%, and the previous preset time learning correction coefficient r Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure exceeds a preset value, then only the preset time learning correction coefficient r at a throttle opening of 9% will be updated. Delay The preset time learning correction coefficient r is not updated at other throttle openings. Delay The update calculation formula is: Where, r Delay (z) represents the preset time learning correction coefficient of the last self-learning update, and k1 is the weighting coefficient; if the engine enters the shutdown condition and the engine speed does not exceed the preset value of the throttle opening pct at that time. ThrActOff0 When it is greater than 9%, and the previous preset time learning correction coefficient r Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure does not exceed a preset value, then the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ; Second scenario: If the engine enters a shutdown state and the engine speed does not exceed the preset throttle opening value (pct) at that time. ThrActOff0 The value can be one of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, or 9%, if the previous preset time learning correction coefficient r Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure exceeds a preset value, then only the preset time learning correction coefficient r at 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: Where, r Delay (z) represents the preset time learning correction coefficient from the previous self-learning update, and k1 is the weighting coefficient; if the preset time learning correction coefficient r Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure does not exceed a preset value, then the preset time learning correction coefficient r under any throttle opening will not be updated this time. Delay ; Third scenario: If the engine enters a shutdown state and the engine speed does not exceed the preset throttle opening value (pct) at that time. ThrActOff0 The value is located between two adjacent values ​​in the range of 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, and 9%. If the previous preset time learning correction coefficient r... Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure exceeds a preset value, then only the preset time learning correction coefficient r for 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 learning correction coefficient r for the previous preset time is... Delay If the difference between the atmospheric pressure at the time of update and the current atmospheric pressure does not exceed a preset value, then 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 range is as follows: Assuming the engine enters a shutdown state and the engine speed does not exceed a preset value, the throttle opening is pct at that moment. ThrActOff0 Between throttle openings A and B, where A and B are a pair of adjacent values ​​from 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, and 9%, if the preset time t corresponding to the throttle opening A read before this update... EngMovingDelay For t A The preset time t corresponding to the throttle opening B read before this update EngMovingDelay For t B Determine the throttle opening pct ThrActOff The corresponding preset time learning correction coefficient r Delay Use r Delay (pct ThrActOff If ) indicates that: Where r Delay (pct ThrActOff (z) represents the throttle opening value updated during the last self-learning process, which is pct. ThrActOff The preset time learning correction coefficient is set below, and k2 is the weighting coefficient; simultaneously, the preset time learning correction coefficients for throttle opening A and throttle opening B are updated, respectively using r Delay (A) and r Delay (B) indicates: Where k3 and k4 are preset weighting coefficients.

7. The method for verifying the throttle inlet pressure signal according to claim 6, characterized in that, In the second method: Obtain the filtered engine speed n Filt The calculation method is as follows: the wave engine speed n in this sampling period Filt (m) and the filtered engine speed n in the next sampling period Filt (m+1) and the raw, real-time engine speed n read from the sensor. Raw Establish the following relationship: n Filt (m+1)=k×n Raw +(1-k)×n Filt (m); Where m = 0, 1, 2, ..., n Filt (0) is set to 0; k is the filter coefficient.

8. The method for verifying the throttle inlet pressure signal according to claim 7, characterized in that, The third method is specifically as follows: When the throttle inlet pressure stability condition is met, the average throttle inlet pressure within a preset time t3 is obtained. Average throttle outlet pressure like If the throttle inlet pressure signal is faulty, it is determined that the throttle inlet pressure signal is not faulty; otherwise, it is determined that the throttle inlet pressure signal is not faulty. Wherein r Adpt This is the self-learning correction factor, with a default value of 0, which can be saved when the vehicle is powered off.

9. The method for verifying the throttle inlet pressure signal according to claim 8, characterized in that, The self-learning correction coefficient r Adpt The method for obtaining the value is as follows: Record the number of times (CNT3) the throttle inlet pressure stabilization condition judgment condition is met, and record the number of times (CNT3) the throttle inlet pressure stabilization condition judgment condition is met. The number of times CNT4 is recorded, and the condition for judging stable throttle inlet pressure is satisfied is recorded. The number of times CNT5 is updated, and 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) represents the self-learning correction coefficient from the last update; when CNT3 ≥ 200, then the self-learning correction coefficient r Adpt After the update is complete, CNT3, CNT4 and CNT5 will all be reset to 0, and the counting will restart when the next condition is met.

10. The method for verifying the throttle inlet pressure signal according to claim 1, characterized in that, The condition for determining stable throttle inlet pressure is as follows: (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) Engine speed fluctuations do not exceed the preset range; (5) The opening degree of the booster actuator is equal to its full opening degree; the full opening degree is the opening degree corresponding to the maximum boosting capacity of the booster. (6) Throttle opening is greater than the preset value; (7) No fault was detected in the throttle outlet pressure signal; (8) The product of the engine's short-term fuel trim and long-term fuel trim is within the preset range and exceeds the preset time.

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