JP2000282931A - Control method and apparatus for internal combustion engine - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To maintain a desired rotation speed limit without shutting off fuel supply, and to ensure the operation of internal combustion engine control even in the case of an error. A method and a device for controlling an internal combustion engine, wherein the torque of the internal combustion engine is set as a function desired by a driver, and the rotational speed of the internal combustion engine is measured and limited to a predetermined value. For this purpose, a rotation speed limit controller that limits the engine rotation speed to a predetermined monitor rotation speed is used.The limit controller first controls the air supply and the internal combustion engine so as to limit the engine rotation speed to the monitor rotation speed. And / or reducing the torque by ignition and / or engagement with the fuel supply to completely refuel at least one cylinder of the internal combustion engine when at least one particular error case exists. Cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for controlling an internal combustion engine.

[0002]

From DE 195 36 038 A, in order to ensure the reliability of the operation of the internal combustion engine control, the maximum permissible torque of the internal combustion engine is formed at least on the basis of the position of the operating element which can be operated by the driver. Control methods and devices for internal combustion engines are known. This maximum allowable torque is compared with the actual torque of the internal combustion engine. If the actual torque exceeds the maximum allowable torque, an error condition of the control is inferred and measures are taken for an error response until the actual torque again falls below the maximum allowable torque. This torque
Monitoring is significantly affected by the actual torque measurement accuracy. Therefore, in order to improve the certainty of monitoring in the operation of the internal combustion engine control, September 24, 1997
In the unpublished German Patent Application No. 19742083.4, the torque monitoring is interrupted when an error is presumed in the range of the torque measurement or of the filling measurement on which it is based (air mass flow measurement). Was added. To ensure the reliability of operation,
When the engine speed exceeds a predetermined engine speed at a predetermined position of the accelerator pedal, fuel supply to the internal combustion engine is cut off.

[0003] In these methods, when a predetermined engine speed is exceeded, even if there is no error in the control range of the internal combustion engine, a fuel cutoff is generally performed to ensure operation reliability. However, in some embodiments, it is desirable to suppress fuel cutoff under certain conditions, for example, when heating the catalyst, when increasing the catalyst temperature to protect the catalyst, and the like. , This method is unacceptable. Nevertheless, in the case of an error, it is desirable not to exceed the speed limit when the accelerator pedal is released.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to maintain the desired rotational speed limit without interrupting the fuel supply and to ensure the reliability of the operation of the internal combustion engine control in the event of an error.

[0005]

According to the present invention, the torque of the internal combustion engine is set as a function desired by the driver, whereby the rotational speed of the internal combustion engine is measured and limited to a predetermined value. In a control method and apparatus for an internal combustion engine,
In order to limit the engine speed, a speed limit controller that limits the engine speed to a predetermined monitor speed is used, and the speed limit controller first limits the engine speed to the monitor speed. Thus, the torque is reduced by engagement of the internal combustion engine with the air supply and / or ignition and / or fuel supply and, additionally, when at least one predetermined error condition exists, at least one of the internal combustion engine The fuel supply to the three cylinders is completely shut off.

[0006] From DE-A 42 32 711,
An example of how the target torque value is converted into a charge of the internal combustion engine, into a control variable for adjusting the ignition angle and / or into the number of cylinders to be shut off is known.

[0007] The engine speed is limited to a safe speed in at least one predetermined operating state, and in a normal state in which there is no interruption of fuel supply and no error information is present, the charge amount engagement and the ignition angle control are performed. And / or limited by engagement with the fuel supply. In addition, when certain peripheral conditions exist, in particular when an error characteristic exists in the control device or in the components connected to the control device that cause an undesired increase in the rotational speed, at least the individual cylinders The cutoff of the fuel supply to the vehicle is allowed. As a result, in normal operation, it is possible to maintain a function that does not shut off the fuel supply despite the limitation to the safe rotation speed, while, when an error is detected, Possible fuel cut-off ensures certainty. Furthermore, it is not necessary to determine whether the increase in rotational speed is due to an error.

[0008] It is advantageous that non-detectable errors that can lead to increased rotational speed can also be suppressed without shutting off the fuel supply.

Advantageously, the availability of the device is improved by not interrupting the fuel supply even when the safe rotational speed threshold is reached.

[0010] In particular, the combination of the engine speed limiting means according to the invention when the accelerator pedal is released and the torque comparison for monitoring internal combustion engine control described at the outset is particularly advantageous. The combination of both means constitutes a very reliable and complete monitoring means covering all operating conditions.

If a torque comparison is not used, it is advantageous that a significant reduction in adaptation costs is achieved, for example because the maximum allowable torque does not have to be set.

The limitation of the rotational speed according to the method described below is advantageous in that it improves ride comfort in the event of an error, since the vehicle response is essentially slow, unlike the vehicle response which initiates a fuel cut-off. is there. This is due to the fact that the rotational speed is initially kept low via torque reduction due to charge and / or ignition angle. This causes the rotation speed to rise very rapidly beyond the limit,
Then, abrupt limitation due to cutoff of the injection is avoided. Such a control would result in sudden movements that would be uncomfortable for the driver.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS In the following, the invention is explained in more detail by means of an embodiment for an example having a filling quantity engagement and an ignition angle engagement as shown in the drawings.

FIG. 1 shows an electronic control unit 10,
The control unit 10 comprises at least one input circuit 12,
At least one microcomputer 14 and at least one output circuit 16 are provided. Input circuit 1
2, microcomputer 14, and output circuit 16
Are interconnected via a communication system 18 for data exchange between them. The input circuit 12 has the following input lines: an input line 20 from a measuring device 22 for measuring the accelerator pedal position wped, an input line 24 from a measuring device 26 for measuring the throttle valve position wdk, an internal combustion engine. Input line 28 from a measuring device 30 for measuring the air mass flow rate hfm supplied to the engine speed n
An input line 32 from a measuring device 34 for measuring mot and other operating variables of the internal combustion engine and / or the vehicle, such as, for example, intake air temperature, atmospheric pressure, etc., required for performing engine control are measured. Input lines 36 to 40 from measuring devices 42 to 46 are provided. Via the output circuit 16, the electronic control unit 10
Controls the output parameters of the internal combustion engine. Thus, the charge of the internal combustion engine is controlled by adjusting the air supply of the internal combustion engine via the throttle valve 48. In addition, the ignition point is set (50), the fuel supply is adjusted (52), and / or the turbocharger (5).
4) is controlled.

The basic function of the engine control performed by the control unit 10 is known from the state of the art described at the outset.
Based on at least the accelerator pedal position wped, a target value for the torque of the internal combustion engine, which corresponds to the driver's wishes, is determined. The driver's wishes are converted into torque target values, possibly taking into account other target torques from external and internal functions such as drive slip control, rotational speed limiting, speed limiting and the like. This torque target value is then taken into account in a corresponding characteristic curve group, table or calculation step, taking into account at least the engine speed, the cylinder value normalized by the target value for the charge, ie the maximum possible cylinder charge. It is converted to a target value for the relative air charge per stroke. As a function of this target charge value, the target throttle valve position value is determined while taking into account the physical relationship in the intake pipe. Next, it is controlled to a target value by a corresponding control circuit. Furthermore, the ignition angle and / or the fuel supply are optionally adjusted, for example taking into account the actual torque calculated on the basis of the air mass flow signal, in which case the actual torque is controlled to the target torque. Furthermore, in one embodiment, in the event of an error, the control unit 10 performs a torque comparison as described at the outset using predetermined error response means.

In addition to, or in some embodiments, in place of, the torque comparison, a rotational speed limiting controller is used that reduces the target torque to a minimum allowable torque for combustion operation. This limits the engine speed to a predetermined monitor speed, which is a function of the accelerator pedal position or the driver's desired torque, for example. The minimum torque is set to zero when injection cutoff is allowed. If an error is detected within the control of the internal combustion engine or within the components connected thereto, injection cut-off is permitted.

The flowcharts of FIGS. 2-4 illustrate a preferred embodiment of the rotational speed limit controller. FIG. 2 shows a flowchart for the basic function of such a limiting controller, and FIG. 3 shows a flowchart for correcting the minimum torque value for the limiting controller. FIG. 4 is a flow chart showing the inspection of the injection start condition.

As is known, in a torque-oriented internal combustion engine control configuration, a driver desired target torque mifa is formed based on variables such as accelerator pedal position and engine speed (100). Driver's desired target torque mi
fa is combined with the loss or consumed torque miver,
It is preferably added (coupling stage 102), in which case the loss or consumed torque mover is formed as a function of variables such as engine speed, engine temperature or the state of the associated consumer (104). The target torque thus formed is corrected by the engagement of the idling rotational speed controller (coupling stage 106). This target value misol
l is then converted, as is known, into a target value rLsoll for the cylinder charge and a target value αz for the ignition angle as the target value misoll_res obtained by the rotational speed limiting controller described below. This is done within the scope of the calculation program 108,
The basic properties of 8 are known from the prior art described at the outset. Therefore, this program will not be described in detail. Similarly, the detailed illustration of the conversion (110) of the target charging value and the target ignition angle value into the actual control amounts (dK, dz, ti) by the program is omitted for clarity. An overview of this transformation is likewise known from the state of the art described at the outset. Unlike the prior art, the only difference is that when at least one condition B_eauew is present, the injection cut-off (EA), ie the cut-off of the individual cylinders, is simultaneously taken into account in the conversion of the setpoint torque value in the control variable. The start of the cut-off when the condition B_eauew exists is determined by the switching element 114
Is symbolized by.

This embodiment is shown for an engine control with λ = 1 operation. However, likewise,
This method can be used for a gasoline direct injection engine with a homogeneous combustion lean operation or a stratified combustion lean operation. In such an embodiment, the torque mi
Soll_res is further converted into an air-fuel ratio to be output and a fuel supply amount required for this.

The control output of the idle speed controller considered in the coupling stage 106 is formed as usual. In some cases, the target rotational speed nLLRsoll (characteristic curve group 116) set as a function of the operating variables is:
The measured actual rotational speed n to form the control deviation
ist. The control deviation is supplied to a controller 118, which preferably has a PID characteristic,
Generate an output signal that is a function of the control deviation. This output signal is limited by a limiter 120 to a maximum or minimum value and then combined (106, eg, summed) with the target torque. In this case, the idling rotational speed controller operates only when the idling operation state (B_llr) exists, that is, especially when the accelerator pedal is released and the throttle valve is closed. This is indicated by the switching element 122, which switches the condition B_
Closed when llr is present.

If the lost torque miver and / or the driver's desired torque mifa is erroneously calculated too high, the idling control can no longer set the target rotational speed due to the minimum limit. This error condition is not detected by the torque monitoring described at the outset. The restriction of the idling rotational speed control signal is used to prevent the engine from running away when the clutch is disengaged during normal operation.

The monitor rotational speed limiter also prevents an abnormal increase in the engine rotational speed, in particular, an increase exceeding a predetermined safe rotational speed of, for example, 1500 rpm in such an operating state. The monitor rotational speed limiter limits the engine rotational speed to a predetermined safe rotational speed NUEWB, which is fixedly set or variable, for example, as a function of accelerator pedal position (memory
Cell or characteristic curve group 124). The limiter forms a deviation between the current engine speed nist and the limit value NUEWB (coupling 126, preferably subtraction). Next, this deviation is a positive value (the rotation speed is above the safe rotation speed)
(Minimum limit to 128,0). The deviation is then fed to a controller 130, which in the preferred embodiment is designed as a PID controller. The output signal generated by the controller 130 as a function of the control deviation is output in a coupling stage 132 to the target torque value misol.
Change l. In a preferred embodiment, the output signal of the limiting controller is subtracted from the target torque value. This means that when the safe rotation speed is exceeded, the control engagement for reducing the target torque is performed.

[0023] Preferably, the monitor limit controller operates only in certain operating conditions. This is indicated by the switching element 134. In a preferred embodiment, the limit controller is activated only when the accelerator pedal is released. Correspondingly, the accelerator pedal position wp
ed is compared in a comparison stage 136 with a value indicating that the accelerator pedal is released, in which case the switching element is closed after a predetermined time TWUEB has elapsed since this operating state was first reached. (See delay element 138). When the vehicle leaves the operating state again, the integration characteristic of the monitor limit controller 130 does not operate. Therefore, when leaving this operating state, that is, when the pedal is operated, the limit controller is disconnected. In this case, this is indicated by detecting the negative slope of the signal of the comparison stage 136 at 140, as shown in FIG. Is derived by the control of By the steady return of the control output, that is, by the steady cancellation control of the integral part of the controller 130, a sudden change in torque is prevented because the gasoline supply is very small when the limiting controller is disconnected. The same applies when the controller is operating in a subrange of the range of the accelerator pedal position. Alternatively, the control part is reset abruptly when a load change damping function is used, starting from the total target torque present and constantly controlling the new desired torque without impact. This embodiment is not shown.

If the limit controller is operating over the entire accelerator pedal range, elements 134-140 are not required.

Unlike the idling rotation speed controller,
Since the monitor rotation speed limiter can reduce the torque at first without any limitation, the rotation speed can be reduced without limitation. When the rotational speed falls below the limit rotational speed, the control function becomes 0, so that the runaway of the engine when the clutch is disengaged is avoided.

Next, in the limiter 142, the target value adjusted by the monitor rotational speed limiter is possibly limited to the minimum value mn applied in normal operation. This minimum value is applied in such a way that combustion is still guaranteed even at the minimum charge and the ignition angle delayed as far as possible. In another embodiment, the minimum value of the torque is the minimum desired braking torque in coasting. The target torque reduced by the monitor rotational speed limiter, possibly limited to a minimum value, is then converted within the calculation program 108 into the corresponding charge value and ignition angle value.
In this way, in normal operation, at least in a certain operating state, a predetermined safe rotational speed is maintained, in which case, if this safe rotational speed is exceeded, the limiting control coupling is effected by a change in the charge and / or the ignition angle. Is performed.

The formation of the predetermined condition (B_eauew) is shown in FIG.
Indicates an error condition and a predetermined condition (B_eaue)
When w) is present, the minimum limiting torque of the limiter 142 is set to zero and the method for injection cutoff is started. In this case, in order to maintain the monitor rotation speed, the rotation speed limit controller can steadily reduce the torque to zero. Thus, the monitor limit controller ensures in all cases, even in the case of an error, that a safe rotational speed is maintained.

The minimum value mn of the limiter 142 is set to a value of 0 when there is a condition for starting injection cutoff. If this condition does not exist, the minimum is
At 4, a determination is made as a function of the engine speed, the engine target idle speed and the gear ratio input.
The relationship between this value and the minimum applies as described above. Switching between this calculated minimum and the minimum 0 is:
Symbolized by switching element 146, switching element 146
Is switched to 0 when the condition B_eawew exists. The minimum value formed in element 144 is combined in a combining stage 148, preferably a multiplication stage, by a factor fkm
Error cases weighted by imin and taking into account error cases in which the main load signal of the internal combustion engine control derived from the measured air mass flow signal or the intake pipe pressure signal are incorrectly set to low values by the factor fkminmin. . In such an error case, the charge is set to a low measured value, which corresponds to a very high actual value and will increase the rotational speed abnormally. In order to first detect and correct this first, the minimum value is reduced by the correction factor fkmmin.

FIG. 3 (FIG. 3a) shows one embodiment of the method by which this correction factor is formed. An incorrectly set main load signal in the lower value direction will have the same error tendency as the air mass flow integrator 202 and the multiplicative mixture correction factor Fra. In this case, the air mass flow rate integrated value is the air mass flow rate value mshfm determined based on the air mass flow rate sensor.
And the air mass flow rate msdk corrected from the integral value.
dk is calculated from the throttle valve opening angle and the pressure ratio between the intake pipe pressure and the atmospheric pressure (correction 204, deviation formation 200).
In this case, the multiplicative mixture correction factor Fra is essentially an output signal of the λ control. To determine the correction factor for the minimum torque, the minimum value of the deviation of the mixture correction factor Fra from 1 and the reversal integral value is used as the correction term.
The deviation of Fra from 1 is formed in element 207,
The inversion of the integral is formed at element 206. The neutral value and the deviation value thus formed are output to the minimum value selection stage 208.
Supplied to The smaller of both values is limited to a positive value (limiter 210), so that correction is allowed only in the direction of decreasing the minimum value (correction factor is less than or equal to 1). An error in the other direction, ie a false rise of the main load signal to a higher value, gives a smaller actual torque and thus does not limit the rotational speed limiter. The limited minimum is subtracted from 1 to form the correction factor fkmmin (combination stage 212).

Instead of reducing the minimum torque by a factor fkmmin, the actual charge signal is also divided by this factor and thus increased. When an air mass flow signal that is too low due to an error is assumed, the air mass flow signal is thereby corrected again to the correct value, and the rotational speed limiting control is likewise no longer restricted (see FIG. 3b).

As mentioned above, under certain conditions, in addition to the charge engagement and the ignition angle engagement for limiting the rotational speed and / or the engagement for reducing the fuel supply, the injection cutoff, ie the specific Shutdown of a number of cylinders is allowed for torque reduction. FIG. 4 shows a flowchart illustrating a preferred embodiment for determining the presence of this condition.

The first prerequisite is that a condition exists for the activation of the monitor speed limiter, ie, in the preferred embodiment, the accelerator pedal is released (wped threshold). Comparison 300). Further, it is a precondition that the engine speed is equal to or higher than the monitor speed NUEWB. This is performed by comparing a deviation between the engine speed and the monitor speed NUEWB, which is formed in the coupling stage 302, with a threshold value 304. Both of these conditions are combined with a logical AND (30
6), forming a condition signal B_uedb.

The actual filling signal rList is compared with the target filling signal rLsoll (see comparison stage 308), and the time gradient (drlist / dt) of the actual filling signal formed in the gradient forming stage 310 is passed through the low-pass filter 312. It is filtered and then compared in a comparison stage 314 with a predetermined limit value. Furthermore, the comparison stage 300
Waiting time (TW) after the occurrence of the operating state measured at
DP, delay 316) is taken into account. This signal (TWD
P) is an OR connection (V) 317 and an AND connection (&)
318. An output signal is output from the AND combination when the actual charge is greater than or equal to the target charge and the waiting time has elapsed or a large gradient of the actual torque is detected. The output signal of the AND connection 318 is combined with the operating state signal at an AND connection (&) 330 via an OR connection (V) 328, in which case a cutoff is allowed in the comparison of both signals. If an abrupt change due to an error is detected in the actual filling quantity, a corresponding control takes place immediately by shutting off the injection, which leads to a gradual error response of the vehicle in various error cases. Furthermore, if the actual filling amount is still greater than the target value after a certain period of time, the corresponding control is performed by shutting off the injection. Alternatively, the actual torque may be compared to the minimum torque.

A second independent path for allowing injection cutoff is an error in air mass flow measurement when conditions exist to activate the monitor limit controller. Air mass flow adjustment value fkmsd formed in FIG. 3a
k is subtracted from the value 1 (319), and its absolute value is formed in an absolute value forming stage 320 and compared to a limit value in a comparing stage 322. If air mass flow adjustment is allowed (see switching element 324), the comparison result is further processed. If the absolute value of the weighting correction coefficient is equal to or greater than the limit value (TWDSM) when this condition exists, the flip-flop 326 is set after a certain waiting time (325). This flip-flop is reset again when the ignition is turned on (S_k115), and is continuously set when an error occurs once. The output signal of flip flop 326 is combined at OR combination 328 with the signal formed at logical AND combination 318. Since the error is present in the air mass flow measurement when the adjustment factor exceeds the limit value, the cutoff of the injection is initiated for the limit when there is an operating condition for activating the limit control.

The output signal of the AND circuit 330 is a flip-flop.
Flip flop 332
Is set when the above condition occurs. Output signal of flip-flop 332 (B_eauewd)
Form a condition B_eauew for initiating the cutoff of the injection via the OR connection 334. After the flip-flop 332 is set, it is reset again by a new ignition (S_k115). Shutdown is allowed continuously for the operating cycle present.

In summary, when there is an operating range that exists for the execution of the monitor rotational speed limiting control, and the air mass flow adjustment with errors or the actual torque that is above the minimum and the very large actual torque gradients or waits If, after a lapse of time, an actual torque that is greater than or equal to a minimum value is detected, it can be said that injection cutoff is permitted.

Further, there is a condition that only temporarily permits injection cutoff. This is combined into a signal B_eauewv at the OR combination 336 and combined within the OR combination with the signal for the existence of a condition for continued allowance to form the allowance signal B_eauew. Vehicle speed V
When fzg is below a predetermined minimum threshold (see comparison stage 338), the error E_V in the vehicle speed measurement sensor
fzg, error E_hf in air mass flow measurement sensor
m, or an error E_dkg in the throttle valve sensor, a temporary injection cutoff is allowed.

In an example of a gasoline direct injection type engine whose torque is controlled by the fuel supply amount, which is not described in detail here, first, the injection time and the tank ventilation regeneration rate are controlled in order to control the rotational speed. When any of the above error cases is detected, the injection shutoff and the complete shutoff of the tank ventilation are likewise effected.

In a preferred embodiment, the monitor rotational speed limiter is activated in certain operating situations with the accelerator pedal released. In this operating state, the torque comparison described at the outset does not work. In the preferred embodiment, the torque comparison is active in all partial load ranges except for this operating condition. In another advantageous embodiment, especially in gasoline direct injection engines, the torque comparison is restricted to a range in which the pedal angle is close to zero.

The torque comparison control may be executed by the same microcomputer in the engine control device. in this case,
In an advantageous embodiment, the monitor rotational speed limiter comprises:
It is provided as a control function in another software channel. In an advantageous embodiment, the rotational speed limiting control is not performed on the basis of the crankshaft sensor, but on the basis of the phase sensor, whereby a pure dual channel between function and monitoring is achieved. .

In an advantageous embodiment, a method is used in which, even when the accelerator pedal is actuated, the monitor rotational speed is increased with the accelerator pedal position. In particular, in this case, the torque monitoring described at the beginning is not performed.

In a preferred embodiment, the second monitor rotational speed limit is performed by a redundant monitor computer or in a separate software path. Here, the rotational speed is preferably calculated based on the phase transmitter signal, while the first monitor rotational speed limiter operates based on a crankshaft sensor as rotational speed information. Thus, complete dual channel monitoring is performed.

Such a monitor rotational speed limiter is used not only in an intake pipe injection type gasoline internal combustion engine and a direct injection type gasoline internal combustion engine but also in a diesel engine.

In addition to the setting of the target torque, a target output or other output variables of the internal combustion engine are set.

If the limiter is operating in the entire operating range, the condition that there is an accelerator pedal released when allowing the shut-off is not necessary.

In another embodiment, the restrictor directly reduces the throttle valve angle and the ignition angle. The rotation speed limit control is
The torque of the internal combustion engine is reduced to a predetermined minimum value by reducing the amount of air supplied to the internal combustion engine to the minimum value and reducing the ignition angle to the predetermined delay angle. Furthermore, the adjusting element for adjusting the air supply may be completely closed in order to limit the engine speed to the monitor speed.

In direct-injection engines or lean-run engines, in order to reduce the torque by means of a rotational speed limiting controller, additionally or alternatively, the fuel supply is limited by the lean operating limit in homogeneous combustion operation. Or the combustible limit in stratified combustion operation.

The monitor rotation speed (safe rotation speed) is higher than the target idling rotation speed (preferably about 1500 rpm).

In another embodiment, instead of using the variables rLsoll and rList in FIG.
The values for the target torque misoll and the actual torque misist are evaluated accordingly.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of a control device for an internal combustion engine.

FIG. 2 is a flowchart showing the basic functions of the rotational speed limiting controller according to the present invention as a program of at least one microcomputer of the control device.

FIGS. 3a and 3b are flowcharts showing a method of determining a correction coefficient of a minimum torque value for a rotational speed limiting controller as a program of at least one microcomputer of the control device.

FIG. 4 is a flowchart showing an inspection of a start condition of injection cutoff as a program of at least one microcomputer of the control device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Control unit 12 Input circuit 14 Microcomputer 16 Output circuit 18 Communication system 20,24,28,32,36 ... 40,50,52,5
4 Line 22 Measuring device (accelerator pedal position) 26 Measuring device (throttle valve position) 30 Measuring device (air mass flow rate) 34 Measuring device (engine rotation speed) 42 ... 46 Measuring device (other operating variables) 48 Throttle valve 100 Driver Desired torque forming stage 102, 106, 126, 132, 148, 200, 2
07, 212, 302, 319 Coupling stage 104 Loss or consumption torque forming stage 108 Calculation program 110 Conversion stage 114, 122, 134, 146, 324 Switching element 116 Characteristic curve group 118, 130 Controller (PID) 120, 128, 142 , 210 Limiter 124 Memory cell or characteristic curve group 136 Comparison stage 138 Delay element 140 Negative slope detection stage 144 Minimum torque value formation stage 202 Integrator 204 Correction stage 206 Inversion stage 208 Minimum value selection stage 300, 304, 308, 314 322, 338 Comparison stage 306, 318, 330 AND connection 310 Gradient formation stage 312 Low-pass filter 316, 325 Delay stage 317, 328, 334, 336 OR combination 320 Absolute value formation stage 329, 332 Flip flop B_abglich Air quality Permissible condition for flow rate adjustment B_eauew Permissible condition for injection cutoff B_eauewd Permissible condition for continuous injection cutoff B_eauewv Temporary permissible condition for injection cutoff B_eauewb Operating state signal B_llr Idling operation state DMSEAUW Limit value dk Control amount TEd AUEL (Ignition angle) EA Injection E_dkg Error in throttle valve transmitter E_hfm Error in air mass flow sensor E_Vfzg Error in vehicle speed sensor fkminmin Minimum torque correction factor fkmsdk Air mass flow adjustment value Fra Mixture correction factor Gang Gear transmission ratio hfm Air mass flow rate mifa Desired target torque of driver mimin Calculated minimum torque value mimin Correction minimum torque value misoll Correction torque target value misoll_res Torque target value mover Loss or consumption torque mn Minimum torque value in normal operation msdk Corrected air mass flow rate value mshfm Measured air mass flow rate value nis Actual rotation speed nLLRsoll Engine target idling rotation speed nmot Engine rotation speed NUEWB Safe rotation speed (monitor rotation speed) ) RList Actual filling signal rLkorr Correction coefficient for minimum torque value rLsoll Filling target value S_kl15 Ignition injection ti Control amount (injection cutoff) TWDP waiting time TWDSM waiting time TWEUB Predetermined time VEAUWMNMN vehicle speed threshold Vfwdk speed Valve position wped Accelerator pedal position αz Ignition angle target value

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02P 5/15 F02P 5/15 M

Claims (22)

[Claims] 1. A method for controlling an internal combustion engine, wherein the torque of the internal combustion engine is set as a function desired by a driver, the rotational speed of the internal combustion engine being measured and limited to a predetermined value. In order to limit the rotation speed, a rotation speed limit controller that limits the engine rotation speed to a predetermined monitor rotation speed is used. The rotation speed limit controller first limits the engine rotation speed to the monitor rotation speed. The torque is reduced by engagement of the internal combustion engine with the air supply and / or ignition and / or fuel supply, and additionally, when at least one predetermined error condition is present, at least one cylinder of the internal combustion engine A method for controlling an internal combustion engine, wherein the fuel supply is completely shut off. 2. A target torque for the internal combustion engine is determined as a function of the driver's desire, the target torque being reduced by the rotational speed limiting controller when the rotational speed exceeds the predetermined monitor rotational speed. The method of claim 1, wherein the method is performed. 3. The method according to claim 1, wherein the monitor rotation speed is a function of an accelerator pedal position or a driver's desire. 4. An engine according to claim 1, wherein the air supply amount to the internal combustion engine is reduced to a minimum value, and the ignition angle is reduced to a predetermined delayed ignition angle. 4. The method as claimed in claim 1, further comprising reducing to a predetermined minimum possible value without misfiring. 5. The rotational speed limiting controller reduces the torque output of the internal combustion engine without combustion misfire by reducing the fuel supply to the internal combustion engine to a possible value without combustion misfire in stratified operation. 5. The method according to claim 1, wherein the value is reduced to a possible value. 6. The rotational speed limiting controller reduces the torque output of the internal combustion engine by reducing the air supply amount and the fuel supply amount to the internal combustion engine to a value that can be obtained in homogeneous operation without a combustion misfire. 2. The method as claimed in claim 1, wherein the value is reduced to a value possible without a combustion misfire.
Any one of the methods 5 to 5. 7. The fuel supply system according to claim 1, wherein the fuel supply is reduced or completely shut off via an injection valve and / or a tank vent valve in order to reduce the fuel supply. Either way. 8. The method according to claim 1, further comprising an idling rotation speed controller for providing a predetermined target idling rotation speed, wherein the monitor rotation speed is higher than the target idling rotation speed. 9. The control element for controlling the air supply can be completely closed in order to limit the engine speed to the monitor speed.
Either way. 10. A predetermined minimum torque that can be corrected by the monitor rotational speed limit controller without shutting off the fuel supply, resulting from a correction of the mixture and / or the air mass flow signal and air from a redundant sensor. 10. The method according to claim 1, wherein the correction is made by means of a characteristic value obtained from a comparison with a mass flow signal. 11. The method according to claim 1, wherein the correction of the charge signal indicative of the basis of the basic injection time takes place via a characteristic value of the mixture and / or via an air mass flow signal from a redundant sensor. Item 10. The method according to any one of Items 1 to 10. 12. The method according to claim 1, wherein the correction is formed from a minimum of the same direction correction values of the mixture adaptation and the air mass flow adaptation. 13. The method of claim 1, wherein said shut-off occurs when a minimum settable torque is not settable. 14. An air mass signal of a main load sensor and a second
2. The method according to claim 1, wherein the interruption is performed when a comparison with the air mass signal of the load sensor exceeds an allowable limit. 15. The method of claim 1, wherein said shutting down occurs when an error in a primary load sensor is detected. 16. The method according to claim 1, wherein the shut-off is performed when the driving speed falls below a predetermined threshold. 17. The method according to claim 1, wherein once the conditions for effecting the interruption of the fuel supply have been established, the interruption is maintained for the entire remaining driving cycle. . 18. The control system according to claim 1, wherein the rotational speed limiting controller is selectively or additionally provided in a second redundant software channel of a microcomputer of the control unit for controlling the internal combustion engine or in a second monitor computer. The method according to any one of claims 1 to 17, wherein the method is provided. 19. The method according to claim 1, wherein the monitor rotation speed limitation processes a rotation speed signal derived from a redundant rotation speed sensor, for example, a camshaft phase sensor, as the rotation speed signal. Either way. 20. The method according to claim 1, wherein the monitor limit controller is activated only when the accelerator pedal is released. 21. The method according to claim 1, wherein the rotational speed limiting controller reduces the throttle valve angle and the ignition angle directly and / or reduces the fuel supply. 22. An electronic control unit for controlling the torque of the internal combustion engine as a function of the driver's desire, for measuring the rotational speed of the internal combustion engine and for limiting the rotational speed of the internal combustion engine to a predetermined rotational speed. A control device for an internal combustion engine having an electronic control unit including a limit controller, wherein when a predetermined monitor rotational speed is exceeded, firstly, air supply engagement and ignition engagement and / or engagement with fuel supply are engaged. Reducing the torque and, in the presence of at least one predetermined error condition, additionally, completely shutting off the fuel supply to at least one cylinder, thereby reducing the engine speed to the predetermined monitor speed. A control device for an internal combustion engine, comprising: a monitor rotation speed limit controller for limiting the rotation speed to a limit.