SE537190C2 - Method and system for controlling an internal combustion engine through control of combustion in an internal combustion chamber during the current combustion cycle - Google Patents

Abstract

The present invention relates to a method of controlling an internal combustion engine (101), said combustion engine (101) comprising at least one combustion chamber (201) and means (202) for supplying fuel to said combustion chamber (201), wherein combustion in the said combustion chamber (201) takes place in combustion cycles. The method comprises: during a first part of a first combustion cycle, with the aid of a first sensor means determining a first parameter value representing a quantity during combustion in said combustion chamber (201), and based on said first parameter value, regulating combustion during a subsequent part of said first combustion combustion cycle, wherein in said control the combustion during said subsequent part of said first combustion cycle is regulated with respect to a work carried out during combustion. The invention also relates to a system and a vehicle.

Description

FIELD OF THE INVENTION Field of the Invention systems and a vehicle, as well as a computer program and a computer program product, which implement the method according to the invention.

Background of the Invention The following description of the invention constitutes a background description of the invention, and thus does not necessarily constitute a prior art.

When it comes to vehicles in general, a variety of driveline configurations occur. For example. the gearbox can be a manually geared gearbox or an automatic gearbox. In the case of heavy vehicles, it is often undesirable for them to be able to be driven in a way that is as comfortable as possible for the driver, which usually means that the gearboxes' gear changes should be carried out automatically with the help of the vehicle's control system. It has therefore also become all the more common with automatically shifting gearboxes in heavy vehicles.

When it comes to automatic gearboxes of the type that often occur in passenger cars, the efficiency is often too low for the use of this type of gearbox to be justified other than for use in e.g. city buses and distribution vehicles in cities, where frequent starts and stops are common. Also with regard to these types of vehicles, however, it is becoming increasingly common for drivelines of the type below to be used. 1 537 190 Automatic shifting in heavy vehicles often consists of a control system-controlled shifting of "manual" shift gears, ie. VdxellAdor consists of one pair of gears per vdxel, where the gear ratios are distributed in standard steps, e.g. due to the fact that these are significantly cheaper to produce, but also due to higher efficiency compared to conventional automatic transmission doors. In such vdxellAdor, a clutch, which can be formed by a clutch automatically controlled by the vehicle's control system, is used to connect the vehicle's engine to the vdxelladan. This clutch / vdxellada can dven e.g. be of double coupling type.

In principle, the coupling in such vehicles only needs to be used when starting the vehicle from a standstill, as other shifts can be performed by the vehicle's control system without the coupling being opened. However, in cases where the clutch consists of a clutch automatically controlled by the vehicle's control system, the clutch is often used to open / close the driveline even when shifting. Regardless of how the shift is performed, it is undesirable that the shift is performed in a way that is both perceived as comfortable by the driver of the vehicle while the shift is also performed in a way that is gentle on the components of the driveline.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method of controlling an internal combustion engine. This object is achieved by a method according to claim 1.

The present invention relates to a method of controlling an internal combustion engine, said internal combustion engine comprising at least one combustion chamber and means for supplying fuel to said combustion chamber, wherein combustion in said internal combustion chamber occurs. During a first part of a first combustion cycle, with the aid of a first sensor means a first parameter value is established representing a quantity in combustion in said combustion chamber, and - based on said first parameter value, combustion is regulated during a subsequent part of said first combustion cycle, wherein in the said regulation the combustion during the said subsequent part of the said first combustion cycle is regulated with respect to a work carried out during the combustion. The regulation with regard to work carried out during the combustion can e.g. is performed by regulating the combustion against a first average pressure during the combustion cycle, such as an average pressure corresponding to a desired torque.

As mentioned above, in the case of heavy vehicles, gears of the type commonly used in manually shifted vehicles are often used, whereby shifting is performed automatically by the vehicle control system. When shifting from one gear ratio to another, the driveline is broken so that after loading the new gear Ater is closed.

Before the Ater driveline is switched on, however, the speed of the internal combustion engine must be synchronized with the expected speed of the gearbox. Adan's input shaft with the new gearbox engaged so that unwanted jerks / oscillations do not occur when shifting. This change, synchronization, of the internal combustion engine speed can be performed in different ways, which is also described in the prior art.

In addition to this synchronization of the internal combustion engine speed with the rest of the driveline speed before closing the driveline, at least when shifting with the clutch engaged, the torque of the internal combustion engine on the output shaft is controlled so that the gearbox becomes "torqueless", ie. the torque delivered by the internal combustion engine is controlled to an appropriate level for reducing and preferably eliminating the torque transmitted between the internal combustion engine and the drive wheel engagement point, whereby disengagement or loading of gear can be carried out without undesired jerks due to the driveline being broken / barred ongoing power transmission. In such a changeover, it is thus unquestionable that the torque emitted by the internal combustion engine can be controlled very precisely in order to eliminate such driving force transmission as far as possible.

According to the present invention there is provided a method in which a first parameter value relates to a quantity in the combustion, such as e.g. a representation of a pressure radiating in the combustion chamber, is determined at at least one time after the combustion during a combustion cycle has been started but before the combustion cycle has ended, and based on said first parameter value the combustion is regulated during a subsequent part of said first combustion cycle. which is carried out during the said combustion cycle. As explained below, the parameter value can be determined several times during an ongoing combustion cycle, in order to thereby establish new control parameters for e.g. the combustion on a number of occasions during the ongoing combustion cycle.

According to the invention, the combustion is thus regulated during an ongoing combustion cycle, the combustion being regulated based on at least one parameter value representing a quantity during the combustion, this quantity being directly affected by the hitherto challenging part of the combustion. Thus, at e.g. a situation where a certain torque emitted by the internal combustion engine is undesirable, such as a torque emitted on the output shaft of the internal combustion engine, a work actually obtained so far during the combustion cycle is evaluated and compared with a hitherto related received 4,537 190 work. Furthermore, a condition actually radiating during combustion can be compared with a expected ratio corresponding to combustion in order to determine whether the combustion continues as expected. Combustion parameters can then be regulated as needed to control the combustion in order to direct the combustion towards a desired work generated during the combustion cycle.

The work generated during the combustion cycle can e.g. is expressed as a desired torque as a desired average torque during the combustion cycle.

The torque emitted by the internal combustion engine has a direct connection with the pressure in the combustion chamber, whereby the torque can also be represented by the pressure in the combustion chamber. This also means that the desired delivered average torque during a combustion cycle can be obtained by regulating the combustion against a corresponding average pressure, whereby the combustion process can thus be controlled against a desired average pressure during the combustion cycle. Thus, said quantity can be constituted by the pressure radiating in the combustion chamber, a representation of this pressure, which e.g. can be obtained directly by means of a pressure sensor arranged in the combustion chamber, or via another type of sensor for feeding another quantity with the aid of which a representation of a corresponding pressure can be obtained.

Thus, e.g. one up to e.g. the time at which said first parameter was determined average pressure is compared with a expected average pressure up to this time, whereby subsequent combustion can be regulated based on said comparison. The combustion can also be arranged to be regulated e.g. at a difference between a fixed value and a expected value at said time. The present invention thus provides a method which means that the work carried out during combustion can be controlled very precisely, and thus also the torque delivered on the output shaft of the internal combustion engine can be controlled very precisely. At e.g. a request for a certain work performed by the internal combustion engine on the output shaft (torque delivered), this can be converted into a combustion chamber work, where consideration is given to internal losses, etc., which is also explained in the detailed description below.

The method according to the invention can e.g. used in e.g. situations where undesired jerks / oscillations despite alit have occurred in the driveline, where a very rapid regulation of the combustion can be performed in order to counteract oscillations by regulating the torque delivered on the output shaft of the internal combustion engine based on radiating oscillations in the driveline, where drilling can be obtained. based on e.g. signals from speed sensors.

The control of the combustion can be arranged to be carried out individually for a conventional cylinder, and it is also possible to regulate a combustion during a subsequent combustion cycle based on information from one or more previous combustion processes.

The process of the present invention can e.g. is implemented using one or more FPGAs (Field-Programmable Gate Array) circuits, and / or one or more ASIC (application-specific integrated circuit) circuits, or other types of circuits that can handle the desired Peraking Speed.

Additional features of the present invention and advantages thereof will be apparent from the following detailed description of exemplary embodiments and the accompanying drawings.

Brief Description of the Drawings Fig. 1A schematically shows a vehicle in which the present invention can be used.

Fig. 1B shows a control unit in the control system for the vehicle shown in Fig. 1A.

Fig. 2 shows the internal combustion engine of the vehicle shown in Fig. 1A in more detail.

Fig. 3 shows an exemplary method according to the present invention.

Fig. 4 shows an example of an estimated pressure pair for a combustion, as well as an actual pressure pair up to a first crank angle position.

Figs. 5A-B show an example of control in situations with more than three injections.

Fig. 6 shows an example of an MPC control.

Detailed Description of Embodiments Fig. 1A schematically shows a driveline in a vehicle 100 according to an embodiment of the present invention. The driveline comprises an internal combustion engine 101, which in a conventional manner, via a shaft extending on the internal combustion engine 101, usually via a flywheel 102, is connected to a gearbox 103 via a clutch 106.

The internal combustion engine 101 is controlled by the vehicle's control system via a control unit 115. Likewise, the clutch 106, which e.g. can be constituted by an automatically controlled clutch, and the gearbox 103 of the vehicle's control system by means of one or more applicable control units (not shown). Of course, the vehicle's driveline can also be of another type such as e.g. of a type with 7 537 190 conventional automatic gearbox or of a type with a manually geared manual gearbox etc.

A shaft 107 emanating from the gearbox 103 drives drive wheels 113, 114 in the usual manner via end gear and drive shafts 104, 105. Fig. 1A shows only one axle with drive wheels 113, 114, but in the usual way the vehicle may comprise more than one axle provided with drive wheels, as well as one or more additional axles, such as one or more stand axles. The vehicle 100 further comprises an exhaust system with a post-treatment system 200 for the usual treatment (purification) of exhaust emissions resulting from combustion in the combustion chamber of the internal combustion engine 101 (eg cylinders).

Furthermore, internal combustion engines in vehicles of the type shown in Fig. 1A are often provided with controllable injectors for supplying the desired amount of fuel at the desired time in the combustion cycle, as at a specific piston position (crank angle degree) in the case of a piston engine, to the combustion engine combustion chamber.

Fig. 2 schematically shows an example of a fuel injection system for the internal combustion engine 101 exemplified in Fig. 1A. The fuel injection system consists of a so-called Common Rail systems, but the invention is equally applicable to other types of injection systems. Fig. 2 shows only a cylinder / combustion chamber 201 with a piston 203 acting in the cylinder, but the internal combustion engine 101 in the present example consists of a six-cylinder internal combustion engine, and can generally consist of an engine with any number of cylinders / combustion chamber, such as e.g. . any number of cylinders / combustion chambers in the range 1-20 or more. The internal combustion engine further comprises at least one respective injector 202 for conventional combustion chamber (cylinder) 201. Each respective injector is thus used for injecting (supplying) fuel into a respective combustion chamber 201. Alternatively, two or more injectors per combustion chamber may be used. The injectors 202 are individually controlled by respective actuators (not shown) arranged at the respective injector, which are based on received control signals, such as e.g. from the control unit 115, controls the opening / closing of the injectors 202.

The control signals for controlling the opening / closing of the injectors 202 by the actuators can be generated by any applicable control unit, as in this example by the motor control unit 115.

The engine control unit 115 thus determines the amount of fuel that is actually to be injected at the given time, e.g. based on the prevailing operating conditions of the vehicle 100.

The injection system shown in Fig. 2 thus consists of a so-called Common Rail system, which means that all injectors (and thus combustion chambers) are filled with fuel from a common fuel clay 204 (Common Rail), which by means of a fuel pump 205 is filled with fuel from a fuel tank (not shown) at the same time as the fuel 204, also by means of the fuel pump 205, is pressurized to a certain pressure. The highly pressurized fuel in the common tube 204 is then injected into the combustion chamber 201 of the internal combustion engine 101 at the opening of the respective injector 202. Several openings / rods of a specific injector can be made during one and the same combustion cycle. Furthermore, each combustion chamber is provided with a respective pressure sensor 206 for emitting signals of a pressure radiating in the combustion chamber to e.g. the control unit 115. The pressure sensor can e.g. be piezo-based, and should be so fast that it can emit crank angle resolving 9 537 190 pressure signals, such as e.g. at the usual crank angle or more often With the aid of systems of the type shown in Fig. 2, the combustion during a combustion cycle in a combustion chamber can be controlled to a large extent, e.g. by utilizing multiple injections, where injection times and / or duration can be regulated, and where data from e.g. the pressure sensors 206 can be taken into account in the control. According to the invention, e.g. injection times and / or duration of the respective injection and / or injected industry during the incineration based on data from the incineration in order to regulate the incineration with respect to work performed during the incineration cycle, which e.g. can be performed by regulating the pressure changes that occur in the combustion chamber during combustion, whereby the regulation e.g. can be controlled against a desired average pressure during a combustion cycle, with the result that a very precise control of the emitted torque of the internal combustion engine can be obtained at e.g. vaxling.

Fig. 3 shows an exemplary method 300 according to the present invention, in which the method according to the present example is arranged to be carried out by the motor control unit 115 shown in Figs. 1A-B.

Generally, control systems in modern vehicles consist of a communication bus system consisting of one or more communication buses for interconnecting a number of electronic control units (ECUs) such as the control unit, or controller, 115, and various components arranged on the vehicle.

As an edge, such control systems may comprise a large number of 537,190 control units, and the responsibility for a specific function may be divided into more than one control unit.

For the sake of simplicity, in Figs. 1A-B, only the motor control unit 115 in which the present invention is implemented in the embodiment shown is shown. However, the invention can also be implemented in a control unit dedicated to the present invention, or in whole or in part in one or more other control units already existing in the vehicle. In view of the speed at which calculations according to the present invention are carried out, the invention can be arranged to be implemented in a control unit which is specially adapted for real-time calculations of the type as below. Implementation of the present invention has shown that e.g. ASIC and FPGA solutions are lighted for and selection can handle calculations according to the present invention.

The function of the control unit 115 (or the control unit (s) to which the present invention is implemented) according to the present invention may, in addition to being dependent on sensor signals from the pressure sensor 202, e.g. depend on signals from other controllers or sensors. In general, control units of the type shown are normally arranged to receive sensor signals from different parts of the vehicle, as well as from different control units arranged on the vehicle.

The control is often controlled by programmed instructions. These programmed instructions typically consist of a computer program, which when executed in a computer or controller causes the computer / controller to perform the desired control, such as the process steps of the present invention.

The computer program usually forms part of a computer program product, where the computer program product comprises an applicable storage medium 121 (see Fig. 1B) with the computer program stored on said storage medium 121. The digital storage medium 121 may e.g. consists of any of the group: ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), Flash memory, EEPROM (Electrically Erasable PROM), a Hard Disk Drive, etc., and be arranged in or in connection with the control unit, the computer program being executed by the control unit. By following the instructions of the other computer program, the behavior of the vehicle in a specific situation can thus be adapted.

An exemplary control unit (control unit 115) is shown schematically in Fig. 1B, wherein the control unit may in turn comprise a calculating unit 120, which may be constituted by e.g. flagon appropriate type of processor or microcomputer, e.g. a Digital Signal Processor (DSP), one or more Field-Programmable Gate Array (FPGAs) circuits or one or more circuits with an Application Specific Integrated Circuit (ASIC) function. The calculating unit 120 is connected to a memory unit 121, which provides the calculating unit 120 e.g. the stored program code and / or the stored data calculation unit 1 need to be able to perform calculations. The calculation unit 120 is also arranged to store partial or final results of calculations in the memory unit 121.

Furthermore, the control unit is provided with devices 122, 123, 124, 125 for receiving and transmitting input and output signals, respectively. These input and output signals may contain waveforms, pulses, or other attributes, which of the input signals receiving devices 122, 125 may be detected as information for processing the calculation unit 120. The output signals 123, 124 for transmitting output signals are arranged to convert calculation results from the calculation unit. 120 to output signals for transmission to other parts of the vehicle control system and / or the component (s) for which the signals are intended. Each of the connections to the devices for receiving and transmitting input and output signals, respectively, may be one or more of a cable; a data bus, such as a CAN bus (Controller Area Network bus), a MOST bus (Media Oriented Systems Transport), or flagon other bus configuration; or by a wireless connection.

Returning to the process 300 shown in Fig. 3, the process starts in step 301, where it is determined whether control of the combustion process should be performed. The regulation according to the invention can e.g. be arranged to be carried out continuously as soon as the internal combustion engine 101 is started. Alternatively, the regulation can be arranged to be performed only in certain situations, such as e.g. when opening / closing the driveline at / during shifting, or to counteract the occurrence or already occurring oscillations in the driveline, or in other applicable situations where it is desirable to have a very precise regulation of the torque delivered by the internal combustion engine.

The method according to the present invention thus consists of a method for controlling the combustion engine 101 while combustion takes place in said combustion chamber 201 in combustion cycles. As the edge, the term combustion cycle is defined as the steps a combustion at an internal combustion engine includes, such as e.g. the two-stroke engine of the two-stroke engine and the four-stroke engine of the four-stroke engine. The term also includes cycles where no fuel is actually injected, but where the spirit of the internal combustion engine is driven at a certain speed, such as by the vehicle's drive wheel via the driveline at e.g. sldpning. Ie. even if no injection of fuel is carried out, a combustion cycle still takes place for e.g. every two vary (for four-stroke engine), or e.g. each vary (two-stroke engine), which the combustion engine's output shaft 13 537 190 rotates. The same applies to other types of internal combustion engines.

In step 302 it is determined whether a combustion cycle has or will be started, and when so, the procedure proceeds to step 303 at the same time as a parameter in the representative injection number is set equal to one.

In step 303, one of the work requested by the combustion engine during the combustion cycle is determined. For example. the requested work can consist of a drill guard for the moment to facilitate e.g. waxing, where the drilling value has been advanced / determined by e.g. the function that controls wobbling. The corresponding pressure drill value can advantageously be tabulated in the memory of the control system in order to be able to be quickly retrieved when regulating according to the present invention.

In general, it applies that the supply of the quantity of industry both in terms of quantity and in what way, ie. the one or more fuel injections to be performed during the combustion cycle are normally predefined, e.g. depending on the work (torque) that the internal combustion engine is to perform during the combustion cycle, since modification of the established injection schedule is not performed during an ongoing combustion cycle according to prior art. Predefined injection schedules can e.g. are tabulated in the vehicle's control system for a large number of operating cases, such as different engine speeds, different work required, different combustion air pressures, etc., where tabulated data e.g. may have been produced by appropriate tests / feeds at e.g. development of an internal combustion engine and / or vehicle, whereby the applicable injection schedule can be selected based on prevailing conditions, and where the injection schedule can be selected e.g. based on a request for a certain torque delivered, such as 14 537 190 e.g. from a function that controls e.g. vaxling. These injection schedules can consist of the number and properties of the injections in the form of e.g. time (crank angle layer) for start of injection, length of injection, injection pressure, etc., and all6 are stored for a large number of operating cases in the vehicle's control system.

Based on the required work determined in step 303, an injection schedule is then established in step 304 which is expected to result in an undesired work, such as average torque, during the combustion cycle combustion, where the injection schedule is selected based on prevailing conditions, e.g. speed, combustion air pressure.

The torque delivered during the combustion engine's torque generally constitutes an average of the work the internal combustion engine develops, and this work is usually called MEP (mean effective pressure), ie. pressure average.

In general, the following relationship applies between torque M and power P: M = 2n-N (1), where N is the internal combustion engine speed, which is available in the vehicle's control system.

Furthermore, the following relationship between pressure mean value AMP and power applies: MEP = Pn, vdiv (2) 537 190, where nc is the number of variables per combustion cycle, ie. 2 for four-stroke engine and 1 for two-stroke engine. Vci is the volume of the combustion chamber.

By utilizing eq. (1) In order to describe the power P in equation (2), the relationship between torque M and the mean pressure, for a four-stroke engine, can thus be written as: 4n-M MEP = (3) CEO Thus, a pressure mean corresponding to a desired torque in the internal combustion chamber's combustion chamber determined by using eq. 3. Since 11d is a bachelor's degree, MEP can e.g. tabulated against torque in the vehicle's control system to allow quick access to a drilling rig against which the pressure in the combustion chamber is to be regulated.

The work of an internal combustion engine, such as e.g. expressed in medium pressure, however, can be defined in different ways. For example. work will be performed during the combustion, but where all this work due to e.g. losses will not be available on the output shaft of the internal combustion engine.

The work performed in the combustion chamber is generally called IMEP (indicated mean effective pressure), which is assumed to represent the resulting work during the combustion in the combustion chamber.

Thus, since an internal combustion engine generally includes losses, such as pump losses during gas exchange work and friction loss losses, the IMEP does not directly represent the torque delivered on the output shaft of the internal combustion engine. At e.g. a torque request from another function occurring at the vehicle, such as e.g. a function for controlling 16 537 190 shifting as above, however, a work done on the output shaft of the internal combustion engine is normally requested, which due to the losses of the internal combustion engine thus means that the required mean pressure to obtain desired output on the output shaft does not correspond exactly to eq. (3).

The work performed on the output shaft of the internal combustion engine is generally called BMEP (Brake mean effective pressure), which consists of MEP, but compensated for the losses of the internal combustion engine.

These losses can be projected specifically, but usually the efficiency of the internal combustion engine is chosen, whereby BMEP can be determined as: BMEP = timed / MEP ?, (4) Dr Pmech is the efficiency of the internal combustion engine. u r-mech can be tabulated for a large number of operating conditions, and with very good accuracy, whereby a rapid conversion between BMEP and IMEP can be performed if necessary.

Thus, the pressure average value IMEP required in the internal combustion engine combustion chamber in order to obtain the desired output torque of the internal combustion engine torque can be written as: 1 47rM IMEP = Pmech Vd (5) At a request for a torque on the corresponding combustion engine the combustion is easily and quickly determined, and thus the present invention relates to a method for controlling the combustion in such a way that the combustion is controlled against this pressure medium MEP by utilizing the control of the combustion for a combustion cycle, during the ongoing combustion cycle. The control according to the invention can be arranged to be carried out continuously for successive combustion cycles in order to ensure a very precise delivery of the requested torque during e.g. a swapping procedure.

The pressure mean value IMEP in the combustion chamber during a combustion cycle can also be written as: 180CAD 1 IMEP = - f pdV (6) Vd -180CAD, where CAD stands for camshaft degrees, ie. integration is performed over an entire combustion cycle.

In step 304, then, according to the above, an injection scheme is determined which is expected to result in a desired pressure average IMEP and thus undesired torque delivered during the combustion cycle combustion, and according to this embodiment a predetermined injection scheme is thus applied to the combustion cycle. started during the combustion cycle, such as only after at least one injection has been performed during the combustion cycle, or after at least one injection has been started.

Thus, fuel injection is normally performed according to a predetermined schedule, where a plurality of injections may be arranged to be performed during one and the same combustion cycle.

This means that the injections can be relatively short. For example. There are injection systems with 5-10 fuel injections / combustion, but the number of 18,537 190 fuel injections can also be significantly larger than sA, such as e.g. on the order of 100 fuel injections during a combustion cycle. The number of possible injections is generally controlled by the speed of the organs with which the injection is performed, ie. in the case of Common Rail systems of how quickly the injectors can be opened shut down.

According to the present example, at least two fuel injections are carried out during one and the same combustion cycle, but as has been named and as shown below, several injections can be arranged to be performed, as well as only one.

The injection schedule is thus in the present example determined in advance in order to obtain some certain work (pressure average value). A first injection is injected, and in step 305 it is determined whether said first injection has been performed, and in that case the procedure proceeds to step 306, where it is determined whether all the injections have been performed. Since this is not the case in the present example, the procedure proceeds to step 307 at the same time as it is straightened up with a next injection.

Furthermore, by using the pressure sensor 206, it is determined continuously, as at applicable intervals, e.g. every 0.1-10 crank angle degrees, radiating pressure in the combustion chamber.

The process of combustion can generally be described with the pressure change in the combustion chamber which the combustion gives rise to. The pressure change during a combustion cycle can be represented by a pressure pair, ie. a representation of how the pressure in the combustion chamber varies during combustion. As the combustion progresses as expected, the pressure in the combustion chamber will be equal to the initially estimated, but as soon as the pressure deviates from the estimated pressure, the work that has been carried out will also deviate from that previously assumed.

If the combustion after the first injection has thus been carried out exactly as expected, the conditions in the combustion chamber will correspond to the conditions intended with the injection, as well as the resulting average pressure will correspond to the expected average pressure up to this point. As soon as the conditions deviate from the intended conditions, however, the resulting average pressure will deviate from the expected average pressure, likewise the subsequent part of the combustion will be affected because the conditions in the combustion chamber, e.g. with respect to pressure / temperature, at the next injection will not correspond to expected conditions.

In practice, the actual pressure gauge will also in all probability deviate from the predicted pressure gauge during the combustion process due to e.g. deviations from the modeled combustion, etc. This is asked in Fig. 4, where a predicted pressure gauge 401 for an example injection scheme is shown (very schematic), i.e. the expected pressure gap for the combustion chamber when injection is performed according to the selected injection profile. This prediction of the pressure gap can e.g. performed as described below.

Fig. 4 also shows an actual pressure groove 402 up to the crank angle position Ti, which constitutes the driving position after the said first combustion has been carried out. Preferably, the pressure in the combustion chamber is thus determined substantially continuously, such as e.g. at habit crank angle degree, habit tenth crank angle degree or with other lamp interval 537 190 during the entire combustion. As can be seen in Fig. 4, the actual pressure pair deviates up to 91 from the estimated pressure pair 401. This in turn means that the hitherto average pressure up to the crank angle position has also deviated from the expected average pressure.

Since the pressure in the combustion chamber after the first injection has been carried out differs from the corresponding estimated pressure at the crank angle position 91, the conditions in the combustion chamber at the time of the next injection insp2 will differ from predicted conditions, so that subsequent burns also follow the previously established injection schedule would still be used. The average pressure so far also differs from the one predicted, and thus it is not at all certain that the desired average pressure will be achieved, and thus related work will be performed, during the combustion cycle. Thus, it is also not all certain that it is the originally established injection schedule that constitutes the most preferred injection schedule in the effort to achieve the desired average pressure during the combustion cycle, since the pressure average depends on the pressure gauge, which in turn depends on how fuel is supplied to the combustion.

In step 308, therefore, an injection schedule is again established in order to direct the combustion to a desired average pressure during the combustion, and in the determination, an average pressure resulting hitherto during the combustion can be determined, whereby an injection schedule can be determined which results in a desired pressure. The process steps can then be repeated after each injection to continuously control the combustion against the desired pressure average. 21 537 190 The regulation can e.g. carried out according to the calculations shown below, alternatively according to other applicable calculations with a corresponding purpose, and thus repeated as below during the ongoing combustion cycle to change the injection schedule during ongoing combustion if the conditions actually radiating in the combustion chamber deviate from predicted proportions. to a greater extent achieve Unwanted exhausted work. The pressure in the combustion chamber can be determined continuously during combustion by using the pressure sensor 206 to determine a mean pressure obtained so far.

When estimating the average color pressure during the remaining combustion, however, an estimation of the pressure change during the combustion is also required. This can be estimated as follows.

The combustion can, as is the edge for those skilled in the art, be modeled according to eq. (7): dQ = Kcalibrate (QfuelQ) (7), where Kcal ibrate is used to calibrate the model. Kcal ibrate consists of a constant which is usually of the order of 01, but may also be arranged to assume second values, and which is determined individually cylinder by cylinder or for a certain engine or motor type, and depends in particular on the design of the injectors nozzles (diffusers) .

Qftd constitutes the energy value for injected industry quantity, Q constitutes combustion energy quantity. The combustion dQ is thus proportional to the injected amount of fuel minus the amount of fuel consumed so far. The combustion dQ can alternatively 22 537 190 be modeled by utilizing another applicable model, where e.g. Other parameters can also be taken into account. For example. the combustion can also constitute a function that depends on a model of the turbulence that arises during the supply of air / fuel, which can affect the combustion to varying degrees depending on the amount of air / fuel supplied.

Regarding the industry injections, these can e.g. is modeled as a sum of step functions: U = (j) (tinj. start) k) (pct - (tinj. end) k) (8) k = 0 Bransleflodet matt i tillford mass m at an injection k, ie. how the fuel enters the combustion chamber during the time window u when the injection is performed, expressed in the time that elapses below the tissue angle degree T-interval that the injector is open, for a specific injection k can be modeled as: dm = f (m) u (9) days m constitutes injected industry volume, and f (m) e.g. depends on injection pressure etc. f (m) can e.g. be measured or estimated in advance.

The energy value 0 -t.LHV for the industry, such as diesel or petrol, is generally stated, whereby such a general statement can be used. The energy value can also be specified by e.g. the manufacturer of the industry, or be approximated for e.g. a country or region. The energy value can also be arranged to be estimated by the vehicle's control system. With the energy value, eq. (7) is released and the heat release as the combustion proceeds is determined. 23 537 190 Furthermore, by using a predictive heat release equation, the pressure change in the combustion chamber can e.g. is estimated as: dp = c7pd (2 yY-1 p Ed (p) (10) The pressure change is thus expressed in crank angle degrees 9, which meant an elimination of the combustion engine speed dependence in the calculations. y generally constitutes the heat capacity ratio, ie 7_ P = P dar C and / or C are generally developed and Cp-R tabulated for different molecules, and by combining the combustion chemistry, these tabulated values can be used together with the combustion chemistry to thereby calculate the effect of each molecule (eg water, nitrogen, oxygen, etc.) on t. eg the total Cp value, whereby this can be determined for the calculations above with good accuracy, in advance or during, for example, ongoing combustion, Alternatively, Cp and or C, can be approximated in an appropriate manner.

Integration of eq. (10) with the following results: dQ y dVvy— 1) d9 P = PinitialdP = Pinitial f (thp y - 1 Pchi)) v Pthitiate constitutes an initial pressure, which before the start of the combustion step of the combustion e.g. may be the ambient pressure of non-turbocharged internal combustion engines, or a radiating combustion air pressure of turbocharged engine. When estimation is performed at a later time during the combustion cycle, such as estimation in step 307 after an injection has been made, the initial 24 537 190 and with the aid of the pressure sensor 206 can be determined, ie. p (pi in the present example. V ((p), ie the volume of the combustion chamber as a function of crank angle, can advantageously be tabulated in the memory of the control system or alternatively calculated in a suitable manner, dV whereby also dço can be determined.

Thus, the pressure p in the combustion chamber can be estimated for the entire combustion, ie. the expected curve 401 in Fig. 4 can be estimated. Thus, even a expected average pressure for the subsequent part of the combustion cycle can be estimated by using eq. (6) above, and also for the entire combustion cycle where the actual pressure average can be applied to the part of the combustion cycle which has already elapsed.

The expected mean pressure value for a given injection scheme can thus be estimated using the above equations. In step 307, a plurality of different injection schedules can thus be evaluated according to the above equations, where the respective injection schedule will give rise to a specific pressure pair, and then the pressure mean value, which is estimated for the specific injection schedule.

Then an injection schedule for subsequent injections can be selected as e.g. expected to result in a pressure mean value that most closely corresponds to the desired pressure mean.

Control of the pressure in the combustion chamber can thus be performed by regulating the fuel injection, and by performing estimation of the pressure mean value for a number of different injection schedules with varying injection times / injection lengths / number of injections, an injection schedule can thus be established as far as possible or as high as possible. pressure average. Thus, in step 307, an injection schedule can be established, such as an injection schedule among a plurality of defined injection schedules, which best meet the desired pressure average, where this injection schedule can be determined individually cylinder by cylinder based on sensor signals from at least one pressure sensor in each sensor.

Regarding the mentioned injection schedules, it can e.g. there are a plurality of predefined injection schedules, whereby calculations of the above type can be performed for each of these available injection schedules. Alternatively, the calculations can be performed for the injection schedules that for some reason are most likely to result in the desired pressure average. For example. Injection schedules can be evaluated or rejected with respect to the total amount of industry that will be injected according to the schedule, where e.g. a large amount of industry e.g. can be assumed to result in a too high pressure average, especially if the resulting pressure average is above expected pressure average, and conversely, a combined total industry volume can at least in some cases be expected to result in a proposed pressure average.

So far, entire injection schedules for residual combustion have been evaluated, but the control can also be arranged to be performed for only the next injection after a previous injection, whereby senate injections can be handled afterwards. The injection scheme selected in step 307 can thus consist of only the next injection.

If an injection scheme has been selected in step 307, the procedure returns to step 304 for performing the next injection, which also gives rise to a combustion, and thus a pressure pair, where this is also likely to deviate from the previously predicted pressure pair. This also means that the combustion, even in subsequent injections, is likely to be affected by the prevailing conditions in the combustion chamber when the injection is started, as well as that the resulting pressure average value Anyo has changed from the expected.

Thus, in step 307, after a subsequent injection has been performed, a new injection strategy for the remaining injections, alternatively the subsequent injection, can be calculated by means of the above equations, the procedure then AtergAr to step 304 for performing a subsequent injection according to the new industry. injection strategy developed in step 307. The control can thus be arranged to be carried out according to the usual injection and when all the injections have been carried out, the procedure from step 307 to step 301 has been carried out for regulating a subsequent combustion cycle.

In the above calculations, after each injection, the current pressure determination is used by using the pressure sensor 206 as the initial as above to predict any pressure saving / pressure average values to establish a new injection schedule according to the now prevailing conditions in the combustion chamber, a bit into the combustion. Ie. p (after the first combustion and in a corresponding manner determined po_ for subsequent injections, whereby thus changed in calculations during the combustion cycle, and whereby the fuel injection is adapted to the prevailing conditions according to habitual injection, with the result that the injection schedule can be changed according to habitual injection.

The present invention thus provides a method which adapts the combustion as the combustion proceeds, wherein the combustion of the internal combustion engine can be very precisely controlled against a desired output torque, whereby procedures such as waxing can be performed with great accuracy and control during paging. In addition, the control can be used to counteract oscillations that may occur in the powertrain, where the internal combustion engine can be controlled very precisely in order to counteract unwanted effects such as oscillations through applicable torque control.

Thus, according to the present invention, the combustion during ongoing combustion is adapted based on deviations from the predicted combustion, and according to one embodiment each time an injection has been performed as long as further injections are to be performed.

Instead of evaluating a number of defined injection schedules in step 307, e.g. a regulator is used, which based on e.g. a fixed deviation between the desired pressure average and the hitherto obtained pressure average, with size and character, regulates subsequent combustion, where e.g. one or more subsequent injections can be adapted to how the combustion should have taken place and how it actually took place. For example. For example, the industry volume for subsequent injection according to the predetermined injection schedule can be increased if the pressure average is lower than expected, or reduced if the pressure average is higher than expected. This can be done for each subsequent injection, whereby a good control can be achieved.

The amount of fuel can e.g. is regulated by increasing / decreasing the industry volume by one industry volume obtained by multiplying the previously determined industry volume for 28 537 190 injection with the distinction between hitherto expected pressure average and hitherto actually obtained pressure average with some applicable constant.

According to the method described above, the injection schedule at the beginning of the combustion cycle has been determined based on tabulated values, but according to one embodiment the injection strategy can already be determined before the industry injection Oberjas in the manner described above, thus also the first injection is performed according to the above injection.

Furthermore, the control has hitherto been described in a set cidr the properties of a subsequent injection are determined based on prevailing conditions in the combustion chamber after the previous injection. However, the control can also be arranged to be performed continuously, whereby pressure determinations can be performed with the aid of the pressure sensor also during pagan injection, and whereby the injection schedule can be calculated and corrected by others until the next injection is started. Alternatively, even the ongoing injection can be affected by protruding changes in the injection schedule even in cases where a number of shorter injections are performed. The injection can also consist of a single longer injection, whereby changes of ongoing injection can be performed continuously, e.g. by so-called rate shaping, e.g. by changing the opening area of the injection nozzle and / or the pressure at which the fuel is injected based on estimates and the measured pressure value during the injection. Furthermore, fuel supply during combustion can include two fuel injections, where e.g. only the second or 'pada injections are regulated e.g. with the help of rate shaping. Rate shaping can also be applied in the case where three or more injections are performed. 29 537 190 Regarding the injection strategies to be evaluated, these can be developed in different ways. For example. different distributions between injections can be evaluated, and e.g. the injected industry volume can be redistributed between subsequent injections and / or the injection time can be changed for one or more subsequent injections, where the view can be taken to ev. restrictions with regard to e.g. minimum permitted length or industry quantity for an industry injection.

Instead of evaluating a number of specific injection schedules, the method may be arranged to perform e.g. The above calculations give a number of conceivable scenarios, where the calculations can be performed for different injection lengths / quantities / times for the different injections, with corresponding changes in released energy.

The more fuel injections performed during a combustion cycle, the more parameters can be changed. At an initial number of injections, the regulation can therefore be relatively complex, since an initial number of parameters can be varied and thus would need to be evaluated. For example. a very initial number of injections can be arranged to be performed during one and the same combustion cycle, such as a dozen, or even about a hundred injections.

In such situations, there may be several equivalent injection strategies, which result in essentially the same pressure mean. This introduces an undesirable complexity in the calculations.

According to one embodiment, a control is applied cidr the nearest injection / injection is considered as a separate injection, and subsequent industry injections as a single additional "virtual" 537 190 injection, whereby the heat losses can be optimized between these two injections. This is exemplified in Fig. 5A, where the injection 501 corresponds to inspi as above, the injection 502 corresponds to insp2 as above, and where the remaining injections 503-505 are treated as a single virtual injection 506. By proceeding in this way, the displacement that takes place between insp2 and subsequent injections are not specifically distributed between the injections 503-505, but are distributed at this stage between the injection 502 and the "virtual" injection 506, respectively.

After the injection 502 has been performed, the procedure is repeated as above with a new determination of the injection schedule to obtain the desired pressure average, but then with the injection 503 as a separate injection, see Fig. 5B, and the injection 504, 505 together constitute a virtual injection when distributed as above .

In Fig. 5A, the virtual injection 506 consists of three injections, but as will be appreciated, the virtual injection 506 may initially comprise more than three injections, such as 10 injections or 100 injections, depending on the number of injections intended to be performed. during the combustion cycle, the procedure being repeated until all the injections have been made.

It is also possible to use e.g. an MPC (Model Predictive Control) control when controlling according to the invention.

An example of an MPC control is shown in Fig. 6, where the reference curve 603 corresponds to the expected development of the pressure mean value during the combustion cycle, i.e. the result of eq. (6) with the pressure estimated as above. Curve 603 thus represents the development of the pressure average value that is sought during the combustion cycle. The specific appearance 31 537 190 for this development of pressure averages can advantageously be determined in advance, e.g. by applicable calculations and / or feeds on the motor type, whereby this data can be stored in the control system memory as a function of e.g. speed and load. This also means that the combustion does not have to be controlled solely against a pressure average value radiating as usual, but the combustion can also be arranged to be controlled towards a predetermined pressure medium development, such as e.g. curve 603 in Fig. 6, whereby habitual injection may have the purpose of resulting in a hitherto resulting pressure average which at any given time amounts to the corresponding point on curve 603.

The solid curve 602 up to time k represents the actual pressure mean which has hitherto arisen and which has been calculated as above with the aid of actual data from the crank angle-resolved pressure sensor. Curve 601 represents the predicted development of the pressure mean value based on the predicted injection profile, and thus constitutes the pressure mean value development that is expected. Dashed injections 605, 606, 607 represent the predicted control signal, i.e. the expected injection profile is applied, and 608, 609 represent already challenging injections.

The predicted injection profile is updated at appropriate intervals, such as e.g. as usual challenge injection, in order to reach the final value which is sought after and which is given by the reference screw 603, and where the next injection is determined based on radiating ratio in relation to the estimated mean pressure development.

Thus, the present invention provides a method which allows a very good control of a combustion process, and which adapts the combustion during pagan combustion to obtain a very accurate control of the torque delivered.

According to the above, straightened work can thus be estimated for a number of different alternative injection schedules for the remaining injections, whereby an injection schedule that results in the work requested can be selected when performing subsequent injection. In cases where several injection schemes / control alternatives meet the set conditions, other parameters can be used to select which of these is to be used. There may also be other reasons to simultaneously regulate even based on other parameters. For example. In addition to based on work performed, injection molding can also be selected in part based on one or more of the perspectives pressure amplitude, heat loss, exhaust temperature, pressure change rate, or nitrogen oxides generated during combustion as additional criteria where such determination can be performed according to any of the parallel patent applications listed below.

Specifically, the parallel application "PROCEDURE AND SYSTEM FOR REGULATING AN COMBUSTION ENGINE V" (Swedish patent application, application number: 1350508-6) shows a procedure for regulating subsequent combustion based on an estimated maximum pressure amplitude.

Furthermore, the parallel application "PROCEDURE AND SYSTEM FOR REGULATING AN COMBUSTION ENGINE II" (Swedish patent application, application number: 1350507-8) shows a method for regulating a subsequent part of combustion during a first combustion cycle during said first combustion cycle. subsequent combustion resulting temperature. 33 537 190 Furthermore, the parallel application "PROCEDURE AND SYSTEM FOR REGULATING AN COMBUSTION ENGINE I" (Swedish patent application, application number: 1350506-0) shows a procedure for regulating subsequent combustion based on an estimated maximum pressure change rate.

Furthermore, the parallel application "PROCEDURE AND SYSTEM FOR CONTROLING AN COMBUSTION ENGINE IV" discloses a method for controlling combustion during a first combustion cycle during a subsequent part of said first combustion cycle with respect to a representation of a heat loss resulting from said combustion.

Furthermore, the parallel application "PROCEDURE AND SYSTEM FOR CONTROLING AN COMBUSTION ENGINE VI" shows a method for estimating during a first combustion cycle a first mat of nitrogen oxides resulting from combustion during said first combustion cycle, and based on said first mat, regulating combustion during combustion. part of the said first combustion cycle.

The invention has been exemplified above in a manner in which a pressure sensor 206 is used to determine a pressure in the combustion chamber, and by means of which pressure the heat losses can then be estimated. As an alternative to using pressure sensors, one (or more) other sensors can be used instead, such as e.g. high-resolution ion current sensors, knock sensors or strain gauges, whereby the pressure in the combustion chamber can be modeled by using sensor signals from such sensors. It is also possible to combine different types of sensors, e.g. to obtain a more accurate estimation of the pressure in the combustion chamber, and / or to use other applicable sensors, where the sensor signals are converted to the corresponding pressure for use in control as above.

Furthermore, in the above description, only industry injection has been regulated. Instead of only regulating the amount of fuel supplied, the pressure average value during combustion can be arranged to be regulated with the aid of e.g. exhaust valves, whereby injection can be carried out according to a predetermined schedule, but where the exhaust valves are used to, if necessary, e.g. lower the pressure in the combustion chamber and thus also the pressure average.

Furthermore, the control can be performed with any applicable type of regulator, or e.g. with the help of state models and state feedback (eg line programming, the LQG method or similar).

The process according to the invention for controlling the internal combustion engine can also be combined with sensor signals from other sensor systems where resolution at the crank angle level is not available, such as e.g. other pressure sensors, NOx sensors, NH3 sensors, PM sensors, oxygen sensors and / or temperature sensors etc., which input signals e.g. can be used as input parameters when estimating e.g. heat losses through the use of data-driven models instead of models of the type described above.

Furthermore, the present invention has been exemplified above in connection with vehicles. However, the invention is also applicable to arbitrary vessels / processes where combustion control as above is applicable, such as e.g. water or aircraft with combustion processes as above.

It should also be noted that the system may be modified according to various embodiments of the method of the invention (and vice versa) and that the present invention is in no way limited to the above-described embodiments of the method of the invention, but relates to and includes all embodiments of the invention. attached scope of independent requirements protection. 36

Claims (30)

A method of controlling an internal combustion engine (101), said combustion engine (101) comprising at least one combustion chamber (201) and means (202) for supplying fuel to said combustion chamber (201), said combustion in said combustion chamber (101). 201) takes place in combustion cycles, the process being characterized in that: 1. during a first part of a first combustion cycle, by means of a first sensor means determining a first parameter value representing a quantity in combustion in said combustion chamber (201), and 2. based on said first parameter value, regulating combustion during a subsequent part of said combustion chamber; first combustion cycle, wherein in said regulation the combustion during said subsequent part of said first combustion cycle is regulated with respect to a work done during combustion, whereby a representation of a work resulting hitherto under said first combustion cycle is estimated, and 3. wherein said subsequent combustion part of said combustion regulated based on said representation of said work so far during said first combustion cycle work. A method according to claim 1, wherein the work performed in said combustion is represented by an average pressure during said combustion cycle. A method according to any one of claims 1-2, further comprising, based on said first parameter value, determining control parameters for controlling the combustion during said subsequent part of said first combustion cycle. A method according to any one of claims 1-3, wherein, in said regulation with respect to the work performed during the combustion, the combustion is regulated against a first average pressure corresponding to said performed work during said combustion cycle. A method according to any one of claims 1-4, further comprising: - determining an exhausted work requested for said combustion cycle, and - regulating the combustion during said subsequent part of said first combustion cycle against said requested exhausted work. A method according to any one of claims 1-5, further comprising: - regulating the combustion during said subsequent part of said first combustion cycle based on a comparison between said estimated expected work and an exhausted work requested during said combustion cycle. The method of claim 3, further comprising in said determining control parameters for said subsequent portion of said combustion cycle, using said first parameter, estimating a expected pressure change during said subsequent portion of said combustion cycle. A method according to any one of the preceding claims, wherein in said regulation an expected work during said combustion cycle is estimated, wherein said expected 38 537 190 work is estimated by using an estimation of a heat release during said combustion. A method according to claim 8, wherein in estimating said expected work done, a pressure change during said remaining part of said combustion cycle is estimated by using said estimating a heat release during said combustion. A method according to any one of the preceding claims, wherein said first parameter value represents a pressure during said first combustion cycle in said combustion chamber (201). A method according to any one of the preceding claims, further comprising controlling combustion during said uncomplicated part of said first combustion cycle by regulating fuel for supply to said combustion chamber (201). A method according to any one of the preceding claims, further comprising, in said regulating said combustion during said subsequent part of said combustion, establishing a predetermined work done during said combustion cycle for a plurality of control alternatives, and - from said plurality of control alternatives, selecting a control alternative for regulation of said Uncomplicated part of said combustion cycle. A method according to any one of the preceding claims, further comprising: - in said regulation, evaluating at least the first and a second regulation alternative, respectively, wherein it is said of the first and second regulation alternatives, respectively, that 39 537 190 are expected to result in a desired work done. A method according to claim 12 or 13, wherein said control alternative consists of alternatives for supplying fuel for at least one fuel supply during said subsequent part of said combustion cycle. A method according to any one of claims 11-14, wherein the fuel for supply to said combustion chamber (201) is regulated by controlling fuel injection by means of at least one fuel injector (202). A method according to any one of claims 11-15, wherein At least one fuel injection is performed during said subsequent part of said combustion cycle, wherein an amount of fuel and / or injection time and / or injection length is regulated for said fuel injection. A method according to any one of claims 11-16, wherein at least two injections of fuel are performed during said uncomplicated part of said combustion cycle, wherein a remaining part of said combustion is regulated at least after said first of said at least two injections of fuel. A method according to any one of claims 11-17, wherein in controlling said combustion at least three injections are performed during said subsequent part of said combustion process, wherein in determining control parameters for a first of said at least three injections, remaining injections are treated as a single aggregate injection in the said regulation. A method according to any one of claims 11-18, wherein controlling combustion during said subsequent part of said first combustion cycle is performed at least in part by controlling fuel for injection into said combustion chamber (201) during an ongoing fuel injection. A method according to any one of claims 11-19, further comprising, when regulating fuel for injection to said combustion chamber (201), changing a distribution of fuel quantities between at least two fuel injections. 10 A method according to any preceding claim, further comprising performing a first fuel injection to said combustion chamber (201) during said first part of said first combustion cycle, and At least a second fuel injection during said subsequent part of said combustion cycle, wherein control parameters for said second fuel combustion parameters determined after the said first industry injection. A method according to any preceding claim, further comprising controlling combustion during said subsequent portion of said first combustion cycle by controlling one or more valves operating at said combustion chamber (201). A method according to any one of the preceding claims, wherein said control is performed for a plurality of consecutive combustion cycles. A method according to any one of the preceding claims, wherein said first parameter value regarding a quantity in combustion in said combustion chamber (201) is determined at least at habit crank angle, habit tenth of habit crank angle or every hundredth of habit crank angle. 41 537 190 A method according to any one of the preceding claims, wherein said first parameter was determined by using one or more of the group: cylinder pressure sensor, knock sensor, strain sensor, speed sensor, ion current sensor. A computer program comprising program code, which when said program code is executed in a computer causes said computer to perform the procedure according to any of claims 1-25. A computer program product comprising a computer readable medium and a computer program according to claim 26, wherein said computer program is included in said computer readable medium. A system for controlling an internal combustion engine (101), said combustion engine (101) comprising at least one combustion chamber (201) and means (202) for supplying fuel to said combustion chamber (201), wherein combustion takes place in said combustion chamber (201). in combustion cycles, characterized in that the system comprises means (115) for: 1. during a first part of a first combustion cycle, by means of a first sensor means determining a first parameter value representing a quantity in combustion in said combustion chamber (201), and 2 based on said first parameter value, regulate combustion during a subsequent part of said first combustion cycle, wherein in said control the combustion during said subsequent part of said first combustion cycle is regulated with respect to a work performed by the combustion, wherein a representation of a hitherto combustion cycle resulting work is estimated, and - whereby namnd the subsequent part of the said combustion cycle is regulated based on the said work resulting so far during said first combustion cycle work. System according to claim 28, characterized in that said internal combustion engine consists of flakes from the group: vehicle engine, marine engine, industrial engine. Vehicle (100), characterized in that it comprises a system according to claim 28 or 29. 43