DE112014001724B4 - Method and system for controlling an internal combustion engine - Google Patents

Abstract

Method for controlling an internal combustion engine (101), the internal combustion engine (101) comprising at least one combustion chamber (201) and elements (202) for supplying fuel to the combustion chamber (201), the combustion in the combustion chamber (201) taking place in combustion cycles, the method being characterized in that: during a first part of a first combustion cycle with a first sensor element (206) a first parameter value is determined which represents a physical quantity for the combustion in the combustion chamber (201), - on the basis of the first Parameter value, the combustion is controlled during a subsequent part of the first combustion stroke, so that the controller controls the combustion during the following part of the first combustion stroke with respect to a resulting temperature in the subsequent combustion, - based on the first parameter value, estimating one Representation of a temperature (T) un during combustion d / or temperature change during the following part of the first combustion stroke after the first part of the first combustion stroke, and - based on the estimated resulting temperature (T) and / or temperature change, controlling the combustion during the following part of the first combustion stroke.

Description

Field of the Invention

The present invention relates to internal combustion engines and in particular to a method for controlling an internal combustion engine according to the introduction to claim 1. The present invention also relates to a system 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

As pollution and air quality play an increasingly important role for the state, emission standards and guidelines for exhaust gases from internal combustion engines have been issued in many countries.

These emission guidelines often consist of requirements that define permitted limits for exhaust emissions from vehicles with internal combustion engines. For example, there are often regulations for nitrogen oxides (NO _x ), hydrocarbons (KW) and carbon monoxide (CO). These emission guidelines can also include the presence of particles in exhaust emissions, for example.

In order to comply with these emission guidelines, the exhaust gases generated by the combustion of the internal combustion engine are treated (cleaned). For example, a so-called catalytic cleaning process can be used, so that exhaust gas cleaning systems in, for example, vehicles and other means of transportation usually comprise one or more catalysts and / or other components. For example, the exhaust gas treatment systems in vehicles with a diesel engine often include particle filters.

The occurrence of undesirable substances in the exhaust gas flow from the internal combustion engine is caused to a large extent by the combustion process in the combustion chamber of the internal combustion engine, at least in part depending on the amount of fuel consumed in the combustion. For this reason and because the economy of heavy goods vehicles in particular depends on the amount of fuel consumed, great efforts are being made to make the combustion of internal combustion engines more efficient in order to reduce emissions and fuel consumption.

document DE 100 32 232 A1 discloses a compression ignition engine and a control method thereof in which a cold flame is generated prior to the combustion of the fuel in the combustion chamber. In order to generate a cold flame, it may be necessary to raise the initial temperature of the mixture. A cylinder internal pressure and a cylinder temperature before the start of compression are estimated by a cylinder internal state estimation model and compared with a target cylinder internal state. The difference is corrected by controlling the exhaust gas recirculation.

document DE 11 2008 000 687 T5 discloses a pressure or noise sensor within or near a combustion chamber. If an expected pressure or noise does not occur during the combustion process, the injection of the fuel can be adjusted so that the pressure or the noise is guided towards the desired values during the rest of the ongoing combustion process.

document DE 10 2008 000 012 A1 discloses a burn rate determiner that determines a burn rate through a repeated experimental trial and error process. This corresponds to the ratio of the target heat generation amount, which is an estimated ideal heat amount to be generated by a fuel supply, and an actual heat generation amount of the supplied fuel.

document DE 10 2006 044 866 A1 discloses a method and an apparatus wherein an injection signal is generated for an injector. Data of the current operating point are read from a setpoint map, corrected by data from a correction map and converted into the injection signal by an A / D converter, so that an injector makes a first injection of fuel into the combustion chamber. The actual value of the start of burning is compared with the setpoint map and a deviation is added to the correction map. The data can now be used for a later injection process.

Summary of the invention

An object of the present invention is to provide a method for controlling an internal combustion engine. This object is achieved with a method according to claim 1. Furthermore, it is an object of the invention to provide a system for controlling an internal combustion engine. This object is achieved by a system according to claim 35. Furthermore, it is an object of the invention to provide a computer program. This object is achieved by a computer program according to claim 33. It is also an object to provide a computer program product. This object is achieved by a computer program product according to claim 34. In addition, it is an object of the invention to provide a vehicle. This object is achieved by a vehicle according to claim 37.

The present invention relates to a method for controlling an internal combustion engine, the internal combustion engine comprising at least one combustion chamber and elements for supplying fuel to the combustion chamber, the combustion in the combustion chamber taking place in combustion cycles.

• - auf der Basis des ersten Parameterwerts wird die Verbrennung während des folgenden Teils des ersten Verbrennungstakts gesteuert, wobei während der Steuerung die Verbrennung während des folgenden Teils des ersten Verbrennungstakts in Bezug auf eine Darstellung einer resultierenden Temperatur bei der folgenden Verbrennung wie der Temperatur bei EVO, das heißt einem Öffnen der Abgasventile nach der Verbrennung während des Verbrennungstakts gesteuert wird.

During a first part of a first combustion cycle, a first parameter value is determined with a first sensor element, which parameter represents a physical quantity in relation to the combustion in the combustion chamber, and

• on the basis of the first parameter value, the combustion is controlled during the following part of the first combustion stroke, wherein during the control the combustion during the following part of the first combustion stroke with respect to a representation of a resultant temperature in the following combustion like the temperature in EVO, that is, an opening of the exhaust valves after the combustion is controlled during the combustion stroke.

As previously mentioned, the efficiency of the internal combustion engine has a strong impact on the overall economy of the vehicle, especially in heavy-duty vehicles. For this reason, it is often desirable to control combustion in a manner that ensures combustion is as efficient as possible.

In addition, the combustion of the internal combustion engine can be controlled in relation to the desired exhaust gas characteristics during the treatment in the following exhaust system. For example, the ignition timing and / or the amount of fuel injected can be controlled in order to influence the course of the combustion and thus the temperature and / or the composition of the exhaust gas flow. For example, in certain cases, a higher exhaust gas temperature may be desirable at the expense of the efficiency of the internal combustion engine in order to achieve a desired function of one or more components of the aftertreatment system. It may also be the case that the overall efficiency, including exhaust gas aftertreatment, can also be improved in the event of a deterioration in the efficiency of the internal combustion engine, for example due to the lower consumption of reducing agent, for example urea, with the disadvantage of an increased fuel supply. In certain situations, deterioration in overall efficiency may also be acceptable, for example to achieve a desired condition in the aftertreatment system.

The present invention relates to controlling the combustion process, wherein an ongoing progress of the combustion stroke can be controlled during the ongoing combustion to achieve a desired result of the combustion. In particular, the progress of the combustion is controlled with respect to a resulting temperature during the combustion. This resulting temperature can consist of a resulting average temperature of the gas in the combustion chamber at the end of the combustion cycle. The control according to the present invention can be achieved during a first part of a combustion cycle by determining a parameter value, which represents a physical quantity during the combustion, for example a pressure prevailing in the combustion chamber.

Based on this parameter value, for example the prevailing pressure, the combustion is then controlled during a subsequent part of the combustion stroke, so that the combustion is controlled in relation to a temperature for the combustion process.

This procedure allows the desired exhaust gas and / or combustion characteristics to be achieved during the combustion. For example, it may be desirable for the exhaust gas temperature to have a certain value when leaving the engine. The combustion can thus be controlled to a desired resulting exhaust gas temperature at the time the exhaust valves are opened, so that an exhaust gas flow with a very precise and desired temperature can be achieved. This can be desirable, for example, in order to achieve desired features such as a desired temperature and / or desired chemical reactions in exhaust gas treatment components of the exhaust system.

For example, a relationship between a corresponding component in the aftertreatment system, for example an SCR catalytic converter, and the temperature of the exhaust gas flow when leaving the cylinder can be determined, so that an association can be made with respect to the temperature change in the exhaust gas flow from the cylinder, for example, to the SCR catalytic converter and the assignment can be used to determine a desired exhaust gas temperature resulting during the combustion, which is then likely to lead to a desired temperature, for example on the SCR catalytic converter. Alternatively, for example, a table with, for example, the ambient temperature, one or more temperatures in the aftertreatment system and a resulting temperature during the combustion can be used, so that a reference value during the combustion can be determined by querying the table.

Alternatively, the combustion stroke may be controlled in relation to the temperature change that the combustion process undergoes during combustion, that is, the combustion is controlled based on the change in the combustion chamber temperature during the combustion, that is, not exclusively toward a final temperature, and may for example within the scope of what is possible to maintain a suitable temperature curve, so that this temperature change is controlled by influencing the combustion during an ongoing combustion cycle, so that a desired temperature change is achieved during the combustion. The regulation can be controlled in the direction of an empirically or otherwise determined temperature curve which is likely to lead to desired features, for example in relation to emissions or other features.

By controlling the temperature change during combustion, the composition of the exhaust gas flow can be controlled so that the presence of the various substances that normally occur in the exhaust gas flow is influenced in a desired direction, for example depending on the desired composition on one or more exhaust gas treatment components in the exhaust system , By controlling the temperature change, emissions can also be reduced. The control according to the present invention can be used, for example, to reduce undesirable exhaust gas emissions. By executing the control action during an ongoing combustion cycle, the combustion can be influenced to a greater extent compared to executing the control action solely on the basis of previous combustion cycles.

During a control action according to the invention, a representation of a resulting temperature and / or temperature change can be predicted by an estimate for the following part of the first combustion stroke on the basis of the first parameter value. The subsequent combustion can then be controlled based on the representation of the estimated temperature and / or temperature change. The temperature development for the following part of the combustion cycle can thus be predicted by an estimate, the first parameter value making a good estimate possible, since the estimate is carried out using initial values which consist of the prevailing conditions in the combustion chamber after the start of the combustion cycle.

According to one embodiment, the first parameter value is determined when the combustion has started in the first combustion chamber, so that the combustion can be regulated during the following part of the first combustion cycle on the basis of the conditions prevailing in the combustion chamber after the start of fuel combustion. The first parameter value thus forms a representation of an actually prevailing relationship for the physical quantity at a point in time / in a crank angle position when the first combustion cycle has started. The temperature / temperature change can be estimated, for example, by estimating the pressure change in the combustion chamber during the first part of the combustion cycle.

The control of the combustion may also be arranged to be performed individually for each cylinder, and it is also possible to control combustion during a subsequent combustion stroke based on information from one or more previous combustion processes.

This type of control offers the advantage that, for example, differences between different cylinders can be recognized and shifted with an individual adjustment of parameters for a specific cylinder, such as the opening time of the injection nozzle. However, different control actions for different cylinders may be desirable, for example to control certain cylinders in the direction of fulfilling a certain criterion and other cylinders in the direction of other corresponding criteria, which can also be achieved according to the invention. Furthermore, one or more of the cylinders arranged for control according to the invention, while the combustion in the remaining cylinders can be carried out in a conventional or other corresponding manner.

The method according to the present invention can be implemented, for example, by one or more field programmable gate array (FPGA) circuits and / or one or more application-specific integrated circuits (ASIC) or other types of circuits that provide the offer desired computing speed, can be implemented.

Further features and advantages of the present invention are set forth in the following detailed description of exemplary embodiments and in the accompanying drawings.

• 1A zeigt schematisch ein Fahrzeug, in dem die vorliegende Erfindung verwendet werden kann.
• 1B zeigt ein Steuergerät in der Steuerung für das in 1A dargestellte Fahrzeug.
• 2 zeigt den Verbrennungsmotor im Fahrzeug, das in 1A detaillierter dargestellt ist.
• 3 zeigt eine beispielhafte Ausführungsform gemäß der vorliegenden Erfindung.
• 4 zeigt ein Beispiel für eine geschätzte Temperaturkurve einer Verbrennung.
• 5A-B zeigt ein Beispiel für eine Regelung in Situationen mit mehr als drei Einspritzungen.
• 6 zeigt ein Beispiel für eine MPC.

Brief description of the drawings

• 1A shows schematically a vehicle in which the present invention can be used.
• 1B shows a control unit in the controller for the in 1A shown vehicle.
• 2 shows the internal combustion engine in the vehicle, which in 1A is shown in more detail.
• 3 shows an exemplary embodiment according to the present invention.
• 4 shows an example of an estimated temperature curve of a combustion.
• 5A-B shows an example of a control in situations with more than three injections.
• 6 shows an example of an MPC.

Detailed description of the embodiments

1A schematically shows a drive train in a vehicle 100 according to an embodiment of the present invention. The drive train includes an internal combustion engine 101 , which in a conventional manner via an output shaft on the internal combustion engine 101 , usually via a flywheel 102 , via a clutch 106 with a gear 103 connected is.

The internal combustion engine 101 is controlled by the engine via a control unit 115 controlled. Likewise, the clutch 106 , which can consist, for example, of an automatically controlled clutch, as well as the transmission 103 controlled by the control of the vehicle with one or more corresponding control devices (not shown). The drive train of the vehicle can also have a different design and can comprise, for example, a conventional automatic transmission or a manual transmission.

An output shaft 107 from the gearbox 103 drives the drive wheels 113 . 114 in a conventional way via the axle drives and the drive axles 104 . 105 on. 1A shows only one axle with drive wheels 113 . 114 , but in a conventional manner, the vehicle may include more than one axle equipped with drive wheels or one or more additional axles such as one or more support axles. The vehicle 100 also includes an exhaust system with an aftertreatment system 200 for the conventional treatment (cleaning) of exhaust emissions from combustion in the combustion chamber (i.e. cylinders) of the internal combustion engine 101 ,

The aftertreatment system often includes a form of catalytic cleaning process using one or more catalysts to purify the exhaust gases. Vehicles with diesel engines often also include a diesel particle filter (DPF) in order to collect soot particles formed during the combustion of fuel in the combustion chamber of the internal combustion engine. Aftertreatment systems in vehicles of the type shown can further comprise a diesel oxidation catalyst (DOC). The diesel oxidation catalyst has multiple functions and is typically used in the aftertreatment to oxidize hydrocarbon and carbon monoxide residues in the exhaust gas stream to carbon dioxide and water. The oxidation catalyst can, for example, also oxidize nitrogen oxide (NO) to nitrogen dioxide (NO ₂ ). An aftertreatment system can also have more components than previously shown, but can also include fewer components. For example, the aftertreatment system 200 comprise an SCR (Selective Catalytic Reduction) catalyst arranged downstream of the particle filter. SCR catalysts use ammonia (NH ₃ ) or a compound from which ammonia can be generated / as an additive to reduce the amount of nitrogen oxides NO _x in the exhaust gas stream.

Furthermore, internal combustion engines in vehicles of the in 1A Often shown type equipped with controllable injection nozzles to supply the desired amount of fuel at the desired time in the combustion cycle, such as at a certain piston position (crank angle degree) in the case of a piston engine, to the combustion chamber of the internal combustion engine.

2 shows schematically an example of a fuel injection for the in 1A illustrated internal combustion engine 101 , The fuel injection consists of a so-called common rail system; however, the invention can also be applied to other types of injections. 2 shows only one cylinder / one combustion chamber 201 with a piston acting in the cylinder 203 ; 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 chambers, for example any number of cylinders / combustion chambers in the range from 1 to 20 or even more. The internal combustion engine also comprises at least one respective injection nozzle 202 for every combustion chamber (every cylinder) 201 , Each respective injection nozzle is thus used to inject (supply) fuel into a respective combustion chamber 201 used. Alternatively, two or more injection nozzles can be used per combustion chamber. The injectors 202 are individually controlled by respective actuators (not shown) arranged on the respective injection nozzles, based on the control signals received, for example by the control unit 115 the opening / closing of the injection nozzles 202 Taxes.

The control signals for controlling the opening / closing of the injectors 202 by the actuators by a corresponding control unit as in this case from the engine control unit 115 be generated. The engine control unit 115 thus determines the amount of fuel to be injected at a certain point in time, for example on the basis of the prevailing operating conditions in the vehicle 100 , In the 2 The injection shown thus consists of a so-called common rail system, which means that all injection nozzles (and thus all combustion chambers) are made from a common fuel line 204 (Common Rail) fueled by a fuel pump 205 is filled with fuel from a fuel tank (not shown) while at the same time the fuel in the line 204 also by the fuel pump 205 is exposed to a certain pressure. The highly pressurized fuel in the common line 204 is then in the combustion chamber 201 of the internal combustion engine 101 sprayed when the respective injector 202 is opened. Multiple opening / closing of a particular injector can take place during the same combustion cycle, so that several injections can be carried out during the combustion from one combustion cycle. Furthermore, each combustion chamber is equipped with a respective pressure sensor 206 for sending signals relating to a pressure prevailing in the combustion chamber, for example to the control unit 115 fitted. The pressure sensor can, for example, be piezo-based and must be fast enough to send pressure signals resolved according to the crank angle, for example after the tenth or fifth or after each crank angle degree or in another suitable interval, for example more frequently.

With a system like the one in 2 shown, combustion during a combustion stroke in a combustion chamber can be controlled to a large extent, for example by using multiple injections, the times and / or the duration for the respective injections being able to be controlled, and data being, for example, from the pressure sensors 206 can be taken into account in relation to this control action. According to the present invention, for example, times and / or duration of injections and / or injected fuel quantities during the ongoing combustion based on data from the ongoing combustion with the aim of controlling the combustion with respect to a temperature that prevails during the combustion, and / or a resulting temperature can be adjusted. 3 shows an example method 300 according to the present invention, the method according to the present example for performing the in 1A-B engine control unit shown 115 is arranged.

In general, controls in modern vehicles consist of a communication bus system that has one or more communication buses for connecting a number of electronic control devices, such as the control device or the controller 115 and various components arranged in the vehicle. According to the prior art, such a control can comprise a large number of control devices and the responsibility for a specific function can be divided between several control devices.

To simplify the show 1A-B only the control unit 115 in which the present invention is implemented in the illustrated embodiment. However, the invention can also be implemented in a control device specifically provided for the present invention or completely or partially in one or more other control devices which are already present in the vehicle. Considering In terms of the speed at which calculations according to the present invention are carried out, the invention can be arranged for implementation in a control unit which is specially adapted to real-time calculations of the type described below. The implementation of the present invention has shown that, for example, ASIC and FPGA solutions are suitable for calculations according to the present invention and manage them well.

The function of the control unit 115 (or the control device (s) in which the present invention is implemented) according to the present invention can apart from sensor signals from the pressure sensors 202 depend, for example, on signals from other control units or sensors. In general, control devices of the type shown are normally arranged to receive sensor signals from different parts of the vehicle and from various control devices arranged in the vehicle.

The control is often controlled by programmed instructions. These programmed instructions typically consist of a computer program which, when executed on a computer or in a control device, causes the computer / control device to execute the desired control action as a method step in the process according to the present invention.

The computer program usually consists of a computer program product, the computer program product being a corresponding storage medium 121 (please refer 1B) includes and the computer program on the storage medium 121 is saved. The digital storage medium 121 For example, it can consist of an element from the following group: ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable PROM), Flash, EEPROM (Electrically Erasable PROM), hard disk unit, etc., and can be in Control device or in combination with this, wherein the computer program is executed by the control device. The behavior of the vehicle in a specific situation can thus be adapted by changing the instructions of the computer program.

An example control unit (control unit 115 ) is schematically in 1B shown and the control unit can in turn a computing unit 120 comprise, in turn, for example, from a suitable type of processor or microcomputer, for example a digital signal processor (DSP) circuit, one or more FPGA (field programmable gate array) circuits or one or more circuits with a specified specific function (Application Specific Integrated Circuit, ASIC) can exist. The computing unit 120 is with a storage unit 121 connected which is the control unit 120 for example supplied with the stored program code and / or the stored data which the computing unit 120 to perform calculations. The computing unit 120 is also used to store intermediate or final results of calculations in the storage unit 121 educated.

Furthermore, the control device with devices 122 . 123 . 124 . 125 equipped for receiving and sending input and output signals. These input and output signals can include waveforms, pulses, or other attributes generated by the devices 122 . 125 for receiving input signals as information for processing by the computing unit 120 can be recognized. The devices 123 . 124 for sending output signals are for converting the calculation result from the computing unit 120 arranged in output signals for transmission to other parts of the control of the vehicle 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 can consist of one or more elements from the following group: cable, data bus such as a CAN (controller area network) bus, MOST (media-oriented) -Systems-Transport-) bus or other bus configuration or wireless connection.

Regarding the in 3 procedures shown 300 the process begins at step 301 , in which it is determined whether the combustion process should be controlled according to the invention. The controller according to the invention can for example be arranged for continuous execution as soon as the internal combustion engine 101 is started. Alternatively, the control action can be arranged to execute, for example, while the combustion of the internal combustion engine is not to be controlled according to another criterion. For example, there may be situations in which it is desirable that the control action be based on factors other than primarily the temperature of the combustion. According to one embodiment, the combustion is controlled simultaneously with respect to the temperature of the combustion and at least one additional control parameter. For example, weighing can take place, wherein the prioritization of the control parameters can be arranged in order to fulfill a desired control result, for example for control purposes, according to a suitable cost function.

The method according to the present invention thus consists of a method for controlling the internal combustion engine 101 while burning in the combustion chamber 201 takes place in combustion cycles. In the prior art, the term "combustion stroke" is defined as the steps involved in combustion in an internal combustion engine, that is, the two strokes of a two-stroke engine and the four strokes of a four-stroke engine. The term also includes cycles in which no fuel is effectively injected, but the internal combustion engine is still running at a certain engine speed, for example through the drive wheels of the vehicle via the drive train, for example when towing. This means that even if no fuel is injected, a combustion cycle is carried out, for example, every two revolutions (in the case of four-stroke engines) or, for example, after each revolution (in the case of two-stroke engines) about which the output shaft of the internal combustion engine rotates. The same applies to other types of internal combustion engines.

In step 302 it is determined whether a combustion stroke has started or will, and if so, the method moves to step 303 continues while a parameter i for representing an injection number is set to one.

In step 303 an injection sequence is determined which is likely to lead to a desired temperature during the combustion, for example an injection sequence which is likely to lead to a desired end temperature or is likely to result in a desired temperature curve during the combustion of the combustion stroke.

In general, the supply of fuel is normally defined in advance in terms of both the quantity and the manner of supply, i.e. in one or more fuel injections to be carried out during the combustion stroke, for example according to the work (torque) that the internal combustion engine must perform during the combustion cycle, since according to the prior art there is no change in the specific injection sequence during an ongoing combustion cycle. Predefined injection sequences can be present, for example, in tables in the control of the vehicle for a large number of operating modes, such as different engine speeds, different requested work, different combustion air pressures, etc., the tabular data, for example, by corresponding tests / measurements during, for example, the development of the internal combustion engine and / or Vehicle can be created so that the corresponding injection sequence can be selected on the basis of the prevailing conditions, and the injection sequence can be selected, for example, on the basis of a desire for how the temperature in the combustion chamber should change.

These injection sequences can consist of the number of injections and features in the form of, for example, time (crank angle position) at the start of injection, duration of injection, injection pressure etc. and can thus be stored in the control of the vehicle for a large number of operating modes and, for example, with the Target to result in a certain exhaust gas temperature can be calculated / measured.

According to one embodiment of the invention, an injection sequence is determined with corresponding calculations before the start of combustion, for example as explained below, for example the required work performed, the required exhaust gas temperature, the required emissions (for example high / low NO _x content) parameters in the calculations can represent, as well as, for example, the required end temperature for the exhaust gases, as in one embodiment of the invention.

According to the present embodiment, such a predetermined injection sequence in step 303 applied, wherein this predetermined injection sequence is selected on the basis of the prevailing condition of the work required by the internal combustion engine, for example with a table call. According to one embodiment, a desired exhaust gas temperature can also represent a parameter in the selection of an injection sequence, so that different injection sequences can be defined if different temperature developments are expected in the combustion, for example while the same work is being carried out on the output shaft of the internal combustion engine.

According to one embodiment, a desired temperature does not have to be selected in the selection of an injection sequence in step 303 may be included, but the temperature parameter may be arranged for application only during the control action after a first injection or a first part of an injection is completed.

According to one embodiment, the injection sequence is determined entirely in accordance with, for example, the calculations shown below, with different injection sequences in advance for example with each other in step 303 can be compared in order to determine a most preferred injection sequence, thus before a first fuel injection takes place; but in the calculation example explained below, the calculations are only applied after the start of an injection in the combustion cycle. Since specific assumed conditions presumably lead to the same preferred injection sequence each time, it may be advantageous to select an injection sequence by a type of call before a combustion cycle and thus to reduce the calculation load, so that the calculation, as explained below, therefore only after the start of the injection he follows. In addition to the following example of how to determine the injection sequence, other models with a similar function can alternatively be used.

The target temperature T _targetEvo Desired for the exhaust gases when the exhaust valves are opened and the exhaust gases flow to the exhaust system and which can control the choice of an injection sequence can be determined in a suitable manner. As explained above, a relationship can be determined, for example, between the temperature of the exhaust gas flow at a corresponding component in the aftertreatment system and the temperature of the exhaust gas flow at the outlet of the cylinder, so that T _targetEvo can be determined on the basis of a certain desired temperature in the aftertreatment system. Alternatively, for example T _targetEvo be controlled on the basis of signals from one or more temperature sensors in the aftertreatment system. T _targetEvo For example, it can also be arranged to be controlled by empirical data, measurements possibly being carried out beforehand and, for example, exhaust gas emissions or other parameters being measured, and advantageous combustion chamber temperatures being measured and then being able to be fed to the control of the vehicle, so that reference values are obtained during combustion a table call or other suitable way. As explained below, according to one embodiment, not only is a final temperature T _targetEvo is determined, but a preferred temperature curve can also be determined, for example, on the basis of empirical data, the control action then being carried out in relation to this determined temperature curve.

According to the present embodiment, in step 303 thus a predetermined injection sequence is determined at the start of the combustion cycle, the control action according to the invention being carried out only after the start of fuel injection during a combustion cycle, for example only after the at least one injection has been completed during the combustion cycle or at least after the start of an injection.

The fuel injection is thus normally carried out according to a predetermined sequence, and a plurality of injections can be arranged in order to be carried out during the same combustion stroke. As a result, the injections can be relatively short. For example, there are injection systems with 5 to 10 fuel injections / combustion; however, the number of fuel injections during a combustion stroke can be significantly larger, for example in the range of 100 fuel injections. The number of possible injections is controlled by the speed of the elements with which the injection is carried out, that is, in the case of a common rail system, by the speed at which the injection nozzles open and close.

According to the present example, at least three fuel injections insp _{1 are} carried out during the same combustion stroke; but, as previously explained, a larger number of injections and only one or two can be arranged for execution.

The injection sequence is thus determined in advance in the present example in order to achieve a specific exhaust gas temperature or solely on the basis of the desired work achieved. Then a first injection insp ₁ executed and in step 304 it is determined whether the first injection insp _{1 has been} carried out and, if so, the method goes to step 305 in which it is determined whether all injections i have been carried out. Since this is not the case in the present example, the method moves to step 306 continues while i is incremented by one for the next injection. In step 306 the pressure prevailing in the combustion chamber with the pressure sensor 206 determined. Furthermore, with the pressure sensor 206 the pressure prevailing in the combustion chamber is determined essentially continuously, approximately at appropriate intervals, for example every 0.1 to 10 crank angle degrees.

The combustion process can generally be described as the change in pressure in the combustion chamber that the combustion generates. The pressure change during a combustion cycle can be represented by a pressure curve, that is to say a representation of how the pressure in the combustion chamber changes during the combustion. As long as the combustion continues as expected, the pressure in the combustion chamber corresponds to the originally expected or estimated pressure. The temperature depends as described below directly together with the pressure in the combustion chamber, i.e. as soon as the pressure deviates from the estimated pressure, the temperature also deviates from the expected / estimated temperature. In addition, the combustion is influenced during the following part of the combustion cycle and thus the temperature development.

In step 306 is the pressure P _fΘ1 in the combustion chamber 201 for a given crank angle degree value Θ ₁ (please refer 4 ) with the pressure sensor 206 determined and in step 307 an expected resulting exhaust gas temperature is estimated during and / or at the end of combustion of the combustion stroke as described above, for example in the form of an estimate of the exhaust gas temperature at the time the exhaust valve is opened T _EVO (EVO = Exhaust Valve Opening). This can be done with appropriate calculations and one way of performing this calculation is explained below. Alternatively, other models with similar functions can be used.

wobei K_calibrate zum Kalibrieren des Modells verwendet wird. K_calibrate besteht aus einer Konstante, die üblicherweise im Bereich von 0 bis 1 liegt, aber auch angeordnet sein kann, andere Werte anzunehmen, und die einzeln Zylinder für Zylinder oder für einen bestimmten Motor oder Motortyp bestimmt wird, und hängt insbesondere von der Gestaltung der Einspritzdüsen (Zerstäuber) ab. dQ kann ebenfalls auf eine andere geeignete Weise, beispielsweise durch Einbeziehen anderer Parameter wie die Turbulenz bei der Kraftstoffzufuhr, modelliert werden, sofern ein Modellieren auf eine geeignete Weise möglich ist.The expected resulting exhaust gas temperature at the time of opening the exhaust valve after combustion of the combustion stroke may, in one embodiment, be as follows in step 307 to be appreciated. It is obvious that the temperature curve for the entire combustion and not just the final temperature can be estimated according to the presented method. It is clear to a person skilled in the art that the combustion can be modeled using the following equation (1): $$dQ=K_{calibrate}\left({\dot{Q}}_{fuel}-Q\right)$$

where K _{calibrate is used} to calibrate the model. K _calibrate consists of a constant, which is usually in the range from 0 to 1, but can also be arranged to assume other values, and which is determined individually cylinder by cylinder or for a specific engine or engine type, and depends in particular on the design of the Injection nozzles (atomizers). dQ can also be modeled in another suitable way, for example by including other parameters such as the turbulence in the fuel supply, if modeling is possible in a suitable way.

Q _fuel consists of the energy value of the injected fuel quantity, Q consists of the amount of energy burned. The combustion dQ thus corresponds to the amount of fuel injected minus the amount of fuel used up to that point. The combustion dQ can alternatively be modeled using another suitable model in which, for example, other parameters are also taken into account. For example, combustion may also be a function that depends on a model of turbulence on the air / fuel supply that may affect combustion to a different extent depending on the amount of air / fuel supplied.

For example, the fuel injections can be modeled as a sum of step functions: $$\text{u}={\displaystyle \underset{\text{k}=0}{\overset{\text{n}}{\Sigma }}\mathrm{\theta }\left(\text{t}-{\left({\text{t}}_{\text{inj},\text{begin}}\right)}_{\text{k}}\right)}-\mathrm{\theta }\left(\text{t}-{\left({\text{t}}_{\text{inj},\text{end}}\right)}_{\text{k}}\right)$$

The fuel flow measured as the supplied mass m during an injection k, i.e. how much fuel gets into the combustion chamber in the time window u when the injection is carried out, expressed as the duration of the crank angle degree Θ interval during which the injection nozzle is open, for a specific injection k can be modeled as follows: $$\frac{dm}{dt}=f\left(m\right)u$$

Where m represents the amount of fuel injected and f (m) depends, for example, on the injection pressure, etc. For example, f (m) can be measured or estimated in advance.

The energy value Q _LHV for the fuel such as diesel or gasoline is generally specified so that such a general specification can be used. The energy value can also be provided specifically by the fuel manufacturer, for example, or can be approximated for a country or region, for example. The energy value can also be arranged by estimating through the control of the vehicle. With the energy value, the equation (1) can be solved and the heat release can be determined with the progress of the combustion.

wobei Φ den Kurbelwinkelgrad darstellt, das heißt die Druckänderung ist in Kurbelwinkelgrad ausgedrückt, was zu einem Beseitigen der Abhängigkeit von der Motordrehzahl des Verbrennungsmotors während der Berechnungen führt. Y stellt einen Parameter dar, der vorab geschätzt, auf einen festen Wert festgelegt oder während der laufenden Verbrennung berechnet werden kann. Y ist allgemein das Wärmekapazitätsverhältnis, das heißt $\gamma =\frac{C_p}{C_v}=\frac{C_p}{C_p-R},$

wobei C_p und/oder C_v allgemein verfügbar und für verschiedene Moleküle tabellarisch erfasst sind; da die Verbrennungschemie bekannt ist, können diese tabellarischen Werte zusammen mit der Verbrennungschemie zum Berechnen der Auswirkung von jedem Molekül (beispielsweise Wasser, Stickstoff, Sauerstoff usw.) auf beispielsweise den gesamten Cp-Wert verwendet werden, so dass dieser für die zuvor genannten Berechnungen mit hoher Genauigkeit vorab oder während beispielsweise der laufenden Verbrennung bestimmt werden kann.Furthermore, by using a predictive heat release equation, the pressure change in the combustion chamber can be estimated as follows, for example: $$dp=\left(\frac{dQ}{d\phi }-\frac{\gamma }{\gamma -1}p\frac{dv}{d\phi }\right)\left(\frac{\gamma -1}{V}\right)d\phi$$

where Φ represents the crank angle degree, that is, the pressure change is expressed in crank angle degree, which leads to the elimination of the dependency on the engine speed of the internal combustion engine during the calculations. Y represents a parameter that can be estimated in advance, set to a fixed value, or calculated during ongoing combustion. Y is generally the heat capacity ratio, that is $\gamma =\frac{C_p}{C_v}=\frac{C_p}{C_p-R}.$

where C _p and / or C _{v are} generally available and tabulated for different molecules; Since the combustion chemistry is known, these tabular values can be used together with the combustion chemistry to calculate the effect of each molecule (e.g. water, nitrogen, oxygen, etc.) on the total Cp value, for example, so that it can be used for the above calculations high accuracy can be determined in advance or during, for example, ongoing combustion.

P_initial stellt einen Ausgangsdruck dar, der vor Beginn der Verdichtung beispielsweise den Umgebungsdruck für Verbrennungsmotoren ohne einen Turbolader oder einen herrschenden Verbrennungsluftdruck für einen Motor mit einem Turbolader darstellen kann. Wenn die Schätzung zu einem späteren Zeitpunkt während des Verbrennungstakts erfolgt, kann P_initial den dann herrschenden Druck wie vom Drucksensor 206 ermittelt darstellen. Somit kann der Druck im Brennraum für die gesamte Verbrennung geschätzt werden, wobei die Schätzung nach jeder Einspritzung oder die nächste Schätzung nach Verstreichen einer bestimmten Zeit zu einer zunehmend höheren Genauigkeit der Schätzung führt, da die tatsächliche Druckänderung während eines zunehmenden Teils des Verbrennungstakts bekannt ist.Alternatively, C _p and / or C _{v can} be approximated in a suitable manner. The integration of equation (4) gives the following result: $$p=p_{initiel}+{\displaystyle \int dp}=p_{initiel}+{\displaystyle \int \left(\frac{dQ}{d\phi }-\frac{\gamma }{\gamma -1}p\frac{dV}{d\phi }\right)\left(\frac{\gamma -1}{V}\right)d\phi }$$

P _initial represents an output pressure that can represent, for example, the ambient pressure for internal combustion engines without a turbocharger or a prevailing combustion air pressure for an engine with a turbocharger before compression begins. If the estimate is made at a later point in time during the combustion cycle, P can _{initially determine} the pressure then prevailing as from the pressure sensor 206 represent determined. Thus, the pressure in the combustion chamber can be estimated for the entire combustion, the estimate after each injection or the next estimate after a certain time has elapsed, which leads to an increasingly higher accuracy of the estimate, since the actual pressure change during an increasing part of the combustion cycle is known.

Using the pressure estimated with equation (5), a corresponding estimated average temperature test for the gas in the combustion chamber for, for example, EVO or for the entire combustion can then be calculated using the estimated pressure at EVO and the general gas law: $$r=\frac{pV}{nR}$$

The volume V, that is to say the volume of the combustion chamber, which changes continuously with the piston movement, can be recorded in a table in the control system of the vehicle or can be calculated in a suitable manner and is dependent on the crank angle due to the piston movement.

The amount of substance n, i.e. the amount of gas in the combustion chamber, changes with the progress of the combustion. The amount of substance changes due to the chemical reactions that occur during combustion. However, this change is normally only one or a few percent, so that, according to one embodiment, the amount of substance n can be used as the amount of substance before combustion.

If the change in the amount of substance is modeled during combustion, this can be modeled as follows, for example: $$n=\left(1-\frac{Q_{nOw}}{Q_{tOtal}}\right)n_{befOre\_cOmb}\left(\lambda .m_{fuel}\right)+\frac{Q_{nOw}}{Q_{tOtal}}{n}_{all\_cOmb}\left(\lambda .m_{fuel}\right)$$

The quantity of substance n changes over the course of the stroke time from a quantity of substance n _{before_comb} present before the combustion to a quantity of substance n _{all_comb} when all the injected fuel has been burned during the combustion cycle. λ represents the fuel / air ratio and Q _total denotes the total fuel energy that is made available to the combustion during the combustion cycle. m _fuel represents the amount of fuel supplied and Q _total the amount of energy that has been burned to date, the determination being based on equation (4) and / or using the signal from the pressure sensor and the diagnostic heat release according to equation (8): $$\frac{dQ}{d\theta }=\frac{\gamma }{\gamma -1}p\frac{dv}{d\phi }+\frac{1}{\gamma -1}V\frac{dp}{d\theta }$$

With the preceding equations, the entire temperature curve for the combustion from the first injection to EVO can thus be estimated by calculating with equation (6) for the entire combustion with a certain corresponding resolution such as crank angle degrees or tenths, hundredths or thousandths crank angle degrees, etc., that is the temperature change over the entire combustion process can be predicted. For example, this estimated temperature curve may look like the temperature curve T _Θ1est in 4 , where the expected temperature development and the target temperature T _targetEVO are also shown.

Obviously, however, the temperature curve can have essentially any appearance, depending on the amount of fuel injected and the time of the injection. Regarding the control of the exhaust gas temperature, the temperature at EVO after combustion (alternatively the entire temperature curve as explained before) is in step 306 estimated. The first injection thus causes combustion and thus heat release and an increase in pressure. If the combustion proceeds exactly as expected, this temperature corresponds to the originally expected temperature, that is T _evo1evo would out T _targetEVO persist, but once the pressure at Θ ₁ , and with it the temperature T _Θ1 (please refer 4 ), deviates from the estimated pressure, the estimated T _Θ1EVO as well as the entire new estimated temperature curve T _Θ1est from the expected / desired temperature T _targetEVO according to the selected injection sequence.

The actual temperature curve will therefore presumably deviate from the predicted temperature curve in the course of the combustion due to the heat losses, the deviations from the modeled combustion, etc.

For this reason, the control of the combustion is performed according to the invention, and according to the present invention, deviations from the predicted temperature curve are compensated for after the first injection insp _{1 is} completed. On the basis of the determined difference between how the combustion should have taken place and how it actually took place, a controller can be used which controls the subsequent combustion, for example on the basis of the difference, taking into account the extent and type of the difference can.

The one in step 306 determined pressure p _fΘ1 , which the temperature T _fΘ1 in 4 corresponds to step 306 used as P _initial as previously described to T _Θ1EVO with data obtained during combustion. In other words, the cylinder _temperature can be measured with the measured pressure p _fΘ1 T _Θ1EVO can be calculated according to equation (6).

So in step 307 a more likely final temperature using the equations listed above T _EVO to be appreciated. This estimated temperature is then in step 308 used to control subsequent fuel injection based on the estimated temperature (pressure).

With at least a second, but in the present example at least a total of three injections (during the combustion cycle), the combustion can move in the direction of a desired final temperature T _targetEVO can be controlled by controlling the following injections. When the first injection is completed, at least two additional injections remain in the present example, which are adjusted during the control action.

A first example of how the control action can be carried out is to distribute the duration and thus the amount of fuel injected between these injections and / or to change the injection times for one or more injections in succession. The control action is carried out during this control action, provided that the required work is still being carried out, that is to say the combustion cycle continues to generate a required torque on the output shaft of the internal combustion engine. The distribution between the second and third injection can be based on whether the estimated temperature value at EVO exceeds or falls below the reference value for the temperature.

This control action can be adapted in any way, but can be implemented, for example, in the form of a proportional regulator, which is used, for example, to determine the size of the quantity to be displaced between fuel injections, which is, for example, an increase / decrease Δu in the period during which the injection in the respective injection process takes place, can be expressed. During this control action, the total amount of fuel injected may also change, for example because the required work still needs to be done, but it is necessary to adjust the amount of fuel to compensate for changes in efficiency.

$$\Delta u_{durationinj\text{ 3}}=-\Delta u_{durationinj2}$$

wobei e die Abweichung vom Referenzwert darstellt. Ferner kann eine entsprechende Steuerungsaktion alternativ oder zusätzlich für die Einspritzzeit ausgeführt werden, wobei beispielsweise der Beginn der Einspritzung nach vorne verschoben oder verzögert werden kann. Statt der proportionalen Regelung kann eine herkömmliche PI- oder PID-Regelung verwendet werden. Das Verfahren kehrt anschließend zu Schritt 304 zurück, wobei die Einspritzung i gemäß der neuen Einspritzfolge ausgeführt wird. Wenn diese i=2 Einspritzung abgeschlossen ist, bestimmt wieder der Schritt 305, ob alle Einspritzungen abgeschlossen sind. Da dies noch nicht der Fall ist, wird i um Eins für die nächste Einspritzung inkrementiert, wobei der Druck im Brennraum erneut (jetzt als p_fΘ2 nach insp i=2) mit einem Drucksensor 206 bestimmt wird, so dass eine neue Schätzung von T_EVO nach einer Einspritzung insp₂ durchgeführt wird, um bei Bedarf insp₃ nach wie vor unter Berücksichtigung des Verrichtens der gewünschten Arbeit anzupassen. Die Schätzung wird wie zuvor beschrieben durchgeführt, mit dem Unterschied, dass sich der Ausgangswert P_initial aufgrund der Verbrennung durch die erste Einspritzung zu p_fΘ2 geändert hat. Wenn alle Einspritzungen abgeschlossen sind, kehrt das Verfahren von Schritt 305 zu Schritt 301 zur Steuerung eines folgenden Verbrennungstakts zurück.In step 308 A control action of the duration for the two successive injections insp ₂ and insp ₃ can thus in each case be carried out, in the present example a constant K which is determined in a suitable manner and with the difference e between the estimated target temperature (target pressure) and the desired target temperature (Target pressure) is used to determine a change in duration for the injection insp ₂ , in the present example a corresponding change is carried out for insp ₃ (see equations (8) and (9)). $$\Delta u_{duratiOninj2}=K\cdot e$$

$$\Delta u_{duratiOninj\text{3}}=-\Delta u_{duratiOninj2}$$

where e represents the deviation from the reference value. Furthermore, a corresponding control action can alternatively or additionally be carried out for the injection time, it being possible, for example, to shift the start of the injection forward or to delay it. Conventional PI or PID control can be used instead of proportional control. The process then returns to step 304 back, the injection i being carried out according to the new injection sequence. When this i = 2 injection is completed, the step determines again 305 whether all injections have been completed. Since this is not yet the case, i is incremented by one for the next injection, the pressure in the combustion chamber again (now as p _fΘ2 after insp i = 2) with a pressure sensor 206 is determined, so a new estimate of T _EVO after an injection insp _{2 is} carried out in order to adapt insp ₃ as required, taking into account the performance of the desired work. The estimation is carried out as described above, with the difference that the initial value P has _initially changed to p _fΘ2 due to the combustion by the first injection. When all injections are complete, the process returns from step 305 to step 301 to control a subsequent combustion stroke.

The control can also be done in such a way that the combustion is controlled in the direction of a desired temperature / desired temperature curve, but two or more combustion cycles are required before the desired result is achieved, but still with a control action as described above.

The control according to the invention can also include performing an estimate of a number of possible control alternatives, the control action then being carried out according to a corresponding measure of the several possible measures, for example on the basis of a cost function.

The present invention thus provides a method for controlling, based on a first parameter value determined after a first part of the combustion is complete, a subsequent part of the combustion during the same combustion stroke based on the first parameter value, wherein the Combustion is controlled with respect to a temperature for the combustion process as a desired final temperature as previously described.

Furthermore, in the determination in step 308 an expected temperature development for several different alternative injection sequences can be estimated for the remaining injections, so that the injection sequence that leads to the most advantageous temperature development can be selected when the next one Injection is running. Thus, in accordance with the present invention, combustion during ongoing combustion is adjusted based on deviations from the predicted combustion and, in one embodiment, each time an injection insp _{1 is} completed, as long as additional injections are to be performed.

According to the method described above, the injection sequence at the beginning of the combustion stroke was determined on the basis of tabular values; but according to one embodiment, the injection strategy can be determined before the start of the fuel injection in the manner described above, so that the first injection is thus carried out according to an injection sequence determined as described above, for example by performing calculations for a plurality of injection sequences and selecting one that seems most advantageous.

Furthermore, the control has so far been described in a manner in which the characteristics for a subsequent injection are determined on the basis of the prevailing conditions in the combustion chamber after the previous injection. However, the control can also be arranged for continuous execution, wherein the pressure determinations can also be carried out with the pressure sensor during the current injection, and the injection sequence can be calculated and continuously corrected until the next injection begins. Alternatively, the current injection can also be influenced by calculated changes in the injection sequence, even in the cases in which several shorter injections are carried out. The injection may also consist of a single longer injection, with changes to the current injection being able to take place continuously, for example by a so-called shape shaping, for example by changing the opening area of the injection nozzle and / or the pressure with which the fuel is injected on the basis of estimates and measured pressure values during injection. Furthermore, the fuel supply during the combustion can comprise only two fuel injections, with for example only the second or both injections being controlled, for example, with a course shaping. A course can also be formed if three or more injections are carried out.

Furthermore, the invention was previously explained with an example in which three injections are carried out during one combustion cycle. Of course, more injections can be performed during one combustion cycle. Since multiple fuel injections result in multiple lengths of time having to be changed over time, as well as maintaining the work done, the calculations can become more extensive. For example, a very large number of injections, such as 10 or even 100 injections, can be arranged to be carried out during the same combustion stroke.

In such situations, there can be several corresponding injection strategies, which thus lead essentially to the same result. This leads to an undesirable complexity in the calculations.

According to one embodiment, a controller is used which corresponds to the controller described above. This is achieved by treating the closest injection as a separate injection and subsequent fuel injections as a single additional "virtual" injection. This is in 5A explained, the injection 501 As previously explained, insp ₁ corresponds to injection 502 insp ₂ corresponds, as previously explained, and with the remaining injections 503 to 505 as a single virtual injection 506 treated, that is, the injection 506 is treated as an injection with an amount of fuel that is substantially the total amount of fuel for the injections 503 to 505 corresponds, with a distribution between the injection 502 and virtual injection 506 can be done. With such a procedure, the change between insp ₂ and subsequent injections does not have to be specific between the injections 503 to 505 be distributed, but the distribution takes place at this stage in each case between the injection 502 and the "virtual" injection 506 ,

Once the injection 502 is completed, the process is repeated exactly as described above with a new determination of an injection sequence in order to control the temperature, but with the injection 503 as a separate injection (see 5B) , and the injections 504 . 505 together represent a virtual injection with a distribution as previously described.

In 5A there is virtual injection 506 from three injections; but it is obvious that the virtual injection 506 can generally include more than three injections, about ten injections or hundreds of injections, depending on how many injections are to be made during the combustion stroke, so that the process is repeated until all injections are completed.

Furthermore, the fuel supply during the combustion may comprise only two fuel injections, the controlled injection being controlled, for example, with the course shaping. A course can also be formed if three or more injections are carried out. It may also be the case that a single injection is performed during a combustion stroke, with the parameters for this injection change during the ongoing injection by means of curve shaping on the basis of new estimates with continuous combustion, that is to say for example the injection pressure and / or the duration of the Injection, can be controlled during an ongoing injection.

So far, the control with the goal of reaching a desired exhaust gas temperature T _EVO described. This may be the case, for example, when it is desirable to achieve / maintain a certain temperature in one or more aftertreatment components. The temperature control of aftertreatment components per se is state of the art and is not the subject of the present invention; but the present invention provides a means of improving temperature control. For example, the control may relate to controlling exhaust gas temperature, for example to achieve a desired SCR temperature, DPF temperature, or DOC temperature. Temperature control can also be used, for example, to solve problems due to the rapid temperature rise in an SCR catalyst or DOC / DPF with the safety and system risks that a rapid temperature rise can cause. In such situations, the combustion can go towards a low T _EVO controlled with the aim of lowering the temperature in the aftertreatment system. The controller can also be provided for another type of controller, for example a DOC catalytic converter, a TWC catalytic converter or a particle filter system such as a PMFC or DPF system.

However, controlling the temperature of the combustion according to the invention can also be used to limit emissions, that is to say to control the composition which the resulting exhaust gas flow has.

As previously explained, in the case of exhaust gas temperature control, temperature estimation is most important in EVO; but in the case of a control with regard to the exhaust gas emissions, the entire temperature curve (temperature change curve) which the combustion completes is instead relevant, so that the control is carried out with the aim of possibly obtaining a desired temperature change curve during the combustion. In this case, computer-based models (“black box” models) can be used as a representation of emissions in relation to temperature, so that the temperature curve is controlled in such a way that the occurrence / presence of one or more substances during combustion is influenced , In these computer-based models, the expected emissions can also depend on “global” parameters such as EGR, lambda value, intake pressure, ambient temperature, etc. Alternatively, physical models can be used. In general, physical models may be preferred / available for certain substances, while computer-based models may be required for other substances due to the lack of suitable physical models. The combustion can be controlled, for example, in relation to a proportion and / or a concentration for one or more exhaust gas components such as KW, CO, NO _x , NO, NO ₂ and soot.

According to the invention, an MPC (Model Predictive Control) can also be used for control.

An example of an MPC is in 6 shown, with the reference curve 603 corresponds to the expected temperature development during a combustion cycle. The curve 603 thus represents the temperature development that is aimed for during the combustion cycle, the combustion only in the direction of a final value or continuously in the direction of the curve 603 can be controlled.

The solid curve 602 up to the point in time k represents the actual development of the temperature up to the point in time k which, as described above, was calculated with actual data from the pressure sensor resolved by the crank angle. The curve 601 represents the expected temperature development on the basis of the selected injection profile and thus forms the temperature development that is expected. The dashed injections 605 . 606 . 607 represent the predicted control signal, that is, the injection profile likely to be applied, and 608 . 609 represent already completed injections.

The predicted injection profile is updated at appropriate intervals, for example after each completed injection, to achieve the desired final value, that of the reference curve 603 is specified, the next injection being determined on the basis of the prevailing conditions in relation to the estimated heat loss development.

Thus, the present invention provides a method that enables very good control of a combustion process and that adjusts the combustion during the ongoing combustion to achieve a combustion that more closely matches the desired combustion to a desired exhaust gas temperature and / or or to achieve a desired emission limit.

Furthermore, as previously described, the combustion gas temperature is estimated for several different alternative injection sequences for the remaining injections, so that the injection sequence leading to the most advantageous temperature can be selected when the next injection is carried out. If multiple injection sequence / control alternatives meet the appropriate conditions, other parameters can be used to choose which of them to use. There may also be other reasons for performing control simultaneously based on other parameters. For example, injection sequences can also be selected in part based on pressure amplitude, heat loss, rate of pressure change, work done in the combustion chamber and / or nitrogen oxides generated during combustion, in addition to being able to be selected based on temperature, the determination according to one of the parallel patent applications listed below can be carried out.

Especially in the parallel registration DE 11 2014 001 770 T5 “Method and system for controlling an internal combustion engine V” describes a method for controlling the following combustion on the basis of an estimated maximum pressure amplitude.

Additionally describes the parallel registration DE 11 2014 001 782 T5 "Method and system for controlling an internal combustion engine I" (Swedish patent application, application number: 1350506-0) a method for controlling the following combustion based on an estimated maximum pressure change rate.

The parallel registration also describes DE 11 2014 001 773 T5 “Method and system for controlling an internal combustion engine III” means a method during a first combustion cycle for controlling combustion during a subsequent part of the first combustion cycle in relation to the work performed during the combustion.

The parallel registration also describes DE 11 2014 001 774 T5 "Method and system for controlling an internal combustion engine IV" means a method during a first combustion cycle for controlling combustion during a subsequent part of the first combustion cycle, with respect to an illustration of a heat loss during combustion.

The parallel registration also describes DE 11 2014 001 776 T5 “Method and system for controlling an internal combustion engine VI” means a method during a first combustion cycle for estimating a first measure of nitrogen oxides resulting from the combustion during the first combustion cycle and for controlling the combustion during a subsequent part of the first combustion cycle based on the first measure.

The invention was previously explained in a manner in which a pressure sensor 206 is used to determine the pressure in the combustion chamber and the pressure can then be used to estimate a temperature. As an alternative to using pressure sensors, one (or more) other sensors can be used, for example high-resolution ion current sensors, knock sensors or strain gauges, wherein the pressure in the combustion chamber can be modeled with sensor signals from such sensors. Different types of sensors can also be combined, for example in order to achieve a more reliable estimate of the pressure in the combustion chamber, and / or other corresponding sensors can be used, the sensor signals being converted into corresponding pressures for temperature control as described above.

Furthermore, only the fuel injection was adjusted in the previous description. Instead of controlling the amount of fuel supplied, the combustion chamber temperature can be arranged to be controlled, for example, with exhaust gas valves, so that the injection can be carried out according to a predetermined sequence, but the exhaust gas valves are used to control the pressure in the combustion chamber and thus also the temperature.

Furthermore, the control can be carried out with a suitable type of controller or, for example, with state models and a state feedback (for example linear programming, LQR method or the like). The method according to the invention for controlling the internal combustion engine can also be combined with sensor signals from other sensor systems in which the resolution according to the crank angle value is not available, for example pressure sensors, NO _x sensors, NH ₃ sensors, soot sensors, oxygen sensors and / or temperature sensors, etc ., and their input signals can be used, for example, as input parameters in the estimation of, for example, the expected pressure / temperature with computer-based models.

In addition, the present invention was previously explained with respect to vehicles. However, the invention is applicable to any means of transportation / processes to which the temperature control as described above can be applied, such as, for example, watercraft or aircraft with combustion processes as described above.

It should also be noted that the system can be modified according to various embodiments of the method according to the invention (and vice versa).

Claims (37)

Method for controlling an internal combustion engine (101), the internal combustion engine (101) comprising at least one combustion chamber (201) and elements (202) for supplying fuel to the combustion chamber (201), the combustion in the combustion chamber (201) taking place in combustion cycles, the method being characterized in that: during a first part of a first combustion cycle with a first sensor element (206) a first parameter value is determined which represents a physical quantity for the combustion in the combustion chamber (201), - on the basis of the first Parameter value, the combustion is controlled during a subsequent part of the first combustion stroke, so that in the control the combustion is controlled during the following part of the first combustion stroke with respect to a resulting temperature in the subsequent combustion, - based on the first parameter value, estimating one Representation of a temperature resulting from combustion (T _targetEVO ) and / or temperature change during the following part of the first combustion _stroke after the first part of the first combustion _stroke , and - based on the estimated resulting temperature (T _targetEVO ) and / or temperature change, controlling the combustion during the following part of the first combustion _stroke . Procedure according to Claim 1 , also comprising: determining the first parameter value when a part of the first combustion stroke has elapsed. Method according to one of the preceding claims, also comprising: determining the first parameter value when the combustion of fuel has started during the first combustion stroke. Method according to one of the preceding claims, also comprising: - determining a parameter value corresponding to the first parameter value at a number of times / crank angle positions during the first combustion cycle and for the respective determined parameter value the estimation of a respective resulting temperature and / or temperature change during the first combustion cycle, and controlling combustion during a subsequent part of the first combustion cycle after determining the respective parameter value based on a respective estimated temperature and / or temperature change during the first combustion cycle. Method according to one of claims 1 to 4, wherein the combustion is controlled during the following part of the first combustion _stroke with respect to a resulting temperature (T _targetEVO ) for the combustion _stroke . A method according to any one of claims 1 to 5, wherein the combustion is controlled during the following part of the first combustion stroke with respect to a temperature change during the following part of the first combustion stroke. Method according to one of the preceding claims, also comprising estimating an expected value for the physical quantity, wherein the combustion during the following part of the first Combustion stroke is controlled based on a comparison between the estimated value and the determined value for the physical quantity. Method according to one of the preceding claims, wherein the temperature for the combustion is a representation of an average temperature for the combustion chamber (201). Method according to one of the preceding claims, also comprising estimating a representation of a resulting temperature and / or temperature change for the following part of the first combustion stroke on the basis of the first parameter value, so that the subsequent combustion on the basis of the representation of the resulting temperature and / or Temperature change for the following part of the first combustion stroke is controlled. Procedure according to Claim 9 , wherein the representation of a temperature and / or temperature change is estimated by an estimate of a pressure change in the combustion chamber (201) during the following part of the first combustion stroke. Procedure according to Claim 10 , the pressure change in the combustion chamber (201) being estimated with an estimate of a heat release during the combustion. Procedure according to Claim 11 further comprising estimating the heat release based on the amount of fuel to be supplied for combustion. Method according to one of claims 1, 8 to 12, wherein the representation of a temperature and / or temperature change during the control is represented by a corresponding pressure and / or a corresponding pressure change in the combustion chamber (201). Method according to one of the preceding claims, wherein during the control of the combustion in the direction of a temperature and / or temperature change, the control is carried out in the direction of a pressure corresponding to the temperature in the combustion chamber (201). Method according to one of the preceding claims, wherein the sensor element consists of at least one pressure sensor element (206) and wherein the first parameter value represents a pressure prevailing in the combustion chamber (201) during the first combustion cycle. Method according to one of the preceding claims, also comprising controlling the combustion during the following part of the first combustion stroke by controlling the amount of fuel for supply to the combustion chamber (201). Procedure according to Claim 16 The fuel supply to the combustion chamber is controlled by controlling the fuel injection with at least one fuel injection nozzle (202). Procedure according to Claim 16 or 17 wherein at least one fuel injection is performed during the following portion of the combustion stroke, controlling the amount of fuel for the injection and / or the injection duration and / or the injection pressure and / or the time between injections for the at least one fuel injection. A method according to any one of claims 16 to 18, wherein at least two fuel injections are performed during the following part of the combustion stroke, the combustion also being controlled after the first of the at least two fuel injections. A method according to any one of claims 16 to 19, wherein during control of combustion, at least three fuel injections are performed during the following part of the combustion process, while during control of a first of at least three fuel injections, the remaining fuel injections are treated as a single total injection. A method according to any one of claims 16 to 20, wherein the control of the combustion during the following part of the first combustion stroke is carried out at least in part by controlling the fuel injected into the combustion chamber (201) during an ongoing fuel injection. 22. The method of any one of claims 16 to 21, further comprising changing a distribution of fuel quantities between at least two fuel injections during control of the fuel injected into the combustion chamber (201). The method of any one of claims 16 to 22, further comprising applying a predetermined injection of fuel at the start of the combustion stroke, wherein the control occurs after a first injection has at least started but before the fuel injection is completed during the first combustion stroke. The method of any preceding claim, further comprising performing a first fuel injection into the combustion chamber (201) during the first part of the first combustion stroke and at least a second fuel injection during the following part of the combustion stroke, the control of the second fuel injection being determined after the first fuel injection is at least partially completed. Method according to one of the preceding claims, further comprising determining a representation of an expected temperature and / or temperature change for the following part of the combustion cycle for at least a first and a second control alternative during the control of the combustion during the following part of the combustion, and - Selecting a control alternative from a plurality of control alternatives for controlling the following part of the combustion cycle. Procedure according to Claim 25 wherein the control alternative includes alternatives for the injection of fuel during the following part of the combustion stroke. Method according to one of the preceding claims, also comprising controlling the combustion during the following part of the first combustion stroke by controlling one or more valves which are actuated on the combustion chamber (201). Method according to one of the preceding claims, wherein the control of the temperature in relation to a proportion and / or a concentration takes place for one or more exhaust gas components in the group comprising: hydrocarbon (KW), carbon monoxide (CO), nitrogen oxides (NO _x ), nitrogen monoxide (NO), nitrogen dioxide (NO ₂ ), soot. Method according to one of the preceding claims, wherein during the control, the combustion during the following part of the first combustion cycle is controlled with respect to a desired temperature or a desired temperature change, the control being carried out in the direction of the desired temperature and / or temperature change during a plurality of combustion cycles. Method according to one of the preceding claims, wherein the exhaust gas stream resulting from the combustion in the internal combustion engine is post-treated in a post-treatment system which comprises one or more elements from the following group: - A catalyst for reducing hydrocarbons and / or carbon oxides and / or nitrogen oxides; or - a particle filter system. Method according to one of the preceding claims, wherein the first parameter value, which represents a physical variable for the combustion in the combustion chamber (201), is determined at least at every crank angle degree, every tenth of every crank angle degree or every hundredth of every crank angle degree. Method according to one of the preceding claims, wherein the first parameter value is determined by using one or more elements from the following group: cylinder pressure sensor, knock sensor, strain gauge, tachometer, ion current sensor. Computer program comprising a program code which, when the program code is executed on a computer, causes the computer to carry out the method according to one of claims 1 to 32. Computer program product comprising a computer readable medium and a computer program according to Claim 33 , the computer program being contained in the computer-readable medium. System for controlling an internal combustion engine (101), the internal combustion engine (101) comprising at least one combustion chamber (201) and elements (202) for supplying fuel to the combustion chamber (201), the combustion in the combustion chamber (201) taking place in combustion cycles, the method being characterized in that the system comprises: - elements (115) which, during a first part of a first combustion cycle, determine a first parameter value with a first sensor element (206), which parameter determines a physical quantity for the combustion in the combustion chamber (201 ) - elements (115) which, based on the first parameter value, control the combustion during a subsequent part of the first combustion stroke, so that during the control the combustion during the following part of the first combustion stroke with respect to a resulting temperature at the following Combustion is controlled - elements (115) based on the first parameter value a Da establishing a temperature resulting from a combustion (T _targetEVO ) and / or temperature change during the following part of the first combustion _stroke after the first part of the first combustion stroke, and - elements (115) based on the estimated resulting temperature (T _{tar getEVO} ) and / or temperature change control combustion during the following part of the first combustion stroke. System according to Claim 35 , characterized in that the internal combustion engine is an element from the group consisting of a vehicle engine, a boat engine and an industrial engine. Vehicle (100), characterized in that there is a system according to Claim 35 or 36 includes.

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