SE0950057A1 - Exhaust purification system and filter regeneration method - Google Patents

Abstract

The invention relates to an exhaust gas purification system (I; II) with active filter regeneration for an internal combustion engine. Arranged in an exhaust line (240) is a first catalyst (250) adjacent to the engine (230), a second catalyst (252) downstream of the first catalyst (250), a filter device (260) downstream of the second catalyst (252), and an injector device (270a; 270b) arranged to inject a fuel into the exhaust line (240) upstream of the first catalyst during a regeneration cycle. In addition, a second injector device (272) is provided to inject a fuel into the exhaust line (240) between the first catalyst. (250) and the second catalyst (252). The invention also relates to a method for filter regeneration, a motor-driven unit, a computer program for filter regeneration, as well as a computer program and a computer program product. (Fig. 2a)

Description

from the cylinders in the engine by controlling the fuel injection so that a certain part connection to the exhaust line, or the injector devices of fuel is not burned but injected as a so-called late post-injection, ie. fuel injection into cylinders aimed at fuel-enriching the exhaust gases, leaving the cylinders substantially unburned.

The advantage of using an external injector device is that it gives full freedom to choose when and where dosing of hydrocarbon should take place, as well as freedom to, regardless of engine considerations, choose how large the dosing should be. An external injector device can, however, cause problems with the distribution of the fuel in the exhaust gases, and also forms an additional part of the system.

The advantage of using the injector devices of the engine, in cases where the design of the injectors allows multiple injections with late post-injection, is that no additional part is required. However, problems can arise with e.g. cylinder polishing and oil dilution.

Catalyst / s and filters are normally placed as close to the engine as the installation allows. With regard to e.g. available volume and location of any diesel injector, however, this is usually a bit downstream in the exhaust system.

The temperature losses of the exhaust gas which is led to the catalyst can be limited by isolating the exhaust system or by moving only the catalyst, which causes the exhaust system when the exhaust gases are hotter during fuel injection. One closer to the engine, but increased temperature losses in alternative to limiting the heat losses in the exhaust system is to increase the exhaust temperature taken out of the engine, which leads to reduced efficiency of the engine. A further alternative is to use an additional catalyst in the form of a motor-driven catalyst, so-called Close Coupled Catalyst (CCC) and to leave the original catalyst arranged at a distance from the motor according to a conventional location.

A motor catalyst, CCC, is usually smaller than the remote catalyst because it causes less thermal inertia and thus results in rapid heating thereof. The rapid heating is desirable because CCC then more quickly reaches a temperature when fuel can be oxidized to heat the exhaust stream, catalyst and filter downstream. When the downstream catalyst has reached its temperature for fuel oxidation, it can cooperate with the CCC in heating the filter. If only the temperature of the catalyst can be maintained so that the catalyst is active, it is, from a temperature loss perspective, advantageous that the fuel is converted to heat as close to the filter as possible.

A problem with a catalyst located very close to the engine is that it is difficult to inject hydrocarbons from an external injector device far enough upstream of the engine near the engine to allow exhaust gases to mix with fuel. How much hydrocarbon will react depends on the temperature, exhaust gas flow and dimensioning of the catalysts. Thus, the proportion of hydrocarbon to be converted in the near-engine catalyst and the proportion of hydrocarbon to be converted in the remote catalyst can not be controlled because it depends on the temperature and dimension of the near-engine exhaust gas flow catalyst. Since the exhaust temperature increase in the respective catalyst is due to the fuel conversion, this cannot be regulated either, nor can the increased temperature losses which are connected to a temperature increase higher upstream in the exhaust system.

OBJECT OF THE INVENTION An object of the present invention is to provide an exhaust gas purification system which, with active filter regeneration, enables minimization of heat losses and a short response time.

A further object of the present invention is to provide a method and a computer program for active filter regeneration in an exhaust gas purification system of an internal combustion engine which enables minimization of heat losses and a short response time.

SUMMARY OF THE INVENTION These and other objects, which appear from the following description, by means of an aftertreatment of particles, a motor-driven unit, a computer program and exhaust gas purification system, a process for computer program product as above and further exhibiting the features set forth in the appended Claims 1, 6, 7, 10, 11 and 12. Preferred embodiments of the system and method are defined in the appended dependent claims 2-5 and 8-9.

According to the invention, a second injector device is arranged to inject a fuel into the exhaust line between the first catalyst and the second catalyst. By using the second injector device together with the injector device arranged to inject the hydrocarbon-based medium upstream of the first catalyst, rapid start-up and regeneration with cool exhaust gases with reduced heat losses is enabled. This enables control of the amount of fuel for the first catalyst and the amount of fuel for the second catalyst, whereby the temperature can be optimized for the regeneration so that the heat losses in the exhaust line are minimized.

This requires a smaller amount of fuel for the first catalyst, i.e. only the amount required to effect exothermic oxidation over the second catalyst. An efficient system is consequently obtained. Through this solution, an engine cylinder injector device can advantageously be used, whereby the risk of the walls of cylinders of the engine being hit because a smaller amount of fuel, in the case engine fuel, can be used for injection with the engine cylinder injector device, thereby avoiding deterioration of engine lubrication. shortened despite the use of engine cylinder injector device, and / or oil change can, despite the use of engine cylinder injector device, take place at larger intervals, since the amount of fuel, here engine fuel, injected into the cylinders here can be reduced.

According to an embodiment of the exhaust gas purification system, said first injector device consists of the engine's cylinder cylinder injector device, arranged to inject said fuel after ordinary, for combustion in cylinder of the engine, intended. In this way, the location of the first catalyst can be optimized without having to take into account an external injector device. This also means that no additional injector device is required upstream of the first catalyst.

According to an embodiment of the exhaust gas purification system, said first injector device consists of an external injector device. The advantage that the first injector device is also external is that it can then be placed arbitrarily.

According to an embodiment, the exhaust gas purification system further comprises a control unit arranged to control the injection from said first injector device on the first according to the dimensioning of and the second catalyst, the exhaust gas temperature before and / or the catalysts and / or the filter device. This streamlines the system and heat losses can be minimized.

According to an embodiment, the exhaust gas purification system further comprises a control unit arranged to control the injection from said second injector device on the basis of dimensioning of the first and second catalyst, the exhaust gas temperature before and / or after the catalysts and / or filter device and the injection from the first injector device.

This streamlines the system and heat losses can be minimized.

According to the inventive method according to claim 7, rapid start-up and regeneration with cool exhaust gases with reduced heat losses is enabled. This enables control of the amount of fuel for the first catalytic exothermic oxidation and the amount of fuel for the second catalytic exothermic oxidation, whereby the temperature can be optimized for the regeneration so that the heat losses in the exhaust line are minimized.

This requires a smaller amount of fuel for the first catalytic exothermic oxidation, i.e. only the amount required to enable exothermic oxidation at the second catalytic exothermic oxidation.

An efficient procedure is consequently obtained. Through this solution, an engine cylinder injector device can advantageously be used, whereby the risk of the walls of cylinders of the engine being hit by fuel is reduced because a smaller amount of fuel, in the case of engine fuel, can be used for injection with the engine cylinder injector device, thereby avoiding deterioration of engine lubrication. of the engine is not shortened despite the use of the engine cylinder injector device, and / or oil change can, despite the use of the engine cylinder injector device, take place at larger intervals, since the amount of fuel, here engine fuel, injected into the cylinders here can be reduced.

According to an embodiment of the method, the step of injecting fuel into the exhaust gas is effected so that the exhaust gas in the exhaust flow is fuel-enriched by means of the engine's cylinder cylinder injector device.Thereby the position of the first catalytic exothermic oxidation can be optimized. This also means that no extra exothermic oxidation.

According to one embodiment of the method, the amount of fuel is provided at the step of injecting fuel into the exhaust gas so that the exhaust gas in the exhaust gas flow is fuel enriched on the basis of the flow and temperature of the exhaust gas. This streamlines the process and heat losses can be minimized.

DESCRIPTION OF THE DRAWINGS The present invention is exemplified below with reference to the accompanying drawings, in which like reference numerals refer to like parts throughout the several Figures, and in which: Fig. 1 schematically illustrates a motor-driven unit, exemplified by a motor vehicle, according to an embodiment of the invention; Fig. 2a schematically illustrates an exhaust gas purification system according to a first embodiment of the invention; Fig. 2b schematically illustrates an exhaust gas purification system according to a second embodiment of the invention; Fig. 3 schematically illustrates a flow chart, according to an embodiment of the invention; Fig. 4 schematically illustrates a computer, according to an embodiment of the invention.

DESCRIPTION OF EMBODIMENTS In this specification, the term "link" refers to a communication link which may be a physical line, such as an optoelectronic communication line, or a non-physical line, such as a wireless connection, for example a radio or microwave link.

By fuel in the description is meant any suitable fuel which generates an exothermic reaction, for example oxidation, over a catalyst, where the fuel can be any hydrocarbon-based medium, i.e. substances containing carbon, hydrogen and / or additional substance / substances such as oxygen and nitrogen. Examples of such fuels are diesel, petrol, ethanol, natural gas and biogas. The fuel can also consist of hydrogen gas.

By catalyst in the description is meant a catalyst capable of exothermically oxidizing a fuel.

Fig. 1 embodiment is a vehicle driven by an internal combustion engine as schematically illustrates a motor-driven unit, which according to an example a motor vehicle 100, as shown in Fig. 1, or a motor boat.

According to a variant, the motor vehicle is a heavy vehicle, such as a truck or a bus, but can alternatively be a passenger car. According to another embodiment, the motor-driven unit is an internal combustion engine-driven apparatus such as a power plant. The exemplary vehicle 100 consists of a tractor 110 and a trailer 112.

Fig. 2a and Fig. 2b schematically illustrate an exhaust gas purification system I connected to an engine 230 of, for example, the motor vehicle 100 or another motor-driven unit; 11 according to a first embodiment and a second embodiment of the invention, respectively.

Exhaust gas purification systems I; ll are intended for after-treatment of particles from exhaust gases produced in the case of non-combustion of a fuel in the engine 230 where the after-treatment takes place by active regeneration.

The engine consists of an internal combustion engine 230, which according to one embodiment is a compression-ignition engine such as a diesel engine. According to another embodiment, the engine is an engine where the ignition takes place by generating an electric spark, such as an otto engine. The engine can thus be a petrol engine and according to yet another embodiment the engine is an ethanol engine. According to another variant, the engine is a so-called flexifuelmotor, i.e. can be operated with both ethanol and petrol in the desired mixture. According to a variant, the engine is a GDI engine (Gasoline Direct Injection), ie. an otto engine that injects the fuel, usually gasoline or ethanol, directly into the engine cylinders.

According to another variant, the engine is a gas engine such as a natural gas engine or biogas engine. According to another variant, the engine is one with so-called FAME fuel, ie. diesel fuel produced from esterified vegetable oils, driven engine.

The engine can be any engine where lean exhaust gases are produced during combustion or by adding oxygen-containing medium to the exhaust gases, ie. where there is oxygen left in the exhaust gas and where oxidizable particles, for example soot particles, are present in the exhaust gas.

Exhaust gas purification system I; 11 comprises an exhaust line 240 for conducting exhaust gases from the engine 230. The exhaust purification system further comprises a first catalyst 250 arranged in the exhaust line 240 adjacent to the engine 230 and a second catalyst 252 arranged in the exhaust line 240 downstream of the first catalyst 250. The exhaust purification system I; 11 also includes a filter device 260 disposed in the exhaust line 240 downstream of the second catalyst 252.

The exhaust line 240 may include one or more lines, and / or branches after engine 230 or after the first catalyst 250 or first before the filter device 260.

Exhaust gas purification system I; 11 also includes a first injector device 270a; 270b arranged to inject during a regeneration cycle a fuel into the exhaust line 240 upstream of the first catalyst 250 for heating the first catalyst 250 and the exhaust stream flowing through the catalyst 250, and a second injector device 272 arranged to inject a fuel into the exhaust line 240 between the first catalyst 250 and the second catalyst 252, i.e. downstream of the first catalyst 250 and upstream of the second catalyst 252.

By having a first injector device 270a; 270b arranged upstream of the first catalyst 250 and a second injector device 272 arranged upstream of the second catalyst 252 enable control of the degree of heating in the first catalyst 250 and the degree of heating in the second catalyst 252, whereby temperature loss in the exhaust line can be minimized while maintaining the possibility of rapid heating and regeneration and regeneration with, from the engine cool exhaust gases.

IO The first catalyst 250 is, according to a variant, a motor-driven catalyst 250, i.e. a so-called Close Coupled Catalyst, CCC, for the oxidation of hydrocarbons. 252 is hydrocarbon oxidation catalyst 252, where the second catalyst 252 then the fuel The second catalyst according to a variant one is diesel according to a variant constitutes a diesel oxidation catalyst 252, DOC (Diesel Oxidation Catalyst).

The motor catalyst 250 is smaller in dimension than the second catalyst 252 arranged at a distance downstream of the motor catalyst 250 because it causes less thermal inertia and thus causes rapid heating thereof, and the motor catalyst 250 does not have to take care of the same amount of hydrocarbon. .

The first catalyst 250 and / or the second catalyst may in one embodiment be divided into two or more subcatalysts or clusters of catalysts. Dividing the first and / or second catalyst into several catalysts can be advantageous for, among other things, space reasons, heating reasons, mixing reasons and / or production reasons.

The second injector device 272 is an external injector device 272.

The second injector device 272 is connected to the fuel tank 280 of the vehicle, the fuel tank 280 being the source of the fuel injected by the second injector device 272. Alternatively, the second injector device 272 could be connected to a separate source of fuel for injection by the same, wherein which preferably fuel which generates an exothermic reaction over the second catalyst, where the fuel may be of the same type as that of the vehicle fuel tank 280 or other type of fuel other than that contained in the fuel tank 280 and consequently used in the late post-injection by the first injector device 270a .

The filter device is any particle filter device that can filter particles present in the exhaust gases such as soot particles. When the fuel is diesel, 11 according to a variant filter device is a filter for purifying exhaust gases from a diesel engine, DPF (Diesel Particulate Filter).

When operating the engine 230 during an active regeneration cycle, the first injector device is 270a; 270b arranged to inject a fuel into the exhaust gas in the exhaust line 240 upstream of the first catalyst 250 so that the exhaust gas in the exhaust flow is fuel enriched. The amount of fuel injected by the first injector device 270a; 270b is adapted to generate the desired exothermic reaction in the engine-near catalyst 250, taking the exhaust gas flow rate into account when dimensioning the first 250. The catalytic converter 250 is then arranged to completely or partially heat and enrich the nitrogen-enriched exhaust gas in the exhaust stream in the exhaust line 240 by catalytic exothermic oxidation. By "partially heating the fuel-enriched exhaust gas" is meant to heat the exhaust gas. when it reaches the second catalyst 252 maintains the required temperature to heat or during regeneration keep the temperature of the second catalyst 252 at such a level that it is able to in turn exothermically oxidize the amount of fuel required to achieve the desired temperature of the exhaust gas flow into in the filter device 260.

The second injector device 272, which is external, is arranged to inject fuel into the, if required first catalyst 250, fully or partially heated exhaust gas in the exhaust flow in the exhaust line upstream of the second catalyst 252. The second injector device 272 is arranged to dispense the fuel which generates heat in the second catalyst 252.

The second catalyst 252 is arranged to heat, by catalytic exothermic oxidation, the heated and fuel-enriched exhaust gas in the exhaust gas stream, if required by the first catalyst 250, so that a heated exhaust gas in the exhaust gas stream is produced. The heated exhaust gas is arranged to be passed through the filter device 260, whereby a particle oxidation of particles such as soot particles of the filter device 260 takes place so that a particle-purified filter device 260 is obtained.

Exhaust gas purification system I; 11 comprises an electronic control unit 200 for controlling the system I; ll. The first injector device 270a; 270b is connected to the electronic control unit 200 via a link 202a; 202b. The external injector device 272 is connected to the electronic control unit via a link 204. The electronic control unit is arranged to control the first injector device 270a; 270b so as to dose the amount of hydrocarbon required to generate the desired exhaust gas temperature increase in the first catalyst 250, the control being based on the dimensioning of the first catalyst 250, the exhaust gas flow and the exhaust gas temperature in and out of the first catalyst. This gives the advantage that the exhaust gas flow is heated less in the first catalyst 250, which reduces the heat losses. This means that less fuel is required to raise the temperature and that the catalysts can be dimensioned for a longer fuel conversion and that they can thus become cheaper.

The electronic controller 200 is arranged to control the second injector device 272 so that the amount of hydrocarbon required to generate the desired exhaust temperature rise in the second catalyst 252 is metered.

A second control unit 210 is arranged for communication with the control unit 200 via a link 215. The second control unit 210 may be detachably connected to the control unit 200. The second control unit 210 may be a control unit external to the vehicle 100. The second control unit 210 may be arranged to perform the innovative steps according to the invention. The second control unit 210 can be used to load software to the control unit 200, in particular software for controlling the first injector device 270a; 270b and second injector device 272 for post-treatment of particulate matter from exhaust gas produced in the combustion of a fuel in an internal combustion engine 230 by active regeneration. The second control unit 210 may alternatively be arranged for communication with the control unit 200 via an internal network in the vehicle. According to a variant, the second control unit 210 constitutes a computer 210.

According to these embodiments, the control unit 200 is arranged to control the motor 230 via a link 233. For this purpose, the control unit 200 is signal-connected to operating means, such as e.g. injection valves of the first injector device 270a for injecting fuel into the cylinders of the engine 230.

Of course, separate control units for the motor 230 and the first injector device 270a, respectively; 270b and the second injector device 272 are provided. However, in that case these should be interconnected in order to be able to communicate relevant information between them.

The first embodiment according to Fig. 2a and the second embodiment according to Fig. 2b differ by the first injector device 270a; 270b.

According to the first embodiment of the exhaust gas purification system I illustrated in Fig. 2a, the first injector device 270a of the cylinders in the engine 230 comprises injectors arranged, herein referred to as the engine cylinder injector device 270a. In this case, injection during active regeneration is arranged to take place later than ordinary injection / s with the aim of delivering fuel to the combustion in the cylinder, for example at a position before the exhaust valves open so that the fuel injected into the engine 230 in this so-called late post-injection does not burn , and consequently is used for fuel enrichment of the exhaust gas in the exhaust line 240 upstream of the first catalyst 250.

The engine cylinder injector device is arranged to be able to perform at least one extra injection after the injection (s) burned in the cylinder have been completed.

By using the engine cylinder injector device 270a, the engine catalyst 250 can be located without having to consider the location of the injector device upstream thereof. By using the external second injector device 272 together with the engine cylinder injector device 270a, low dosing of fuel / hydrocarbon from the engine cylinder injector device 270a is enabled, so that problems with engine wear and oil dilution are reduced and can be substantially avoided.

The engine cylinder injector device 270a is connected to the electronic control unit 200 via a link 202a. The electronic control unit 200 is arranged to control the engine cylinder injector device 270a so that the amount of fuel exhaust temperature rise in the first catalyst 250, the control being metered as required to generate the desired dimensioning of the first and second catalysts 250, 252, and the exhaust temperature and exhaust flow before and / or after the catalysts and / or the filter device.

The fuel injected by the engine cylinder injector device 270a is according to a variant of the same kind as that injected by the external second injector device 272. According to another variant, the fuel injected by the engine cylinder injector device 270a differs from the fuel injected by the external second the injector device 272.

According to the second embodiment of the exhaust gas purification system II illustrated in Fig. 2b, the first injector device 270b is an external first injector device 270b arranged upstream of the first catalyst 250, which catalyst is constituted by a motor-driven catalyst 250. An advantage of using an external injector device 270b also as first injector device 270b is that problems with oil dilution and cylinder polishing are thereby completely avoided.

The external first injector device 270b is connected to the electronic control unit 200 via a link 202b. The electronic control unit 200 is arranged to control the external first injector device 270b so as to dose the amount of hydrocarbon required to generate the desired exothermic reaction in the engine near catalyst 250, the control being based on the dimensioning of the engine near catalyst 250 and the exhaust gas flow.

According to another variant, the fuel injected by means of the external first injector device 270b is of the same kind as that injected by means of the external second injector device 272. According to another variant, the fuel injected by means of the external first injector device 270b differs from the fuel. in by means of the external second being injected into the injector device 272.

The fuel used to drive the motor vehicle 100 or other motor-driven unit is, in a variant, the same as the fuel injected by means of the external first and / or the second injector device. According to another variant, the fuel used to propel the motor vehicle 100 or other motor-driven unit differs from the fuel by the external first and / or second injected into the injector device.

Fig. 3 schematically illustrates a flow chart of a process for post-treatment of particulates from exhaust gases produced by combustion of a fuel in an internal combustion engine, where the steps are performed in operation of the engine during an active filter regeneration cycle. has been heated to and maintained at a temperature enabling exothermic catalytic oxidation of injected fuel into the catalyst. This is accomplished by means of the combustion engine 230 taking exhaust temperature raising measures for the purpose of heating the exhaust gases out of the engine so as to heat or retain the heat of the first catalyst. By means of the electronic control unit 200, it is judged whether the first catalyst 250 is lit. If the exhaust gases from the engine after passage in the exhaust line 240 to the first catalyst 250 are hot enough for the first catalyst to be able to oxidize injected fuel, i.e. is lit, no temperature-raising measures are started before fuel is injected by means of the first injector device 270a, 270b. 250 the regeneration process would risk extinction, ie. not be able to oxidize If the first catalyst later under 16 fuel due to it being too cold, exhaust gas temperature raising measures are started when the need arises.

The method comprises a first step S310. In this step, a fuel is injected into the exhaust gas so that the exhaust gas flow is enriched with fuel. The fuel is injected by means of a first injector device 270a; 270b in the exhaust line 240 upstream of a first catalyst 250.

The method comprises a second step S320. In the step, by catalytic exothermic oxidation, the fuel-enriched exhaust gas is heated by means of the first catalyst 250, which according to a variant consists of a motor-like catalyst.

The method includes a third step S330. In this step, fuel is injected into the heated and fuel-enriched exhaust gas in the exhaust flow. The fuel is injected by a second external injector device 272 downstream of the first catalyst 250 and upstream of a second catalyst 252.

The method comprises a fourth step S340. In the step, by catalytic exothermic oxidation, the heated and fuel-enriched exhaust gas in the exhaust gas is heated so that a heated exhaust gas in the exhaust stream is produced by means of the second catalyst 252.

The method comprises a fifth step S350. In the step, the heated exhaust gas is passed through the filter device 260, whereby an oxidation of soot particles of the filter device 260 takes place so that a particle-purified filter device is obtained. The filter device 260 and particles present in the filter device are thereby heated to a temperature sufficient to effect oxidation of the particles in the filter device 260 and maintain the temperature, which temperature according to a variant is determined by means of the electronic control unit 200, which temperature can vary during this step. the step according to a variant is determined by means of the electronic control unit 200.

According to a variant, the method according to the invention comprises a step which is carried out before the fourth step. In this step, it is judged whether the second catalyst 17 is lit. According to a variant, this assessment is achieved by means of the electronic control unit 200.

After the fifth step S350, it is assessed whether the regeneration can be terminated.

This is accomplished according to a variant by means of the electronic control unit 200. first injector device 270a; 270b and the second injector device 272.

Thereafter, fuel injection is terminated by means of it. According to a variant, the order in which this is to take place is determined by means of the electronic control unit 200. Furthermore, according to a variant, the time between the first and last stopped injection is determined by means of the electronic control unit.

Thereafter, the exhaust gas temperature maintenance measures are terminated, which according to a variant is accomplished by means of the electronic control unit 200.

Fig. 4 schematically illustrates a computer, according to an embodiment of the present invention.

Referring to Figure 4, an embodiment of a device 200 is illustrated.

The control units described with reference to Figs. 2a and 2b may in one embodiment comprise the device 200. The device 200 comprises a non-volatile memory 420, a data processing unit 410 and a read / write memory 450.

The non-volatile memory 420 has a first memory portion 430 in which a computer program, such as an operating system, is stored to control the operation of the device 200. Further, the device 200 includes a bus controller, a serial communication port, I / O means, an A / D converter, a time and date input and transfer unit, an event counter and an interrupt controller (not shown). The non-volatile memory 420 also has a second memory portion 440.

A computer program P comprising routines for post-treatment of particles from exhaust gases produced during the combustion of a fuel in an internal combustion engine by active regeneration is provided. The program P may be stored in an executable manner or in a compressed manner in a memory 460 and / or in the read / write memory 450. 18 When it is described that the data processing unit 410 performs a certain function, it should be understood that the data processing unit 410 performs a certain part of the program which is stored in the memory 460, or a certain part of the program which is stored in the read / write memory 450.

The data processing unit 410 can communicate with a data port 499 via a data bus 415. The non-volatile memory 420 is intended for communication with the data processing unit 410 via a data bus 412. The separate memory 460 is intended to communicate with the data processing unit 410 via a data bus 411. 450 is the data processing unit 410 via a data bus 414.

When the data is received on the data port 499, it is temporarily stored in the second memory portion 440. When the received input data is temporarily stored, the data processing unit 410 is arranged to perform code execution on According to an information signal received on the data port 490 information generated by a as described above. execution includes e.g. an exhaust flow regulator, information concerning the engine operating point, operating point change, the engine exhaust flow and temperature out of the engine, temperatures in the exhaust flow and / or in the catalysts and / or in the filter device. This information can be used by the exhaust gas aftertreatment device 200 produced in the combustion of a fuel in an internal combustion engine by active regeneration.

Parts of the methods described herein may be performed by the device 200 by means of the data processing unit 410 running the program stored in the memory 460 or the read / write memory 450. When the device 200 runs the program, the methods described herein are executed.

According to one embodiment, the invention relates to a computer program P for active filter regeneration in the exhaust gas purification system of an internal combustion engine 230, said computer program comprising program code stored on a computer readable medium for performing steps S310; S320; S330; S340; S350, when said computer program is running on the electronic control unit 200 or the second control unit 210 / the computer 210 connected to the electronic control unit.

According to one embodiment, the invention relates to a computer program product comprising a program code stored on a medium readable by a computer for performing the steps S310; S320; S330; S340; S350, wherein said computer program is run on an electronic control unit 200 or the second control unit 210 / the computer 210 connected to the electronic control unit.

According to one embodiment, the invention relates to a computer program product directly storable in an internal memory of an electronic control unit 200 or another computer 210 connected to the electronic control unit, comprising a computer program P for performing the steps S310; S320; S330; S340; S350, when said computer program P is running on the controller / computer 200; 210.

The invention also relates to a motor-driven unit comprising an exhaust gas purification system 1; ll as described above.

Above, a first catalyst 250 and a second catalyst 252 have been described.

As mentioned above, the first catalyst and / or the second catalyst according to one embodiment may be divided into two or more partial catalysts. Furthermore, additional catalysts would be provided.

Furthermore, the above has a first injector device 270a; 270b and a second injector device 272 have been described. According to a variant, the first injector device 270a according to the first embodiment and the first injector device 270b according to the second embodiment are used together, both of which are arranged upstream of the first catalyst 250, which catalyst can be divided into several catalysts. According to a further variant, at least one further second injector device 272 is used, wherein these second injector devices are arranged to inject fuel downstream of the first catalyst 250 and upstream of the second catalyst 252, which catalyst 252 may be divided into several subcatalysts. According to a further variant, at least one further first injector device is used, arranged to inject fuel upstream of the first catalyst 250, which may be divided into several catalysts.

According to a variant of the invention, one or more intermediate catalysts are arranged between the first and second catalysts 250, 252, i.e. downstream of the first catalyst and upstream of the second catalyst, the first injector device 270a; 270b is arranged to inject fuel upstream of the first catalyst 250, further and at least one injector device is arranged to inject fuel upstream and intermediate catalyst, respectively, and the second injector device 272 is arranged to inject fuel upstream of the second catalyst 252 which is arranged upstream of filter 260.

The description of the preferred embodiments of the invention is not intended to be exhaustive or to limit the invention to the variations described. Obviously, many modifications and variations will occur to those skilled in the art.

Claims (12)

10 15 20 25 21 PATENT REQUIREMENTS An exhaust gas purification system (|; ll) with filter regeneration for an internal combustion engine, comprising an exhaust line (240) for conducting exhaust gases from said engine (230), a first catalyst (250) arranged in the exhaust line adjacent the engine (230), 230, a second catalyst (252) arranged in the exhaust line (240) downstream of the first catalyst (250), a filter device (260) arranged in the exhaust line downstream of the second catalyst (252), and an injector device (270a; 270b) arranged to regeneration cycle injecting a fuel into the exhaust line (240) upstream of the first exhaust flow heating catalyst which (250), injector device (272) arranged to inject a fuel into the exhaust line passes the first catalyst characterized by a second (240) between the first catalyst ( 250) and the second catalyst (252). Exhaust gas cleaning system (I) according to claim 1, wherein said first injector device is constituted by the engine (230) engine cylinder injector device (270a), arranged to inject said fuel after ordinary, for combustion in cylinder of the engine intended, injections. The exhaust gas purification system (II) according to claim 1, wherein said first injector device is an external injector device (270b). An exhaust gas purification system according to any one of claims 1-3, further comprising a control unit (200; 210) arranged to control the injection from said first injector device (270a; 270b) on the basis of dimensioning of the first and second catalyst (250, 252), the exhaust temperature before and / or after the catalysts and / or filter device (260). An exhaust gas purification system according to any one of claims 1-3, further comprising a control unit (200; 210) arranged to control the injection from said second injector device (272) on the basis of dimensioning of the first and second catalyst (250, 252), the exhaust gas temperature before and / or or after the catalysts and / or filter device (260) and the injection from the first injector device (270a; 270b). Engine-driven unit comprising an exhaust gas purification system (|; ll) according to any one of claims 1-5. A method for filter regeneration in an exhaust gas purification system of an internal combustion engine (230) comprising the step of: - injecting (S310) a fuel into the exhaust gas so that the exhaust gas in the exhaust gas flow is fuel enriched; characterized by the steps of: - by a first catalytic exothermic oxidation heating (S320) the fuel-enriched exhaust gas in the exhaust gas flow; - inject (S330) fuel into the heated fuel-enriched exhaust gas in the exhaust stream; - by a second catalytic exothermic oxidation, heating (S340) the fuel-enriched exhaust gas thus heated in the exhaust gas flow; passing (S350) the heated exhaust gas through the filter device, whereby a particle oxidation of particles of the filter device takes place so that a particle-purified filter device is obtained. The method of claim 7, wherein the step of injecting fuel into the exhaust gas so that the exhaust gas in the exhaust gas stream is fuel enriched is provided by the engine (230) engine cylinder injector device (270a). A method according to claim 7 or 8, wherein the amount of fuel in the step of injecting fuel into the exhaust gas so that the exhaust gas in the exhaust gas stream is fuel enriched is based on the flow and temperature of the exhaust gas. A computer program (P) for filter regeneration in an exhaust gas purification system of an internal combustion engine (230), said computer program comprising program code stored on a computer readable medium for performing the steps of claims 7-9, when said computer program is run on an electronic control unit (200 ) or another computer (210) connected to the electronic control unit. 23 A computer program product comprising a program code stored on a computer readable medium for performing the steps of claims 7-9, wherein said computer program is run on an electronic control unit (200) or another computer (210) connected to the electronic control unit. A computer program product directly stored in an internal memory of an electronic control unit (200) or another computer (210) connected to the electronic control unit, comprising a computer program (P) for performing the steps of claims 7-9, when said computer program (P ) runs on the computer (200; 210).