AT521454B1 - Process and arrangement of Otto engines with improved particle filtering I - Google Patents

Abstract

The invention relates to a method for operating a spark-ignition engine arrangement and a spark-ignition engine arrangement, the spark-ignition engine arrangement comprising a spark-ignition engine (1) and an exhaust gas after-treatment system (2) with a spark-ignition engine particle filter (4), the spark-ignition engine particle filter (4) having the from the spark-ignition engine (1) in its is loaded with particles emitted during the normal operating phase, with the gasoline engine particle filter (4) having its normal filtration efficiency when loaded with particles, with the gasoline engine particle filter (4) having a reduced filtration efficiency when it is fresh, in particular when it is regenerated or when it is new, the gasoline engine (1st ) is operated in a filling operation phase when the filtration efficiency of the gasoline engine particle filter (4) is reduced, with the gasoline engine (1) being operated in the filling operation phase in such a way that it emits higher particle emissions than in the normal operating phase, with particles entering the Otto engine in the filling operation phase or particle filter (4) are introduced in order to increase the filtration efficiency of the petrol engine particle filter (4), and the filling operation phase after reaching a sufficient or desired loading, in particular a sufficient or desired resulting filtration efficiency, of the petrol engine particle filter (4) is ended, the petrol engine (1) is operated in the filling operation phase in a lambda window which essentially corresponds to the lambda window of the normal operating phase and the gasoline engine (1) is operated in the normal operating phase in a lambda window around λ=1.

Description

description

METHOD AND GASOLINE ENGINE ARRANGEMENT WITH AN IMPROVED PARTICULATE FILTERING |

The invention relates to a method and an Otto engine assembly according to the preambles of the independent claims.

Different methods for operating an internal combustion engine are known from the prior art.

For example, methods for operating a diesel engine are known in which the particle-laden exhaust gas is filtered when penetrating a porous filter wall of an exhaust gas filter. During the filtration process, particles are retained by the filter medium of the exhaust gas filter and are deposited on it. As the filtration time increases, a particle layer of ash and/or soot that influences the filtration forms, in particular a small or very small amount of soot that is relevant for the gasoline engine particle filter - a so-called filter cake, which does increase the flow resistance, but also significantly improves the cleaning performance and/or Particle separation performance causes. Such methods for operating a diesel engine are known, for example, from US 20152858173 A1 and DE 102013210896 A1.

The filter walls of the exhaust gas filter can consist of different porous materials and can be made up of fibers or powder, for example. The fibers or the powder itself consist in particular of ceramics or metals. Classic ceramics are mullite, cordierite, silicon carbide (SiC) and aluminum titanate.

Due to the deposition of the particles on the surface or inside the filter wall of the exhaust gas filter, the flow resistance and thus also the differential pressure generated by the exhaust gas volume flow across the exhaust gas filter increase. When a differential pressure threshold value is reached - for example, when a certain particle mass is deposited on the filter wall of the exhaust filter - regeneration of the exhaust filter is initiated. If necessary, the natural regeneration potential is increased by active measures and/or special measures for regenerating the exhaust filter are initiated when a specific particle mass is reached that is deposited on the filter wall of the exhaust gas filter.

The exhaust gas filter is regenerated by burning the or parts of the combustible components of the accumulated particles. The active introduction of regeneration-promoting measures is necessary at the latest when the particle load causes a high exhaust gas back pressure to impede the exhaust gas emissions too much, especially when component limit values of the engine or the exhaust system are exceeded.

In particular, care must be taken to ensure that this is not thermally damaged by the burning of the particles in the petrol engine particle filter. In order to avoid permanent damage to the component, the exothermic potential in the event of combustion, i.e. when oxygen is present and at a corresponding temperature level, can be taken into account.

[0008] A measurement variable that can be used in addition to the raw emission modeling/filtration efficiency modeling and is easy to record, which allows the loading of the filter to be identified, is the absolute pressure before or the differential pressure before and after the exhaust gas filter. Since this absolute pressure or this differential pressure varies as a function of engine speed, load condition and loading quantity, these parameters are recorded in conventional methods in a characteristic map, in particular in an exhaust gas filter characteristic map. The monitoring of the absolute pressure or the differential pressure and the detection of passive and possibly active introduction and the control of the regeneration of the exhaust gas filter are carried out by the engine control of the internal combustion engine, in particular by the control unit of the internal combustion engine.

A method for operating an Otto engine arrangement is known from DE 102017115830 A1

famous.

According to the prior art, the exhaust gas filter has a reduced filtration efficiency when it is fresh, in particular when it is regenerated or when it is new, since in this state there is still no filter cake or no small/small amount of soot stored in the filter wall.

It is an object of the invention to provide a method and a gasoline engine arrangement with which a high filtration efficiency of the gasoline engine particle filter, in particular in terms of sustainability and emission minimization over a vehicle lifetime is made possible.

In particular, it is the object of the invention to overcome the disadvantages of the prior art. In addition, it is the object of the invention to come closer to the so-called vision of "zero impact emissions" in order to provide the end customer with an economical gasoline engine arrangement on the one hand and on the other hand to protect the environment by falling below the pollutant emission laws prescribed by the legislator, in particular the prescribed particle emissions.

The object according to the invention is achieved in particular by the features of the independent patent claims.

The invention relates to a method for operating a spark-ignition engine arrangement, the spark-ignition engine arrangement comprising a spark-ignition engine and an exhaust gas after-treatment system with a spark-ignition engine particle filter, the spark-ignition engine particle filter being loaded with the particles emitted by the spark-ignition engine in its normal operating phase, in particular with soot and/or with ash wherein the gasoline engine particulate filter has its normal filtration efficiency in a particulate-loaded condition, and wherein the gasoline engine particulate filter has a reduced filtration efficiency in a fresh condition, particularly in a regenerated condition or in a new condition.

According to the invention, it is provided that the Otto engine is operated in a filling operation phase when the filtration efficiency of the Otto engine particle filter is reduced, that the Otto engine is operated in the filling operation phase in such a way that it emits higher particle emissions than in the normal operating phase, that in the filling operation phase particles in be introduced into the gasoline engine particulate filter in order to increase the filtration efficiency of the gasoline engine particulate filter, and that the filling operation phase is terminated after a sufficient or desired loading, in particular a sufficient or desired resulting filtration efficiency, of the gasoline engine particulate filter has been reached.

The Otto engine arrangement can be the Otto engine arrangement of an internal combustion engine, in particular the Otto engine arrangement of a motor vehicle.

The method according to the invention is used with particular advantage for regenerating a particle filter. Use in a system that requires large amounts of carbon black is not intended. One goal should always be to achieve a positive overall emissions balance in terms of as few emissions as possible. This is not achievable in a system in which large amounts of soot are (must) be introduced into the particle filter.

It is further provided that the gasoline engine is operated in the filling operation phase in a lambda window that essentially corresponds to the lambda window of the normal operation phase, and that the gasoline engine is operated in the normal operation phase in a lambda window around A=1.

As a result, it may be possible that the exhaust gas generated by the gasoline engine is reduced in oxygen in the normal operating phase and in the filling operating phase and at most contains only small amounts of oxygen. In particular, the oxygen-reduced exhaust gas prevents unwanted regeneration of the gasoline engine particle filter in the normal operating phase and in the filling operating phase.

[0020] In particular, it is provided that the gasoline engine particle filter has its normal filtration efficiency, which is as high as possible in terms of sustainability, when it is loaded with particles. In addition, the filtration efficiency is increased in particular in such a way that the

During the filling operation phase with even lower filtration efficiency, the particle emissions after the particle filter are in a negligibly small ratio to the particle emission reduction potential to be achieved in the filter loaded with it, with consequently increased filtration efficiency through the filling operation phase in terms of sustainability and emission minimization. This is particularly preferably carried out as a result of previous regeneration conditions and/or as a result of possibly reduced filtration efficiency.

The gasoline engine can be operated in the normal operating phase and in the filling phase, with fuel and air being introduced into the combustion chambers of at least one cylinder of the gasoline engine in the normal operating phase and in the filling phase and converted to exhaust gas by combustion. In the normal operating phase and in the filling operating phase, the Otto engine is operated and/or regulated in a lambda window around )=1. This means that the Otto engine is optionally operated oscillating around a lambda value of 1.0 and in particular is operated and/or regulated with a lambda value A in the range from 0.9 to 1.1, preferably from 0.95 to 1.05 will. Provision can be made for the spark-ignition engine to be operated and/or regulated in its normal operating phase in phases or permanently under- or over-stoichiometrically, or rich or lean. A prerequisite for this may be that the exhaust gas aftertreatment components of the Otto engine arrangement allow the greatest possible conversion of raw emissions under these conditions. If necessary, it is provided that the gasoline engine emits an essentially low-oxygen exhaust gas in the normal operating phase and in the filling operating phase. Depending on the characteristics, an unwanted regeneration of the petrol engine particle filter can be prevented in the normal operating phase.

[0022] The exhaust aftertreatment system comprises at least one Otto engine particle filter. In particular, the exhaust gas generated in the gasoline engine flows through the gasoline engine particle filter of the exhaust aftertreatment system. The particles emitted by the Otto engine in its normal operating phase and in its filling operating phase, in particular the soot emitted by the Otto engine and/or the ash emitted by the Otto engine, are filtered by the Otto engine particle filter. The petrol engine particle filter is loaded with the particles emitted by the petrol engine.

Furthermore, the exhaust aftertreatment system can have a main catalytic converter, optionally a pre-catalytic converter and/or a secondary catalytic converter and/or a heated catalytic converter and/or an otto particle filter coated in particular in gaseous form for effective exhaust gas aftertreatment and/or a NOx storage catalytic converter and/or an SCR system and/or suitably coated Include exhaust aftertreatment component and / or a secondary air injection.

[0024] Since the particle residue from the retained particles that forms during filtration on the gasoline engine particle filter increases the cleaning performance and/or the particle separation capacity of the gasoline engine particle filter, the gasoline engine particle filter is only at its disposal after a certain particle load, in particular after a so-called basic load preferably maximum high normal filtration efficiency in terms of sustainability. Furthermore, what is known as a filter cake can form in the spark-ignition engine particle filter, in particular if the spark-ignition engine particle filter is loaded with large amounts of particles or large amounts of ash.

In the context of the present invention, the particle residue formed during the filtration on the gasoline engine particle filter is referred to as the particle residue from the retained particles. In particular, the gasoline engine particle filter has its normal filtration efficiency with a particle load of more than 0.9 g/l, for example with more than 0.1 g/l, in particular with a particle load in the range between 0.19 g/l to 3 g/l, preferably with a particle load in the range between 0 .5g/l to 3g/l.

[0026] The lower the particle load or the necessary basic load that is required for the spark-ignition engine particle filter to have its normal filtration efficiency, which is preferably as high as possible in terms of sustainability, the more efficiently the method according to the invention can be used. In particular, low-emission-oriented, less porous gasoline engine particle filters have a very low basic load, with the filtration efficiency of such gasoline engine particle filters also increasing significantly via the particle load, in particular via the soot load quantity, even with the smallest amounts of soot. In other words, it can

Duration in which the gasoline engine is operated in the filling operation phase, the shorter the lower the necessary basic loading of the gasoline engine particulate filter. As a result, it may be possible on the one hand to increase the filtration efficiency of the gasoline engine particle filter and on the other hand to reduce pollutant emissions.

It is noted here that the particle load required by the gasoline engine particle filter in order to be able to exhibit its normal filtration efficiency, which is preferably as high as possible in terms of sustainability, may be product-specific and in particular as a function of the substrate key data, such as in particular the porosity, the wall thickness, the Cell density and the like, and the coating that may be applied to the substrate, such as the so-called washcoat with its characterizing parameters, optionally supplemented by a noble metal load, is to be defined.

Optionally, it is provided that after a certain running time, the gasoline engine particle filter has a filtration efficiency that is largely independent of the soot load, in particular a permanently high filtration efficiency or permanently its normal filtration efficiency. This permanently high or permanently normal filtration efficiency can be caused by the increasing accumulation of ash in the gasoline engine particle filter over the running time, which is particularly dependent on the oil consumption and/or an oil specification of the engine. As soon as the gasoline engine particle filter is loaded with a certain amount of ash, it may no longer be necessary to operate the gasoline engine in the filling operation phase, since the gasoline engine particle filter exhibits its normal filtration efficiency even after it has been regenerated, in particular completely.

In contrast to this, the spark-ignition engine particle filter has a reduced filtration efficiency in a fresh state, in particular in a regenerated state or in a new state. In particular, the Otto engine particle filter has a reduced filtration efficiency compared to its normal filtration efficiency at a particle load which is smaller than the basic load of the respective Otto engine particle filter.

In the context of the present invention, a fresh state is understood to mean, in particular, a state of the gasoline engine particle filter in which the gasoline engine particle filter is essentially not loaded with particles, in particular unloaded, and has no particle residue from the retained particles, or one that is insufficiently effective as a filtration agent in terms of filtering having. In particular, the fresh state of the gasoline engine particulate filter is understood to mean the fully regenerated state or the brand new, not run-in state of the gasoline engine particulate filter.

That is, the filtration efficiency of the gasoline engine particulate filter in the fresh state is lower than the filtration efficiency of the gasoline engine particulate filter in the loaded state. This difference in filtration efficiency can essentially be caused by the fact that no filter cake has formed in or on the gasoline engine particle filter when it is fresh.

In order to increase the filtration efficiency, the gasoline engine is operated in the filling operation phase when the filtration efficiency of the gasoline engine particle filter is reduced. This means that the gasoline engine may be operated in the filling operation phase when the gasoline engine particle filter is in its fresh state. In particular, the Otto engine can be operated in the filling operation phase after the Otto engine particle filter has been exposed to regeneration conditions or when the Otto engine particle filter is new, in particular brand new.

In the filling operation phase, the gasoline engine is operated in such a way that the gasoline engine emits higher raw particle emissions than in the normal operating phase, so that possibly more soot and/or more ash is emitted from the gasoline engine in the filling operation phase than in the normal operating phase. However, it is always important that an overall balance of particle emissions is low despite the short-term higher emissions. With the method according to the invention, the particle emissions are only increased for a short time in order to achieve lower emissions over a normal period of time (average operation of an engine while driving or on the test bench). Consequently, the sustainability of Otto engines is increased.

It is important that the method according to the invention is carried out in such a way that an overall balance of particle emissions is significantly reduced despite the temporarily higher raw emissions. With the method according to the invention, the particle emissions are only increased for a short time in order to achieve significantly lower absolute emissions of the Otto engine arrangement after the exhaust aftertreatment in the sum of the filling and normal operating phase in real customer operation. Consequently, the sustainability of the Otto engine arrangement is increased within the meaning of the invention.

The particles emitted by the gasoline engine in the filling operation phase, in particular the soot and/or the ash, are filtered by the gasoline engine particle filter and increase the filtration efficiency of the gasoline engine particle filter. In particular, the filtration efficiency, in particular the cleaning performance and/or particle separation performance, of the petrol engine particle filter is increased in that the particle residue formed during filtration on the petrol engine particle filter from the retained particles blocks the open pores and/or channels of the petrol engine particle filter and/or a particle layer, in particular a filter cake, forms on the petrol engine particle filter, which itself becomes effective in filtration and thus increases that of the petrol engine particle filter.

If necessary, the filling operation phase of the spark-ignition engine is ended after a sufficient or desired loading of the spark-ignition engine particle filter with particles has been reached. In particular, it can be provided that the filling operation phase of the Otto engine is ended when the Otto engine particle filter has a sufficient or the desired, preferably maximum high filtration efficiency in terms of sustainability. As a result, the filtration efficiency of the gasoline engine particle filter can be controlled, regulated and/or adjusted.

If necessary, it is provided that the method is automated, in particular in a control unit of a motor vehicle and/or controlled and/or regulated by a control unit of a motor vehicle.

If necessary, it is provided that the decision as to whether a filling operation phase is carried out or not is made by the engine control of the internal combustion engine, in particular by the control unit of the internal combustion engine, and this decision is based on the values preferably stored in the engine control, preferably in the sense of sustainability at most high filtration efficiency information as a function of soot and/or ash loading.

If necessary, it is provided that the particles introduced into the petrol engine particle filter in the filling operation phase are generated by the petrol engine.

[0040] This means that the particles introduced into the gasoline engine particle filter in the filling operation phase may be produced by the gasoline engine.

If necessary, it is provided that the increase in the particle emissions of the Otto engine in the filling operating phase takes place through active adjustment of engine operating parameters that deviates from the normal operating phase.

In particular, it can be provided to increase the particle emissions of the Otto engine in the filling operation phase by a particularly temporary active adjustment of engine operating parameters in terms of sustainable emission-optimal use of the method according to the invention under suitable operating conditions. The particle emissions occurring during the filling phase with even lower filtration efficiency are therefore in a negligibly small ratio to the particle emission reduction potential to be achieved by the filter with increased filtration efficiency through the filling phase in terms of sustainability and emission minimization, especially after the particle filter.

If necessary, it is provided that the increase in the particle emissions of the Otto engine in the filling operation phase takes place through an actively increased wetting of the combustion chamber walls and/or the piston with the fuel introduced into the at least one combustion chamber of the Otto engine, and/or that the increase in particle emissions takes place of the Otto engine in the filling operation phase by increasing the droplet size of the fuel introduced into at least one combustion chamber of the Otto engine, and/or that the increase in the particle emissions of the

Otto engine in the filling operation phase by changing the injection time or the injection points of the fuel introduced into at least one combustion chamber of the Otto engine, and/or that the particle emissions of the Otto engine are increased in the filling operation phase by multiple injections, in particular with high Shares in the very early intake stroke and/or very late compression stroke phase of the fuel introduced into at least one combustion chamber of the Otto engine, and/or that the particle emissions of the Otto engine are increased in the filling operation phase by lowering the fuel pressure of the fuel introduced into at least one combustion chamber of the Otto engine takes place, and/or that the increase in the particle emissions of the Otto engine in the filling operation phase takes place through an active increased wetting of the combustion chamber walls and/or the piston that is proportional to the injection quantity, in particular the load level, w which is or are caused by a load point shift, in particular an increase in the load point, preferably by measures to reduce engine efficiency, such as retarding the ignition angle, with the fuel introduced into the at least one combustion chamber of the gasoline engine, and/or that the increase in particle emissions from the gasoline engine in the filling phase is caused by a Wetting of a surface with the fuel introduced into the at least one combustion chamber of the Otto engine takes place at a reduced surface temperature of the combustion chamber walls and/or the piston, and in particular by wetting the piston crown with an oil film, and is preferably caused by a specifically activated piston spray nozzle, and/or that the particle emissions of the Otto engine are increased in the filling operating phase by changing the air-fuel ratio to preferably sub-stoichiometric, the change in the air-fuel ratio being in particular after an overrun cut-off phase in combination with a targeted emptying of the oxygen accumulator of a main catalytic converter, a secondary catalytic converter and/or the gasoline engine particle filter, which is in particular coated with an oxidation catalytic converter coating.

In particular, in the filling operation phase, parameters such as the injection time, the injection mode and/or the fuel pressure in the fuel lines, the air-fuel ratio or the piston spray nozzle flow rate are actively adjusted to increase the particle emissions of the Otto engine, and/or its operating point in the direction of higher load and thus higher fuel quantity shifted.

If necessary, provision is made to inject fuel once or several times into the cylinders of the Otto engine in the filling operation phase of the Otto engine and to adjust the preferably first of the injection time points, in particular in the advance direction, in order to accelerate the piston, which is preferably still close to top dead center, and in particular the Combustion chamber walls to be actively wetted with fuel and/or the preferably last of the injection timing/s to be adjusted in particular in the late direction in order to bring about targeted incomplete diffusion combustion under a lack of oxygen caused by the timing. This can lead to insufficient fuel homogenization or combustion of a locally rich mixture in the combustion chambers of at least one cylinder of the Otto engine. As a result, more particles, in particular more soot, can be produced in the petrol engine in the filling operating phase than in the normal operating phase.

If necessary, provision is made to lower the fuel pressure in the fuel lines, which supply fuel to the Otto engine, in the filling operation phase of the Otto engine. This can lead to longer injection times, which makes it easier to wet the surfaces in the combustion chamber with fuel due to the increased penetration depth of the fuel jets, and which means that more particles, especially more soot, can be produced in the filling operation phase compared to the normal operation phase. If necessary, it is intended to cause the same effect by increasing the load.

If necessary, it is provided that the increase in the particle emissions of the Otto engine in the filling operation phase takes place through an active increased wetting of the combustion chamber walls and/or the piston that is proportional to the injection quantity, in particular the load level. This increased use of the combustion chamber walls and/or the piston, which is proportional to the load level, can be achieved by shifting the load point, in particular by increasing the load point, preferably by

engine efficiency lowering measures, such as an ignition angle retardation, are caused by the fuel introduced into the at least one combustion chamber of the gasoline engine.

If necessary, it is provided that the increase in the particle emissions of the Otto engine in the filling operation phase is achieved by wetting a surface with the fuel introduced into the at least one combustion chamber of the Otto engine, with a reduced surface temperature of the combustion chamber walls and/or the piston, and in particular by Wetting of the piston crown with an oil film takes place.

This can preferably be caused by a specifically activated piston injection nozzle.

If necessary, provision is made for the particle emissions of the Otto engine to be increased in the filling operating phase by changing the air-fuel ratio to preferably sub-stoichiometric. In particular, it can be provided that in the filling operating phase the oxygen accumulator of a main catalytic converter, a secondary catalytic converter and/or the gasoline engine particle filter, which is in particular coated with an oxidation catalytic converter coating, is emptied. By operating the Otto engine in the filling operating phase, the oxygen contained in a catalytic converter can be reduced, in particular eliminated. By operating the gasoline engine in the filling phase, it may be possible to increase the efficiency of a catalytic converter on the one hand and to load the gasoline engine particle filter with particles on the other.

If necessary, in the sense of the sustainable emission-optimal application of the strategy according to the invention, it is provided that the increase in the particle emissions of the gasoline engine in the filling operating phase by changing engine operating parameters, but at least in combination with a change in the air-fuel ratio to preferably substoichiometric, in particular after oxygen-rich overrun phases. In particular, it can be provided that parallel to and/or during the filling operation phase, the oxygen accumulator of a pre-catalyst, main catalyst and/or secondary catalyst and/or the gasoline engine particle filter coated in particular with an oxidation catalyst coating is emptied, previously filled in the oxygen-rich boost. By operating the Otto engine in the filling operating phase, the oxygen contained in a catalytic converter can be reduced, in particular eliminated. By operating the gasoline engine in the filling operation phase, especially after oxygen-rich overrun phases, it can be possible in combination to quickly increase the efficiency of a catalytic converter again in terms of sustainability and at the same time to load the gasoline engine particle filter with particles and thus also to increase its efficiency. so that the maximum normal filtration efficiency in terms of sustainability is quickly restored.

If necessary, the change in the engine operating parameters, such as the fuel injection and/or the injection mode, can be adapted to the quantity of particles to be produced, in particular the quantity of soot.

If necessary, it is provided that the Otto engine arrangement for the regeneration of the Otto engine particle filter is operated in a regeneration mode in which combustible components of the particles are burned in the Otto engine particle filter.

In particular, the Otto engine arrangement can be operated in the regeneration mode in such a way that the oxygen content and the temperature level of the exhaust gas result in a regeneration, an active or passive regeneration, of the Otto engine particle filter.

The regeneration of the gasoline engine particle filter takes place in the regeneration mode by the combustion of combustible components of the particles located in the gasoline engine particle filter. In particular, regeneration, in particular active regeneration, of the gasoline engine particle filter may become necessary if the particle load causes a high exhaust gas back pressure to impede exhaust gas emissions too much or component limit values are exceeded. In particular, a regeneration of the gasoline engine particle filter may be necessary if, for example, exhaust gas aftertreatment system-specific parameters such as a gasoline engine particle filter-specific parameter, such as a differential pressure threshold or a loading quantity, is exceeded.

On the one hand, the regeneration can reduce the exhaust back pressure caused by the particle loading in the gasoline engine particle filter. On the other hand, the combustion of combustible components of the particles deposited on the gasoline engine particle filter reduces or removes the particle residue and thus the filtration efficiency of the gasoline engine particle filter is significantly reduced.

If necessary, it is provided that the Otto engine arrangement for the regeneration of the Otto engine particle filter is operated in a regeneration mode, the Otto engine arrangement being operated in the regeneration mode in order to increase the soot burn-off and the regeneration potential of the Otto engine particle filter in such a way that a temperature of over 500° C. prevails in the Otto engine particle filter or the exhaust gas flowing through the gasoline engine particulate filter has a temperature above 500°C and such that the gas or exhaust gas flowing through the gasoline engine particulate filter contains oxygen.

[0058] A specific minimum temperature is generally required for the combustion of combustible components of the accumulated particles in the gasoline engine particle filter. In all embodiments, the regeneration is preferably an exothermic oxidation.

To carry out the regeneration, the Otto engine is preferably operated in the regeneration mode in such a way that the Otto engine particle filter, the exhaust gas flowing through the Otto engine particle filter and/or the particles located in the Otto engine particle filter have a temperature greater than the regeneration temperature and in particular a temperature above 500° C., or exhibit. Furthermore, the Otto engine can be operated in the regeneration mode in such a way that the exhaust gas flowing through the Otto engine particle filter contains oxygen.

If necessary, it is provided that the Otto engine arrangement is operated in the regeneration mode in order to increase the soot burn-off and/or the regeneration potential of the Otto engine particle filter in such a way that oxygen is present in the Otto engine particle filter and the Otto engine particle filter has a temperature of over 500°C. In the regeneration mode, the gasoline engine can be operated in such a way that the stated conditions, in particular the temperature of the gasoline engine particulate filter, the temperature of the exhaust gas flowing through the gasoline engine particulate filter, the temperature of the particles in the gasoline engine particulate filter and/or the oxygen content in the gasoline engine particulate filter, individually or in combination, have a positive effect will.

If necessary, it is provided that the filling operation phase immediately follows a regeneration of the gasoline engine particle filter.

[0062] The regeneration of the gasoline engine particle filter can in particular occur temporarily, particularly preferably in oxygen-rich overrun phases, but also continuously or be actively carried out and/or promoted.

If necessary, the Otto engine is operated in its filling operating phase after a regeneration, in particular an active or passive one, of the Otto engine particle filter. In particular, the filling operation phase can follow an active or passive regeneration of the gasoline engine particle filter in terms of maximizing the robustness of emissions and/or be activated by the detection of such a regeneration. In particular, the filling operation phase that follows the regeneration can be an integral part of a regeneration process of the spark-ignition engine particle filter.

In particular, it can be provided that the operation of the gasoline engine in the filling phase on the one hand loads the gasoline engine particle filter with particles and on the other hand removes the oxygen stored in the catalysts of the exhaust gas aftertreatment system in the unfired overrun phase.

If necessary, it is provided that the control device of the Otto engine assembly detects or calculates an efficiency parameter that allows conclusions to be drawn about the filtration efficiency, the efficiency parameter in particular the loading quantity of the Otto engine particle filter with soot and/or ash, the operating time of the Otto engine particle filter since the last regeneration

on conditions of the petrol engine particle filter, the distance covered by the petrol engine particle filter since the last regeneration of the petrol engine particle filter and/or the pressure difference caused by the petrol engine particle filter before and after the petrol engine particle filter and/or the back pressure in front of the petrol engine particle filter, and that the control unit carries out a regeneration of the petrol engine particle filter when the filtration efficiency is above a defined regeneration threshold.

If necessary, it is provided that the filling operation phase is carried out after the production of the Otto engine arrangement, in particular in the course of the end-of-line test of the vehicle production or after a service regeneration in a car workshop.

In particular, the invention relates to a spark-ignition engine arrangement, the spark-ignition engine arrangement being suitable and/or set up for carrying out the method according to the invention.

In the context of the present invention, a front region of an exhaust gas aftertreatment component is to be understood as meaning the region through which the exhaust gas flows earlier in the flow direction of the exhaust gas in the respective exhaust gas aftertreatment component. In particular, this can be the area through which the exhaust gas enters the respective exhaust gas aftertreatment component.

In the context of the present invention, a rear region of an exhaust gas aftertreatment component is understood to mean the region through which the exhaust gas later flows in the flow direction of the exhaust gas in the respective exhaust gas aftertreatment component. In particular, this can be the area through which the exhaust gas exits from the respective exhaust gas aftertreatment component.

[0070] Further features according to the invention can be found in the claims, the description of the exemplary embodiments and the figures.

The invention will now be explained further using the example of exemplary, non-exclusive and/or non-limiting embodiments.

1 shows a schematic diagram of a first embodiment of the spark-ignition engine arrangement according to the invention.

Unless otherwise indicated, the reference numbers correspond to the following components:

Gasoline engine 1, exhaust aftertreatment system 2, main catalytic converter 3, gasoline engine particle filter 4, turbocharger 5, throttle valve 6, compressor 7, turbine 8 and high-pressure EGR line 9.

1 shows a schematic graphic representation of a first embodiment of a spark-ignition engine arrangement according to the invention, which is suitable and/or set up for carrying out the method according to the invention.

In this embodiment, the spark-ignition engine arrangement comprises a spark-ignition engine 1 and an exhaust gas after-treatment system 2. The exhaust gas after-treatment system 2 includes a main catalytic converter 3 and a gasoline engine particle filter 4 arranged downstream of the main catalytic converter 3. In this embodiment, the main catalytic converter 3 is designed as a 3-way catalytic converter and is installed directly in the Connection to the turbine 8 of the turbocharger 5, in particular close to the engine, arranged.

In an embodiment that is not shown, the exhaust gas aftertreatment system 2 comprises only one gasoline engine particle filter 4 . In a further embodiment that is not shown, the exhaust aftertreatment system 2 includes a main catalytic converter 3, a gasoline engine particle filter 4.

Furthermore, the Otto engine arrangement of FIG. 1 comprises a turbocharger 5, a throttle valve 6 and a high-pressure EGR line 9 of a high-pressure EGR system of the Otto engine arrangement. The turbocharger 5 comprises a compressor 7 and a turbine 8.

The Otto engine arrangement is in a normal operating phase and in a filling operation

phase operated. Fuel is supplied to the Otto engine 1 in the normal operating phase and in the filling operating phase. In the normal operating phase and in the filling operating phase, the fuel is converted with air to form an exhaust gas.

In the normal operating phase, the Otto engine 1 is operated and/or regulated in a lambda window around A=1. This means that the Otto engine is optionally operated oscillating around a lambda value of 1.0 and in particular operated and/or regulated with a lambda value in the range from 0.9 to 1.1, preferably from 0.95 to 1.05 will. According to this specific embodiment, provision can be made for Otto engine 1 to be operated rich or lean and/or regulated in phases or permanently in its normal operating phase.

According to this embodiment, the exhaust gas emitted by the Otto engine 1 in the normal operating phase and in the filling operating phase is oxygen-reduced, essentially oxygen-free. As a result, regeneration, in particular active regeneration, of the gasoline engine particle filter 4 is prevented in the normal operating phase and in the filling operating phase.

In the normal operating phase, the gasoline engine particle filter 4 is loaded by the particles emitted by the gasoline engine 1, in particular with soot and/or with ash. Only after the spark-ignition engine particle filter 4 has a sufficient load, in particular a sufficient particle residue or a sufficient particle residue thickness, does the spark-ignition engine particle filter 4 have its normal, maximum filtration efficiency in terms of sustainability. According to this embodiment, the gasoline engine particle filter 4 has its normal filtration efficiency when the gasoline engine particle filter has reached its specific minimum load for achieving its normal filtration efficiency, the so-called basic load. If the spark-ignition engine particle filter has a particle load which is less than its base load, the filtration efficiency of the spark-ignition engine particle filter is reduced compared to the normal filtration efficiency of the spark-ignition engine particle filter.

In contrast to this, the gasoline engine particle filter 4 in the fresh state, ie in the regenerated or in the new state, has a filtration efficiency that is reduced compared to the normal filtration efficiency. This difference in the filtration efficiency, in particular in the cleaning performance and/or particle separation performance of the gasoline engine particle filter 4, can be attributed to an insufficiently formed particle residue.

In the regenerated state, the gasoline engine particle filter 4 has at least in sections no or only a very thin particle residue, since the combustible components of the particles accumulated in the gasoline engine particle filter 4 were burned by the regeneration.

On the one hand, the regeneration of the gasoline engine particle filter 4 lowers the exhaust gas back pressure, which was caused by the particle loading in the gasoline engine particle filter 4 . On the other hand, the combustion of combustible components of the particles deposited on the gasoline engine particle filter 4 reduces or removes the particle residue at least in sections, as a result of which the filtration efficiency of the gasoline engine particle filter 4 is significantly reduced.

In the new, in particular brand-new, not run-in state, the gasoline engine particle filter 4 has no particle residue.

To carry out the regeneration of the gasoline engine particle filter 4, according to this embodiment, the gasoline engine 1 is operated in the regeneration mode in such a way that the gasoline engine particle filter 4, the exhaust gas flowing through the gasoline engine particle filter 4 and/or the particles in the gasoline engine particle filter have a temperature greater than the regeneration temperature, and in particular a temperature above 500°C. Furthermore, the gas flowing through the gasoline engine particle filter contains oxygen during the regeneration of the gasoline engine particle filter.

According to this embodiment, the Otto engine 1 is operated immediately after a regeneration of the Otto engine particle filter 4 in the filling operation phase. This means that the Otto engine 1 immediately after the Otto engine arrangement is operated in the regeneration mode,

is operated in the filling operation phase.

The Otto engine 1 is operated in the filling operation phase when the filtration efficiency of the Otto engine particle filter 4 is reduced. This means that the Otto engine 1 is operated in the filling operation phase when the Otto engine particle filter 4 is in its fresh state and, in particular, has been regenerated or is brand new.

In the filling operating phase, the Otto engine 1 is operated in such a way that the Otto engine 1 emits more particles than in the normal operating phase. The particles emitted by the Otto engine 1 in the filling operation phase, in particular the emitted soot and/or the emitted ash, are introduced into the Otto engine particle filter 4 to increase the filtration efficiency. In particular, a particle residue is formed by the introduced or filtered particles in the gasoline engine particle filter 4, which increases the filtration efficiency.

[0090] The increase in particle emissions from the Otto engine 1 in the filling operating phase takes place through active adjustment of engine operating parameters that deviates from the normal operating phase. In particular, the particle emissions of the Otto engine 1 in the filling operating phase are increased according to this embodiment by increasing the droplet size of the fuel introduced into at least one combustion chamber of the Otto engine 1 .

After reaching a sufficient or desired loading, in particular a sufficient filtration efficiency, the filling operation phase is ended.

The exhaust gas generated in the gasoline engine in the normal operating phase and in the filling operation phase first flows through the turbine 8 of the turbocharger 5, then through the main catalytic converter 3 and then through the gasoline engine particle filter 4, and possibly other exhaust gas aftertreatment components, before it escapes into the environment.

The particles generated by the Otto engine 1 are filtered by the Otto engine particle filter 4 and accumulate on it. Due to the accumulation of the particles, a particle residue is built up in the petrol engine particle filter 4, which significantly increases the filtration efficiency, in particular the cleaning and the particle separation performance.

With this exemplary configuration, the effects of the present invention can be obtained.

The invention is not limited to the illustrated embodiments, but includes any method and any Otto engine arrangement according to the following claims.

Claims (9)

patent claims 1. Method of operating a spark ignition engine arrangement, - wherein the Otto engine arrangement comprises a Otto engine (1) and an exhaust gas after-treatment system (2) with a Otto engine particle filter (4), - wherein the gasoline engine particle filter (4) is loaded with the particles emitted by the gasoline engine (1) in its normal operating phase, in particular with soot and/or with ash, - wherein the petrol engine particle filter (4) has its normal filtration efficiency when loaded with particles, - and wherein the gasoline engine particle filter (4) has a reduced filtration efficiency in a fresh state, in particular in a regenerated state or in a new state, - wherein the Otto engine (1) is operated in a filling operating phase when the filtration efficiency of the Otto engine particle filter (4) is reduced, - wherein the gasoline engine (1) is operated in the filling operation phase in such a way that it emits higher particle emissions than in the normal operation phase, - Particles being introduced into the petrol engine particle filter (4) in the filling operation phase in order to increase the filtration efficiency of the petrol engine particle filter (4), - and wherein the filling operation phase is ended after reaching a sufficient or desired loading, in particular a sufficient or desired resulting filtration efficiency, of the gasoline engine particle filter (4), characterized, - That the gasoline engine (1) is operated in the filling operation phase in a lambda window that essentially corresponds to the lambda window of the normal operating phase, - and that the gasoline engine (1) is operated in a lambda window around A=1 in the normal operating phase. 2. The method as claimed in claim 1, characterized in that the particles introduced into the petrol engine particle filter (4) in the filling operation phase are generated by the petrol engine (1). 3. The method according to claim 1 or 2, characterized in that the increase in the particle emissions of the Otto engine (1) in the filling operation phase takes place through active adjustment of engine operating parameters that deviates from the normal operating phase. 4. The method according to any one of the preceding claims, characterized in that - That the increase in the particle emissions of the Otto engine (1) in the filling phase takes place through an actively increased wetting of the combustion chamber walls and/or the piston with the fuel introduced into the at least one combustion chamber of the Otto engine (1), and/or that the increase in the particle emissions of the Otto engine (1) in the filling operation phase by increasing the droplet size of the fuel introduced into at least one combustion chamber of the Otto engine (1), - and/or that the particle emissions of the Otto engine (1) are increased in the filling phase by changing the injection timing or the injection points of the fuel introduced into at least one combustion chamber of the Otto engine (1), - and/or that the increase in the particle emissions of the Otto engine (1) in the filling operation phase by a multiple injection, specifically modified in particular for the purpose of the filling operation phase, in particular with high proportions in the very early suction stroke and/or in the very late compression stroke phase, of at least fuel introduced into a combustion chamber of the Otto engine (1), - and/or that the particle emissions of the Otto engine (1) are increased in the filling operation phase by lowering the fuel pressure of the fuel introduced into at least one combustion chamber of the Otto engine (1), - and/or that the increase in the particle emissions of the Otto engine (1) in the filling operation phase takes place through an active increased wetting of the combustion chamber walls and/or the piston proportional to the bit quantity, in particular the load level, which is caused by a load point shift, in particular an increase in the load point, preferably by Measures to reduce engine efficiency, such as retarding the ignition angle ment caused by the fuel introduced into the at least one combustion chamber of the Otto engine (1), - and/or that the increase in the particle emissions of the Otto engine (1) in the filling operation phase by wetting a surface with the fuel introduced into the at least one combustion chamber of the Otto engine (1) at a reduced surface temperature of the combustion chamber walls and/or the piston, and in particular by wetting the piston crown with an oil film, and is preferably caused by a specifically activated piston spray nozzle, - and/or that the particle emissions of the Otto engine (1) are increased in the filling phase by changing the air-fuel ratio to preferably sub-stoichiometric, with the change in the air-fuel ratio taking place in particular after an overrun cut-off phase in combination with targeted emptying of the oxygen accumulator of a main catalyst, a secondary catalyst and/or the gasoline engine particle filter (4), which is in particular coated with an oxidation catalyst coating. 5. The method according to any one of the preceding claims, characterized in that the Otto engine arrangement for regenerating the Otto engine particle filter (4) is operated in a regeneration mode in which combustible components of the particles in the Otto engine particle filter (4) are burned. 6. The method according to any one of the preceding claims, characterized in that - that the Otto engine arrangement for the regeneration of the Otto engine particle filter (4) is operated in a regeneration mode, - wherein the Otto engine arrangement is operated in the regeneration mode to increase the soot burn-off and the regeneration potential of the Otto engine particle filter (4) in such a way that a temperature of over 500° C. prevails in the Otto engine particle filter (4) or the exhaust gas flowing through the Otto engine particle filter (4) has a temperature of over has 500°C, - And in such a way that the gas or exhaust gas flowing through the gasoline engine particle filter (4) contains oxygen. 7. The method according to any one of the preceding claims, characterized in that the filling operation phase immediately follows a regeneration of the gasoline engine particle filter (4). 8. The method according to any one of the preceding claims, characterized in that the filling operation phase is carried out following the manufacture of the Otto engine arrangement, in particular during the end-of-line test of vehicle manufacture or after a service regeneration in a car workshop. 9. Otto engine arrangement, characterized in that the Otto engine arrangement for carrying out the method according to one of claims 1 to 8 is suitable and / or set up. 1 sheet of drawings