KR20220037963A - Method and device for diagnosing a coated otto particle filter of an exhaust tract of an internal combustion engine - Google Patents

Abstract

The present invention relates to a method and a device for diagnosing the coated gasoline particulate filter (140) of the exhaust pipe (100) of an internal combustion engine. The exhaust pipe (100) comprises: a coated gasoline particulate filter (140); a first NO_x-/NH_3-sensor (130) arranged upstream of the gasoline particulate filter (140) in an exhaust gas flow direction; and a second NO_x-/NH_3-sensor (150) arranged downstream of the gasoline particulate filter (140) in the exhaust gas flow direction. In this case, the method comprises the following steps of: operating the internal combustion engine in which an exhaust gas flows through the exhaust pipe (100); detecting a first measurement signal (342) by using the first NO_x-/NH_3-sensor (130) characterizing the NH_3-concentration in the exhaust gas upstream of the gasoline particulate filter (140); detecting a second measurement signal (352) by using the second NO_x-/NH_3-sensor (150) characterizing the NH3-concentration in the exhaust gas downstream of the gasoline particulate filter (140); and evaluating the first measurement signal (342) and the second measurement signal (352) to diagnose the coated gasoline particulate filter (140). Therefore, the method and the device can perform a reliable diagnosis on the gasoline particulate filter of the exhaust pipe of the internal combustion engine.

Description

METHOD AND DEVICE FOR DIAGNOSING A COATED OTTO PARTICLE FILTER OF AN EXHAUST TRACT OF AN INTERNAL COMBUSTION ENGINE

The present disclosure relates to a method and apparatus for diagnosing a coated gasoline particulate filter in an exhaust gas duct of an internal combustion engine, wherein the exhaust gas duct of a coated gasoline particulate filter comprises a coated gasoline particulate filter, the coating in the exhaust gas flow direction a first NOx-/NH3-sensor arranged upstream of the used gasoline particulate filter, and a second NOx-/NH3-sensor arranged downstream of the coated gasoline particulate filter in an exhaust gas flow direction.

The exhaust gas pipe of an internal combustion engine is designed to after-treat the exhaust gas originating from the combustion chamber and to guide the exhaust gas into the surrounding environment. In the case of exhaust gas aftertreatment, for example, pollutants are filtered out or reduced from the exhaust gas. Due to increasingly stringent regulations of different authorities, more and more gasoline engines are equipped with particulate filters, as a result particulates originating from the exhaust gases are bound within the particulate filters, preventing the particulates from entering the surrounding environment. Gasoline particulate filters filter a significant portion of the particulates produced during combustion from the exhaust. Additionally, the exhaust pipe may be equipped with an exhaust gas catalytic converter that reduces pollutants such as hydrocarbons, carbon monoxide and nitrogen oxides to harmless exhaust gas components such as water and carbon dioxide.

The function of the gasoline particulate filter is usually realized by evaluating the differential pressure signal through the gasoline particulate filter. However, such conventional methods for monitoring the functioning of gasoline particulate filters are inaccurate and cannot reliably detect potential damage or defects within gasoline particulate filters. Due to unreliable diagnostics of gasoline particulate filters for damage, authorities have not yet defined stringent particulate count thresholds globally as there has so far not been a robust solution to detect damaged gasoline particulate filters. .

Therefore, it is an object of the present disclosure to provide a method and apparatus capable of performing reliable diagnosis of a gasoline particulate filter in an exhaust gas pipe of an internal combustion engine.

The above problem is solved by the features of the independent patent claims. Preferred embodiments of the present disclosure are specified in the dependent claims.

According to the present disclosure, a method for diagnosing a coated gasoline particulate filter of an exhaust gas pipe of an internal combustion engine comprises a coated gasoline particulate filter, a first NOx-/ arranged upstream of the coated gasoline particulate filter in an exhaust gas flow direction. an NH3-sensor, and a second NOx-/NH3-sensor arranged downstream of the coated gasoline particulate filter in the exhaust gas flow direction. The NOx-/NH3-sensor may comprise a NOx-sensor or an NH3-sensor (ammonia sensor). Accordingly, it originates from the internal combustion engine and flows through the exhaust gas duct where the exhaust gas first passes through the first NOx-/NH3- sensor and then into the coated gasoline particulate filter, after which the second NOx-/NH3 - pass through the sensor Coated gasoline particulate filters are designed to trap particulates from exhaust gases. According to the present disclosure, in a first method step the internal combustion engine is operated, whereby the exhaust gas flows through the exhaust gas pipe, since the air-fuel mixture is combusted in the combustion chamber of the internal combustion engine, whereby the exhaust gas pipe This is because exhaust gases that pass through and are released into the surrounding environment are produced. In this exhaust gas there may be particulates that must be filtered out by a coated gasoline particulate filter.

According to the present disclosure, in a second step, a first measurement signal characterizing the NH3- concentration in the exhaust gas upstream of the gasoline particulate filter is detected using a first NOx-/NH3- sensor. Accordingly, in the first measurement signal, the NH3-concentration in the exhaust gas upstream of the coated gasoline particulate filter can be detected. The NOx-sensor detects the measurement signal with NH3 cross-sensitivity, from which the NH3-concentration can be determined. According to the present disclosure, in a further step, a second measurement signal characterizing the NH3- concentration in the exhaust gas downstream of the gasoline particulate filter is detected using a second NOx-/NH3- sensor. Accordingly, the NH3 concentration in the exhaust gas downstream of the coated gasoline particulate filter can be detected using the second measurement signal. According to the present disclosure, in another step, the first measurement signal and the second measurement signal are evaluated for diagnosing the coated gasoline particulate filter. A coated gasoline particulate filter in accordance with the present disclosure converts gaseous pollutants, particularly hydrocarbons, carbon monoxide and nitrogen oxides, originating from exhaust gases in parallel with particulate filtration. In order to effect conversion even in a slightly excess or slightly oxygen state, the coating of a gasoline particulate filter, according to one embodiment, typically has oxygen storage properties.

If in the first measurement signal of the first NOx-/NH3-sensor it can be seen, for example, an increase in the NH3-concentration in the exhaust gas upstream of the coated gasoline particulate filter, then the gasoline particulate filter coated with more NH3 accordingly flows into me The conversion capability of the coated gasoline particulate filter allows the NH3 entering the gasoline particulate filter to be converted and thereby reduced. Accordingly, unless the gasoline particulate filter is damaged, the NH3-concentration varies across the coated gasoline particulate filter. Accordingly, using the second measurement signal, a difference in NH 3 - concentration due to the conversion characteristics of the coated gasoline particulate filter can be detected. The first measurement signal and the second measurement signal can be used to diagnose a gasoline particulate filter coated in accordance with the present disclosure, whereby a conclusion can be drawn as to whether conversion of NH3 has taken place in the gasoline particulate filter. . If the gasoline particulate filter is damaged, a portion of the NH3 will flow through the gasoline particulate filter undisturbed, a situation as can be seen in the second measurement signal. Accordingly, according to the present disclosure, the diagnosis of the gasoline particulate filter can be carried out in a very simple and accurate type and manner. Due to this, damage such as cracks due to high thermal stress in the coated gasoline particulate filter can be detected.

According to an embodiment, for evaluation the first measurement signal is compared with the second measurement signal, and if an increase in the NH3- concentration in the first measurement signal and in the second measurement signal is detected almost simultaneously, the coated gasoline particulate The filter is recognized as damaged. If the coated gasoline particulate filter is damaged, NH3 can flow almost unimpeded through the coated gasoline particulate filter, thereby reducing the NH3 concentration detected in the measurement signal of the first NOx-/NH3-sensor. The increase almost simultaneously follows the increase in the NH3- concentration detected in the second measurement signal of the second NOx-/NH3-sensor. Accordingly, in this way, a diagnosis of the gasoline particulate filter associated with damage to the gasoline particulate filter can preferably be recognized simply but also accurately. Comparing the second measurement signal with the first measurement signal may include calculating efficiency, difference or filtering, according to an embodiment.

According to one embodiment, the coated gasoline particulate filter is capable of storing oxygen used for conversion of NH3, in which case the method is only carried out if a predetermined amount of oxygen is present in the coated gasoline particulate filter. NH3 can be converted by oxygen in the coated gasoline particulate filter. If no oxygen is present in the coated gasoline particulate filter for conversion, then also no or little NH3 is converted, resulting in NH3 passing through the coated gasoline particulate filter unconverted/impeded. will flow Accordingly, if this method is carried out when no oxygen is present in the gasoline particulate filter, NH3 flows through the gasoline particulate filter unimpeded or unconverted, whereby damage to the gasoline particulate filter is diagnosed by this method. can be Situations like this should be avoided. Accordingly, this method should only be carried out if a predetermined amount of oxygen (eg 50% of the maximum possible oxygen concentration) is present in the coated gasoline particulate filter, for the reason that only such cases have already been described. This is because NH3 is converted in the coated gasoline particulate filter as described above. In the gasoline particulate filter coated with NH3, it is converted by oxygen, so that the measurement signal of the first NOx-/NH3-sensor is differentiated from the measurement signal of the second NOx-/NH3-sensor. This distinction can be interpreted to mean that the gasoline particulate filter is not damaged. If the increase in the measured signal of the NOx-/NH3-sensor directly follows the increase in the second measured signal of the second NOx-/NH3-sensor despite the presence of sufficient oxygen, then the gasoline particulate filter is damaged accordingly. Alternatively, a conclusion can be drawn about the reduction in efficiency. According to this embodiment, the accuracy of this method can be further advantageously increased.

According to one embodiment, the exhaust gas pipe of the internal combustion engine has an exhaust gas catalytic converter arranged upstream of the first NOx-/NH3- sensor, so that the exhaust gas first flows through the exhaust gas catalytic converter, In this case, since the operation of the internal combustion engine is substoichiometric, as a result, the exhaust gas catalytic converter generates NH3, and the detection and evaluation of the first and second measurement signals for diagnosing the gasoline particulate filter are NH3 is only initiated when the exhaust gas flows out of the catalytic converter. Exhaust gas catalytic converters are designed to combine and reduce pollutants from exhaust gases. When an internal combustion engine operates substoichiometrically, fuel residues (HC hydrocarbons) that could not be combusted due to lack of oxygen remain in the exhaust gas. These residues reach the exhaust gas catalytic converter and are converted there together with the pollutants. During the conversion of these pollutants and hydrocarbons in the exhaust gas catalytic converter, NH3 is produced, which in turn reacts with the oxygen stored in the exhaust gas catalytic converter inside the exhaust gas catalytic converter to form nitrogen and water. . If stored oxygen is supplied and NH3 is continuously generated due to conversion of pollutants in the exhaust gas catalytic converter, NH3 flows out from the exhaust gas catalytic converter. NH3 flowing out from the exhaust gas catalytic converter may be detected by the first NOx-/NH3- sensor, whereby the first measurement signal and the second measurement signal for diagnosing the gasoline particulate filter according to the present embodiment Detection and evaluation are initiated. According to this embodiment, the stoichiometric operation of the internal combustion engine produces NH3 as intended in the exhaust gas catalytic converter, whereby the method for diagnosing a coated gasoline particulate filter may be performed as intended. there is. Thereby, the method can be carried out at a predefined operating point of the internal combustion engine, whereby a diagnosis of the coated gasoline particulate filter can additionally be carried out preferably and accurately.

According to an embodiment, the effluent of NH3 from the exhaust gas catalytic converter is monitored using a first NOx-/NH3-sensor and detection of a first and a second measurement signal for diagnosing a coated gasoline particulate filter. and evaluation is initiated only when an increase in the NH3- concentration is detected in the first measurement signal of the first NOx-/NH3-sensor. According to this embodiment, NH3 slip or NH3 penetration through the exhaust gas catalytic converter can be detected in a reliable type and manner, and such NH3 slip or NH3 penetration can trigger the detection and evaluation of the measurement signal. . According to this embodiment, this method can be carried out as intended in the case where an essential increase in the NH 3 - concentration in the exhaust gas is present downstream of the exhaust gas catalytic converter.

According to one embodiment, the exhaust gas pipe of the internal combustion engine has a lambda sensor arranged upstream of the exhaust gas catalytic converter and designed to detect the concentration of oxygen in the exhaust gas, whereby the substoichiometric of the internal combustion engine is provided. Operation can be detected/monitored, whereby detection and evaluation of the first and second measurement signals can be prepared for diagnosing the coated gasoline particulate filter. Accordingly, with reference to the signal of the lambda sensor upstream of the exhaust gas catalytic converter, it can be detected whether the internal combustion engine is operating stoichiometrically, substoichiometrically or overstoichiometrically. If, with reference to the signal from the lambda sensor, it is recognized that the internal combustion engine is operating substoichiometrically for a predetermined period, it can be concluded that NH3 is produced within the exhaust gas catalytic converter, and that oxygen within the exhaust gas catalytic converter As far as consumed, NH3 exits the exhaust gas catalytic converter and enters the coated gasoline particulate filter. Therefore, according to this embodiment, a method for diagnosing a coated gasoline particulate filter can be prepared if the signal of the lambda sensor permits this.

According to an embodiment, the first NOx-/NH3-sensor and/or the second NOx-/NH3-sensor is a NOx-sensor.

With reference to the signal of the NOx-sensor, conclusions can be drawn about the concentration of NH3, consequently the NH3-concentration upstream and/or downstream of the gasoline particulate filter coated by the pre-installed NOx-sensor depending on the situation. can be detected or determined. The NOx-sensor upstream or downstream of the coated gasoline particulate filter can already be installed in a conventional exhaust pipe, in particular in the case of diesel, consequently according to this embodiment the method can be It can be carried out in the exhaust gas pipe of

According to one embodiment, the first NOx-/NH3-sensor and/or the second NOx-/NH3-sensor is an NH3-sensor. The NH3-sensor is only designed to detect the NH3-concentration at its own location, ie in this case upstream or downstream of the coated gasoline particulate filter. The NH3-sensor thus supplies the concentration of NH3/ammonia directly, directly and preferably in the correct type and manner, in its own arrangement position, in this case upstream or downstream of the coated particulate filter.

According to another aspect of the present disclosure, there is proposed an apparatus for diagnosing a coated gasoline particulate filter in an exhaust gas pipe of an internal combustion engine, wherein the exhaust gas pipe comprises a coated gasoline particulate filter, downstream of the gasoline particulate filter in a flow direction. a first NOx-/NH3-sensor arranged in the flow direction, and a second NOx-/NH3-sensor arranged downstream of the coated gasoline particulate filter in the flow direction, a control unit designed to control one of the methods described above. . The device can be, for example, a control unit for controlling/regulating an internal combustion engine. It is also conceivable for this device to be part of the control unit or to be installed as a further control unit, for example in a vehicle equipped with an internal combustion engine.

Embodiments and improvements of the method and apparatus according to the present disclosure are shown in the respective drawings and are described in more detail with reference to the detailed description below.
In the drawing department:
1 shows a schematic diagram of an exhaust gas pipe of an internal combustion engine according to an embodiment, and
Fig. 2 shows a first diagram with a plurality of sub-diagrams according to an embodiment.

1 shows an exhaust gas pipe 100 of an internal combustion engine, in which case the exhaust gas pipe 100 includes a lambda sensor 110 , an exhaust gas catalytic converter 120 , a first NOx-/NH3- sensor 130 , and a coating and a gasoline particulate filter 140 and a second NOx-/NH3-sensor 150 . The exhaust gas catalytic converter 120 is arranged downstream of the lambda sensor 110 in the flow direction of the exhaust gas. The first NOx-/NH3- sensor 130 is arranged downstream of the exhaust gas catalytic converter 120 in the exhaust gas flow direction. A coated gasoline particulate filter 140 is arranged downstream of the first NOx-/NH3- sensor 130 in the exhaust gas flow direction. A second NOx-/NH3-sensor 150 is arranged downstream of the gasoline particulate filter 140 in the exhaust gas flow direction. The lambda sensor 110 is designed to detect the oxygen content of the exhaust gas upstream of the exhaust gas catalytic converter 120 . The exhaust gas catalytic converter 120 is designed to convert and reduce pollutants, in particular hydrocarbons, carbon monoxide and nitrogen oxides, from exhaust gases. The first NOx-/NH3- sensor 130 is designed to detect a measurement signal characterizing the NH3-concentration downstream of the exhaust gas catalytic converter 120 and upstream of the coated gasoline particulate filter 140 . The coated gasoline particulate filter 140 is designed to filter particulates from the exhaust gas and further convert and reduce pollutants, particularly hydrocarbons, carbon monoxide and nitrogen oxides, from the exhaust gas using the coating. The second NOx-/NH3-sensor 150 is designed to detect a measurement signal characterizing the NH3-concentration of the exhaust gas downstream of the coated gasoline particulate filter 140 . 1, the lambda sensor 110, the first NOx-/NH3-sensor 130, the second NOx-/NH3-sensor 150, and in some cases, are designed to process measurement signals of another sensor A control unit 200 is further shown. In addition, the control unit 200 is configured to carry out a method or diagnosis of the coated gasoline particulate filter 140 and, if necessary, to perform a fault registration in a fault memory and further optionally with a damaged gasoline particulate filter 140 and It is designed to output the relevant error to the user of the internal combustion engine.

2 shows a diagram 300 having a plurality of sub-diagrams 310-350, each showing a different variable over time. The first sub-diagram 310 shows the lambda value 312 of the lambda sensor 110 over time. A second sub-diagram 320 shows the oxygen content or oxygen mass 322 in the exhaust gas catalytic converter 120 over time. A third sub-diagram 330 shows the oxygen content or oxygen mass 332 in the gasoline particulate filter 140 over time. A fourth sub-diagram 340 shows the first measurement signal 342 and thus the NH3 concentration upstream of the gasoline particulate filter 140 over time. A fifth sub-diagram 350 shows the second measurement signal 352 and thus the NH3 concentration downstream of the gasoline particulate filter 140 over time.

In the first sub-diagram 310 , it is shown that the internal combustion engine is initially operated over-stoichiometrically, then sub-stoichiometrically, thereafter again over-stoichiometric, and then over-stoichiometric. , and such a situation can be known by referring to the lambda value 312 . The stoichiometric operation is indicated by the dashed line 314 in the first sub-diagram 310 . A stoichiometric operation was ensured for lambda = 1, ie when there were enough fuel and oxygen fractions required for complete combustion of the mixture.

In the second sub-diagram 320 , the oxygen content or oxygen mass 322 in the exhaust gas catalytic converter 120 no longer increases in spite of the over-stoichiometric operation, ie in the catalytic converter 120 . It can be seen that the maximum oxygen load has already been reached. As soon as the internal combustion engine is operated substoichiometrically, oxygen in the exhaust gas catalytic converter 120 is not introduced into the exhaust gas catalytic converter 120 due to the reduction of NH3 to nitrogen and water and no additional oxygen is introduced into the exhaust gas catalytic converter 120 by the exhaust gas. The mass 322 will fall. It can then be seen in the second sub-diagram 320 that the oxygen content or oxygen mass 322 has reached a minimum value as soon as there is no longer oxygen present in the exhaust gas catalytic converter 120 . As soon as the internal combustion engine is again operated over-stoichiometrically, ie as soon as there is additional oxygen in the exhaust gas and thus is supplied to the exhaust gas catalytic converter 120 , the oxygen content or oxygen mass in the exhaust gas catalytic converter 120 . (322) increases again, because oxygen is newly stored again. As soon as the internal combustion engine is stoichiometrically operated again, the oxygen content or oxygen mass 322 remains constant. In other words, no new oxygen is stored because there is no oxygen to be provided in the exhaust gas, but no oxygen is required for the reduction of NH3 as NH3 does not need to be reduced.

In a third sub-diagram 330 , the oxygen content or oxygen mass 332 in the coated gasoline particulate filter 140 (GPF) is shown over time. In this sub-diagram, the oxygen content or oxygen mass 332 is initially constant at a high level from the point in which there is no longer oxygen in the exhaust gas catalytic converter until the oxygen content or oxygen mass 332 decreases as well. It can be seen that it remains This situation occurs as NH3 is drawn into the exhaust gas by the exhaust gas catalytic converter 120 and thereby reaches the coated gasoline particulate filter 140 . The NH3 is reduced in the coated gasoline particulate filter as long as oxygen is present in the coated gasoline particulate filter 140 . From the point in time when oxygen is no longer present in the gasoline particulate filter 140 , the reduction of NH3 is also no longer made, and the oxygen content or oxygen mass 332 reaches its minimum value in the gasoline particulate filter 140 . will do

A fourth sub-diagram 340 shows the first measurement signal 342 and thus the NH 3 concentration downstream of the exhaust gas catalytic converter 120 and upstream of the coated gasoline particulate filter 140 . It can be seen from the fourth sub-diagram 340 that, until the point at which oxygen is no longer present in the exhaust gas catalytic converter 120 for reduction of NH3, the NH3 concentration downstream of the exhaust gas catalytic converter 120 is zero or NH3 It can be seen that there is no As soon as there is no longer oxygen present in the exhaust gas catalytic converter 120 , NH3 penetration occurs accordingly, which leads to an increase in the NH3 concentration downstream of the exhaust gas catalytic converter 120 . Such a situation can be seen from the first measurement signal 342 in the fourth sub-diagram 340 . As soon as oxygen is supplied to the exhaust gas catalytic converter 120 again, the concentration of NH3 downstream of the exhaust gas catalytic converter 120 finally drops again, whereby NH3 can be reduced again.

A fifth sub-diagram 350 shows two second measurement signals 352 over time, so that these measurement signals are NH3 downstream of the gasoline particulate filter 140 in different states of the gasoline particulate filter 140 . - Show the concentration. A second measurement signal 352a shown in the fifth sub-diagram 350 shows a damaged coated gasoline particulate filter 140 . The second measurement signal 352b shown in the fifth sub-diagram 350 shows the measurement signal at the gasoline particulate filter 140 that is intact and can function. The NH3 concentration downstream of the gasoline particulate filter 140 in the damaged gasoline particulate filter 140 almost simultaneously follows the NH3 concentration upstream of the gasoline particulate filter 140 . Accordingly, it can be seen here that NH3 flows through the gasoline particulate filter 140 in an unconverted state. Thereby, the gasoline particulate filter 140 has cracks, for example, so that NH3 can flow through unimpeded as a result. Accordingly, with reference to the first measurement signal 342 and the second measurement signal 352 , damage to the gasoline particulate filter 140 can be identified. The undamaged gasoline particulate filter 140 in the presence of oxygen converts NH3 so that NH3 is not initially discharged from the gasoline particulate filter 140 as a result. Only as soon as there is no longer oxygen in the gasoline particulate filter 140 , NH3 is discharged from the undamaged gasoline particulate filter 140 and consequently thereafter the NH3 concentration downstream of the gasoline particulate filter 140 . will also increase. However, this increase is made in a time-offset state. This time offset can be found in the fifth subdiagram 350 using the shown second measurement signal 352b which increases only as soon as there is no longer oxygen in the gasoline particulate filter 140 to convert NH3. is shown (see third subdiagram 330). Accordingly, a conclusion is drawn for the coated gasoline particulate filter 140 that may function if the increase in the second measurement signal 352b is time offset with respect to the increase in the first measurement signal 342 . can be taken down

Claims (9)

A method for diagnosing a gasoline particulate filter (140) of an exhaust gas pipe (100) of an internal combustion engine, comprising:
The exhaust gas pipe 100 includes a coated gasoline particulate filter 140 , a first NOx-/NH3- sensor 130 arranged upstream of the gasoline particulate filter 140 in an exhaust gas flow direction, and an exhaust gas flow direction. and a second NOx-/NH3-sensor (150) arranged downstream of the gasoline particulate filter (140), the method comprising:
- operating the internal combustion engine, the exhaust gas flowing through the exhaust gas pipe (100);
- detecting a first measurement signal (342) with a first NOx-/NH3-sensor (130) characterizing the NH3-concentration in the exhaust gas upstream of the gasoline particulate filter (140);
- detecting a second measurement signal (352) with a second NOx-/NH3-sensor (150) characterizing the NH3-concentration in the exhaust gas downstream of the gasoline particulate filter (140); and
- evaluating the first measurement signal 342 and the second measurement signal 352 for diagnosing the coated gasoline particulate filter 140 .
A method for diagnosing a gasoline particulate filter in an exhaust gas pipe of an internal combustion engine, comprising: 2. The method of claim 1, wherein the first measurement signal (342) is compared with the second measurement signal (352) for evaluation, and NH3 in the first measurement signal (342) and in the second measurement signal (352) - A method for diagnosing a gasoline particulate filter in an exhaust gas pipe of an internal combustion engine, recognizing that the coated gasoline particulate filter 140 is damaged if an increase in concentration is detected almost simultaneously. 3. The coated gasoline particulate filter (140) according to claim 1 or 2, wherein the coated gasoline particulate filter (140) is capable of storing oxygen used for the conversion of NH3, the method only providing a predetermined amount of the coated gasoline particulate filter (140) in the coated gasoline particulate filter (140). A method for diagnosing a gasoline particulate filter in an exhaust gas pipe of an internal combustion engine, which is carried out only in the presence of oxygen. 4. The exhaust gas catalytic converter (120) according to any one of the preceding claims, wherein the exhaust gas pipe (100) of the internal combustion engine is arranged upstream of the first NOx-/NH3- sensor (130). As a result, the exhaust gas first flows through the exhaust gas catalytic converter 120, and in this case, the operation of the internal combustion engine is substoichiometric, and consequently, the exhaust gas catalytic converter 120 generates NH3 The detection and evaluation of the first measurement signal 342 and the second measurement signal 352 for diagnosing the gasoline particulate filter 140 are started only when NH3 flows out of the exhaust gas catalytic converter 120. , a method for diagnosing a gasoline particulate filter in an exhaust gas pipe of an internal combustion engine. 5. The method of claim 4, wherein the outflow of NH3 from the exhaust gas catalytic converter (120) is monitored using a first NOx-/NH3-sensor (130) and a first for diagnosing a coated gasoline particulate filter (140). The detection and evaluation of the first measurement signal 342 and the second measurement signal 352 only occur when an increase in the NH3- concentration is detected in the first measurement signal 342 of the first NOx-/NH3- sensor 130 . Disclosed is a method for diagnosing a gasoline particulate filter in an exhaust pipe of an internal combustion engine. 6. A lambda sensor (110) according to claim 4 or 5, wherein the exhaust gas pipe (100) of the internal combustion engine is arranged upstream of the exhaust gas catalytic converter (120) and is designed to detect the oxygen concentration in the exhaust gas. a gasoline particulate filter coated with the detection and evaluation of the first measurement signal 342 and the second measurement signal 352 by means of which substoichiometric operation of the internal combustion engine can be detected; 140), a method for diagnosing a gasoline particulate filter in an exhaust gas pipe of an internal combustion engine. The method according to any one of the preceding claims, wherein the first NOx-/NH3-sensor (130) and/or the second NOx-/NH3-sensor (150) is a NOx-sensor. 7. An internal combustion engine according to any one of the preceding claims, wherein the first NOx-/NH3-sensor (130) and/or the second NOx-/NH3-sensor (150) is an NH3-sensor. A method for diagnosing a gasoline particulate filter in an exhaust gas pipe. An apparatus for diagnosing a gasoline particulate filter (140) of an exhaust gas pipe (100) of an internal combustion engine, comprising:
The exhaust gas pipe 100 includes a coated gasoline particulate filter 140 , a first NOx-/NH3- sensor 130 arranged upstream of the gasoline particulate filter 140 in the exhaust gas flow direction, and an exhaust gas flow direction. A second NOx-/NH3-sensor (150) arranged downstream of the coated gasoline particulate filter (140), has a control unit (200) designed to control the method according to any one of claims 1 to 8 A device for diagnosing a gasoline particulate filter (140) of an exhaust gas pipe of an internal combustion engine.

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