• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    SUMMARY The invention relates to a process in a process in an exhaust gas purification system comprising a DOC unit (260) arranged downstream of an internal combustion engine (231), comprising the steps of: - determining a first NOR content of exhaust gases upstream of said DOC unit; - determining a second NOR content of the exhaust gases downstream of said DOC unit; - start up and fuel the said DOC unit; - diagnosing said DOC unit (260) on the basis of said first NOR content and said second NOR content during a relatively small supply of fuel per unit time for the DOC unit (260). The invention also relates to a computer program product comprising program code (P) for a computer (200; 210) for implementing a method according to the invention. The invention also relates to a device in an exhaust gas purification system and a motor vehicle (100) equipped with the device.
    公开号:SE1450080A1
    申请号:SE1450080
    申请日:2014-01-29
    公开日:2015-07-30
    发明作者:Ola Stenlåås；Mikael Lundström
    申请人:Scania Cv Ab；
    IPC主号:
    专利说明:

    TECHNICAL FIELD The present invention relates to a method of an exhaust gas purification system. The invention also relates to a computer program product comprising program code for a computer to implement a method according to the invention. The invention also relates to a device in an exhaust gas purification system and a motor vehicle which is equipped with the device.
    BACKGROUND Exhaust gas cleaning systems of today's motor vehicles include a number of different components. For example, an exhaust gas purification system may include a DOC unit (Diesel Oxidation Catalyst) arranged in a passage downstream of an internal combustion engine has the vehicle.
    Other components that may be arranged downstream of said engine are a DPF unit (Diesel Particulate Filter) and a SCR catalyst (Selective Catalytic Reduction).
    For many reasons, it is inconvenient to be able to diagnose individual components of exhaust gas cleaning systems, such as trucks and buses. Diagnosis of components has exhaust gas purification systems has motor vehicles can, for example, be difficult to determine radiating performance and / or function has the various components. Diagnosis of individual components in exhaust gas cleaning systems can in some states be subject to laws, regulations or directives, which of course vehicle manufacturers must comply with, not least from an environmental and competition perspective.
    Diagnosis of the said DOC unit is today problematic, in particular there are engines that do not have an external fuel injector and whose fuel injection concept does not allow mail injection. ldag 'With known diagnostic procedures for DOC units, it is black or impossible to determine whether the DOC unit is defective, in case the DOC unit shows only.
    US 20100319316 describes a system and a method for diagnosing an oxidation catalyst.
    JP 2012036856 describes a device for diagnosing a catalyst.
    SUMMARY OF THE INVENTION Thus, there is a need to reliably and industry-efficiently diagnose a DOC unit having an exhaust purification system having a motor vehicle.
    There is a need to diagnose a DOC unit in an efficient, reliable and user-friendly way in terms of performance.
    An object of the present invention is to provide a new and advantageous method in an exhaust gas purification system.
    Another object of the invention is to provide a new and advantageous device in an exhaust gas purification system and a new and advantageous computer program in an exhaust gas purification system.
    A further object of the invention is to provide an alternative method in an exhaust gas cleaning system, an alternative device in an exhaust gas cleaning system and an alternative computer program in an exhaust gas cleaning system having a motor vehicle.
    A further object of the invention is to provide a method of an exhaust gas purification system, an apparatus of an exhaust gas purification system and a computer program 3 for achieving a reliable diagnosis of a DOC unit of a motor vehicle.
    A further object of the invention is to provide a method of an exhaust gas purification system, an apparatus of an exhaust gas purification system and a computer program for achieving a reliable diagnosis of a DOC unit of an SCR system having a motor vehicle.
    Some of said objects are achieved with a method of an exhaust gas purification system according to claim 1. Other objects are achieved with a device of an exhaust gas purification system according to claim 6. Advantageous embodiments are stated in the dependent claims.
    According to one aspect of the present invention, there is provided a method of an exhaust gas purification system comprising a DOC unit disposed downstream of an internal combustion engine, comprising the steps of: determining a first NOR content of exhaust gases upstream of said DOC unit; - determining a second NOR content of the exhaust gases downstream of said DOC unit; - start up and fuel the said DOC unit; and - diagnosing said DOC unit on the basis of said first NOR content and said second NOR content during a relatively small supply of fuel for the DOC unit per season.
    This provides a reliable and industry-efficient method for diagnosing a DOC unit having a finishing system having a motor vehicle.
    By utilizing a probability against fuel, for example diesel, has the NOR sensors, a reliable and robust procedure can be used to diagnose a DOC unit has a finishing system has a motor vehicle achieved.
    According to one aspect of the invention, said DOC unit is started up before said first NOR content and said second NOR content are determined. The DOC unit is activated when its temperature reaches a tooth temperature. If the DOC unit is start-up audit active, it will achieve combustion of all supplied fuel. This is provided that the industry is not significantly overdosed on the said DOC unit. According to one aspect of the invention, it is determined whether at least a flag of the following phenomena occurs: - lowering of the level of continuously detected NON content of said first NOx sensor; high frequency oscillation has detected NON content of said first NON sensor; and - error signaling has the said first NOR sensor.
    According to one aspect of the invention, it is determined whether at least a flag of the following phenomena appears when the DOC unit is active: - lowering of the level has continuously detected NON content of said second NON sensor; increase in level has continuously detected NON content of only said second NOR sensor; high frequency oscillation has detected NON content of said second NON sensor; and - error signaling has said second NON sensor.
    If at least a flag of these phenomena appears, said second NOR sensor, which is arranged downstream of said DOC unit, it can be determined that said DOC unit does not function as intended. In this case, diagnosis may indicate that the said DOC unit does not show satisfactory performance. If these phenomena are present at low industry dosage to said DOC unit when it is active, diagnosis of said DOC unit can advantageously be achieved.
    A measure of radiating performance, including any degradation of normal or satisfactory performance, can be determined on the basis of at least a flag of: - a relative measure of said decrease in level has continuously detected NON content of said second NON sensor; a magnitude of said high frequency oscillation has detected NOR content of said second NON sensor; and - intensity and / or frequency and / or information content in said error signaling has said second NON sensor.
    Said first NO, content of exhaust gases upstream of said DOC unit can be determined continuously. Said second NO 2 content has exhaust gases downstream of said DOC unit can be determined continuously.
    The method may further comprise the step of: - following changes in said first NO, content and said second NO, content during a period of said low fuel supply, wherein changes in the form of a decrease in fixed NO, content and / or high frequency oscillation at said first NO, content and said second NO, content are taken as an indication of fuel hazard occurrence in said exhaust gases.
    The method may comprise the step of: - following changes in said first NO, content and / or said second NO, content during a period of said low fuel supply, wherein changes in the form of a decrease in fixed NO 2 content and / or high frequency oscillation has the said first NO, content and / or the said second NO, content is taken as an indication of the occurrence of fuel in the said exhaust gases.
    The procedure may further comprise the step of: - following changes in said first NO 'content during a period of said low fuel supply, changes in the form of a reduction in fixed NO' content being taken as an indication of fuel occurrence in said exhaust gases.
    The process may further comprise the step of: - following changes in said first NO, content during a period of said low fuel supply, changes in the form of a decrease in fixed NO 'content and high frequency oscillation of said first NO, content being taken as indication of industry occurrence in the said exhaust gases.
    In this case, it can be advantageously established that fuel is actually present mixed with 30 exhaust gases from said engine having said exhaust gas purification system.
    The process may further comprise the step of: - comparing changes having said first NO, content and said other NO, content, a deficient function having said DOC unit is taken as the conclusion of 6 industry occurrences in said exhaust gases are found by means of similar changes in said first NOR content and the said other NOR content.
    The procedure may comprise the step of: - comparing changes having said first NOR content and said second NOR content, a deficient function having said DOC unit being taken as the conclusion of industry occurrence in said exhaust gases is found in a fixed reduction has said first NOR content and a fixed increase of only said second NOR content.
    The said similar changes may include a reduction of the said first NOR content and the said second NOR content, respectively. Said respective depressions may be temporary depressions relative to a measured NOR content where fuel is not supplied to the exhaust gases from said engine.
    Said similar changes may include high frequency oscillation having said first NOR content and said second NOR content, respectively. The said high-frequency oscillation can alternatively be called a ripple.
    The method may further comprise the step of: - taking the malfunction has the DOC unit which is concluded in the event of a signal regarding malfunction due to fuel occurrence in said exhaust gases in connection with the feeding of said first NOR content and the feeding of said second NOR content.
    When the said NOR sensors are exposed to industry, these can be temporarily, or permanently, negatively affected. In this case, a lack of food function can cause the sensors to arise. In order to inform a control unit, the exhaust gas purification system called the NOR sensors has been arranged to generate an error signal indicating that the sensor At is negatively affected and therefore may not be reliable. According to the inventive method, such signals can be used to indicate the presence of fuel, and in this case also have the said 000 unit.
    The method may comprise the step of: 7 - ceasing a supply of reducing agent to said exhaust gases in order to improve the determination of a process having said second NOR content.
    According to one aspect of the present invention, there is provided an apparatus in an exhaust gas purification system comprising a DOC unit disposed downstream of an internal combustion engine, comprising: means adapted to determine a first NON content of exhaust gases upstream of said DOC unit, and means adapted to establish a other NOR contents have exhaust gases downstream of said DOC unit; means adapted to start up said DOC unit; and - means adapted to supply fuel to said DOC unit; means adapted to diagnose said DOC unit on the basis of said first NON content and said second NON content during a relatively small supply of fuel per unit of time for the DOC unit.
    According to one aspect of the present invention, there is provided an apparatus in an exhaust gas purification system comprising a DOC unit disposed downstream of an internal combustion engine, comprising: means adapted to determine a first NOR content of the exhaust gases upstream of said DOC unit; means adapted to determine a second NOR content of the exhaust gases downstream of said DOC hot; means adapted to supply fuel to said DOC unit; means adapted to, when said DOC unit is activated, diagnose said DOC unit on the basis of said first NOR content and said second NOR content during a relatively small supply of fuel per unit of time for the DOC unit.
    The device may comprise: - means adapted to follow changes having said first NOR content and said second NOR content during a period of said low fuel supply; whereby changes in the form of a decrease in the fixed NOR content and / or high-frequency oscillation have the said first NOR content and the said second NOR content is taken as an indication of industry occurrence in the said exhaust gases. The device may comprise: - means adapted to follow changes in said first NO, content and said second NO, content during a period of said low fuel supply; wherein changes in the form of a decrease in the fixed NO, content of said first NO, content and an increase of only the said second NO, content are taken as an indication of the occurrence of fuel in said exhaust gases.
    The device may comprise: - means adapted to follow changes in said first NO, content and / or said second NO, content during a period of said low fuel supply, wherein changes in the form of a reduction of fixed NO, content and / or high-frequency oscillation of said first NO, content and / or said second NO, content is taken as an indication of the occurrence of fuel in said exhaust gases.
    The device may comprise: - means adapted to follow changes in said first NO, content and said second NO, content during a period of said low fuel supply; means adapted to determine the fuel presence in said exhaust gases in determining changes in the form of a decrease in the determined NO, content and / or high-frequency oscillation of said first NO, content and said second NO, content.
    The device may comprise: - means adapted to follow changes in said first NO, content and said second NO, content during a period of said low fuel supply; means adapted to determine the occurrence of industry in said exhaust gases when determining changes in the form of a reduction of said first NO 'content and an increase of only said second NO' content.
    The device may comprise: - means adapted to compare changes in said first NO, content and said second NO, content, whereby a lack of function of said DOC unit is taken as a conclusion of the fuel presence in said exhaust gases is found by means of similar changes in said first NO 2 content and the said other NO 2 content. The device may comprise: - means adapted to compare changes in said first NOR content and said second NOR content; means adapted to determine a deficient function of said DOC unit as the fuel presence in said exhaust gases is determined by means of similar changes in said first NOR content and said second NOR content.
    The device may comprise: - means adapted to take a malfunction of the DOC unit which is concluded in the event of a signal regarding malfunction due to fuel occurrence in said exhaust gases in connection with the feeding of said first NOR content and the feeding of said second NOR content.
    The device may comprise: - means adapted to cease with a supply of reducing agent to said exhaust gases in order to improve the determination of a course of said second NOR content.
    The device may comprise: - means adapted to vary the supply of reducing agent to said exhaust gases in order to improve the determination of a course of said second NOR content.
    According to one aspect of the present invention, there is provided a motor vehicle comprising a device in an exhaust gas purification system according to any one of claims 6-10.
    Said motor vehicle can be anything from a truck, bus or car.
    According to one aspect of the present invention, computer programs are provided in an exhaust gas purification system, said computer program comprising program code for causing an electronic control unit or another computer connected to the electronic control unit to perform the steps of any of claims 1-5.
    According to one aspect of the present invention, computer programs are provided in an exhaust gas purification system, wherein said computer program includes program code for causing an electronic control unit or another computer connected to the electronic control unit to perform the steps of any of claims 1-5, when said program code crosses said control unit or said computer.
    According to one aspect of the present invention, computer programs are provided in an exhaust gas purification system, wherein said computer program comprises program code stored on a computer readable medium for causing an electronic control unit or another computer connected to the electronic control unit to perform the steps of any of claims 1. -5.
    According to one aspect of the present invention, computer programs are provided in an exhaust gas purification system, said computer program comprising program code stored on a computer readable medium for causing an electronic control unit or another computer connected to the electronic control unit to perform the steps of any of claims 1. -5, when said program code is crossed at said control unit or said computer.
    According to one aspect of the present invention, there is provided a computer program product comprising a program code stored on a computer readable medium for performing the method steps of any of claims 1-5, when said computer program is crossed on an electronic control unit or another computer connected to the electronic the control unit.
    According to one aspect of the present invention, there is provided a computer program product comprising a program code non-volatilely stored on a computer readable medium for performing the process steps of any of claims 1-5, when said program code is crossed on an electronic control unit or another computer connected to the electronic control unit.
    Additional objects, advantages and novel features of the present invention will become apparent to those skilled in the art from the following details, as well as through reference to the invention. While the invention is described below, it should be understood that the invention is not limited to the specific details described. Those skilled in the art having access to the laroma hari will recognize additional applications, modifications and incorporations within other fields which are within the scope of the invention.
    SUMMARY DESCRIPTION OF THE DRAWINGS For a more complete understanding of the present invention and further objects and advantages thereof, reference is now made to the following detailed description which is to be read in conjunction with the accompanying drawings in which like reference numerals refer to like parts in the various figures, and in which: 1 schematically illustrates a vehicle, according to an embodiment of the invention; Figure 2a schematically illustrates a subsystem of the vehicle shown in Figure 1, according to an embodiment of the invention; Figure 2b schematically illustrates a subsystem of the vehicle shown in Figure 1, according to an embodiment of the invention; Figure 3a schematically illustrates a diagram according to an embodiment of the invention; Figure 3b schematically illustrates a diagram, according to an embodiment of the invention; Figure 3c schematically illustrates a diagram, according to an embodiment of the invention; Figure 4a schematically illustrates a flow chart of a process, according to an embodiment of the invention; Figure 4b schematically illustrates in further detail a flow chart of a method, according to an embodiment of the invention; and Figure 5 schematically illustrates a computer, according to an embodiment of the invention.
    DETAILED DESCRIPTION OF THE FIGURES Referring to Figure 1, a side view of a vehicle 100 is shown. The exemplary vehicle 100 consists of a tractor 110 and a trailer 112. The vehicle may be a heavy vehicle, such as a truck or a bus. The vehicle can alternatively be a 30 passenger car.
    The term "lank" 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 line. 12 Hari refers to the term "reductant" as a means used to react with certain emissions in an SCR system. These emissions can e.g. be NOR gas. Said reductant is according to an embodiment so-called AdBlue. Of course, other kinds of reductants can be used. Here, AdBlue is mentioned as an example of a reductant, but a person skilled in the art realizes that the inventive process and the inventive SCR system can be realized with other types of reductants, with the necessary adaptations, such as e.g. adaptations to adequate freezing point for selected reductants, in control algorithms kir to execute program code in accordance with the inventive method.
    According to one example, the term "small fuel supply" may be in the order of 0.1-1.0 grams per second. It was necessary to call for fuel supply per unit of time, which refers to one industry supply per unit of time that is significantly lower than during normal / normal / normal operation. This operation includes fuel supply according to stored drivers has a control unit to control fuel supply.
    It should be noted that the invention is suitable for application having a suitable exhaust gas purification system comprising a DOC unit, and is not limited to an exhaust purification system comprising an SCR system having a motor vehicle. The inventive method and the inventive device are suitable for other platforms which include an exhaust gas purification system of motor vehicles, such as e.g. watercraft. The watercraft can be of any kind, such as e.g. motor boats, ships, ferries or ships.
    The inventive method and the inventive device in an exhaust gas purification system according to an aspect of the invention are also suitable for e.g. systems including tractors, dumpers, power tools, industrial engines and / or powered industrial robots.
    The inventive method and the inventive device in an exhaust gas purification system according to an aspect of the invention also illuminate choices for different types of power plants, such as e.g. an electric power plant comprising a diesel generator. The inventive method and the inventive device of an exhaust gas purification system make choices for an arbitrary engine system including an engine and an SCR system, such as e.g. at a locomotive or other platform.
    The inventive method and the inventive device of an exhaust gas purification system make choices for a system which includes a NON generator, for example a diesel engine, the exhaust gases of which are to be purified.
    The inventive method and inventive device of an exhaust gas purification system makes choices for a system that includes a NOx generator, such as a diesel engine, and a DOC unit.
    In this he refers to the term "line" to a passage for holding and transporting a fluid, such as e.g. a reductant in liquid form. The pipe can be a rudder of any dimension. The cable can consist of an arbitrary, suitable material, such as e.g. plastic, rubber or metal.
    Referring to Figure 2a, a subsystem 299 is shown having the vehicle 100. The subsystem 299 may be located in the tractor 110. The subsystem 299 may form part of an SCR system incorporating the exhaust gas purification system according to an aspect of the present invention, the exhaust gas purification system being described in further detail. with male reference to Figure 2b.
    According to this example, the subsystem 299 consists of a container 205 which is arranged to hold a reductant. A first line 271 is arranged to lead the reductant to a pump 230 from the container 205. Said pump 230 is arranged to pump up the reductant from the container 205 via the first line 271 and via a second line 272 supply said reductant to a dosing unit 250. The pump 230 is arranged to pressurize the reductant in the second line 272.
    The dosing unit 250 is arranged to supply said reductant to an exhaust gas cleaning system (see Figure 2b) has the vehicle 100. More specifically, the dosing unit 250 is arranged to supply a suitable amount of reductant to an exhaust cleaning system in a controlled manner has the vehicle 100. According to this embodiment, a 14 SCR catalyst (not shown) arranged downstream of a low supply of the reductant is provided. The amount of reductant supplied to the exhaust system is intended to be used in the SCR catalyst to reduce the amount of unwanted emissions.
    A third conduit 273 is presently disposed between the metering device 250 and the container 205. The third conduit 273 is arranged to return a certain amount of the reductant fed to the metering unit 250 to the container 205.
    The first control unit 200 is arranged for communication with the pump 230 via a line 292. The first control unit 200 is arranged to control operation of the pump 230 in order to e.g. regulate the flow of the reductant within the subsystem 299.
    The first control unit 200 is arranged for communication with the dosing unit 250 via a long L250. The first control unit 200 is arranged to control the operation of the dosing unit 250 in order to e.g. regulating the supply of the reductant to the exhaust gas purification system has the vehicle 100. The first control unit 200 is arranged to activate circulation of said reducing agent by means of said pump 230 as it is judged to be suitable. The first control unit 200 is arranged to activate dosing of said reducing agent when it is judged to be appropriate.
    According to one aspect of the present invention, said first control unit is arranged to control said dosing unit 250 in such a manner that the supply of reducing agent to said exhaust gases temporarily ceases. Thus, in diagnosing said DOC unit, the exhaust gas purification system has been supplied according to one aspect of the present invention with no or substantially no reducing agent to an SCR catalyst having the exhaust purification system. In this case, the efficient diagnosis of a DOC unit has the so-called exhaust gas purification system.
    A second control unit 210 is arranged for communication with the first control unit 200 via a long L210. The second control unit 210 may be releasably connected to the first 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 inventive process steps. The second control unit 210 can be used to load Over program code to the first control unit 200, in particular program code to perform the inventive method. The second control unit 210 may alternatively be arranged for communication with the first control unit 200 via an internal network in the vehicle. The second control unit 210 may be arranged to perform substantially similar functions to the first control unit 200.
    Figure 2b schematically illustrates a subsystem 289 of the vehicle 100 shown in Figure 1, according to an embodiment of the invention. Said subsystem 289 forms part of an exhaust gas purification system of the vehicle 100. Said subsystem 299 described with reference to Figure 2a may also form part of said exhaust gas purification system.
    An engine 231 is provided, which in operation causes an exhaust gas flow which is led via a first passage 235 to a DOC unit 260. A second passage 245 is arranged to direct exhaust gases from said DOC unit 260 to a DPF unit 265. Said DPF unit 265 includes a Diesel Particulate Filter. A third passage 255 is arranged to direct exhaust gases from said DPF unit 265 to an SCR catalyst arrangement 270. A fourth passage 256 is arranged to direct exhaust gases from said SCR catalyst arrangement 270 to an environment having the vehicle 100.
    Said dosing unit 250 described with reference to Figure 2a is arranged to dose reducing agent into said third passage 255. In Figure 2b said dosing unit 250 and certain other components have the SCR system described with reference to Figure 2a in order to clear Figure 2b . It should be noted that said exhaust gas purification system does not necessarily need to include said SCR catalyst arrangement 270 and certain components have said subsystem 299, for example said metering unit 250, container 205 and pump 230.
    The first control unit 200 is arranged for communication with the motor 231 via a long L231. The first control unit 200 is arranged to control operation has the said motor 231. The first control unit 200 is for instance arranged to control the fuel metering to the combustion chamber has the said motor 231. In this case the first control unit 200 is arranged to control the fuel metering in such a way that unburned fuel can be carried. said exhaust gases to the first passage 235. In this case, the first control unit 200 is arranged to diagnose said DOC unit 260 during a relatively small supply of fuel to the DOC unit 260 to said DOC unit 260 per unit time.
    Fuel metering means 222 are arranged upstream of said DOC unit 260 and downstream of said motor 231. The first control unit 200 is arranged for communication with said fuel metering means 233 via a line L233. The first control unit 200 is arranged to control the dosing of fuel, for example diesel, into said first passage 235 by means of said industry dosing means 233.
    Thus, fuel in a controlled manner, by means of said first control unit 200, can be supplied to said DOC unit 260 from said engine 231 and / or said fuel metering means 233. According to one aspect of the present invention only a small amount of fuel is supplied to exhaust gases in said first passage 235 in diagnosing said DOC unit 260.
    A first NOR sensor 221 is arranged upstream of said DOC unit 260 at said first passage 235. Said first NOR sensor 221 is arranged for communication with the first control unit 200 via a long L221. Said first NON sensor 221 is arranged to continuously determine a radiating NOR content in the first passage 235. Said first NOR sensor 221 is arranged to continuously send signals Si including information about a radiating NOR content in said first passage 235 to the first passage 235. first control unit 200 via line L221.
    A second NOR sensor 222 is arranged downstream of said DOC unit 260 at said second passage 245. Said second NOR sensor 222 is arranged for communication with the first control unit 200 via a line L222. Said second NON sensor 222 is arranged to continuously determine a radiating NOR content in the second passage 245. Said second NON sensor 222 is arranged to continuously send signals S2 including information about a radiating NOR content in said second passage 245 to the first control unit 200 via line L222.
    Said first NON sensor 221 and said second NOR sensor 222 can be used to provide information on erasing NOR content in the first passage 235 and the second passage 245, respectively. In this case, the first control unit 200 can be arranged to control the supply of fuel in the first passage 235 in an appropriate manner on the basis of information thereon.
    According to the embodiment described with reference to the exhaust gas purification system 5 illustrated in Figure 2b, said second NOR sensor 222 is arranged in the second passage 245. It is pointed out that the second NOR sensor 222 according to an alternative embodiment may be arranged in the third passage 255, downstream of said DPF unit 265 and upstream of said SCR catalyst arrangement 270. According to an alternative embodiment, the second NOR sensor 222 may be arranged in the fourth passage 256, downstream of said SCR catalyst arrangement 270.
    According to an exemplary embodiment, said first NOR sensor 221 is arranged in the first passage 235, upstream of said DOC unit 260 and downstream of said engine 231 to continuously feed / detect / determine a first NON content of the exhaust gases there and said second NOR sensor 222 arranged downstream of said DOC unit 260, for example at the flakes of the passages 245, 255 or 256, in order to continuously feed / detect / determine a second NOR content of the exhaust gases from the engine 231.
    According to an exemplary embodiment, there may be more than one second NOR sensor 222 arranged in the exhaust gas purification system 289. In this case, the course of the said plurality of NOR sensors 222 can be taken into account according to the method according to the invention. For example, a decrease in NOR content or high frequency oscillating of respective NOR signals can be used to determine the fuel occurrence of exhaust gases downstream of said DOC unit 260, which DOC unit 260 is active and has a radiating temperature in excess of a tooth temperature Tref.
    A temperature sensor 241 is arranged upstream of said DOC unit 260 at said first passage 235. Said temperature sensor 241 is arranged for communication with the first control unit 200 via a line L241. Said temperature sensor 241 is arranged to continuously determine a radiating temperature T1meas of the exhaust gases in the first passage 235. Said temperature sensor 241 is arranged to continuously send signals ST1meas including information about a radiating temperature T1meas of the exhaust gases in said first passage 235 to the first control unit 200 lanken L241. According to one embodiment, the first control unit 200 is arranged to determine by means of a calculation model stored therein a radiating temperature T1cal of the exhaust gases in the first passage 235. Said radiating temperature T1cal has the exhaust gases in the first passage 235 can be determined on the basis of e.g. a fixed exhaust mass flow and a matte on to the engine 230 dosed amount of fuel. Thus, the said radiating temperature T1cal can be calculated / modeled / estimated in an appropriate manner by means of the said first control unit 200.
    A sensor (not shown) for supplying a radiating exhaust mass flow MF may be provided in the first passage 235. The said exhaust mass flow sensor is arranged to continuously determine a radiating exhaust mass flow MF in the first passage 235 and send signals including the information therefor to the control unit 200. via a dedicated link (not shown).
    According to one embodiment, the first control unit 200 is arranged to determine by means of a calculation model stored therein a radiating exhaust mass flow MF in the first passage 235. Said radiating exhaust mass flow MF in the first passage 235 can be determined on the basis of e.g. a fixed operating state has the motor 231.
    The first control unit 200 is arranged to continuously estimate by means of a stored model a radiating temperature Tmod has DOC unit 260. The first control unit 200 is arranged to calculate by means of said calculation model a radiating temperature Tmod has DOC unit 260 on the basis of said fixed temperature has the exhaust gases Tlmeas and / or Ti cal in the first passage 235. According to an example, the first control unit 200 is arranged to calculate by means of said model a radiating temperature Tmod has the DOC unit 260 on the basis of a metered amount of fuel in the first passage 235, said fixed temperature Tlmeas and / or Ti cal has the exhaust gases in the first passage 235 and a radiating exhaust mass flow MF in the first passage 235.
    According to an exemplary embodiment, a temperature sensor is provided which is arranged to supply a radiating temperature having the DOC unit 260. The first control unit 200 is arranged to determine whether the said DOC unit 260 is activated / started / toothed or not. The first control unit 200 may then be arranged to determine if a measured / detected / calculated / determined temperature of the DOC unit 260 exceeds a certain tooth temperature of the DOC unit 260.
    Said tooth temperature can also be called activation temperature. Since the first control unit 200 has determined that the DOC unit 260 is active, the inventive procedure can be performed.
    According to one embodiment, the first control unit 200 is arranged to determine an initial NOR content of exhaust gases upstream of said DOC unit 260. According to one embodiment, the first control unit 200 is arranged to determine an exhaust gas content of a second NOR content downstream of said DOC unit 260. .
    According to one embodiment, the first control unit 200 is arranged to start up said DOC unit. In this case, the first control unit is arranged to control the operation of the engine and / or supply fuel to said DOC unit 260 by means of said industry dosing means 233 in order to effect a temperature increase in the exhaust gas purification system whereby the DOC unit can be activated / started / started.
    The first control unit 200 is according to one embodiment arranged to control the supply of fuel to the said DOC unit 260. The first control unit 200 is according to one embodiment arranged to diagnose the said DOC unit 260 on the basis of said first NOR content and said second NOR content during a relatively small industry supply per unit time for the DOC unit 260.
    According to one embodiment, the first control unit 200 is arranged to follow changes having said first NOR content and said second NOR content during a period of said small fuel supply, whereby changes in the form of a decrease in fixed NOR content and high frequency oscillation have said NOR content and the said other NOR content are taken as an indication of industry occurrence in the said exhaust gases.
    According to one embodiment, the first control unit 200 is arranged to compare changes having said first NOR content and said second NOR content, a deficient function having said DOC unit 260 being taken as a conclusion of industry occurrence in said exhaust gases is found by means of similar changes in said first NOR content and the said other NOR content.
    According to an embodiment, the first control unit 200 is arranged to take a malfunction having the DOC unit 260 which is concluded in the event of a signal regarding malfunction due to fuel occurrence in said exhaust gases in connection with the feeding of said first NOR content and the feeding of said second NOR content.
    When exposed to industry, said first NOR sensor 221 and said second NOR sensor 222 can be affected in such a way that they generate an error signal and send it to the first control unit 200. Said error signal may indicate that the sensor is negatively affected and may be incorrect. varden. The first control unit 200 is arranged to diagnose said DOC unit on the basis of said error signal indicating lack of food function until 1614 of fuel occurrence in said exhaust gases in connection with the feeding of said first NOR content and the feeding of said second NOR content.
    According to one embodiment, the first control unit 200 is arranged to cease with a supply of reducing agent to said exhaust gases in order to improve the determination of a process having said second NOR content. This is particularly useful in the case where the second NOR sensor 222 is presently arranged downstream of the SCR catalyst arrangement 270.
    Presentation means 220 are arranged for communication with said first control unit 200 via a long L220. The first control unit 200 is arranged to present a result of said diagnosis of said DOC unit 260. Said result may, for example, indicate "satisfactory function" or "defective". For example, a degree of disability may have the named DOC unit presented, this degree of disability can be stated in percent. Said presentation means 2 may include loudspeakers for reproducing synthesized rust or other audible feedback. Said display means 220 may include a display screen, for example a so-called touch screen for visual feedback of the said result. Figure 3a schematically illustrates a diagram according to an embodiment of the invention. This illustrates how a NOR sensor, for example the first NOR sensor 221 and the second NOR sensor 222, is affected by the occurrence of exhaust gases in the exhaust gas purification system 289. The NOR sensors 221, 222 can be affected in such a way that their output signals are occasionally includes a high frequency oscillating signal, as shown in Figure 3a.
    During a time period T1 to T2, a small amount of fuel is supplied to the said DOC unit 260, while this is activated. In this case, the said NOR sensors exposed to industry exhibit the said high-frequency oscillation, also called the "ripple".
    RV cases where both the first No-sensor 221 and the second NOR sensor 222 have the said ripple, since the DOC unit 260 is active, the DOC unit can be determined to show poor performance, as this fully functional causes combustion of supplied fuel. In the event of complete combustion of fuel during diagnosis of said DOC unit 260, said second NOR sensor 222 shall not exhibit said ripple if said DOC unit 260 is operating as intended.
    Figure 3b schematically illustrates a diagram, according to an embodiment of the invention.
    This illustrates how a NOR sensor, for example the first NOR sensor 221 and the second NOR sensor 222, is affected by the occurrence of exhaust gas in the exhaust gas purification system 289. The NOR sensors 221, 222 can be affected in such a way that their output signals are comprises a high-frequency oscillating signal as well as a relative decrease in the level of NOR content, as shown in Figure 3a. Figure 3b illustrates the said relative decrease with the letter L.
    Alternatively, said NOR sensors 221, 222 may be actuated in such a way that their output signals include a relative decrease in the level of NOR content, without said high frequency oscillation being feedable.
    During a time period T1 to T2, a small amount of fuel is supplied to the said DOC unit 260, while this is activated. In this case, said NOx sensors exposed to industry 22 exhibit said high-frequency oscillation and / or the said relative temporary decrease L of NOR content.
    In cases where both the first NOR sensor 221 and the second NOR sensor 222 exhibit said reduction of NOR content and / or ripple, since the DOC unit 260 is active, the DOC unit can be determined to show poor performance, since this fully functioning facilitates the combustion of supplied fuel. In the event of complete combustion of fuel during diagnosis of said DOC unit 260, said second NOR sensor 222 shall not exhibit said ripple if said DOC unit 260 is operating as intended. During a predetermined operating case if the vehicle 100 has a lowering of the said NOR levels, when exposing the fuel has the NOR sensors, indicate that the DOC unit does not show satisfactory performance.
    Said relative decrease L may correspond to, for example, 10%.
    Figure 3c schematically illustrates a diagram, according to an embodiment of the invention. It is illustrated that a lot of fuel is dosed to the said DOC unit 260. Industry dosing is carried out according to the inventive method when the DOC unit 260 is active. According to this exemplary embodiment, fuel metering takes place during a time period T1-12, whereby the inventive diagnosis of the DOC unit 260 can be carried out. Fuel metering can take place in a controlled manner by means of said motor 231 and / or said fuel metering means 233.
    It should be noted that when the first NOx sensor 221 and the second NOR sensor 222 are exposed to industry, error signals may be sent from the first NOR sensor 221 and the second NOR sensor 222, respectively, to the first control unit 200. In this case, the inventive method the diagnosis of said DOC unit 260 is performed on the basis of said error signals indicating occurrence of industry has said first NOx sensor 221 and said second NOR sensor 222, respectively.
    In this case, the following three parameters, individually or in combination, can be used according to the inventive method for diagnosing a DOC unit having an exhaust gas purification system. 23 The three parameters are: High frequency oscillation of NO, - content; Relative collection of NOx content; Fault signaling from NO, sensor.
    Figure 4a schematically illustrates a flow chart of a process in an exhaust gas purification system including a DOC unit 260 arranged downstream of an internal combustion engine 231. The process comprises a first process stage s401. Step s401 includes the steps of: - determining a first NO, - content of exhaust gases upstream of said DOC unit 260; - determining a second NO, - content has exhaust gases downstream of said DOC unit 260; - start up and fuel the said DOC unit 260; and - diagnosing said DOC unit 260 on the basis of said first NO, content and said second NO, content during a relatively small supply of fuel per unit of time for the DOC unit 260. After procedure step s401, the procedure is terminated.
    Figure 4b schematically illustrates a flow chart of a process in an exhaust gas purification system including a DOC unit 260 arranged downstream of an internal combustion engine 231.
    The process includes a first process step s410. The process step s410 may include the step of determining a radiating temperature having the said DOC unit 260. This may be done in an appropriate manner. The said temperature has the DOC unit 260 can be fed directly by means of a temperature sensor. Alternatively, said temperature can be modeled / calculated / estimated / determined in an appropriate manner, for example by means of said first control unit 200 on the basis of a determined exhaust gas temperature in the first passage 235 and / or a determined exhaust mass flow. After the procedure step s410, a subsequent procedure step s420 is performed.
    The process step s420 comprises the step of determining a state has said DOC unit 260. This can be done on the basis of said temperature having said DOC unit 260. If said radiating temperature has said DOC unit 260 exceeds a predetermined reference temperature Tref it is determined that said DOC unit 260 unit 260 is active / tooth / active. If said radiating temperature has said DOC unit 260 24 below said predetermined reference temperature Tref it is established that said DOC unit 260 is not active / tooth / active.
    It should be noted that dosing of fuel to the first passage 235 can be performed by controlling operation of said motor 231 and / or direct injection of fuel into the first passage 235 by means of the fuel dosing unit 233. This can be done in Procedure steps s410, s420 and / or s430 . When diagnosing the said DOC unit 260, a small supply of fuel must be provided. Thus, fuel supply can take place immediately before diagnosis of said DOC unit 260 and / or substantially at the same time as diagnosis of said DOC unit 260 is performed.
    According to one embodiment, the reducing agent dosage is completely turned off. According to one embodiment, a variable reducing agent dosage may be provided. According to both of these embodiments, advantageously improved detection of NOR content in exhaust gases can be achieved.
    After the procedure step s420, a subsequent procedure step s430 is performed.
    The method step s430 comprises the steps of continuously determining said first NON content by means of said first NOR sensor 221 and continuously determining said second NOR content by means of said second NOR sensor 222.
    The method step s430 may also comprise determining whether error signaling occurs in the first NOR sensor 221 and the second NOR sensor 222.
    This can be done by means of the first control unit 200.
    Step s430 may include the step of determining the presence of at least a flag of the four pitches: 1) High frequency oscillation of NOR content; 2) Relative collection of NON content; Fault signaling from NOR sensor; Relative increase of the second NOR content.
    After the step step s430, a subsequent step s440 is performed.
    Step s440 may include the step of diagnosing said DOC unit 260 on the basis of signaling from said first NON sensor 221 and said second NON sensor 222. Said diagnosis may be performed by said first control unit 200 according to routines stored therein. Said diagnosis can be performed on the basis of said first NON content and / or said second NON content. Said diagnosis can be performed on the basis of at least a flag of the parameters / pitches 1-3, which are indicated in procedure step s430 above.
    Said diagnosis of said DOC unit 260 can be performed during low industry supply to said DOC unit 260, which DOC unit 260 is active / tooth according to an aspect of the inventive method.
    Said diagnosing said DOC unit 260 involves determining erasing performance and / or a mat of performance degradation relative to a reference condition.
    Said reference state may be a state when said DOC unit has not been used and is newly manufactured. Said reference state may be a predetermined state, which may be empirically determined.
    After the step step s440, a subsequent step step s450 is performed.
    The method step s450 comprises the step of presenting a result of said diagnosis of said DOC unit 260. This can be done by means of said presentation means 220 and said first control unit 200. In this case a result concerning said diagnosis can be presented for e.g. an operator has the vehicle, fat-are or service staff.
    After procedure step s450, the procedure is terminated.
    Referring to Figure 5, a diagram of an embodiment of a device 500 is shown.
    The controllers 200 and 210 described with reference to Figure 2a and Figure 2b may in one embodiment comprise the device 500. The device 500 comprises a non-volatile memory 520, a data processing unit 510 and a read / write memory 550. The non-volatile memory 520 has a The first memory portion 530 of a computer program, such as an operating system, is stored to control the operation of the device 500. Further, the device 500 includes a bus controller, a serial communication port, I / O means, an A / D converter, a time and date input and transfer unit, a trade calculator and an interrupt controller (not shown). The non-volatile memory 520 also has a second memory portion 540.
    A computer program P is provided for controlling the diagnosis of an exhaust gas purification system including a DOC unit disposed downstream of an internal combustion engine.
    The computer program P may include routines for determining a first NON content of exhaust gases upstream of said DOC unit 260. The computer program P may include routines for determining a second NON content of exhaust gases downstream of said DOC unit 260. The computer program P may include routines for starting up and fueling said DOC unit 260. The computer program P may include routines for diagnosing said DOC unit 260 on the basis of said first NOR content and said second NOR content during a relatively small fuel supply per unit time for DOC unit 260.
    The computer program P may comprise routines for following changes in said first NON content and said second NON content during a period of said low industry supply, whereby changes in the form of a decrease in fixed NOR content and high frequency oscillation in said first NOR content and said other NOR content is taken as an indication of industry occurrence in said exhaust gases.
    The computer program P may include routines for comparing changes in said first NOR content and said second NOR content, whereby a lack of function of said DOC unit 260 is taken as a conclusion if industry occurrence in said exhaust gases is found by means of similar changes in said first NOR content. and said second NOR content.
    The computer program P may comprise routines for taking malfunction of the DOC unit 260 which is concluded in the event of a signal regarding malfunction due to fuel occurrence in said exhaust gases in connection with the feeding of said first NOR content and the feeding of said second NOR content. The computer program P may comprise routines for ceasing a supply of reducing agent to said exhaust gases in order to improve the determination of a course of said second NON content.
    The program P can be stored in an executable manner or in a compressed manner in a memory 560 and / or in a read / write memory 550.
    When it is described that the data processing unit 510 performs a certain function, it should be understood that the data processing unit 510 performs a certain part of the program which is stored in the memory 560, or a certain part of the program which is stored in the read / write memory 550.
    The data processing device 510 can communicate with a data port 599 via a data bus 515. The non-volatile memory 520 is intended for communication with the data processing unit 510 via a data bus 512. The separate memory 560 is intended to communicate with the data processing unit 510 via a data bus 511. Read / write memory 550 is arranged to communicate with the data processing unit 510 via a data bus 514. To the data port 599, e.g. the lanes L210, L250, L292, L221, L222, L233 and L241 are connected (see Figure 2a and Figure 2b).
    When data is received on the data port 599, it is temporarily stored in the second memory part 540. Once the received input data has been temporarily stored, the data processing unit 510 is ready to perform code execution in a manner described above. According to one embodiment, signals received at the data port 599 comprise information about a said first NOR content and said second NOR content. According to one method, signals received at the data port 599 include information about the estimated / calculated / matt / fixed / modeled temperature of the DOG 260. According to one embodiment, signals received at the data port 599 include information about whether the DOC unit 260 is active or not.
    Parts of the methods described herein may be performed by the device 500 by means of the data processing unit 510 which the cat program stored in the memory 560 or 28 read / write memory 550. When the device 500 runs the program, the methods described are executed.
    The foregoing description of the preferred embodiments of the present invention has been provided for the purpose of illustrating and describing the invention. It 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. The embodiments were selected and described in order to best explain the principles of the invention and its practical applications, thereby enabling those skilled in the art to understand the invention for various embodiments and with the various modifications which are appropriate to the intended use. 29
    权利要求:
    Claims (14)
    [1]
    A method of an exhaust gas purification system comprising a DOC unit (260) arranged downstream of an internal combustion engine (231), comprising the steps of: - determining a first NO content of exhaust gases upstream of said DOC unit (260); - determining a second NO, - content has exhaust gases downstream of said DOC unit (260); - start up and trade in the said DOC unit (260); characterized by the steps of: - diagnosing said DOC unit (260) on the basis of said first NO, content and said second NO, content during a relatively small fuel supply per unit time for the DOC unit (260).
    [2]
    The method of claim 1, further comprising the step of: - following changes in said first NO, content and said second NO, content during a period of said low fuel supply, wherein changes in the form of a decrease (L) of fixed NO , - content and / or high-frequency oscillation has the said first NO „content and the said second NO, content is taken as an indication of the presence of fuel in the said exhaust gases.
    [3]
    A method according to claim 1 or 2, further comprising the step of: - comparing changes having said first NO 2 content and said second NO 2 content, wherein a malfunction has said DOC unit (260) being concluded as an industry occurrence in said exhaust gases are ascertained by means of similar changes having said first NO, content and said second NO, content.
    [4]
    A method according to any one of claims 1-3, further comprising the step of: - taking the malfunction has the DOC unit (260) concluded in the event of a signal regarding malfunction due to the presence of fuel in said exhaust gases in connection with the feeding of said first NON content and the feed of said second NOR content.
    [5]
    A method according to any one of the preceding claims, comprising the step of: - ceasing to supply a reducing agent to said exhaust gases in order to improve the determination of a process having said second NOR content.
    [6]
    Apparatus in an exhaust gas purification system comprising a DOC unit (260) arranged downstream of an internal combustion engine (231), comprising: - means (200; 210; 500; 221) adapted to determine a first NO), - content of exhaust gases upstream of said DOC unit (260); means (200; 210; 500; 222) adapted to determine a second NOR content of exhaust gases downstream of said DOC unit (260); means (200; 210; 500; 233; 231) adapted to start up said DOC unit (260); means (200; 210; 500; 233; 231) adapted to supply fuel to said DOC unit (260); characterized by: - means (200; 210; 500) adapted to diagnose said DOC unit (260) on the basis of said first NOR content and said second NOR content during a relatively small industry supply per unit time for the DOC unit (260) .
    [7]
    Device according to claim 6, comprising: - means (200; 210; 500; 221; 222) adapted to follow changes in said first NON content and said second NOR content during a period of said low industry supply, wherein changes in form of a decrease (L) of fixed NON content and / or high-frequency oscillation of said first NOR content and said second NOR content is taken as an indication of the occurrence of fuel in said exhaust gases.
    [8]
    Device according to claim 6 or 7, comprising: - means (200; 210; 500) adapted to compare changes of said first NOR content and said second NOR content, wherein a lack of function of said DOC unit (260) is taken as a conclusion if the occurrence of fuel in the said exhaust gases is ascertained by means of similar changes in the said first NOR content and the said second NOR content.
    [9]
    Device according to any one of claims 6-8, comprising: - means (200; 210; 500) adapted to take a malfunction of the DOC unit (260) which is concluded in the event of a signal regarding malfunction to 1614 of 31 industry instances in said exhaust gases in connection with the feeding of said first NON content and the feeding of said second NON content.
    [10]
    Device according to any one of claims 6-9, comprising: - means (200; 210; 500; 250) adapted to cease with a supply of reducing agent to said exhaust gases in order to improve the determination of a course of said second NON content.
    [11]
    A motor vehicle (100; 110) comprising an SCR system according to any one of claims 6-10.
    [12]
    A motor vehicle (100; 110) according to claim 11, wherein the motor vehicle is any of a truck, bus or passenger car.
    [13]
    Computer program (P) in an exhaust gas purification system, wherein said computer program (P) comprises program code for causing an electronic control unit (200; 500) or another computer (210; 500) connected to the electronic control unit (200; 500) to execute the steps according to any one of claims 1-5.
    [14]
    A computer program product comprising a program code stored on a computer readable medium for performing the method steps of any of claims 1-5, when said program code is crossed on an electronic control unit (200; 500) or another computer (210; 500) connected to the electronic control unit (200; 500). 1 / or 100 112
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    同族专利:
    公开号 | 公开日
    SE538547C2|2016-09-13|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    法律状态:
    2021-08-31| NUG| Patent has lapsed|
    优先权:
    申请号 | 申请日 | 专利标题
    SE1450080A|SE538547C2|2014-01-29|2014-01-29|Device and method of an exhaust gas purification system|SE1450080A| SE538547C2|2014-01-29|2014-01-29|Device and method of an exhaust gas purification system|
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