JP2013256910A - NOx ADAPTATION DEVICE, NOx ADAPTATION METHOD, AND PROGRAM - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce time and costs required for adaptation of an NOx model.SOLUTION: NOx model adaptation devices 1 and 1a include: a virtual map preparing part 16 which inputs information showing behavior of an engine 4 recorded by a measurement file preparing part 11 with respect to a virtual NOx model 7a equivalent to an NOx model 7 which an ECU 5 has, and prepares a virtual map 15 showing correspondence relation of the behavior of the engine 4 obtained by the result of the input information and an estimated value of an exhaust amount of nitrogen oxide; and a map comparing part 17 which determines a parameter in which the estimated value of the exhaust amount of the nitrogen oxide by the virtual map 15 is consistent with an actual measurement value of an exhaust amount of the nitrogen oxide of an actual measurement map 12, in the behavior of the same engine 4.

Description

  The present invention relates to a NOx adaptation device, a NOx adaptation method, and a program.

  Vehicles using urea SCR (Selective Catalytic Reduction) are widely used to remove nitrogen oxides (hereinafter referred to as NOx) contained in exhaust gas of diesel engines (see, for example, Patent Document 1). In the urea SCR, an amount of urea water commensurate with the amount of NOx discharged is supplied to the SCR catalyst.

  For this reason, it is required to estimate the amount of NOx discharged from the engine according to various behaviors of the engine. For this reason, for example, a method using a NOx model in which NOx emissions corresponding to various behaviors of the engine are mapped is employed (see, for example, Patent Document 2).

  Such a NOx model is generally provided in an engine control unit (ECU) by an engine manufacturer. In the NOx model shipped from the manufacturer, default values of parameters for the NOx model to estimate the NOx emission amount are set. Since the default value of the parameter is, for example, the value in the steady state of the engine, in order to set the parameter according to the transient behavior of the engine, the parameter of the NOx model is changed after the engine is actually mounted on the vehicle. Therefore, it is necessary to adapt to the actual vehicle.

  As a method for adapting the NOx model, the vehicle is actually driven under various circumstances, the NOx emission amount corresponding to various behaviors of the engine is actually measured, and the estimated NOx emission amount of the NOx model is changed to the actual measurement value. A method of changing the parameters of the NOx model so as to approach is adopted.

JP 2009-293606 A JP 2011-111924 A

  In the NOx model adaptation method described above, since the NOx model is adapted while actually running the vehicle many times, much time and cost are required for the adaptation. For example, the adaptation of the NOx model is preferably performed for the total number of vehicles. However, since it takes a lot of time and money, the NOx model is adapted for the total number of vehicles, such as one for each vehicle type. Problems such as difficult to implement.

  The present invention has been made under such a background, and an object thereof is to provide a NOx adapting apparatus, a NOx adapting method, and a program capable of reducing the time and cost required for adapting a NOx model. And

  The apparatus for adapting NOx model of the present invention is a NOx model for estimating a nitrogen oxide emission amount that changes in accordance with the behavior of the engine, and is a NOx model comprising parameters for estimating the nitrogen oxide emission amount. In the NOx model fitting device that improves the estimation accuracy of the vehicle, a measuring means for recording the amount of nitrogen oxides discharged from the engine according to the behavior of the engine while the vehicle is running, and the behavior of the engine obtained by the measuring means, An actual measurement map creation means for creating an actual measurement map showing a correspondence relationship with an actual measurement value of nitrogen oxide emission, and a virtual NOx model equivalent to the NOx model of the control device, the engine recorded by the measurement means Enter information indicating the behavior and create a virtual map that shows the correspondence between the resulting engine behavior and the estimated nitrogen oxide emissions. A virtual map creation means, and a determination means for determining a parameter in which the estimated value of the nitrogen oxide emission amount of the virtual map and the actual measurement value of the nitrogen oxide emission amount of the actual measurement map coincide with each other in the same engine behavior. It is what you have.

  A NOx model fitting method according to another aspect of the present invention is a NOx model for estimating a nitrogen oxide emission amount that changes according to engine behavior, and for estimating a nitrogen oxide emission amount. In the NOx model fitting method executed by the NOx model fitting device for improving the estimation accuracy of the NOx model consisting of parameters, a measurement step for recording the amount of nitrogen oxides discharged from the engine according to the behavior of the engine while the vehicle is running And an actual measurement map creating step for creating an actual measurement map showing a correspondence relationship between the engine behavior obtained by the processing of the measurement step and the actual measurement value of nitrogen oxide emission, and a virtual equivalent to the NOx model of the control device The information indicating the engine behavior recorded by the measurement step process is input to the NOx model, and the resulting nitrogen is obtained. A virtual map creation step for creating a virtual map showing the correspondence between the engine behavior and the estimated value of nitrogen oxide emissions from the estimated value of the emission of fluoride, and the nitrogen oxidation of the virtual map in the same engine behavior And a determination step for determining a parameter that matches the estimated value of the emission amount of the object and the actually measured value of the nitrogen oxide emission amount of the actual measurement map.

  Still another aspect of the present invention is a program. The program of the present invention causes the information processing apparatus to realize the function of the NOx model matching apparatus of the present invention.

  According to the present invention, the time and cost required for fitting the NOx model can be reduced.

1 is an overall configuration diagram of a NOx compatible device according to an embodiment of the present invention. It is a flowchart which shows operation | movement of the NOx compatible apparatus of FIG. It is a flowchart which shows the procedure of the comparative example for demonstrating the effect of the NOx adaptation apparatus which concerns on embodiment of this invention.

  The configuration of the NOx adapting devices 1 and 1a according to the embodiment of the present invention will be described with reference to FIG. The NOx compatible devices 1, 1 a are divided into a configuration (reference numeral 1) provided on the vehicle 2 side and a configuration (reference numeral 1 a) provided at a location different from the vehicle 2. The functions of the NOx compatible devices 1 and 1a are realized by the information processing devices 3 and 3a executing a program installed in advance in a memory (not shown) of the information processing devices 3 and 3a.

  The vehicle 2 includes an engine 4 and a control device (hereinafter referred to as ECU) 5 for controlling the engine 4. The engine 4 has an exhaust pipe 6, and exhaust gas generated by the engine 4 is exhausted from the exhaust pipe 6. The ECU 5 is an information processing device that realizes a control function of the engine 4 by executing a program installed in advance. Moreover, it has the NOx model 7 as a part of function of ECU5.

  The first configuration of the NOx compatible device 1 provided on the vehicle 2 side is an exhaust gas analysis unit 8 that analyzes the amount of NOx contained in the exhaust gas exhausted from the exhaust pipe 6. In the example of FIG. 1, exhaust gas is introduced from the outer wall of the exhaust pipe 6 into the exhaust gas analysis unit 8 via the branch pipe P. However, the exhaust gas introduction path to the exhaust gas analyzer 8 may be any way.

  Subsequently, a second configuration is an ECU signal recording unit 9 that records an ECU signal sent when the ECU 5 controls the engine 4. Recording the ECU signal sent when the ECU 5 controls the engine 4 is the same as recording the behavior of the engine 4.

  Subsequently, the third configuration is a measurement file creation unit 11 that inputs the collected data of the exhaust gas analysis unit 8 and the ECU signal recording unit 9 and creates the measurement file 10. That is, the measurement file creation unit 11 acquires NOx emission data based on the collected data of the exhaust gas analysis unit 8, and acquires behavior data of the engine 4 based on the collected data of the ECU signal recording unit 9. Then, the measurement file creation unit 11 creates the measurement file 10 in which the NOx emission amount corresponding to the behavior of the engine 4 is recorded over time. The measurement file 10 is stored in the memory M of the information processing apparatus 3.

  The above exhaust gas analysis unit 8, ECU signal recording unit 9, and measurement file creation unit 11 correspond to measurement means.

  The first configuration of the NOx compatible device 1a provided at a different location from the vehicle 2 is an actual measurement map creation unit 13 that creates an actual measurement map 12 that maps NOx emission amounts over time based on the measurement file 10. . The measurement file 10 is read from the memory M of the information processing device 3 on the vehicle 2 side and stored in the memory M1 of the information processing device 3a. Alternatively, the memory M of the information processing apparatus 3 is a removable memory, and the memory M is extracted from a slot (not shown) of the information processing apparatus 3 and inserted into a slot (not shown) of the information processing apparatus 3a. The memory M of the device 3 may be directly used as the memory M1 of the information processing device 3a.

  Subsequently, the second configuration is a virtual ECU 5a (virtual NOx model) in which a program for realizing the function of the ECU 5 (including the NOx model 7) on the vehicle 2 side is copied to the memory M2 of the information processing device 3a. 7a including a simulation execution unit 14 for performing simulation.

  Subsequently, the third part of the configuration is information indicating the behavior of the engine 4 recorded in the measurement file 10 virtually reproduced by simulation for the NOx model 7a copied and stored in the memory M2. It is a virtual map creation unit 16 that inputs an ECU signal and creates a virtual map 15 showing the correspondence between the behavior of the engine 4 and the NOx emission obtained as a result.

  Subsequently, the fourth configuration is that the actual map 12 is compared with the virtual map 15 until the estimated NOx emission amount by the virtual map 15 matches the NOx emission amount of the actual map 12. 7a is a map comparison unit 17 that repeatedly performs the process of sequentially changing the parameter for estimating the NOx emission amount.

  Here, the parameter for the virtual NOx model 7a to estimate the NOx emission amount is, for example, if the virtual NOx model 7a is a polynomial approximation model, the parameter is engine rotation as a control value of the engine 4. Speed, fuel injection amount, etc.

  Next, the operation of the NOx conforming apparatus 1a will be described with reference to the flowchart of FIG. In the flowchart of FIG. 2, the condition of “START” is that the measurement file creation unit 11 of the NOx compatible device 1 on the vehicle 2 side completes the creation of the measurement file 10, and the measurement file 10 is stored in the memory M1 of the information processing device 3a. And a program for realizing the function of the ECU 5 (including the NOx model 7) on the vehicle 2 side is stored as a virtual ECU 5a (including the virtual NOx model 7a) in the memory M2 of the information processing apparatus 3. In this state, the information processing apparatus 3 is activated.

  In step S1, the actual measurement map creation unit 13 of the information processing device 3 creates the actual measurement map 12 based on the measurement file 10 stored in the memory M1, and the flow proceeds to step S2. For example, the actual measurement map creation unit 13 creates a map (graph) in which the vertical axis represents NOx emission and the horizontal axis represents time (that is, the behavior of the engine 4).

  In step S2, the simulation execution unit 14 of the information processing device 3 applies to the virtual ECU 5a (including the virtual NOx model 7a) stored in the memory M2 based on the measurement file 10 stored in the memory M1. A simulation is performed, and the flow proceeds to step S3.

  In step S3, the virtual map creation unit 16 of the information processing device 3 creates the virtual map 15 based on the estimated amount of NOx estimated by the virtual NOx model 7a as a result of the simulation in step S2. Proceed to S4. The virtual map 15 is a map (graph) in which, for example, the vertical axis represents NOx emission and the horizontal axis represents time (that is, the behavior of the engine 4).

  In step S4, the map comparison unit 17 of the information processing device 3 determines whether or not the actual measurement map 12 and the virtual map 15 match. If it is determined in step S4 that the actual measurement map 12 and the virtual map 15 match, the flow proceeds to step S5. On the other hand, if it is determined in step S4 that the actual measurement map 12 and the virtual map 15 do not match, the flow proceeds to step S6. The fact that the actual measurement map 12 and the virtual map 15 match each other means that the shape of the curve drawn by the actual measurement map 12 is similar to the shape of the curve drawn by the virtual map 15.

  In step S5, the map comparison unit 17 of the information processing device 3 determines the control value (parameter) of the virtual NOx model 7a and ends the process (END).

  In step S6, the map comparison unit 17 of the information processing device 3 changes the control value (parameter) of the virtual NOx model 7a and returns to the flow of step S2.

  Thereby, the control value in which the actual measurement map 12 and the virtual map 15 correspond is set to the virtual NOx model 7a. Thereafter, the virtual NOx model 7a in the memory M2 of the information processing device 3a is overwritten with the NOx model 7 in the ECU 5 of the vehicle 2. In this way, the NOx emission amount according to the behavior of the engine 4 estimated by the NOx model 7 in the ECU 5 of the vehicle 2 is substantially equal to the NOx emission amount according to the actually measured behavior of the engine 4, and the NOx model. The accuracy of the estimation result of the NOx emission amount of 7 is high.

  Next, a conventional NOx model fitting method will be described as a comparative example with reference to the flowchart of FIG. However, conventionally, the NOx adaptation devices 1 and 1a do not automatically perform the adaptation process of the NOx model as in the present embodiment described above. Therefore, the process of the flowchart of FIG. 3 is a procedure performed by an operator (person).

  In step S10, the operator acquires the actual measurement result of the NOx emission amount according to the behavior of the engine 4 while actually running the vehicle 2, and the flow proceeds to step S11.

  In step S11, the operator acquires an estimation result of the NOx emission amount according to the behavior of the engine 4 estimated by the NOx model 7 during the travel of step S11, and the flow proceeds to step S12.

  In step S12, the operator determines whether or not the actual measurement result acquired in step S10 matches the estimation result acquired in step S11. If it is determined in step S12 that the actual measurement result acquired in step S10 matches the estimation result acquired in step S11, the flow proceeds to step S13. On the other hand, if it is determined in step S12 that the actual measurement result acquired in step S10 and the estimation result acquired in step S11 are inconsistent, the flow proceeds to step S14.

  In step S13, the operator determines the control value (parameter) of the NOx model 7 and ends the process (END).

  In step S14, the operator changes the control value (parameter) and returns to the flow of step S10.

  Thus, conventionally, the NOx model 7 is adapted by repeatedly executing the process of actually running the vehicle 2. On the other hand, if the NOx conforming apparatus 1 according to the present embodiment is used and the NOx conforming method of the present embodiment shown in FIG. 2 is performed, the step of actually running the vehicle 2 is step S1 in FIG. It can be suppressed to only one step. Thereby, according to the NOx adaptation apparatus 1 and the NOx adaptation method according to the present embodiment, the time and cost required for adaptation of the NOx model 7 can be significantly reduced.

  That is, the NOx conforming apparatus 1 records the amount of nitrogen oxides discharged from the engine 4 according to the behavior of the engine 4 while the vehicle 2 is traveling, and the measured value of the behavior of the engine 4 and the amount of nitrogen oxide discharged. The actual measurement map 12 showing the correspondence relationship between the engine 4 and the ECU 5 is input to the virtual NOx model 7a equivalent to the NOx model 7 of the ECU 5 and the recorded information indicating the behavior of the engine 4 is input. A virtual map 15 showing the correspondence between the behavior of FIG. 4 and the estimated value of nitrogen oxide emission is created, and the estimated value of nitrogen oxide emission of the virtual map 15 and the actual measurement map 12 in the same behavior of the engine 4 are created. Since the parameter that matches the actual measured value of the nitrogen oxide emission amount is determined, the time and cost required for fitting the NOx model 7 can be reduced.

  The embodiment of the present invention can be variously modified without departing from the gist thereof. For example, the functions of the exhaust gas analysis unit 8, the ECU signal recording unit 9, and the measurement file creation unit 11 may be incorporated in the ECU 5 as part of the functions of the ECU 5.

  In addition, the program executed by the information processing apparatuses 3 and 3a has been described as being preinstalled in the information processing apparatuses 3 and 3a, but the removable medium on which the program is recorded (the program is stored) is not used. A program that is installed in the illustrated drive or the like and is read from a removable medium, stored in a nonvolatile memory inside the information processing apparatus 3 or 3a, or transmitted via a wired or wireless transmission medium May be installed in the information processing devices 3 and 3a by being received by a communication unit (not shown) and stored in a nonvolatile memory inside the information processing devices 3 and 3a.

DESCRIPTION OF SYMBOLS 1,1a ... NOx adaptation apparatus, 2 ... Vehicle, 3,3a ... Information processing apparatus, 4 ... Engine, 5,5a ... ECU (control apparatus), 7 ... NOx model, 7a ... Virtual NOx model, 8 ... Exhaust gas Analysis unit (part of measurement unit), 9 ... ECU signal recording unit (part of measurement unit), 10 ... measurement file, 11 ... measurement file creation unit (part of measurement unit), 12 ... actual measurement map, 13 ... Measured map creation unit (actual map creation unit), 14 ... Simulation execution unit (part of virtual map creation unit), 15 ... Virtual map, 16 ... Virtual map creation unit (virtual map creation unit), 17 ... Map comparison unit ( Map comparison means)

Claims (3)

NOx model for estimating NOx emissions that vary according to engine behavior and improving NOx model estimation accuracy consisting of parameters for estimating NOx emissions In the device
Measuring means for recording the amount of nitrogen oxides exhausted from the engine according to the behavior of the engine while the vehicle is running;
An actual measurement map creating means for creating an actual measurement map showing a correspondence relationship between the behavior of the engine obtained by the measurement means and the actual measurement value of the emission amount of nitrogen oxides;
Information indicating the behavior of the engine recorded by the measuring means is input to a virtual NOx model equivalent to the NOx model of the control device, and the behavior of the engine and the nitrogen oxide obtained as a result are input. A virtual map creating means for creating a virtual map showing a correspondence relationship with the estimated value of the emission amount of
In the same behavior of the engine, a determination unit that determines the parameter in which the estimated value of the nitrogen oxide emission amount of the virtual map matches the actual measurement value of the nitrogen oxide emission amount of the actual measurement map;
Having
NOx model fitting device characterized by the above. NOx model for estimating NOx emissions that vary according to engine behavior and improving NOx model estimation accuracy consisting of parameters for estimating NOx emissions In the NOx model fitting method executed by the apparatus,
A measuring step for recording an amount of nitrogen oxides exhausted from the engine according to a behavior of the engine during traveling of the vehicle;
An actual measurement map creating step for creating an actual measurement map indicating a correspondence relationship between the behavior of the engine obtained by the process of the measurement step and the actual measurement value of the emission amount of the nitrogen oxide;
Information indicating the behavior of the engine recorded by the process of the measurement step is input to a virtual NOx model equivalent to the NOx model of the control device, and the nitrogen oxide emission amount obtained as a result is input. A virtual map creating step for creating a virtual map indicating the correspondence between the behavior of the engine and the estimated value of the emission amount of nitrogen oxides from the estimated value;
In the same behavior of the engine, a determination step of determining the parameter at which the estimated value of the nitrogen oxide emission amount of the virtual map and the actually measured value of the nitrogen oxide emission amount of the actual measurement map coincide with each other;
Having
The NOx model fitting method characterized by this.   A program for causing an information processing apparatus to realize the function of the NOx model matching apparatus according to claim 1.

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