A control system and method for vehicle-mounted exhaust gas purification equipment

Abstract

The invention discloses a control system and method for vehicle-mounted exhaust gas purification equipment, and relates to the technical field of equipment control and maintenance. The control system comprises an exhaust gas purification equipment control module, a reference data analysis module, an equipment maintenance condition setting module and an equipment maintenance management module. The exhaust gas purification equipment control module is used for controlling vehicle exhaust gas purification after the vehicle is started. The reference data analysis module is used for collecting and analyzing historical data of vehicle travel distance and urea nozzle blockage caused by urea crystals formed by urea aqueous solution, so as to generate a filter element maintenance reference model of a urea pump. The equipment maintenance condition setting module is used for setting conditions for triggering a urea pump filter element replacement operation. The equipment maintenance management module is used for predicting the time for performing a filter element replacement operation, and prompting a vehicle owner to perform the replacement operation at the predicted time, thereby realizing adaptive dynamic adjustment of the urea pump filter element replacement time, and reducing the probability that the nozzle is blocked by urea crystals and affects the normal purification of vehicle exhaust gas and the normal operation of the vehicle.

Description

Technical Field

[0001] The present invention relates to the technical field of equipment control and maintenance, and in particular to a control system and method for vehicle-mounted exhaust gas purification equipment. Background Art

[0002] In order to make the exhaust emission of diesel engines meet the requirements, higher requirements are put forward for the exhaust purification of diesel engines. For automotive diesel engines, two methods are generally used to achieve on-board exhaust purification. One is to use the exhaust gas recirculation ECR + exhaust particulate filter method, and the other is to use the selective reduction reaction SCR method to purify the exhaust gas. Among them, SCR is a device that injects liquid urea solution into the exhaust gas of automotive diesel engines and evaporates it into ammonia and nitrogen oxides NOx discharged by the diesel engine in the high-temperature exhaust gas. Under the action of the catalyst in the catalyst, a reduction reaction occurs, thereby greatly reducing the NOx value until the emission requirements are met;

[0003] When using SCR for on-board exhaust gas purification, urea aqueous solution is used for vehicle exhaust gas purification. If the urea pump filter element is not replaced in time, urea crystals are easily formed and then the urea nozzle is easily blocked, thereby affecting the normal purification of vehicle exhaust gas and the normal operation of the vehicle. The prior art generally adopts the method of regularly replacing the urea pump filter element to prevent the urea nozzle from being blocked due to the untimely replacement of the filter element. However, the frequent changes in the vehicle operation conditions may cause urea crystals to affect the normal purification of vehicle exhaust gas and the normal operation of the vehicle before the filter element is replaced according to the original cycle. The filter element replacement cycle is fixed instead of adaptive dynamic adjustment, which is not conducive to reducing the probability of urea aqueous solution generating urea crystals to block the urea nozzle and thus affecting the normal purification of vehicle exhaust gas and the normal operation of the vehicle.

[0004] Therefore, people are in urgent need of a vehicle-mounted exhaust gas purification equipment control system and method to solve the above technical problems. Summary of the invention

[0005] The object of the present invention is to provide a control system and method for vehicle-mounted exhaust gas purification equipment to solve the problems raised in the prior art.

[0006] To achieve the above object, the present invention provides the following technical solutions: a vehicle-mounted exhaust gas purification equipment control system, comprising: an exhaust gas purification equipment control module, a reference data analysis module, an equipment maintenance condition setting module and an equipment maintenance management module;

[0007] The output end of the exhaust gas purification equipment control module is connected to the input end of the reference data analysis module, the output end of the reference data analysis module is connected to the input end of the equipment maintenance condition setting module, and the output end of the equipment maintenance condition setting module is connected to the input end of the equipment maintenance management module;

[0008] The exhaust gas purification equipment control module is used to perform vehicle exhaust gas purification control after the vehicle is started;

[0009] The reference data analysis module is used to collect and analyze the historical mileage of the vehicle and the historical data of urea crystals formed by the urea aqueous solution used for exhaust gas purification and causing urea nozzle blockage, and generate a filter element maintenance reference model for the urea pump;

[0010] The equipment maintenance condition setting module is used to set the conditions for triggering the urea pump filter element replacement operation according to the filter element maintenance reference model;

[0011] The equipment maintenance management module is used to predict the time for filter element replacement operation according to set conditions, and prompt the vehicle owner to perform the replacement operation at the predicted time.

[0012] Further, the exhaust gas purification equipment control module includes a vehicle operation sensing unit and a urea solution use control unit;

[0013] The output end of the vehicle operation sensing unit is connected to the input end of the urea solution use control unit;

[0014] The vehicle operation sensing unit is used to sense a vehicle start signal;

[0015] The urea solution control unit is used to control the urea metering injection device installed on the mixing tube to spray the urea aqueous solution after the exhaust gas comes out of the turbine and enters the exhaust mixing tube after the vehicle is started. The sprayed urea aqueous solution is used to purify the exhaust gas. Urea undergoes hydrolysis and thermal decomposition reactions at high temperature to generate NH3. NH3 is used to reduce NOX and discharge N2. Excess NH3 is also oxidized to N2, thereby achieving vehicle exhaust purification.

[0016] Further, the reference data analysis module includes an operation data acquisition unit, a congestion information acquisition unit and a reference model establishment unit;

[0017] The input end of the operation data acquisition unit is connected to the output end of the vehicle operation sensing unit, the output end of the operation data acquisition unit is connected to the input end of the congestion information acquisition unit, and the output end of the congestion information acquisition unit is connected to the input end of the reference model establishment unit;

[0018] The operation data collection unit is used to collect the distance data of the vehicle in the past, and collect the distance data of the vehicle when the urea nozzle is blocked due to urea crystallization when the urea pump filter element is replaced in the past;

[0019] The blockage information collection unit is used to collect information on the number of times the urea nozzle was blocked due to urea crystallization when the urea pump filter element was replaced when the vehicle traveled different distances in the past;

[0020] The reference model building unit is used to analyze the probability of urea crystallization causing urea nozzle blockage when the vehicle travels different distances, generate data points based on the travel distance and probability, and establish a filter element maintenance reference model after linear fitting of the data points.

[0021] Further, the equipment maintenance condition setting module includes a critical data input unit and a trigger condition setting unit;

[0022] The input end of the critical data input unit is connected to the output end of the reference model establishment unit, and the output end of the critical data input unit is connected to the input end of the trigger condition setting unit;

[0023] The critical data input unit is used to set a blockage probability threshold value, substitute the blockage probability threshold value into the filter element maintenance reference model, and predict the distance traveled by the vehicle when the urea pump filter element needs to be replaced. The predicted distance indicates that if the urea pump filter element is not replaced after the vehicle has traveled the corresponding distance, the urea nozzle is likely to be blocked;

[0024] The trigger condition setting unit is used to set the prediction result as a condition for triggering the urea pump filter element replacement operation.

[0025] Furthermore, the equipment maintenance management module includes a replacement time adjustment unit and a filter element replacement prompt unit;

[0026] The input end of the replacement time adjustment unit is connected to the output end of the trigger condition setting unit, and the output end of the replacement time adjustment unit is connected to the input end of the filter element replacement prompt unit;

[0027] The replacement time adjustment unit is used to retrieve the time when the vehicle has traveled to the predicted distance in the past, and predict the time when the vehicle will travel to the predicted distance next time based on the retrieved data;

[0028] The filter element replacement reminder unit is used to remind the vehicle owner to replace the urea pump filter element at a predicted time.

[0029] A method for controlling a vehicle-mounted exhaust gas purification device comprises the following steps:

[0030] S01: Perform vehicle exhaust purification control after the vehicle is started;

[0031] S02: Collect and analyze the historical mileage of the vehicle and the historical data of urea nozzle blockage caused by urea crystals formed by urea aqueous solution used for exhaust gas purification, and generate a reference model for filter element maintenance of the urea pump;

[0032] S03: Setting the conditions for triggering the urea pump filter element replacement operation according to the filter element maintenance reference model;

[0033] S04: Predicting the time for filter element replacement operation based on set conditions, and prompting the vehicle owner to perform the replacement operation at the predicted time.

[0034] Furthermore, in step S01: after the vehicle is started, the exhaust gas enters the exhaust mixing pipe after coming out of the turbine, and the urea metering injection device installed on the mixing pipe is controlled to inject the urea aqueous solution, and the injected urea aqueous solution is used to purify the exhaust gas.

[0035] Further, in step S02: the distance set that the vehicle has traveled when the urea nozzle is blocked due to urea crystallization when the urea pump filter is replaced in the past is collected as D={D 1 , D 2 , …, D i , …, D m}, urea nozzle refers to the nozzle of the urea metering injection device, where m represents the number of distance items. When the vehicle travels to the distance in the set D, the number of times the urea nozzle is blocked by urea crystallization when the urea pump filter is replaced is F={F 1 , F 2 , …, F i , …, F m}, F i Indicates that the vehicle travels a distance of D i The number of times the urea nozzle is found to be blocked is calculated according to the formula R i =F i / ∑ m i=1 (F i ) Calculate the vehicle's travel distance to D i The probability R that urea crystals will cause urea nozzle blockage i The probability set of urea crystallization causing urea nozzle blockage when the vehicle travels to different distances is calculated as R={R 1 , R 2 , …, R i , …, R m}, generate data points {(D 1 , R 1 ), (D 2 , R 2 ),…,(D i , R i ),…,(D m , R m )}, and then a filter element maintenance reference model is established by performing a straight line fitting on the generated data points:

[0036] y=γ*x+β;

[0037] Among them, * represents the multiplication sign, γ and β represent the fitting coefficients, x represents the independent variable referring to the vehicle driving distance in the filter element maintenance reference model, and y represents the dependent variable referring to the probability of urea nozzle blockage in the filter element maintenance reference model;

[0038] When the vehicle's mileage reaches a certain level, the urea pump filter needs to be replaced in time to reduce the problem of crystallization of urea aqueous solution and nozzle blockage caused by untimely filter replacement. Considering the different urea solutions used in exhaust gas purification, different exhaust gas purification performance, and different vehicle driving conditions of different vehicles, different vehicles may cause blockage problems when their mileage reaches different values. The historical driving data of the vehicle is collected through big data technology, and the mileage of the vehicle in the past is analyzed to determine when crystallization is likely to form and cause nozzle blockage. The historical blockage probability and mileage are used as reference data to establish a filter maintenance reference model, which provides accurate reference data for subsequent judgment of the mileage of the vehicle when the urea pump filter needs to be replaced.

[0039] Further, in step S03: the blockage probability threshold is set to p, and the blockage probability threshold is substituted into the filter element maintenance reference model: let y=p, and the predicted distance traveled by the vehicle when the urea pump filter element needs to be replaced is: (p-β) / γ, and the condition for triggering the urea pump filter element replacement operation is set to: the vehicle travel distance reaches (p-β) / γ.

[0040] Further, in step S04: retrieve the time interval set of the vehicle's previous travel distance reaching (p-β) / γ as T={T 1 , T 2 , …, T n}, where T 1 T represents the time interval between the time when the vehicle's previous driving distance reaches (p-β) / γ for the second time and the time when it reaches (p-β) / γ for the first time, n It represents the time interval between the time when the vehicle's previous driving distance reaches (p-β) / γ for the nth time and the time when it reaches (p-β) / γ for the n-1th time. The time when the driving distance reaches (p-β) / γ for the nth time is the time when the driving distance reaches (p-β) / γ most recently before the current time. The time when the vehicle reaches the predicted distance for the n+1th time is predicted according to the following formula:

[0041] T n+1 =(1-δ)*T n +δ*Z n ;

[0042] Among them, T n+1 Z represents the time interval between the time when the vehicle reaches the predicted distance for the n+1th time and the time when the vehicle reaches the predicted distance for the nth time. nIt represents the time interval smoothing coefficient between the time when the vehicle's previous travel distance reaches (p-β) / γ for the nth time and the time when it reaches (p-β) / γ for the n-1th time, 0<δ<1, δ represents the smoothing constant, according to Z 1 =(1-δ)*T 1 +δ*((T 1 +T 2 +T 3 ) / 3) Calculate the time interval smoothing coefficient Z between the time when the vehicle's previous driving distance reaches (p-β) / γ for the second time and the time when it reaches (p-β) / γ for the first time 1 , according to Z 2 =(1-δ)*T 1 +δ*Z 1 Calculate the time interval smoothing coefficient Z between the time when the vehicle's previous driving distance reaches (p-β) / γ for the third time and the time when it reaches (p-β) / γ for the second time 2 , according to Z 3 =(1-δ)*T 2 +δ*Z 2 Calculate the time interval smoothing coefficient Z between the time when the vehicle's previous driving distance reaches (p-β) / γ for the fourth time and the time when it reaches (p-β) / γ for the third time 3 , and so on to calculate Z n , after the vehicle reaches the predicted distance for the nth time, the interval T n+1 Remind the owner to replace the urea pump filter element;

[0043] By setting a blockage probability threshold and substituting the threshold into the filter maintenance reference model, the vehicle's travel distance when the urea pump filter needs to be replaced is predicted, and the predicted value is used as the condition for triggering the urea pump filter replacement operation. The vehicle's driving pattern is found from the vehicle's historical driving data, and the time when the vehicle's previous driving distance reaches the trigger condition is retrieved to predict the time when the vehicle will need to replace the urea pump filter in the future. The owner is reminded to replace the urea pump filter at the predicted time. The filter replacement time is no longer a fixed cycle, and the replacement time is adaptively and dynamically adjusted with the vehicle's driving conditions, reducing the probability that the urea aqueous solution will generate urea crystals to block the urea nozzle when the vehicle's driving conditions change, thereby affecting the normal purification of the vehicle's exhaust gas and the normal operation of the vehicle.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] When the vehicle's driving distance reaches a certain level, the filter element of the urea pump needs to be replaced in time to reduce the problem of crystallization of urea aqueous solution and nozzle blockage caused by untimely replacement of the filter element. Taking into account the different urea solutions used in exhaust gas purification, different exhaust gas purification performance, different vehicle driving conditions and other factors, different vehicles may cause blockage problems when their driving distance reaches different values. The historical driving data of the vehicle is collected through big data technology, and the problem of crystallization and nozzle blockage is analyzed at what driving distance the vehicle has reached in the past. The historical blockage probability and driving distance are used as reference data to establish a filter element maintenance reference model, which provides accurate reference data for subsequent judgment of the driving distance of the vehicle when the urea pump filter element needs to be replaced.

[0046] By setting a blockage probability threshold and substituting the threshold into the filter maintenance reference model, the vehicle's travel distance when the urea pump filter needs to be replaced is predicted, and the predicted value is used as the condition for triggering the urea pump filter replacement operation. The vehicle's driving pattern is found from the vehicle's historical driving data, and the time when the vehicle's previous driving distance reaches the trigger condition is retrieved to predict the time when the vehicle will need to replace the urea pump filter in the future. The owner is reminded to replace the urea pump filter at the predicted time. The filter replacement time is no longer a fixed cycle, and the replacement time is adaptively and dynamically adjusted with the vehicle's driving conditions, reducing the probability that the urea aqueous solution will generate urea crystals to block the urea nozzle when the vehicle's driving conditions change, thereby affecting the normal purification of the vehicle's exhaust gas and the normal operation of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a schematic diagram of the structure of a control system for vehicle-mounted exhaust gas purification equipment according to the present invention;

[0048] Figure 2 The present invention is a flow chart of a method for controlling vehicle-mounted exhaust gas purification equipment. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] like Figure 1-2 As shown, the present invention provides the following technical solutions: a vehicle-mounted exhaust gas purification equipment control system, comprising: an exhaust gas purification equipment control module, a reference data analysis module, an equipment maintenance condition setting module and an equipment maintenance management module;

[0051] The output end of the exhaust gas purification equipment control module is connected to the input end of the reference data analysis module, the output end of the reference data analysis module is connected to the input end of the equipment maintenance condition setting module, and the output end of the equipment maintenance condition setting module is connected to the input end of the equipment maintenance management module;

[0052] The exhaust gas purification equipment control module is used to perform vehicle exhaust gas purification control after the vehicle is started;

[0053] The reference data analysis module is used to collect and analyze the historical mileage of the vehicle and the historical data of urea crystallization caused by urea nozzle blockage caused by urea aqueous solution used for exhaust gas purification, and generate a reference model for filter element maintenance of the urea pump;

[0054] The equipment maintenance condition setting module is used to set the conditions for triggering the urea pump filter element replacement operation based on the filter element maintenance reference model;

[0055] The equipment maintenance management module is used to predict the time for filter element replacement operation based on the set conditions, and prompt the owner to perform the replacement operation at the predicted time.

[0056] The exhaust gas purification equipment control module includes a vehicle operation sensing unit and a urea solution use control unit;

[0057] The output end of the vehicle operation sensing unit is connected to the input end of the urea solution use control unit;

[0058] The vehicle operation sensing unit is used to sense the vehicle start signal;

[0059] The urea solution control unit is used to control the urea metering injection device installed on the mixing pipe to spray urea aqueous solution after the exhaust gas comes out of the turbine and enters the exhaust mixing pipe after the vehicle is started. The sprayed urea aqueous solution is used to purify the exhaust gas. Urea undergoes hydrolysis and thermal decomposition reactions at high temperature to generate NH3. NH3 is used to reduce NOX and discharge N2. The excess NH3 is also oxidized to N2, thereby achieving vehicle exhaust purification.

[0060] The reference data analysis module includes an operation data acquisition unit, a congestion information acquisition unit and a reference model establishment unit;

[0061] The input end of the operation data acquisition unit is connected to the output end of the vehicle operation sensing unit, the output end of the operation data acquisition unit is connected to the input end of the congestion information acquisition unit, and the output end of the congestion information acquisition unit is connected to the input end of the reference model establishment unit;

[0062] The operation data collection unit is used to collect the distance data of the vehicle in the past, and collect the distance data of the vehicle when the urea nozzle is blocked due to urea crystallization when the urea pump filter element is replaced in the past;

[0063] The blockage information collection unit is used to collect information on the number of times the urea nozzle was blocked due to urea crystallization when the urea pump filter element was replaced when the vehicle traveled different distances in the past;

[0064] The reference model building unit is used to analyze the probability of urea nozzle blockage caused by urea crystallization when the vehicle travels different distances, generate data points based on the driving distance and probability, and establish a filter element maintenance reference model after linear fitting of the data points.

[0065] The equipment maintenance condition setting module includes a critical data input unit and a trigger condition setting unit;

[0066] The input end of the critical data input unit is connected to the output end of the reference model establishment unit, and the output end of the critical data input unit is connected to the input end of the trigger condition setting unit;

[0067] The critical data input unit is used to set the blockage probability threshold value, and substitute the blockage probability threshold value into the filter element maintenance reference model to predict the distance traveled by the vehicle when the urea pump filter element needs to be replaced. The predicted distance means that if the urea pump filter element is not replaced after the vehicle has traveled the corresponding distance, the urea nozzle is likely to be blocked;

[0068] The trigger condition setting unit is used to set the prediction result as a condition for triggering the urea pump filter element replacement operation.

[0069] The equipment maintenance management module includes a replacement time adjustment unit and a filter element replacement reminder unit;

[0070] The input end of the replacement time adjustment unit is connected to the output end of the trigger condition setting unit, and the output end of the replacement time adjustment unit is connected to the input end of the filter element replacement prompt unit;

[0071] The replacement time adjustment unit is used to retrieve the time when the vehicle has traveled to the predicted distance in the past, and predict the time when the vehicle will travel to the predicted distance next time based on the retrieved data;

[0072] The filter element replacement reminder unit is used to remind the vehicle owner to replace the urea pump filter element at the predicted time.

[0073] A method for controlling a vehicle-mounted exhaust gas purification device comprises the following steps:

[0074] S01: Perform vehicle exhaust gas purification control after the vehicle is started: After the vehicle is started, the exhaust gas enters the exhaust mixing pipe after exiting the turbine, and the urea metering injection device installed on the mixing pipe is controlled to inject urea aqueous solution, and the injected urea aqueous solution is used to purify the exhaust gas;

[0075] S02: Collect and analyze the historical mileage of the vehicle and the historical data of urea crystallization and urea nozzle blockage caused by urea aqueous solution used for exhaust gas purification, and generate a reference model for urea pump filter maintenance: The mileage set of the vehicle that has traveled when urea crystallization caused urea nozzle blockage when the urea pump filter was replaced in the past is D={D 1 , D 2 , …, D i , …, D m}, urea nozzle refers to the nozzle of the urea metering injection device, where m represents the number of distance items. When the vehicle travels to the distance in the set D, the number of times the urea nozzle is blocked by urea crystallization when the urea pump filter is replaced is F={F 1 , F 2 , …, F i , …, F m}, F i Indicates that the vehicle travels a distance of D i The number of times the urea nozzle is found to be blocked is calculated according to the formula R i =F i / ∑ m i=1 (F i ) Calculate the vehicle's travel distance to D i The probability R that urea crystals will cause urea nozzle blockage i The probability set of urea crystallization causing urea nozzle blockage when the vehicle travels to different distances is calculated as R={R 1 , R 2 , …, R i , …, R m}, generate data points {(D 1 , R 1 ), (D 2 , R 2 ),…,(D i , R i ),…,(D m , R m )}, and then a filter element maintenance reference model is established by performing a straight line fitting on the generated data points:

[0076] y=γ*x+β;

[0077] Where * represents the multiplication sign, γ and β represent the fitting coefficients, γ=[m∑ m i=1 (D i *R i )-∑ m i=1 (D i )∑ m i=1 (R i )] / [m∑m i=1 (D i ) 2 -(∑ m i=1 (D i )) 2 ],β=[∑ m i=1 (R i )- γ*∑ m i=1 (D i )] / m, x represents the independent variable referring to the vehicle driving distance in the filter element maintenance reference model, and y represents the dependent variable referring to the probability of urea nozzle blockage in the filter element maintenance reference model;

[0078] S03: Setting the conditions for triggering the urea pump filter element replacement operation according to the filter element maintenance reference model: Setting the blockage probability threshold to p, substituting the blockage probability threshold into the filter element maintenance reference model: Let y=p, and predicting that the vehicle travel distance when the urea pump filter element needs to be replaced is: (p-β) / γ, and setting the condition for triggering the urea pump filter element replacement operation to: the vehicle travel distance reaches (p-β) / γ;

[0079] S04: Predict the time for filter element replacement according to the set conditions, and prompt the owner to perform the replacement operation at the predicted time: retrieve the time interval set when the vehicle's previous driving distance reaches (p-β) / γ as T={T 1 , T 2 , …, T n}, where T 1 T represents the time interval between the time when the vehicle's previous driving distance reaches (p-β) / γ for the second time and the time when it reaches (p-β) / γ for the first time, n It represents the time interval between the time when the vehicle's previous driving distance reaches (p-β) / γ for the nth time and the time when it reaches (p-β) / γ for the n-1th time. The time when the driving distance reaches (p-β) / γ for the nth time is the time when the driving distance reaches (p-β) / γ most recently before the current time. The time when the vehicle reaches the predicted distance for the n+1th time is predicted according to the following formula:

[0080] T n+1 =(1-δ)*T n +δ*Z n ;

[0081] Among them, T n+1 Z represents the time interval between the time when the vehicle reaches the predicted distance for the n+1th time and the time when the vehicle reaches the predicted distance for the nth time. nIt represents the time interval smoothing coefficient between the time when the vehicle's previous travel distance reaches (p-β) / γ for the nth time and the time when it reaches (p-β) / γ for the n-1th time, 0<δ<1, δ represents the smoothing constant, according to Z 1 =(1-δ)*T 1 +δ*((T 1 +T 2 +T 3 ) / 3) Calculate the time interval smoothing coefficient Z between the time when the vehicle's previous driving distance reaches (p-β) / γ for the second time and the time when it reaches (p-β) / γ for the first time 1 , according to Z 2 =(1-δ)*T 1 +δ*Z 1 Calculate the time interval smoothing coefficient Z between the time when the vehicle's previous driving distance reaches (p-β) / γ for the third time and the time when it reaches (p-β) / γ for the second time 2 , according to Z 3 =(1-δ)*T 2 +δ*Z 2 Calculate the time interval smoothing coefficient Z between the time when the vehicle's previous driving distance reaches (p-β) / γ for the fourth time and the time when it reaches (p-β) / γ for the third time 3 , and so on to calculate Z n , after the vehicle reaches the predicted distance for the nth time, the interval T n+1 Remind the owner to replace the urea pump filter element.

[0082] Example 1: Establish a filter element maintenance reference model: y=0.085x+0.415, set the blockage probability threshold to p=0.7, and substitute the blockage probability threshold into the filter element maintenance reference model: let y=p=0.7, and predict that the vehicle's mileage when the urea pump filter element needs to be replaced is: (p-β) / γ≈3.35, and the condition for triggering the urea pump filter element replacement operation is set to: the vehicle's mileage reaches 33,500 kilometers.

[0083] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and range of equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for controlling vehicle exhaust gas purification equipment, characterized in that: The following steps are involved: S01: Perform vehicle exhaust purification control after the vehicle is started; S02: Collect and analyze the historical mileage of the vehicle and the historical data of urea nozzle blockage caused by urea crystals formed by urea aqueous solution used for exhaust gas purification, and generate a reference model for filter element maintenance of the urea pump; S03: Setting the conditions for triggering the urea pump filter element replacement operation according to the filter element maintenance reference model; S04: predicting the time for filter element replacement operation according to the set conditions, and prompting the vehicle owner to perform the replacement operation at the predicted time; In step S02: the distance set of the vehicle traveled when the urea nozzle was blocked due to urea crystallization when the urea pump filter was replaced in the past is collected as D={D1, D2, ..., D i , …, D m }, where m represents the number of distance items. When the distances in the set D are collected, the number of times the urea nozzle is blocked by urea crystallization when the urea pump filter is replaced is F={F1, F2, …, F i , …, F m }, F i Indicates that the vehicle travels a distance of D i The number of times the urea nozzle is found to be blocked is calculated according to the formula R i =F i / ∑ m i=1 (F i ) Calculate the vehicle's travel distance to D i The probability R that urea crystals will cause urea nozzle blockage i , the probability set of urea crystallization causing urea nozzle blockage when the vehicle travels to different distances is calculated as R={R1, R2, …, R i , …, R m }, generate data points {(D1, R1), (D2, R2), …, (D i , R i ),…,(D m , R m )}, and then a filter element maintenance reference model is established by performing a straight line fitting on the generated data points: y=γ*x+β; Among them, γ and β represent the fitting coefficients, x represents the independent variable referring to the vehicle driving distance in the filter element maintenance reference model, and y represents the dependent variable referring to the probability of urea nozzle blockage in the filter element maintenance reference model.

2. The vehicle-mounted exhaust gas purification equipment control method according to claim 1, characterized in that: In step S01: after the vehicle is started, the exhaust gas comes out of the turbine and enters the exhaust mixing pipe, and the urea metering injection device installed on the mixing pipe is controlled to inject urea aqueous solution, and the injected urea aqueous solution is used to purify the exhaust gas.

3. The vehicle-mounted exhaust gas purification equipment control method according to claim 1, characterized in that: In step S03: set the blockage probability threshold to p, and substitute the blockage probability threshold into the filter element maintenance reference model: let y=p, and predict that the distance traveled by the vehicle when the urea pump filter element needs to be replaced is: (p-β) / γ, and the condition for triggering the urea pump filter element replacement operation is set to: the vehicle travel distance reaches (p-β) / γ.

4. A vehicle-mounted exhaust gas purification equipment control method according to claim 3, characterized in that: In step S04: retrieve the time interval set of the vehicle's previous travel distance reaching (p-β) / γ as T={T1, T2, ..., T n }, where T1 represents the time interval between the time when the vehicle's previous driving distance reaches (p-β) / γ for the second time and the time when it reaches (p-β) / γ for the first time, T n It represents the time interval between the time when the vehicle's previous driving distance reaches (p-β) / γ for the nth time and the time when it reaches (p-β) / γ for the n-1th time. The time when the vehicle reaches the predicted distance for the n+1th time is predicted according to the following formula: T n+1 =(1-δ)*T n +δ*Z n ; Among them, T n+1 Z represents the time interval between the time when the vehicle reaches the predicted distance for the n+1th time and the time when the vehicle reaches the predicted distance for the nth time. n represents the time interval smoothing coefficient between the time when the vehicle's previous driving distance reaches (p-β) / γ for the nth time and the time when it reaches (p-β) / γ for the n-1th time, 0<δ<1, δ represents the smoothing constant, and the time interval smoothing coefficient Z1 between the time when the vehicle's previous driving distance reaches (p-β) / γ for the second time and the time when it reaches (p-β) / γ for the first time is calculated according to Z1=(1-δ)*T1+δ*((T1+T2+T3) / 3), the time interval smoothing coefficient Z2 between the time when the vehicle's previous driving distance reaches (p-β) / γ for the third time and the time when it reaches (p-β) / γ for the second time is calculated according to Z2=(1-δ)*T1+δ*Z1, the time interval smoothing coefficient Z3 between the time when the vehicle's previous driving distance reaches (p-β) / γ for the fourth time and the time when it reaches (p-β) / γ for the third time is calculated according to Z3=(1-δ)*T2+δ*Z2, and so on to calculate Z n , after the vehicle reaches the predicted distance for the nth time, the interval T n+1 Remind the owner to replace the urea pump filter element.

5. A vehicle-mounted exhaust gas purification equipment control system, applied to a vehicle-mounted exhaust gas purification equipment control method as claimed in claim 1, characterized in that: include: Exhaust gas purification equipment control module, reference data analysis module, equipment maintenance condition setting module and equipment maintenance management module; The output end of the exhaust gas purification equipment control module is connected to the input end of the reference data analysis module, the output end of the reference data analysis module is connected to the input end of the equipment maintenance condition setting module, and the output end of the equipment maintenance condition setting module is connected to the input end of the equipment maintenance management module; The exhaust gas purification equipment control module is used to perform vehicle exhaust gas purification control after the vehicle is started; The reference data analysis module is used to collect and analyze the historical mileage of the vehicle and the historical data of urea crystals formed by the urea aqueous solution used for exhaust gas purification and causing urea nozzle blockage, and generate a filter element maintenance reference model for the urea pump; The equipment maintenance condition setting module is used to set the conditions for triggering the urea pump filter element replacement operation according to the filter element maintenance reference model; The equipment maintenance management module is used to predict the time for filter element replacement operation according to set conditions, and prompt the vehicle owner to perform the replacement operation at the predicted time.

6. The vehicle-mounted exhaust gas purification equipment control system according to claim 5, characterized in that: The exhaust gas purification equipment control module includes a vehicle operation sensing unit and a urea solution use control unit; The output end of the vehicle operation sensing unit is connected to the input end of the urea solution use control unit; The vehicle operation sensing unit is used to sense a vehicle start signal; The urea solution control unit is used to control the urea metering injection device installed on the mixing pipe to spray urea aqueous solution after the vehicle is started and the exhaust gas enters the exhaust mixing pipe after the exhaust gas comes out of the turbine, and uses the sprayed urea aqueous solution to purify the exhaust gas.

7. The vehicle-mounted exhaust gas purification equipment control system according to claim 6, characterized in that: The reference data analysis module includes an operation data acquisition unit, a congestion information acquisition unit and a reference model establishment unit; The input end of the operation data acquisition unit is connected to the output end of the vehicle operation sensing unit, the output end of the operation data acquisition unit is connected to the input end of the congestion information acquisition unit, and the output end of the congestion information acquisition unit is connected to the input end of the reference model establishment unit; The operation data collection unit is used to collect the distance data of the vehicle in the past, and collect the distance data of the vehicle when the urea nozzle is blocked due to urea crystallization when the urea pump filter element is replaced in the past; The blockage information collection unit is used to collect information on the number of times the urea nozzle was blocked due to urea crystallization when the urea pump filter element was replaced when the vehicle traveled different distances in the past; The reference model building unit is used to analyze the probability of urea crystallization causing urea nozzle blockage when the vehicle travels different distances, generate data points based on the travel distance and probability, and establish a filter element maintenance reference model after linear fitting of the data points.

8. The vehicle-mounted exhaust gas purification equipment control system according to claim 7, characterized in that: The equipment maintenance condition setting module includes a critical data input unit and a trigger condition setting unit; The input end of the critical data input unit is connected to the output end of the reference model establishment unit, and the output end of the critical data input unit is connected to the input end of the trigger condition setting unit; The critical data input unit is used to set a blockage probability threshold, substitute the blockage probability threshold into the filter element maintenance reference model, and predict the distance traveled by the vehicle when the urea pump filter element needs to be replaced; The trigger condition setting unit is used to set the prediction result as a condition for triggering the urea pump filter element replacement operation.

9. The vehicle-mounted exhaust gas purification equipment control system according to claim 8, characterized in that: The equipment maintenance management module includes a replacement time adjustment unit and a filter element replacement prompt unit; The input end of the replacement time adjustment unit is connected to the output end of the trigger condition setting unit, and the output end of the replacement time adjustment unit is connected to the input end of the filter element replacement prompt unit; The replacement time adjustment unit is used to retrieve the time when the vehicle has traveled to the predicted distance in the past, and predict the time when the vehicle will travel to the predicted distance next time based on the retrieved data; The filter element replacement reminder unit is used to remind the vehicle owner to replace the urea pump filter element at a predicted time.

Images