Description:Complete Specification:
The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed

Field of the invention
[0001] The present disclosure relates to a control unit to control a regeneration process in an exhaust system
Background of the invention
[0002] The Bharat stage 6 (BS6) emission standards are mandated to be implemented for all class of vehicles in India since 2020. In order to meet the mandate for Particulate matter (PM) and NOx emission targets the exhaust systems for IC engines now mandatorily use the three Way Catalyst, Diesel Oxidation Catalyst (DOC), Diesel Particulate Filter (DPF), Gasoline Particulate Filter (GPF) and SCR (Selective Catalytic Reduction). The particulate matter and soot as carried by the exhaust gas gets deposited in various components such as the DPF and has to be removed over-time.
[0003] To remove the particulate matter in the exhaust components such as the diesel particulate filter (DPF) once it is loaded with excessive ash and soot, a Regeneration process is to be triggered. During the regeneration process, the fuel is injected into the exhaust stream after the main combustion event. The post-combustion injected fuel is combusted over catalysts placed in the exhaust stream. The heat released during the fuel combustion on the catalysts increases the exhaust temperature, which burns the trapped soot particles in the DPF. After Regeneration is triggered and the vehicle is shortly parked, the exhaust O2 concentration may increases. High O2 concentrations in the exhaust stream accelerates the oxidation of the trapped soot, causing the internal temperature in the DPF to increase above a critical value. During DPF (Diesel Particulate Filter) regeneration, it is necessary to maintain temperature of around 600 (approximate) degree Celcius. However, if vehicle is stopped when regeneration is ongoing, it harms the life of components of the exhaust system. Since there is no exhaust flow when engine is stopped, it becomes a heat trap for DPF in exhaust. Further, to reduce the engine temperature, the coolant fan is switched on even after engine is stopped, which makes a constant noise after parking the vehicle.
[0004] The prior art US7275365B2 discloses a method for controlling temperature in a diesel particulate filter during regeneration. Uncontrolled regeneration in a Diesel particulate filter is prevented by controlling the concentration and mass flowrate of oxygen passing through the Diesel particulate filter during regeneration.
[0005] The prior art US8635020 discloses a method for automatically entering favorite locations into a navigation system is provided. The method according to one embodiment includes receiving information regarding a location from an object within a vehicle using a navigation system. An identifier to the information and the information and identifier are stored in the navigation system. The user may retrieve the information from the navigation system using the identifier. The information from the objects may be received in various wireless formats, including RFID, Bluetooth and Wi-Fi.
[0006] To solve the aforementioned problem, the present invention discloses a control unit to control a diesel particulate filter (DPF) regeneration process. If the location of parking of the vehicle is known, then it is possible to interrupt the Regeneration process in advance in order to bring back the DPF and engine temperature to normal level.

Brief description of the accompanying drawings
[0007] An embodiment of the invention is described with reference to the following accompanying drawings:
[0008] Figure 1 depicts a control unit to control a regeneration process in an exhaust system
Detailed description of the drawings

[0009] The present invention will now be described by way of example, with reference to accompanying drawings. Throughout all the figures, same or corresponding elements may generally be indicated by same reference numerals. These depicted embodiments are to be understood as illustrative of the invention and not as limiting in any way. It should also be understood that the figures are not necessarily to scale and that the embodiments are sometimes illustrated by graphic symbols, phantom lines, diagrammatic representations and fragmentary views. In predetermined instances, details which are not necessary for an understanding of the present invention, or which render other details difficult to perceive may have been omitted. Further, the principles and techniques widely known in the art to implement the present disclosure are not described in detail.

[0010] Referring to Figure 1, the same depicts a control unit (1) to control a regeneration process in an exhaust system (3) of a vehicle (10) . The control unit (1) receives a set of POI (4) from a GPS SYSTEM (2) (global position system) of the vehicle (10) . Based on said set of POI (4) , the control unit (1) predicts an event of parking of the vehicle (10) and controls at-least one vehicle (10) parameter to regulate the regeneration process when the event of parking is predicted.

[0011] Further the construction of the control unit (1) and the components connected to the control unit (1) is explained in detail. The control unit (1) is a logic circuitry and software programs implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and/or any component that operates on signals based on operational instructions. Modern day vehicles may contain a plurality of control units like the Transmission control unit, Engine control unit , Vehicle control unit, Steering control unit , exhaust after treatment drive control unit and the like. In an exemplary embodiment of the present invention, the control unit (1) could be any one of a vehicle control unit and an exhaust aftertreatment drive control unit, including a dosing control unit (6).

[0012] According to an embodiment of the present disclosure, the control unit (1) is configured to control or communicate with other vehicular controllers capable of controlling the at least one vehicle parameter. The control unit (1) may communicate with the vehicular controllers through a wired and/or wireless communication method such as CAN bus, Bluetooth and other in vehicle communication technologies known in the art.

[0013] According to an embodiment of the present disclosure, the exhaust system (3) may include exhaust manifolds, exhaust conduits, and exhaust system components including a catalyst, a diesel particulate filter (DPF), a three Way Catalyst, a Diesel Oxidation Catalyst (DOC), Gasoline Particulate Filter (GPF) , SCR (Selective Catalytic Reduction) a heater and such other components known to be present in an exhaust system of a diesel or a gasoline engine. The exhaust manifolds direct the exhaust from an engine combustion in the vehicle (10) into the exhaust conduits. The exhaust is directed into the exhaust system (3) through the exhaust system components such as the DPF filters wherein the particulates from the exhaust stream are removed as it flows to the atmosphere. The exhaust system (3) further comprises a dosing control unit (6) to control an amount of diesel exhaust fluid injected into the exhaust system. According to an example, the controller is in communication with the dosing control unit (6). It is to be understood that the technique described herein can be used for regeneration in the entire exhaust system, including all the exhaust system components. The listing of the said ‘exhaust system components’ is not to be construed as limiting.

[0014] The control unit (1) is in communication with the GPS SYSTEM (2) . The GPS SYSTEM (2) maybe integrated into vehicular navigation device, a portable navigation device, handheld mobiles, cellular telephone, media player with GPS (Global Positioning Systems) capabilities that aid the user in navigating from the origin to the destination by displaying the path between the two locations. According to the present invention, the GPS is integrated into a vehicle (10) and interacts with the user through a display means. The display means may be a human machine interface (HMI) such as an interactive touch screen well known in the art.

[0015] According to the present invention, the GPS SYSTEM (2) comprises a processor configured to identify a set of routes between the origin and the destination. According to an embodiment, the GPS SYSTEM (2) comprising the processor may have an associated memory to store instructions and data, such as a hard disk , a read-only memory (ROM - "Read Only Memory"), a programmable read-only unit and Electrically Erasable (EEPROM - "Electrically Erasable Programmable Read Only Memory") and a random access memory (RAM - "Random Access Memory"). Memory may comprise map data and cartographic. These cartographic data can be cartographic data in two dimensions (latitude and longitude), but which can also comprise a third dimension (altitude). The cartographic data also includes additional information such as information about points of interests (such as petrol station, restaurants, hospitals, police stations and the like.

[0016] The control unit (1) comprises a memory to receive and store the set of POI (4) from the GPS SYSTEM (2) . The set of POI (4) comprises at least one point of interest (POI) identified on a route taken by the vehicle (10) , and at least one slope information of the route taken by the vehicle (10) . It is to be understood that in addition to identification of at least one POI by the GPS SYSTEM (2) , the GPS SYSTEM (2) may identify a set of POI based on a navigation history of the vehicle (10) . This includes identification of locations where the vehicle (10) was parked along a route in the past. In another example, a slope information along a route may also be identified by the GPS SYSTEM (2) (as a part of cartographic data as explained above). This identified set of POI based on navigation history is also communicated to the control unit (1) which (the control unit (1)) then stores the identified set as stored-set (5) of POI. According to an embodiment, these stored set of POI maybe stored in the memory of the control unit (1) or in a cloud memory.

[0017] According to an embodiment of the present disclosure, the at least one POI is identified by mapping the set of POI on the route taken by the vehicle (10) with the stored set of POIs on the route taken by the vehicle (10). Said stored-set (5) of POI stored in the memory of the control unit (1). In an example, the stored set of POIs maybe a home location, an office location, a petrol pump, a parking zone and the like.

[0018] According to another embodiment of the present disclosure, the at least one POI may be identified when a driver of the vehicle (10) inputs the at least one point of interest through a human machine interface. In an example, the driver may be given an option to add/edit more such POIs. In another example, the driver may be informed of the Regeneration control functionality as disclosed in the present invention before it is triggered through a display means in the HMI. In another example, the driver may confirm if the driver is not going to park despite the predicted parking event.

[0019] The control unit (1) predicts an event of parking of the vehicle (10) based on said set of POI (4) . In an example, assuming that the vehicle (10) is navigating through a route from a current location on the route. The control unit (1) will receive the set of POI (4) from the GPS SYSTEM (2) with four POIs A, B, C, D. The stored set of POI are then mapped with the POIs A,B,C,D. If the POI C is a part of the stored set of POI, then an event of parking is predicated. In another example, the control unit (1) may receive as a part of the set of POI (4) an information that the route is/has a downhill slope. In an example, the stored-set of POI may be stored along with a route information. In another example, the stored set of POI may be stored without the route information for an efficient use of memory. The presence or absence of route specific data is not to be construed as limiting the scope of the present invention.

[0020] The control unit (1) controls the at least one vehicle parameter to regulate the the regeneration process when the event of parking is predicted. The at least one vehicle parameter comprises at least of a dosing rate of diesel exhaust fluid into the exhaust system, a fuel injection rate of the vehicle (10) , and a mass flow rate of the exhaust gas flowing into the exhaust system. It is to be understood that the at least one vehicle parameters include all such other vehicle (10) parameters that have an effect on the regeneration process wherein, controlling said vehicle (10) parameters has a direct effect on halting/speeding/stopping/pausing/triggering the regeneration process. It is further to be understood that the control unit (1) is configured to control all such vehicular controllers controlling said at least one vehicle parameter.

[0021] The control unit (1) controls the at least one vehicle parameter based on a distance between a current location of the vehicle (10) and the at least one point of interest. In an example, if the event of parking at a location C is detected, then, based on the distance between the current vehicle (10) location and the location C, the at least one vehicle parameter may be controlled. Thus, the ongoing Regeneration will be interrupted before a predetermined distance/time of reaching the parking location C. When the vehicle (10) is operational, the current location is continuously monitored with respect to the stored-set (5) of POIs (stored location). The GPS SYSTEM (2) distance can be used to determine the proximity to the stored locations. If the vehicle (10) is approaching one of the stored locations (distance reducing) and the current distance is less than the pre-determined distance (e.g.: 1km), then a trigger can be sent out by the control unit (1) to prepare the vehicle (10) for Regeneration control and optimization. When trigger comes, the vehicle (10) needs to be prepared for the Regeneration control associated with the location. For instance, when a “regular parking location” is approaching and Regeneration is in progress, it is necessary to trigger Regeneration control action. In this case, it is to interrupt the ongoing Regeneration before a predetermined distance/time of reaching the regular parking location. Further, based on the number of times the regeneration was interrupted before the parking event, an estimate of the increase in component life (and hence the cost saving) can be stored and communicated to driver/user. Further an amount of AdBlue saved and the amount of ammonia prevented from leaking maybe estimated and can be conveyed in terms of the cost and the percentage reduction of emission.

[0022] According to another embodiment of the present disclosure, control unit (1) controls the dosing rate of DEF (diesel exhaust fluid) based on the slope information of the route taken by the vehicle (10) . In an example, the DEF (also referred to as AdBlue) dosing can be stopped/reduced before a predetermined distance/time of reaching the downhill slope. Advantageously, in addition to Regeneration process control, the same prevents leakage of AdBlue and/or converted/stored Ammonia that might get otherwise leaks into the atmosphere when there is no NOx in the exhaust to convert. The same is prevented if the parking event is predicted and based on that the dosing amount is reduced gradually.
, Claims:We Claim:
1. A control unit (1) to control an exhaust regeneration process in an exhaust system (3) of a vehicle (10) , characterized in that, the control unit (1) configured to:

-receive a set of POI (4) from a GPS SYSTEM (2), said GPS SYSTEM (2) in communication with the control unit (1),
-predict an event of parking of the vehicle (10) based on said set of POI (4) , and
-control at-least one vehicle parameter to regulate the Regeneration process when the event of parking is predicted.

2. The control unit (1) as claimed in Claim 1, wherein, the at least one vehicle parameter comprises at least one of:
-a dosing rate of diesel exhaust fluid into the exhaust system,
-a fuel injection rate of the vehicle (10) , and
-a mass flow rate of the exhaust gas flowing into the exhaust system.

3. The control unit (1) as claimed in Claim 1, wherein the set of POI (4) comprises :
-at least one point of interest identified on a route taken by the vehicle (10) , and
-at least one slope information of the route taken by the vehicle (10) .

4. The control unit (1) as claimed in Claim 2 , wherein, the control unit (1) controls the dosing rate of DEF based on the slope information of the route taken by the vehicle (10) .

5. The control unit (1) as claimed in Claim 2, wherein, the at least one POI is identified by mapping the set of POIs on the route taken by the vehicle (10) with a stored-set (5) of POIs on the route taken by the vehicle (10) , said stored-set (5) of POI stored in a memory of the said control unit (1).

6. The control unit (1) as claimed in Claim 1, wherein, the control unit (1) receives the at least one point of interest from a driver of the vehicle (10) through a Human Machine Interface (HMI).

7. The control unit (1) as claimed in Claim 1, wherein, the control unit (1) controls the at least one vehicle parameter based on a distance between a current location of the vehicle (10) and the at least one point of interest