US-12623659-B2 - Computer system and a computer-implemented method of controlling the temperature of a selective catalytic reduction system

US12623659B2US 12623659 B2US12623659 B2US 12623659B2US-12623659-B2

Abstract

A computer system comprising processing circuitry configured to obtain topographic data containing information about the topography of the road along which a heavy-duty vehicle is currently travelling, the topographic data including information about an upcoming downhill slope; acquire prediction data indicative of the braking requirements for the upcoming downhill slope, the braking requirements including how much brake power and/or brake energy that will be needed in the upcoming downhill slope to maintain the speed of the heavy-duty vehicle at or below a selected speed limit of the heavy-duty vehicle throughout the travel in the downhill slope; determine a brake blending combination which allows a Selective Catalytic Reduction System (SCR) of the heavy-duty vehicle to be kept as warm as possible while still fulfilling the braking requirements; and apply the determined brake blending combination to the heavy-duty vehicle while travelling along the downhill slope.

Inventors

Martin Wilhelmsson
Oscar STJERNBERG
Anders Eriksson
Erik JONSSON HOLM

Assignees

VOLVO TRUCK CORPORATION

Dates

Publication Date: 20260512
Application Date: 20240828
Priority Date: 20230905

Claims (11)

1 . A computer system comprising processing circuitry configured to: obtain topographic data containing information about topography of a road along which a heavy-duty vehicle is currently travelling, the topographic data including information about an upcoming downhill slope; acquire prediction data indicative of braking requirements for the upcoming downhill slope, the braking requirements including how much brake power and/or brake energy will be needed in the upcoming downhill slope to maintain speed of the heavy-duty vehicle at or below a selected speed limit of the heavy-duty vehicle throughout travel in the downhill slope; determine effects of each of a plurality of brakes on the brake power and at least one of exhaust gas temperature or resulting temperature of a Selective Catalytic Reduction System (SCR), the plurality of brakes comprising service brakes and a plurality of auxiliary brakes; determine, using a brake blending model, a brake blending combination of the plurality of brakes which allows the SCR of the heavy-duty vehicle to be kept as warm as possible while still fulfilling the braking requirements, the brake blending combination including a concurrent brake blending of the service brakes and a plurality of different types of auxiliary brakes; determine a current temperature of the SCR or an expected temperature of the SCR in the upcoming downhill slope is below a predefined threshold temperature; and upon determining that the determined current or expected temperature of the SCR is below the predefined threshold temperature, apply the determined brake blending combination to the heavy-duty vehicle while travelling along the downhill slope.
2 . The computer system of claim 1 , wherein the plurality of auxiliary brakes comprises a retarder, exhaust brake, and/or engine brake.
3 . The computer system of claim 1 , wherein the processing circuitry is further configured to upshift gears for the travel along the downhill slope in addition to applying the determined brake blending combination.
4 . The computer system of claim 1 , wherein the brake blending model implements cost functions where the control target is to minimize the cost.
5 . The computer system of claim 1 , wherein the brake blending model is stored in a remote server which is accessible by the heavy-duty vehicle.
6 . The computer system of claim 1 , wherein the brake blending model is stored in the processing circuitry, onboard the heavy-duty vehicle, wherein the brake blending model is uploadable to a remote server, enabling sharing of the brake blending model with other heavy-duty vehicles.
7 . The computer system of claim 1 , wherein the processing circuitry is further configured to: access stored historical control data representing previous control actions by the processing circuitry; and determine the brake blending combination based on the accessed stored historical control data.
8 . The computer system of claim 7 , wherein the historical data includes information acquired during different brake events of the heavy-duty vehicle and/or information acquired during different brake events of one or more other heavy-duty vehicles, the acquired information including information about the change in temperature of the SCR during the different brake events and different combinations of brake blending.
9 . A heavy-duty vehicle comprising the computer system of claim 1 .
10 . A computer-implemented method of controlling, for a heavy-duty vehicle traveling along a road, a temperature of a Selective Catalytic Reduction System (SCR) which forms part of an Exhaust After-Treatment System (EATS) of the heavy-duty vehicle, the method comprising: obtaining, by processing circuitry of a computer system, topographic data containing information about topography of the road along which the heavy-duty vehicle is currently travelling, the topographic data including information about an upcoming downhill slope; acquiring, by the processing circuitry, prediction data indicative of braking requirements for the upcoming downhill slope, the braking requirements including how much brake power and/or brake energy will be needed in the upcoming downhill slope to maintain speed of the heavy-duty vehicle at or below a selected speed limit of the heavy-duty vehicle throughout travel in the downhill slope; determining, by the processing circuitry, effects of each of a plurality of brakes on brake power and at least one of exhaust gas temperature or resulting temperature of the SCR, the plurality of brakes comprising service brakes and a plurality of auxiliary brakes; determining, by the processing circuitry using a brake blending model, a brake blending combination of the plurality of brakes which allows the SCR to be kept as warm as possible while still fulfilling the braking requirements, the brake blending combination including a concurrent brake blending of the service brakes and a plurality of different types of auxiliary brakes; determining, by the processing circuitry, a current temperature of the SCR or an expected temperature of the SCR in the upcoming downhill slope is below a predefined threshold temperature; and upon determining that the determined current or expected temperature of the SCR is below the predefined threshold temperature, apply the determined brake blending combination to the heavy-duty vehicle while travelling along the downhill slope.
11 . A non-transitory computer-readable storage medium comprising instructions, which when executed by the processing circuitry, cause the processing circuitry to perform the method of claim 10 .

Description

PRIORITY APPLICATIONS The present application claims priority to European Patent Application No. 23195472.8, filed on Sep. 5, 2023, and entitled “COMPUTER SYSTEM AND A COMPUTER-IMPLEMENTED METHOD OF CONTROLLING THE TEMPERATURE OF A SELECTIVE CATALYTIC REDUCTION SYSTEM,” which is incorporated herein by reference in its entirety. TECHNICAL FIELD The disclosure relates generally to a computer system and to a heavy-duty vehicle comprising such a computer system. The disclosure also relates generally to a computer-implemented method. In particular aspects, the disclosure relates to a computer system and a computer-implemented method of controlling the temperature of a selective catalytic reduction system. The disclosure can be applied to heavy-duty vehicles, such as trucks, buses, and construction equipment, among other vehicle types. Although the disclosure may be described with respect to a particular vehicle, the disclosure is not restricted to any particular vehicle. BACKGROUND For heavy-duty vehicles propelled by an internal combustion engine (ICE) it is important to have a high temperature in the exhaust after treatment system (EATS) in order to maintain low emissions of NOx, in line with legal requirements and a general desire to protect the environment. In order to enable efficient conversion of NOx into nitrogen and water, a combination of sufficient heat energy in the selective catalytic reduction system (SCR) and urea is used. Normally, the SCR is heated through the heat energy of the exhaust gases from the ICE and is able to maintain a sufficient temperature during driving. However, there are situations where the heat energy in the exhaust gases may not be sufficient to maintain a desired high temperature of the SCR to enable efficient NOx conversion. One such example may be during downhill driving. During such situations, the SCR cools down by the exhaust gases since the exhaust gases do not contain high enough heat energy. SUMMARY According to a first aspect of the disclosure, there is provided a computer system comprising processing circuitry configured to: obtain topographic data containing information about the topography of the road along which a heavy-duty vehicle is currently travelling, the topographic data including information about an upcoming downhill slope,acquire prediction data indicative of the braking requirements for said upcoming downhill slope, said braking requirements including how much brake power and/or brake energy that will be needed in said upcoming downhill slope to maintain the speed of the heavy-duty vehicle at or below a selected speed limit of the heavy-duty vehicle throughout the travel in the downhill slope,determine a brake blending combination which allows a Selective Catalytic Reduction System, SCR, of the heavy-duty vehicle to be kept as warm as possible while still fulfilling said braking requirements, andapply said determined brake blending combination to the heavy-duty vehicle while travelling along the downhill slope. The first aspect of the disclosure may seek to overcome the problem of NOx emissions due to low temperature of the SCR during downhill driving of a heavy-duty vehicle. A technical benefit may include that by predicting the braking requirements that will be needed for an upcoming downhill slope, the selection of how the braking is applied may be made in such way that a high temperature of the SCR is maintained. Hereby, the risk of high NOx emissions is reduced without compromising the safety when travelling along the downhill slop. The required braking power may be applied to avoid too high speed, but is suitably selected to also maintain a high temperature of the SCR. A heavy-duty vehicle is normally equipped with several braking systems, thus presenting different brake options for the processing circuitry as regards which one or which ones to apply. For instance, a heavy-duty vehicle may comprise service brakes, retarders, exhaust brakes, engine brakes, etc. The processing circuitry may thus select a suitable contribution by each available brake option in order to fulfil a total braking requirement. For instance, if there are four different brake options, the processing circuitry may determine to only use two of the brake options, for example applying 50% of the required brake power from each of the two selected brake options. Other contributions than 50-50 are, of course, also conceivable. In fact, the processing circuitry may decide to do a brake blending combination using 100% of one brake option, and 0% of all the other brake options. Thus, the selected brake blending combination may be any suitable contribution of the different brake options that are available and selectable by the processing circuitry, including zero contribution from one or more of the available brake options. The brake blending combination could, for example, be expressed as: BP=k1⁢P1+k2⁢P2+…+kn⁢Pnwhere BP is the total brake power required in the upcoming downhill slop