Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/0002—Controlling intake air
  • F02D41/0007—Controlling intake air for control of turbo-charged or super-charged engines
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
  • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
  • B60W10/04—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units
  • B60W10/06—Conjoint control of vehicle sub-units of different type or different function including control of propulsion units including control of combustion engines
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
  • B60W10/00—Conjoint control of vehicle sub-units of different type or different function
  • B60W10/10—Conjoint control of vehicle sub-units of different type or different function including control of change-speed gearings
  • B60W10/11—Stepped gearings
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60W—CONJOINT CONTROL OF VEHICLE SUB-UNITS OF DIFFERENT TYPE OR DIFFERENT FUNCTION; CONTROL SYSTEMS SPECIALLY ADAPTED FOR HYBRID VEHICLES; ROAD VEHICLE DRIVE CONTROL SYSTEMS FOR PURPOSES NOT RELATED TO THE CONTROL OF A PARTICULAR SUB-UNIT
  • B60W30/00—Purposes of road vehicle drive control systems not related to the control of a particular sub-unit, e.g. of systems using conjoint control of vehicle sub-units
  • B60W30/18—Propelling the vehicle
  • B60W30/19—Improvement of gear change, e.g. by synchronisation or smoothing gear shift
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D21/00—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas
  • F02D21/06—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air
  • F02D21/08—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D23/00—Controlling engines characterised by their being supercharged
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D31/00—Use of speed-sensing governors to control combustion engines, not otherwise provided for
  • F02D31/001—Electric control of rotation speed
  • F02D31/002—Electric control of rotation speed controlling air supply
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/021—Introducing corrections for particular conditions exterior to the engine
  • F02D41/0215—Introducing corrections for particular conditions exterior to the engine in relation with elements of the transmission
  • F02D41/023—Introducing corrections for particular conditions exterior to the engine in relation with elements of the transmission in relation with the gear ratio shifting
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D9/00—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits
  • F02D9/02—Controlling engines by throttling air or fuel-and-air induction conduits or exhaust conduits concerning induction conduits
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
  • F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
  • F02M26/02—EGR systems specially adapted for supercharged engines
  • F02M26/09—Constructional details, e.g. structural combinations of EGR systems and supercharger systems; Arrangement of the EGR and supercharger systems with respect to the engine
  • F02M26/10—Constructional details, e.g. structural combinations of EGR systems and supercharger systems; Arrangement of the EGR and supercharger systems with respect to the engine having means to increase the pressure difference between the exhaust and intake system, e.g. venturis, variable geometry turbines, check valves using pressure pulsations or throttles in the air intake or exhaust system
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/0002—Controlling intake air
  • F02D2041/0022—Controlling intake air for diesel engines by throttle control
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16H—GEARING
  • F16H63/00—Control outputs from the control unit to change-speed- or reversing-gearings for conveying rotary motion or to other devices than the final output mechanism
  • F16H63/40—Control outputs from the control unit to change-speed- or reversing-gearings for conveying rotary motion or to other devices than the final output mechanism comprising signals other than signals for actuating the final output mechanisms
  • F16H63/50—Signals to an engine or motor
  • F16H63/502—Signals to an engine or motor for smoothing gear shifts
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
  • Y02T10/00—Road transport of goods or passengers
  • Y02T10/10—Internal combustion engine [ICE] based vehicles
  • Y02T10/12—Improving ICE efficiencies

Definitions

• the present invention concerns a method for controlling an element in an engine system.
• the invention further concerns a computer program, a computer program product, a system and a motor vehicle containing such a system.
• Figure 1 shows a situation in which an upshift is occurring from a first (lower) gear G to a second higher gear G 2 (in this case from gear 10 to gear 12).
• the driver is keeping the gas pedal depressed during the entire upshift.
• the upshift occurs as follows:
• the upshift is initiated either manually or automatically, depending upon the transmission system, whereupon the engine torque is reduced so that zero engine torque is received in the transmission;
• engine torque can subsequently be increased so that it corresponds to a desired engine torque.
• An engine rpm reduction normally occurs in that the engine system stops injecting fuel into the engine, which causes the internal friction and pumping work of the engine to retard the engine so that the current engine rpm ⁇ is reduced.
• the pumping work of any engine also referred to as pumping losses, is the work that is needed to pump air into the engine cylinder(s) before ignition, and to pump combusted gas out of the cyiinder(s) after combustion. This means that greater pumping work leads to a more rapid decrease in the engine rpm co , while less pumping work results in a slower reduction in the engine rpm ⁇ , all other factors being equal.
• an exhaust cutout is usually arranged in an exhaust pipe through which exhaust is being conducted out.
• the exhaust cutout is closed/shut off, which results in the build-up of a high exhaust pressure that results in increased pumping work in the engine.
• a variable turbo also known as a VGT (Variable Geometry Turbocliarger)
• VGT Variable Geometry Turbocliarger
• the VGT can, for example, control how much exhaust flow encounters the turbine blades.
• One object of the present invention is to provide a solution that wholly or partly resolves the problem and/or disadvantages of known solutions for controlling an element arranged so as to control a gas pressure in an intake system.
• Another object of the present invention is to provide a solution that enables more efficient utilization of an air reservoir in an air intake system of an engine system.
• the aforementioned objects are achieved by means of a method for controlling an element in an engine system, which system comprises a combustion engine that is connected to an air intake system and an exhaust system and is further mechanically connected to a transmission, and which element is arranged in said air intake system, whereupon said element is controlled based on at least one first parameter , which first parameter ? is related to a gas pressure upstream of said element in said air
• control device connected to said element and arranged so as to control said element; wherein said control device comprises: a receiving unit arranged so as to receive at least one first parameter that is related to a gas pressure E upstream of said element in said air intake system, and
• control unit arranged to control said element based on said at least one first parameter
• the aforesaid system is preferably arranged in a motor vehicle, such as a bus, goods vehicle or another similar motor vehicle.
• a motor vehicle such as a bus, goods vehicle or another similar motor vehicle.
• the system can further be modified so that embodiments of the system correspond, following appropriate changes, to the various embodiments of the method according to the invention,
• A. method and a system according to the present invention provide a solution that makes it possible, among other things, for available air/gas in an air intake system to be used in an efficient, precise and controlled manner, As a result, good engine torque response can be obtained in connection with downshifting and upshifting. Furthermore, the present invention can be used to improve the function of exhaust post-processing and other aspects related to combustion and exhaust purification in engine systems.
• Figure 1 schematically shows engine rpm and engine torque for an upshift
• Figure 2 schematically shows an engine system
• FIG. 3 schematically shows a time diagram of an upshift
• Figure 4 schematically shows a time diagram of a downshift
• Figure 5 shows an example of a control device.
• FIG. 2 shows an exemplified engine system comprising an air intake system connected to a combustion engine 10, e.g. a diesel engine.
• the air intake system consists of an air intake through which air is drawn in and conveyed via one or a plurality of pipes and, in this case a charge air cooler 50, to one or a plurality of cylinders of the engine 10 for combustion with supplied fuel, such as gasoline or diesel.
• a throttle butterfly valve is also disposed in the air intake system between the charge air cooler and the engine cylinders, and the air intake system may also include air-cleaning components,
• the function of the air intake system is to supply air for combustion in the engine cylinder(s).
• An exhaust gas recirculation (EGR) system can also be connected to the air intake system.
• EGR exhaust gas recirculation
• Exhaust gas recirculation is achieved in that exhaust gases are conducted back to the intake side, and the EGR loop usually has an EGR butterfly valve for this purpose; see Figure 2,
• the EGR is used primarily to thin the air for combustion and reduce the proportion of oxygen in the gas that is to be combusted. The combustion temperature is thereby lowered, and NGx formation is inhibited.
• the function of the throttle butterfly valve is to control the gas pressure in the air intake system.
• the throttle butterfly valve is usually of the plate type.
• the throttle butterfly valve is usually controlled by a control unit by means of one or plurality of control elements so that the flow through the intake pipe is controlled based on the desired amount of air in the cylinders.
• the amount of air (the air flow) in the engine is limited by means of a throttle butterfly valve, the gas pressure in the intake pipe will be reduced and, conversely, the gas pressure in the intake pipe will increase if the amount of air in the engine is increased, all other factors being equal .
• Throttle butterfly valves and other types of butterfly valves are usually controlled by means of one or a plurality of control elements, which can be operated pneumatically, hydraulically or by means of electric motors.
• throttle butterfly valves are arranged so as to assume various positions in the pipe with varying velocity v , as the position of the throttle butterfly valve will often track the engine rpm ⁇ so that the through-flow of air in the engine will be adapted to the desired combustion in the cylinders, although the engine load also affects the position of the throttle butterfly valve.
• the system in Figure 2 also comprises a turbo system that has a compressor 61 that is mechanically connected to a turbo turbine 62 via a shaft.
• the air that is drawn into the engine system is compressed in the compressor and then cooled down in the charge air cooler before it passes through the throttle butterfly valve to be conducted into the cylinders via the intake pipe.
• the exhaust gases from the combustion process in the cylinders are conducted through the turbo turbine, which imparts speed to the turbo compressor via the shaft, and the exhaust gases are then conducted out of the engine system via an exhaust system that can comprise, for example, an exhaust collector with an exhaust cutout (not shown) that controls the pressure in the exhaust collector.
• the exhaust gases then pass through a post-processing system, which can comprise a particle filter (DPF, diesel particle filter), a so-called SCR catalytic converter (SCR - Selective Catalytic Reduction), a so-called DOC (DOC - Diesel Oxidation Catalyst) and/or some other form of post-processing components, if such a postprocessing system is included in the engine system.
• the post-processing components are not shown in Figure 2.
• the engine is further mechanically connected to a transmission (not shown), e.g. via a clutch device that can consist of an automatically controlled clutch and is controlled by the vehicle control systems via a control unit, which can also control the transmission.
• the transmission is usually of the manual transmission; automated transmission, such as an automatic transmission, automatic manual transmission (AMT), double clutch transmission (DO j or continuously variable transmission/infinitely variable transmission (CVT/JVT) type.
• One method according to the present invention entails that an element 40 arranged so as to control a gas pressure in an intake system for a combustion engine is controlled based on one or a plurality of first parameters The one or a plurality of first parameters is/are related
• a gas pressure upstream of the element 40 in the air intake system e.g. in a charge air cooler or in a pipe that connects an air intake to an intake pipe to the engine cylinders.
• the invention thus provides a solution that enables efficient, precise and controlled use of the amount of air/gas that is available to the air intake system, as the element 40 is controlled based on one or a plurality of first parameters related to the gas pressure ⁇ $ ⁇ upstream of the element 40.
• the relationship between the amount of air/gas and the gas pressure is easily derived from the general gas law, which describes the relationships between pressure, volume, temperature and substance amount.
• One area of application for the present invention is, for example, to limit undesirable particle build-up in a post-processing system that comprises a particle filter that is arranged so as to capture a portion of the particles in exhaust gases. These particles are stored in the postprocessing system, which can lead to degraded efficiency and increased pressure drop across the post-processing system, which leads in turn to increased fuel consumption and a greater need for regeneration.
• Using an elevated gas pressure during a gas pedal depression (not
• Another preferred area of application for the present invention is in connection with upshifting or downshifting in a transmission, as the invention also provides a solution that enables a built-up air pressure in the intake system to be used efficiently to achieve a good torque response in connection with the engagement of the other gear in a do wnshift or upshift.
• the area of application it is, according to another preferred embodiment of the invention, also suitable for other elements for controlling the gas flow to be controlled based on the first parameter P in order to use the air in the intake system even more efficiently. Examples of such elements commonly found in motor vehicles include VGT and EGR butterfly valves.
• the first parameter i is related to the gas pressure s upstream of the element is to be understand to mean that the first parameter i may be identical to the actual gas pressure 3 ⁇ 4 upstream of the element 40 in the air intake system but also have a direct or indirect correlation with said gas pressure Pm ,
• the first parameter P can be derived as a function of, or have a dependent correlation in some other w r ay with, one or a plurality of gas pressure values upstream of the element.
• the function or correlation can comprise constants, coefficients or other mathematical expressions.
• the function or correlation may further assume discrete, logical or continuous values, depending on the application.
• One way to obtain a direct value for the first parameter P is through the use of one or a plurality of pressure sensors/transmitters in the air intake system upstream of the element 40. This is a straightforward approach that yields rapid and precise values for the first parameter . However, specific hardware in the form of, for example, sensors and signals for signal transmission is necessary. An indirect value for the first parameter ⁇ can also be obtained by using sensors/transmitters.
• Another way of obtaining a value for the first parameter is through the use of a model for the gas pressure in the air intake system upstream of the element 40, rather than using pressure sensors.
• the specific hardware described above is then not necessary, but calculating power and memory are required instead, as well as potentially other hardware, such as turbine rpm counters, mass flow transmitters and pressure sensors disposed in locations other than upstream of the element 40.
• the first parameter can, for example, be modeled as the amount of air/gas that is available in the volume that constitutes the air intake system (e.g. pipes and charge air cooler), which can be viewed as a reservoir.
• the extent to which the air/gas in the reservoir will suffice in connection with, for example, a depression of the gas pedal for the second gear can be calculated by means of other additional parameters, such as engine rpm and volumetric efficiency.
• Another way of modeling the gas pressure in the air intake system is to estimate the flow into and out of the charge air cooler in cases where one is installed.
• the charge air cooler is then modeled as both a volume and a flow restriction (it normally consists of a plurality of narrow pipes that lead to a pressure drop).
• the flow restriction entails a pressure drop.
• the pressure therein can be calculated.
• the flow into the charge air cooler can, for example, be obtained by using a compressor model or mass flow transmitter, while the flows from the charge air cooler can be calculated using throttle equations and calculating the flow into the engine.
• the one or a plurality of first parameters ⁇ is/are used, for example, as input parameters in a control algorithm arranged so as to adjust the gas pressure upstream of the element 50 to a desired value.
• the control algorithm can be of many different types and can, for example, be a simple algorithm that considers only the first parameter and utilizes one or a plurality of threshold values (e.g. an upper and a lower threshold value) to determine which control action is to be performed, A more advanced control algorithm also takes one or a plurality of additional parameters into account, as will be described in detail in the description of various embodiments of the invention that follows.
• the element 40 is controlled so that the gas pressure ⁇ upstream of the element is adjusted toward a so-called set-point value e or target value.
• the control algorithm controls the element 40 so that the gas pressure is adjusted toward a specific set-point value .
• This entails a feedback algorithm.
• the value of said set-point value fte can depend upon the desired objective, such as good torque response in connection with a shift of gears, or improved exhaust purification.
• the set-point value fe can also be a function of the time, so that the value is altered during a process such as during the main stages of a shift of gears related to different times; see for example Figures 3 and 4.
• the element 40 arranged so as to adjust a gas pressure in an intake system for a combustion engine is controlled based on one or a plurality of first parameters in connection with an upshift or downshift in a
• Figures 3 and 4 show time diagrams for engine rpm, engine torque, position of the throttle butterfly valve (how opened or closed the throttle butterfly valve is), a gas pressure upstream Pie and a gas pressure downstream of the element 40 during an upshift (Figure 3), and a
• Figure 4 shows an embodiment of the invention in which the engine system comprises a turbo system (a VGT in this case) and a charge air cooler.
• the element 40 for adjusting the gas pressure in the air intake system in this example is a throttle butterfly valve, but it could be any other suitable element with the same or a corresponding function, i.e. that of adjusting the gas pressure in the air intake system.
• the throttle butterfly valve (corresponding to the element 40) can already be brought toward a more closed position during the start process for the upshift, i.e. during a reduction in engine torque in conjunction with the upshift.
• Bringing the throttle butterfly valve to a more closed position results in a pressure drop across the throttle butterfly valve. This results in a lower gas pressure in the intake pipe (downstream of the element 40) than the pressure in the charge air cooler (upstream of the element 40).
• the throttle butterfly valve is controlled so that the gas pressure in the charge air cooler is utilized during the reduction of engine torque in conjunction with the upshift, i.e. the gas pressure upstream of the
• the method according to the invention attempts to essentially keep the pressure as high as possible, or to maintain or increase the pressure therein, as a large volume (reservoir) consisting of pipe and the charge air cooler itself is present between the turbo compressor that is pressurizing the system and the throttle butterfly valve. Maintaining or increasing the gas pressure in this volume causes it to function as an air reservoir whose air volume can be saved for subsequent combustion during the upshift, which results in a very good torque response. If, on the other hand, the gas pressure cannot be maintained or increased, the throttle butterfly valve is controlled so that the gas pressure is kept as high as possible in the charge air cooler, according to another embodiment of the invention.
• the VGT is normally used to adjust the pressure upstream of the element in connection with a shift of gears.
• the VGT (and any EGR butterfly valve) is closed so that a large counterpressure builds up on the exhaust side, which means that when the shifting process reaches timepoint C in Figure 3, the engine rpm will decrease rapidly because of the high counterpressure.
• the disadvantage of this process is that the compressor has not necessarily been operating in its most efficient operating range, with the result that the pressure on the intake side builds up more slowly or even decreases, resulting in poor torque response during the shift.
• the speed of the turbo turbine will decrease, with the result that it will take a long time before the turbo recovers in terms of rpm.
• the control of the throttle butterfly valve can be combined with the control of the VGT (and any EGR butterfly valve) for improved results in terms of the use of the air/gas upstream of the throttle butterfly valve.
• the VGT is also controlled based on the first parameter , according to another embodiment of the invention.
• the VGT and the throttle butterfly valve must be controlled so that the pumping work between the timepoints C and D in Figure 3 is of sufficiently magnitude, while at the same time a high gas pressure must be maintained up until timepoint D.
• Pumping work of sufficient magnitude means that the pumping work is great enough that the engine rpm at least decreases a certain number of revolutions for a given time during the synchronization phase. Typical values can be between 1200-1500 rpm/s to achieve a rapid shift of gears. This is achieved primarily in that the VGT is closed so that a high exhaust counterpressure is produced.
• the VGT is then controlled, for example, toward a certain exhaust counterpressure (such as 6 bars), and the control of the VGT can then begin at timepoint A in Figure 3, as the system knows that an upshift is to occur. In this way the system is able to built up the exhaust counterpressure in a controlled manner until the shifting process comes at timepoint C in Figure 3. At the same time, at timepoint A in Figure 3, the system closes the throttle butterfly valve as much as possible without risking causing any oil carryover.
• a certain exhaust counterpressure such as 6 bars
• the risk of surging must also be managed during the shift of gears.
• the mass flow through the compressor must be reduced, which results in turn in a decrease in the gas pressumre .
• This can be achieved by opening up either the throttle butterfly valve or the VGT, which entails that the VGT can also be controlled based on the first parameter in this case.
• both the throttle butterfly valve and the VGT can be opened in an interworking process, according to another embodiment of the invention.
• the VGT can be controlled toward optimum turbine output rather than prioritizing the pumping work, i.e. the VGT can be controlled so as to create the best possible mass flow from the compressor, thereby increasing the gas pressure Pic .
• the VGT is controlled so that the gas pressure 1 ⁇ 4 upstream of the element is adjusted toward a so-called set-point value Psc or target value.
• the control algorithm controls the VGT so that the gas pressure is adjusted toward a specific set-point value ⁇ .
• the value of said set-point value can depend on the objective, such as good torque response in connection with a shift of gears, or improved exhaust purification.
• the set-point value can also be a function of the time, so that the value is altered during a process, e.g. during the various times stages of a shift of gears.
• the control of the V GT and the element 40 can be coordinated so that both the VGT and the element are controlled in such a way that the gas pressure Pic upstream of the element is adjusted toward the set-point value r .
• the EGR butterfly valve in principle it should always be closed. If good torque response is desired, the air for combustion is not mixed with exhaust gases. On the other hand, the system may be forced to use the EGR during the shift of gears to meet legal requirements regarding exhaust gases.
• the EGR butterfly valve is normally closed as soon as the system understands that a shift of gears is underway. During gas pedal depression, it can happen that the system will open the EGR butterfly valve to reduce the emissions.
• One way of accomplishing this is to control the EGR butterfly valve toward a certain calibrated EGR amount (although the opposite situation wherein the EGR butterfly valve instead adjusts the air amount and the VGT the EGR amount also occurs).
• the throttle butterfly valve is also controlled so that an air gas [sic] flow at the throttle butterfly valve decreases in connection with the decrease in engine torque associated with the disengagement of the first gear &i .
• the throttle butterfly valve is controlled so that the gas flow at the throttle butterfly valve increases in connection with the increase in engine torque associated with the engagement of the second gear , as is shown in Figure 3.
• the throttle butterfly valve is controlled further so that the gas flow at the throttle butterfly valve increases from a time period before the engagement of the second
• the time period assumes a value within the range of 0.01 to 0.50 s, and the values around 0.1 s (0.05-0.30 s) are suitable with respect to response times for existing actuators in motor vehicles.
• Other parameters that affect the value for the time period include how long a time it takes to fill the volume that is present after the element/throttle butterfly valve 40 but before the cylinders. Said time period is thereby used to compensate for the time delay associated with actuators and the aforementioned volumes.
• the advantage of this process is that direct torque response, i.e. with no delay, is achieved.
• the throttle butterfly valve Just before the target engine rpm for the second gear ⁇ is reached, it is further appropriate for the throttle butterfly valve to be opened up, so that the proper amount of air and thus the proper air/fuel mixture is present to enable the engine to maintain zero torque, This will result in an increase in the gas pressure downstream of the throttle butterfly valve and a decrease in the gas pressure upstream of the throttle butterfly valve .
• the engine torque will increase to, for example, the engine torque desired by the driver.
• Increased engine torque entails a greater amount of fuel being injected into the engine cylinders, and thus a need for a greater amount of air in the cylinders.
• the throttle butterfly valve will be adjusted toward maintaining the lambda value that is required.
• the throttle butterfly valve will be brought to an open position (or optionally a fully open position, if necessary) so as not to choke the air supply to the engine. It is understood from the foregoing that certain other conditions (sub-conditions) may be applicable in controlling the element, i.e. that the element may also be controlled taking into account one or a plurality of additional parameters.
• the element 40 is, according to one embodiment, also controlled based on at least one second parameter that is related to lambda ⁇ , i.e. an air/fuel mixture in the one or
• Lambda ⁇ is an accepted term in
• combustion engine theory can be defined as, for example: where is the mass flow of air into the cylinder, is the mass flow of fuel in the cylinder and is a
• the constant % is chosen so that lambda ⁇ 3 ⁇ 4 is 1 in the event that stoichiometric conditions prevail, i.e. the amount of air is precisely sufficient for the amount of fuel that is to be combusted. If lambda ⁇ is less than 1 , then sufficient air is not present for a given amount of fuel that is being injected into the cylinders. If lambda ⁇ is o ver 1, then there is a surplus of air, and more air is present than is needed for the combustion is present.
• lambda & does not suffice for good combustion, but rather lambda typically assumes a value above 1 in a diesel engine for good combustion (lambda ⁇ can be, for example, ca. 1.3 in this case).
• the throttle butterfly valve can, according to another embodiment of the invention, be controlled so that is not opened entirely following the engagement of the second gear, as that would result in the built-up pressure in the charge air cooler being "punctured" and thereby leading to an unnecessary air surplus for the combustion.
• the throttle butterfly valve (and the VGT and/or EGR butterfly valve) are instead controlled so that the built-up pressure in the charge air cooler is supplied to the combustion as needed, in that lambda is kept at the lowest permissible level (lambda ⁇ will consequently assume a value of roughly 1).
• the torque-limiting time during the shift of gears is thereby reduced or eliminated, which is a major advantage.
• this entails that the element 40 is adjusted toward a desired set-point value for lambda . This can occur in order to achieve good torque response in conjunction with a shift of gears, but also in order to improve the combustion and/or exhaust purification in the engine sy stem.
• the element 40 is also controlled based on at least one third parameter ⁇ that is related to a flow through and a pressure drop across a turbo compressor in the engine system. Obviously this applies in the event that the engine system contains a turbo system with such a compressor. It will be well known to one skilled in the art that a turbo system can begin to surge, which is to be avoided.
• the element 40 is thus controlled so that the flow and pressure drop across the compressor 61 are kept at the same level, so that the turbine does not surge.
• the element is also controlled based on at least one fourth parameter that is related to a gas pressure downstream of the element 40.
• step C the first gear ir i has been disengaged and no engine torque is requested, and the throttle butterfly valve is simultaneously brought into an even more closed position so that the pressure in the charge air cooler will be maintained or increased.
• the current engine rpm ⁇ also decreases to a desired target engine rpm for the second gear ⁇ , and a suitable control loop can ensure that such is the case;
• the throttle butterfly valve for the element 40 is controlled in a manner corresponding to that described above for an upshift.
• the engine torque during a downshift never becomes zero, as is shown in Figure 4.
• Another difference is that engine torque must increase during a downshift so that the second gear can be engaged.
• Yet another difference is that the gas flow at the throttle butterfly valve is not increased prior to the engagement of the second gear , but rather during the engagement of the second gear % .
• the throttle butterfly valve can already have been brought to a more closed position in connection with the process of initiating the shift of gears, i.e. during a reduction of engine torque in conjunction with the downshift.
• engine torque is requested so that the engine rpm increases.
• target rpm for the second gear % is reached, zero torque is requested so that the engine will remain at the target rpm so that the second gear % can be engaged.
• the engine torque will be increased to, for example, the torque desired by the driver, and the throttle butterfly vale is subsequently controlled in the same manner as during the upshift.
• a control algorithm for the element can also be based on one or a plurality of the second ⁇ , third and fourth ⁇ parameters as described above in connection with a downshift as well.
• a downshift is initiated in that engine torque is reduced and the throttle butterfly valve is simultaneously caused to assume a more closed position, so that the pressure in the charge air cooler will be maintained or increased;
• the first gear ⁇ is disengaged and a higher engine torque is requested so that the engine rpm will increase, and the throttle butterfly valve is simultaneously controlled so that the pressure in the charge air cooler can be maintained or increased, subject to the condition that a desired value for ⁇ is obtained.
• the current engine rpm ft) also decreases to a desired target engine rpm for the second gear , and a suitable
• control loop can ensure that such is the case
• the current engine rpm is the same as the target engine rpm, and engine torque can be reduced, the second gear ⁇ is engaged and the throttle butterfly valve is controlled toward a desired value for ⁇ ;
• the present method can be implemented in a control system comprising, for example, a control device arranged so as to control all or parts of an engine system in a motor vehicle.
• the control system can further comprise additional control devices arranged so as to control other functions, such as an external load, external heaters, etc.
• Control devices of the type shown are normally adapted so as to receive one or a plurality of sensor signals for various parts of the vehicle, and from other control devices. These control devices are further normally arranged so as to send control signals and/or information signals to various vehicle components and/or other control devices.
• the control devices can also comprise, or be connected to, a calculating unit arranged so as to calculate/simulate the predicted parametric values.
• the control systems in modern motor vehicles normally consist of a communication bus system consisting of one or a plurality of communication buses for connecting a number of electronic control units (ECUs) or controllers, 1 15, 208, and various components arranged in the motor vehicle.
• ECUs electronice control units
• controllers 1 15, 208
• various components arranged in the motor vehicle.
• Such a control system can comprise a large number of control devices, and the responsibility for a specific function in the motor vehicle can be shared among one or a plurality of control devices.
• the control often occurs by means of programmed instructions.
• These programmed instructions typically consist of a computer program which, when it is executed in a computer or control unit, causes the computer/control unit to perform the desired control method, such as methods according to the present invention.
• the computer program usually constitutes a part of a computer program product, wherein said computer program product comprises a suitable storage digital non-volatile/permanent/lasting/durable storage medium 121 on which the computer program is stored.
• Said digital digital [sic] non- volatile/permanent/lasting/durable storage medium 121 consists of a suitable memory, such as: ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), fi'ROM (Erasable PROM), Flash memory, EEPROM (Electrically Erasable PROM), a hard disk unit etc, and is arranged in or in connection with the control unit, whereupon the computer program is executed by the control unit.
• control device 208 is shown schematically in Fig. 4, wherein the control device can in turn comprise a calculating unit 120, which can consist of, for example, any suitable type of processor or microcomputer, such as a circuit for digital signal processing (Digital Signal Processor, DSP) or a circuit with a predetermined specific function (Application Specific Integrated Circuit, ASIC).
• the calculating unit 120 is further connected to a memory unit 121, which furnishes the calculating unit 120, with e.g. the stored program code 126 and/or the stored data that the calculating unit 120 requires to be able to perform calculations.
• the calculating unit 120 is also arranged so as to store partial or final results of calculations in the memory unit.
• control device is equipped with elements/devices 122, 123, 124, 125 for receivmg and transmitting input and output signals, respectively.
• These input and output signals can comprise waveforms, pulses or other attributes that the devices for receiving input signals can detect as information for processing by the calculating unit.
• the devices 123, 124 for transmitting output signals are arranged so as to convert calculation results from the calculating unit into output signals for transfer to other parts of the motor vehicle control system and/or the components) for which the signals are intended.
• Each and every one of the connections to the devices for receiving and transmitting respective input and output signals can consist of one or more of a cable; a data bus, such as a CAN (Controller Area Network bus), a MOST (Media Oriented Systems Transport) or any other bus configuration, or of a wired or wireless communication connection.
• a data bus such as a CAN (Controller Area Network bus), a MOST (Media Oriented Systems Transport) or any other bus configuration, or of a wired or wireless communication connection.
• the present invention further concerns a system corresponding to any embodiment of the method according to the invention.
• the system comprises a combustion engine 10 connected to an air intake system and an exhaust system.
• the combustion engine is further mechanically connected to a transmission 30.
• the system further comprises an element 40 that is disposed in the air intake system and arranged so as to adjust the gas pressure in the air intake system.
• the system comprises a control device connected to the element 40 and arranged so as to control the element 40.
• the control element in this case comprises a receiving unit and a control unit.
• the receiving unit is arranged so as to receive at least one first parameter that is related to a gas pressure Ptc upstream of the element 40 in the air intake system.
• control unit is arranged so as to control the element 40 based on the at least one first * p i , for example in connection with an upshift or downshift in the transmission from a first gear &i to a second gear % , o for efficient combustion and/or exhaust purification.
• control device can be a separate control device, a part of another control device that controls one or a plurality of element or units, or part of a larger control system comprising a plurality of control de vices.
• One or a plurality of systems according to the present invention can be disposed in a motor vehicle, such as a bus, goods vehicle or the like.
• the combustion engine of the system is a diesel engine.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Transportation (AREA)
• Automation & Control Theory (AREA)
• Control Of Vehicle Engines Or Engines For Specific Uses (AREA)
• Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
• Control Of Throttle Valves Provided In The Intake System Or In The Exhaust System (AREA)

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Citations (4)

• 2014
  • 2014-01-28 BR BR112015015087A patent/BR112015015087A2/pt not_active Application Discontinuation
  • 2014-01-28 WO PCT/SE2014/050107 patent/WO2014120071A1/en active Application Filing
  • 2014-01-28 SE SE1450078A patent/SE539406C2/sv unknown
  • 2014-01-28 DE DE112014000369.7T patent/DE112014000369T5/de active Pending

Patent Citations (4)

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