Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N11/00—Starting of engines by means of electric motors
  • F02N11/08—Circuits or control means specially adapted for starting of engines
  • F02N11/0851—Circuits or control means specially adapted for starting of engines characterised by means for controlling the engagement or disengagement between engine and starter, e.g. meshing of pinion and engine gear
  • F02N11/0855—Circuits or control means specially adapted for starting of engines characterised by means for controlling the engagement or disengagement between engine and starter, e.g. meshing of pinion and engine gear during engine shutdown or after engine stop before start command, e.g. pre-engagement of pinion
• • 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
  • F02D41/009—Electrical control of supply of combustible mixture or its constituents using means for generating position or synchronisation signals
  • F02D2041/0095—Synchronisation of the cylinders during engine shutdown
• • 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
  • F02D41/04—Introducing corrections for particular operating conditions
  • F02D41/042—Introducing corrections for particular operating conditions for stopping the engine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N11/00—Starting of engines by means of electric motors
  • F02N11/08—Circuits or control means specially adapted for starting of engines
  • F02N11/0814—Circuits or control means specially adapted for starting of engines comprising means for controlling automatic idle-start-stop
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N19/00—Starting aids for combustion engines, not otherwise provided for
  • F02N19/005—Aiding engine start by starting from a predetermined position, e.g. pre-positioning or reverse rotation
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2200/00—Parameters used for control of starting apparatus
  • F02N2200/02—Parameters used for control of starting apparatus said parameters being related to the engine
  • F02N2200/022—Engine speed
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2250/00—Problems related to engine starting or engine's starting apparatus
  • F02N2250/04—Reverse rotation of the engine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2300/00—Control related aspects of engine starting
  • F02N2300/10—Control related aspects of engine starting characterised by the control output, i.e. means or parameters used as a control output or target
  • F02N2300/102—Control of the starter motor speed; Control of the engine speed during cranking
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2300/00—Control related aspects of engine starting
  • F02N2300/20—Control related aspects of engine starting characterised by the control method
  • F02N2300/2006—Control related aspects of engine starting characterised by the control method using prediction of future conditions
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02N—STARTING OF COMBUSTION ENGINES; STARTING AIDS FOR SUCH ENGINES, NOT OTHERWISE PROVIDED FOR
  • F02N2300/00—Control related aspects of engine starting
  • F02N2300/20—Control related aspects of engine starting characterised by the control method
  • F02N2300/2008—Control related aspects of engine starting characterised by the control method using a model

Definitions

• the invention relates to a method of a control and a control for a start-stop operation of an internal combustion engine in a motor vehicle for short-term stopping and starting the internal combustion engine, which is started by an electric machine as a starter, wherein by a detection device, the position and the Speed of a crankshaft during operation and after switching off the internal combustion engine, especially at a short-term stop, is detected.
• the invention further relates to a computer program product and a controller having a microcomputer with a program memory.
• the internal combustion engine is started by means of a starter having a starter pinion meshed with a ring gear of an internal combustion engine.
• a starter pinion meshed with a ring gear of an internal combustion engine.
• DE 10 2006 039 112 A1 describes a method for determining the rotational speed of the starter for a motor vehicle internal combustion engine. It is further described that the starter includes its own starter controller to calculate the speed of the starter and to accelerate in a start-stop operation, the pinion from the starter first without meshing when a self-starting of the engine due to decreased speed is no longer is possible. The pinion is engaged at synchronous speed in the ring gear of the expiring internal combustion engine.
• the starting device for an internal combustion engine with a separate engaging and starting operation.
• the starting device has a control unit which controls a starter motor and an actuator for engaging a starter pinion separately. From the control unit, the pinion can be meshed before starting the vehicle in the ring gear before the driver has expressed a new start request.
• the actuator is already actuated as an engagement relay during a coastdown phase of the internal combustion engine.
• the speed threshold is in this case far below the idle speed of the engine to keep the wear of the Einspurvoriques as low as possible.
• the controller is a soft start, for example, achieved by a clocking of the starter current.
• the performance of the vehicle electrical system is monitored by analyzing the state of the battery and accordingly the starter motor is clocked or supplied with power. Furthermore, the invention describes that the crankshaft can be positioned shortly before or after reaching standstill of the internal combustion engine to shorten the start time.
• DE 10 2005 021 227 A1 describes a starting device for an internal combustion engine in motor vehicles with a control unit, a starter relay, a starter pinion and a starter motor for a start-stop operating strategy. It is an object of the present invention, a method, a computer program product and a start-stop control of the type mentioned in such a way to improve vehicle comfort, in which a restart of the engine is much faster executable.
• An underlying idea of the invention is that the speed curve of a crankshaft when switching off the engine is extremely inhomogeneous and therefore a rough averaging leads to a coarse Bremsverzögerungs- value for a meshing a starter pinion of a starter in a ring gear of an internal combustion engine because of a large tolerance band is unfavorable. Therefore, according to one idea of the invention, the speed curve of a decreasing speed of the crankshaft is calculated in each case up-to-date, individually and specifically.
• the object is achieved by a method in that the course of the speed crankshaft after switching off the internal combustion engine is actively and recalculated in advance.
• a high-precision statement about the rotational speed of a ring gear in advance can be calculated, since current environmental conditions, such as temperature and current friction and braking torques in the measurement result and the calculation incorporated.
• Active is thus a current calculation of new measured values, without looking up and deriving forecast values from previously defined characteristics.
• the angular velocity of the crankshaft of the internal combustion engine is detected and calculated at characteristic, in particular recurring, positions of the crankshaft during the outflow of the internal combustion engine.
• This has the advantage that the data quantities to be measured and analyzed, in comparison to an analysis of the entire inhomogeneous velocity course with coarse averaging, are very high are low.
• the external conditions which influence the angular velocity or the angular velocity gradient for example the engine temperature, the engine oil quality, the age of the engine, internal friction moments and additional braking torques by additional units, etc., are advantageously recorded.
• a very specific and much more accurate forecast for the course of the rotational speed of the crankshaft can be achieved, as is conventionally known. So far, it has been known to interrogate values from characteristic curves which are laid down with a rough averaging in the control, for example.
• the angular velocity of the crankshaft is detected and calculated in ignitable top dead centers.
• the fact that the ignitable top dead centers of an internal combustion engine reproduce characteristic speed runs in which the angular speed is somewhat slower for a short time than in the other positions is advantageously adopted in accordance with the method according to the invention.
• the top dead centers (ZOT) can provide reliable data to actually determine a low-volume speed history and make a prognosis on the future crankshaft angular velocity.
• At least two values of the angular velocity of ignitable top dead centers are used to calculate at least one third value for a following, future ignitable top dead center (ZOT 3).
• ZOT angular velocity of ignitable top dead centers
• ZOT 3 future ignitable top dead center
• the speed curve is detected at a high speed with a sampling rate by a sensor device on the internal combustion engine, and the determined values are evaluated to forecast low speeds shortly before standstill.
• a conventional sensor device can be inexpensively used on the crankshaft of the internal combustion engine whose sampling rate is typically limited to 50 to 100 signals per revolution.
• values from a high speed range are taken to values in a low speed range , thus, a future angular velocity can be derived.
• the angular speed of the crankshaft is calculated in advance, determines therefrom a synchronous speed for a running-up starter and then a starter pinion meshed by the starter in an expiring with decreasing speed ring gear of the internal combustion engine at substantially synchronous speed.
• Synchronous meshing means the speed and the time when the speed of the starter pinion and the speed of the ring gear of the internal combustion engine are substantially equal, d. H. the window of a speed difference of starter pinion and ring gear is sufficiently small.
• the speed of the starter pinion is brought to a predetermined Einspurzeittician by driving from a controller, which is designed for a start-stop operation, to the previously calculated speed of the internal combustion engine.
• a controller which is designed for a start-stop operation
• a very accurate synchronous speed of starter pinion and internal combustion engine is achieved.
• the wear thus decreases and the noise is reduced.
• the availability of a restart of the internal combustion engine is given from the Einspurzeittician.
• the angular velocity of the crankshaft with starter pinion meshed in the toothed rim is calculated in advance and the starter is momentarily energized in a dosed manner in dependence on a predicted, anticipated position of a standstill, in order to produce a recovery. Avoid the crankshaft and / or the crankshaft in a favorable motor type specific preferred position, in particular with an angle greater than 60 °, and more preferably about 80 ° to 100 °, most preferably from about 90 °, before the next upper to move ignitable dead center.
• the angle values are only an example and are given here by way of example for eg a 6-cylinder engine.
• the method described above can be used a second time for a start-stop operation to bring the crankshaft to such an optimal angle in the internal combustion engine, in which the internal combustion engine can be started quickly.
• the object is also achieved by a computer program product which can be loaded with program instructions into a program memory in order to execute all the steps of the method described above when the program is executed in a controller.
• the computer program product requires no additional components in the vehicle, but can be implemented as a module in existing controls in the vehicle.
• the computer program product may be provided, for example, in the engine controller, a separate dedicated controller, or a starter controller.
• the computer program product has the further advantage that it can easily be adapted to individual and specific customer requirements, as well as an improvement of the operating strategy by improved empirical values or individually provided values of the vehicle can be easily used.
• the object is also achieved with a controller in that the microcomputer in the controller is designed as a detection, evaluation and control device, wherein in the program memory, a computer program product described above is loadable to carry out a method described above.
• the controller for a start-stop operation may be formed either in a motor controller or in a separate controller, for example in a starter control for controlling a starter or separately from other controllers.
• the controller is in information contact at least with the motor control via a bus system.
• the control is, for example, in the engine control educated.
• the controller is alternatively advantageously housed in the starter control. Both alternatives have the advantage that essential parts of the hardware, which are available for other functions, for example, can be used to carry out the method.
• FIG. 1 is a schematic circuit diagram of drive components for carrying out the method according to the invention
• Fig. 3 is a time-speed diagram at the end of the coasting of an internal combustion engine
• Fig. 4 is a time-speed diagram over a larger period of time.
• Fig. 1 shows a simplified circuit diagram of drive components, for carrying out a start-stop operating strategy.
• An internal combustion engine 1 is formed with a plurality of cylinders 11, 12, 13, 14. Pistons in the cylinders 11 to 14 drive a crankshaft 2.
• a gear 3 is mounted on the crankshaft 2, which typically has 50 to 100 teeth and gaps. At one point on the gear 3, a larger gap is formed as a synchronization mark.
• the sync mark and the tooth gap sequence detek- a sensor 4 and transmits these detected values to the engine controller 5.
• a ring gear 6 is mounted on the crankshaft 2 at the end opposite the gear 3.
• the ring gear 6 is turned on by a starting device 7 when starting the internal combustion engine 1.
• the starting device 7 comprises a starter 8 on the axis of a starter pinion 9 is mounted axially displaceable.
• the starter pinion 9 is by means of a starter relay 10 in the ring gear 6 and disengaged.
• the starting device 7 has a starter control 15.
• the starter control 15 has a microcomputer 16 with a program memory 17. By means of the starter control 15, the starter relay 10 and the starter 8 can be selectively controlled separately.
• the microcomputer 16 also has a timer 18.
• the microcomputer 16 is in motor contact with the motor controller 5 via a bus system, for example via a CAN bus 19, in information contact.
• the engine controller 5 is connected to the information exchange with actuators and sensors of the internal combustion engine 1.
• the sensor 4 is in information contact with the motor control 5 via a bus system 20 in order to control the actuators on the basis of values from sensors.
• the microcomputer 16 executes the method described with reference to FIG. 2, in which it receives the crankshaft position and the angular speed of the crankshaft 2 from the engine control unit 5.
• FIG. 2 shows a flow chart of a particularly preferred method.
• step Sl the internal combustion engine 1 is started after the crankshaft position and the rotational speed of the crankshaft 2 were previously measured and transmitted to the engine control unit 5.
• the rotational speed n of the crankshaft 2 and the position of the crankshaft 2 are continuously measured by a sensor device comprising the gear 3 and the sensor 4. For verification and correction, this information is transmitted to the engine controller 5.
• step S3 the engine controller 5 receives a switch-off signal for a short-term stop of the internal combustion engine 1 due to switch-off conditions, which are transmitted either via the same bus system, a CAN bus 19, or via a separate bus system.
• the switch-off conditions result, for example, from the speed of the vehicle and / or a pedal position and / or gear selection of the vehicle. It is selected by the engine controller 5 or other controller, which is provided for a start-stop operation, an operating strategy, according to which the internal combustion engine 1 and the starting device 7 are controlled in order to as quickly as possible availability of the internal combustion engine 1 at a to be able to provide a changing driver's desired operation.
• the internal combustion engine is switched off after receiving a stop signal due to a start-stop operating strategy.
• the internal combustion engine 1 comes after switching off, for example, a stop of the fuel supply, not immediately to a stop, but runs in a characteristic way.
• a stop of the fuel supply not immediately to a stop, but runs in a characteristic way.
• an angular velocity sets in which characterizes the kinetic energy of the entire system at this point in time.
• the angular velocity in these top dead centers ZOT is measured in a step S4 and the kinetic energy is calculated.
• an indication of the angular velocities to be expected in the next cycles is feasible from the angular velocity as compared to the angular velocities which have been set earlier in one cycle or more cycles.
• the angular velocity Co n is determined in the range of predetermined characteristic positions of the crankshaft 2, which correspond to the ignitable top dead centers (ZOTs), "n” stands for the nth ZOT point, and two determined values during the deceleration become the angular velocity gradient This determines the next and also the following ZOTs, which makes it possible to make a very precise and very precise prediction of the time in the millisecond range and at what speed the next ZOTs are traversed.
• ZOTs ignitable top dead centers
• the brake counteracting the direction of rotation during the engine run-out moment M Br e m s is regarded as a first approximation as constant.
• the braking torque is composed of internal friction torques, heat losses, flow losses and losses due to accompanying auxiliary units.
• 0CBrems ((H n -I 'Co n ) / (t n -rt n )).
• GVi-n GVi - G
• tn + 1 (GVr O n ) / ⁇ B rems + t n
• FIG. 4 shows the typical position of the ZOT values in a time / angular speed diagram for a 6-cylinder internal combustion engine.
• a correction factor due to a plurality of cylinders in the internal combustion engine is additionally calculated in step S5, and the next ZOTs are determined therefrom.
• FIG. 4 shows the angular velocities without a correction factor of cylinder to cylinder deviations for a illustrated 6-cylinder engine with a thin drawn line N.
• the correction factor comprises a cylinder-specific deviation, which is taken into account with the thicker drawn characteristic curve N k , in which the values for Z0T2 and Z0T4 are shown slightly above and the values for ZOT3 are respectively shown below the thinner line N.
• the correction factor consists of the losses during the last decompression phase and the losses of the next compression phase.
• the ZOTs should be traversed in the order shown in FIG. 5, for example, ZOT1, Z0T2, Z0T3, Z0T4, Z0T5 ... ZOTn.
• decompression / compression pairings ie a firing sequence pairing that characterizes the energy loss from ZOT to ZOT, namely in the following pairing equation: (decompression 1 / compression 2), (decompression 2 / compression 3), (decompression 3 / compression 4), (decompression 4 / compression 5), ..., (decompression n / compression n + 1).
• the total torque acting counter to the rotation direction ie. H. the braking torque, considered in first approximation as constant.
• the braking torque is composed of internal friction moments, heat losses, flow losses and losses due to associated auxiliary units.
• step S5 for the internal combustion engine and for the current state of the internal combustion engine the typical individual correction factor for each individual ignition sequence pairing is taken into account.
• the typical correction factor has either been recalculated or is a "learned" correction factor, which has been averaged over the time axis by a linearly falling line N during a runout of the engine at the ZOT times measured times.
• An evaluation of the deviation of the individual speeds in In the case of very short outlets of the internal combustion engine, a plurality of successive outlets of the internal combustion engine are analyzed and evaluated as appropriate.An averaging over a plurality of correction factor determinations increases the accuracy of the correction.
• the angular velocity gradient is evaluated for each individual outlet of the internal combustion engine.
• no values from a stored characteristic map are used to predict the next ZOTs, since the velocity profile is inhomogeneous and has a broad tolerance field, so that no specific statement can be determined.
• the method according to the invention has the advantage that the prediction values for the time and the angular velocity at the next ZOT
• a position-dependent speed measurement of the crankshaft is made in order to make a prognosis for the future.
• step S5 If the controller has determined in step S5 a specific precalculated time in which the starter pinion 9 can be meshed into the ring gear 6 at the same speed, then in step A1 it is queried whether this point in time has been reached. If this time has not yet reached, the controller repeats the
• Steps S4 and S5 detects, calculates and corrects the speed course for the next ZOTs in the millisecond range.
• the controller checks whether a (fine) correction of the Einspurzeitticians is performed due to the latest forecast and the currently adjusting engine speeds and the expected speed of the starter pinion. With this optionally corrected Einspurzeittician the control goes into Step S6 on.
• step S6 the starter pinion 9 is moved at a predetermined time by the starter relay 10 in the axial direction on the axis of the starter 8 and meshed in the toothed rim 6.
• the starter 8 is started depending on the operating strategy either before switching off, simultaneously with the switching off of the internal combustion engine 1 or during the execution of steps S4 and S5 and accelerated to a rotational speed n, which has been determined by the controller in step S5.
• the starter pinion 9 can be Solutionsspurt in a very precise tolerance band with an approximate synchronous speed.
• the starter pinion 9 remains meshed in the ring gear 6 and runs with the internal combustion engine 1, as long as no change in the operating strategy is provided, or no change in the desired operation is transmitted to the engine control 5.
• step S7 the controller checks in accordance with the method described in steps S4 and S5 with which position the crankshaft will come to a standstill.
• crankshaft 2 In a subsequent query A2 is queried whether the crankshaft 2 will come to an ideal position to a halt in order to start the internal combustion engine 1 as quickly as possible, d. H. the crankshaft 2 is at a ZOT, for example, at a favorable angle of about 90 ° before the next ZOT. If this is the case, then the process comes to an end in the control.
• step S8 the starter 8 is supplied with current in the range of milliseconds, so that the crankshaft 2 is brought into a precisely defined position, to start the internal combustion engine 1 as quickly as possible and from an ideal state.
• the starter 8 functions in this step S8 together with the starter control 8 as a servomotor or as an actuator.
• the position of the crankshaft is detected further and possibly the starter 8 briefly energized again, so that the crankshaft 2 comes to a standstill at an intended angle to the next ZOT. Subsequently, the process returns to the end.
• FIG. 3 shows a characteristic curve Ki of the crankshaft 2 with characteristic positions in the outlet of an internal combustion engine 1 after which the internal combustion engine 1 has been switched off, for example.
• characteristic points occur at the so-called ZOTs (ZOT1, Z0T2, Z0T3, Z0T4, Z0T5), in which the speed curve initially drops steeper due to the compression behavior before a working phase of the individual cylinders 11 to 14.
• ZOTs the speed history has local minima or regions with a shallower angular velocity gradient due to the increase in velocity during the decompression phase.
• the linear characteristic curve N shows the angular velocity gradient over time t.
• FIG. 4 shows the position of the ZOT values over a larger time range than FIG. 3 once without the correction of cylinder to cylinder deviations as characteristic curve N and once as characteristic curve N k taking into account the above-described correction factor.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)
• Control Of Vehicle Engines Or Engines For Specific Uses (AREA)

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• 2008
  • 2008-08-06 DE DE102008041037A patent/DE102008041037A1/de not_active Withdrawn
• 2009
  • 2009-06-15 US US12/737,656 patent/US20110184626A1/en not_active Abandoned
  • 2009-06-15 CN CN2009801308229A patent/CN102112721A/zh active Pending
  • 2009-06-15 WO PCT/EP2009/057391 patent/WO2010015449A1/fr active Application Filing
  • 2009-06-15 AT AT09779762T patent/ATE535696T1/de active
  • 2009-06-15 JP JP2011521497A patent/JP2011530036A/ja active Pending
  • 2009-06-15 EP EP09779762A patent/EP2313633B1/fr active Active

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