Classifications

• • 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
  • F02D31/003—Electric control of rotation speed controlling air supply for idle speed control
• • 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
  • F02D41/0005—Controlling intake air during deceleration
• • 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
  • F02D41/08—Introducing corrections for particular operating conditions for idling
• • 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
  • F02D41/08—Introducing corrections for particular operating conditions for idling
  • F02D41/083—Introducing corrections for particular operating conditions for idling taking into account engine load variation, e.g. air-conditionning
• • 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
  • F02D41/14—Introducing closed-loop corrections
  • F02D41/1497—With detection of the mechanical response of the engine
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/10—Parameters related to the engine output, e.g. engine torque or engine speed
  • F02D2200/1006—Engine torque losses, e.g. friction or pumping losses or losses caused by external loads of accessories
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/60—Input parameters for engine control said parameters being related to the driver demands or status
  • F02D2200/602—Pedal position
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2250/00—Engine control related to specific problems or objectives
  • F02D2250/18—Control of the engine output torque
  • F02D2250/22—Control of the engine output torque by keeping a torque reserve, i.e. with temporarily reduced drive train or engine efficiency
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
  • F02P5/00—Advancing or retarding ignition; Control therefor
  • F02P5/04—Advancing or retarding ignition; Control therefor automatically, as a function of the working conditions of the engine or vehicle or of the atmospheric conditions
  • F02P5/145—Advancing or retarding ignition; Control therefor automatically, as a function of the working conditions of the engine or vehicle or of the atmospheric conditions using electrical means
  • F02P5/15—Digital data processing
  • F02P5/1502—Digital data processing using one central computing unit
  • F02P5/1504—Digital data processing using one central computing unit with particular means during a transient phase, e.g. acceleration, deceleration, gear change
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
  • F02P5/00—Advancing or retarding ignition; Control therefor
  • F02P5/04—Advancing or retarding ignition; Control therefor automatically, as a function of the working conditions of the engine or vehicle or of the atmospheric conditions
  • F02P5/145—Advancing or retarding ignition; Control therefor automatically, as a function of the working conditions of the engine or vehicle or of the atmospheric conditions using electrical means
  • F02P5/15—Digital data processing
  • F02P5/1502—Digital data processing using one central computing unit
  • F02P5/1508—Digital data processing using one central computing unit with particular means during idling
• • 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
  • Y02T10/40—Engine management systems

Definitions

• the invention relates to a method for obtaining a supply of air, during a return to idling of an internal combustion engine in a motor vehicle.
• An internal combustion engine more commonly called a gasoline engine, comprises a predetermined number of cylinders, each forming a combustion chamber, capable of allowing the combustion of an air / fuel mixture.
• This combustion is supervised by a computer, also referred to as motor control, configured to adjust, via actuators, various engine operating parameters influencing this combustion, for example: the regulation of the quantity of fuel. air admitted into the cylinders, the mass of fuel injected, or the ignition to trigger combustion.
• Engine idle speed control begins when a driver lifts his foot off the accelerator.
• the computer controls, via actuators, various engine parameters (for example air loop, air injection and / or fuel injection, ignition angle) in order to converge the engine speed to a setpoint value. referring to a target idle speed value that is called a static setpoint.
• the computer commonly uses on-board or associated calculation means, such as a "Proportional Integral Derivative" type idling controller, commonly known as the "PID regulator".
• this type of regulator is activated only for phases of idling and stabilized idling of the engine, and helps the computer to determine the values of the engine parameters to be regulated.
• this PID regulates the speed, N, so that it follows its dynamic setpoint, n.
• the dynamic setpoint, n is initialized at a current engine speed, Ne, determined at initialization at time t0 of the PID regulator and converges towards the static speed setpoint, nr, in the form of a filter of 1 st order.
• the engine In stabilized idle phase, the engine then has a speed typically around 750 rpm.
• the stability of a motor running at idle speed is particularly complex to ensure.
• the return of the engine to an idle speed can vary considerably, depending on the initial depression of the accelerator, the engine temperature, external conditions (temperatures, pressures) or the activation of different vehicle consumers (eg pumps, air conditioner compressor, power steering, alternator).
• the undershoot situation of the engine speed is particularly problematic because it can lead to a vibratory behavior of the engine felt as unpleasant for the driver, or even a stalled situation of the engine, thus creating a security risk.
• the reserve of air torque allows the engine to have more air than necessary to achieve a requested torque.
• This reserve of air torque is obtained by the computer, by controlling earlier the advance (that is to say the angle value) at ignition during a motor cycle.
• the reserve of air torque makes it possible to immediately dispose of a supply of air, compared with the expectation of air intake into the combustion chamber resulting from the opening of the throttle valve of the inlet distributor arranged upstream. of the combustion chamber.
• a static air reserve activated in the engine idling phase, in particular according to the engaged gear ratio, the engine coolant temperature, the air temperature in the intake manifold;
• the air supply remains too late and too weak. Too late, because these two reserves are implemented only when the engine idling is effective.
• the reserve of dynamic torque requires in particular to be close to the optimum ignition angle to be engaged, and refers to a simple air compensation. Such a reserve may be insufficient in relation to the losses in order to maintain the engine idling speed.
• the static reserve is too low, because to limit fuel consumption, it is commonly calibrated to the minimum necessary stabilized idle phase. These reserves may therefore be insufficient to compensate for torque losses during a return to idling out of cut where the throttle is closed, and keep the engine at idle speed. Undershoot situations that could potentially lead to engine stalling, such as those initially presented, may therefore occur. All the existing solutions are therefore limited.
• An object is to meet all the aforementioned drawbacks.
• a second object is to limit the situations of under-revs and over-revving engine for idling phases of an internal combustion engine.
• a third object is to determine an air reserve for idling return phases of an internal combustion engine.
• a fourth object is to improve the driving pleasure of the driver.
• a fifth object is to improve the safety of the vehicle.
• a method for obtaining an air supply for an internal combustion engine fitted to a motor vehicle, during a phase of return to idle speed. of this engine following an accelerator pedal release of the motor vehicle this method being characterized in that it comprises the following steps:
• this predetermined situation being a function of the engine speed
• the predetermined situation corresponds to reaching down by the engine speed, a preconfigured threshold, for which the regulator is not yet active.
• the predetermined situation corresponds to reaching down by the engine speed of a preconfigured threshold, corresponding to a maximum activation range terminal. the idle speed regulator.
• the predetermined situation corresponds to the activation of the idle speed controller.
• the air reserve torque is determined as follows:
• the air reserve torque is determined as follows:
• the calculations include:
• the method comprises a step of determining a factor to reduce the air torque reserve value to a zero value, during driving idling situations of the motor vehicle.
• this method further comprises a step of filtering the air reserve torque via a low-pass filter.
• the idle speed regulator is a Proportional Integral Derivative derived type regulator.
• a computer fitted to a motor vehicle configured to apply a method of obtaining an air reserve for an internal combustion engine, during a return to idle of this This method is summarized above.
• Figure 1 illustrates an idle speed regulation according to the prior art.
• FIG. 2 illustrates a regulation of idle speed according to the prior art, with the presence of under revolutions and over-revving idle.
• FIG. 3 illustrates by a logic diagram the construction of the reserve torque according to the invention.
• FIG. 4 illustrates a motor vehicle comprising a motor and a computer programmed to regulate operating parameters of this motor according to various embodiments;
• FIG. 5 illustrates the evolution of the engine speed, its setpoint value, as well as the activation ranges of an air reserve according to various embodiments.
• Figure 5 illustrates a vehicle 100 automobile equipped with a spark ignition internal combustion engine 1 (name referring to combustion), more commonly called gasoline engine 1.
• a spark ignition internal combustion engine 1 name referring to combustion
• gasoline engine 1 more commonly called gasoline engine 1.
• the internal combustion engine 1 is controlled by a computer 2 (also called engine control), the computer 2 being programmed to best meet the will of the driver, retransmitted including via an accelerator pedal.
• the computer 2 receives various information, including those from a sensor positioned on the accelerator pedal, this information allowing it to control in particular the operating speed of the engine 1.
• the internal combustion engine 1 comprises a predetermined number of cylinders each forming a combustion chamber, to allow the combustion of an air / fuel mixture controlled according to a predefined cycle, for example following a four-stroke cycle.
• the combustion in each cylinder is triggered by an ignition device, such as a candle disposed in an upper portion of the cylinder, this device for producing the spark necessary for the combustion of the air / fuel mixture.
• the work produced by the internal combustion engine 1 comes from the combustion, initiated by the ignition device of the air / fuel mixture compressed within each cylinder by an alternately moving piston, between an extreme high position. and an extreme low position, relative to the cylinder, respectively called High Dead Point (TDC) position and Low Dead Position (TDC) position.
• the reciprocating movement of the piston enables the rotation of a crankshaft by means of a connecting rod connecting the piston to the crankshaft, the movement of the crankshaft being then transmitted to the wheels of the vehicle 100 via various mechanisms.
• ignition of the air / fuel mixture via the ignition device, occurs upstream of the piston position PMH at the end of the compression phase.
• ignition advance corresponding to an angular difference (expressed for example in degrees), having for reference the crankshaft, between the moment of ignition and the ignition. moment of the passage of the piston to the top dead center (TDC) position, the top dead center position (TDC) of the piston corresponding to the reference position.
• this ignition advance value is controlled by the computer 2.
• the fuel is injected directly into the combustion chamber (direct injection), or otherwise upstream of the combustion chamber (indirect injection), the injection being performed by injectors and driven by the calculator 2.
• Each cylinder is connected to an intake distributor, allowing the transport of air or air / fuel mixture to the different combustion chambers, and output to an exhaust manifold for exhaust gas of combustion.
• the air regulation through the inlet distributor is provided via an air regulating valve, for example a motorized throttle, whose opening section is controlled by the computer 2.
• the computer 2 is connected by transmission lines to different sensors that provide real-time data on the automobile vehicle 100, and in particular on the engine 1.
• sensors that provide real-time data on the automobile vehicle 100, and in particular on the engine 1.
• the speed N of the engine corresponds to the number of rotation performed by the engine 1, and more precisely by the crankshaft, per unit of time. It is generally expressed in rpm and is measured by a rotational speed sensor;
• the engine temperature it corresponds to the temperature of the engine coolant (for example a water / antifreeze mixture), the temperature of the lubricating oil at the cylinder, or the temperature of the material of a sensitive constituent of the engine 1 (for example a zone of the cylinder head). It is generally measured by a temperature probe;
• the position of the accelerator it corresponds to the level of depression of the accelerator pedal, this depression being generally measured by a position sensor on the accelerator pedal;
• the pressure P in the intake manifold it corresponds to the air pressure in this element, the latter being measured by a sensor placed in the intake manifold.
• the computer 2 develops and controls control strategies of the engine 1, in particular via
• control signals controlling the injection for example: the mass of fuel injected, the duration of the injection; generating control signals controlling each ignition device, for independently controlling the ignition of each cylinder, and therefore the ignition timing;
• control signals controlling the motorized throttle upstream of the intake distributor thus allowing the regulation of the air pressure in this member.
• the computer 2 comprises various calculation means, including servocontrol means, for controlling the speed N of the engine 1 to a dynamic reference speed n value.
• servocontrol means for controlling the speed N of the engine 1 to a dynamic reference speed n value.
• the computer 2 is associated with an idle speed controller, in charge of calculating the evolution of the values of different operating parameters of the engine 1, the application of these values making it possible to converge the speed N of the engine 1 to the dynamic set point n value.
• the idle speed controller is disabled during the acceleration phases, and reactivated during the idling phases.
• the computer 2 then applies the determined values to the engine 1 via actuators.
• the computer 2 controls via actuators, the values of the opening section of the air regulating valve, the injection (duration, fuel mass) or in advance. ignition, so as to ensure the follow-up by the N speed of the engine 1 of the dynamic reference value n.
• the idle speed regulator is of the "Proportional Integral Derivative" type, and hereinafter referred to as the "PID regulator".
• the setpoint n speed value is controlled by the computer 2 to a nominal value nr of static engine idling speed (function of the gear ratio engaged), value to which it is desired to converge the speed N of the motor, which corresponds to a static setpoint.
• the dynamic reference speed n value is
• the calculation of the static or dynamic value of the setpoint is, by way of example, carried out according to a method of the state of the art.
• the value of the dynamic reference speed n is controlled by the computer 2 at the current value of the engine speed N, and then driven so as to decrease (eg exponential via a time constant as a function of the motor gradient) to the value of steady state nr.
• the speed N of the engine 1 is regulated according to various parameters whose values are determined by the idle speed controller and controlled by the computer 2. More precisely the operating parameters of the engine 1 (butterfly valve, injection, ignition advance) are controlled by the computer 2 (via actuator) following activation of the idle speed controller.
• the speed curves N of the engine 1 and the dynamic reference speed n value are confused from the moment t1: the N speed of the engine 1 converges here instantly with the value of the speed n setpoint, which is brought gradually to the final value of regime nr static setpoint.
• the engine speed N may, after the instant t1, differ from the setpoint n speed value, and then converge later to the static target speed nr value.
• the speed curves N of the engine 1 and the value of the dynamic setpoint n are therefore not always necessarily confused after the instant t3.
• the computer 2 is configured to detect, according to the speed N of the engine 1, the occurrence of a predetermined situation depending on the engine speed.
• the predetermined situation may be:
• the time gradient dN / dt (variation of the speed N as a function of a time t) of the speed N of the engine 1, that is to say the deceleration rate of the speed N of the engine 1; the comparison of this time gradient dN / dt with a predetermined theoretical gradient derived for example from a cartography;
• This pair of losses is, by way of example, determined by calculation or via a cartography, as a function of the following parameters: speed of the vehicle 100, speed N of the engine 1, friction losses in the engine 1 (for example depending on its temperature, of the viscosity of its lubricating oil), losses induced by the various electrical consumers of the vehicle 100 or mechanical (for example oil pump, compressor of the air conditioning);
• open-loop torque PID controller torque + open loop torque
• the concept of open loop means, here, that the value of idle torque is obtained via the application of a preconfigured mathematical formula on these inputs, the output obtained (idle torque) not looping back with these inputs, as opposed to a closed loop situation which can for example occur in stabilized idle phase of the engine 1; o an activation decision t1 of the idle speed controller (eg of the PID type) as a function of the time gradient dN / dt and the engine N speed 1: the idle speed controller is activated if the time gradient dN / dt is less than the gradient theoretical time. this instant of activation t1 of the idle speed regulator being later than the moment of exceeding the threshold Ns preconfigured;
• the idle speed regulator determines the values of the various operating parameters of the engine 1 (ignition advance, injection, opening of the motorized throttle) to be regulated, so as to converge the speed N towards the value steady state nr.
• the computer 2 activates a reserve of air, in order to anticipate any risk of lack of air, and therefore any risk of engine N falling down which can lead to a situation of under -regime, even calibration.
• this air reserve for the three situations described above is respectively represented by the double arrows 201, 202, 203. It is observed here that this reserve of air remains activated until obtaining a stabilized idling speed of the engine 1 to the value of steady state nr.
• the air reserve is obtained by calculating an air reserve torque. If the air reserve is not activated, that is to say when the predetermined situation is not detected, the reserve air torque associated with this air reserve is maintained at a value of zero (at 0). Nm) by the calculator 2.
• the computer 2 may determine the air reserve torque in it. assigning successively for value, the difference at each moment between the loss pair and the open-loop torque;
• the computer 2 can also determine the reserve air torque by attributing to it, for initial value, the value of the instantaneous loss couple as that the regulator is activated, then gradually decreasing the value of this air reserve torque as a function of the difference at each instant between the loss torque and the open loop torque when the idle speed controller is activated.
• the air reserve torque is translated into air mass by the computer 2, via an adjustment of the operating parameters of the engine 1.
• the computer 2 regulates the opening of the motorized throttle and / or the value of the ignition advance, according to values making it possible to obtain the air reserve torque and therefore the corresponding air reserve.
• the reserve air torque is therefore added to the idle torque determined by the computer 2.
• the air reserve torque 33 is, by way of example, determined from a two-dimensional cartography 30, by correspondence between a loss torque value, and a difference between the value loss torque 31 and a value 32 of idle torque in open loop.
• mapping makes it possible to target different situations:
• this mapping matches a zero value to the air reserve torque. Indeed, only pairs of losses judged to be sufficiently high require a non-zero value of air reserve torque, in order to anticipate any risk of a fall in speed N (linked to the torque setpoint that can not be achieved due to lack of air );
• the engine torque compensates the internal and external losses to the engine 1.
• the engine torque 1 relating to this regime is then equal to the open-loop torque plus the torque of the PID regulator and this value should be close to the loss torque, as well as the open-loop torque. It is therefore no longer necessary to have the air reserve torque. This translates in the mapping, by a zero value of the air reserve torque, when the difference between the loss torque and the open-loop idling torque is zero.
• the computer 2 determines a factor making it possible to reduce the air torque reserve value to a zero value during the situations of idling caused, thus making it possible to exclude these situations.
• This factor is by way of example determined from a map, making it possible to achieve the correspondence between different predetermined factor values and different gearbox ratios.
• the air torque reserve is in particular a function of the loss torque. Typically, this pair of losses is very fluctuating and therefore has a "noise" which therefore affects the determination of the air torque reserve.
• the strategy for calculating the reserve then applies, in one embodiment, a low-pass filter once this value has been determined.
• the previously described embodiments make it possible to propose an air reserve during a return to idling, whereas the state of the art is limited to considering a reserve of air for idling phases. stabilized motor 1. More precisely, the state of the art proposes mainly to compensate for a lack of air compensation, when it is proven, via the use of static and dynamic reserves. By contrast, all of the proposed embodiments can anticipate a lack of air during a return to idle, while the torque is taken from the engine 1, via the sending by the computer 2 of instructions to different actuators (eg actuators control the butterfly valve, injectors).
• actuators eg actuators control the butterfly valve, injectors.
• overshoot situations resulting from temporary compensation by the idle controller of an under-regime situation are also limited.
• the described embodiments thus contribute not only to improving the fuel consumption in the automobile vehicle 100, but also to improving the driving comfort of the driver by limiting the vibration behavior observed during possible engine sub-revs and over-revs 1.

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• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
• Combined Controls Of Internal Combustion Engines (AREA)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

Country Status (3)

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• 2015
  • 2015-06-10 FR FR1555273A patent/FR3037359B1/fr active Active
• 2016
  • 2016-05-30 EP EP16731237.0A patent/EP3308005A1/de not_active Withdrawn
  • 2016-05-30 WO PCT/FR2016/051283 patent/WO2016198763A1/fr active Application Filing

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