CN103047039A - Engine control device - Google Patents

Abstract

Provided is an engine control device, possessing a target ignition time calculating unit (6A) for calculating a target ignition timing for introducing air amount into a cylinder (19) of an engine (10) by a computer; a thermal efficiency calculating unit (7) for calculating engine thermal efficiency according to the target ignition timing; and a target air amount calculating unit (4), according to the thermal efficiency, calculating a target value of air amount to be introduced into the cylinder (19), i.e., a target air amount. In addition, the target ignition time calculating unit (6A) calculates a target ignition timing in a present calculating period according to a target air amount in a past calculating period. According to the invention, control responsiveness and stability of absorption air amount control can be improved; when an operating point of an engine changes in torque reference control, a convergence performance of the operating point of an engine as a target is raised.

Description

The control gear of motor

Technical field

The present invention relates to a kind ofly require moment of torsion and the control gear of the motor of control engine output power according to motor is desired, relate in particular to and a kind ofly use engine thermal efficiency and the control gear of computing target empty tolerance.

Background technique

As one of controlling method of carrying the motor on vehicle, known have the moment of torsion benchmark (torque demand) of air amount amount, fuel injection amount and time of ignition etc. being controlled take the desired torque of motor as benchmark to control.In moment of torsion benchmark control, for example come the desired value of the moment of torsion that the computing motor should export according to accelerator open degree and engine rotary speed, and the operating condition of control engine is to obtain this target torque.In addition, be equipped with automatic speed variator, self-reacting device, be called in the vehicle of external control system of vehicle stabilization device, by each external control system the output of motor is required to be converted into torque value and engine controlling unit (Engine ECU) in by unified, the moment of torsion of control engine moves in the lump.

In the past, in the control of this moment of torsion benchmark, known have a kind of to the two kind controls not identical with respect to the responsiveness of control operation, namely to replying slowly moment of torsion control and replying soon moment of torsion and control the technology of all being implemented.The former moment of torsion control of replying slowly is to operate control torque according to for example air amount amount that is operating as representative with electronic control throttle.In addition, the latter's the moment of torsion control of replying soon is to operate control torque according to for example time of ignition operation, fuel injection amount.These are controlled, and not only responsiveness is not identical, and the adjusting range of moment of torsion is not identical yet, therefore, suitably implements according to the travelling state of vehicle and the operating condition of motor, or adjusts in phase the operation amount of each control.For example, patent documentation 1 records a kind of basis is controlled throttle valve and spark plug by the operating condition of air flow sensor or the detected motor of intake manifold pressure sensor moment of torsion benchmark control gear.In this technology, air inflow control device control air amount amount, time of ignition control device control time of ignition.

Yet in the control of the air amount amount of moment of torsion benchmark, the control throttle valve opening is so that the air quantity that the amount of the air by throttle valve occurs for the combustion reaction that makes abundant necessity for producing target torque.Namely, come computing should import the desired value of the air amount amount in the cylinder according to target torque, consider the kinetic characteristic union target throttle valve as fluid of the air amount corresponding with pressure condition, the temperature conditions of gas handling system system, corresponding throttle valve output control signal is so that actual throttle opening is consistent with this target throttle valve.By making in this way, can suitably regulate the air amount amount to target torque.

On the other hand, the actual Engine torque that generates is to change according to being inhaled into air quantity in the cylinder and the fuel quantity of mixed gas along with the combustion reaction in the cylinder.This is because the cause of the thermal efficiency because changing on opportunity of the oxygen concentration in the air amount and burning etc.Here, convert the energy proportion after the mechanicalness work of motor in the heat that the thermal efficiency refers to produce in the cylinder to.Therefore, in the control of in recent years moment of torsion benchmark, adopting such method: in the calculating process of throttle opening, with the Efficiency Calculation of motor, use in the lump this thermal efficiency and target torque and computing air amount amount correctly.

As the computational methods of the typical thermal efficiency, the time of ignition of known with good grounds each cylinder and the method calculated.For example, utilize the relation of time of ignition and moment of torsion to calculate the Engine torque in this moment, by to the information of its additional rotational speed and calculation engine output power (being power).So, infer accurately engine output according to the operating condition of the motor of reality, can hold the energy corresponding with the thermal efficiency, but the correct thermal efficiency value of computing.

Patent documentation 1: TOHKEMY 2009-281239 communique

Invent problem to be solved

But, in the computational methods based on the thermal efficiency of the time of ignition of each cylinder, be difficult to hold without the ground that lags behind the operating condition of motor.For example, in the time of ignition control of general moment of torsion benchmark, set time of ignition according to the sensor checkout value corresponding with the real-world operation state of motor.Object lesson as the sensor checkout value is to use the amount of actual air for combustion and the actual charging efficiency that are detected by the flowmeter that is located at gas handling system.Even in the technology that above-mentioned patent documentation 1 is put down in writing, also the checkout value according to air flow sensor and mainfold presure (air-distributor pressure) sensor arranges time of ignition.

On the other hand, the value of amount of actual air for combustion and actual charging efficiency, be for the realize target charging efficiency as the resulting numerical value of result after throttle valve etc. is operated, its for this time target charging efficiency inscribed reply with lagging behind.That is, detect amount of actual air for combustion and actual charging efficiency according to the sensor checkout value, its be from computing the moment of target charging efficiency through carrying out after the lag time of regulation.And, comprise the driving lag time of the motor that is built in throttle valve the lag time of this regulation until the operation time of the control signal that is delivered to throttle valve being carried out spend till the computing.

Therefore, if use the time of ignition of setting according to amount of actual air for combustion and actual charging efficiency to come calculating thermal efficiency, then the numerical value of this thermal efficiency also is relative target charging efficiency and the numerical value that postpones.Thus, between the moment of torsion action of foundation time of ignition control and the moment of torsion action according to the control of air amount amount, produce easily deviation, might descend as the convergence for engine running point of target.In addition, owing to apply the operation that the control of air amount amount is lagged behind slightly with respect to time of ignition control, therefore also has such problem: both be difficult to make the action of throttle valve to achieve the goal, and be difficult to again make the responsiveness of air amount amount control and stability to improve.

Summary of the invention

The present invention invents in view of problem as described above, one of its purpose is to provide a kind of control gear of motor, when the operation point of motor in the control of moment of torsion benchmark changes, the convergence for engine running point as target is improved, and the control responsiveness of air amount amount control and control stability are improved.In addition, purpose of the present invention is not limited to above-mentioned purpose, can also obtain the action effect that brought by each structure shown in the mode be used to carrying out an invention described later, namely obtain the action effect that conventional art can not obtain, this is also located as another object of the present invention.

Be used for solving the means of problem

(1) control gear of motor disclosed herein has: the target ignition moment arithmetic element that the target ignition that the air quantity of calculating in the cylinder that should import motor is used carries out computing constantly; The thermal efficiency arithmetic element of constantly thermal efficiency of described motor being carried out computing according to described target ignition; And according to the target empty tolerance arithmetic element of the described thermal efficiency to carrying out computing as the target empty tolerance that should import the desired value of the air quantity in the described cylinder, described target ignition is the described target empty tolerance that calculates according in the past execution cycle in described target empty tolerance arithmetic element of arithmetic element and the time interim described target ignition of current execution cycle is carried out computing constantly constantly.

Said " should import the air quantity in the engine cylinder " comprises volume, quality or the parameter corresponding with them that imports the air of (after importing) in the engine cylinder herein, such as comprising charging efficiency and volumetric efficiency etc.In addition, " target ignition constantly " among the present invention is the time of ignition that the implementation time of ignition used with the spark plug actual ignition separates, and needs not to be the numerical value identical with carrying out time of ignition.Namely, " target ignition constantly " is not the common meaning that is called the desired value of carrying out time of ignition, but for calculating the required information of target empty tolerance, refer to the meaning of the time of ignition of target operation point, should " target ignition is constantly " be to come computing according to the target empty tolerance in past.In addition, so-called " the target empty tolerance in past " comprises such as in the resulting target empty tolerance of the execution cycle of last time, in the resulting target empty tolerance of the first two execution cycle etc.In addition, so-called " according to the target empty tolerance in past " comprises: the numerical value that for example intactly uses the last time of target empty tolerance; The use of using the numerical value of last time and the mean value of the numerical value of upper last time etc. is implemented numerical value after the various computings to the target empty tolerance in past.

(2) in addition, preferably, the target air-fuel ratio arithmetic element that has according to the described target empty tolerance that calculates at the execution cycle in described past and the time interim target air-fuel ratio of current execution cycle is carried out computing, described thermal efficiency arithmetic element is revised the thermal efficiency of described motor according to described target air-fuel ratio.By the described target air-fuel ratio of described target air-fuel ratio arithmetic element computing, refer to that for calculating the essential information of target empty tolerance be the air fuel ratio of target operation point, it is to carry out computing according to the target empty tolerance in past.

(3) in addition, preferably, have the target exhaust reflux ratio arithmetic element of the time interim target exhaust reflux ratio of current execution cycle being carried out computing according to the described target empty tolerance that calculates at the execution cycle in described past, described thermal efficiency arithmetic element is revised the thermal efficiency of described motor according to described target exhaust reflux ratio.By the described target exhaust reflux ratio of described target exhaust reflux ratio arithmetic element computing, refer to that for calculating the essential information of target empty tolerance be the exhaust gas recirculation rate of target operation point, it is to carry out computing according to the target empty tolerance in past.

(4) in addition, preferably, the described target empty tolerance that the execution cycle of described target ignition moment arithmetic element basis before just calculates is carried out computing constantly to the described target ignition of current execution cycle.

(5) in addition, preferably, has the implementation time of ignition arithmetic element that the implementation time of ignition corresponding to the moment of being lighted a fire by spark plug according to the amount of actual air for combustion pair and the reality that are imported in the cylinder of described motor carries out computing.For example, when the transition operation that described target gas amount changes, preferably, described target ignition constantly arithmetic element is independent of the described target ignition that the ground-to-air tolerance computing of described implementation time of ignition uses and constantly carries out computing.

The effect of invention:

In the control gear of disclosed motor, the execution cycle that the target empty tolerance that calculates according in the past execution cycle and computing are current the time target ignition inscribed constantly, by according to this target ignition constantly and the thermal efficiency computing of computing should import the target empty tolerance in the engine cylinder.Utilize this computing, the length of the retard time of the relative target empty tolerance of amount of actual air for combustion no matter, all can suitably control the air amount amount, when the operation point of motor changes, can make rapidly and accurately it converge to engine running point as target.In addition, the thermal efficiency can be held accurately, the controlled raising of air amount amount control can be made.

Description of drawings

Fig. 1 be illustration one mode of execution motor control gear frame structure and be suitable for the figure of structure of the motor of this control gear.

Fig. 2 is the ideograph that the computing flow process of parameter is used in the control of this control gear of expression.

Fig. 3 is the frame assumption diagram of the target torque operational part of this control gear of illustration.

Fig. 4 is the frame assumption diagram of the time of ignition control device of this control gear of illustration.

Fig. 5 is the frame assumption diagram of the target charging efficiency operational part of this control gear of illustration.

Fig. 6 is the frame assumption diagram of the air inflow control device of this control gear of illustration.

Fig. 7 is the frame assumption diagram of the target ignition moment operational part of this control gear of illustration.

Fig. 8 is the frame assumption diagram of the target air-fuel ratio operational part of this control gear of illustration.

Fig. 9 is the frame assumption diagram that the target EGR of this control gear of illustration leads operational part.

Figure 10 is the frame assumption diagram of the coefficient of thermal efficiency operational part of this control gear of illustration.

Symbol description:

1 engine controlling unit

2 target torque operational parts

3 time of ignition control devices (carrying out the time of ignition arithmetic element)

4 target charging efficiency operational parts (target charging efficiency arithmetic element)

5 air inflow control devices

6 desired value operational parts

The 6A target ignition is operational part (target ignition is arithmetic element constantly) constantly

6B target air-fuel ratio operational part (target air-fuel ratio arithmetic element)

6C target EGR leads operational part (target exhaust reflux ratio arithmetic element)

7 coefficient of thermal efficiency operational parts (thermal efficiency arithmetic element)

Ec _TGTThe target charging efficiency

Ec _{TGT_PRE}The numerical value of last time

K _PiCoefficient of thermal efficiency

Embodiment

The control gear of motor is described with reference to accompanying drawing.In addition, below the mode of execution of expression only is illustration, the intention that the various distortion that the following mode of execution of nothing eliminating is not expressed and technology are used.Each structure of present embodiment can be done various distortion and implement in the scope that does not break away from these purports, and can accept or reject, select as required, but or appropriate combination.

[1. apparatus structure]

[1-1. power-transmission system]

The control gear of the motor of present embodiment is used for vehicle-mounted petrol engine 10 shown in Figure 1.In a plurality of cylinders that are located on the multicylinder engine 10 one is shown herein.Dress up in the piston 16 and can reciprocatingly slide freely along the inner peripheral surface of the cylinder 19 that forms hollow cylindrical.Play the function of the firing chamber 26 of motor by the upper surface of piston 16 and the inner peripheral surface of cylinder 19 and the space that end face impales.The bottom of piston 16 is connected with the cranking arm of central shaft that has from bent axle 17 axle center off-centre by connecting rod.Thus, the reciprocating action of piston 16 is passed to cranks arm, and converts rotatablely moving of bent axle 17 to.

At the end face of cylinder 19, be formed through and be useful on the relief opening 12 that air amount is supplied to the suction port 11 in the firing chamber 26 and is used for the exhaust after 26 internal combustion of firing chamber is discharged.In addition, be provided with intake valve 14 and exhaust valve 15 in the end of the firing chamber of suction port 11, relief opening 12 26 sides.The action separately of these intake valves 14, exhaust valve 15 is respectively by the not shown valve mechanism control of being located at motor 10 tops.In addition, at the top of cylinder 19, spark plug 13 be set as its top to the firing chamber 26 side-prominent states.The time of ignition that spark plug 13 carries out is by engine controlling unit 1 control described later.Be provided with water jacket 27 around cylinder 19, engine cooling water is at the internal circulation of this water jacket 27.Engine cooling water is the refrigerant that motor 10 is cooled off usefulness, and it connects between with water jacket 27 and radiator in the cooling water circulation path of ring-type and circulates.

[1-2. air inlet system and exhaust system]

In suction port 11, be provided with the sparger 18 of burner oil.Controlled by engine controlling unit 1 described later from the fuel quantity that sparger 18 sprays.In addition, be provided with intake manifold 20 at the upstream side from the inlet stream of sparger 18.Be provided for the temporary transient knock out drum 21 that stores the air that flows to suction port 11 sides on this intake manifold 20.The intake manifold 20 of comparing downstream side on the lower with knock out drum 21 forms suction port 11 differences to each cylinder 19, and knock out drum 21 is positioned at its ramification point.Knock out drum 21 plays charge pulsation and the air inlet that can produce each cylinder and interferes the function that is relaxed.

Upstream side in intake manifold 20 is connected with tb 22.Keep electronic control type throttle valve 23 in the inside of tb 22, the air quantity that flows to intake manifold 20 sides is conditioned according to the aperture (throttle opening) of throttle valve 23.This throttle opening is by engine controlling unit 1 control.More upstream side at tb 22 is connected with inlet air pathway 24.In addition, the more upstream side at inlet air pathway 24 has clamped air filter 25.Thus, supplied to each cylinder 19 of motor 10 by inlet air pathway 24 and intake manifold 20 by the new air after air filter 25 filtrations.

In the downstream side of relief opening 12 gas exhaust manifold 30 is set.Gas exhaust manifold 30 forms and makes the shape of being collaborated from the exhaust of each cylinder 19, and it is connected with exhaust catalyst device with the not shown exhaust passageway in its downstream side and is connected.Be connected by return flow path 40 between inlet air pathway 24 and the gas exhaust manifold 30, the way is provided with cooler 29 and reflux valve 28 therein.Return flow path 40 is so-called EGR (exhaust gas recirculatioon, Exhaust Gas Recirculation) paths, and it is the path that a part of exhaust is circulated to inlet air pathway 24 sides again.Current return circuit 40 one ends among Fig. 1 are connected on the position (gas exhaust manifold 30) that approaches with relief opening 12, and the other end is connected on the downstream side (knock out drum 21 sides) of comparing with throttle valve 23 on the lower.Below, also will be called EGR gas by the exhaust that current return circuit 40 imports to the air inlet side again.

Cooler 29 is for the heat exchanger of cooling down high-temperature exhaust (radiator).In addition, reflux valve 28 is to import to the control valve of regulating on opportunity of inlet air pathway 24 sides to the flow of EGR gas with EGR gas.The aperture of reflux valve 28 and opportunity that aperture is changed are by engine controlling unit 1 control.

[1-3. detection system]

Be provided with the intake manifold pressure sensor 31 of detected pressures in the downstream side of throttle valve 23.Intake manifold pressure sensor 31 detects the suction pressure (pressure in the knock out drum 21) of comparing downstream side on the lower with throttle valve 23 and as downstream pressure P _IMIn addition, be provided with atmosphere pressure sensor 32 in the inside of engine controlling unit 1 or the arbitrary position of vehicle.

Atmosphere pressure sensor 32 detects pressure (barometric pressure) P of atmosphere _BPBarometric pressure P _BPThe pressure (comparing the pressure of top upstream side with air filter 25) that can be used as inlet air pathway 24 entrances is processed.Therefore, also can be according to barometric pressure P _BPInfer the upstream pressure P of throttle valve 23 _THU, can be not pressure transducer be set, upstream pressure P at the upstream side of throttle valve 23 yet _THUBe the pressure in the inlet air pathway 24 of comparing top upstream side with throttle valve 23.

For example, with motor 10 with actual rotational speed Ne and charge flow rate Q _INCorresponding from the inlet air pathway entrance to throttle valve 23 gas handling system pressure loss value pre-stored in engine controlling unit 1, by from barometric pressure P _BPDeduct gas handling system pressure loss value and can obtain the upstream pressure P of throttle valve 23 _THU

In addition, in inlet air pathway 24, be provided with detection charge flow rate Q _INAir flow sensor 33.Charge flow rate Q _INThe parameter corresponding with the air mass flow of passing through throttle valve 23.For 19 the inlet stream from throttle valve 23 to cylinder, owing to produce the hysteresis (hysteresis is replied in so-called air inlet) that is caused by circulating resistance or air inlet inertia, therefore, at a time between point import to the flow of air of cylinder 19 with not necessarily consistent in this air mass flow of constantly passing through throttle valve 23.

In addition, except above-mentioned air inlet is replied the hysteresis, the action of throttle valve 23 produces to drive and lags behind.So-called this driving lags behind, be from throttle valve 23 receive from the time of the control signal of engine controlling unit 1 light until in fact the throttle opening of throttle valve 23 change and finish into such as institute's time spent till the indicated state of control signal.In addition, also can be considered to the driving lag time that also is contained in throttle valve 23 operation time of the control signal in the engine controlling unit 1.In this engine controlling unit 1, by implementing this air amount amount control of considering the impact of throttle valve 23 various hysteresis, improve the convergence of engine running point.

Arbitrary position on water jacket 27 or cooling water circulation path is provided with temperature (the coolant water temperature W to engine cooling water _T) cooling water temperature sensor 34 that detects.In addition, the arbitrary position on the circulating path of the food tray of motor 10 or engine motor oil is provided with temperature (the oil temperature O to engine motor oil _T) the engine oil temperature sensor 36 that detects.Described barometric pressure P _BPAnd these coolant water temperatures W _TWith oil temperature O _TBe used for holding the operating condition (environmental conditions) of zero load loss and motor 10.So-called zero load loss is mechanicalness loss of motor 10 self inherence etc.

The engine rotary speed sensor 35 that detects its angle of rotation is set at bent axle 17.The variable quantity of the time per unit of angle of rotation (angular velocity) is proportional with the actual rotational speed Ne (actual speed of time per unit) of motor 10.Therefore, engine rotary speed sensor 35 has the function of the actual rotational speed Ne that obtains motor 10.In addition, also can make according to by engine rotary speed sensor 35 detected angle of rotation in the structure of the actual rotational speed Ne of internal arithmetic of engine controlling unit 1.

In the arbitrary position of vehicle, the operation amount of entering into (the accelerator open degree A to gas pedal is set _PS) accelerator open degree sensor 37 that detects and to external air temperature A _TThe external air temperature sensor 38 that detects.Accelerator open degree A _PSBeing the parameter corresponding with driver's acceleration request, namely is to require corresponding parameter with output to motor 10.In addition, external air temperature A _TThe parameter relevant with the kinetic characteristic of the air amount that passes through throttle valve 23.Obtained the barometric pressure P of (exclusive disjunction) by above-mentioned various sensors 31～38 _BP, upstream pressure P _THU, downstream pressure P _IM, charge flow rate Q _IN, actual rotational speed Ne, oil temperature O _T, coolant water temperature W _T, external air temperature A _T, accelerator open degree A _PSEach information be passed to engine controlling unit 1.

[1-4. control system]

Be provided with engine controlling unit 1 (engine electronic control unit, Engine Electronic Control Unit, control gear) at the above-mentioned vehicle that is equipped with motor 10.This engine controlling unit 1 constitutes such as microprocessor or with the electronic device of the integrated LSI device that forms such as ROM, RAM or assembling, and is connected with the order wire of In-vehicle networking on being located at vehicle.In addition, on In-vehicle networking, the various known electric control device that for example is called braking force control system, control unit for transmission, vehicle stabilization control device, air conditioning control device, electronic product control gear is connected to mutually and can communicates by letter.Electric control device beyond the engine controlling unit 1 is called external control system, will be called the external loading device by the device of external control system control.

Engine controlling unit 1 is the electric control device that the widely system of the ignition system of motor 10, fuel system, air inlet system and exhaust system and valve system and so on is given comprehensive control, is the device of being controlled to the time of ignition of the air quantity of each cylinder 19 of motor 10 and EGR amount, fuel injection amount, each cylinder 19 supplying with.Here, the moment of torsion benchmark of implementing take motor 10 desired torque as benchmark is controlled.As the concrete control object of engine controlling unit 1, can enumerate the aperture etc. of time of ignition, throttle valve 23 and the reflux valve 28 of the fuel quantity that sprays from sparger 18 and time for spraying, spark plug 13.

In the control of this moment of torsion benchmark, as motor 10 desired moments of torsion, supposing has three kinds to require moment of torsion.The first requirement moment of torsion is corresponding with driver's acceleration request, and second requires moment of torsion with corresponding from the requirement of external loading device.These require moment of torsion to say all is the moment of torsion that calculates according to the load that acts on motor 10.On the other hand, the 3rd to require moment of torsion be that actual rotational speed Ne with motor 10 is maintained in the moment of torsion that requires that the rotation feedback control of target rotational speed uses, even be the moment of torsion that requires that also be not considered under the no load condition of service load on the motor 10.These require moment of torsion to automatically switch according to the operating condition of motor 10.With second require moment of torsion be divided into air inlet control with and IGNITION CONTROL situation about using under, motor 10 desired moments of torsion also can be used as four kinds and process.

Below, describe air amount amount control relevant with the air inflow of the cylinder 19 that is directed to motor 10 in the moment of torsion benchmark control of being implemented by engine controlling unit 1 and the time of ignition control relevant with the time of ignition of spark plug 13 in detail.The control of air amount amount mainly utilizes the regulation of throttle valve 23 to realize.In addition, refer to illustrated mean effective pressure (will calculate according to the indicator diagram of motor 10 with the force value of merit after divided by stroke capacity) for embodying the used mark Pi of moment of torsion in the present embodiment, here, embody the size of moment of torsion with illustrated mean effective pressure Pi.In the present embodiment, be not only the moment of the power that produces in the motor 10, and for simplicity, also the moment of torsion a great deal of (pressure corresponding with moment of torsion) that is embodied by the mean effective pressure on the piston 16 that acts on motor 10 (for example illustrated mean effective pressure Pi or clean mean effective pressure Pe) is also referred to as " moment of torsion ".

[2. control summary]

Be conceived to control with the computing flow process of parameter (the following parameter that only is called), each summary that the air amount amount is controlled and time of ignition is controlled of being implemented by engine controlling unit 1 is described.

As shown in Figure 2, in the time of ignition control of this engine controlling unit 1, with IGNITION CONTROL target torque Pi _TGTMake the desired value of the Engine torque that can be guaranteed by the adjustment of time of ignition.Because the desired value of this time of ignition is in fact to be carried out the time of ignition of igniting by spark plug 13, therefore, is called and carries out time of ignition SA _ACTOn the other hand, as the parameter of the real-world operation state of relevant motor 10, use actual rotational speed Ne and the charge flow rate Q of motor 10 _INBecause charge flow rate Q _INRelevant with the actual air amount amount that is directed in the cylinder 19 that becomes control object, therefore, the amount of actual air for combustion in the cylinder is and charge flow rate Q _INCorresponding numerical value.In addition, in the present embodiment, using the suitable parameter of amount of actual air for combustion is actual charging efficiency Ec.

When the air amount amount is one regularly for certain and rotating speed, the moment of torsion that motor 10 produces is embodied as carries out time of ignition SA _ACTFunction.Therefore, if actual charging efficiency Ec and actual rotational speed Ne are determined, then can calculate the implementation time of ignition SA corresponding with the Engine torque of wish output _ACTBy this method, to being acquisition IGNITION CONTROL target torque Pi _TGTDesired implementation time of ignition SA _ACTDesired value carry out computing.

To this, in the control of air amount amount, with air inlet control target torque Pi _ETVMake the desired value of the Engine torque that can be controlled to guarantee by the aperture of throttle valve 23, calculate the desired value of air quantity in the cylinder, the desired value of air quantity is to make for motor 10 to produce this air inlets control target torque Pi in this cylinder _ETVAir quantity in the cylinder that necessary sufficient combustion reaction occurs.In the present embodiment, use the conduct control be equivalent to air quantity in the cylinder with the desired value of the actual charging efficiency Ec of parameter, be target charging efficiency Ec _TGT

On the other hand, the Engine torque that produces along with the combustion reaction in the cylinder, its thermal efficiency according to motor 10 changes.Therefore, at target charging efficiency Ec _TGTCalculating process in, with the thermal efficiency of motor 10 with air inlet control target torque Pi _ETVBe converted into the torque value under the standard conditions, and come computing target charging efficiency Ec with the moment of torsion after converting _TGTHere, so-called standard conditions refer to that air fuel ratio is that chemically correct fuel, air amount do not contain EGR gas, time of ignition is the combustion condition of MBT.Herein, the numerical value of the used thermal efficiency is not according to the implementation time of ignition SA that calculates that transports in time of ignition control _ACTAnd calculate, but according to the target charging efficiency Ec that in the control of air amount amount, in the execution cycle till last time, calculates _TGTCalculate.Therefore, target charging efficiency Ec _TGTWith implementation time of ignition SA _ACTDivide opening operation.

This is because the implementation time of ignition SA that calculates in time of ignition control _ACTIt is according to the actual charging efficiency Ec of motor 10 and the cause of computing.Actual charging efficiency Ec is based on sensor values, and the numerical value of this actual charging efficiency Ec is the target charging efficiency Ec that calculates before the actual time point that obtains in motor 10 as basis _TGTThe result of control throttle valve 23 and be actual detection.Actual charging efficiency Ec is with respect to this target charging efficiency Ec _TGTRetard time comprise these controls of computing and accept and target charging efficiency Ec with time of parameters and throttle valve 23 _TGTAfter the corresponding control signal to throttle opening driving lag time till the execution etc. practically.

Therefore, when according to carrying out time of ignition SA _ACTAnd during calculating thermal efficiency, the operating condition of the motor 10 that this thermal efficiency reflects and produce with the operating condition of the motor 10 of from then on wish control of this thermal efficiency deviates from more greatly, when the operation point of motor changes, just might make to the convergence as the engine running point of target to descend.

Therefore, in this engine controlling unit 1, adopt the target charging efficiency Ec that in the control of air amount amount, calculates _TGTObtain thermal efficiency K _Pi, make it be reflected as the target charging efficiency Ec that recomputates _TGTNumerical value.In addition, in the present embodiment, as the parameter of the thermal efficiency that is equivalent to motor 10, use coefficient of thermal efficiency K _Pi

[3. control gear structure]

As shown in Figure 1, at the input side of engine controlling unit 1, be connected with intake manifold pressure sensor 31, atmosphere pressure sensor 32, air flow sensor 33, cooling water temperature sensor 34, engine rotary speed sensor 35, engine oil temperature sensor 36, accelerator open degree sensor 37 and external air temperature sensor 38.In addition, at the outlet side of engine controlling unit 1, the control object that is connected with the control of moment of torsion benchmark is spark plug 13, sparger 18, throttle valve 23, reflux valve 28 etc.

Be provided with target torque operational part 2, time of ignition control device 3, target charging efficiency operational part 4, air inflow control device 5, desired value operational part 6 and coefficient of thermal efficiency operational part 7 at this engine controlling unit 1.Each function of these target torque operational parts 2, time of ignition control device 3, target charging efficiency operational part 4, air inflow control device 5, desired value operational part 6 and coefficient of thermal efficiency operational part 7 both can be realized by electronic circuit (hardware), also can make and be programmed the software that forms, or with the part in these functions be made as hardware, other parts are made as the function of making software.

[3-1. target torque operational part]

Target torque operational part 2 carries out computing to the target torque of moment of torsion benchmark control in the execution cycle of regulation.Here, at first come four kinds of computings to require moment of torsion according to the desired moment of torsion of driver, the desired moment of torsion of external control system etc., the operating condition of motor 10 is that target torque requires to come the select target moment of torsion in the middle of the moment of torsion from these four kinds.So-called four kinds require moment of torsion, are throttle requirement moment of torsion Pi _APS, idling requires moment of torsion Pi _NeFB, responsiveness is not identical two kinds require moment of torsion (IGNITION CONTROL be with requiring moment of torsion Pi _{EXT_SA}, air inlet controls with requiring moment of torsion Pi _EXT).

Throttle requires moment of torsion Pi _NeFBBeing for keeping the desired moment of torsion of idling speed, for example, is according to accelerator open degree A _PSWith negative pressure (the barometric pressure P that produces in actual rotational speed Ne, the intake manifold 20 _BP-downstream pressure P _IM), external air temperature A _T, oil temperature O _T, coolant water temperature W _TDeng coming computing.In addition, throttle requires moment of torsion Pi _APSMainly be throttle operation with the driver corresponding require moment of torsion, namely be and the moment of torsion of acceleration request to using.Herein, according to accelerator open degree A _PSAnd actual rotational speed Ne comes computing throttle requirement moment of torsion Pi _APS

IGNITION CONTROL is with requiring moment of torsion Pi _{EXT_SA}And air inlet control is with requiring moment of torsion Pi _EXTBe the moment of torsion that requires from the external loading device, require moment of torsion Pi from throttle as required _APSSwitch and use the moment of torsion that is required.In the middle of them, IGNITION CONTROL is with requiring moment of torsion Pi _{EXT_SA}It is the moment of torsion that in the time of ignition control of spark plug 13, uses.Time of ignition control, it is shorter that it implements the rear time-delay till motor 10 generation moments of torsion of control in reality, is the high control of responsiveness.But the amplitude of the moment of torsion that can be controlled to adjust by time of ignition is less.

On the other hand, air inlet control is with requiring moment of torsion Pi _EXTTo utilize used moment of torsion in the air amount amount control that the throttle opening adjustment of throttle valve 23 carries out.Air amount amount control, its after reality is implemented control to motor 10 produce that time-delay till the moments of torsion is long, it is to compare the slightly poor control of responsiveness with time of ignition control.But the Amplitude Ratio of the moment of torsion that can be controlled to adjust by the air amount amount is large by the amplitude of the moment of torsion that time of ignition is controlled to adjust.Requiring moment of torsion with these four kinds, 2 pairs of target torque as two kinds of control targets of target torque operational part, is IGNITION CONTROL target torque Pi _TGTWith air inlet control target torque Pi _ETVCarry out computing.

The calculation process of Fig. 3 illustration target torque operational part 2.Target torque operational part 2 is provided with the first selection portion 2a, the second selection portion 2b and air inlet hysteresis correction portion 2c.The first selection portion 2a with IGNITION CONTROL with requiring moment of torsion Pi _{EXT_SA}, throttle requires moment of torsion Pi _APSAnd idling requires moment of torsion Pi _NeFBIn any one be chosen as the desired value of the moment of torsion that IGNITION CONTROL uses.In addition, the second selection portion 2b controls air inlet with requiring moment of torsion Pi _EXT, throttle requires moment of torsion Pi _APSAnd idling requires moment of torsion Pi _NeFBIn any one be chosen as the desired value of the moment of torsion of air inlet control usefulness.

These first selection portions 2a, the second selection portion 2b, according to such as from the torque demand of external control system have or not with motor 10 whether idle running etc. information and with time of ignition control, air inflow control is selected respectively should be as the torque value of target.The torque value of being selected by the first selection portion 2a is as IGNITION CONTROL target torque Pi _TGTAnd be passed to time of ignition control device 3.On the other hand, the torque value of being selected by the second selection portion 2b is passed to air inlet hysteresis correction portion 2c.

When air inlet hysteresis correction portion 2c controls used target torque in the calculating air inflow, carry out with throttle valve 23 to correction computing corresponding to the air inlet hysteresis of cylinder 19.Herein, to the torque value of being selected by the second selection portion 2b implement to lag behind process and the simulation air inlet reply lag behind and numerical operation be air inlet control target torque Pi _ETVThe method that the hysteresis of concrete air inlet hysteresis correction portion 2c is processed can be considered multiple according to the control form of throttle valve 23.For example, also can process by the torque value inputted being implemented once lag behind, second order lag processes, thereby generate the track of wanting the moment of torsion change that realizes.As easy method, as long as will multiply by the numerical value that the regulation filtration coefficient forms and add input value from the lag behind output value of correction portion 2c and difference to the input value of air inlet hysteresis correction portion 2c of air inlet.In addition, in the situation that the air inlet hysteresis characteristic changes according to the operating state of variable valve actuator for air, also can increase according to this operating state and make air inlet control target torque Pi _ETVThe computing that change postpones.The operating state of variable valve actuator for air comprises valve lift amount and valve timing and the lap etc. of intake valve 14, exhaust valve 15.The air inlet control target torque Pi of computing herein _ETVNumerical value be passed to target charging efficiency operational part 4.

[3-2. time of ignition control device]

Time of ignition control device 3 (carrying out the time of ignition arithmetic element) is according to the IGNITION CONTROL target torque Pi by 2 computings of target torque operational part _TGTAnd implement time of ignition control at the execution cycle of regulation.The calculation process of Fig. 4 illustration time of ignition control device 3.Time of ignition control device 3 is provided with actual charging efficiency operational part 3a, MBT operational part 3b, actual MBT torque calculation unit 3c, igniting index operational part 3d, hysteresis operational part 3e and the 3f of subtraction section.

Actual charging efficiency operational part 3a is according to the charge flow rate Q by 23 ones of throttle valve _INAnd be actual charging efficiency Ec with the charging efficiency computing of reality.So-called charging efficiency is: the volume standard that will be filled in the air in the cylinder 19 during an aspirating stroke changes into behind the gas volume under the standard state (25 ℃, 1 air pressure) divided by volume of cylinder V _ENGIn addition, a so-called aspirating stroke is that for example piston 16 moves to a stroke till the lower dead center from top dead center.Here, for the cylinder 19 of control object, by during the aspirating stroke before just by air flow sensor 33 detected charge flow rate Q _INTotal come air quantity in the actual cylinder that is inhaled into control object 19 of computing, the actual charging efficiency Ec of computing.The actual charging efficiency Ec of computing herein is passed to MBT operational part 3b and actual MBT torque calculation unit 3c.

MBT operational part 3b is according to by the actual charging efficiency Ec of actual charging efficiency operational part 3a computing and actual rotational speed Ne the MBT time of ignition (also referred to as MBT, Minmum spark advance for Best Torque) that produces Maximum Torque being carried out computing.Below, SA is used as the symbol that represents time of ignition.In addition, in the time of the MBT time of ignition among the indication fire moment SA, be designated as SA _MBTThe corresponding relation of the moment of torsion that MBT operational part 3b will be for example produces by actual charging efficiency Ec, time of ignition SA and chemically correct fuel is stored as figure and the mathematical expression of every actual rotational speed Ne, comes computing MBT time of ignition SA with it _MBTThe MBT time of ignition SA of computing here _MBTNumerical value be passed to the 3f of subtraction section.

Actual MBT torque calculation unit 3c is with actual charging efficiency Ec and actual rotational speed Ne by actual charging efficiency operational part 3a computing, to be maximum actual torque Pi in cylinder 19 interior Maximum Torque (that is to say, time of ignition is set as the moment of torsion that is produced in the situation of MBT take the actual charging efficiency Ec) computings that can produce of control object _{ACT_MBT}Actual MBT torque calculation unit 3c comes the maximum actual torque Pi of computing with for example identical with MBT operational part 3b figure and mathematical expression _{ACT_MBT}The maximum actual torque Pi of computing here _{ACT_MBT}Be passed to igniting index operational part 3d.

Igniting index operational part 3d will be by the IGNITION CONTROL target torque Pi of target torque operational part 2 computings _TGTWith the maximum actual torque Pi by actual MBT torque calculation unit 3c computing _{ACT_MBT}The ratio computing be igniting index K.Here, according to by air flow sensor 33 detected charge flow rate Q _INAnd the computing IGNITION CONTROL is the ratio of degree how with moment of torsion with respect to the Maximum Torque that can produce.In addition, in the igniting index operational part 3d of present embodiment, even be required to surpass maximum actual torque Pi _{ACT_MBT}The IGNITION CONTROL of such surplus target torque Pi _TGT, for making time of ignition than MBT time of ignition SA _MBTDo not produce advance angle, the numerical value of igniting index K also will be limited in the scope (0≤K≤1) below 1.The numerical value of the igniting index K of computing here is passed to hysteresis operational part 3e.

Hysteresis operational part 3e is take MBT as benchmark, and the hysteresis R (the retardation angle amount of time of ignition) corresponding with igniting index K to size carries out computing.To the light a fire corresponding relation of index K and hysteresis R of hysteresis operational part 3e is stored as figure and the mathematical expression of every actual rotational speed Ne, comes computing hysteresis R with this figure and mathematical expression.In addition, said hysteresis R is the numerical value take MBT as benchmark here, have igniting index K (0≤K≤1) more close to 1, hysteresis R is just more close to zero characteristic.In addition, hysteresis R has larger with actual rotational speed Ne and characteristic that increase.The hysteresis R of computing here is passed to the 3f of subtraction section.

The 3f of subtraction section is according to the computing implementation time of ignition SA by the hysteresis R of hysteresis operational part 3e computing _ACTHere, for example from the MBT time of ignition SA by MBT operational part 3b computing _MBTIn deduct numerical value behind the hysteresis R by computing for carrying out time of ignition SA _ACTThe implementation time of ignition SA of computing here _ACTTo produce and IGNITION CONTROL target torque Pi _TGTThe time of ignition of corresponding moment of torsion.Time of ignition control device 3 output control signals so that the spark plug 13 of cylinder 19 that is located at control object at this implementation time of ignition SA _ACTLight a fire, carry out time of ignition control.

[3-3. target charging efficiency operational part]

Target charging efficiency operational part 4 (target charging efficiency arithmetic element) is used for the target charging efficiency Ec of air amount amount control in the execution cycle computing of regulation _TGTSo-called target charging efficiency Ec _TGTCharging efficiency corresponding to target empty tolerance in the cylinder 19 that is and should imports control object.Here, at this of motor 10 constantly with the coefficient of thermal efficiency K that represents as the thermal efficiency of the operation point of target _Pi, will control with the generation air inlet and use target torque Pi _ETVCharging efficiency computing corresponding to required air quantity is target charging efficiency Ec _TGT

The calculation process of Fig. 5 illustration target charging efficiency operational part 4.Target charging efficiency operational part 4 is provided with standard conditions air inlet target torque operational part 4a, conversion coefficient operational part 4b, moment of torsion changeover part 4c and memory section 4d.

Standard conditions air inlet target torque operational part 4a is to the air inlet control target torque Pi by 2 computings of target torque operational part _ETVBe converted into the standard conditions air inlet target torque Pi of the torque value under the standard conditions _{ETV_STD}Carry out computing.Here, air inlet control target torque Pi _ETVDivided by coefficient of thermal efficiency K _PiAnd the numerical value that gets is standard conditions air inlet target torque Pi by computing _{ETV_STD}Torque value under the so-called standard conditions refers to that air fuel ratio is chemically correct fuel and the torque value when by MBT the air amount that does not contain EGR gas being lighted a fire.At this moment, coefficient of thermal efficiency K _PiBe K _Pi=1.

In addition, so-called coefficient of thermal efficiency K _PiBe the control parameter suitable with the thermal efficiency of motor 10, its expression is that how ratio ground increases or reduces by the moment of torsion that the combustion reaction in the cylinder 19 produces with respect to the moment of torsion that produces under standard conditions.In addition, coefficient of thermal efficiency K _PiNumerical value use the numerical value gone out by coefficient of thermal efficiency operational part 7 computings described later.The standard conditions air inlet target torque Pi of computing here _{ETV_STD}Numerical value be passed to conversion coefficient operational part 4b.

Conversion coefficient operational part 4b is according to actual rotational speed Ne and standard conditions air inlet target torque Pi _{ETV_STD}Come computing to be used for torque value is converted to the conversion coefficient Z of charging efficiency (air quantity) value.Conversion coefficient operational part 4b is actual rotational speed Ne and standard conditions air inlet target torque Pi for example _{ETV_STD}And the relational storage between the conversion coefficient Z comes computing conversion coefficient Z for figure and mathematical expression with it.The numerical value of the conversion coefficient Z of computing here is passed to moment of torsion changeover part 4c.

Moment of torsion changeover part 4c is with standard conditions air inlet target torque Pi _{ETV_STD}Be target charging efficiency Ec divided by the numerical operation behind the conversion coefficient Z _TGTSo-called this target charging efficiency Ec _TGT, be and standard conditions air inlet target torque Pi _{ETV_STD}Corresponding charging efficiency.The target charging efficiency Ec of computing here ^TGTNumerical value be passed to memory section 4d.Memory section 4d is to the target charging efficiency Ec by moment of torsion changeover part 4c computing _TGTStore.Here, not only be stored in the target charging efficiency Ec of current execution cycle computing _TGT, but also be stored in the lump the target charging efficiency Ec of execution cycle computing in the past _TGTHere the target charging efficiency Ec that stores _TGTNumerical value, be at least more than one except currency.In the present embodiment, to target charging efficiency Ec _TGTCurrency and these two stored situations of the numerical value of last time carry out illustration.

These target charging efficiencies Ec _TGTIn currency be used as by air amount amount control with should import cylinder 19 in desired value corresponding to air quantity.On the other hand, the numerical value of last time is used for coefficient of thermal efficiency K _PiComputing.Below, the numerical value of last time of target charging efficiency is designated as Ec _{TGT_PRE}

[3-4. air inflow control device]

Air inflow control device 5 usefulness are by the target charging efficiency Ec of target charging efficiency operational part 4 computings _TGT, implement the control of air amount amount at the execution cycle of regulation.The calculation process of Fig. 6 illustration air inflow control device 5.Air inflow control device 5 is provided with air quantity operational part 5a, intake advance compensation section 5b, target flow operational part 5c, flow velocity operational part 5d and throttle opening operational part 5e in the target cylinder.

Air quantity operational part 5a carries out such computing in the target cylinder: will be by the target charging efficiency Ec of target charging efficiency operational part 4 computings _TGTConvert the desired value Q that imports the charge flow rate (air quantity of an aspirating stroke) in the cylinder 19 to _CcaThe used numerical value of the conversion here is target charging efficiency Ec _TGTCurrency.

As mentioned above, charging efficiency is divided by volume of cylinder V with the gas volume (volume of per unit stroke) in the cylinder 19 under the standard state _ENGThe numerical value that obtains.Therefore, the gas volume in the cylinder under the standard state 19 passes through volume of cylinder V _ENGMultiply by charging efficiency and calculate.

Here, according to for example predefined target charging efficiency Ec _TGTWith desired value Q _CcaCorresponding diagram and mathematical expression etc. obtain desired value Q _CcaIn addition, consider the situation that the suction pressure that imports in the cylinder 19 and temperature are different from standard state, but also computing will be according to intake temperature (external air temperature A _T) and downstream pressure P _IMDesired value Q after (air-distributor pressure), density of the induced air etc. and the correction factor set add _CcaThe desired value Q of computing here _CcaNumerical value be passed to intake advance compensation section 5b.

Intake advance compensation section 5b implements the opposite processing of hysteresis processing implemented with air inlet hysteresis correction portion 2c by target torque operational part 2.Namely, operation content before ratio is gone back by intake advance compensation section 5b input is the computing about the moment of torsion of each cylinder 19 of motor 10 and air quantity etc., relatively, the later operation content of intake advance compensation section 5b is the computing relevant with the air inlet of passing through throttle valve 23.Here, according to the Air intake characteristics of motor 10, intake manifold 20, knock out drum 21, throttle valve 23 etc., computing is to desired value Q _CcaImplemented the second desired value Q after the inverse operation (intake advance computing) that air inlet lags behind _Cca2

In addition, the method for concrete intake advance computing is arbitrarily.For example, can consider to adopt desired value Q _CcaThe gradient of variation in past be considered to after this, also be maintained the method for union extrapolated value.As easy method, as long as with desired value Q _CcaThe numerical value that multiply by behind the filtration coefficient of regulation of the variable quantity from the numerical value of last time to this numerical value add that this sub-value gets final product.The second desired value Q of computing here _Cca2Be passed to target flow operational part 5c.

Target flow operational part 5c is according to the second desired value Q that is transmitted by intake advance compensation section 5b _Cca2And to the target flow Q by throttle valve 23 air inlets _{TH_TGT}Carry out computing.The second desired value Q _Cca2The numerical value corresponding with the air quantity that in an aspirating stroke, should pass through throttle valve 23.Therefore, the second desired value Q here _Cca2Numerical value is changed according to actual rotational speed Ne, the target flow Q of union time per unit _{TH_TGT}The target flow Q of computing here _{TH_TGT}Be passed to throttle opening operational part 5e.

Flow velocity operational part 5d carries out computing to the flow velocity V of the air amount by throttle valve 23.Here, according to the downstream pressure P of throttle valve 23 _IMWith respect to upstream pressure P _THURatio (P _IM/ P _THU) and computing flow velocity V.Flow velocity operational part 5d comes computing flow velocity V with figure and the mathematical expression for example the variation of the caused flow velocity V of front and back pressure ratio of 23 ones of throttle valve stipulated.The flow velocity V of computing here is passed to throttle opening operational part 5e.

Throttle opening operational part 5e is according to the target flow Q by target flow operational part 5c computing _{TH_TGT}With the target opening area S of computing throttle valve 23 by the flow velocity V of flow velocity operational part 5d computing.Mass velocity M when for example as shown in Figure 6, calculating flow velocity V is multiplied by critical condition (flow velocity V is Sonic condition) _MACHAfter numerical value, target opening area S is with target flow Q _{TH_TGT}Obtain divided by this numerical value.Mass velocity M _MACHTo consider the air density change that temperature causes and the numerical value of figuring in, for example, according to by external air temperature sensor 38 detected external air temperature A _TWith upstream pressure P _THUAnd set.

In addition, throttle opening operational part 5e exports control signals so that the actual aperture area of throttle valve 23 equates with target opening area S to throttle valve 23.For example, according to predefined target opening area S and target aperture voltage E _LCorresponding diagram and mathematical expression etc. and computing target aperture voltage E _L, this target aperture voltage E _LBe output to throttle valve 23 as control signal.Target opening area S and target aperture voltage E _LRelation, stipulate according to structure, shape and the kind etc. of throttle valve 23.

Then, throttle valve 23 is accepted to control throttle opening, realize target opening area S from the control signal of throttle opening 5e.This target opening area S can be described as and will make and air inlet control target torque Pi _ETVThe air that corresponding moment of torsion produces imports the opening area in the cylinder 19.So, 5 pairs of throttle valve openings of air inflow control device are controlled, and carry out the control of air amount amount, with realize target charging efficiency Ec in the cylinder 19 of control object _TGT

[3-5. desired value operational part]

Desired value operational part 6 is not to be operation point in the current operating condition of motor 10 as the control target, but with target charging efficiency Ec by 4 computings of target charging efficiency operational part _TGTCorresponding operation point is to the calculating thermal efficiency COEFFICIENT K _PiWith control carry out computing with parameter.This target charging efficiency Ec _TGTAs shown in Figure 5, be according to actual rotational speed Ne and air inlet control target torque Pi _ETVAnd the numerical value after the computing.Therefore, when have with engine rotary speed and output torque be configured in the coordinate plane (plane of so-called pieces engine performance curve figure) of transverse axis and the longitudinal axis, when the operation point of motor 10 is defined as point on this coordinate plane, said " with target charging efficiency Ec here _TGTCorresponding operation point " the coordinate composition target charging efficiency Ec that just has been equivalent to computing _TGTThe actual rotational speed Ne of time point and air inlet control target torque Pi _ETVBelow, will with this target charging efficiency Ec _TGTCorresponding operation point is called the target operation point.

Desired value operational part 6 is not to come the calculating thermal efficiency COEFFICIENT K according to sensor values and actual charging efficiency Ec that the current operating condition to motor 10 detects _Pi, but according to target charging efficiency Ec _TGTCome the calculating thermal efficiency COEFFICIENT K _PiHere, at coefficient of thermal efficiency K _PiComputational process in three kinds of control parameters of computing.As shown in Figure 1, desired value operational part 6 be provided with target ignition constantly operational part 6A, target air-fuel ratio operational part 6B and target EGR lead operational part 6C, three kinds of control with parameter by separately operational part computing.

In addition, as shown in Figure 5, coefficient of thermal efficiency K _PiFor computing target charging efficiency Ec _TGTThe control parameter, coefficient of thermal efficiency K _PiAnd target charging efficiency Ec _TGTCalculation process circulate by desired value operational part 6.That is the target charging efficiency Ec that, obtains at the execution cycle of last time _{TGT_PRE}Be used for calculating this coefficient of thermal efficiency K _Pi, the target charging efficiency Ec in the execution cycle of this that obtains accordingly _TGTBe used for calculating at the used coefficient of thermal efficiency K of the execution cycle of next time _Pi

[the 3-5-1. target ignition is operational part constantly]

Target ignition moment operational part 6A (target ignition is arithmetic element constantly) is constantly SA of target ignition with the time of ignition computing of target operation point _{MAIN_TGT}This target ignition is SA constantly _{MAIN_TGT}, not using this point in actual ignition is controlled constantly is to be different to carry out time of ignition SA _ACT.That is, target ignition moment SA _{MAIN_TGT}For the calculating thermal efficiency COEFFICIENT K _PiTime of ignition, be for the time of ignition (the favourable time of ignition of air amount amount control usefulness) that calculates the air amount amount in the cylinder 19.

Fig. 7 illustration target ignition is the calculation process of operational part 6A constantly.Target ignition constantly operational part 6A is provided with the first basic ignition constantly operational part 61a, the second basic ignition moment operational part 61b, interpolation arithmetic unit 62, environmental conditions correction portion 63, idling correction portion 64 and vent systems correction portion 65.

The first basic ignition constantly operational part 61a, the second basic ignition constantly operational part 61b respectively according to the numerical value Ec of last time of target charging efficiency _{TGT_PRE}With actual rotational speed Ne and computing the first time of ignition A, the second time of ignition B.The first time of ignition A is that the charging efficiency when cylinder 19 interior air is the numerical value Ec of last time _{TGT_PRE}And when using high-octane fuel (high-knock rating gasoline), the time of ignition that requires for obtaining actual rotational speed Ne.For the first basic ignition moment operational part 61a, prepare for example predefined actual rotational speed Ne, target charging efficiency Ec _TGTAnd the corresponding diagram of the first time of ignition A and mathematical expression etc., obtain the first time of ignition A according to this corresponding diagram and mathematical expression etc.

On the other hand, the second time of ignition B is the time of ignition the when fuel condition in the computational process of the first time of ignition A is changed to common octane fuel (regular price gasoline).The second basic ignition constantly operational part 61b has for example predefined actual rotational speed Ne and target charging efficiency Ec _TGTAnd the corresponding diagram of the second time of ignition B and mathematical expression etc., obtain the second time of ignition B according to this corresponding diagram and mathematical expression etc.Be passed to interpolation arithmetic unit 62 by the first time of ignition A of constantly constantly operational part 61b computing of operational part 61a, the second basic ignition of the first basic ignition, the separately numerical value of the second time of ignition B.

62 pairs of interpolation arithmetic unit are with pinking learning value K _NInterpolation time of ignition C behind interpolation the first time of ignition A and the second time of ignition B carries out computing.Pinking learning value K _NBe to make time of ignition be suitable for the learning value of the reduction value that point of detonation that the octane value according to gasoline changes uses, learnt at any time by not shown pinking study section.Illustration is come computing interpolation time of ignition C according to following mathematical expression 1 among Fig. 7.In addition, pinking learning value K _NDefinitional domain be (0≤K more than 0, below 1 _N≤ 1), it has larger and the characteristic that time of ignition is moved to the advance angle direction of this numerical value.

By using pinking learning value K _NTo carrying out the computing of interpolation between the first time of ignition A and the second time of ignition B, the interpolation time of ignition C that then obtains as its result is exactly the time of ignition corresponding with the natural fuel octane value that is supplied in motor 10.The numerical value of the interpolation time of ignition C of computing here is passed to environmental conditions correction portion 63.

Mathematical expression 1:

C=AK _N+ B (1-K _N) (formula 1)

Environmental conditions correction portion 63 increases the correction of the time of ignition corresponding with environmental conditions that relates to motor 10 running environment.Here, add or be multiplied by numerical value Ec according to the last time of target charging efficiency _{TGT_PRE}, coolant water temperature W _TAnd external air temperature A _TAnd the reduction value of setting is revised interpolation time of ignition C.Concrete method for correcting is arbitrarily.For example, because coolant water temperature W _TWith external air temperature A _TMore lowly more be difficult to produce pinking, therefore, interpolation time of ignition C moved to the advance angle direction.Here the numerical value of the interpolation time of ignition C that revises is passed to idling correction portion 64.

Reduction value when idling correction portion 64 gives the idle running of motor 10.Here, when the idling condition of motor 10 is set up, give the reduction value that when being false than idling condition interpolation time of ignition C is moved to the retardation angle direction.The degree of ignition retard amount that is equivalent to hysteresis that torque reserve amount when thus, guaranteeing idle running is used is reflected as interpolation time of ignition C.Here the numerical value of the interpolation time of ignition C that revises is passed to vent systems correction portion 65.

65 enforcements of vent systems correction portion are located at Exhaust gas purifying device and the desired time of ignition correction of catalyst-assembly of the vent systems of motor 10.Here, improve the degree of ignition retard amount of usefulness for exhaust performance when sening as an envoy to cold start-up and make heat up the rapidly degree of ignition retard amount of usefulness of catalyst-assembly.The numerical value that reflects the interpolation time of ignition C of these retardation angle amounts is as target ignition moment SA _{MAIN_TGT}And be passed to coefficient of thermal efficiency operational part 7.

[3-5-2. target air-fuel ratio operational part]

Target air-fuel ratio operational part 6B (target air-fuel ratio arithmetic element) is target air-fuel ratio AF with the air fuel ratio computing of target operation point _TGTThis target air-fuel ratio AF _TGTBeing obsolete control parameter in the fuel control of reality, is for the calculating thermal efficiency COEFFICIENT K _PiAir fuel ratio, be for the air fuel ratio (the favourable air fuel ratio of air amount amount control usefulness) of calculating the air amount amount in the cylinder 19.

The calculation process of Fig. 8 illustration target air-fuel ratio operational part 6B.Target air-fuel ratio operational part 6B is provided with the first basic air fuel ratio operational part 66a, the second basic air fuel ratio operational part 66b, interpolation arithmetic unit 67, feedback modifiers section 68 and vent systems correction portion 69.In addition, Fig. 8 example illustrates and replaces target air-fuel ratio AF _TGTAnd computing target air-fuel ratio COEFFICIENT K _{AF_TGT}The target air-fuel ratio COEFFICIENT K _{AF_TGT}Be and target air-fuel ratio AF _TGTCorresponding control parameter makes the coefficient take chemically correct fuel as benchmark one to one.That is, as target air-fuel ratio AF _TGTAF _TGT=14.7 o'clock, the target air-fuel ratio COEFFICIENT K _{AF_TGT}Be K just _{AF_TGT}=1.

The first basic air fuel ratio operational part 66a, the second basic air fuel ratio operational part 66b are respectively according to the numerical value Ec of last time of target charging efficiency _{TGT_PRE}With actual rotational speed Ne and computing the first air fuel ratio coefficient D and the second air fuel ratio coefficient F.The charging efficiency of the air in cylinder 19 is the numerical value Ec of last time _{TGT_PRE}And when having used antiknock gasoline (high-knock rating gasoline), the first air fuel ratio coefficient D be with for obtaining the corresponding coefficient of air fuel ratio that actual rotational speed Ne requires.The first basic air fuel ratio operational part 66a has for example predefined actual rotational speed Ne, target charging efficiency Ec _TGTAnd the corresponding diagram of the first air fuel ratio coefficient D and mathematical expression etc., obtain the first air fuel ratio coefficient D according to this corresponding diagram and mathematical expression etc.

On the other hand, the second air fuel ratio coefficient E is the corresponding coefficient of air fuel ratio when the fuel condition in the computational process of the first air fuel ratio coefficient D is changed to common octane fuel (regular price gasoline).The second basic air fuel ratio operational part 66b has for example predefined actual rotational speed Ne, target charging efficiency Ec _TGTAnd the corresponding diagram of the second air fuel ratio coefficient E and mathematical expression etc., obtain the second air fuel ratio coefficient E according to this corresponding diagram and mathematical expression etc.Be passed to interpolation arithmetic unit 67 by the first air fuel ratio coefficient D of the first basic air fuel ratio operational part 66a, the second basic air fuel ratio operational part 66b computing and the separately numerical value of the second air fuel ratio coefficient E.

Interpolation arithmetic unit 67 is identical with aforesaid interpolation arithmetic unit 62, to pinking learning value K _NInterpolation air fuel ratio coefficient F behind interpolation the first air fuel ratio coefficient D and the second air fuel ratio coefficient E carries out computing.Here used pinking learning value K _NBe and used identical of interpolation arithmetic unit 62.Fig. 8 illustration is according to following formula 2 and computing interpolation air fuel ratio coefficient F.By using pinking learning value K _NTo carrying out the computing of interpolation between the first air fuel ratio coefficient D and the second air fuel ratio coefficient E, the interpolation air fuel ratio coefficient F that then obtains as its result is the coefficient of the air fuel ratio corresponding with the natural fuel octane value that is supplied in motor 10.The numerical value of the interpolation air fuel ratio coefficient F of computing here is passed to feedback modifiers section 68.

Mathematical expression 2:

F=DK _N+ E (1-K _N) (formula 2)

The setting value of interpolation air fuel ratio coefficient F when the air-fuel ratio feedback with motor 10 of feedback modifiers section 68 turns round is F=1.Generally, fuel injection amount is adjusted to automatically when air-fuel ratio feedback turns round: the burning and gas-exhausting of the result behind the 26 interior mixture combustions of firing chamber is equivalent to the burning under theoretical air fuel ratio.On the other hand, because the numerical value of interpolation air fuel ratio coefficient F also is the coefficient take chemically correct fuel as benchmark, therefore, the numerical value of the interpolation air fuel ratio coefficient F when the air-fuel ratio feedback here turns round is set to F=1, is passed to vent systems correction portion 69.In addition, not air-fuel ratio feedback when running, intactly be passed to vent systems correction portion 69 by the numerical value of the interpolation air fuel ratio coefficient F of interpolation arithmetic unit 67 computings.

Vent systems correction portion 69 implements to be located at Exhaust gas purifying device and the desired air-fuel ratio correction of catalyst-assembly of motor 10 vent systems.Here, give to make the rapid intensification of catalyst-assembly reduce the air-fuel ratio correction amount of the discharge usefulness of unburned gas composition by the oxygen concentration (fuel concentration is descended) that improves a little in the exhaust after for example burning.The numerical value that reflects the interpolation air fuel ratio coefficient F of this reduction value is as the target air-fuel ratio COEFFICIENT K _{AF_TGT}And be passed to coefficient of thermal efficiency operational part 7.

[3-5-3. target EGR leads operational part]

Target EGR leads operational part 6C (target exhaust reflux ratio arithmetic element), and the EGR of target operation point is led (exhaust gas recirculation rate) computing is that target EGR leads R _{EGR_TGT}Target EGR leads R _{EGR_TGT}Being obsolete control parameter in actual EGR control, is for the calculating thermal efficiency COEFFICIENT K _PiEGR lead, be that the EGR for the air amount amount of computing in the cylinder 19 leads (the favourable EGR of air amount amount control usefulness leads).

Fig. 9 illustration target EGR leads the calculation process of operational part 6C.Target EGR leads the numerical value Ec of operational part 6C according to the last time of target charging efficiency _{TGT_PRE}With actual rotational speed Ne and computing target EGT leads R _{EGR_TGT}Here, operational part 61a is identical with the first basic air fuel ratio operational part 66a constantly with aforesaid the first basic ignition, obtains target EGR according to predefined figure and mathematical expression etc. and leads R _{EGR_TGT}Here the target EGR that obtains leads R _{EGR_TGT}Numerical value be passed to coefficient of thermal efficiency operational part 7.

[3-6 coefficient of thermal efficiency operational part]

Coefficient of thermal efficiency operational part 7 (thermal efficiency arithmetic element) is according to the target ignition moment SA by 6 computings of desired value operational part _{MAIN_TGT}, the target air-fuel ratio COEFFICIENT K _{AF_TGT}(target air-fuel ratio AF _TGT) and target reflux ratio coefficients R _{EGR_TGT}(target reflux ratio EGR _TGT) and computing coefficient of thermal efficiency K _PiHere, the size coefficient of thermal efficiency K corresponding with hysteresis that begin from the MBT of the time of ignition of target operation point of computing _Pi, and it is by the target air-fuel ratio COEFFICIENT K _{AF_TGT}And target reflux ratio coefficients R _{EGR_TGT}Revise the coefficient of thermal efficiency K that computing is final _PiThe coefficient of thermal efficiency K of computing here _PiBe imported into the standard conditions air inlet target torque operational part 4a of aforesaid target charging efficiency operational part 4, be used to the air amount amount control of next execution cycle.

The calculation process of Figure 10 illustration coefficient of thermal efficiency operational part 7.Coefficient of thermal efficiency operational part 7 is provided with the 2nd MBT operational part 71, the second subtraction section 72, coefficient of thermal efficiency operational part 73, equivalent proportion efficiency factor operational part 74, EGR efficiency factor operational part 75 and multiplication calculating part.

The 2nd MBT operational part 71 is according to the numerical value Ec of the last time of target charging efficiency _{TGT_PRE}With actual rotational speed Ne and the target MBT time of ignition SA of computing target operation point _{MBT_TGT}Here, according to come computing target MBT time of ignition SA such as the identical figure of MBT operational part 3b and mathematical expression etc. _{MBT_TGT}Target MBT time of ignition SA _{MBT_TGT}Refer to the numerical value Ec when last time _{TGT_PRE}Corresponding air is inhaled into the time of ignition that cylinder 19 produces Maximum Torque when interior with actual rotational speed Ne.The target MBT time of ignition SA of computing here _{MBT_TGT}Be passed to the second subtraction section 72.

72 computings of the second subtraction section are from target MBT time of ignition SA _{MBT_TGT}In deduct by the target ignition of constantly operational part 6A computing of target ignition SA constantly _{MAIN_TGT}After the value of deducting Δ SA.This value of deducting Δ SA is equivalent to target MBT time of ignition SA _{MBT_TGT}Target ignition moment SA for benchmark _{MAIN_TGT}Hysteresis.Here the value of deducting of computing Δ SA is passed to coefficient of thermal efficiency operational part 73.

Coefficient of thermal efficiency operational part 73 is according to the value of deducting Δ SA and actual rotational speed Ne and computing coefficient of thermal efficiency K _PiCoefficient of thermal efficiency operational part 73 will the value of deducting Δ SA and actual rotational speed Ne and coefficient of thermal efficiency K _PiRelational storage be figure and mathematical expression, and with its computing coefficient of thermal efficiency K _PiThe value of deducting Δ SA is from target MBT time of ignition SA _{MBT_TGT}Beginning be equivalent to the numberical value of quantity that lags behind.In addition, when the hysteresis that begins from MBT is one regularly, the reduced rate as the moment of torsion that ignition lag was produced of benchmark during take MBT is certain, and is irrelevant with the size of air quantity.Therefore, as long as just can obtain specially coefficient of thermal efficiency K according to the value of deducting Δ SA and actual rotational speed Ne _PiThe coefficient of thermal efficiency K of computing here _PiBe passed to multiplication calculating part 76.

Equivalent proportion efficiency factor operational part 74 is according to the target air-fuel ratio COEFFICIENT K by target air-fuel ratio operational part 6B computing _{AF_TGT}And computing equivalent proportion efficiency factor K _{Pi_AF}Equivalent proportion efficiency factor K _{Pi_AF}To the coefficient of thermal efficiency K by 73 computings of coefficient of thermal efficiency operational part _PiRevise one of correction factor of usefulness.Equivalent proportion efficiency factor operational part 74 is with the target air-fuel ratio COEFFICIENT K _{AF_TGT}With equivalent proportion efficiency factor K _{Pi_AF}Relation pre-stored for figure and mathematical expression, with its computing equivalent proportion efficiency factor K _{Pi_AF}, and this numerical value is delivered to multiplication calculating part 76.

Equally, EGR efficiency factor operational part 75 leads R according to the target EGR that is led operational part 6C computing by target EGR _{EGR_TGT}And computing EGR efficiency factor K _{Pi_EGR}EGR efficiency factor operational part 75 leads R with target EGR _{EGR_TGT}With EGR efficiency factor K _{Pi_EGR}Relation pre-stored for figure and mathematical expression, with its computing EGR efficiency factor K _{Pi_EGR}, and this numerical value is delivered to multiplication calculating part 76.

Multiplication calculating part 76 will be to the coefficient of thermal efficiency K by 73 computings of coefficient of thermal efficiency operational part _PiBe multiplied by the equivalent proportion efficiency factor K by 74 computings of equivalent proportion efficiency factor operational part _{Pi_AF}With the EGR efficiency factor K by 75 computings of EGR efficiency factor operational part _{Pi_EGR}After numerical operation be final coefficient of thermal efficiency K _PiThis coefficient of thermal efficiency K _PiThe coefficient of thermal efficiency K of the target operation point of motor 10 _PiThe coefficient of thermal efficiency K of computing here _PiBe passed to target charging efficiency operational part 4.

[4. effect and effect]

So, adopt the engine controlling unit 1 of present embodiment, can obtain following such effect and effect.

(1) in above-mentioned engine controlling unit 1, according to the target charging efficiency Ec by execution cycle computing last time _{TGT_PRE}And the target ignition of the current execution cycle of computing SA constantly _{MAIN_TGT}, and by according to this target ignition SA constantly _{MAIN_TGT}And the thermal efficiency K of computing _PiCome computing should import air amount amount in the cylinder 19.Utilize this computing, no matter actual charging efficiency Ec is with respect to target charging efficiency Ec _TGTThe length of lag time, all can suitably control the air amount amount, when the operation point of motor changes, can be rapidly and accurately to the engine running point convergence as target.

In addition owing to can expect that the stable air amount amount that is not subjected to affect this lag time controls, therefore, drive long inexpensive electronically controlled throttle valve 23 lag time even if use, also can guarantee to control responsiveness and control stability, can reduce product cost and improve functional.

(2) in addition, in above-mentioned engine controlling unit 1, the target ignition of the target operation point of computing motor 10 SA constantly not only _{MAIN_TGT}, and computing is corresponding to target air-fuel ratio AF _TGTThe target air-fuel ratio COEFFICIENT K _{AF_TGT}Thus, can computing have considered that the octane value of fuel gives the coefficient of thermal efficiency K of impact of the thermal efficiency of motor 10 _PiTherefore, can further improve the control accuracy of air amount amount, when the operation point of motor changes, can improve to the convergence as the engine running point of target.

(3) in addition, in above-mentioned engine controlling unit 1, the target reflux ratio EGR of the target operation point of computing and motor 10 _TGTCorresponding target reflux ratio coefficients R _{EGR_TGT}Thus, but the thermal efficiency that just computing will be corresponding with the capacity of reflux of EGR gas changes the coefficient of thermal efficiency K after adding _PiTherefore, can further improve the control accuracy of air amount amount, when the operation point of motor changes, can improve to the convergence as the engine running point of target.

(4) in addition, at the target ignition of above-mentioned engine controlling unit 1 constantly among the operational part 6A, because according to the numerical value Ec of last time of target charging efficiency _{TGT_PRE}And the target ignition of computing target operation point moment SA _{MAIN_TGT}, therefore, can carry out continuously computing and the constantly computing of operational part 6A of target ignition of target charging efficiency operational part 4.Thus, can eliminate the time-delay of computing, the thermal efficiency variation in the time of engine running point being changed is reflected to the control of air amount amount to greatest extent, can improve the closure sensitivity that changes with respect to operation point.

(5) in addition, in moment of torsion benchmark control in the past, as shown in phantom in Figure 2, to be produced with respect to the control of air amount amount by the information of the actual charging efficiency Ec (amount of actual air for combustion) of time of ignition control time-delay to lag behind and bring the operating structure of impact, but in above-mentioned engine controlling unit 1, mutually independent enforcement of time of ignition control and the control of air amount amount, thus, be difficult to produce the contradiction in the control, the result can improve the controlled of motor.

[5. variation]

The variation of the control of being implemented by above-mentioned engine controlling unit 1 can be considered varied.For example, in the above-described embodiment, although illustration implement the moment of torsion benchmark control of the control of air amount amount and time of ignition control, also can make and implement simultaneously in addition time of ignition control and EGR measures the structure of control, variable valve actuator for air control etc.

In addition, in the above-described embodiment, although illustration according to the numerical value Ec of last time of target charging efficiency _{TGT_PRE}And computing coefficient of thermal efficiency K _Pi, but also can replace this structure, and according to the target charging efficiency Ec by the execution cycle computing of upper last time _TGTAnd computing coefficient of thermal efficiency K _Pi, perhaps, also available targets charging efficiency Ec _TGTThe numerical value of last time and the mean value of the numerical value of upper last time etc. and computing thermal efficiency K _PiAs long as use the control corresponding with target empty tolerance to come computing coefficient of thermal efficiency K with parameter _PiGet final product, this target empty tolerance is that at least in the past execution cycle calculates.How to use target empty tolerance in the past, can suitably change according to the desired responsiveness of the control operation of air amount amount and stability etc.In addition, in that to adopt movement speed be in the situation of electric control device at a high speed or adopting and drive lag time in the situation of long throttle valve 23, as long as select the operation method of the best according to their movement speed, response speed.

In addition, in the above-described embodiment, although illustration to use the parameter suitable with air quantity be target charging efficiency Ec _TGTCome computing coefficient of thermal efficiency K _Pi, but also can replace target charging efficiency Ec _TGTAnd with air quantity (quality, volume) in the cylinder or volumetric efficiency etc., also can replace coefficient of thermal efficiency K _PiAnd with the thermal efficiency or the parameter relevant with it.In addition, in the above-described embodiment, although illustration for computing coefficient of thermal efficiency K _PiAnd with target charging efficiency Ec _TGTWith actual rotational speed Ne, but also can replace actual rotational speed Ne and with the variance estimation of engine rotary speed at interior prediction engine rotary speed.

Claims (5)

1. the control gear of a motor is characterized in that, has:

The target ignition moment arithmetic element that the target ignition that the air quantity of calculating in the cylinder that should import motor is used carries out computing constantly;

The thermal efficiency arithmetic element of constantly thermal efficiency of described motor being carried out computing according to described target ignition; And

According to the target empty tolerance arithmetic element of the described thermal efficiency to carrying out computing as the target empty tolerance that should import the desired value of the air quantity in the described cylinder,

Described target ignition is the described target empty tolerance that calculates according in the past execution cycle in described target empty tolerance arithmetic element of arithmetic element and the time interim described target ignition of current execution cycle is carried out computing constantly constantly.

2. the control gear of motor as claimed in claim 1, it is characterized in that, the target air-fuel ratio arithmetic element that has according to the described target empty tolerance that calculates at the execution cycle in described past and the time interim target air-fuel ratio of current execution cycle is carried out computing

Described thermal efficiency arithmetic element is revised the thermal efficiency of described motor according to described target air-fuel ratio.

3. the control gear of motor as claimed in claim 1 or 2, it is characterized in that, has the target exhaust reflux ratio arithmetic element of the time interim target exhaust reflux ratio of current execution cycle being carried out computing according to the described target empty tolerance that calculates at the execution cycle in described past

Described thermal efficiency arithmetic element is revised the thermal efficiency of described motor according to described target exhaust reflux ratio.

4. the control gear of motor as claimed in claim 1, it is characterized in that the described target empty tolerance that the execution cycle of described target ignition moment arithmetic element basis before just calculates is carried out computing constantly to the described target ignition of current execution cycle.

5. the control gear of motor as claimed in claim 1, it is characterized in that, has the implementation time of ignition arithmetic element that the implementation time of ignition corresponding to the moment of being lighted a fire by spark plug according to the amount of actual air for combustion pair and the reality that are imported in the cylinder of described motor carries out computing

Described target ignition constantly arithmetic element is independent of the described target ignition that the ground-to-air tolerance computing of described implementation time of ignition uses and constantly carries out computing.

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