阅读说明：本技术 具有减小的回流量的燃料喷射 (Fuel injection with reduced regurgitant volume ) 是由 A·西门子 于 2018-03-13 设计创作，主要内容包括：本发明涉及一种用于运行内燃机(2)的喷射系统(1)的方法(100),其中,所述喷射系统(1)包括用于一种或多种燃料(3)的高压存储器(11)并且高压存储器(11)中的额定压力p<Sub>S</Sub>根据至少一个特性曲线族(16)遵循所述内燃机(2)的负载要求L,其中,为了降低所述高压存储器(11)中的实际压力p,来自所述高压存储器(11)的过量燃料(3,31)被减压(99),其中,至少在所述负载要求L暂时下降到具有更低负载的运行点(29)上时,所述高压存储器(11)中的额定压力p<Sub>S</Sub>相对于根据特性曲线族(16)对该运行点(29)设置的值p<Sub>K</Sub>被提高(110,110a-110c)。本发明还涉及一种对应的计算机程序产品。(The present invention relates to a kind of for running the method (100) of the spraying system (1) of internal combustion engine (2), wherein, the spraying system (1) includes the high pressure accumulator (11) for one or more fuel (3) and the rated pressure p in high pressure accumulator (11) S The load requirement L of the internal combustion engine (2) is followed according at least one characterisitic family (16), wherein, in order to reduce the actual pressure p in the high pressure accumulator (11), excess of fuel (3 from the high pressure accumulator (11), 31) (99) are depressurized, wherein, rated pressure p at least when the load requirement L is temporarily dropped on the operating point (29) with more low-load, in the high pressure accumulator (11) S The value p that the operating point (29) is arranged with respect to characterisitic family (16) K It is enhanced (110,110a-110c).The invention further relates to a kind of corresponding computer program products.)

1. the method (100) of spraying system (1) of the one kind for running internal combustion engine (2), wherein the spraying system (1) includes For the rated pressure p in the high pressure accumulator (11) and the high pressure accumulator (11) of one or more fuel (3)_SAccording to At least one characterisitic family (16) follows the load requirement L of the internal combustion engine (2), wherein in order to reduce the high pressure storage Actual pressure p in device (11), the excess of fuel (3,31) from the high pressure accumulator (11) are depressurized (99), and feature exists In, at least when the load requirement L is temporarily dropped on the operating point (29) with more low-load, the high pressure accumulator (11) the rated pressure p in_SWith respect to characterisitic family (16) for value p set by the operating point (29)_KIt is enhanced (110,110a-110c)。

2. the method according to claim 1, wherein the rated pressure p_SAt least it is maintained at predetermined base The horizontal p of plinth_BUpper (111), the foundation level are higher than value set by the idle running according to characterisitic family for the internal combustion engine p_K。

3. method according to claim 1 or 2 (100), which is characterized in that the rated pressure p_SMaximum and/or minimum Time rate of change dp_SThe maximum and/or minimum time change rate dp/dt of/dt and/or the actual pressure p are in load requirement L Ratio is more strongly limited (112) when load requirement L is increased when decline.

(100) 4. according to the method in any one of claims 1 to 3, which is characterized in that the decoupling of the internal combustion engine (2) (26a) is evaluated the temporary decline that (113) are the load requirement L.

5. according to the method for claim 4 (100), which is characterized in that cause to shift gears by automatic transmission (27) The requirement (27a) of journey is evaluated the temporary decline that (114) are the load requirement L.

6. the method according to any one of claim 4 to 5 (100), which is characterized in that make the rated pressure p_SRelatively In the value p according to set by characterisitic family (16)_KThe degree and car speed v and/or manual transmission of modification or automatic change The shelves (27b) of fast device (27) being finally placed in are related (110b).

7. method (100) according to any one of claim 1 to 6, which is characterized in that when the magnitude of load requirement decline Change rate dL/dt when being more than predetermined threshold value Δ L, it is temporary that the decline of the load requirement L, which is evaluated (115),.

8. method (100) according to any one of claim 1 to 7, which is characterized in that the decline of the load requirement L It is temporary for being evaluated (116) first, also, when the load requirement L is maintained at threshold value Δ L for predetermined time interval When following, when specified the amount of injection q is more than predetermined threshold value q_SWhen, and/or when driver wishes that f has lower bear corresponding to described When operating point (29) of load, the decline is just be evaluated as nonvolatile.

9. method (100) according to any one of claim 1 to 8, which is characterized in that make rated pressure p_SRelative to root According to value p set by characterisitic family (16)_KThe degree of modification and the state variable x of storage container (13)₁And pass through fuel (31) the state variable x of decompression or the fuel feed system part influenced by the decline of actual pressure p₂, with wait subtract The state variable x of the fuel (31) of pressure₃And/or with ambient environmental conditions x₄Related (110c).

10. method according to any one of claim 1 to 9, which is characterized in that liquefied natural gas (LNG) is used as firing Material.

11. a kind of computer program product, the computer program product includes machine readable instruction, when described machine readable Instruction when being executed by computer and/or controller, which promotes the computer and/or the controller to implement according to power Benefit require any one of 1 to 10 described in method.

Technical field

The present invention relates to a kind of methods for running fuel injection system, in the method by fuel with transformable Pressure is maintained in high pressure accumulator.

Background technique

In the high pressure co-rail system for internal combustion engine, fuel, such as diesel fuel or liquefied natural gas (LNG) are by height Press pump is compressed to high-pressure horizontal and is maintained in high pressure accumulator (rail).The high pressure accumulator is typically supplied multiple injections Device, these injectors inject fuel into the combustion chamber of each cylinder of internal combustion engine.This spraying system for example by US 6, Known to 024,064 A.

The amount of injection q needed for each spraying cycle depends on the load requirement L of internal combustion engine.If load requirement L declines, Need less fuel.When load requirement L declines strongly, fuel quantity cannot only be reduced by shortening injection duration, but The pressure p in high pressure accumulator must additionally be reduced.Separately therefrom, for the combustion characteristics of same fuel quantity also with pressure P is related, and fuel is supplied to injector by the pressure.

When there is the demand for reducing the pressure p in high pressure accumulator, excessive fuel is introduced back into from high pressure accumulator In storage container (case).In the fuel being introduced back, have been used to for fuel being compressed to the energy of high pressure level with heat Form be stored.In addition, the temperature of compressed fuel by with the fuel be located next to ambient enviroment (such as rail body, pipeline, Engine room) heat exchange be determined jointly.

Although the heat can be for example utilized according to 1 319 821 Bl of EP, so as in the case where external temperature is low Preheating diesel fuel and the blocking for preventing fuel filter, but under most of operation conditions, the heating of fuel reserve but has There is detrimental effect.Therefore, 6 US, it is related to fuel temperature that 647,968 Bl disclose consumption efficiency, and proposes by mentioning High flow capacity and the temperature for reducing the fuel being introduced back.In addition, being usually initially used for compressed fuel and being converted into heat when leading back The energy of amount is consequently not used for the driving of vehicle, that is to say, that actual loss.

Summary of the invention

A kind of method for running the spraying system of internal combustion engine has been generated within the scope of the present invention.The injection system System includes the high pressure accumulator for one or more fuel.Rated pressure p in high pressure accumulator_SAccording at least one characteristic Family of curves follows the load requirement L of internal combustion engine.In order to reduce the actual pressure p in high pressure accumulator, in high pressure accumulator Excess of fuel be depressurized.

Fuel can be for example introduced back into storage container, wherein can be between high pressure accumulator and storage container Optionally setting intermediate receptacle is as buffer, for consuming dress to fuel temperature adjustment or also as additional before being fed back into The inspection position set.It is deposited however, at least part amount of fuel also can be for example depressurized in pre- delivery pump and supply high pressure Intermediate pressure level between the high-pressure pump of reservoir.Then, at least part energy for having been used for compressed fuel is further It is utilized.The amount of injection q needed for characterisitic family for example can give each spraying cycle to each load requirement L.With for The boundary condition for spraying duration can relatively determine or at least limit required rated pressure p_S.The smallest injection duration is by most Small pulse duration limits, and can manipulate injector by the pulse duration.Maximum injection duration passes through according to internal-combustion engine rotational speed Following manner is defined: the injection must carry out in the partial region determined according to angle that crankshaft rotates.

In addition, the same characteristic curve race or another characterisitic family can also be by required rated pressure p_SDirectly Ground or also in relation in other Coupled Variable to load requirement L.

Characterisitic family especially can in fuel consumption as few as possible or also in as few as possible hazardous emission or It is optimised in terms of noise emission.It the use of this characterisitic family is for realizing for consumption in the case where multiple internal combustion engines Key as defined in characteristic and the standard of environmental characteristics.

According to the present invention, at least when load requirement L is temporarily dropped on the operating point with more low-load, high pressure storage Rated pressure p in device_SWith respect to characterisitic family for value p set by the operating point_KIt is enhanced.

In the case where load requirement L temporarily declines, decline is especially appreciated that as, the decline with maximum probability immediately completely or portion Ground is divided to be compensated by the raising of load requirement L.

Rated pressure p_SRaising have the effect that be obviously reduced in the of short duration decline of load requirement L or even completely Interrupts fuel backs into storage container from high pressure accumulator.Thus the heat input in storage container is obviously reduced.This is two Aspect causes apparent energy saving, on the one hand, has been put to the energy in fuel compression less with cannot be further The form of heat loss being utilized.On the other hand, less energy is consumed, for this undesirable heat is cold by fuel But device is exported from fuel storage device.

Reduced heat input into storage container especially has when using liquefied natural gas (LNG) as fuel other Remarkable advantage.Natural gas is only liquid when temperature is far below ambient temperature.Therefore, the heat input into storage container It can result in evaporation and boiling point offset.Thus over-voltage and result in storage container may occur there is gas to be determined by safety Surely it is discharged into ambient enviroment.There may be detonable atmospheres in closed space such as parking building for this.In addition, The main component of unburned natural gas is to compare CO₂Obviously more lead to the methane of greenhouse effects.It provides, is used for due to this reason The storage container of LNG at least so insulate well, makes it possible to reach the predetermined retention time between traveling twice And it is discharged without gas.Caused by the additional heat input of reduction that leads back of fuel, can be insulated with the low degree of LNG storage container It realizes the regulation, and/or can realize the longer retention time between traveling twice.

Therefore, obtaining the cost that illustrated advantage is paid is: by rated pressure p_SWith respect to characteristic curve The value p that race was originally arranged the operating point with more low-load_KRaising with it is identified optimal in characterisitic family Value deviates in terms of injection.This may cause: accuracy of spray is deteriorated in the operating point, so that fuel consumption efficiency and nocuousness Object discharge and noise emission may instantaneously be deteriorated.

However it is known that the temporary variation is unessential when considering the whole service of internal combustion engine.It therefore, is described The cost that advantage is paid is smaller compared with cost at first sight.

Thus, for example having of short duration (transition) operation phase of the load requirement L sharply declined to merely comprise internal combustion engine operation The very small accounting of time.Therefore, what is consumed and discharge is temporarily increased energy and combustion caused by by leading back due to reduction Material is saved finally by overcompensation.

If dally it is foreseeable that and then of short duration raising occurs for load requirement L decline-noise level particularly with Be for the short time interval it is unessential, the idle running-noise level is enhanced due to deviation characteristic family of curves.In addition, from Begin to the rate of descent of the actual pressure p technically limited in high pressure accumulator eventually, so that in load requirement L to rated pressure p_SBe enhanced again before, actual pressure p will not may drop to the rated pressure p drastically reduced completely_SOn.Possibly, internal combustion engine Consumption characteristics and emission performance with more low-load operating point in it is even completely non-critical because vehicle is in the fortune It is closed in coast and due to sliding without spraying fuel on row point.

It is known that it is nonsensical when load requirement L only temporarily declines for these reasons, make rated pressure Ps The decline is fully complied with according to characterisitic family and declines the actual pressure p in high pressure accumulator sharply.

It is the shift process of vehicle operation for the load requirement L example temporarily declined.Each such shift process is wanted It asks, is interrupted about 0.5-1 seconds from the transmitting of the power of internal combustion engine.When especially upshifing during accelerator, then this has the negative of reduction It carries and requires the brief period of L that will carry out immediately the stage for requiring L with more high load.Its mode is: pressing down during shift process Rated pressure p processed_SReduction, therefore not only save energy and also slightly improve accelerating performance.

The statement of advantageous effects of the invention before is not limited to the following contents: only when identifying or will load It is required that when the temporary decline of L, just by rated pressure p_SRelative to the predetermined value p by characterisitic family_KIt improves.With physical presence Load requirement L temporarily decline the measure independently for good and all or according to operating point taken generally speaking also can be realized it is described Bright advantage.It is unique and be only dependent upon and lead back the advantages of realized relative to since what is run in vehicle puts down by reduce fuel The balance that the equal time above and caused by characterisitic family deviation more consumes and more discharges, i.e. for example accumulative exhaust gas value.

In addition, advantageous effects of the invention are not limited to the following contents in principle: which kind of specific fuel is used for internal combustion engine Operation.It is depressurized on which position in fuel system with the fuel from high pressure accumulator in principle and which is related to Independently, additional heat is input into fuel system as a whole kind fuel.This is learnt by law of conservation of energy. Fuel type is only much to the heat input and how many heat input can be allowed to have an impact in vehicle operation.Therefore, this hair It is bright to can also use in the single internal combustion engine for example run with diesel fuel or liquefied natural gas (LNG), it can such as select Selecting property in one of described fuel operation double base (double fuel) internal combustion engine in as.Particular advantage ensure that in double base internal combustion Use in machine, and the double base with diesel fuel or LNG is specially being retrofitted to from the single operation with diesel fuel herein In the case where operation.Herein, the advantages of being run with LNG only has following cost: LNG is to the change due to caused by the fuel led back Heat is especially sensitive.The cost is obviously reduced through the invention.

In the particularly advantageous configuration of the present invention, rated pressure p_SAt least it is maintained at predetermined foundation level p_BOn, the foundation level be higher than according to characterisitic family for idling of IC engine set by value p_K.As long as load requirement L is such as This is high, so that according to the corresponding rated pressure p of characterisitic family_KGreater than p_B, then the measure does not have an impact actually.Only Reduce when the such degree of load requirement L, so that p_KDrop to p_BIt, just can practical deviation characteristic family of curves when following.Therefore, In Properly select foundation level p_BIn the case where, even if not monitoring further completely, if there is or will occur load requirement L Temporary decline when, generally speaking also may be implemented significantly to improve.

In another particularly advantageous configuration of the invention, rated pressure p_SMaximum and/or minimum time change rate dp_S/ The maximum and/or minimum time change rate dp/dt of dt and/or actual pressure p is in load requirement L decline when ratio in load requirement L It is more strongly limited when raising.It also especially is understood as such situation to this: limiting time change in load requirement L decline Rate, but such limitation is not provided with when load requirement L is increased.

For example, the inflow adjuster for improving the pressure p in high pressure accumulator, and/or returning for reducing the pressure p Throttle regulator is designed such that, so that giving the time rate of change dp/dt of the predetermined pressure p of the adjuster as regulated variable. The adjuster does not so open valve accurately in inner part, so that there is predetermined time rate of change dp/dt.It therefore can To limit time rate of change dp/dt, mode is: limitation adjusting that is relevant to the time rate of change, being conveyed to adjuster Variable.

As long as the decline of load requirement L continues, rated pressure p_SFinally drop to value p_K, the value is pre- by characterisitic family It is given, for the operating point with more low-load.However, this is occurred with such time delay, it is only temporary in load requirement L When (transition) declines, hence it is evident that reduce or even interrupt rated pressure p_SDecline.On the contrary, when load requirement L is increased, limitation Speed is less advantageous, rated pressure p_SAs the speed increases.Such limitation will make internal combustion engine have worse dynamic Response.

When the operating point of internal combustion engine, especially load requirement L herein, pressure when changing in time, in high pressure accumulator The rated value p of power optimized according to characterisitic family_KAlso with time change.From the volume according to characterisitic family and time correlation Definite value p_K(t) setting out, it is final specified for example to be formed by temporal decaying, smooth, filtering and/or asymptotic weighting Pressure p_S.Rated pressure p_SIt can also be calculated from substitution value-characterisitic family.Such as it is also possible to p_K(t) curve Trailing edge edge lingeringly reaches rated pressure p by delay link_S。

In another particularly advantageous configuration of the invention, the decoupling of internal combustion engine be evaluated as load requirement L it is temporary under Drop.Decoupling just substantially be by controlled clutch pedal or automatically to realize unrelated transition condition.

In another particularly advantageous configuration of the invention, the requirement by shift process caused by automatic transmission is commented Valence is the temporary decline of load requirement L.Here, term " automatic transmission " includes any such speed changer, in the speed change In device, automate to the such degree of shift process, so that the clutch pedal in vehicle is extra, i.e., it not only include full-automatic Speed changer and manual transmission including automation.Compared with engine controller, gearbox controller especially can be preparatory Shift process will occur for notice.Engine controller has then been learnt in advance: being transmitted below with the power of load requirement L decline Short interruption will be temporary.Correspondingly, rated pressure p_SIt is otherwise due decline be weakened or interrupt, i.e., it is specified Pressure p_SThe value p predetermined by characterisitic family can be raised to_KMore than.

In another particularly advantageous configuration of the invention, when the change rate dL/dt of the magnitude of load requirement decline is more than When predetermined threshold value △ L, the decline of load requirement L is be evaluated as temporary.In general, condition of road surface and driver wish f Being related to speed will not suddenly change.On the contrary, decoupling when power transmitting interrupt suddenly switched as far as possible, so as to from Clutch is only in rubbing for time accounting as few as possible and therefore wears in strong state.

In another particularly advantageous configuration of the invention, the decline of load requirement L is be evaluated as temporary first.When negative When load requires L to be maintained at threshold value Ls or less for predetermined time interval, when specified the amount of injection q is lower than predetermined threshold value q_S When, and/or when driver wishes that f corresponds to the operating point with more low-load, the decline is just be evaluated as nonvolatile. The design contained behind is, in typical traveling, the temporary suppression ratio driver of load requirement L wishes the change of f obviously more Continually exist.That is, being in maximum probability very much when there is the decline of load requirement L, which is temporary.In individual cases In show: the decline may be lasting.As explained herein before, but especially in terms of emission performance internal combustion is depended on The characteristic accumulated on the time of machine.In the summation, by reducing leading back the advantages of fuel of heating is realized and overcoming has The shortcomings that a small number of stages of low-load, in these stages, accuracy of spray is not optimal.This is particularly suitable for following background, In low-load when ratio in more high load, per unit time or every section of distance consumes significantly less fuel, so that low negative It is at least partly opposite when load to generate more discharges.

In general, the temporary decline in order to identify load requirement L, it may be considered that such as driver wishes f (corresponding to throttle Pedal position state), by vehicle speed changer intervention after load requirement L and/or from direct operating point log history The analysis assessment of statistical data and logic association.

In addition it is also possible to consider the characteristic parameter of current point of operation, such as revolving speed of internal combustion engine and car speed v.

Rated pressure p can advantageously be made_SThe value p being arranged with respect to characterisitic family_KThe degree of change and heating Fuel leads back the influence correlation that interference how will be currently generated to fuel system.For this purpose, the degree for example can be with storage container State variable x₁(such as filling position, pressure and/or temperature) and the decline institute shadow for depressurizing by fuel or passing through actual pressure p The state variable x of loud fuel feed system part₂And the state variable x of fuel to be depressurized₃(such as gas temperature and/or energy Amount) and/or with ambient environmental conditions x₄(such as ambient temperature) is related.

The degree for example can be in pressure offset, under the maximum pressure in drop rate and/or in time constant filter It embodies.The variable or another variable can be coupled to initial nominal pressure p for example with calculation_SIt is upper, on load requirement L, On to required the amount of injection q, in the information of gas pedal, speed changer or clutch, on car speed v, or also couple Onto the change rate and/or derivative of these signals, the variable be for by pressure value p proposed by characterisitic family_K The quantitative measurement deviated from.Change rate limits, i.e. to rated pressure p_SMaximum and/or minimum rate of change dp/dt limitation, right The maximum of actual pressure p and/or the limitation of minimum rate of change dp/dt, and/or to controlling value related to this or control signal The limitation of maximum rate of change for example can be used as characterisitic family relevant to specified the amount of injection q and be stored in controller.It is logical Cross the adjustable one side of the relevance by keep longerly modification rated pressure p_SMake the fuel quantity led back minimize and On the other hand the compromise by faster pressure reduction close between operating normally.The temporal control of the measure, such as Time constant filter about time upper step is also possible to significant.

Such as can continuous (no step) open and stopping gets involved in rated pressure p_SOr the time to the rated pressure In curve.For this purpose, the intervention can for example be calculated by slope (Rampen) time control or relevant to operating point (fade in/out (Fade-In/Out), cross fade (Crossfade), the filter constant of step, progressive line function/hyperbola Function).

The method can be especially performed on engine controller.For that purpose it is necessary to advantageously neither change controller The affiliated sensing device or actuating device of internal combustion engine itself is not changed yet.The method can especially be controlled for engine The pure software of device embodies in updating, the product that the software upgrading can independently be sold also for Market for refitting in this regard.Cause This, the present invention also relates to a kind of computer program products with machine readable instructions, when described instruction is by computer and/or control When device processed executes, computer and/or controller is promoted to implement method according to the present invention.

Detailed description of the invention

The alternatively improved present invention is set forth together with the explanation of the preferred embodiment of the present invention below according to attached drawing Measure.

Attached drawing is shown:

Illustrative implementation of Fig. 1 method 100 on the spraying system 1 of internal combustion engine 2；

Pressure p, specified the amount of injection q and car speed v of the Fig. 2 in illustrative accelerator, in high pressure accumulator 11 Time graph.

Specific embodiment

According to Fig. 1, spraying system 1 includes high pressure accumulator 11, which is held by high-pressure pump 12 from storage Device 13 is for giving fuel 3.It is for the sake of clarity not shown as pre- delivery pump needed for the multiple high-pressure pumps 12 of operation.It is adjusted by flowing into It saves device 14 and the pressure p of the fuel 3 in high pressure accumulator 11 is increased to rated pressure p_S.If rated pressure ps declines, fire The margin 31 of material 3 is depressurized from 11 overflow of high pressure accumulator and in the step 99 of method 100 via back flow regular 15, Its mode is: the fuel is introduced back into storage container 13.

Fuel 3 is supplied to injector 17 from high pressure accumulator 11 and is ejected into the vapour of internal combustion engine 2 by the injector 17 In cylinder 22.The burning of fuel 3 within the cylinder 22 drives piston 21, which connect simultaneously via connecting rod 23 and crank 24 with crankshaft 25 And it is in crankshaft 25 in rotary motion.Crankshaft 25 is connect via clutch 26 with automatic transmission 27.It is generated by internal combustion engine 2 Torque m resists mechanical load requirement L and drives vehicle.

Because the demand to fuel 3 is related to load requirement L, characterisitic family 16 is that each load requirement L is directed to The value p as pressure to be placed offer one in high pressure accumulator 11_K: in the value, the burning of fuel 3 is most efficient Ground carry out and in the value discharge of nuisance and noise it is minimum.When load requirement L drops to the fortune with low-load When on row point 29 or such decline will occur, by described value p in the step 110 of method 100_KIt is revised as rated pressure p_S, which is finally transferred to spraying system 1.

In box 110a, guarantee in sub-step 111, rated pressure p_SPredetermined foundation level p is not dropped to_BWith Under.Pressure rate of descent is limited in sub-step 112.On the one hand, rated pressure p is limited_SRate of descent dp_S/ dt, this volume of influencing Constant-pressure p_SModification.On the other hand, the rate of descent dp/dt of actual pressure p is limited, this is by being applied directly to back flow regular It is realized on 15.

In sub-step 113, the decline that decoupling 26a is be evaluated as load requirement L has the signal of temporary characteristic.In son In step 114, the gear shift of automatic transmission 27 requires 27a to be also be evaluated as such signal.In sub-step 115, work as load It is required that the decline of load requirement L is be evaluated as temporarily when the magnitude variations rate dL/dt of decline is more than predetermined threshold value Δ L 's.In sub-step 116, by the time graph L (t) of load requirement compared with threshold value Ls, pass through specified the amount of injection q and threshold Value q_SComparison and the analysis by wishing driver f determine when necessary: be initially be evaluated as temporary load requirement L Decline is not temporary, lasting.

When being determined in sub-step 113 to 116, there is no when the temporary decline of load requirement L, then 111 He of sub-step 112 couples of rated pressure p_SAnd the influence to actual pressure p is neutralized, i.e., modified rated pressure variation is disabled.

As long as rated pressure p_SRelative to the value p as proposed by characterisitic family 16_KIt is modified, then the intensity of the modification exists It is accurately adjusted in box 110b and 110c.In box 110b, the degree of modification and car speed v and with speed changer 27 The shelves 27b being finally placed into is related.The state variable x of storage container 13 is also additionally considered in box 110c₁, fuel supply The state variable x for leading back influenced part by fuel 31 of system₂, fuel 31 to be led back state variable x₃And week Enclose the state variable x of environmental condition₄。

Fig. 2 shows car speed v, required specified the amount of injection q and high pressure accumulator 11 according to illustrative traveling In curve of the pressure p about time t, the specified the amount of injection is the measurement for load requirement L.The traveling is divided into One boost phase I, quiescent phase II and the second boost phase III.It, will be by characterisitic family in order to compare about pressure p Rated pressure p proposed by 16_KAnd modified rated pressure p_STwo example p_S,1And p_S,2It is plotted to identical curve graph In.

First boost phase I is briefly interrupted by two shifts stage a and b.Because herein to the transmitting of the power of speed changer 27 It must briefly be interrupted, so load requirement drops to zero to specified the amount of injection q respectively.Correspondingly, according to spy The suggestion p of linearity curve race 16_KRated pressure will substantially be reduced to idler revolutions p_LL.According to two example p_S,1And p_S,2, modification Rated pressure p afterwards_SIt is considerably higher respectively.Example p_S,1It is main to be arranged to rated pressure p_SChange rate dp_SThe limit of/dt, and Example p_S,2The rate of descent dp/dt of major limitation actual pressure p.

Any unexpected decline of load requirement L is be evaluated as temporary decline first.This is also applied in boost phase I Two interior shifts stage a and b.

However, the decline of load requirement L is for a long time, because vehicle is now with nearly constant in quiescent phase II Speed planar travel.Therefore, it before then needing slightly larger the amount of injection q again, is wanted in coast first Seek the amount of injection q close to zero.When in time point t₁After the variation of modified rated pressure is activated first, modified volume Constant-pressure changes in time point t₂After Δ t terminates in predetermined time interval the case where load requirement L is not increased again It is lower and disabled.

Example p is also shown in quiescent phase II_S,1And p_S,2Between another difference, in example p_S,1In, rated pressure p_S Additionally at least it is maintained at pressure of foundation p_BOn, i.e. idling pressure p_LLActually it is increased to horizontal p_BOn.

Second boost phase III includes another shift stage c, and load requirement L briefly declines simultaneously in the shift stage And correspondingly, modified rated pressure is just activated again.