• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    The invention relates to a method and a device for operating an internal combustion engine with at least two cylinders which can be driven with fuel stored in a tank of varying fuel quality and / or stored fuel mixtures from a first and at least one second fuel in different mixing ratios and different fuel grades and / or different fuel mixtures. composition requires different air / fuel conditions to achieve a stable combustion and / or has different evaporation behaviors. According to the invention, it is provided that in a post-start phase of the internal combustion engine a cylindrical individual variation of the fuel quantity is supplied to at least one first cylinder which is supplied to a leaner or to a fatter air / fuel mixture and at least a second cylinder a corresponding variation is made to a fatter or leaner air. / / fuel mixture and in connection therewith a difference of the running unevenness at both cylinders is evaluated, whereby the variation of the variation on the difference of the running unevenness of both cylinders is evaluated and a fuel adaptation is carried out therefrom for all cylinders or that the fuel composition is determined. The device according to the invention has an internal combustion evaluation unit with the internal combustion engine with which a cylinder-individual variation of the amount of fuel supplied to the cylinders can be preceded by a leaner or fatter air / fuel mixture and a difference in the unevenness of the cylinders involved in miscible variation. With the method and the device for carrying out the method, an optimal mixture can be provided in the post-start phase, whereby a reliable and robust evaluation of the walking smoothness is applied. (Figure)
    公开号:SE1050278A1
    申请号:SE1050278
    申请日:2010-03-24
    公开日:2010-10-02
    发明作者:Laurent Nack
    申请人:Bosch Gmbh Robert；
    IPC主号:
    专利说明:

    15 20 25 30 2 The arbitrary mixture of petrol and alcohol results in a wide range of variations of the fuel properties, especially of the stoichiometry and the evaporation properties.
    DE 4117440 C2 discloses a method for adaptive setting of a fuel / air-fuel mixture for taking into account fuel properties during operation of an internal combustion engine which has a lambda control which produces a control factor RF and which has an adaptation integrator which produces an adaptation factor AF. with variable adaptation speed, which in addition to the control factor RF affects the setting of the fuel / air mixture.
    In this case, it is ensured that it is checked whether the lambda control deviation amplitude exceeds a first threshold value and if so, the adaptation rate is set at an increased value until a predetermined condition is met, after which feedback is returned to a low adaptation rate.
    The method makes it possible to drive combustion engines that can be operated with different fuels without disturbance. For example, in the case of a change of a petrol fuel to a fuel mixture of 85% ethanol and 15% petrol, the injection time must be extended by more than 20%, in order to obtain the same lambda value in the exhaust gas. According to the method described in the document DE 4117440 C2, a corresponding adaptation procedure is performed in addition.
    Since in the case of a fuel change, in comparison with the equalization of the aging effect or the manufacturing effect, a strong correction of the injection times must be made and thus of the adaptation intervention in the proposed process the adaptation speed is significantly increased at an identified fuel change.
    Based on the set adaptation value, the fuel-mixing ratio can be determined. Despite the increased adaptation rate, the process requires a sufficiently long turn-in time. If a strong change in the fuel-mixing ratio is caused by a refueling process, this can lead to starting difficulties and to the ignition failing ("coughing"), which leads to increased exhaust emissions.
    In addition to a change in the fuel-mixing ratio of an internal combustion engine operated in Flex-Fuel operation, a variation in the fuel quality, for example even in pure petrol operation, can also lead to starting problems. In this case, fuel quality is especially included in the fuel's evaporation properties. If the alcohol content is unknown, a distinction between the two causes is difficult. Greasing of the air / fuel mixture in response to poor starting behavior of the internal combustion engine is therefore not always suitable for Flex-Fuel use, as is known from pure petrol operation. 1 from another application from the applicant with file number DE 10 2007 035317 a method is known for operating an internal combustion engine with at least two cylinders which can be propelled with fuel stored in a tank of varying fuel quality and / or stored fuel mixtures from a first and at least one second fuel in different mixing ratios and wherein different fuel grades and / or fuel mixtures require different air / fuel ratios to achieve a stable combustion and / or exhibit a varying evaporation behavior. It is ensured that, in the case of at least one cylinder, a cylinder-individual variation of the fuel mixture supplied to the cylinder is carried out against a leaner and / or against a fatter air / fuel mixture, that the variation of the variation on the starting properties and / or the smoothness of the cylinder and / or internal combustion engine is evaluated and that in the event of an achieved improvement of the starting properties and / or smoothness, a fuel adaptation is carried out for all cylinders.
    The process enables rapid identification and avoidance of starting problems in the event of a change in fuel quality or fuel composition with an effect on the flammability of the fuel mixture.
    When using the procedure, however, it turns out that in practice problems can arise in an evaluation of the smoothness, which can lead to an incorrect interpretation of the smoothness values. On the one hand, therefore, very stable boundary conditions are required with respect to, for example, speed, load and / or temperature, which in practice cannot always be guaranteed. On the other hand, spreads, which can be traced back to manufacturing tolerances and / or aging of components, can distort the evaluation.
    It is therefore the task of the invention to provide a method for providing an optimal air / fuel mixture especially for the post-start phase of an internal combustion engine in which a reliable evaluation of the smoothness is guaranteed.
    It is further the task of the invention to provide an anorexia for carrying out the procedure. Description of the invention The object concerning the process is solved according to the invention by in a post-start phase of the internal combustion engine a cylinder-individual variation of the fuel mixture fed to the cylinder against a leaner or against a fatter air / fuel mixture is carried out at at least a first cylinder. a second cylinder performs a corresponding variation against a fatter or a leaner air / fuel mixture and in connection therewith a difference of the gait uniformity of the two cylinders is evaluated, the input of the variation of the difference of the gait uniformity of the two cylinders being evaluated and a fuel adaptation being performed therefrom for all cylinders or that the fuel composition is determined therefrom.
    The task of the device is solved by the internal combustion engine having a control / evaluation unit, with which a cylinder individual variation of the amount of fuel supplied to the cylinders can be given (controlled) against a leaner or against a fatter air / fuel mixture and a difference in the smoothness of the cylinders involved. in the mixture variation can be evaluated.
    With the method according to the invention and the device for carrying out the method, especially in the post-start phase, an optimal air / fuel mixture can be stated, before a reliable feedback from the lambda probe is available in this phase, whereby it can be reliably and accurately identified if the mixture is too lean. or too fat. This applies to petrol-powered internal combustion engines as well as to Flex-Fuel applications, as described earlier. In accordance with the invention, it is then assumed that differences in smoothness values or smoothness values between at least two different cylinders are used and not absolute smoothness values. Thus, the above-mentioned disadvantages regarding unstable boundary conditions resp. spreads are largely eliminated. An additional advantage results from the fact that when evaluating the difference in the smoothness or smoothness of only two cylinders, a clearer and above all earlier feedback to the mixture can be derived than would be possible in an evaluation of the total smoothness. In a preferred method variant, it is provided that the cylinder-individual variation of the air / fuel mixture of the first cylinder and of the second cylinder is carried out at a constant target lambda value taken together for both cylinders. The target lambda value can then be time-dependent, depending on the load and operating phase.
    The variation of the air / fuel mixture of the first cylinder and the second cylinder can then be carried out continuously or also periodically, typically a variation of up to about 10% is disturbed against the average value of the air / fuel mixture of the first cylinder and the second cylinder. . In addition, the variation of the air-to-fuel mixture can also be switched between the two cylinders, whereby the hitherto grease-driven cylinder becomes a lean-driven cylinder and the hitherto lean-driven cylinder becomes a fat-driven cylinder. This has the advantage that cylinder individual differences (different adjustment) can be filtered out.
    In a further method variant, it can be provided that the cylinder-individual variation of the air / fuel mixture of the first cylinder is carried out symmetrically with the cylinder-individual variation of the air / fuel mixture of the second cylinder. On the one hand, this offers the advantage that through the variation the lambda value remains constant for the total internal combustion engine. On the other hand, the variation of the air / fuel mixture can easily be given technically by means of a character change for the two partial cylinders. In an alternative method variant, while maintaining the principle for evaluating the difference of the running smoothness, it can be provided that the cylinder-individual variation of the air / fuel mixture of the first cylinder is carried out by means of a cylinder-individual variation of the air / fuel mixture of several other cylinders of the internal combustion engine. , whereby for all participating cylinders taken together a constant target lambda value is set.
    It is also conceivable that the cylinder-individual variation of the air-1 fuel mixture is carried out at your cylinder pairs, whereby for all participating cylinder pairs taken together a constant target lambda value is set. Here, too, the maintenance of the evaluation principle with respect to the difference in walking smoothness is ensured for the participating cylinder pairs. In carrying out the method variant, it has proved advantageous when the value k = 1 is set as the target lambda value. This is derived from the course of the walking smoothness depending on the lambda value. The curve is similar to a "bathtub" and has a pronounced rise at a value from k = 1. The walking unevenness increases rapidly for a value k> 1. ideally, therefore, the cylinders are driven around a value k = 1, a cylinder being driven at a value k> 1 and the second partial cylinder at k <1, which is very easy to realize and also relatively insensitive with respect to magnitudes of the smoothness.
    The evaluation procedure further ensures that the walking evenness difference is compared with a predetermined threshold value resp. with a setpoint for the gait evenness difference and depending on the result of the comparison, the total mixture is made leaner or fatter, with which a simple and robust adjustment of the mixture preparation can be realized. In addition, a corresponding control circuit, for example in the form of a P1 control, is provided which is correspondingly realized technically in the device or realized with a corresponding software.
    It may be provided that a value for the smoothness of the fat-driven cylinder / cylinders is subtracted from the value of the gait of the lean cylinder / cylinders and is compared with the threshold value and if this threshold value is exceeded the total mixture is made fatter and below the threshold value, the total mixture is made leaner. This evaluation can be realized in a short time within the control / evaluation unit without large consumption of hardware and / or software. It is used here that a forecast of the current lambda value is possible due to the course of the gait uniformity in dependence on the lambda value and the previously determined difference for the gait uniformity of the cylinders and correspondingly a mixing operation can be performed. If the threshold value is not exceeded and the ignored threshold value is not exceeded, it can be assumed that the current lambda value is close to the target lambda value, usually k = 1.
    The functionality of the method with the previously described method variants can be implemented in the control / evaluation unit or in a superior engine control device of the internal combustion engine as hardware and / or software. A software implementation 10 15 20 25 30 7 has the advantage that the parameters can be changed quickly through a software update if new knowledge is available.
    A preferred use of the process as previously described provides for the adaptation of operating parameters of an internal combustion engine to the composition of a gasoline / ethanol fuel mixture and / or a gasoline / methanol fuel mixture and / or gasoline / ethanol / methanol fuel mixture and / or a diesel biodiesel. -fuel mixture. Especially in Flex-Fuel applications, this method can be used to determine the ethanol content of the petrol. The method can also be used advantageously for the plausibility (plausibility assessment) of an ethanol sensor. The method can also be used in a system without a sensor, which takes place, for example, in an ethanol content determination with the aid of a start-up / hot-running adaptation. It is used here that the walking smoothness, especially in the post-start phase, depends very strongly on the ethanol content resp. the methanol content of the fuel mixture due to the specific evaporation properties. This makes it possible, among other things, to distinguish ethanol content errors from the usual multiplicative fuel errors.
    An equally preferred use of the method provides for the adaptation of operating parameters of the internal combustion engine to a present gasoline grade.
    The invention is explained in more detail in the following with the aid of an exemplary embodiment illustrated in the figures. It shows: Fig. 1 in schematic illustration a fl fate diagram of the procedure and Fig. 2 in schematic illustration a diagram of the walking smoothness depending on a lambda value or an ethanol content.
    Fig. 1 shows a fate diagram 1 for the method according to the invention. After a start 10 of the procedure, it is next checked in a reading 20 for the connection conditions, if all connection conditions are met. These can be, for example, fixed waiting times between periodically carried out mixing interventions or operating parameters, with which a conclusion can be drawn about a disturbance-free operation of the internal combustion engine. If the reading conditions are not met, a repetition takes place until all conditions are met. It may also be ensured that the procedure is stopped further. 10 15 20 25 30 8 If all conditions are met, in a function block thinning / degreasing 30 takes place a targeted thinning of the air / fuel mixture for a first cylinder of the internal combustion engine. A second cylinder is offered in the assumed example a greased air-fuel mixture, whereby thinning and greasing of the air / fuel mixture for the two cylinders of the internal combustion engine are to be carried out symmetrically in the assumed process example. Preferably, a value of 1 = 1 is maintained over all cylinders.
    The connection is determined in a uniformity evaluation block 40 by a difference of the uniformity between the two cylinders participating in the process. In this case, the difference of the walking smoothness is formed by subtracting a value for the walking smoothness of a cylinder which is operated with a lean air / fuel mixture from a value for the walking smoothness of a cylinder which is operated with a pre-greased air / fuel mixture. The walking smoothness difference (AL) thus formed is first compared in a reading block 50 with a threshold value (S). If the threshold value (S) is exceeded, which is checked with a reading 51, the total mixture is greased (mixture greasing 60). If the ignored threshold value (-S) is exceeded, which is checked with a reading 52, the total mixture is emaciated (emaciated) (mixture emaciation 70). If the threshold value (S) at reading 51 is not exceeded and the negated threshold value (-S) is not exceeded at reading 52, it can be assumed that a lambda value 112 is in the vicinity of k = 1. In this case there is no total mixture fattening or total mixture emaciation, whereby a regression takes place at the beginning of the procedure and the steps after reading are repeated or the procedure is stopped, for example if a time lapse has been determined.
    In a further reading 80, it may be arranged that with the aid of this reading it is checked whether a period end has been reached. This reading is especially necessary in a periodic use of the method. If this is not the case, the difference of the smoothness is further determined in the smoothness evaluation block 40 and corresponding to the comparison with the threshold value (reading block 50), the total mixture is greased or emaciated (mixture greasing 60 or mixing slimming 70). If the end of the period has been reached, a further reading 90 takes place to check whether the final condition has been reached. This may, for example, be the case when the lambda control is active in the after-start phase of the internal combustion engine resp. fully delivers reliable values from the lambda probe. If this is the case, the procedure is stopped (end 100). In case this is not the case, the system performs a renewed passage of the process step starting with reading 20. In Fig. 2, a diagram 110 is illustrated for the course of a value for the walking smoothness 111 in dependence on a lambda value 112. The "bathtub-like" curve course has a strong rise at a k = 1. At small lambda values 112, significantly below h = 1, the walking unevenness 111 also increases very strongly. Ideally, the differential smoothness 116 is relatively low at a target lambda value 113 (here k = 1), since the smoothness of the cylindrically driven cylinder 111 and the corresponding grease driven cylinder 118 deviates only slightly in this curve section. A total lambda value 119 for the two cylinders involved in the mixing variation corresponds to the target lambda value 113 (rake = 1).
    If a large difference uniformity is detected in the case of too lean mixture 114, an engagement of grease mixture 120 takes place. If a large difference in uniformity is detected in the case of too fat mixture 115, an intervention of thin emaciation 113 takes place.
    In a Flex-Fuel application, for example, it may also be provided that the walking smoothness 111 is evaluated depending on an ethanol content 140 instead of the Iambda value 112.
    With the method and the device for carrying out the method, an optimal mixture can be set in the post-start phase, whereby a reliable and robust evaluation of the gait smoothness is applied.
    权利要求:
    Claims (12)
    [1]
    Method for operating an internal combustion engine with at least two cylinders that can be operated with fuel stored in a tank of varying fuel quality and / or stored fuel mixtures from a first and at least a second fuel in different mixing ratios and wherein different fuel grades and / or fuel mixtures of different composition requires different air / fuel conditions to achieve a stable combustion and / or exhibits a varying evaporation behavior, characterized in that in a post-start phase of the internal combustion engine a cylinder-individual variation of the amount of fuel supplied to the cylinder is carried out at at least one first cylinder. a leaner or against a fatter air / fuel mixture and in the case of at least a second cylinder a corresponding variation is carried out against a fatter or leaner air / fuel mixture and in connection therewith a difference of the gait uniformity of both cylinders is evaluated, the variation på surface on the difference of walking smoothness unit of both cylinders is evaluated and from this a fuel adaptation is carried out for all cylinders or the fuel composition is determined.
    [2]
    Method according to Claim 1, characterized in that the cylinder-individual variation of the air / fuel mixture of the first cylinder and the second cylinder is carried out at a constant target lambda value (113) taken together for both cylinders.
    [3]
    Method according to Claim 1 or 2, characterized in that the cylinder-individual variation of the air / fuel mixture of the first cylinder is carried out symmetrically with the cylinder-individual variation of the air / fuel mixture of the second cylinder.
    [4]
    Method according to claim 1 or 2, characterized in that the cylinder-individual variation of the air / fuel mixture of the first cylinder is carried out by means of a cylinder-individual variation of the air / fuel mixture of fl your second cylinders of the internal combustion engine, wherein for all participating cylinders taken together, a constant target lambda value (113) is set. 10 15 20 25 30 11
    [5]
    Method according to Claim 1 or 2, characterized in that the cylinder-individual variation of the air / fuel mixture is carried out at cylinder your cylinder pairs, a constant target lambda value (113) being set for all participating cylinder pairs taken together.
    [6]
    Method according to one of Claims 1 to 5, characterized in that the value k = 1 is set as the target lambda value (13).
    [7]
    Method according to one of Claims 1 to 6, characterized in that the difference in gait unevenness is compared with a predetermined threshold value and that, depending on the result of the comparison, the total mixture is made leaner or fatter.
    [8]
    Method according to Claim 7, characterized in that a value for the smoothness of grease-driven cylinders / of the grease-driven cylinders is subtracted from the value of the walking smoothness of a lean-driven cylinder / of the lean-driven cylinders and is compared with the threshold value and if this threshold value is exceeded, the total mixture is made fatter and if the negated threshold value is exceeded, the total mixture is made leaner.
    [9]
    Use of the method according to any one of claims 1-8 for adapting operating parameters of an internal combustion engine to the composition of a petrol / ethanol-fuel mixture and / or a petrol / methanol-fuel mixture and / or petrol / ethanol / methanol-fuel mixture and / or a diesel / biodiesel fuel blend.
    [10]
    Use of the method according to any one of claims 1-8 for adapting operating parameters of the internal combustion engine to a present petrol quality.
    [11]
    Device for operating an internal combustion engine with at least two cylinders which can be driven by fuel stored in a tank of varying fuel quality and / or stored fuel mixtures from a first and at least a second fuel in different mixing ratios and wherein different fuel qualities and / or fuel mixtures of different composition require different air / fuel conditions to achieve a stable combustion and / or exhibit a varying evaporation behavior, characterized in that the internal combustion engine has a control / evaluation unit with which a cylinder individual variation of the amount of fuel supplied the cylinders can be set against a leaner or against a fatter air-fuel mixture and a difference in the smoothness of the cylinders involved in the mixture variation can be evaluated.
    [12]
    Device according to claim 11, characterized in that the functionality of the method according to claims 1-8 is implemented in the control / evaluation unit or in a superior engine control device of the internal combustion engine.
    类似技术:
    公开号 | 公开日 | 专利标题
    DE102014119377A1|2015-07-09|Methods and systems for fuel ethanol determination by an oxygen sensor
    JP4617876B2|2011-01-26|Fuel injection control device for in-cylinder internal combustion engine
    DE102012208092B4|2022-02-24|Method and control unit for compensating for a voltage offset of a two-point lambda probe
    US20090107441A1|2009-04-30|Adaptive fuel control strategy for engine starting
    SE533288C2|2010-08-10|Method and apparatus for determining the composition of a fuel mixture
    JP2004316471A|2004-11-11|Control device for internal combustion engine
    US20100101548A1|2010-04-29|Fuel injection control device and method for multi-fuel engine
    US9863353B2|2018-01-09|Methods and systems for estimating an air-fuel ratio with a variable voltage oxygen sensor
    SE532892C2|2010-05-04|Method of operating an internal combustion engine
    DE112015004509B4|2022-02-10|Control device for an internal combustion engine
    SE1050278A1|2010-10-02|Method and apparatus for operating an internal combustion engine
    DE102006017568B4|2008-01-31|Calibrate a model-based fuel control with fuel dynamics compensation for engine startup and start-to-run transition
    DE102005010028B4|2007-04-26|Regulator device for compensation of scattering of injectors
    DE102006017560B4|2009-06-10|Model based fuel allocation for engine start and start-to-run transition
    JP2009243408A|2009-10-22|Fuel injection control apparatus for multi-fuel engine
    DE102012203199A1|2012-09-27|Control of fuel injection based on the volatility of a fuel
    JP2004197591A|2004-07-15|Oil dilution fuel estimation device and control device for internal combustion engine with this estimation device
    CN108060985A|2018-05-22|For the method and system based on the water operating of contacts exhaust gas oxygen sensor at sensor
    DE102015220263B4|2019-07-11|CONTROL DEVICE
    US9388755B2|2016-07-12|Method for operating an internal combustion engine having a plurality of cylinders in homogeneous operation
    DE102015108459A1|2015-12-10|Methods and systems for fuel ethanol content determination via an oxygen sensor
    US20160032884A1|2016-02-04|Fuel property determination apparatus for internal combustion engine
    SE532891C2|2010-05-04|Method for determining the composition of a fuel mixture
    JP4010149B2|2007-11-21|Fuel property determination device
    JPH0629588B2|1994-04-20|Air-fuel ratio controller for internal combustion engine
    同族专利:
    公开号 | 公开日
    SE535076C2|2012-04-03|
    BRPI1000966A2|2012-01-24|
    DE102009002096A1|2010-10-07|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    JP3259967B2|1990-06-01|2002-02-25|ローベルトボツシユゲゼルシヤフトミツトベシユレンクテルハフツング|How to adaptively adjust the fuel-air mixture|
    DE102007035317A1|2007-07-27|2009-01-29|Robert Bosch Gmbh|Method for operating an internal combustion engine|DE102013218903A1|2013-09-20|2015-03-26|Robert Bosch Gmbh|Method and device for lambda and ignition angle control|
    DE102014210849A1|2014-06-06|2015-12-17|Robert Bosch Gmbh|Method and device for reducing a running noise in an internal combustion engine|
    SE542396C2|2018-05-07|2020-04-21|Husqvarna Ab|Improved fuel control|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    DE200910002096|DE102009002096A1|2009-04-01|2009-04-01|Internal-combustion engine e.g. petrol-driven internal-combustion engine, operating method, involves evaluating influence of variation in difference of irregular variations of cylinders, and determining fuel composition|
    [返回顶部]