EP2501917A1

EP2501917A1 - Method and device for controlling a rate control valve

Info

Publication number: EP2501917A1
Application number: EP10773030A
Authority: EP
Inventors: Rainer Wilms; Matthias Schumacher; Joerg Kuempel; Matthias Maess
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2009-11-17
Filing date: 2010-10-21
Publication date: 2012-09-26
Anticipated expiration: 2030-10-21
Also published as: EP2501917B1; US20120283883A1; WO2011061038A1; DE102009046783A1; KR101731135B1; CN102686859A; US9026337B2; KR20120102636A; CN102686859B; IN2012DN02190A

Abstract

The invention relates to a method for controlling a rate control valve (30), at least two characteristic variables (102, 104) characterizing said rate control valve, wherein a control signal supplied to the rate control valve is defined by at least two parameters and, based on the result of a first and a second adaption (90, 92) or based on the result of a first adaption (90) and a first characteristic variable (102), an additional characteristic variable (104) is determined.

Description

Description title

Method and device for controlling a quantity control valve Prior art

The invention relates to a method for operating a quantity control valve. The invention further relates to a computer program, an electrical storage medium, and a control and regulating device. The invention is particularly applicable in a fuel injection system of a

Internal combustion engine, wherein the fuel injection system comprises a high-pressure pump. This high-pressure pump is associated, for example, a quantity control valve for supplying fuel, wherein it controls the amount of fuel delivered by the high-pressure pump. The quantity control valve is provided for example with a magnetically actuated by a coil solenoid valve.

From DE 10 2007 035 316 is a method for driving a

Quantity control valve with a magnetically actuated by a solenoid solenoid valve, in which the coil of the solenoid valve is energized with a first current value to this for supplying fuel to

Close high-pressure pump, wherein the first current value value is lowered when closing the solenoid valve in such a manner to a second current value that an emission of audible sound, which arises during the closing of the solenoid valve during operation of the internal combustion engine is at least partially reduced.

From the non-prepublished DE 10 2008 054 513 a method for controlling a volume control valve influenced by an electromagnetic actuator is known. A drive signal supplied to the electromagnetic actuator is provided by at least two Parameter defined, wherein in an adaptation method, at least a first parameter of this Ansteuersignais is changed at a fixed second parameter of a start value successively to a final value, in which closing or opening of the quantity control valve is at least indirectly not or only just detected, then the first parameter is determined on the basis of the final value at least provisionally and the provisionally fixed first parameter on the basis of at least one current operating variable of the fuel injection system or the second

Is adjusted based on at least one current operating amount of the fuel injection system and the provisionally set first parameter.

These known from the prior art adaptation method vary the parameters of the drive signal of the quantity control valve such that the closing behavior of the quantity control valve is selected in a corresponding manner. A characterization of the behavior of the quantity control valve does not take place.

From the unpublished DE 10 2008 054 512 is actuated for driving one of an electromagnetic actuator

Mengensteuerventils suggested that at least one parameter of a braking pulse of an efficiency of the electromagnetic

Actuating device and / or from a supply voltage of a

Voltage source and / or of a temperature, in particular one

Component of the fuel injection system or the internal combustion engine depends. To characterize the efficiency of the electromagnetic

Actuation device is proceeded as follows: In an adaptation method, an energy supplied to the electromagnetic actuator is successively changed from a starting value to such a final value, in which a closing or opening of the quantity control valve is no longer or only just detected. The final value or a quantity based thereon is used to characterize the efficiency of the electromagnetic actuator. For a particularly accurate adaptation of the control of the quantity control valve to the specimen properties, an exact characterization of the specimen properties is required. Often two or more parameters are necessary for this characterization. However, with only one measurement as known in the art, two characteristics can not be determined independently.

DISCLOSURE OF THE INVENTION The invention relates to a method for controlling a quantity control valve, wherein at least two parameters characterize the quantity control valve, wherein a control signal supplied to the quantity control valve is defined by at least two parameters. The inventive method allows in particular the independent determination of two the behavior of the

Quantity control valve characterizing parameters.

It is particularly advantageous for reducing the emission audible sound when closing the quantity control valve, the control of the

Adjust quantity control valve in a suitable manner to the specimen properties of the quantity control valve. The inventive method for

Control of a characterized by at least two parameters

Quantity control valve, wherein a the quantity control valve supplied

Drive signal is defined by at least two parameters, which is characterized

that based on the result of a first adaptation and a second

Adaptation at least one parameter is determined, or that based on the result of a first adaptation and a first parameter, a second parameter is determined, allows the determination of the specimen properties. The properties of the quantity control valve vary from item to item

Copy.

Is at least a first parameter on a first in the adaptation

Constant value maintained, and at least a second parameter changed from a first start value to such a final value, in which a closing or opening of the quantity control valve just no longer or just just determined is the final value allows the determination of the characterizing relationship between the drive signal and closing / opening behavior of the

Quantity control valve. Characterized in that in a second adaptation, at least a third parameter is maintained at a second constant value, and at least a fourth parameter is changed from a second start value to such a final value, in which closing or opening of the quantity control valve just no longer or straight is first determined, it is possible in conjunction with the final value of the first adaptation, the characterizing relationship between

Determine drive signal and closing / opening behavior of the quantity control valve exactly. The inventive method is inexpensive too

realize, since no additional unit costs arise.

If in this first and second adaptation the first parameter corresponds to the third parameter and the second parameter corresponds to the fourth parameter, the result is an embodiment in which the same parameter is adapted in both adaptations. This embodiment is particularly easy to implement on a control unit. In this embodiment, if at least the first constant value and the second constant value or the first start value and the second start value are unequal, the two results are independent, which allows the characteristic relationship between

To describe drive signal and closing / opening behavior of the quantity control valve by two parameters.

If in this first and second adaptation the first parameter corresponds to the fourth parameter of the second parameter corresponds to the third parameter, the result is an embodiment in which different adaptions occur

Parameters are adapted. This embodiment in conjunction with that at least the first constant value and the second start value or the first start value and the second constant value are unequal allows the characteristic relationship between the drive signal and the closing / opening behavior of the

Quantity control valve to describe by two parameters. These

Embodiment allows the particularly robust determination of the two characteristics describing the characteristic relationship. It is particularly easy to carry out the method according to the invention for pulse-width-modulated drive signals if one of the parameters belongs to the group given by duty cycle during a hold phase or an equivalent size and duration of a pull-in pulse or an equivalent variable.

Carrying out the method according to the invention for electromagnetically controlled quantity control valves is particularly simple if at least one of the parameters belongs to the group given by the efficiency of the quantity control valve or of an equivalent size and ohmic total resistance deviation or of an equivalent size.

If the parameter is determined by a measurement or by an estimate or read from the control unit, it can be in

Connection with the result of a first adaptation, the characteristic relationship between the drive signal and closing / opening behavior of the quantity control valve are described by two parameters. This is particularly efficient because only one adaptation is necessary to determine the two parameters. If an ohmic resistance of a supply line is used as the parameter, this allows, in particular, the particularly simple determination of the ohmic total resistance deviation.

The preceding methods can be used in such a way that, starting from the characterizing variables, the parameters of the triggering signal of the quantity control valve are changed in such a way that an emission of audible sound produced when the solenoid valve is closed is at least partially reduced. The implementation of the preceding methods is advantageously carried out with a computer program programmed for use in a method according to one of the preceding descriptions.

The inventive method thus allows a particularly good adaptation of the control of the quantity control valve to the specimen properties. One The advantage is the reduction of audible sound when closing the

Quantity control valve during operation of the internal combustion engine arises. A further advantage is that the holding current level can be adapted to the exemplary behavior of the valve and the total ohmic resistance effective for the drive signal. For example, the holding current level can be minimized, dissipating less power dissipation and unnecessarily high

Temperature development in the quantity control valve is avoided. Another advantage is that the closing times when tightening the quantity control valve can be better pre-steered, since there is knowledge about the significant uncertain parameters, which for example, the delivery accuracy can be improved.

Another advantage is in controls of energized open electromagnetically controllable quantity control valves, in which the acoustic behavior during opening by a force applied by the electromagnetic control brake pulse, which slows down the movement of the armature, is improved. Here, the braking pulse can be adapted in a particularly suitable manner to the specimen properties of the quantity control valve, which improves the robustness of the desired behavior in borderline pattern cases.

Hereinafter, embodiments of the invention will be explained in more detail with reference to the accompanying drawings. In the drawing show:

Figure 1 is a schematic representation of a fuel injection system of a

Internal combustion engine with a high-pressure pump and a quantity control valve; Figure 2 shows three diagrams in which schematically a drive voltage of a

Magnet coil, a current supply to a solenoid and a stroke of a valve element of the quantity control valve of Figure 1 are plotted over time; FIG. 3 shows a schematic flowchart of an embodiment of the invention

inventive method;

FIG. 4 is a schematic flow diagram of another embodiment than in FIG

FIG. 3 shows the method according to the invention;

Figure 5 is a schematic representation of the ratio of the two

Adaptations and the varied and constant value parameter, in case the same parameter is varied in both adaptations;

FIG. 6 analogous to FIG. 5, with a different constellation of the varied parameters held at a constant value, in the event that the same parameter is not varied in both adaptations.

In FIG. 1, a fuel injection system bears the overall reference numeral 10. It comprises an electric fuel pump 12 with which fuel is conveyed from a fuel tank 14 to a high-pressure pump 16. The

High pressure pump 16 compresses the fuel to a very high pressure and promotes it further into a fuel rail 18. To this several injectors 20 are connected, which inject the fuel in them associated combustion chambers. The pressure in the fuel rail 18 is detected by a pressure sensor 22.

The high-pressure pump 16 is, for example, a

Piston pump with a delivery piston 24, of a not shown

Camshaft in a reciprocating motion (double arrow 26) can be offset. The delivery piston 24 defines a delivery chamber 28, which via a

Quantity control valve 30 can be connected to the outlet of the electric fuel pump 12. Via an outlet valve 32, the delivery chamber 28 can also be connected to the fuel rail 18.

The quantity control valve 30 comprises an electromagnetic

Actuator 34 which operates in the energized state against the force of a spring 36. When de-energized, the quantity control valve 30 is open, in the energized state it has the function of a normal inlet valve. Check valve. The electromagnetic actuator 34 may be designed in particular as a magnetic coil. This is referred to below as "coil".

The electromagnetic actuator 34 is driven by a control and regulating device 54, which is connected to it via a current-carrying line 56.

It is inventively recognized that for suitable control of the quantity control valve at least two the quantity control valve

characterizing parameters are important. These characteristics are

For example, an efficiency of the quantity control valve and a resistive total resistance deviation.

The efficiency of the mass control valve 30 is defined as the ratio of the (quasi-static) attraction force on the armature that is being required for tightening to the actual quasistatic current in the coil at that moment. If the factor is normalized so that nominal valves have an efficiency of 1, for example, efficient patterns (fast tightening) have efficiency> 1, inefficient patterns (slow tightening) efficiency <1. Efficiency is determined, for example, by tolerances in the design of the magnetic circuit as well as the other dynamic parameters. Another residual air gap, for example, leads u.a. to a decrease in efficiency, since at constant current less magnetic flux is built, resulting in less attractive force. A high spring force also leads to a decrease in the tightening force, and thus to an efficiency <1.

The ohmic total resistance consists of several serial

Partial resistors together (e.g., from: coil of the quantity control valve, lines, contact resistance, power amplifier). Each of these resistors, however, is subject to uncertainties of resistance, which with a controlled pilot control of the quantity control valve 30 certain

Deviations occur. Examples of such uncertainties result, for example, from errors in the temperature model of the coil, or from

Uncertainties in the contact resistance in the contacts. From the Difference of the total ohmic resistance to a nominal total ohmic resistance results in the ohmic total resistance deviation.

In Figure 2, the course of a drive voltage U is plotted against time in the upper diagram 2a, which at the electromagnetic

Actuator 34 is applied. You realize that this

Drive voltage U is clocked in the embodiment in terms of pulse width modulation. The middle diagram 2b of Figure 2 shows the corresponding coil current I. In the lower diagram 2c of Figure 2, the corresponding stroke H of the quantity control valve 30 is shown.

2 that the voltage signal U and the coil current I resulting therefrom initially have a so-called "starting pulse" 56. During this starting pulse, the coil is driven with a constant voltage Correspondingly, there is a rapid increase in the coil current designated by the reference numeral 60 in Figure 2. The pull-in pulse 56 is followed by a holding phase 58, in which the coil is driven with a pulsed voltage 64. The effective drive voltage U is determined by the duty cycle The resulting coil current 60 shows a timing corresponding to the voltage signal and, depending on the effective drive voltage, an increase, a largely constant behavior (as illustrated in the exemplary embodiment in FIG.

It can also be seen from FIG. 2 at the stroke H of the quantity control valve 30 that the quantity control valve is initially in its opened state, then due to the coil current resulting from the tightening pulse

Movement sets and closes at a time t ₂ and goes to attack, resulting in a strike noise.

After the end of the hold phase 58 of the voltage drive of the coil, the coil current 60 drops to zero. The stroke 62 of the quantity control valve changes such that the valve transitions from its closed state to its open state. It is inventively recognized that a signal for controlling the

Quantity control valve 30 is advantageously defined by at least two parameters. In the case of a pulse width modulated control when closing the quantity control valve 30, these are, for example, the duty cycle during the hold phase 58 and the duration of the tightening pulse 56. In the exemplary embodiment, a pulse-width-modulated control is assumed in the following, their signal through the two parameters

Duty cycle during the holding phase and duration of the tightening pulse is defined.

In the known from the prior art adaptation method, a parameter of the control of the quantity control valve 30 (for example, the duration of the tightening pulse) while maintaining constant the other parameters (eg the duty cycle during the holding phase) is successively varied until it is determined that the quantity control valve just not more or just closing. The resulting value of the successively varied parameter now only allows a detection of an averaged parameter which is the superimposed influence of the characterizing parameters, ie

for example, the efficiency and the ohmic total resistance deviation represents. Essentially two extreme cases can be identified, in which the characterizing parameters influence the properties of the quantity control valve in the same way. These are, for example, first the case of low efficiency and positive ohmic total resistance deviation and secondly the case of high efficiency and negative ohmic

Total resistance deviation.

By contrast, in this example, the three cases are, in particular, low efficiency and negative ohmic total resistance deviation, secondly high efficiency and positive ohmic total resistance deviation, and thirdly nominal efficiency and vanishing ohmic

Total resistance deviation with the known from the prior art adaptation method indistinguishable. The method according to the invention allows the independent determination of the two characterizing parameters, that is, for example, of efficiency and ohmic total resistance deviation.

The method according to the invention is based on the knowledge that a single measured quantity (for example the result of an adaptation) can not be used for the simultaneous reliable estimation of two independent unknown parameters (in the exemplary embodiment the efficiency and resistive total resistance deviation). If, on the other hand, according to the invention, a second adaptation is carried out, which takes place, for example, with a changed basic parameterization, then two parameters (in the exemplary embodiment the efficiency and ohmic total resistance deviation) can be determined from the result of the first adaptation and the result of the second adaptation. As part of the

Embodiment is hereinafter assumed that the two characteristic of the behavior of the quantity control valve 30 characteristics are given by the efficiency and the ohmic total resistance deviation. Alternatively or additionally, other variables can be used as parameters, for example one for efficiency or ohmic

Total resistance deviation equivalent size.

FIG. 3 shows the sequence of the method according to the invention. In a first adaptation 90, a variation of a parameter, e.g. the duration of the tightening pulse 56, the closing behavior of the quantity control valve 30 varies. The result 94 of this first adaptation 90 is the value of the varied one

Parameters in which the quantity control valve 30 just no longer or just closes.

In a second adaptation 92, the variation of a parameter, e.g. the duration of the tightening pulse 56, the closing behavior of the quantity control valve 30 varies. The result 98 of this second adaptation is the value of the varied parameter at which the quantity control valve 30 is no longer or just now closing.

Starting from the result 94 of the first adaptation 90 and the result 98 of the second adaptation 92, by means of a calculation 96, for example a Computation or a map, a first characteristic 102 - eg the efficiency and possibly a second characteristic 104 - eg the ohmic

Total resistance deviation - determined. This first parameter 102 and this possibly second parameter 104 are used in the control and regulating device 54 in order to generate, for example with the aid of a characteristic map, an improved control of the quantity control valve 30, in particular with respect to the acoustic behavior.

In the adaptation 90, for example, the duration of the tightening pulse 56 is varied successively while the duty cycle is kept constant during the holding phase 58, until it is determined that the quantity control valve 30 is no longer or just closing. This is done, for example, by evaluating the measuring signal of the pressure sensor 22. The result 94 in this embodiment is the value of the duration of the tightening pulse at which the quantity control valve 30 is no longer or just now closing.

Similarly, in the adaptation 92, for example, the duty cycle during the holding phase 58 while simultaneously keeping the duration of the tightening pulse 30 is varied successively until it is determined that the quantity control valve just no longer or just closes. The result 98 is in this

Embodiment, the value of the duty cycle, in which the

Flow control valve 30 just stops or is just closing.

An alternative embodiment is shown in FIG. In a first adaptation 90, a variation of a parameter, e.g. the duration of the tightening pulse 56, the closing behavior of the quantity control valve 30 varies. The result 94 of this first adaptation 90 is the value of the varied one

By a default 100, for example by a measurement, a first parameter 102 is provided. Based on the result of the first adaptation 90 and the first parameter 102, a second parameter 104 is determined. This first parameter 102 and this second parameter 104 are used in the control and regulating device 54 in order to generate, for example with the aid of a characteristic map, an improved control of the quantity control valve 30, in particular with regard to the acoustic behavior.

The default 100 can be given, for example, by measuring the ohmic total resistance deviation. This is done according to the invention particularly advantageous by the evaluation of a current value of

Activation signal at a predetermined voltage and given

Duty cycle. The determination of the ohmic total resistance deviation is then particularly simple. In the pulse width modulated control used in the exemplary embodiment, the effective current according to the invention is particularly advantageous over a plurality of phases of the pulse width modulated

Drive signal in the steady state at saturated current, i. at a flat stroke 62. The evaluation over several phases of the

pulse width modulated drive signal allows the most simple

Determination of an RMS current to determine the ohmic

Total resistance deviation. The determination of the steady state current with saturated current and without movement of an armature of the

Quantity control valve makes it possible to exclude feedback effects and thus allows the particularly accurate determination of ohmic

Total resistance deviation.

The efficiency as a second parameter is then determined on the basis of the measurement of the total ohmic resistance deviation and of the result of FIG.

Adaptation determined.

FIG. 5 describes the relationship of the first adaptation 90 and the second adaptation 92 to one another. In the first adaptation method 90, a first parameter 110 - e.g. the duty cycle during the hold phase 58 - held at a first constant value 112 and a second parameter 114 - e.g. the duration of the tightening pulse 56- changed from a first starting value 116 to such a final value, in which closing or opening the

Quantity control valve 30 is not or only just determined. In the second adaptation method 92, a third parameter 118 - eg the duty cycle during the hold phase 58 - is held at a second constant value 120 and a fourth parameter 122 - eg the duration of the pull-in pulse 56 - is changed from a second start value 124 to such a final value. in which a closing or opening of the quantity control valve 30 is no longer or just just determined.

In the embodiment shown in FIG. 5, therefore, e.g. the first parameter 110 and the third parameter 118 both the duty cycle during the hold phase 58 and the second parameter 114 and the fourth

Parameter 122 is both the duration of the pull-in pulse 56. The first parameter 110 thus corresponds to the third parameter 118 and the second parameter 114 to the fourth parameter 122.

Analogous to FIG. 5, another possible embodiment is shown in FIG. For example, in the first adaptation 90, the duty cycle during the hold phase 58 is held at a second constant value 120 and the duration of the pull-in pulse 56 is changed, and in the second adaptation 92 the duration of the pull-in pulse 56 is maintained at a first constant value 110 and the duty cycle during the hold phase changed. Thus, the first parameter 110 and the fourth parameter 122 correspond to both e.g. both the duration of the pull-in pulse 56, and the second parameter 114 and the third parameter 118 both the duty cycle during the hold phase 58. The first parameter 110 thus corresponds to the fourth parameter 122 and the second parameter 114 to the third parameter 118th

For the independence of the first adaptation 90 from the second adaptation 92, it is important that the start parameterization be different from the constant value and the starting value. In the constellation shown in Figure 5, this means that either the first constant value 112 is different from the second constant value 120, or the first start value 116 is different from the second start value 124, or both.

In the constellation shown in FIG. 6, this means that either the first constant value 112 is different from the second start value 124 or the first seed 116 must be different from the second constant 120, or both.

The inventive method for the identification of at least two

Characteristics is advantageously repeated at long intervals. The reason for this is the fact that over time a slow change in the

Characteristics, e.g. efficiency, occurs. This is caused for example by wear. Since this change is slow, it is advantageous to store the determined parameters, for example in the control unit.

If maps are used in the method described, it is advantageous to adapt these maps to the current battery voltage, since the currents in the control of the quantity control valve and possibly the result of an adaptation (in particular, if the adapted parameter is given by the duty cycle) of the Battery voltage can depend.

In the described method, the ohmic

Total resistance deviation provided via a measurement, it is advantageous to repeat this measurement at frequent intervals, since the change of resistance occurs situationally.

Furthermore, it is advantageous to have three or more independent adaptations

perform, since the accuracy of the determined characteristics can be further improved. In this case, if necessary, an algorithm for minimizing a defined deviation is required, which is stored, for example, together with corresponding maps in the control and regulation unit.

Claims

claims

1. A method for controlling a quantity control valve (30), wherein

at least two characteristic variables characterize the quantity control valve (30), wherein a control signal supplied to the quantity control valve is defined by at least two parameters, characterized in that on the basis of the result of a first adaptation (90) and a second adaptation (92) at least one parameter (104) is determined, or that based on the result of a first adaptation (90) and a first characteristic (102), a second characteristic (104) is determined.

2. Method according to claim 1, characterized in that in the first adaptation (90) at least one first parameter (110) is kept at a first constant value (112), and at least one second parameter (114) is maintained from a first start value (116). is changed to such a final value, in which a closing or opening of the quantity control valve (30) is not or only just determined.

3. Method according to claim 2, characterized in that in a second adaptation (92) at least one third parameter (118) is kept at a second constant value (120), and at least one fourth parameter (122) is held from a second starting value (124). is changed to such a final value, in which a closing or opening of the quantity control valve (30) is not or only just determined.

4. The method according to claim 3, characterized in that the first

Parameter (110) corresponds to the third parameter (118) and that the second parameter (114) corresponds to the fourth parameter (122).

5. The method according to claim 3, characterized in that the first

Parameter (110) corresponds to the fourth parameter (122) and that the second parameter (114) corresponds to the third parameter (118).

6. The method of claim 4, characterized in that at least the first constant value (112) and the second constant value (118) or the first start value (116) and second start value (124) are unequal.

The method of claim 5, characterized in that at least the first constant value (112) and the second start value (124) or the first start value (116) and the second constant value (120) are unequal.

8. The method according to any one of claims 2-7, characterized in that at least one of the parameters belongs to the following group:

Duty cycle during a holding phase (58) or a size characterizing this size; Duration of a suit pulse (56) or a variable characterizing that size.

9. The method according to any one of the preceding claims, characterized

characterized in that at least one of the characteristics belongs to the following group: efficiency of the quantity control valve or an equivalent quantity; ohmic total resistance deviation or an equivalent size.

10. The method according to any one of the preceding claims, characterized

in that the parameter is determined by a measurement or by an estimate or read out of the control unit (54).

11. The method according to claim 10, characterized in that a resistance of a supply line (56) is used as a characteristic.

12. The method according to claim 11, characterized in that the determination of the resistance of the supply line (56) via an evaluation of a Current value of the drive signal at a predetermined voltage and a predetermined duty cycle takes place.

13. Computer program, characterized in that it is programmed for use in a method according to one of the preceding claims.

14. An electrical storage medium for a control and / or regulating device (54) of a fuel injection system, characterized in that a computer program for use in a method of claims 1 to 16 is stored on it.

Control and / or regulating device (54) for a fuel injection system, characterized in that it is programmed for use in a method according to one of claims 1 to 16.