Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/20—Output circuits, e.g. for controlling currents in command coils
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/02—Circuit arrangements for generating control signals
  • F02D41/04—Introducing corrections for particular operating conditions
  • F02D41/06—Introducing corrections for particular operating conditions for engine starting or warming up
  • F02D41/062—Introducing corrections for particular operating conditions for engine starting or warming up for starting
  • F02D41/064—Introducing corrections for particular operating conditions for engine starting or warming up for starting at cold start
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
  • H01F7/1805—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current
  • H01F7/1816—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current making use of an energy accumulator
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
  • H01F7/1844—Monitoring or fail-safe circuits
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/20—Output circuits, e.g. for controlling currents in command coils
  • F02D2041/2017—Output circuits, e.g. for controlling currents in command coils using means for creating a boost current or using reference switching
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/20—Output circuits, e.g. for controlling currents in command coils
  • F02D2041/202—Output circuits, e.g. for controlling currents in command coils characterised by the control of the circuit
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D41/00—Electrical control of supply of combustible mixture or its constituents
  • F02D41/20—Output circuits, e.g. for controlling currents in command coils
  • F02D2041/202—Output circuits, e.g. for controlling currents in command coils characterised by the control of the circuit
  • F02D2041/2055—Output circuits, e.g. for controlling currents in command coils characterised by the control of the circuit with means for determining actual opening or closing time
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/021—Engine temperature
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/06—Fuel or fuel supply system parameters
  • F02D2200/0606—Fuel temperature
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
  • F02D—CONTROLLING COMBUSTION ENGINES
  • F02D2200/00—Input parameters for engine control
  • F02D2200/02—Input parameters for engine control the parameters being related to the engine
  • F02D2200/06—Fuel or fuel supply system parameters
  • F02D2200/063—Lift of the valve needle
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
  • H01F7/1805—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current
  • H01F7/1816—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current making use of an energy accumulator
  • H01F2007/1822—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current making use of an energy accumulator using a capacitor to produce a boost voltage
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
  • H01F7/00—Magnets
  • H01F7/06—Electromagnets; Actuators including electromagnets
  • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
  • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
  • H01F7/1844—Monitoring or fail-safe circuits
  • H01F2007/185—Monitoring or fail-safe circuits with armature position measurement

Definitions

• the present invention relates to a method for controlling a solenoid valve of a fuel! Njektors and a computing unit and a computer program for its implementation.
• Injection systems for internal combustion engines convey fuel from the tank to the combustion chamber of the internal combustion engine.
• Fuel injectors feed fuel from a high-pressure accumulator to a combustion chamber of the internal combustion engine.
• Such fuel injectors may have a magnetic valve, in which a magnetic coil is energized in order to lift a magnet armature and thereby release a passage opening for fuel.
• a magnetic valve in which a magnetic coil is energized in order to lift a magnet armature and thereby release a passage opening for fuel.
• the armature stroke is also influenced by the fuel temperature and fuel pressure.
• boost phase injection valves to shorten switching times in a first phase (boost phase) of their control are switched to a boost voltage, so that a particularly high first current in a magnetic coil for once a maximum value is reached.
• the boost phase usually characterizes the beginning of an armature movement, ie an initial acceleration of the armature.
• the boost voltage is generated, for example, from a DC-DC converter from a vehicle battery and can thus be much higher than the battery voltage, so that a correspondingly higher first current flows in the coil. As a result, an armature of the solenoid valve can be accelerated more.
• the boost voltage is buffered in a so-called boost capacitor.
• the coil In an immediately after the first current increase phase of the activation (pull-in phase), the coil is switched to the opposite of the boost voltage smaller battery voltage to carry out a residual armature movement.
• the tightening phase provides the anchor motion approximately until a maximum anchor stroke is reached.
• a third phase (holding phase) follows the suit phase. In this case, the coil is operated with a further and compared to the first two phases smaller current. For controlling in the holding phase but also the battery voltage is used.
• the holding phase ensures that the armature remains approximately at a constant stroke.
• the coil can also be switched during the tightening phase to the opposite of the battery voltage higher boost voltage.
• Such methods are known, for example, from DE 102 42 606 A1 and DE 10 2010 027 989 A1.
• DE 10 2010 000 827 A1 describes a fuel injector with injection nozzles controlled by a nozzle needle and a control chamber which communicates with a high and low pressure side of the fuel injector and which can be reversed by a control valve arrangement between a closing pressure and an opening pressure.
• the control room is associated with a force or pressure sensor that detects characteristic pressure changes during closing and opening.
• This sensor is also referred to as Needle Closing Sensor (NCS sensor).
• NCS sensor Needle Closing Sensor
• NCC Needle Closing Control
• An inventive method is used to control a solenoid valve of a fuel injector for injecting pressurized fuel into an internal combustion engine, with a solenoid and a means of energizing the solenoid to release a flow opening for fuel liftable
• the solenoid valve can be used in particular as a servo or control valve for the fuel! be used.
• the solenoid valve is operable in a first mode and in a second mode, wherein in each of the modes the solenoid for lifting the armature for a first period of time with a starting current, and then for a second period of time with a holding current which is less than the starting current , is energized.
• the first time duration may also include a boost current before the starting current, as mentioned above.
• the solenoid valve is first driven in the first mode, and in response to at least one predetermined criterion is changed from the first to the second mode. In the first operating mode, the first time duration is longer and / or the holding current higher than in the second operating mode.
• Seat throttle limit can be achieved, especially at low temperatures, in which, for example, by increased viscosity of the fuel, the lifting of the armature is slowed down.
• the solenoid valve is initially activated in the first operating mode if, during a start of the internal combustion engine, a further characteristic temperature for the internal combustion engine, for example a cooling water temperature, is below a predetermined temperature threshold value.
• a further characteristic temperature for the internal combustion engine for example a cooling water temperature
• the solenoid valve is initially actuated in the first operating mode if a time duration within which the armature is moved by a predetermined time is reached. th value is raised above a predetermined Hubschwellwert, ie when the solenoid valve opens too slowly. Reasons for this can be, for example, wear or increased friction.
• first period in which the pull-in current is used can now be raised far enough even at lower lifting speed of the magnet armature so that the solenoid valve can be kept open with the subsequent holding current.
• a too short first time duration could lead to the magnet armature not being lifted far enough and thus not reaching the magnet coil sufficiently tightly to be kept open by means of the magnetic force produced by the holding current, which can be significantly lower than during the starting current become. This would undesirably reduce the flow rate of fuel or, for example in the case of a switching valve, would not reach the seat throttle limit, which may result in a very low flow rate.
• the longer first period of time can be further increased by a higher holding current of the armature, since thus a higher magnetic force can be generated in order not to hold the armature, but continue - possibly even slightly - raise.
• the starting current in the first operating mode for example in the range from 14 to 18 A, can be generated by a battery or vehicle electrical system voltage, for example.
• the subsequent holding current for example in the range of 6 to 8 A - or even if it is increased compared to the second mode, for example in the range of 10 to 12 A - can also be generated by the battery or vehicle electrical system voltage. Damage to a control unit that provides the starting current is not to be expected if these current values are adhered to, in particular, for example, a maximum current of approx. 18 A. Values between 450 and 900 s, in particular between 600 and 800 s, are considered as the first time duration in the first operating mode - at least at the beginning.
• a typical time duration in the second operating mode is 450 ⁇ , for example.
• the at least one predetermined criterion comprises reaching or exceeding at least one predetermined operating period of the solenoid valve since the beginning of the first operating mode and / or reaching or exceeding at least one predetermined value of at least one of the
• Internal combustion engine characteristic temperature This can be achieved that the first mode, which requires a higher load of the solenoid valve than the second mode, not unnecessarily long is used. For example, it can be assumed that after a certain period of operation, the internal combustion engine is sufficiently warmed up, so that the mentioned disadvantages no longer occur when the solenoid valve is cold.
• temperatures can be used directly to initiate the change.
• the at least one characteristic temperature may include a temperature of a return of the fuel and / or a fuel tank and / or a cooling water of the internal combustion engine or a combination of at least two of these temperatures. Likewise, a combination of one or more of these temperatures with the operating time is possible.
• the at least one predetermined criterion reaches or exceeds at least one predetermined value of a stroke of the magnet armature and / or reaches or falls below at least one predetermined value of a voltage level of a sensor for detecting a closing of a nozzle needle of the fuel injector (this may be the NCS sensor mentioned at the beginning) in each case during the second time duration.
• the temperature of the internal combustion engine and thus the temperature of the fuel influences the lifting speed of the magnet armature.
• a measure of the temperature of the fuel This hub can therefore be used as a criterion for switching to the second operating mode.
• a measure of the stroke can be determined very easily. It is expedient in this case if reaching or exceeding the at least one predetermined value of the stroke based on a time course of the stroke and / or reaching or falling below at least the predetermined value of the voltage level of the sensor on the basis of the voltage level of the sensor over several second time periods is determined.
• the stroke or the voltage level can be determined. If the stroke now increases over the second time periods and thus the activation processes of the solenoid valve or reduces the voltage level, this means that the temperature has risen. Accordingly, when reaching or exceeding a predetermined value, it is possible to change to the second operating mode. Likewise, it is expedient if the reaching or exceeding of the at least one predetermined value of the stroke and / or the reaching or falling below at least the predetermined value of the voltage level of the sensor respectively by means of test measurements during the first operating mode with reduced holding current and / or reduced first time duration, So tightening current duration, is determined.
• each a drive with respect to the otherwise usual for the first mode holding current and / or the usual starting current or first time a drive operation with reduced holding current and / or or reduced first period of time.
• the stroke of the armature reaches or exceeds a predetermined value or the voltage level reaches or falls below a predetermined value, it can be assumed that the temperature has risen. It is particularly expedient if, as a reduced holding current and / or a reduced first time duration, a holding current and / or such a time duration as in the second operating mode is used. Then you can switch to the second mode as soon as possible.
• switching from the first operating mode to the second operating mode by stepwise reduction of the first time duration and / or of the holding current as a function of the at least one criterion.
• a gradual change between the two operating modes is possible.
• different values of the at least one criterion and / or different criteria may be selected accordingly for this step change for each stage.
• the first time period can be reduced in steps of 50, 100 or 150 s, for example.
• these levels can also vary.
• An arithmetic unit according to the invention e.g. a control device of a motor vehicle is, in particular programmatically, configured to perform a method according to the invention.
• Suitable data carriers for providing the computer program are in particular magnetic, optical and electrical memories, such as e.g. Hard drives, flash memory, EEPROMs, DVDs, etc. It is also possible to download a program via computer networks (Internet, intranet, etc.). Further advantages and embodiments of the invention will become apparent from the description and the accompanying drawings.
• Figure 1 shows schematically a solenoid valve, in which a method according to the invention can be carried out.
• Figure 2 shows a typical course of a current in the solenoid of a solenoid valve and associated courses of the armature stroke at different temperatures.
• Figure 3 shows waveforms of a current in the solenoid of a solenoid valve, associated injection rates, NCS signal waveforms and courses of the armature stroke compared between a non-inventive method and a method according to the invention in a preferred embodiment.
• FIG. 4 shows different first time periods of a starting current as a function of a temperature when using a method according to the invention in a preferred embodiment.
• FIG. 1 schematically shows a solenoid valve 100 in which a method according to the invention can be carried out.
• the solenoid valve 100 has an electromagnet 1 10 with a magnetic coil 1 1 1, which may be formed, for example, annular.
• a voltage U for example by an executing arithmetic unit 180, for example a control device, the current I flows in the magnetic coil 1 1 1.
• a magnet armature 120 is provided with which a flow opening 150 of the solenoid valve 100 can be closed or released.
• the magnet armature 120 in this case has a component 122 which closes the flow opening 150.
• This component 122 is designed, for example, in the form of a bolt with a partially conically tapering end in the direction of the throughflow opening 150.
• the armature 120 further includes an armature wing 121 which is provided at the top, ie in the direction of the magnetic coil 1 1 1 facing end of the armature 120.
• the armature wing 121 may be formed integrally with the component 122 or be mechanically connected to the component 122.
• a spring 130 which acts on the armature 120 and without energizing the magnetic coil 1 1 1 and thus without magnetic force, the armature 120 presses into or against the passage opening 150 and closes it.
• the spring 130 may be in abutment against a suitable component (not shown here) of the solenoid valve 100 on its side facing away from the magnet armature.
• Passage opening 150 is released.
• the armature 120 can be raised to the stop on a arranged on the electromagnet 1 10 adjustment ring 15 1.
• the magnet armature 120 engages with the radially outer end of the armature blade 121.
• FIG. 2 shows schematically a typical course of a current in the magnetic coil of a solenoid valve as well as associated courses of the armature stroke at different temperatures.
• a current I and an armature stroke h are plotted over the time t.
• a starting current can flow in the magnet coil for a first period of time Ati. Subsequently, the current can be lowered to a holding current IH, which then flows for a second period of time At2.
• the course of current shown here is typical of a regular control of the solenoid valve in, for example, operationally warm internal combustion engine.
• three different courses of the armature stroke are now shown schematically in the course of the current shown with increasing viscosity of the fuel flowing through the solenoid valve. While with low viscosity the full armature stroke is achieved in a short time, the full armature stroke is still achieved with slightly higher viscosity, but only after a longer time.
• FIG. 3 shows now curves of a current I in the magnetic coil of a solenoid valve, associated injection rates R, NCS signal curves S and courses of the armature stroke h, in each case over the time t, in comparison between a method not according to the invention (curves h, Ri, Si, hi) and a method according to the invention in a preferred embodiment (curves, R2, S2, h2) during the first mode of operation.
• the NCS signal S stands for the voltage signal of, for example, a piezoelectric sensor, as has already been explained in the introduction. From the course of the NCS signal, the armature stroke h can be derived or determined.
• the starting current is used for a time ⁇ , while in the current h the starting current is used for a period of time Ati which is significantly shorter than the time ⁇ .
• the longer first period of time during which the starting current is used now leads to a larger amount of fuel flowing through the solenoid valve.
• R2 the injection rate
• a second period of time At.2 or At'2 adjoins the first time durations during which the holding current flows in the magnetic coil.
• the second time durations are in each case selected such that the respective first and second time duration result in total a full activation time for the solenoid valve.
• first duration ⁇ t shown here or the associated current profile I2 for the first mode of operation can be used in the context of the method according to the invention
• the shown first duration ⁇ ti or the associated current profile h can be used for the second mode of operation.
• the second operating mode is used when a sufficiently high temperature has been reached, so that too low injection rates due to high viscosity of the fuel occur more.
• FIG. 4 shows various first time durations Ati of a starting current as a function of a temperature T of the fuel when a method according to the invention is used in a preferred embodiment.
• the magnetic coil is actuated in the first operating mode B1 until the temperature T has reached the value Tsi as a criterion.
• the first time period is then gradually reduced from an initial value to the value to be reached in the second mode B2.
• the second operating mode B2 is used when the value Ts2 is reached.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Electromagnetism (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Electrical Control Of Air Or Fuel Supplied To Internal-Combustion Engine (AREA)
• Fuel-Injection Apparatus (AREA)

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Applications Claiming Priority (2)

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Family Applications (1)

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Citations (6)

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• 2016
  • 2016-11-16 DE DE102016222508.1A patent/DE102016222508A1/de active Pending
• 2017
  • 2017-10-24 WO PCT/EP2017/077085 patent/WO2018091232A1/de active Application Filing
  • 2017-10-24 CN CN201780070677.4A patent/CN109952622B/zh active Active
  • 2017-10-24 KR KR1020197016808A patent/KR20190082292A/ko not_active IP Right Cessation

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