WO2015071056A1 - Système d'allumage et procédé de limitation d'un courant de coupure d'un convertisseur élévateur de tension dans un système d'allumage - Google Patents

Système d'allumage et procédé de limitation d'un courant de coupure d'un convertisseur élévateur de tension dans un système d'allumage Download PDF

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Publication number
WO2015071056A1
WO2015071056A1 PCT/EP2014/072541 EP2014072541W WO2015071056A1 WO 2015071056 A1 WO2015071056 A1 WO 2015071056A1 EP 2014072541 W EP2014072541 W EP 2014072541W WO 2015071056 A1 WO2015071056 A1 WO 2015071056A1
Authority
WO
WIPO (PCT)
Prior art keywords
duty cycle
boost converter
operating state
switch
current
Prior art date
Application number
PCT/EP2014/072541
Other languages
German (de)
English (en)
Inventor
Tim Skowronek
Thomas Pawlak
Wolfgang Sinz
Original Assignee
Robert Bosch Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Robert Bosch Gmbh filed Critical Robert Bosch Gmbh
Publication of WO2015071056A1 publication Critical patent/WO2015071056A1/fr

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
    • F02P9/00—Electric spark ignition control, not otherwise provided for
    • F02P9/002—Control of spark intensity, intensifying, lengthening, suppression
    • F02P9/007—Control of spark intensity, intensifying, lengthening, suppression by supplementary electrical discharge in the pre-ionised electrode interspace of the sparking plug, e.g. plasma jet ignition
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/36—Means for starting or stopping converters
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02P—IGNITION, OTHER THAN COMPRESSION IGNITION, FOR INTERNAL-COMBUSTION ENGINES; TESTING OF IGNITION TIMING IN COMPRESSION-IGNITION ENGINES
    • F02P15/00—Electric spark ignition having characteristics not provided for in, or of interest apart from, groups F02P1/00 - F02P13/00 and combined with layout of ignition circuits
    • F02P15/10—Electric spark ignition having characteristics not provided for in, or of interest apart from, groups F02P1/00 - F02P13/00 and combined with layout of ignition circuits having continuous electric sparks

Definitions

  • the present invention relates to an ignition system and a method for limiting a turn-off in a commissioning of a
  • the present invention relates to the protection of electronic components in such an ignition system.
  • Ignition systems are known in the prior art, by means of which a combustible mixture is ignited in spark-ignition internal combustion engines, by electrical energy for a high-voltage breakdown is conducted via an inductive system to a spark gap within the combustion chamber of the internal combustion engine. The spark discharge ignites this within the
  • inductive ignition systems are known in which the transformer essentially combines two functions. On the one hand, a high voltage is provided to the
  • the bypass can be a boost converter comprise or essentially formed by a boost converter.
  • boost converter comprise or essentially formed by a boost converter.
  • Step-up converter is supplied via output-side diodes of the spark gap and the output capacitances. The after the primary side shutdown of the spark gap and the output capacitances.
  • a "duty cycle” is the quotient of duty cycle compared to an entire balancing period of duty cycle and switch-off duration Understood. In other words, the average duty cycle of the
  • Step-up converter adapted to limit the turn-off. Since a step-up converter requires several ON / OFF cycles until the voltage at the output capacitor has reached a steady-state state, until the steady state is reached, depending on the
  • Duty cycle selected so that the material is controlled below the magnetic saturation is adjusted in the course of time during the commissioning of the boost converter according to the invention.
  • the second operating state preferably lies in one substantially
  • the first operating state of a startup of the boost converter is temporally closer than the second operating state.
  • the inventively lower power consumption in the first operating state ensures a stable startup and a limitation of the cut-off current.
  • the first duty cycle and the second duty cycle on the same clock.
  • the switching frequency is not changed when between the first operating state and the second operating state the duty cycle is changed. This allows a simple control with a predetermined clock and cost-effective implementation of the clock.
  • the duty cycle can be kept constant and the
  • the first duty cycle can have a shorter average "on" duration than the second duty cycle, this can be, for example, by a rising edge in the first operating state compared to the second operating state and / or an earlier falling edge of the control signal for the Step-up converter can be realized.
  • a stepless adjustment of the duty cycle allows a particularly accurate metering of the power consumption of the boost converter, which leads to the fastest possible operational readiness with maximum reliability of the boost converter.
  • the clock for controlling the boost converter can, for example, in a frequency range between 20 kHz and 100 kHz, preferably between 40 kHz and
  • the boost converter makes several operating states in succession until the boost converter is transferred from a first operating state to a second operating state.
  • the first operating state in a time range between 0 ⁇ to 50 ⁇ after the
  • Operating state subsequent third operating state for example, from 50 ⁇ to 100 ⁇ after commissioning of the boost converter whir and realize a duty cycle between 50% and 80%, in particular between 65% and 75%.
  • a fourth operating state subsequent to the third operating state can be, for example, from 100 ⁇ to 150 ⁇ after the
  • the second operating state For example, it may connect to the fourth operating state and last from 150 ⁇ to 200 ⁇ after startup. According to the invention it has the highest duty cycle, which is for example between 70% and 100%, in particular between 80% and 90%.
  • the above-mentioned division into four different operating states is to be understood merely as an example and a continuous adjustment of the duty cycle would also be possible.
  • An alternative possibility of determining the duty cycle in a second operating state is to first determine the switch-off current of the boost converter and to determine a suitable second pulse duty factor as a function of the result. The determination may include, for example, measuring the current or receiving a variable which allows conclusions to be drawn about an actual switch-off current. In this way, a situation-appropriate adjustment of the duty cycle can be done without having to resort to stored reference values. In other words, storage space can be saved by a current determination.
  • Assigned predetermined duty cycle which is stored in a memory of the controller.
  • the ignition system for an internal combustion engine configured to perform all steps of the method includes a spark gap for guiding a spark. Further, a boost converter for supplying a spark in the spark gap is provided with electrical energy, which
  • a processing unit is provided, by which the ignition system is arranged to carry out a method as has been described in detail in connection with the first-mentioned aspect of the invention.
  • a memory means may be provided, in which reference values for duty cycles in different operating states are stored.
  • a plurality of limit values for determined switch-off currents can be stored in the memory means, to which respective duty cycles are assigned.
  • the ignition system according to the invention may comprise means for determining a turn-off of the boost converter.
  • measuring means or connections can be present at a signal infrastructure, by means of which the ignition system according to the invention can obtain and use information about a current switch-off current. The obtained
  • information may cause the processing unit to change a first duty cycle to a second duty cycle in response to a predetermined turn-off current.
  • Figure 1 is a circuit diagram of an embodiment of a
  • FIG. 4 shows time diagrams of electrical quantities within the circuit shown in FIG. 3;
  • FIG. 5 is an alternative representation of the electrical quantities within the circuit shown in Figure 3;
  • FIG. 6 shows a detail view of a time diagram of two first
  • FIG. 7 is a timing diagram of an inventively varied
  • Figure 8 is a flow chart illustrating steps of a
  • FIG. 1 shows a circuit of an ignition system 1, which has a
  • Step-up transformer 2 comprising a primary coil 8 and a secondary coil 9 as a high voltage generator whose primary side 3 can be supplied from an electrical energy source 5 via a first switch 30 with electrical energy.
  • a fuse 26 is provided.
  • a capacitance 17 is provided parallel to the input of the circuit or parallel to the electric power source 5.
  • the secondary side 4 of the step-up transformer 2 is powered by an inductive coupling of the primary coil 8 and the secondary coil 9 with electrical energy and has a known from the prior art diode 23 for Einschaltfunkenunterd Wegung, which diode may alternatively be replaced by the diode 21.
  • a spark gap 6 is provided against an electrical ground 14, via which the ignition current i 2 should ignite the combustible gas mixture.
  • a bypass is provided with a boost converter 7 between the electric power source 5 and the secondary side 4 of the step-up transformer 2.
  • the boost converter 7 comprises an inductor 15, a switch 27, a capacitor 10 and a diode 16.
  • the boost converter 7 is the
  • Inductance 15 in the form of a transformer with a primary side 15 1 and a
  • the inductance 15 serves as Energy storage to maintain a current flow. Two first
  • Transformers are each connected to the electric power source 5 and the
  • connection of the secondary side 15_2 of the transformer is connected without a switch directly to a diode 16, which in turn is connected via a node to a terminal of a capacitor 10.
  • This terminal of the capacitor 10 is connected to the secondary coil 9 and another terminal of the capacitor 10 is connected to the electrical ground 14.
  • Step-up converter is fed via the node on the diode 16 in the ignition system and the spark gap 6 is provided.
  • the diode 16 is oriented in the direction of the capacitance 10 conductive. Due to the transmission ratio, a switching operation by the switch 27 acts in
  • Branch of the primary side 15_1 also on the secondary side 15_2. However, since current and voltage according to the gear ratio on one side are higher or lower than on the other side of the transformer, can be found for switching operations more favorable dimensions for the switch 27.
  • the switch 27 is controlled via a drive 24, which is connected via a driver 25 to the switch 27.
  • a shunt 19 as current measuring means or
  • the measuring signal is supplied to the switch 27.
  • the switch 27 is configured to respond to a defined range of the current i 2 through the secondary coil 9.
  • a Zener diode 21 is connected in the reverse direction parallel to the capacitor 10.
  • the control 24 receives a control signal S H ss- About this, the supply of energy via the boost converter 7 in the secondary side and are turned off.
  • the power of the electrical variable introduced by the step-up converter or into the spark gap in particular via the frequency and / or the pulse-pause ratio, can also be controlled via a suitable control signal S H ss.
  • a switching signal 32 is indicated, by means of which the switch 27 can be controlled via the driver 25.
  • the switch 27 When the switch 27 is closed, the inductance 15 is supplied via the electrical energy source 5 with a current, which flows directly into the electrical ground 14 when the switch 27 is closed. With open switch 27, the current is conducted through the inductance 15 via the diode 16 to the capacitor 10.
  • the voltage in response to the current in the capacitor 10 adjusting voltage adds to the voltage across the secondary coil 9 of the step-up transformer 2 voltage, whereby the arc is supported at the spark gap 6.
  • the capacitor 10 discharges, so that 27 energy can be brought into the magnetic field of the inductor 15 by closing the switch to 27 to recharge this energy to the capacitor 10 at a reopening of the switch.
  • the control 31 of the provided in the primary side 3 switch 30 is kept significantly shorter than this by the
  • Switching signal 32 for the switch 27 is the case.
  • the electronic control unit 42 is further connected to a memory 41, from which references in the form of time windows measured from a startup of the boost converter can be read according to duty cycles to be used.
  • the electronic control unit 42 is equipped to supply the control 24 with a control signal S H ss modified as needed in response to which the driver 25 supplies the switch 27 with a changed switching signal 32.
  • the electronic control unit 42 may cause the boost converter in response to receiving the changed switching signal 32 in a first operating state to a reduced power consumption and in a second, following the first operating state operating state, to increased power consumption.
  • the capacity 10 of the ignition system is by means of the inductance 15 of the
  • Switch 27 of the boost converter 7 electrically charged.
  • the switching cycles within the individual operating states each have a predetermined duty ratio TV1, TV2, TV3, TV4, wherein an operating state, for example, corresponds in each case to a predetermined time interval which is in each case related to a switch-on time of the boost converter 7.
  • Operating state or predetermined time intervals is thus assigned in each case a predetermined, stored in a memory duty cycle TV1, TV2, TV3, TV4.
  • the switch 27 of the boost converter 7 is switched on and off once in a switching cycle, wherein energy is stored in the magnetic field of the inductor 15 during a switch-on period of the switch 27 and this stored energy is charged to the capacitor 10 during a switch-off period of the switch 27.
  • the ratio of duty cycle to the sum of duty cycle and stop duration corresponds to
  • FIG. 2 shows time charts for a) the ignition coil current i zs, b) the associated bypass flow through the boost converter i H ss, c) the output-side voltage across the spark gap 6, d) the secondary coil current ⁇ 2 for the illustrated in Figure 1 the ignition system without (501 ) and with (502) using the
  • Switching signal 32 of switch 27 In detail: Diagram a) shows a short and steep rise of the primary coil current i zs , which occurs during the time in which the switch 30 is in the on state ("ON", see FIG.
  • Diagram 3e is located. With turning off the switch 30 also falls
  • Diagram b) also illustrates the current consumption of the boost converter 7, which by a pulse-shaped
  • Control of the switch 27 comes about.
  • clock rates in the range of several tens of kHz have proven to be suitable as switching frequency, in order to realize appropriate voltages on the one hand and acceptable efficiencies on the other hand.
  • Exemplary are the integer multiples of 10000 Hz in Range between 10 and 100 kHz called possible range limits.
  • Diagram c) shows the curve 34 of the voltage at the spark gap 6 during operation according to the invention.
  • Diagram d) shows the characteristics of the secondary coil current i 2 .
  • Secondary coil current i 2 which rapidly drops to 0 without boost converter (501).
  • a substantially constant secondary coil current i 2 (502) is driven via the spark gap 6 by a pulse-shaped control (see diagram f, switching signal 32) of the switch 27, the secondary current i 2 depending on the burning voltage at the spark gap 6 and here For the sake of simplicity, a constant burning voltage is assumed. Only after opening the switch 27 now also the secondary coil current i 2 drops to 0 A. It can be seen from diagram d) that the falling edge is delayed by the use of the boost converter 7.
  • the total time during which the boost converter 7 is used is as t H ss and the time during which energy is in the primary side in the
  • Step-up transformer 2 is indicated as t.
  • Duty cycle of the switch 27 can be variably selected.
  • Step-up converter 7 is processed further. It should be noted that concrete interpretations of many circuit-inherent and external
  • FIG. 3 shows a circuit diagram of a greatly simplified exemplary embodiment of a boost converter 7, which comprises a transformer 15 with a first inductance 15 1 and a second inductance 15_2.
  • the first inductor 15 1 is arranged in a mesh with a switch 27, which by a
  • Switching signal 32 is controlled.
  • switch 27 When switch 27 is closed due to a voltage U a current l H ss- The current l H ss leads to a stored in the magnetic field of the transformer 15 energy which manifests itself during opening of the switch 27 on the secondary side by loading an output-side capacitance 10th A discharge of the capacitance 10 via the secondary-side inductance 15_2 is achieved by a diode 16 between the capacitor 10 and the
  • FIG 4 shows a timing diagram of the switching signal 32 of the switch 27, the boost converter current l H ss and the output side voltage U c on the output side capacitance 10 of the boost converter 7 (see Figure 3).
  • the switching signal 32 is a rectangular signal between 0 V and about 12 V with a
  • a semicolon marking defines the maximum value l max for the boost converter current l H ss, which already exceeds the maximum value l max by approximately 17 A after a first switching cycle I in a second switching cycle II. In a third switching cycle III exceeds the
  • FIG. 5 shows an alternative time diagram of the electrical quantities of
  • the gate voltage U G represents the drive voltage for the switch 27 of the boost converter 7. While in a first
  • FIG. 6 shows a time diagram of the two first switching operations I, II of FIG.
  • Switching signal 32 in a detailed view, from which the influence of an already flowing current l H ss at the beginning of the second switching operation II will be apparent.
  • the current increases after switching independently of the voltage U c on the capacitor according to the charging function of the inductance (voltage,
  • Isolation of the transformer 15 and the functional strength of the switch 27 are considerably at risk.
  • a damaged insulation of the primary-side windings can lead to short circuits.
  • Hotspots within a switch 27 embodied as an IGBT can lead to a permanent conductivity with loss of the switching capability of the switch 27.
  • the area in which the superposition of a current initial value, which correlates with the stored energy of the previous switching cycle, and a new second switching process II is particularly clearly recognizable, is highlighted as a fourth area IV.
  • FIG. 7 shows an adaptation according to the invention of the duty cycle in different operating states of a boost converter 7 according to the invention.
  • a first duty cycle TV1 for the switching signal 32 is selected in a first time range.
  • a third duty cycle TV3 is selected for the switching signal 32, which is greater than the first duty cycle.
  • the third duty cycle TV3 is set to a fourth
  • Duty cycle TV4 increased. Following the fourth operating state, the fourth duty cycle TV4 is increased to a second duty cycle TV2. This has about a 90% "on" duration. In the lower part of the diagram, a primary-side current l H ss can be seen which increases moderately and without impermissible current peaks. Essentially on reaching the second
  • FIG. 8 is a flowchart illustrating steps of FIG
  • step 100 the boost converter of an ignition system is operated with a first duty cycle in a first operating state after its startup.
  • step 200 the boost converter is operated with a second duty cycle in a second operating state. Since the first duty cycle has a lower "on" duration than the second duty cycle, the power consumption of the boost converter is gradually increased, so that no initial
  • the duty cycle TV1, TV2, TV3, TV4 in the step 200 from the first duty cycle TV1 over several switching cycles stepwise until reaching the second
  • the first duty cycle TV1 is thus smaller than the second duty cycle TV2 and also has a shorter average
  • a computer program may be provided which is set up to carry out all described steps of the method according to the invention.
  • the computer program is stored on a storage medium.
  • the method according to the invention can be provided by an electrical circuit provided in the ignition system, an analogous one
  • Circuit, an ASIC or a microcontroller are controlled, which is configured to perform all the steps described in the inventive method.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Ignition Installations For Internal Combustion Engines (AREA)

Abstract

L'invention concerne un système d'allumage et un procédé de limitation d'un courant de coupure (IHSS) lors de la mise en service d'un convertisseur élévateur de tension dans un système d'allumage pour un moteur à combustion interne. Selon l'invention, ledit procédé comporte les étapes suivantes : faire fonctionner (100) le convertisseur élévateur de tension (7) avec un premier rapport cyclique (TV1) dans un premier état de fonctionnement et faire fonctionner (100) le convertisseur élévateur de tension (7) avec un deuxième rapport cyclique (TV2) dans un deuxième état de fonctionnement. Selon l'invention, le premier rapport cyclique (TV1) entraîne, par rapport au deuxième rapport cyclique (TV2), une puissance absorbée moyenne inférieure dans le convertisseur élévateur de tension (7).
PCT/EP2014/072541 2013-11-14 2014-10-21 Système d'allumage et procédé de limitation d'un courant de coupure d'un convertisseur élévateur de tension dans un système d'allumage WO2015071056A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE102013223212 2013-11-14
DE102013223212.8 2013-11-14
DE102014216010.3A DE102014216010A1 (de) 2013-11-14 2014-08-13 Zündsystem und Verfahren zur Beschränkung eines Abschaltstromes eines Hochsetzstellers in einem Zündsystem
DE102014216010.3 2014-08-13

Publications (1)

Publication Number Publication Date
WO2015071056A1 true WO2015071056A1 (fr) 2015-05-21

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PCT/EP2014/072541 WO2015071056A1 (fr) 2013-11-14 2014-10-21 Système d'allumage et procédé de limitation d'un courant de coupure d'un convertisseur élévateur de tension dans un système d'allumage

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WO (1) WO2015071056A1 (fr)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5993968A (ja) * 1982-11-19 1984-05-30 Hitachi Ltd 内燃機関用点火装置
EP0532263A1 (fr) * 1991-09-13 1993-03-17 Motorola, Inc. Convertisseur continu-continu
US20040022078A1 (en) * 2002-02-19 2004-02-05 Fairchild Semiconductor Corporation Soft start techniques for control loops that regulate DC/DC converters
EP2071714A1 (fr) * 2006-10-02 2009-06-17 Panasonic Corporation Convertisseur cc/cc

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5993968A (ja) * 1982-11-19 1984-05-30 Hitachi Ltd 内燃機関用点火装置
EP0532263A1 (fr) * 1991-09-13 1993-03-17 Motorola, Inc. Convertisseur continu-continu
US20040022078A1 (en) * 2002-02-19 2004-02-05 Fairchild Semiconductor Corporation Soft start techniques for control loops that regulate DC/DC converters
EP2071714A1 (fr) * 2006-10-02 2009-06-17 Panasonic Corporation Convertisseur cc/cc

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Publication number Publication date
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