EP2895734B1 - Ignition system for an internal combustion engine - Google Patents

Description

State of the art

The present invention relates to an ignition system for an internal combustion engine. In particular, the present invention relates to an ignition system for internal combustion engines, to which increased requirements by (high) charge and dilute, flame retardant mixtures (λ >> 1, lean-layer concepts, high EGR rates) exist.

GB717676 shows a step-up transformer for an ignition system in which a controlled via a vibration switch circuit part is used in the manner of a boost converter to supply a spark generated by the step-up transformer with electrical energy.

WO 2009/106100 A1 shows a constructed according to a high-voltage capacitor ignition system circuitry in which stored in a capacitor energy is passed on the one hand to the primary side of a transformer and on the other hand via a bypass with a diode on a spark gap.

US 2004/000878 A1 shows an ignition system in which a memory on the secondary side, comprising a plurality of capacitors, is charged in order to supply a spark generated by a transformer with electrical energy.

WO9304279 A1 shows an ignition system with two energy sources. An energy source transmits electrical energy via a transformer to a spark gap, while the second energy source between a secondary side terminal of the transformer and the electrical ground is arranged.

The JP S60 169675 A and the JP H07 174063 A show an ignition system in which a capacitor is charged via a capacitor connected in parallel. As is known, ignition systems for internal combustion engines are based on a high-voltage generator, for example a step-up transformer, by means of which energy originating from the vehicle battery or a generator is converted to high voltages, by means of which a spark gap is supplied in order to ignite a combustible mixture in the internal combustion engine. For this purpose, a current flowing through the step-up transformer is abruptly interrupted, whereupon the energy stored in the magnetic field of the step-up transformer discharges in the form of a spark. In order to ensure the ignition of the combustible mixture particularly reliably, ignition systems are known in the prior art which have a plurality of spark events in succession in order to increase the probability of the presence of an ignitable mixture at the location of one of the spark events.
Another known from the prior art problem is that the entire during the spark impact converted electrical energy must be stored in the high voltage generator, whereby the high voltage generator is comparatively large and thus expensive and takes up much space.
Due to the discharge characteristic of the high-voltage generator, such a high current flows, in particular at the beginning of the spark strike, that the electrodes of the spark gap are eroded. In this case, such a high current to ensure a spark is physically not required. Only the required duration of the spark strike is ensured in this way by accepting the disadvantages described above.
It is therefore an object of the present invention to overcome the aforementioned disadvantages of the prior art.

Disclosure of the invention

The aforementioned object is achieved by an ignition system and a method for generating and maintaining a spark. As is known from the prior art, the ignition system according to the invention also has a high voltage generator, such as a step-up transformer, with a primary side connected to a power source and a secondary side connected to a spark gap. The principle of operation of the high voltage generator corresponds to that known from the prior art, and therefore need not be further explained. Furthermore, a spark gap, likewise known from the prior art, is provided, which is set up to conduct a current transmitted by the high-voltage generator to the secondary side. The spark gap can be arranged, for example, in a spark plug. Since lower voltages are required to maintain an existing arc over the spark gap than for the initial generation of the same, a bypass is provided according to the invention, which can transmit electrical energy from the electrical energy source at the high voltage generator to the secondary side.
As a bypass here is a variety of possible circuits conceivable, of which individual will be discussed in more detail below. To overcome the drawbacks known in the art, the bypass is arranged to sustain longer and more reliably an arc generated by the high voltage generator over the spark gap than would be possible by means of the magnetic energy stored in the high voltage generator. According to the invention, the bypass is adapted to support a decaying electrical signal in the secondary coil of the high voltage generator from a predefined time or from a predefined current intensity of the current. In other words, a logic may be provided in the ignition system according to the invention, which performs a time measurement and / or determines a current intensity and, in response to reaching corresponding predefined reference values, causes the bypass to output a secondary-side electrical signal. In this way, spark duration can preferably be generated between 0.5 ms to 5 ms in the event of spark currents, preferably within the limits of 30 mA to 100 mA of different polarity (polarity of the voltage supply). This offers the advantage of being over the power to be transmitted to the high voltage generator is greatly reduced and thus the initial spark current decreases, whereby spark erosion at the electrodes of the spark gap can be reduced and the high voltage generator can be made significantly smaller than is the case in the prior art.

The dependent claims show preferred developments of the invention.

Preferably, the high voltage generator is configured as a step-up transformer and has a primary coil on the primary side and a secondary coil on the secondary side. Both coils may be magnetically coupled together by means of a transformer core (e.g., sheet iron). In this case, the bypass is arranged to transmit an electrical voltage in addition to the step-up transformer, which adds to a transformer voltage lying across the secondary coil of the step-up transformer. In this way, the bypass allows a "support" of the spark current by an entry of additional electrical energy to the spark gap.

Alternatively, the high voltage generator may be configured as a high voltage capacitor ignition (HCC) system. Such and other systems for high voltage generation and their operation are known and described in the prior art, so that a closer examination is not required here.

More preferably, the bypass one or (advantageously for common handling of the sometimes occurring high voltages) a plurality of energy storage, preferably one or more capacitors, connected in series and / or parallel, capacitances, the first terminal is connected to a secondary side terminal of the high voltage generator and the second terminal is connected to the electrical ground, in particular, an inductance between the power source and the capacitance is provided switchable. In this way, the bypass provides a secondary-side energy storage, by means of which the decaying electrical signal can be supported in the secondary coil of the high voltage generator from a predefined time or from a predefined current. As further explained in connection with the accompanying drawing figures For example, in order to charge the capacitor, an inductance between the power source and the capacitor may be switchably provided. When the switch is closed, the capacitance and the inductance form a resonant circuit, by means of which a temporary increase in the electrical potential at the first terminal of the capacitance is possible. In particular, in the event that a current is first passed through the inductance and a discharge of the stored energy in the inductance is forced to the capacitance, can be provided at suitably selected switching times very high voltages without the required energy within a high voltage generator to have to cache.

More preferably, between the inductance and the capacitance, a non-linear dipole, for example in the form of a diode, can be provided, which has flow direction in the direction of the capacitance. In this way, it is possible to prevent energy from "escaping" from the capacitance in the direction of the inductance when the switch is closed. In the context of the present invention, when a "diode" is mentioned as a non-linear dipole, this is done for reasons of brevity and readability. It will be apparent to those skilled in the art that voltages may sometimes be present across the non-linear dipoles called diode, which may be coped with more conveniently by several components, such as diodes connected in series. In this case, each of the diodes can be configured as a Zener diode. Possibly. For example, an included switch may also be closed in response to a signal when a predefined first current direction is to be expected in the non-linear branch and then opened when a predefined second (oppositely directed) current direction in the nonlinear branch is to be expected. If a plurality of diodes can be advantageously used in the following and high voltages applied, the statements made above also apply accordingly. In particular, a switchable connection between a common connection between the inductance and the diode on the one hand and the electrical ground on the other hand can be provided. In this way, it is possible to provoke a current flow through the inductance when the switch is closed, and to redirect the current through the diode to the capacitance by opening the switch. With a suitable choice of the pulse-pause ratio and / or the drive frequency in this case a high voltage can be generated with very good efficiency.

Further preferably, a current measuring means, for example, between an output terminal of the high voltage generator and the capacitance may be provided, which may be configured for example as a shunt resistor. This current measuring means may further be arranged, for example, between capacitance and ground or in the path of the diode, and be set up to give a signal to a switch in the bypass so that it can react to a critical current intensity in the secondary-side mesh. Alternatively or additionally, an overvoltage protection, for example, a diode may be provided parallel to the capacitance, which protects the capacitance against an overvoltage. For example, a reverse zener diode can be used to relieve excessively high capacitance.
Alternatively or additionally, a voltage measurement and / or a power measurement may be carried out, for example via the capacitance, in order to obtain information about the ignition current and / or the ignition output.

The inductor is designed as a transformer or transformer with a primary side and a secondary side, wherein a first terminal of the primary side is connected to the power source and a second terminal of the primary side is connected via a switch with the electrical ground. Further, a first terminal of the secondary side of the transformer is connected to the power source and a second terminal of the secondary side of the transformer, as described above, connected to the diode. With a suitable choice of the transmission ratio can be used in this way a switch provided on the primary side to switch a secondary side flowing current. Due to the transmission ratio favorable conditions for dimensioning the switch and in this way a safer and more cost-effective implementation of the ignition system according to the invention.
According to another aspect of the present invention, a method for generating a spark for an internal combustion engine is proposed. In this case, a spark by means of an energy source of extracted electrical energy, which is given via a high voltage generator with a primary side and a secondary side to a spark gap is generated first. According to the invention, the spark is maintained by means of electrical energy, which is transmitted from the energy source via a bypass to the secondary side. The electrical energy is provided to maintain the spark as a controlled pulse train, for example in the kilohertz range, preferably between 10kHz and 100kHz, from the power source. In the above-mentioned sampling in the kHz range, it is possible to generate voltages in the range up to several 1000 V at an improved efficiency, which can be used to support the spark, when the stored energy in the high voltage generator is no longer sufficient to the arc to maintain it reliably. In addition to the advantages already mentioned, the application of the present invention offers advantages in terms of the efficiency of the electrical ignition system and new diagnostic capabilities. Both for the basic method according to this aspect of the present invention and for the further developments described below, the statements made in connection with the ignition system according to the invention apply correspondingly.
More preferably, the electrical energy for maintaining the spark is coupled as electrical voltage in series or parallel to the secondary side of the high voltage generator. In other words, a coupling-in section of the bypass in conjunction with the secondary-side coil of the high-voltage generator forms a mesh whose voltage lies parallel to the spark gap.

Brief description of the drawings

Figur 1

ein Zeitdiagramm zum Vergleich sich gemäß dem Stand der Technik und der vorliegenden Erfindung einstellender Zündströme;

Figur 2

ein Schaltbild gemäß einem ersten Ausführungsbeispiel eines nicht erfindungsgemäßen Zündsystems;

Figur 3

Darstellungen von Strom-Zeitdiagrammen sowie zugehöriger Schaltsequenzen für die in Figur 2 gezeigte Schaltung;

Figur 4

ein Schaltbild gemäß einem zweiten Ausführungsbeispiel eines erfindungsgemäßen Zündsystems;

Figur 5

ein Schaltbild gemäß einem dritten Ausführungsbeispiel eines erfindungsgemäßen Zündsystems; und

Figur 6

Darstellungen von Strom-Zeitdiagrammen sowie zugehöriger Schaltsequenzen für die in Figur 4 und Figur 5 gezeigte Schaltung;

Hereinafter, embodiments of the invention will be described in detail with reference to the accompanying drawings. In the drawings:

FIG. 1

a timing chart for comparison according to the prior art and the present invention adjusting ignition currents;

FIG. 2

a circuit diagram according to a first embodiment of a non-inventive ignition system;

FIG. 3

Representations of current-time diagrams and associated switching sequences for the in FIG. 2 shown circuit;

FIG. 4

a circuit diagram according to a second embodiment of an ignition system according to the invention;

FIG. 5

a circuit diagram according to a third embodiment of an ignition system according to the invention; and

FIG. 6

Representations of current-time diagrams and associated switching sequences for the in FIG. 4 and FIG. 5 shown circuit;

Embodiments of the invention

FIG. 1 shows a timing diagram of the ignition current, that of the current which flows when penetrating the spark gap within the secondary-side coil of the step-up transformer as a high voltage generator. In this case, a region 103 is marked, within which the current is so high that the electrodes of the spark plug can be damaged by increased erosion. The region 104 marks those (low) currents within which a required stability of the arc for igniting ignitable mixture can not be guaranteed. Thus, as described in the introduction, a current 100 realized by ignition systems of the prior art runs after a steep rise to the region 103 which endangers the electrodes and subsequently drops essentially linearly (in approximation with an exponential discharge function). On the other hand, the energy conducted to the spark gap according to the present invention divides into two energy components provided by a current flowing through the step-up transformer to generate a spark and a current flowing through the bypass to maintain a spark. After the step-up transformer (smaller in size compared to the prior art) has produced an arc, the current without the bypass according to the invention would steeply decrease (corresponding to the discharge of the small secondary inductance with respect to conventional secondary inductances) (see illustration in FIG FIG. 1 , 101) and would "disappear" shortly after its formation in the area 104. By means of the bypass according to the invention, the current intensity on the secondary side, more precisely, in the spark gap, can be maintained over a much longer time range between the critical regions 103 and 104 (see illustration in FIG FIG. 1 , 102). After switching off the bypass, the energy stored in the secondary coil discharges, as in the prior art, which leads to a steeply falling spark current. This results in a total current, which, however, dips into the unstable region 104 much later than the current intensity 100 of the known ignition system.
FIG. 2 shows a circuit with which the in FIG. 1 illustrated current waveforms 101, 102 can be realized. Shown is an ignition system 1, which comprises a step-up transformer 2 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. 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 Einschaltfunkenunterdrückung, which diode may alternatively be replaced by the diode 21. In a mesh with the secondary coil 9 and the diode 23, a spark gap 6 is provided to ground 14, via which the ignition current i _{2 is} to ignite the combustible gas mixture. There is provided a bypass 7 (surrounded by a dot-dash line) between the electric power source 5 and the secondary side 4 of the step-up transformer 2. For this purpose, an inductor 15 is connected via a switch 22 and a diode 16 to a capacitor 10, one end of which is connected to the secondary coil 9 and the other end to the electrical ground 14. The inductance serves as an energy store in order to maintain a current flow. The diode 16 is oriented in the direction of the capacitance 10 conductive. The structure of the bypass 7 is thus for example comparable to a boost converter. Between the capacitor 10 and the secondary coil 9, a shunt 19 is provided as a current measuring means or voltage measuring means, the measuring signal of the switch 22 and switch 27 is supplied. In this way, the switches 22, 27 are arranged to respond to a defined range of the current intensity i ₂ through the secondary coil 9. The diode 16 facing terminal of the switch 22 is connected via a further switch 27 to the electrical ground 14 connectable. To hedge the capacitor 10, a Zener diode 21 is connected in reverse direction parallel to the capacitor 10. Furthermore, switching signals 28, 29 are indicated, by means of which the switches 22, 27 can be controlled. While the switching signal 28 represents switching on and "staying closed" for an entire ignition cycle, the switching signal 29 outlines a simultaneous alternating signal between "closed" and "open". When the switch 22 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 switches 22, 27 are closed. When the switch 27 is open, the current is conducted to the capacitor 10 via the diode 16 and the connection 35. 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 on the spark gap 6. In this case, however, the capacitor 10 discharges, so that energy 27 can be brought into the magnetic field of the inductor 15 by closing the switch 27 to recharge this energy to the capacitor 10 at a reopening of the switch 27. It can be seen that the control 31 of the switch 30 provided in the primary side 3 is kept considerably shorter than is the case for the switches 22 and 27. These processes are associated with FIG. 3 discussed in more detail. Since the switch 22 does not assume a decisive function for the processes according to the invention, but merely switches the circuit on or off, this is merely optional and can therefore also be dispensed with.

FIG. 3 shows in the diagram a a short and steep rise of the primary coil current i _ZS , which occurs during the time in which the switch 30 (see diagram 3c) is in the ON state. When the switch 30 is switched off, the primary coil current i _ZS drops to 0 A. Diagram b shows the profiles of the secondary coil current i ₂ , as they are suitable for use of the in FIG. 2 shown system with (301) and without (300) Bypass. As soon as the primary coil current i _ZS due to an opening of the switch 30 to 0 results and thus discharges the magnetic energy stored in the step-up transformer in the form of an arc over the spark gap 6, a secondary coil current i ₂ , which quickly without bypass (300) against 0 drops. In contrast, by a closed switch 22 (see diagram d) and a pulse-shaped control (see diagram e, switching signal 29) of Switch 27 a substantially constant secondary coil current i ₂ (301) over the spark gap 6 driven. Wherein the secondary current i ₂ depends on the burning voltage at the spark gap 6 and is assumed here for the sake of simplicity of a constant burning voltage. Only after interruption of the bypass 7 by opening the switch 22 and opening the switch 27 now also the secondary coil current i ₂ drops to 0 from. It can be seen from diagram b) that the respective falling edge is delayed by a time t _{HSS_a} . The total time during which the bypass is used is _denoted as t _HSS and the time period during which energy is given to the upstream side of the step-up transformer 2 is t _i . The starting time of t _HSS opposite t _i can be chosen variable.

FIG. 4 shows one opposite FIG. 2 Alternative and inventive embodiment of a circuit of an ignition system 1 according to the present invention. At the entrance of the circuit, in other words at the connection to the electrical energy source 5, a fuse 26 is provided. To stabilize the input voltage beyond a capacitance 17 is provided parallel to the input of the circuit or parallel to the electric power source 5. Furthermore, the inductance 15 has been replaced by a transformer having a primary side 15_1 and a secondary side 15_2, the primary side 15_1 having a primary coil and the secondary side 15_2 having a secondary coil. The first terminals of the transformer are respectively connected to the electric power source 5 and the fuse 26. In this case, a second terminal of the primary side 15_1 is connected via a switch 27 to the electrical ground 14. The second terminal of the secondary side 15_2 of the transformer 15 is now connected directly to the diode 16 without a switch. Due to the transmission ratio, a switching operation by the switch 27 in the branch of the primary side 15_1 also acts 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 15, can be found for switching operations more favorable dimensions for the switch 27. For example, lower switching voltages can be realized, whereby the dimensioning of the switch 27 is simpler and less expensive. The switch 27 is controlled via a drive 24, which is connected via a driver 25 to the switch 27. As in FIG. 2 a shunt 19 is provided to the secondary side current i ₂ and the To measure voltage across the capacitance 10 and provide this or the driver 24 of the switch 27. Moreover, the control 24 receives a control signal s _HSS . On the one hand, the introduction of energy via the bypass into the secondary side can be switched on and off via this. It is also possible to control the power of the electrical variable introduced through the bypass or into the spark gap, in particular via the frequency and / or the pulse-pause ratio via a suitable control signal. Optionally, a non-linear dipole, symbolized below by a high-voltage diode 33, are connected in parallel to the secondary-side coil of the boost converter. This high-voltage diode 33 bridges the high-voltage generator 2 on the secondary side, whereby the energy supplied by the bypass 7 in the form of a boost converter (surrounded by a dot-dash line) is conducted directly to the spark gap 6 without being led through the secondary coil 9 of the high voltage generator 2. Thus, no losses on the secondary coil 9 and the efficiency increases. The remaining elements of in FIG. 4 The drawings shown correspond to those as shown in FIG FIG. 2 shown and discussed above.

FIG. 5 shows an alternative embodiment of the in FIG. 4 featured circuit. This is a high-voltage diode 33 with flow direction to the spark gap between the energy storage 10 of the bypass 7 in the form of a boost converter (surrounded by a dotted line) and the spark gap 6 is arranged. As a result, the high voltage diode 33 bridges the high voltage generator 2 on the secondary side, whereby the energy supplied by the bypass 7 is led directly to the spark gap 6, without being guided by the secondary coil 9 of the high voltage generator 2. Thus, no losses on the secondary coil 9 and the efficiency increases.

FIG. 6 shows time diagrams for a) the ignition coil current i _ZS , b) the bypass current i _HSS , c) the output voltage across the spark gap 6, d) the secondary coil current i ₂ for the in FIG. 4 shown ignition system without (501) and with (502) using the bypass according to the invention, e) the switching signal 31 of the switch 30 and f) the switching signal 32 of the switch 27 for the pulse signal in the bypass 7. Zu already in connection with FIG. 3 The diagrams shown are referred to the above discussion for the sake of brevity.

Diagram b) also illustrates the current consumption of the bypass 7 according to the invention, which comes about through a pulse-shaped actuation of the switch 27. In practice, 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. By way of example, the integer multiples of 10,000 Hz in the range between 10 and 100 kHz may be mentioned as possible range limits. To control the power delivered to the spark gap, it is advisable to control the pulse-pause ratio of the signal 29 or 32, in particular stepless, in order to produce a corresponding output signal. In addition, it is also possible to increase the voltage supplied by the electrical energy source by means of an additional DC-DC converter before it is further processed in the bypass according to the invention. It should be noted that concrete interpretations depend on many circuit-inherent and external constraints. It does not present to the skilled person any unreasonable problems of self-design for his purpose and for the constraints which he has to take into account.

It is a core idea of the present invention to advantageously split two functions which have combined the step-up transformers of known ignition systems in accordance with the invention, in order to allow suitable dimensioning of the high-voltage generator and more efficient utilization of the electrical energy. For this purpose, a high voltage generator is provided to generate a spark according to the prior art. A bypass is set up to maintain the existing arc over the spark gap. For this purpose, a bypass takes energy from, for example, the same energy source as the primary side of the high voltage generator and uses this to support the decaying edge of the transformer voltage and thus to delay its drop below the burning voltage. The skilled artisan recognizes preferred embodiments of the bypass according to the invention as working in the manner of a boost converter circuit structures. In this case, the input of the boost converter is connected in parallel to the electrical energy source, while the output of the boost converter is arranged in series or parallel to the secondary coil of the high voltage generator. The term "energy source" is to be interpreted broadly within the scope of the present invention and may include other energy conversion devices (eg, DC-DC converters). It is also apparent to those skilled in the art that the inventive idea is not limited to an objective energy source.
Although the aspects and advantageous embodiments of the invention have been described in detail with reference to the embodiments explained in connection with the accompanying drawings, modifications and combinations of features of the illustrated embodiments are possible for the skilled person, without departing from the scope of the present invention, the scope of protection the appended claims are defined.

Claims (14)

1. Ignition system (1) for generating an ignition spark in a spark gap (6) of an internal combustion engine, comprising

   - a first input connection (5) for connection to an energy source (5) and a high-voltage output (34) for connection to the spark gap (6),

   - at least one high-voltage generator (2) with a primary side (3) and a secondary side (4) in each case,

   - a bypass (7) for transmitting electrical energy to the secondary side (4) of the high-voltage generator (2), wherein the bypass (7) is set up to support a decaying electrical signal in a secondary coil (9) of the high-voltage generator (2) as of a predefined time or as of a predefined current intensity of the current,

   - wherein the bypass (7) is electrically connected to the first input connection (5) and comprises one or more capacitances (10) as energy stores (10) and a switch (27), wherein energy can be transmitted from the electrical energy source (5) to the high-voltage output (34) by means of pulsed control of the switch (27),

   characterized in that

   - the bypass (7) additionally has an inductance (15) and a diode (16), wherein

   - a first connection of the inductance (15) is connected to the energy source (5) and a second connection of the inductance (15) is connected to a first connection of the diode (16), wherein

   - the switch (27) is set up to connect the second connection or a third connection of the inductance (15) to the electrical earth (14),

   - a second connection of the diode (16) is connected to a first connection of the energy store (10), and

   - a second connection of the energy store (10) is connected to the electrical earth (14), and a Zener diode (21), in particular, is connected in parallel with the capacitance (10), wherein

   - the inductance (15) is in the form of a transformer having a primary side (15_1) and a secondary side (15_2), wherein a first connection of the primary side (15_1) is connected to the energy source (5) and a second connection of the primary side (15_1) is connected to the electrical earth (14) via a switch (27), and wherein a first connection of the secondary side (15_2) is connected to the energy source (5) and a second connection of the secondary side (15_2) is connected to the first non-linear two-terminal network (16).
2. Ignition system according to Claim 1, wherein the energy provided via the bypass can be transmitted until the pulsed control of the switch (27) of the bypass has been concluded.
3. Ignition system according to Claim 1, also comprising
   a means for measuring current (19) and/or for measuring voltage and/or for measuring power, which means transmits a measurement signal to a controller (24) controlling the switch (27).
4. Ignition system according to Claim 1 or 3, wherein

   - the high-voltage generator (2) is in the form of a step-up transformer and has a primary coil (8) on the primary side,

   - the bypass (7) is set up to generate a voltage which is added to a voltage across the secondary coil (9) or is fed in in parallel with the secondary coil (9), and, in particular,

   - an input capacitance (17) is provided in parallel with the energy source (5).
5. Ignition system according to one of the preceding claims, wherein the bypass (7) contains an energy store (10), for example a capacitance, wherein, in particular, its

   - first connection is connected to a secondary-side connection of the high-voltage generator (2), and its

   - second connection is connected to the electrical earth (14), wherein, an inductance (15), in particular, is provided between the energy source (5) and the energy store (10), preferably in a switchable manner.
6. Ignition system according to one of the preceding claims, wherein a first non-linear two-terminal network (16), for example in the form of a first diode, is provided between the inductance (15) and the energy store (10), which two-terminal network has a flow direction in the direction of the capacitance (10), and wherein the switch (27) is provided between a common connection (35) of the inductance (15) and the first non-linear two-terminal network (16), on the one hand, and the electrical earth (14), on the other hand.
7. Ignition system according to Claim 6, wherein the switch (22, 27) is a transistor.
8. Ignition system according to one of the preceding claims, wherein

   - a shunt resistor for measuring the ignition current or the voltage across the energy store (10) is provided as a means for measuring current (19) and/or for measuring voltage and/or for measuring power, which shunt resistor is set up to provide a signal for controlling at least one switch (22, 27) in the bypass (7), and/or

   - a second non-linear two-terminal network (21), in particular in the form of a second diode, in parallel with the energy store (10) protects the latter from an overvoltage.
9. Ignition system according to one of the preceding claims, wherein the bypass (7) comprises a boost converter and/or the high-voltage generator (2) is bridged, on the secondary side, by a third non-linear two-terminal network (33), in particular in the form of a third diode.
10. Method for operating an ignition system, wherein the ignition system comprises

    - a first input connection (5) for connection to an energy source (5) and a high-voltage output (34) for connection to the spark gap (6),

    - at least one high-voltage generator (2) with a primary side (3) and a secondary side (4) in each case,

    - a bypass (7) for transmitting electrical energy to the secondary side (4) of the high-voltage generator (2), wherein the bypass (7) is set up to support a decaying electrical signal in a secondary coil (9) of the high-voltage generator (2) as of a predefined time or as of a predefined current intensity of the current, wherein the bypass is electrically connected to the first input connection (5) and comprises one or more capacitances as energy stores (10) and a switch (27),

    - wherein the bypass (7) additionally has an inductance (15) and a diode (16), wherein a first connection of the inductance (15) is connected to the energy source (5) and a second connection of the inductance (15) is connected to a first connection of the diode (16), wherein the switch (27) is set up to connect the second connection or a third connection of the inductance (15) to the electrical earth (14), wherein a second connection of the diode (16) is connected to a first connection of the energy store (10) and a second connection of the energy store (10) is connected to the electrical earth (14), and a Zener diode (21), in particular, is connected in parallel with the capacitance (10), wherein the inductance (15) is in the form of a transformer having a primary side (15_1) and a secondary side (15_2), wherein a first connection of the primary side (15_1) is connected to the energy source (5) and a second connection of the primary side (15_1) is connected to the electrical earth (14) via a switch (27), and wherein a first connection of the secondary side (15_2) is connected to the energy source (5) and a second connection of the secondary side (15_2) is connected to the first non-linear two-terminal network (16),

    characterized in that
    the switch (27) is controlled in a pulsed manner via a signal (29, 32), and in that the power of the energy transmitted by the bypass (7) is controlled using the frequency and/or the pulse-pause ratio of the switch (27).
11. Method according to Claim 10, characterized in that the switching frequency is, in particular, in the kilohertz range, preferably between 10 kHz and 100 kHz.
12. Method according to Claim 10, characterized in that the energy provided via the bypass (7) is transmitted until the pulsed control of the switch (27) has been concluded.
13. Method according to Claim 10, characterized in that the electrical energy for maintaining the ignition spark is coupled in as an electrical voltage in series or in parallel with the secondary side (4) of the high-voltage generator (2).
14. Method according to Claim 10, comprising the steps of:

    - outputting a signal to a switch (27) in the bypass and, on the basis of the signal,

    - reacting to a critical current intensity in the secondary-side mesh.

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