JP6125139B1 - Internal combustion engine ignition device - Google Patents

Abstract

An ignition device for an internal combustion engine, wherein the DC booster circuit has a value substantially equal to an amount of increase in the applied voltage of the ripple suppression capacitor due to energy being charged at the time of dielectric breakdown with respect to the applied voltage target value of the ripple suppression capacitor. The output voltage command value for the DC booster circuit is controlled so that the output voltage is lowered.

Description

  The present invention relates to an internal combustion engine ignition device mounted on a vehicle or the like.

  As is well known, lean combustion methods that burn lean fuel and exhaust gas recirculation (EGR: Exhaust) that recirculates exhaust gas after fuel combustion into the combustion chamber are methods for improving the fuel efficiency of internal combustion engines mounted on vehicles and the like. Gas circulation) method, or a method of making the combustion chamber have a high compression ratio, etc., are being promoted, but each method has a problem that it is difficult to ignite the fuel steadily, and improves the ignitability of the internal combustion engine. It is requested.

  Conventionally, as one method for improving the ignitability in an internal combustion engine ignition device, there is a high-frequency plasma ignition device disclosed in Patent Document 1, for example. A general internal combustion engine ignition device generates a high voltage by a high voltage power source for dielectric breakdown composed of an ignition coil and an igniter, and generates a spark discharge between electrodes of a spark plug, This high-frequency plasma ignition device has a high-frequency AC power supply in addition to a high-voltage power supply for dielectric breakdown, and supplies a high-frequency voltage between the electrodes of the spark plug immediately after the start of discharge by the high-voltage power supply for dielectric breakdown. By continuously generating high-pressure, high-frequency plasma, the ignitability of the fuel gas is enhanced.

Japanese Patent Laying-Open No. 2015-86702

  In the high-frequency plasma ignition device disclosed in Patent Document 1, a high-voltage transmission path output from a high-voltage power supply and a high-frequency AC voltage transmission path output from a high-frequency AC power supply are combined into one transmission path for ignition. Connected to the plug. The high-frequency AC power supply is separated from the high voltage output from the dielectric breakdown power supply at the ignition timing by a resonance capacitor that forms a resonance circuit.

  In the conventional internal combustion engine ignition device configured as described above, the dielectric breakdown in the combustion chamber is caused by the voltage between the electrodes of the ignition plug reaching the discharge start voltage, and the resonance capacitor in the resonance circuit is also ignited. A voltage equivalent to the voltage between the electrodes of the plug is applied. The electric charge charged in the resonance capacitor flows into the high-frequency AC power source as a capacitive discharge current at the same time as dielectric breakdown occurs. As a result, the potential inside the high-frequency AC power supply rises, which may cause an increase in power loss and overvoltage breakdown of circuit elements.

  The present invention has been made in order to solve the above-mentioned problems in the conventional internal combustion engine ignition device, and the capacitance discharged from the resonance capacitor of the resonance circuit at the time of dielectric breakdown between the electrodes of the ignition plug. An object of the present invention is to provide an internal combustion engine ignition device having a function of preventing an overvoltage breakdown of a circuit element while reducing a power loss caused by a potential increase inside a high-frequency AC power source of the ignition device due to a discharge current.

An internal combustion engine ignition device according to the present invention includes:
A spark plug provided in the internal combustion engine and provided with at least a pair of electrodes facing each other through a gap;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC boost circuit is controlled based on the output voltage command value from the control circuit so as to output the DC power according to the target voltage applied value of the ripple suppression capacitor,
The control circuit includes:
The output voltage of the DC booster circuit is a value substantially equal to the amount of increase in the applied voltage of the ripple suppressing capacitor due to the energy being charged at the time of dielectric breakdown with respect to the applied voltage target value of the ripple suppressing capacitor. Configured to control the output voltage command value for the DC booster circuit to be low,
It is characterized by that.

An internal combustion engine ignition device according to the present invention is
A spark plug provided in the internal combustion engine and provided with at least a pair of electrodes facing each other through a gap;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A DC step-down circuit comprising a semiconductor switch and stepping down a DC voltage charged in the ripple suppression capacitor;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC booster circuit can be controlled based on the output voltage command value from the control circuit so that the DC power is output according to the target voltage value applied to the ripple suppression capacitor. Composed of
The DC step-down circuit is
The ON / OFF operation of the semiconductor switch of the DC step-down circuit can be controlled by the control circuit so as to step down the energy charged in the ripple suppression capacitor and regenerate the DC power supply ,
When the applied voltage of the ripple suppression capacitor is larger than the output voltage command value of the DC boost circuit, the DC step-down circuit steps down the energy charged in the ripple suppression capacitor to the output voltage of the DC power supply. Configured to regenerate to DC power supply,
It is characterized by that.
Furthermore, an internal combustion engine ignition device according to the present invention includes:
A spark plug provided in the internal combustion engine and provided with at least a pair of electrodes facing each other through a gap;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A DC step-down circuit comprising a semiconductor switch and stepping down a DC voltage charged in the ripple suppression capacitor;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC booster circuit can be controlled based on the output voltage command value from the control circuit so that the DC power is output according to the target voltage value applied to the ripple suppression capacitor. Composed of
The DC step-down circuit is
The ON / OFF operation of the semiconductor switch of the DC step-down circuit can be controlled by the control circuit so as to step down the energy charged in the ripple suppression capacitor and regenerate the DC power supply,
When the switching circuit does not output an AC voltage every ignition cycle of the internal combustion engine, the DC voltage step-down circuit steps down the energy charged in the ripple suppression capacitor to the output voltage of the DC power supply and supplies it to the DC power supply. Configured to regenerate,
It is characterized by that.

  According to the internal combustion engine ignition device of the present invention, the high-frequency AC power source includes a DC power source and a semiconductor switch, and the DC voltage boosts the output voltage of the DC power source by controlling the on / off operation of the semiconductor switch. A booster circuit, a ripple suppression capacitor that suppresses ripple of the DC voltage output from the DC booster circuit, and a plurality of semiconductor switches, and the on / off operation of the semiconductor switch is controlled to control the DC booster circuit. A switching circuit that converts the output DC power into AC power, a resonance circuit that includes at least one inductor and at least one capacitor and resonates the AC current output from the switching circuit, the DC boost circuit, and the switching Control for controlling the on / off operation of each of the semiconductor switches of the circuit. The ripple suppression capacitor is charged with energy of a capacitive discharge current discharged from the capacitor included in the resonance circuit when a dielectric breakdown occurs between the electrodes of the spark plug, and the DC boost The circuit controls the on / off operation of the semiconductor switch of the DC booster circuit based on the output voltage command value from the control circuit so as to output the DC power according to the target voltage applied to the ripple suppression capacitor. The control circuit has a value substantially equal to an amount of increase in the applied voltage of the ripple suppression capacitor due to the energy being charged at the time of the dielectric breakdown with respect to the applied voltage target value of the ripple suppression capacitor. The output voltage command value for the DC boost circuit is controlled so that the output voltage of the DC boost circuit is lowered. The power generated by the potential rise inside the high-frequency AC power supply is controlled by controlling the operation of the semiconductor switch that constitutes the DC booster circuit and the DC stepdown circuit according to the operating state of the internal combustion engine and the ignition device. Overvoltage breakdown of the circuit element can be prevented while reducing loss.

  According to the internal combustion engine ignition device of the present invention, the high-frequency AC power source includes a DC power source and a semiconductor switch, and the output voltage of the DC power source is boosted by controlling the on / off operation of the semiconductor switch. A DC booster circuit, a ripple suppression capacitor that suppresses a ripple of a DC voltage output from the DC booster circuit, a DC switch that includes a semiconductor switch, and that steps down the DC voltage charged in the ripple suppression capacitor, A switching circuit that converts the DC power output from the DC booster circuit into AC power by controlling the on / off operation of the semiconductor switch, and at least one inductor and at least one capacitor. Including a resonance circuit for resonating the alternating current output from the switching circuit. And a control circuit that controls the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit, and the ripple suppression capacitor has a dielectric breakdown between the electrodes of the spark plug. The energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged, and the DC boost circuit outputs the DC power according to the target voltage applied to the ripple suppression capacitor. The on / off operation of the semiconductor switch of the DC boost circuit is controlled based on the output voltage command value from the control circuit, and the DC voltage down circuit performs the ignition of the internal combustion engine only by the dielectric breakdown power source. The control circuit reduces the energy charged in the ripple suppression capacitor and regenerates it to the DC power supply. Since the ON / OFF operation of the semiconductor switch of the DC booster circuit is controlled, the energy charged in the ripple suppression capacitor is regenerated to the DC power supply to prevent overvoltage breakdown of the circuit element. However, it is possible to reduce the power consumption of the ignition device.

It is a circuit diagram which shows the circuit structure of the internal combustion engine ignition device by Embodiment 1 of this invention. FIG. 3 is a timing diagram illustrating an operation sequence of the internal combustion engine ignition device according to Embodiment 1 of the present invention. It is a figure which shows the circuit structure of the internal combustion engine ignition device by Embodiment 2 of this invention. It is a circuit diagram which shows the circuit structure of the internal combustion engine ignition device by the modification of Embodiment 2 of this invention. It is a timing diagram explaining the operation | movement sequence of the internal combustion engine ignition device by Embodiment 2 of this invention. It is a circuit diagram which shows an example of a structure of the switching circuit of the internal combustion engine ignition device by Embodiment 3 of this invention.

Embodiment 1 FIG.
1 is a circuit diagram showing a circuit configuration of an internal combustion engine ignition device according to Embodiment 1 of the present invention. In FIG. 1, the internal combustion engine ignition device according to the first embodiment of the present invention includes a spark plug 1, a high-frequency AC power source 2, and a dielectric breakdown power source 3.

  The high-frequency AC power source 2 includes a DC power source 4 composed of a battery or the like mounted on a vehicle, a DC booster circuit 5 that boosts the output voltage of the DC power source 4, a ripple suppression capacitor 6 that suppresses the ripple voltage, and an AC voltage that is AC. Switching circuit 7 for converting to voltage, DC booster circuit 5, control circuit 8 for controlling the operation of a semiconductor switch described later included in switching circuit 7, and AC booster circuit 9 for boosting an AC voltage output from switching circuit 7 And a resonance circuit 10 that shapes the voltage waveform output from the switching circuit 7 into a sine wave.

  The DC booster circuit 5 is configured by a boost chopper circuit as an example, a coil 51 having one end connected to the positive electrode side of the DC power supply 4, a diode 52 having one end connected to the other end of the coil, and the coil 51 and the diode 52. And a semiconductor switch 53 connected between the series connection point of the DC power supply 4 and the negative electrode side of the DC power supply 4. The semiconductor switch 53 includes an internal diode connected in reverse parallel or an external diode connected in reverse parallel. The DC booster circuit 5 only needs to boost the DC voltage of the DC power supply 4, and may have a configuration other than the boost chopper circuit shown in FIG.

  The switching circuit 7 is composed of a full-bridge inverter circuit, and includes four semiconductor switches 71, 72, 73, and 74 that include built-in diodes connected in reverse parallel or external diodes connected in reverse parallel. The switching circuit 7 only needs to have a function of converting a DC voltage into an AC voltage, and may have a configuration other than the full bridge inverter circuit shown in the figure.

  The AC booster circuit 9 includes a primary coil 91 connected between AC terminals of the switching circuit 7 and a secondary coil 92 magnetically coupled to the primary coil 91. The resonance circuit 10 includes an LC series resonance circuit in which a resonance capacitor 11 and a resonance inductor 101 are connected in series. The other end of the resonant inductor 101 is connected to one end of the secondary coil 92 of the AC boost circuit 9.

  The spark plug 1 includes a pair of electrodes opposed via a gap, and a secondary coil 92 of the AC booster circuit 9 is connected between these electrodes via a resonance circuit 10. The dielectric breakdown power supply 3 applies a voltage of several tens [kV] between the electrodes of the spark plug 1 in accordance with an ignition timing signal to be described later, thereby causing a dielectric breakdown in the gap between the electrodes of the spark plug and spark discharge. Is generated.

  In the case of an ignition device for an internal combustion engine mounted on a vehicle, a battery is normally used as the DC power source 4, and a spark discharge is generated between the electrodes of the spark plug 1 with a voltage of about 12 [V] of the battery. Therefore, in the first embodiment shown in FIG. 1, an AC booster circuit 9 that boosts the AC voltage is inserted after the switching circuit 7.

  When high-frequency plasma is generated in the spark plug 1, the value of the output voltage output between the output terminals of the high-frequency AC power supply 2 is the input of the switching circuit 7 applied between the input terminals of the switching circuit 7 by the ripple suppression capacitor 6. It becomes equal to a value obtained by multiplying the voltage value by the boosting ratio of the AC boosting circuit 9 and becomes equal to or higher than the discharge sustaining voltage of the spark plug 1. If the value of the input voltage applied between the input terminals of the switching circuit 7 by the ripple suppression capacitor 6 is equal to or higher than the aforementioned discharge sustain voltage, the AC booster circuit 9 may not be provided in the high-frequency AC power supply 2.

  As described above, the resonance circuit 10 uses the LC series resonance circuit in which the resonance capacitor 11 and the resonance inductor 101 are connected in series. However, a configuration in which at least one inductor and at least one capacitor are combined. A similar ignition operation can also be performed using this resonance circuit.

  First, the basic operation of the internal combustion engine control apparatus according to Embodiment 1 of the present invention configured as described above will be described. In FIG. 1, the internal combustion engine ignition device is insulated from the output voltage of the high-frequency AC power supply 2 in accordance with an ignition timing signal for each ignition cycle output from an engine control unit (hereinafter referred to as ECU) (not shown). By applying the output voltage of the power source 3 for destruction between the electrodes of the spark plug 1, a spark discharge is generated between the electrodes of the spark plug 1 to ignite the air-fuel mixture in the combustion chamber of the internal combustion engine. I do.

  Specifically, the DC booster circuit 5 boosts the output voltage of the DC power supply 4 to the applied voltage target value V1 of the ripple suppression capacitor 6 prior to generation of the ignition timing signal by the ECU, and the ripple suppression capacitor 6 is previously set in advance. Is charged to the applied voltage target value V1. That is, the control circuit 8 performs on / off control of the semiconductor switch 53 of the DC booster circuit 5 based on the output voltage command value V2 for the DC booster circuit 5 generated prior to the generation of the ignition timing signal from the ECU. The output voltage of the power supply 4 is boosted.

  Here, the output voltage command value V2 for the DC booster circuit 5 described above matches the applied voltage target value V1 of the ripple suppression capacitor 6, and the ripple suppression capacitor 6 applies the applied voltage prior to the generation of the ignition timing signal. The target value V1 is charged. The applied voltage target value V1 is an arbitrary value set so that the output voltage of the high-frequency AC power supply 2 is equal to or higher than the discharge sustaining voltage of the spark plug 1.

  Next, the dielectric breakdown power supply 3 applies a voltage of several tens [kV] to the spark plug 1 in accordance with the ignition timing signal generated from the ECU, thereby causing a dielectric breakdown between the electrodes of the spark plug 1 and spark discharge. Give rise to After dielectric breakdown between the electrodes of the spark plug 1, the high frequency AC power supply 2 outputs the DC voltage applied with the ripple suppression capacitor 6 as a high frequency AC voltage by the switching circuit 7. The high-frequency AC voltage output from the switching circuit 7 is boosted by the AC boost circuit 9 as necessary.

  The high-frequency AC power source 2 shapes the AC voltage boosted by the AC booster circuit 9 into a sine wave by the resonance circuit 10 and has a high frequency of several [MHz] having a voltage value from several hundreds [V] to several [kV]. An AC voltage is applied to the spark plug 1 to perform high frequency plasma ignition on the fuel / air mixture in the cylinder of the internal combustion engine.

  The internal combustion engine ignition device repeats the above-described operation at every ignition timing of the internal combustion engine. However, the internal combustion engine ignition device may operate so as to perform ignition only by spark ignition by the dielectric breakdown power source 3 in accordance with the operating state of the internal combustion engine.

  Next, the operation of the internal combustion engine ignition device according to Embodiment 1 of the present invention will be described in detail. FIG. 2 is a timing chart for explaining an operation sequence of the internal combustion engine ignition device according to the first embodiment of the present invention. A is an “ignition timing signal”, B is a “capacitance discharge current”, and C is a “high-frequency AC power supply”. ”,“ D ”indicates“ output voltage command value for DC booster circuit ”, and E indicates“ applied voltage of ripple suppression capacitor ”.

  1 and 2, the internal combustion engine ignition device receives the ignition timing signal A from the ECU at time t0 to operate the dielectric breakdown power source 3 and several 10 [ A high voltage of kV] is applied to cause dielectric breakdown between the electrodes of the spark plug 1. At this time, a voltage equal to the interelectrode voltage of the spark plug 1 is applied to the resonance capacitor 11 constituting the resonance circuit 10. The energy stored in the resonant capacitor 11 is released as a capacitive discharge current shown in FIG. 2B that vibrates at the resonant frequency created by the resonant capacitor 11 and the resonant inductor 101 simultaneously with the dielectric breakdown between the electrodes of the spark plug 1.

  The capacitive discharge current flows into the output terminal which is the AC side terminal of the switching circuit 7 via the AC boosting circuit 9 of the high frequency AC power supply 2 and raises the potential of the portion where the current flows. Here, as in the case where the switching circuit 7 is composed of the full-bridge inverter shown in FIG. 1, the semiconductor switches 71, 72, 73, 74 are connected in reverse-parallel connected diodes or reverse-parallel connected external diodes. However, when the capacitor discharge current is connected in the forward direction from the inflow portion of the capacitive discharge current, the capacitive discharge current flows into the ripple suppression capacitor 6 via the built-in diode or the external diode.

  Thereby, the energy of the capacitive discharge current is charged to the ripple suppression capacitor 6 via the switching circuit 7. If the applied voltage of the ripple suppression capacitor 6 at the time t0 matches the applied voltage target value V1 of the ripple suppression capacitor 6, due to the inflow of the capacity discharge current, the ripple suppression capacitor 6 at the time t1. The applied voltage increases by an applied voltage increase amount ΔV1a.

  Next, at time t2, the output current C of the high-frequency AC power source 2 is output from the high-frequency AC power source 2 to the spark plug 1, and the high-frequency plasma is generated between the electrodes of the spark plug 1 from time t2 to time t3. Is generated. As a result, the energy stored in the ripple suppression capacitor 6 is consumed, so that the voltage applied to the ripple suppression capacitor 6 at time t3 when the high-frequency AC power supply 2 stops outputting the high-frequency current as the output current C is applied. The voltage drop amount is reduced by ΔV1b. At this time, in the high-frequency AC power supply 2, since the applied voltage of the ripple suppression capacitor 6 is higher than the applied voltage target value V1, a larger power loss occurs than when operating at the applied voltage target value V1.

  At an arbitrary time t4 before the next ignition timing t6, the DC booster circuit 5 starts boosting the output voltage of the DC power supply 4 to the output voltage command value V2, and the ripple suppression capacitor 6 Charge (time t4). In the internal combustion engine ignition device, the applied voltage increase ΔV1a due to the capacitive discharge current is detected until the next high-frequency alternating current is output, and the applied voltage of the ripple suppression capacitor 6 matches the applied voltage target value V1. Thus, the output voltage command value of the DC booster circuit 5 is controlled. Specifically, the applied voltage of the ripple suppression capacitor 6 before the inflow of the capacitive discharge current (time t0) and before the high-frequency alternating current output (time t2) is measured, and the applied voltage of the ripple suppression capacitor 6 is increased by the capacitive discharge current. The amount ΔV1a is detected, and the value V2 obtained by subtracting the applied voltage increase amount ΔV1a from the applied voltage target value V1 of the ripple suppression capacitor 6 is charged by the DC voltage booster circuit after the capacitive discharge current flows (time t1). At any timing up to the start (time t4), the output voltage command value of the DC booster circuit 5 is set. Therefore, a value V2 obtained by subtracting the applied voltage increase amount ΔV1a from the applied voltage target value V1 is equal to the output voltage command value.

  At time t6 that is the next ignition timing, the capacitive discharge current flows into the ripple suppression capacitor 6 again. If the energy of the capacitive discharge current is constant regardless of the ignition cycle, the applied voltage of the ripple suppression capacitor 6 is set to the output voltage command value for the DC booster circuit 5 set as V2, and the applied voltage increase Δ due to the capacitive discharge current Δ V1a is equal to the added value, and coincides with the applied voltage target value V1 of the ripple suppression capacitor 6 at time t7.

  In addition, even when the capacity discharge current is different for each ignition timing, the energy of the capacity discharge current does not change sharply. Therefore, by controlling the output voltage command value of the DC booster circuit 5, The difference between the actual applied voltage to the ripple suppression capacitor 6 and the applied voltage target value V1 is smaller than that in the condition where the control is not performed.

  As described above, by controlling the output voltage command value of the DC booster circuit 5, it is possible to suppress an increase in potential inside the high-frequency AC power supply 2 due to the inflow of the capacity discharge current, and to prevent an increase in power loss. .

  Further, when the applied voltage of the ripple suppression capacitor 6 is higher than the applied voltage target value V1, the DC booster circuit 5 may stop the operation of the semiconductor switch 53 and stop the boosting operation. Thereby, the switching loss of the semiconductor switch 53 and the conduction loss which arises in each element which comprises the semiconductor switch 53 can be reduced.

  Furthermore, the output current value of the high frequency AC power supply 2 or the pressure of the internal combustion engine indicates that the output voltage of the high frequency AC power supply 2 does not reach the discharge maintaining voltage of the spark plug 1 and that high frequency plasma cannot be generated between the electrodes of the spark plug 1. When detected from the information, the applied voltage target value V1 of the ripple suppression capacitor 6 or the output voltage command value of the DC booster circuit 5 may be increased so that ignition can be ensured.

  In this case, if the DC booster circuit 5 is configured by a boost chopper circuit as shown in FIG. 1, the control circuit 8 reduces the on-duty of the semiconductor switch 53 in accordance with the applied voltage increase ΔV1a due to the capacitive discharge current. The output voltage of the DC booster circuit 5 is set to the output voltage command value. When the applied voltage of the ripple suppression capacitor 6 does not reach the applied voltage target value V1 even if the capacitive discharge current flows into the ripple suppression capacitor 6 due to the decrease of the capacitive discharge current, the control circuit 8 applies the application by the capacitive discharge current. The on-duty of the semiconductor switch 53 is increased according to the voltage increase amount ΔV1a, and the output voltage of the DC booster circuit 5 is set to a new output voltage command value.

  Since the value of the capacity discharge current, the value of the output current of the high-frequency AC power supply 2 or the output period (the time corresponding to the time t2 to the time t3 in FIG. 2) varies depending on the operating state of the internal combustion engine and the ignition device, The circuit 8 may control the output voltage command value of the DC booster circuit 5 between the time t1 and the time t4 for each ignition cycle, or the applied voltage increase ΔV1a at a plurality of ignition timings. It may be averaged and used to control the output voltage command value of the DC booster circuit 5.

  Further, as described above, the control circuit 8 does not control the DC booster circuit 5 after detecting that the applied voltage of the ripple suppression capacitor 6 has fluctuated due to the capacitive discharge current, but instead of controlling the DC booster circuit 5. Even if the predicted value ΔV1a1 of the applied voltage increase amount due to the capacity discharge current is calculated based on the operating condition, and the semiconductor switch 53 of the DC booster circuit 5 is controlled based on the calculated predicted value ΔV1a1 of the applied voltage increase amount. Good. The specific example in that case is shown below.

That is, the control circuit 8, the output voltage maximum value of the breakdown power supply 3, i.e. detects the breakdown voltage V _b, the electrostatic capacitance C _s of the breakdown voltage V _b and the resonant capacitor 11, the energy of the capacitive discharge current W _cd is calculated based on the following equation (1).

The control circuit 8, and the energy W _cd of capacitive discharge current which is calculated by the equation (1), than the capacitance C _r of the ripple suppression capacitor 6, the prediction of the applied voltage increase of the ripple suppression capacitor 6 by inflow of capacitive discharge current The value ΔV1a1 is calculated based on the following equation (2).

  The control circuit 8 controls the above-described DC booster circuit 5 using the predicted value ΔV1a1 of the increase amount of the applied voltage of the ripple suppression capacitor 6. That is, in FIG. 2, the internal combustion engine ignition device uses the value V2 obtained by subtracting the predicted value ΔV1a1 of the increase in applied voltage from the applied voltage target value V1 of the ripple suppression capacitor 6 as a new output voltage of the DC booster circuit 5. Set to the command value.

ここで、ｄは点火プラグ１の電極間距離、ＡとＢは電極間に存在する気体の持つ定数、γは電極を構成する金属の二次電子放出係数、ｌｎは自然対数である。The control circuit 8 calculates the breakdown voltage _Vb of the spark plug 1 by the following equation (3) based on the cylinder pressure p of the internal combustion engine acquired from the ECU, and uses this to calculate the energy W of the capacity discharge current. _cd may be obtained. The following equation (3) is a calculation formula of the breakdown voltage V _b by Paschen's law.

Here, d is the distance between the electrodes of the spark plug 1, A and B are constants of the gas existing between the electrodes, γ is the secondary electron emission coefficient of the metal constituting the electrode, and ln is the natural logarithm.

When the gas in the internal combustion engine and the spark plug 1 are specified, the dielectric breakdown voltage _Vb is determined by the cylinder pressure p. Accordingly, the control circuit 8, the cylinder pressure p in the memory in the control circuit 8 advance the relationship between the breakdown voltage V _b prerecorded, breakdown voltage V _b in accordance with the cylinder pressure p of the pressure sensor detects The predicted value ΔV1a1 of the applied voltage increase amount of the ripple suppression capacitor 6 is calculated using the above formulas (1) and (2), and this calculated predicted value ΔV1a1 of the applied voltage increase amount is calculated. Can be used to control the DC booster circuit 5.

The control circuit 8 may record in advance in the memory a relationship between the maximum value and the breakdown voltage V _b of the capacitive discharge current, reads the breakdown voltage V _b corresponding to the maximum value of the capacitive discharge current, capacitive discharge current seeking energy W _cd, it may calculate the predicted value △ V1a1 of the applied voltage increase of the ripple suppression capacitor 6.

Embodiment 2. FIG.
FIG. 3 is a diagram showing a circuit configuration of an internal combustion engine ignition device according to Embodiment 2 of the present invention. The internal combustion engine ignition device according to the second embodiment of the present invention uses the energy charged in the ripple suppression capacitor 6 between the DC power supply 4 and the ripple suppression capacitor 6 in the internal combustion engine ignition device according to the first embodiment described above. A DC step-down circuit 12 having a function of stepping down to the power source voltage of the DC power source 4 and regenerating to the DC power source 4 is inserted, and the operation of the semiconductor switch 121 included in the DC step-down circuit 12 is controlled by the control circuit 8. It is a thing.

  In FIG. 3, the DC step-down circuit 12 uses a step-down chopper circuit as an example, and has one end connected to the positive electrode side of the DC power supply 4 and one end connected to the other end of the coil 123. The semiconductor switch 121 connected to the diode 122, the series connection point of the coil 123 and the diode 122, and the positive electrode side terminal of the ripple suppression capacitor 6 is provided. The semiconductor switch 121 includes a built-in diode connected in reverse parallel or an external diode connected in reverse parallel. The DC step-down circuit 12 only needs to be able to step down a DC voltage, and may have a configuration other than the step-down chopper circuit shown in FIG.

  The rest of the configuration of the internal combustion engine ignition device according to the second embodiment is the same as that of the first embodiment and includes all the configuration of the internal combustion engine ignition device according to the first embodiment. It is possible to carry out almost the same control as in FIG.

  In FIG. 3, the DC booster circuit 5 and the DC step-down circuit 12 are separately configured. However, as shown in FIG. 4, the DC booster circuit 5 and the DC step-down circuit 12 are configured by a single bidirectional DC voltage conversion circuit 13 having a bidirectional output. It is also possible to reduce the number of parts. 4 is a circuit diagram showing a circuit configuration of a modified example of the internal combustion engine ignition device according to Embodiment 2 of the present invention.

  4, the bidirectional DC voltage conversion circuit 13 includes a coil 134 having one end connected to the positive electrode side of the DC power supply 4, a semiconductor switch 131 having one end connected to the other end of the coil 134, and a coil 134. A semiconductor switch 132 having one end connected to the connection point with the semiconductor switch 131 and the other end connected to the negative electrode side of the DC power supply 4 is provided. The semiconductor switches 131 and 132 include built-in diodes connected in reverse parallel or external diodes connected in reverse parallel. The operations of the semiconductor switches 131 and 132 are controlled by the control circuit 8.

  The general operation of the internal combustion engine ignition device according to the second embodiment shown in FIG. 3 and the internal combustion engine ignition device according to the modification of the second embodiment shown in FIG. 4 are the same as the operation of the internal combustion engine ignition device according to the first embodiment. It is. That is, also in the internal combustion engine ignition device according to the second embodiment and its modified example, as in the case of the internal combustion engine ignition device according to the first embodiment, the applied voltage of the ripple suppression capacitor 6 increases due to the inflow of the capacitive discharge current. To do.

  In the internal combustion engine ignition device according to the second embodiment and the modification thereof, the voltage applied to the ripple suppression capacitor 6 is a DC boost circuit 5 (in the case of the second embodiment) or a bidirectional DC voltage conversion circuit (a modification of the second embodiment). When it is larger than the output voltage command value in the case of the example), the energy charged in the ripple suppression capacitor 6 is stepped down to the output voltage of the DC power supply 4 and regenerated in the DC power supply 4. As a result, excess energy charged in the ripple suppression capacitor 6 is regenerated in the DC power source 4, so that overvoltage breakdown of the circuit elements can be prevented while reducing power loss due to increase in applied voltage.

  Next, the operation of the internal combustion engine ignition apparatus according to Embodiment 2 of the present invention shown in FIG. 3 will be described based on an operation sequence. The operation of the internal combustion engine ignition device according to the modification of the second embodiment of the present invention shown in FIG. 4 is the same as this. FIG. 5 is a timing chart for explaining an operation sequence of the internal combustion engine ignition device according to the second embodiment of the present invention. A is an “ignition timing signal”, B is a “capacitance discharge current”, and C is a “high-frequency AC power supply”. ”And“ D ”indicate“ applied voltage of the ripple suppression capacitor ”. FIG. 5 shows an example of the operation for regenerating energy to the DC power supply 4 when the energy of the output current of the high-frequency AC power supply 2 is smaller than the energy of the capacitive discharge current flowing into the ripple suppression capacitor 6. 2 shows the timing operation of the internal combustion engine ignition device.

  In FIG. 5, from time t0 to time t2, the operation is the same as in the case of the first embodiment, and the ripple suppression capacitor 6 is charged with the energy of the capacitive discharge current. Increases by the applied voltage increase amount ΔV2a. At time t2, a high-frequency alternating current is output from the high-frequency alternating current power source 2 to the spark plug 1 and energy stored in the ripple suppression capacitor 6 is consumed. Therefore, at time t3 when the output of the high-frequency current is stopped. The applied voltage of the ripple suppression capacitor 6 is reduced by the voltage drop amount ΔV2b.

  When the voltage drop amount ΔV2b is smaller than the applied voltage increase amount ΔV2a, the ripple suppression capacitor 6 is applied with a voltage larger than the applied voltage target value V1. If this state continues, the voltage applied to the ripple suppression capacitor 6 gradually increases at each ignition timing, which may cause an increase in power loss and overvoltage breakdown of circuit elements. Therefore, when a voltage greater than the target voltage V1 applied to the ripple suppression capacitor is applied to the ripple suppression capacitor 6, the DC step-down circuit 12 is configured so that the applied voltage of the ripple suppression capacitor 6 and the target voltage target value V1 match. By controlling the semiconductor switch and regenerating the energy charged in the ripple suppression capacitor 6 to the DC power supply 4, it is possible to reduce loss of the high-frequency AC power supply 2 and prevent overvoltage breakdown of the circuit elements. In FIG. 5, this control is performed at an arbitrary time t4.

  Further, as in the case of the first embodiment, the control circuit 8 does not perform control after receiving the potential fluctuation of the DC voltage path due to the capacity discharge current, but in advance from the operating conditions of the internal combustion engine and the ignition device. The predicted value ΔV2a1 of the amount of increase in the voltage applied to the ripple suppression capacitor 6 due to the discharge current and the output current of the high-frequency AC power supply 2 may be calculated to control the semiconductor switches of the DC step-down circuit 12 and the DC step-up circuit 5.

As a specific example, as in the case of the first embodiment, for example, the energy W _cd possessed by the capacitive discharge current is calculated from the dielectric breakdown voltage V _b between the electrodes of the spark plug 1 and the capacitance of the resonant capacitor 11. Based on the calculated value and the capacitance of the ripple suppression capacitor 6, a predicted value ΔV2a1 of the amount of increase in applied voltage when flowing into the ripple suppression capacitor 6 is calculated.

  Further, in the operation mode of the internal combustion engine, when the switching circuit 7 of the high frequency AC power source 2 does not perform DC / AC power conversion at every ignition timing of the ignition cycle, that is, the high frequency AC power source 2 is stopped for dielectric breakdown. There are cases where ignition is performed only by the power source 3. At this time, the capacity discharge current flows into the ripple suppression capacitor 6 at every ignition timing of the ignition cycle, and the applied voltage of the ripple suppression capacitor 6 increases, which may cause overvoltage breakdown of the circuit elements. Here, the control circuit 8 controls the semiconductor switch constituting the DC step-down circuit 12 so that the energy charged in the ripple suppression capacitor 6 is stepped down to the output voltage of the DC power source 4 and regenerated to the DC power source 4. As a result, it is possible to reduce the power consumption of the ignition device while preventing overvoltage breakdown of the circuit elements.

  In addition, when the operation of the internal combustion engine is stopped, the control circuit 8 reduces the energy charged in the ripple suppression capacitor 6 to the output voltage of the DC power supply 4 and regenerates it to the DC power supply 4. By controlling the semiconductor switch that constitutes 12, the power consumption of the ignition device can be reduced.

Embodiment 3 FIG.
6 is a circuit diagram showing an example of the configuration of a switching circuit of an internal combustion engine ignition device according to Embodiment 3 of the present invention. In FIG. 6, in the internal combustion engine ignition device according to the third embodiment of the present invention, when the capacitive discharge current flows into the switching circuit 7 simultaneously with the dielectric breakdown, the semiconductor switches 71, 72, 73, 74 are The circuit configuration is such that the current detection means 21 can detect the inflowing current. Other configurations are the same as those in the first or second embodiment.

  In FIG. 6, as an example of the switching circuit 7, a full bridge inverter is used by four semiconductor switches 71, 72, 73, 74 configured by MOS-FETs. However, as long as the switching circuit 7 is composed of a semiconductor switch having a built-in diode in the forward direction or an external anti-parallel diode with respect to the ripple suppression capacitor 6 from the portion where the capacitive discharge inflow flows, what kind of circuit can be used? It may be used.

  In FIG. 6, a shunt resistor is used as an example of the current detection means 21. However, any device may be used as long as the current value of the capacitive discharge current and the polarity of the current can be detected. For example, a current transformer may be used. .

  The apparatus operation according to Embodiment 3 of the present invention will be described in detail. The capacitive discharge current flows into the switching circuit 7 as an alternating current having the resonance frequency of the resonance circuit 10. The capacitive discharge current flows into the ripple suppression capacitor 6 via the built-in diodes of the semiconductor switches 71 and 73 in the upper arm of the switching circuit 7. Here, the current detection means 21 detects the inflow of the capacitive discharge current into the built-in diodes of the semiconductor switches 71 and 73 of each upper arm, and at the same time, the semiconductor switch of the arm in which the inflow of the capacitive discharge current is confirmed is turned on to perform synchronous rectification I do.

  As a result, power loss can be reduced as compared with the case where the capacitive discharge current flows only into the built-in diode of the semiconductor switch. This control is effective when the product of the on-resistance of the semiconductor switch and the capacitive discharge current is small with respect to the forward voltage of the built-in diode of the semiconductor switch.

The internal combustion engine ignition device according to the first to third embodiments of the present invention described above embodies at least one corresponding invention among the inventions described in (1) to (16).
(1) a spark plug provided in the internal combustion engine and provided with at least a pair of electrodes facing each other with a gap therebetween;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC boost circuit is controlled based on the output voltage command value from the control circuit so as to output the DC power according to the target voltage applied value of the ripple suppression capacitor,
The control circuit includes:
The DC booster circuit is a value substantially equal to the amount of increase in the applied voltage of the ripple suppressing capacitor due to the energy being charged when the dielectric breakdown occurs with respect to the applied voltage target value of the ripple suppressing capacitor. Is configured to control the output voltage command value for the DC booster circuit so that the output voltage of
An internal combustion engine ignition device.
According to the present invention, it is possible to prevent the overvoltage breakdown of the circuit element while reducing the power loss caused by the potential increase inside the high-frequency AC power supply.
Power loss due to voltage can be reduced.

(2) a spark plug provided in the internal combustion engine and provided with at least a pair of electrodes facing each other with a gap therebetween;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A DC step-down circuit comprising a semiconductor switch and stepping down a DC voltage charged in the ripple suppression capacitor;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC booster circuit can be controlled based on the output voltage command value from the control circuit so that the DC power is output according to the target voltage value applied to the ripple suppression capacitor. Composed of
The DC step-down circuit is
The ON / OFF operation of the semiconductor switch of the DC step-down circuit can be controlled by the control circuit so as to step down the energy charged in the ripple suppression capacitor and regenerate the DC power supply ,
When the applied voltage of the ripple suppression capacitor is larger than the output voltage command value of the DC boost circuit, the DC step-down circuit steps down the energy charged in the ripple suppression capacitor to the output voltage of the DC power supply. Configured to regenerate to DC power supply,
An internal combustion engine ignition device.
According to the present invention, the energy charged in the ripple suppression capacitor is regenerated to the DC power source, so that the power consumption of the ignition device can be reduced while preventing overvoltage breakdown of the circuit elements. Further, according to the present invention, the energy of the excess voltage charged in the ripple suppression capacitor can be regenerated to the DC power supply, which contributes to the reduction of power consumption. In addition, it is possible to prevent element destruction due to application of overvoltage in the vicinity of the ripple suppression capacitor.
(3) a spark plug provided in the internal combustion engine and provided with at least a pair of electrodes opposed via a gap;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A DC step-down circuit comprising a semiconductor switch and stepping down a DC voltage charged in the ripple suppression capacitor;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC booster circuit can be controlled based on the output voltage command value from the control circuit so that the DC power is output according to the target voltage value applied to the ripple suppression capacitor. Composed of
The DC step-down circuit is
The ON / OFF operation of the semiconductor switch of the DC step-down circuit can be controlled by the control circuit so as to step down the energy charged in the ripple suppression capacitor and regenerate the DC power supply,
When the switching circuit does not output an AC voltage every ignition cycle of the internal combustion engine, the DC voltage step-down circuit steps down the energy charged in the ripple suppression capacitor to the output voltage of the DC power supply and supplies it to the DC power supply. Configured to regenerate,
An internal combustion engine ignition device.
According to the present invention, when the energy charged in the ripple suppression capacitor is not used, it can be regenerated to the power source.

( 4 ) The DC boost circuit and the DC step-down circuit are configured by a single DC voltage conversion circuit having a bidirectional output.
The internal combustion engine ignition device according to (2) or (3) , wherein
According to the present invention, the number of components can be reduced and the size can be reduced by integrating the DC boost circuit and the DC voltage down circuit.

( 5 ) The control circuit
The DC booster circuit has a value substantially equal to the amount of increase in the applied voltage of the ripple suppressing capacitor due to the energy being charged when the dielectric breakdown occurs with respect to the applied voltage target value of the ripple suppressing capacitor. It is configured to control the output voltage command value for the DC boost circuit so that the output voltage becomes low.
The internal combustion engine ignition device according to any one of (2) to (4) , wherein
According to the present invention, power loss due to voltage can be reduced.

( 6 ) The control circuit
The output voltage command value for the DC boost circuit is controlled at any timing from the inflow of the capacitive discharge current to the ripple suppression capacitor to the start of charging of the ripple suppression capacitor by the DC boost circuit. It is configured,
The internal combustion engine ignition device according to any one of (1) to ( 5 ) above,
According to the present invention, power loss due to voltage can be reduced.

( 7 ) An AC booster circuit having a function of boosting an AC voltage output from the switching circuit is provided between the switching circuit and the resonance circuit.
The internal combustion engine ignition device according to any one of (1) to ( 6 ), wherein:
According to the present invention, it is possible to reliably generate the output voltage necessary for the sustaining voltage. In addition, a semiconductor switch that can operate at high speed and low breakdown voltage can be used for the switching circuit.

( 8 ) The applied voltage target value of the ripple suppression capacitor is set to be equal to or higher than the discharge sustaining voltage between the electrodes of the spark plug.
The internal combustion engine ignition device according to any one of (1) to ( 7 ), characterized in that:
According to this invention, ignition can be performed reliably.

( 9 ) The value obtained by multiplying the applied voltage target value of the ripple suppression capacitor by the boost ratio of the AC boost circuit is set to be equal to or higher than the discharge sustaining voltage between the electrodes of the spark plug.
The internal combustion engine ignition device described in ( 7 ) above,
According to this invention, ignition can be performed reliably.

( 10 ) When the control circuit detects that the high-frequency plasma cannot be maintained between the electrodes of the spark plug with the output voltage of the high-frequency AC power supply, the control circuit increases the applied voltage target value for the ripple suppression capacitor. Configured to,
The internal combustion engine ignition device according to any one of (1) to ( 9 ), wherein:
According to the present invention, it is possible to prevent the applied voltage of the ripple suppression capacitor from being lowered until it falls below the discharge sustaining voltage.

( 11 ) The control circuit compares the applied voltage of the ripple suppression capacitor before and after the occurrence of the dielectric breakdown, and the capacitance discharge current discharged from the capacitor included in the resonance circuit is charged. Configured to measure the applied voltage increase of the ripple suppression capacitor,
The internal combustion engine ignition device according to any one of (1) or ( 5 ) to ( 10 ) above, wherein
According to the present invention, the amount of increase in the applied voltage of the ripple suppression capacitor can be obtained from actual measurement and used for feedback control of the output voltage command value of the DC booster circuit.

( 12 ) The control circuit calculates the energy of the capacitive discharge current based on a capacitance value of a capacitor included in the resonance circuit and the dielectric breakdown voltage applied between the electrodes of the spark plug, Based on the calculated capacity discharge current energy and the capacitance of the ripple suppression capacitor, the applied voltage increase amount of the ripple suppression capacitor is calculated,
The internal combustion engine ignition device according to any one of (1) or ( 5 ) to ( 10 ) above, wherein
According to the present invention, the amount of increase in the voltage applied to the ripple suppression capacitor can be calculated from the capacitance and the dielectric breakdown voltage, and used for feedback or feedforward control of the output voltage command value of the DC booster circuit.

( 13 ) The control circuit is configured to calculate the breakdown voltage of the spark plug based on a distance between the electrodes of the spark plug and a pressure in the cylinder of the internal combustion engine. The internal combustion engine ignition device according to ( 12 ) above.
According to the present invention, the dielectric breakdown voltage can be calculated from the internal pressure of the container of the internal combustion engine and used for the control of the invention described in (10) above.

( 14 ) The control circuit is configured to stop the on / off operation of the semiconductor switch constituting the DC boost circuit when the applied voltage of the ripple suppression capacitor is higher than the output voltage command value of the DC boost circuit. Being
The internal combustion engine ignition device according to any one of (1) to ( 13 ), characterized in that:
According to the present invention, power loss can be reduced by stopping the operation of unnecessary semiconductor switches.

( 15 ) When the capacitive discharge current discharged from the capacitor included in the resonant circuit flows into the switching circuit when the dielectric breakdown occurs between the electrodes, the control circuit may receive the capacitive discharge current that flows into the switching circuit. The semiconductor switch of the switching circuit is configured to be turned on / off so as to perform synchronous rectification.
The internal combustion engine ignition device according to any one of (1) to ( 14 ), wherein: According to the present invention, the conduction loss of the semiconductor switch can be reduced by synchronous rectification.

( 16 ) When the internal combustion engine stops operating, the DC step-down circuit is configured to step down the energy charged in the ripple suppression capacitor to the output voltage of the DC power source and regenerate the DC power source. ing,
It internal combustion engine ignition device according to one any of the above (2), wherein (5) the.
According to the present invention, the energy consumed in the circuit when the internal combustion engine is stopped can be regenerated to the power source.

  The internal combustion engine ignition device according to the present invention described above may use any combination of the configuration and control used in the first to third embodiments. The internal combustion engine control device according to the present invention is an ignition device other than the internal combustion engine mounted on the vehicle as long as the energy discharged from the resonance capacitor of the resonance circuit simultaneously with the dielectric breakdown flows into the capacitor as a capacitive discharge current. The present invention may be applied to any internal combustion engine.

  The internal combustion engine ignition device according to the present invention can be used in the field of an internal combustion engine ignition device for igniting an internal combustion engine mounted on an automobile or the like, and thus in the field of a vehicle such as an automobile.

DESCRIPTION OF SYMBOLS 1 Spark plug, 2 High frequency alternating current power supply, 3 Dielectric breakdown power supply, 4 DC power supply, 5 DC booster circuit, 51, 123, 134 Coil, 52, 122 Diode, 53, 71, 72, 73, 74, 121, 131, 132 Semiconductor Switch, 6 Ripple Suppression Capacitor, 7 Switching Circuit, 8 Control Circuit, 9 AC Booster Circuit, 10 Resonant Circuit, 11 Resonant Capacitor, 101 Resonant Inductor, 12 DC Step-Down Circuit, 13 Bidirectional DC Voltage Converter, 21 Current Detection means, V1 applied voltage target value, △ V1a, △ V2a applied voltage increment, △ V1b, △ V2b applied voltage reduction amount, _{V b} breakdown voltage, the capacitance of _{C s} resonant _capacitor, the energy of the _{W cd} capacitive discharge current , the capacitance of _{C r} ripple suppression capacitor, △ V1a1, △ V2a1 applied voltage increase in predicted values, p shea Sunda the pressure, d the distance between the electrodes, A, constant with the gas present between the B electrodes, the secondary electron emission coefficient of the metal constituting the γ electrode, ln natural logarithm.

Claims (16)

A spark plug provided in the internal combustion engine and provided with at least a pair of electrodes facing each other through a gap;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC boost circuit is controlled based on the output voltage command value from the control circuit so as to output the DC power according to the target voltage applied value of the ripple suppression capacitor,
The control circuit includes:
The DC booster circuit is a value substantially equal to the amount of increase in the applied voltage of the ripple suppressing capacitor due to the energy being charged when the dielectric breakdown occurs with respect to the applied voltage target value of the ripple suppressing capacitor. Is configured to control the output voltage command value for the DC booster circuit so that the output voltage of
An internal combustion engine ignition device. A spark plug provided in the internal combustion engine and provided with at least a pair of electrodes facing each other through a gap;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A DC step-down circuit comprising a semiconductor switch and stepping down a DC voltage charged in the ripple suppression capacitor;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC booster circuit can be controlled based on the output voltage command value from the control circuit so that the DC power is output according to the target voltage value applied to the ripple suppression capacitor. Composed of
The DC step-down circuit is
The ON / OFF operation of the semiconductor switch of the DC step-down circuit can be controlled by the control circuit so as to step down the energy charged in the ripple suppression capacitor and regenerate the DC power supply ,
When the applied voltage of the ripple suppression capacitor is larger than the output voltage command value of the DC boost circuit, the DC step-down circuit steps down the energy charged in the ripple suppression capacitor to the output voltage of the DC power supply. Configured to regenerate to DC power supply,
An internal combustion engine ignition device. A spark plug provided in the internal combustion engine and provided with at least a pair of electrodes facing each other through a gap;
A dielectric power supply that causes a dielectric breakdown between the electrodes by applying a dielectric breakdown voltage between the pair of electrodes of the spark plug;
A high-frequency AC power source capable of generating a high-frequency plasma between the pair of electrodes by applying a high-frequency voltage between the electrodes of the spark plug;
An internal combustion engine ignition device having
The high-frequency AC power supply is
DC power supply,
A DC booster circuit that includes a semiconductor switch and boosts the output voltage of the DC power supply by controlling the on / off operation of the semiconductor switch;
A ripple suppression capacitor for suppressing ripples of DC voltage output from the DC booster circuit;
A DC step-down circuit comprising a semiconductor switch and stepping down a DC voltage charged in the ripple suppression capacitor;
A switching circuit that includes a plurality of semiconductor switches, and that converts DC power output from the DC booster circuit into AC power by controlling on / off operation of the semiconductor switches;
A resonance circuit including at least one inductor and at least one capacitor and resonating an alternating current output from the switching circuit;
A control circuit for controlling the on / off operation of each of the semiconductor switches of the DC booster circuit and the switching circuit;
With
The ripple suppression capacitor is
When dielectric breakdown occurs between the electrodes of the spark plug, the energy of the capacitive discharge current discharged from the capacitor included in the resonance circuit is charged,
The DC booster circuit is
The on / off operation of the semiconductor switch of the DC booster circuit can be controlled based on the output voltage command value from the control circuit so that the DC power is output according to the target voltage value applied to the ripple suppression capacitor. Composed of
The DC step-down circuit is
The ON / OFF operation of the semiconductor switch of the DC step-down circuit can be controlled by the control circuit so as to step down the energy charged in the ripple suppression capacitor and regenerate the DC power supply,
When the switching circuit does not output an AC voltage every ignition cycle of the internal combustion engine, the DC voltage step-down circuit steps down the energy charged in the ripple suppression capacitor to the output voltage of the DC power supply and supplies it to the DC power supply. Configured to regenerate,
An internal combustion engine ignition device. The DC booster circuit and the DC step-down circuit are configured by a single DC voltage conversion circuit having a bidirectional output.
The internal combustion engine ignition device according to claim 2 or 3, characterized by the above. The control circuit includes:
The DC booster circuit has a value substantially equal to the amount of increase in the applied voltage of the ripple suppressing capacitor due to the energy being charged when the dielectric breakdown occurs with respect to the applied voltage target value of the ripple suppressing capacitor. It is configured to control the output voltage command value for the DC boost circuit so that the output voltage becomes low.
The internal combustion engine ignition device according to any one of claims 2 to 4, wherein The control circuit includes:
The output voltage command value for the DC boost circuit is controlled at any timing from the inflow of the capacitive discharge current to the ripple suppression capacitor to the start of charging of the ripple suppression capacitor by the DC boost circuit. It is configured,
The internal combustion engine ignition device according to any one of claims 1 to 5, wherein An AC booster circuit having a function of boosting an AC voltage output from the switching circuit is provided between the switching circuit and the resonance circuit.
The internal combustion engine ignition device according to any one of claims 1 to 6, wherein the ignition device is an internal combustion engine ignition device. The applied voltage target value of the ripple suppression capacitor is set to be equal to or higher than the sustaining voltage between the electrodes of the spark plug,
The internal combustion engine ignition device according to any one of claims 1 to 7, wherein A value obtained by multiplying an applied voltage target value of the ripple suppression capacitor by a boost ratio of the AC boost circuit is set to be equal to or higher than a sustaining voltage between the electrodes of the spark plug.
The internal combustion engine ignition device according to claim 7 . The control circuit is configured to increase the applied voltage target value for the ripple suppression capacitor when detecting that the high-frequency plasma cannot be maintained between the electrodes of the spark plug with the output voltage of the high-frequency AC power supply. ing,
The internal combustion engine ignition device according to any one of claims 1 to 9, wherein The control circuit compares the voltage applied to the ripple suppression capacitor before and after the occurrence of the dielectric breakdown, and the ripple suppression capacitor is charged by a capacitive discharge current discharged from a capacitor included in the resonance circuit. Configured to measure the amount of increase in applied voltage of the
The internal combustion engine ignition device according to any one of claims 1 and 5 to 10 . The control circuit calculates the energy of the capacitive discharge current based on a capacitance value of a capacitor included in the resonance circuit and the dielectric breakdown voltage applied between the electrodes of the spark plug, and calculates the calculated It is configured to calculate the amount of increase in the applied voltage of the ripple suppression capacitor based on the energy of the capacity discharge current and the capacitance of the ripple suppression capacitor.
The internal combustion engine ignition device according to any one of claims 1 and 5 to 10 . The control circuit is configured to calculate the breakdown voltage of the spark plug based on a distance between the electrodes of the spark plug and an in-cylinder pressure of the internal combustion engine.
The internal combustion engine ignition device according to claim 12 . The control circuit is configured to stop the on / off operation of a semiconductor switch constituting the DC boost circuit when an applied voltage of the ripple suppression capacitor is higher than an output voltage command value of the DC boost circuit. ,
The internal combustion engine ignition device according to any one of claims 1 to 13, wherein the ignition device is an internal combustion engine ignition device. The control circuit synchronously rectifies the inflowing capacitive discharge current when a capacitive discharge current discharged from a capacitor included in the resonance circuit flows into the switching circuit when the dielectric breakdown occurs between the electrodes. Configured to turn on / off the semiconductor switch of the switching circuit,
The internal combustion engine ignition device according to any one of claims 1 to 14 , wherein the ignition device is an internal combustion engine ignition device. When the internal combustion engine stops operating, the DC step-down circuit is configured to step down the energy charged in the ripple suppression capacitor to the output voltage of the DC power source and regenerate the DC power source.
The internal combustion engine ignition device according to any one of claims 2 to 5 , wherein the ignition device is an internal combustion engine ignition device.

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