WO2018021464A1 - Electromagnetic wave oscillation device comprising booster circuit - Google Patents

Abstract

The present invention addresses the problem of providing an electromagnetic wave oscillation device that makes it possible to cancel reflected waves and automatically control impedance matching even when an electromagnetic wave emitted from an electromagnetic wave oscillator is reflected. An electromagnetic wave oscillation device is provided with: an electromagnetic wave oscillator 3 that uses voltage applied from a power source P to emit an electromagnetic wave; a resistor 2 that receives the supply of electromagnetic wave energy from the electromagnetic wave oscillator 3; a detector 4 that detects the phase and the amplitude of a reflected wave from the resistor 2; and a control device 5 that controls the electromagnetic wave oscillator 3 and the detector 4. A modulator 31 for modulating the phase and the amplitude of electromagnetic waves from the electromagnetic wave oscillator 3 and an amplifier 32 for amplifying electromagnetic waves are arranged between the electromagnetic wave oscillator 3 and the detector 4. The control device 5 is used to control the modulator 31 so as to obtain a generated waveform in which a waveform having a phase and an amplitude that take conjugated values with respect to the phase and the amplitude of the waveform of a reflected wave detected by the detector 4 is added by vector addition to (combined with) a basic waveform emitted by the electromagnetic wave oscillator 3.

Description

Electromagnetic oscillation device including a booster circuit

The present invention relates to an electromagnetic wave oscillation device that supplies an electromagnetic wave to an ignition device or an electromagnetic wave irradiation antenna.

The present inventors have proposed an ignition device using electromagnetic waves as an ignition device for ignition of an internal combustion engine. For example, as a plasma generator that can be used as an ignition device for a small internal combustion engine that can efficiently generate, expand, and maintain plasma using only electromagnetic waves, an electromagnetic wave oscillator that oscillates electromagnetic waves and an electromagnetic wave oscillator There has been proposed an ignition device that integrally forms a control device to be controlled, a booster circuit including a resonance circuit capacitively coupled to an electromagnetic wave oscillator, and a discharge electrode that discharges a high voltage generated by the booster circuit (for example, Patent Document 1). reference.). In addition, a plasma generating apparatus that maintains and expands plasma by irradiating the plasma of a general spark plug with microwaves has also been proposed.

In addition, an electromagnetic wave absorber that generates heat by absorbing electromagnetic waves is mixed into the purification catalyst disposed in the exhaust passage of the internal combustion engine, and the electromagnetic wave (microwave) is irradiated to the purification catalyst from the electromagnetic wave irradiation antenna. A purification device that is activated in a short time has been proposed. Further, in recent years, an apparatus using a semiconductor oscillator has been proposed from a magnetron in an electromagnetic wave cooking apparatus, a so-called microwave oven.

International Publication No. 2014/115707

Incidentally, the electromagnetic wave supplied to the ignition device described in Patent Document 1 is oscillated in pulses from an electromagnetic wave oscillator. The electromagnetic wave oscillated from the electromagnetic wave oscillator is an electromagnetic wave of several W, and this electromagnetic wave is amplified by an amplifier and supplied to an ignition device or an electromagnetic wave irradiation antenna. Specifically, a DC power source (12V or 24V) from a power source (battery) is supplied to an electromagnetic wave oscillator and an amplifier as continuous 32V by a booster circuit (for example, a DC / DC converter), and the electromagnetic wave oscillator controls When an electromagnetic wave oscillation signal (for example, TTL signal) is received from the device, an electromagnetic wave is oscillated with a pattern in which a predetermined duty ratio, pulse time, etc. are set, and predetermined power (for example, 1 kW) is supplied by an amplifier to which a high voltage of 32 V is constantly applied. And is supplied to an ignition device or an electromagnetic wave irradiation antenna.

However, when the electromagnetic wave oscillated from the electromagnetic wave oscillator irradiates the object to be heated in the cavity serving as the resistance portion from the electromagnetic wave irradiation antenna, impedance matching is lost and a reflected wave is generated when a discharge occurs in the ignition device. When such a reflected wave flows to the electromagnetic wave oscillator, the device may be damaged. Therefore, a circulator or the like is used so that the reflected wave does not flow to the electromagnetic wave oscillator side. However, the use of a circulator, which is a device that prevents reflected waves from flowing to the electromagnetic wave oscillator, raises the price of the entire device and supplies appropriate electromagnetic energy to the resistance unit. There is a problem that can not be.

The present invention has been made in view of such a point, and the object thereof is to generate an electromagnetic wave oscillation that can cancel the reflected wave and automatically control impedance matching even when the electromagnetic wave oscillated from the electromagnetic wave oscillator is reflected. Is to provide a device.

The first invention made to solve the above problems is
An electromagnetic wave oscillation device that supplies an electromagnetic wave to a resistance unit that receives supply of electromagnetic wave energy,
An electromagnetic wave oscillator that oscillates an electromagnetic wave by a voltage applied from a power supply;
A detector for detecting the phase and amplitude of the reflected wave from the resistance unit;
A controller for controlling the electromagnetic wave oscillator and the detector,
A modulator for modulating the phase and amplitude of the electromagnetic wave from the electromagnetic wave oscillator and an amplifier for amplifying the electromagnetic wave are disposed;
The control device controls the modulator so that a waveform having a phase and amplitude taking conjugate values is added to the basic waveform by vector addition to the phase and amplitude of the reflected wave waveform detected by the detector. Like to do.

The electromagnetic wave oscillation device according to the first aspect of the present invention is a generated waveform obtained by vector addition (synthesis) of a waveform having a phase and amplitude taking conjugate values with respect to a phase and amplitude of a reflected wave waveform detected by a detector. By oscillating, the reflected wave can be canceled and impedance matching can be achieved.

The second invention made to solve the above problems is
An electromagnetic wave oscillation device that supplies an electromagnetic wave to a resistance unit that receives supply of electromagnetic wave energy,
An electromagnetic wave oscillator that oscillates an electromagnetic wave by a voltage applied from a power supply;
A detector for detecting the phase and amplitude of the reflected wave from the resistance unit;
A controller for controlling the electromagnetic wave oscillator and the detector,
The electromagnetic wave from the electromagnetic wave oscillator is branched, and a modulator that modulates the phase and amplitude of the electromagnetic wave and an amplifier that amplifies the electromagnetic wave are disposed on each line, and the branched line is connected to the resistance unit via a coupler. And
The control device controls at least one of the modulators branched so as to obtain a phase and amplitude waveform that takes a conjugate value with respect to the phase and amplitude of the reflected wave waveform detected by the detector. Yes.

In the electromagnetic wave oscillation device of the second invention, the path for oscillating the basic waveform and the waveform for oscillating the conjugate waveform taking the conjugate value of the reflected wave are separated.

The electromagnetic wave oscillating device of the present invention is a device for generating plasma with electromagnetic waves (microwaves), even if the plasma fluctuates due to pressure / flow and environmental pressure / flow / temperature when the plasma is generated, and reflection of electromagnetic waves occurs. It is possible to reduce the reflected wave on the line by generating a waveform that takes a conjugate value with respect to the amplitude and phase of the reflected wave and giving a signal that cancels the reflected wave, and by reducing the reflected wave, the connector -It is possible to suppress the discharge / overheating of the line and to effectively suppress the breakage of the equipment.

It is the schematic of the electromagnetic wave oscillation apparatus of this 1st invention, and shows the example whose resistance part is an ignition device. It is the schematic of the same electromagnetic wave oscillation apparatus, and the example whose resistance part is a to-be-heated object by electromagnetic waves is shown. It is explanatory drawing which shows the generation | occurrence | production waveform which synthesize | combined the conjugate waveform and basic waveform of the reflected wave waveform in the electromagnetic wave oscillation apparatus. It is explanatory drawing explaining the outline of the control method of the electromagnetic wave oscillation apparatus of this invention, (a) is a Smith chart which shows each impedance of an oscillator, a line | wire, and a resistance part, (b) is each of an oscillator, a line | wire, and a resistance part. It is a flowchart which shows an impedance. It is the schematic of the electromagnetic wave oscillation apparatus of the 2nd invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following embodiments are essentially preferable examples, and are not intended to limit the scope of the present invention, its application, or its use.

<Embodiment 1>
The first embodiment is an electromagnetic wave oscillation device 1 including a booster circuit according to the first invention. As shown in FIG. 1, the electromagnetic wave oscillation device 1 includes an electromagnetic wave oscillator 3 that oscillates an electromagnetic wave by a voltage applied from a power supply P, a resistance unit 2 that receives supply of electromagnetic wave energy from the electromagnetic wave oscillator 3, and this resistance A detector 4 that detects the phase and amplitude of the reflected wave from the unit 2, and a controller 5 that controls the electromagnetic wave oscillator 3 and the detector 4 are provided. Then, a modulator 31 that modulates the phase and amplitude of the electromagnetic wave from the electromagnetic wave oscillator 3 and an amplifier 32 that amplifies the electromagnetic wave are disposed between the electromagnetic wave oscillator 3 and the detector 4. With respect to the phase and amplitude of the detected reflected wave waveform, the modulator 31 is set so that a waveform having a phase and amplitude taking a conjugate value is added to (combined with) the basic waveform oscillated by the electromagnetic wave oscillator 3 to be a generated waveform. I try to control it.

The detector 4 is not particularly limited as long as it can detect the phase and amplitude of the reflected wave from the resistance unit 2, but in this embodiment, the detector 4 and the 4-port directional coupler 41 The IQ demodulator 42 attached to the traveling wave extraction port and the IQ demodulator 43 attached to the reflected wave extraction port.

And the resistance part 2 of this embodiment is an ignition device which raises the electromagnetic wave supplied by the resonance circuit and raises the potential difference of the discharge gap 2a to cause discharge as shown in the equivalent circuit of FIG. This ignition device can be reduced in outer diameter as compared with a general spark plug, and the intake / exhaust valve of the internal combustion engine can be enlarged, so that the efficiency of the internal combustion engine can be improved. Further, it is possible to improve the combustion efficiency by performing multi-point ignition in which a plurality of cylinder heads are arranged and ignite the air-fuel mixture at a plurality of locations.

The detector 4 may detect the phase / amplitude of the reflected waveform W2 only with the IQ demodulator 43 by setting the line length to a predetermined value, but the IQ demodulator 42 and the IQ demodulator 43 It is preferable that the phase difference between the waveform W1 and the reflected waveform W2 be detected.

Further, as shown in FIG. 2, the resistance portion 2 may be an object to be heated that is irradiated with electromagnetic waves (microwaves) from an electromagnetic wave radiation antenna 7. For example, the resistance portion 2 can be a purification catalyst in which an electromagnetic wave absorber that is heated and heated by receiving electromagnetic waves is mixed. Moreover, the foodstuff etc. which are heated and cooked with an electromagnetic wave heating apparatus (microwave oven etc.) can also be used as the resistance part 2.

The electromagnetic wave oscillated from the electromagnetic wave oscillator 3 is amplified to a predetermined output (an electromagnetic wave of about several W is amplified to several kW) by an amplifier 32 through a modulator 31. In the figure, the amplifier 32 is an example of one stage, but the amplifier 32 may be configured in a multistage configuration in series with two stages and three stages. When three stages are used, for example, the first stage is GAIN control, for example, 0 to 25 dBm (0 to about 398 mW), the second stage is, for example, a preamplifier, for example, 45 dBM (about 32 W), and the third stage is, for example, a main amplifier. , 61 dBM (about 1.25 kW).

The electromagnetic wave oscillator 3 is always supplied with a predetermined voltage, for example, 12 V, from the DC power source P via a smoothing circuit (not shown). When an electromagnetic wave oscillation signal (for example, TTL signal) is received from the control device 5, the electromagnetic wave (microwave) is output in a continuous wave or a pattern in which a predetermined duty ratio, pulse time, and the like are set.

The modulator 31 receives a control signal from the control device 5 to which the phase / amplitude information of the reflected waveform W2 detected by the detector 4 is applied, and modulates the phase and amplitude of the electromagnetic wave oscillated from the electromagnetic wave oscillator 3. More specifically, as shown in FIG. 3, when the reflected waveform W2 reflected from the resistance unit 2 is used with respect to the basic waveform W1, the conjugate waveform W3 of the reflected waveform W2 is vector-added (synthesized) to the basic waveform. The phase and amplitude are modulated so that the generated waveform W0 is obtained. This control is performed in units of microseconds, the reflected waveform W2 is canceled with the generated waveform W0, and the basic waveform W1 is supplied to the resistance unit 2.

4, when the impedance of the electromagnetic wave oscillator 3 is Zs, the impedance of the line is Zo, and the impedance of the resistance unit 2 is Zr (see FIG. 4B), the oscillator 3 corresponds to the impedance Zr of the resistance unit 2. The modulator 32 is controlled so that the impedance becomes Zs ″ having a conjugate value. More specifically, the center of the Smith chart, for example, the amplitude of Z of 50Ω is modulated, and Zs ′ is controlled to be Zs ″ by modulating the phase and then the phase.

This makes it possible to perform an apparent impedance matching viewed from the resistance unit 2, suppress a reflected wave from the resistance unit 2, and improve the efficiency of supplying electromagnetic waves to the resistance unit 2.

<Embodiment 2>
The second embodiment is an electromagnetic wave oscillation device 1 including a booster circuit according to the second invention. As shown in FIG. 5, the electromagnetic wave oscillation device 1 includes an electromagnetic wave oscillator 3 that oscillates an electromagnetic wave by a voltage applied from a power supply P, a resistance unit 2 that receives supply of electromagnetic wave energy from the electromagnetic wave oscillator 3, and this resistance A detector 4 that detects the phase and amplitude of the reflected wave from the unit 2, and a controller 5 that controls the electromagnetic wave oscillator 3 and the detector 4 are provided. Then, the electromagnetic wave from the electromagnetic wave oscillator 3 is branched, and modulators 31a and 31b for modulating the phase and amplitude of the electromagnetic wave and amplifiers 32a and 32b for amplifying the electromagnetic wave are arranged on each line, and the branched line is a coupler. The control unit 5 branches to a phase and amplitude waveform that takes conjugate values with respect to the phase and amplitude of the reflected wave waveform detected by the detector 4. The at least one modulator 31a, 31b is controlled.

The second embodiment is different from the first embodiment in that the electromagnetic waves from the electromagnetic wave oscillator 3 are branched, and modulators 31a and 31b that modulate the phase and amplitude of the electromagnetic waves and amplifiers 32a and 32b that amplify the electromagnetic waves are provided in the respective lines. This is the point of arrangement. The line that generates a waveform having a phase and amplitude that takes a conjugate value with respect to the phase and amplitude of the reflected wave waveform may be any one of the branched lines. In this embodiment, only the modulator 31b is controlled. Then, it is configured to cancel the reflected wave.

By configuring in this way, the basic waveform W1 shown in FIG. 3 is passed through the line of the modulator 31a, and the conjugate waveform W2 is passed through the line of the modulator 31b, via the coupler 33 (for example, a directional coupler), Both waves merge to form a waveform similar to the generated waveform W0 shown in FIG. 3 and cancel the reflected wave.

As a result, as in the first embodiment, it is possible to perform apparent impedance matching as viewed from the resistance unit 2, suppress the reflected wave from the resistance unit 2, and improve the supply efficiency of the electromagnetic wave to the resistance unit 2.

As described above, the electromagnetic wave oscillating device according to the present invention is an ignition device for an internal combustion engine such as an automobile engine, which boosts an electromagnetic wave supplied by a resonance circuit and raises a potential difference of a discharge gap to generate a discharge. It is suitably used for the application of the electromagnetic wave and the electromagnetic wave supply to the antenna of the electromagnetic wave heating device and the catalyst heating / heating device.

DESCRIPTION OF SYMBOLS 1 Electromagnetic oscillation apparatus 2 Resistance part 3 Electromagnetic wave oscillator 31 Modulator 32 Amplifier 4 Detector 5 Control apparatus P Power supply

Claims (2)

An electromagnetic wave oscillation device that supplies an electromagnetic wave to a resistance unit that receives supply of electromagnetic wave energy,
An electromagnetic wave oscillator that oscillates an electromagnetic wave by a voltage applied from a power supply;
A detector for detecting the phase and amplitude of the reflected wave from the resistance unit;
A controller for controlling the electromagnetic wave oscillator and the detector,
A modulator for modulating the phase and amplitude of the electromagnetic wave from the electromagnetic wave oscillator and an amplifier for amplifying the electromagnetic wave are disposed;
The control device controls the modulator so that a waveform having a phase and amplitude taking conjugate values is added to the basic waveform by vector addition to the phase and amplitude of the reflected wave waveform detected by the detector. An electromagnetic wave oscillation device designed to be used. An electromagnetic wave oscillation device that supplies an electromagnetic wave to a resistance unit that receives supply of electromagnetic wave energy,
An electromagnetic wave oscillator that oscillates an electromagnetic wave by a voltage applied from a power supply;
A detector for detecting the phase and amplitude of the reflected wave from the resistance unit;
A controller for controlling the electromagnetic wave oscillator and the detector,
The electromagnetic wave from the electromagnetic wave oscillator is branched, and a modulator that modulates the phase and amplitude of the electromagnetic wave and an amplifier that amplifies the electromagnetic wave are disposed on each line, and the branched line is connected to the resistance unit via a coupler. And
The controller controls at least one of the modulators branched so as to obtain a phase and amplitude waveform that takes a conjugate value with respect to the phase and amplitude of the reflected wave waveform detected by the detector. Electromagnetic wave transmitter.

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