CN116181542A - Coaxial plasma igniter and plasma ignition system - Google Patents

Abstract

The present invention relates to a coaxial plasma igniter. The coaxial plasma igniter comprises: an igniter shell, a ceramic connector, an igniter cathode and an igniter anode; the ceramic connector is coaxially arranged on the ignition Inside the igniter shell, the ceramic connecting piece is provided with a flow channel, one end of the flow channel communicates with the air intake hole provided on the igniter shell, and the other end of the flow channel is aligned with the ceramic connecting piece and the The igniter discharge area between the igniter shells; the igniter cathode is coaxially arranged in the central hole of the ceramic connector; the igniter anode is coaxially arranged at one end of the igniter shell. The invention can organize the plasma in the plasma generator through the coaxial structure plasma generator with the igniter cathode and igniter anode coaxially arranged, so that the generation of plasma is not affected by the high-speed incoming flow environment in the engine, and realizes Ignition under extreme conditions.

Description

A coaxial plasma igniter and plasma ignition system

technical field

The invention relates to the technical field of engine device research, in particular to a coaxial plasma igniter and a plasma ignition system.

Background technique

With the development of the arms race, in order to improve the anti-reconnaissance and anti-interception capabilities of aircraft, aircraft powered by aero-engines and ramjet engines are gradually moving towards near space. Engines flying at high altitude, high speed, low pressure, and low temperature have very bad working conditions in the combustion chamber, which is prone to problems such as poor combustion stability, reduced combustion efficiency, and even failure to ignite after blowing out. The essence of flame stability in the engine is the matching of flame propagation velocity and incoming gas velocity. During ignition, the engine is in a cold state and requires a large amount of energy injection to successfully ignite the engine; while in stable combustion, the temperature inside the engine is high. Only a small amount of energy is required to achieve flame stabilization. In view of the different requirements of ignition and stable combustion, it is urgent to develop a device capable of high-power ignition under extreme conditions.

Contents of the invention

The purpose of the present invention is to provide a coaxial plasma igniter and a plasma ignition system to realize ignition under extreme conditions and overcome the technical defect that existing aircraft cannot be ignited after being turned off.

To achieve the above object, the present invention provides the following scheme:

The present invention provides a coaxial plasma igniter. The coaxial plasma igniter includes: an igniter shell, a ceramic connector, an igniter cathode, and an igniter anode;

The ceramic connecting piece is arranged coaxially inside the igniter casing, and a flow passage is provided on the ceramic connecting piece, and one end of the flow passage communicates with an air inlet provided on the igniter casing, and the flow passage The other end of the track is aligned with the igniter discharge area between the ceramic connector and the igniter housing;

The igniter cathode is coaxially arranged in the central hole of the ceramic connector;

The igniter anode is coaxially arranged at one end of the igniter casing.

Optionally, the igniter casing is a cylindrical structure.

Optionally, the ceramic connector is a cylindrical column structure with a central hole.

Optionally, the igniter cathode is a cylindrical structure.

Optionally, the anode of the igniter is a cap-shaped structure.

Optionally, the igniter anode and the igniter casing can be an integrated structure.

Optionally, the coaxial discharge gap between the igniter cathode and the igniter anode is 0.1-5mm.

A plasma ignition system, the ignition system comprising: a coaxial plasma igniter, a working medium gas supply device and a multi-mode plasma power supply;

The working medium gas supply device is connected to the air inlet provided on the igniter casing of the coaxial plasma igniter through a gas path, and the multi-mode plasma power supply is connected to the coaxial plasma igniter.

Optionally, the multi-mode plasma power supply includes an arc plasma power supply and a high-frequency pulse plasma power supply;

The high-level output terminal of the arc plasma power supply is connected to one end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply; the ground level output terminal of the arc plasma power supply is connected to the coaxial plasma igniter one end of the connection;

The other end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply is connected to the other end of the coaxial plasma igniter.

Optionally, a coupling circuit is also provided between the arc plasma power supply and the high-frequency pulse plasma power supply;

The coupling circuit includes an inductor L1, an inductor L2, and a capacitor C1;

One end of the inductor L1 is connected to the high-level output end of the arc plasma power supply;

The other end of the inductor L1 is connected to one end of the inductor L2 and one end of the capacitor C1;

The other end of the inductance L2 is connected to one end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply;

The other end of the capacitor C1 is connected to the ground level output end of the arc plasma power supply.

Optionally, the number of the high-frequency pulsed plasma power supply is one or more.

Optionally, the high-frequency pulsed plasma power supply includes a second AC source, an input transformer, an output transformer, an arc spark plug, and a capacitor;

Both ends of the second AC source are connected to the primary side of the input transformer;

One end of the secondary side of the input transformer is connected to one end of the arc spark plug and one end of the capacitor;

The other end of the secondary side of the input transformer is connected to the other end of the arc spark plug and one end of the primary side of the output transformer;

The other end of the capacitor is connected to the other end of the primary side of the output transformer.

Optionally, the arc plasma power supply is used for the ignition system to provide power for the coaxial plasma igniter in the thermal plasma working mode. When the arc plasma power supply is a DC excitation source, the output of the arc plasma power supply The voltage range is: 100-500V, and the current range output by the arc plasma power supply is: 10-100A; when the arc plasma power supply is an AC excitation source, the output voltage range of the arc plasma power supply is: 1000-50000V , the output current range of the arc plasma power supply is: 50mA-50A, and the output frequency range of the arc plasma power supply is 50Hz-100kHz.

Optionally, the high-frequency pulsed plasma power supply is used for the ignition system to provide power for the coaxial plasma igniter in the cool plasma working mode, and the output voltage range, output current range, Frequency range, pulse width range and pulse rise time range are: 0-100kV, 0-300A, 10-100kHz, 10-1000ns and 1-10ns respectively.

According to the specific embodiments provided by the invention, the invention discloses the following technical effects:

The invention discloses a coaxial plasma igniter. The coaxial plasma igniter comprises: an igniter shell, a ceramic connector, an igniter cathode and an igniter anode; the ceramic connector is coaxially arranged on the Inside the igniter shell, the ceramic connector is provided with a flow channel, one end of the flow channel communicates with the air intake hole provided on the igniter shell, and the other end of the flow channel is aligned with the ceramic connector and The igniter discharge area between the igniter shells; the igniter cathode is coaxially arranged in the central hole of the ceramic connector; the igniter anode is coaxially arranged at one end of the igniter shell. The invention can organize the plasma in the plasma generator through the coaxial structure plasma generator with the igniter cathode and igniter anode coaxially arranged, so that the generation of plasma is not affected by the high-speed incoming flow environment in the engine, and realizes Ignition under extreme conditions.

The present invention also provides a plasma ignition system, which provides multiple power sources through a multi-mode plasma power source, realizes outputting different plasma power sources during ignition and stable combustion, and realizes the use of plasma with high temperature and high density of active particles during ignition , improve the success rate of ignition; in the stable combustion, the plasma with high active particle density is used to realize the stable combustion with low power, not only can ignite with high power under extreme conditions, but also can use an igniter with lower power to stabilize the flame in the combustion chamber , in order to improve the reliability of starting ignition and broaden the stable working range.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required in the embodiments. Obviously, the accompanying drawings in the following description are only some of the present invention. Embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without paying creative labor.

Fig. 1 is the structural diagram of a kind of coaxial plasma igniter provided by the present invention;

Fig. 2 is a structural composition diagram of the multi-mode plasma power supply provided by the present invention;

Fig. 3 is a structural composition diagram of another multi-mode plasma power supply provided by the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The purpose of the present invention is to provide a coaxial plasma igniter and a plasma ignition system to realize ignition under extreme conditions and overcome the technical defect that existing aircraft cannot be ignited after being turned off.

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1, the embodiment of the present invention provides a coaxial plasma igniter, which includes: an igniter housing 1, a ceramic connector 2, and an igniter cathode 3 (for example, an igniter The cathode 3 includes an igniter cathode rod and an igniter cathode end) and an igniter anode 4; the ceramic connector 2 is coaxially arranged inside the igniter housing 1, and the ceramic connector is coaxially arranged on the igniter Inside the igniter housing, the ceramic connector 2 is provided with a flow channel 5, one end of the flow channel 5 communicates with the air intake hole provided on the igniter housing 1, and the other end of the flow channel 5 is aligned with the The igniter discharge area between the ceramic connector 2 and the igniter housing 1; the igniter cathode 3 is coaxially arranged in the central hole of the ceramic connector 2; the igniter anode 4 is coaxially arranged in the One end of the igniter housing 1 . Specifically, the igniter anode 4 is installed on the igniter casing 1 through threads.

As a preferred embodiment, as shown in FIG. 1 , a reflux device 6 is provided outside the igniter casing 1 , and the reflux device 6 is screwed to the igniter casing 1 .

The igniter casing 1 is a cylindrical structure.

The other end of the igniter housing 1 (the left side in Fig. 1 ) is connected with the combustion chamber of the engine (the connection mode is threaded connection), the center of the igniter housing 1 is used for installing the ceramic connector 2, and one end of the igniter housing 1 ( The right side in Figure 1) installs the generator anode (the installation method is threaded connection), and achieves axial positioning with the igniter anode 4 through the rightmost end face.

The ceramic connector 2 is a cylindrical column structure with a central hole. The extension on the left side of the ceramic connector 2 is used to ensure that no surface discharge occurs between the igniter cathode and the igniter shell, and the central hole is used to install the igniter. The cathode and the flow channel are used for the working gas to flow into the discharge area of the igniter. The pressure of the working medium gas is 0.01-3.0MPa, and the type of the working medium gas is air, oxygen or nitrogen.

The igniter cathode 3 is a cylindrical structure, and the igniter anode 4 is a cap-shaped structure.

The coaxial discharge gap between the igniter cathode 3 and the igniter anode 4 is 0.1-5mm.

In the discharge area between the igniter cathode 3 and the igniter anode 4 there is also provided an axial fixation device 7 for the igniter cathode 3 . The axial fixing device 7 is a U-shaped structure, and the opening of the U-shaped structure is opposite to the central hole of the ceramic connector and connected to the right end of the ceramic connector 2 . The material of the axial fixing device 7 is copper, and it not only serves to limit the axial movement of the cathode 3 of the igniter, but also has a discharge function.

The present invention also provides a plasma ignition system, which includes: a coaxial plasma igniter, a working medium gas supply device and a multi-mode plasma power supply; the working medium gas supply device is connected to the The gas inlet hole on the igniter shell of the coaxial plasma igniter is connected, and the multi-mode plasma power supply is connected with the coaxial plasma igniter.

The working medium gas supply device provides the working medium gas for the coaxial plasma igniter through the gas path connection. When the multi-mode plasma power supply is working, an electric field is formed between the cathode and the anode of the coaxial plasma igniter to discharge the working medium gas Plasma flow is generated by breakdown; the plasma power supply is formed by a combination of DC plasma power supply and high-frequency pulse plasma power supply, which can be freely switched between two different working modes through the power selector, that is, multi-mode working mode.

As an implementation, that is, as shown in Figure 2, when the arc plasma power supply is DC excitation, the power supply is a DC plasma power supply, and at this time the multi-mode plasma power supply includes a DC plasma power supply, a high-frequency pulse Plasma power supply; the high-level output terminal of the DC plasma power supply is connected to one end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply, and the ground level output terminal of the DC plasma power supply is connected to one end of the coaxial plasma igniter The other end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply is connected to the other end of the coaxial plasma igniter. Exemplarily, one end of the coaxial plasma igniter is the anode or cathode of the coaxial plasma igniter, and one end of the corresponding coaxial plasma igniter is the cathode or anode of the coaxial plasma igniter. As a preferred embodiment, one end of the coaxial plasma igniter is the igniter anode of the coaxial plasma igniter, and one end of the coaxial plasma igniter is the igniter cathode of the coaxial plasma igniter.

As another implementation, as shown in Figure 3, when the arc plasma power supply is AC excitation, the power supply is an AC plasma power supply, and at this time the multi-mode plasma power supply includes an AC plasma power supply, a high-frequency pulse plasma Body power supply; the high-level output end of the AC plasma power supply is connected to one end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply, and the ground level output end of the AC plasma power supply is connected to one end of the coaxial plasma igniter , the other end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply is connected with the other end of the coaxial plasma igniter. Exemplarily, one end of the coaxial plasma igniter is the anode or cathode of the coaxial plasma igniter, and one end of the corresponding coaxial plasma igniter is the cathode or anode of the coaxial plasma igniter. As a preferred embodiment, one end of the coaxial plasma igniter is the igniter anode of the coaxial plasma igniter, and one end of the coaxial plasma igniter is the igniter cathode of the coaxial plasma igniter.

The DC plasma power supply includes a first AC source, a first rectifier, an inverter and a second rectifier connected in sequence. A filter circuit is arranged between the first rectifier and the inverter. Exemplarily, the first AC source is commercial power (the commercial power is the position of the AC source in FIG. 2 ).

The AC plasma power supply includes a first AC source, a first rectifier and an inverter connected in sequence. A filter circuit is arranged between the first rectifier and the inverter. Exemplarily, the first AC source is commercial power.

The plasma ignition system of the present invention can also realize the function of a multi-frequency plasma igniter by coupling an arc plasma power supply with one or more high-frequency pulse plasma power supplies.

The present invention selects according to needs, and realizes that only the arc plasma power supply works, only the high-frequency pulse plasma power supply works, or two plasma power supplies cooperate; the plasma power supply (arc light plasma power supply and high-frequency pulse plasma power supply) body power supply) can control the power of the input igniter by adjusting the output parameters; the output parameters of the arc plasma power supply include voltage and current; the output parameters of the high-frequency pulse plasma power supply include voltage, current, frequency , pulse width and pulse rise time.

The multi-mode working mode includes a hot plasma mode and a cold plasma mode; the hot plasma mode is a mode in which the plasma power supply is independently operated by an arc plasma power supply; the cold plasma mode is a plasma power supply A mode that is operated solely by a high-frequency pulsed plasma power supply.

The arc plasma power supply (DC plasma power supply or AC plasma power supply) is used for the ignition system to provide power for the coaxial plasma igniter in the thermal plasma working mode, and the output voltage range of the DC plasma power supply is: 100-500V, the current range output by the DC plasma power supply is: 10-100A; the voltage range output by the AC plasma power supply is: 1000-50000V; the current range output by the AC plasma power supply is: 50mA- 50A, the frequency range of the AC plasma power output is 50Hz-100kHz, it can input high-power energy, and it is mainly manifested as thermal effect, which is used to ensure the high temperature environment necessary for ignition, which is conducive to improving the ignition reliability under harsh working conditions .

The arc plasma power supply is used for the ignition system to provide power for the coaxial plasma igniter in the thermal plasma working mode. The power supply can choose DC plasma power supply or AC plasma power supply. When the arc plasma power supply selects DC plasma power supply, the output current range of the coaxial plasma igniter is 10-100A; when the arc plasma power supply selects AC arc plasma power supply, the coaxial plasma igniter The output current range is 0-100kV.

The high-frequency pulsed plasma power supply is used for the ignition system to provide power for the coaxial plasma igniter in the cold plasma working mode, and the voltage range, current range, frequency range, pulse width range and pulse rise time range are respectively: 0 -100kV, 0-300A, 10-100kHz, 10-1000ns and 1-100ns can realize the generation of many active groups used to increase the reaction speed and accelerate the rate of combustion reaction under the condition of less energy input. When the energy is low, the ignition energy threshold can be lowered to facilitate ignition; this mode can continue to work after the ignition is completed, which is used to improve the combustion efficiency and improve the economy of the engine.

The high-frequency pulsed plasma power supply includes a second AC source (example is commercial power, the AC source in Figures 2 and 3), an input transformer, an arc spark plug, an output transformer and a capacitor, and the second AC source The voltage is first boosted by the input transformer, loaded on the arc spark plug, and charges the capacitor at the same time. After the voltage exceeds the breakdown voltage of the arc spark plug, the spark plug breaks down and becomes a path, and the capacitor discharges to the spark plug and outputs through the output transformer. into the coaxial plasma igniter.

Coupling circuit C includes inductance L1, inductance L2 and capacitor C2. Inductor L1 is connected to the output end of the arc plasma source to play the role of separating pulses from DC. Inductor L2 plays the role of voltage division to protect the DC arc plasma source. Capacitor C1 acts as a DC-blocking pulse and provides a path for the pulse output.

The ignition system of the present invention can switch between various working modes according to actual needs without changing the structure of the igniter and power supply, which not only ensures the reliability of ignition, but also improves the economy of the engine.

According to the specific embodiments provided by the invention, the invention discloses the following technical effects:

The invention discloses a coaxial plasma igniter. The coaxial plasma igniter comprises: an igniter shell, a ceramic connector, an igniter cathode and an igniter anode; the ceramic connector is coaxially arranged on the Inside the igniter shell, the ceramic connector is provided with a flow channel, one end of the flow channel communicates with the air intake hole provided on the igniter shell, and the other end of the flow channel is aligned with the ceramic connector and The igniter discharge area between the igniter shells; the igniter cathode is coaxially arranged in the central hole of the ceramic connector; the igniter anode is coaxially arranged at one end of the igniter shell. The invention can organize the plasma in the plasma generator through the coaxial structure plasma generator with the igniter cathode and igniter anode coaxially arranged, so that the generation of plasma is not affected by the high-speed incoming flow environment in the engine, and realizes Ignition under extreme conditions.

The present invention also provides a plasma ignition system, which provides multiple power sources through a multi-mode plasma power source, realizes outputting different plasma power sources during ignition and stable combustion, and realizes the use of plasma with high temperature and high density of active particles during ignition , improve the success rate of ignition; in the stable combustion, the plasma with high active particle density is used to realize the stable combustion with low power, not only can ignite with high power under extreme conditions, but also can use an igniter with lower power to stabilize the flame in the combustion chamber , in order to improve the reliability of starting ignition and broaden the stable working range.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other.

In this paper, specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea; meanwhile, for those of ordinary skill in the art, according to the present invention Thoughts, there will be changes in specific implementation methods and application ranges. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims (11)

1. A coaxial plasma igniter is characterized in that the coaxial plasma igniter comprises: igniter shell, ceramic connector, igniter cathode and igniter anode; The ceramic connecting piece is arranged coaxially inside the igniter casing, and a flow passage is provided on the ceramic connecting piece, and one end of the flow passage communicates with an air inlet provided on the igniter casing, and the flow passage The other end of the track is aligned with the igniter discharge area between the ceramic connector and the igniter housing; The igniter cathode is coaxially arranged in the central hole of the ceramic connector; The igniter anode is coaxially arranged at one end of the igniter casing. 2. The coaxial plasma igniter according to claim 1, characterized in that, the outer shell of the igniter is a cylindrical structure. 3. The coaxial plasma igniter according to claim 1, characterized in that, the ceramic connecting piece is a cylindrical column structure with a central hole. 4. The coaxial plasma igniter according to claim 1, wherein the cathode of the igniter is a cylindrical structure. 5. The coaxial plasma igniter according to claim 1, characterized in that, the igniter anode is a cap-shaped structure. 6. The coaxial plasma igniter according to claim 1, characterized in that, the coaxial discharge gap between the igniter cathode and the igniter anode is 0.1-5 mm. 7. A plasma ignition system, characterized in that the ignition system comprises: the coaxial plasma igniter according to any one of claims 1-6, a working gas supply device and a multi-mode plasma power supply; The working medium gas supply device is connected to the air inlet provided on the igniter casing of the coaxial plasma igniter through a gas path, and the multi-mode plasma power supply is connected to the coaxial plasma igniter. 8. The plasma ignition system according to claim 7, wherein the multi-mode plasma power supply comprises an arc plasma power supply and a high-frequency pulse plasma power supply; The high-level output terminal of the arc plasma power supply is connected to one end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply; the ground level output terminal of the arc plasma power supply is connected to the coaxial plasma igniter one end of the connection; The other end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply is connected to the other end of the coaxial plasma igniter. 9. The plasma ignition system according to claim 8, wherein a coupling circuit is further provided between the arc plasma power supply and the high-frequency pulse plasma power supply; The coupling circuit includes an inductor L1, an inductor L2, and a capacitor C1; One end of the inductor L1 is connected to the high-level output end of the arc plasma power supply; The other end of the inductor L1 is connected to one end of the inductor L2 and one end of the capacitor C1; The other end of the inductance L2 is connected to one end of the secondary coil of the output transformer of the high-frequency pulse plasma power supply; The other end of the capacitor C1 is connected to the ground level output end of the arc plasma power supply. 10. The plasma ignition system according to claim 9, characterized in that the number of the high-frequency pulsed plasma power supply is one or more. 11. The plasma ignition system according to claim 8, wherein the high-frequency pulse plasma power supply comprises a second AC source, an input transformer, an output transformer, an arc spark plug, and a capacitor; Both ends of the second AC source are connected to the primary side of the input transformer; One end of the secondary side of the input transformer is connected to one end of the arc spark plug and one end of the capacitor; The other end of the secondary side of the input transformer is connected to the other end of the arc spark plug and one end of the primary side of the output transformer; The other end of the capacitor is connected to the other end of the primary side of the output transformer.

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