Ignition electrode and ignition system for a retractable heavy-duty gas turbine with pneumatic structure

Abstract

The application discloses a telescopic heavy gas turbine ignition electrode with a pneumatic structure and an ignition system. The ignition electrode comprises a cylinder cavity, the cylinder cavity comprises oppositely arranged end covers and a mounting flange, and a through hole is formed in the mounting flange; a piston is slidably arranged along the inner side wall of the cylinder cavity; a reset spring is arranged between the piston and the mounting flange; an ignition rod is telescopically arranged through the end cover into the cylinder cavity and is fixedly connected with the piston, and the ignition rod enters the through hole; wherein the mounting flange is provided with a mounting flange air inlet channel, a mounting flange gas collecting ring cavity and a sealing air channel which are sequentially communicated, the sealing air channel is communicated with the through hole, and high-pressure air discharged from the sealing air channel is adapted to be downwardly sprayed to the gap between the through hole and the ignition rod. The high-pressure air downwardly sprayed from the sealing air channel can block the ring cavity air and high-temperature gas from entering the ignition electrode.

Description

Technical Field

[0001] This invention relates to the field of heavy-duty gas turbine ignition nozzle technology, specifically to a retractable heavy-duty gas turbine ignition nozzle with a pneumatic structure and an ignition system. Background Technology

[0002] Heavy-duty gas turbine power generation technology plays an important role in grid peak shaving and the "dual carbon" strategy due to its advantages such as fast start-up speed, strong fuel adaptability, high combustion efficiency, low pollutant emissions, compact structure, and ease of peak shaving.

[0003] The combustion chamber, as a core component of a gas turbine, primarily functions to convert the chemical energy of fuel into the thermal and potential energy of the combustion gas. The expanded combustion gas then drives the turbine to perform work. During gas turbine operation, the reliability of combustion chamber ignition is a crucial technical indicator, a prerequisite for the normal operation of the entire system. Furthermore, heavy-duty gas turbines require frequent start-ups and shutdowns during grid peak shaving, placing even higher demands on the stability and reliability of the ignition system.

[0004] To avoid the impact of the high temperature and high pressure environment in the combustion chamber on the lifespan of the ignition nozzle, retractable ignition nozzles are often used in heavy-duty gas turbines.

[0005] There has been much research on retractable ignition nozzles both domestically and internationally. One existing retractable ignition device suitable for heavy-duty gas turbines works on the following principle: during ignition, the ignition rod of the nozzle is pushed into the combustion chamber by the spring force. After successful ignition, the ignition rod is pulled out of the combustion chamber by the pressure difference between the inside and outside of the combustion chamber or by compressed air. However, in this type of retractable ignition nozzle, the spring in the nozzle is always in a compressed state when the nozzle is not ignited. Over time, this will affect the spring force, causing the speed at which the spring pulls the ignition rod out of the combustion chamber to slow down, increasing the risk of the ignition rod being burned.

[0006] To overcome the problem that the spring is always in a compressed state when not ignited, affecting the spring force, another type of retractable ignition nozzle has emerged. Its principle is as follows: during ignition, compressed air pushes the piston to move. The piston drives the ignition rod, which is fixedly connected to it, to continue to extend out of the through hole at the bottom of the cylinder and into the combustion chamber for ignition. At the same time, the spring that is against the piston is compressed. After successful ignition, the air pressure above the piston is reduced, and the spring will rebound, which can push the piston back to its original position. During the piston's return to its original position, the ignition rod is driven out of the combustion chamber.

[0007] However, this type of retractable ignition nozzle still has shortcomings:

[0008] After the ignition succeeds, the ignition rod exits the combustion chamber, but the high-temperature gas and the annular cavity air are easy to enter the ignition electrode from the gap between the ignition rod and the through hole, and the high-temperature gas and the annular cavity air affect the elasticity of the spring, and then affect the speed of the spring driving the ignition electrode to exit the combustion chamber, and increase the risk of ablation of the ignition rod.

[0009] In view of the deficiencies in the prior art, it is necessary to design a telescopic heavy gas turbine ignition electrode with a pneumatic structure and an ignition system. SUMMARY

[0010] Therefore, the technical problem to be solved by the present application is that the high-temperature gas and the annular cavity air entering the ignition electrode from the gap between the ignition rod and the through hole affect the elasticity of the spring, thereby providing a telescopic heavy gas turbine ignition electrode with a pneumatic structure and an ignition system.

[0011] To solve the above technical problems, the technical scheme of the present application is as follows:

[0012] A telescopic heavy gas turbine ignition electrode with a pneumatic structure, the ignition electrode comprising:

[0013] A cylinder cavity comprising oppositely arranged end covers and a mounting flange, the mounting flange being provided with a through hole;

[0014] A piston slidingly arranged along the inner side wall of the cylinder cavity;

[0015] A return spring arranged between the piston and the mounting flange;

[0016] An ignition rod telescopically penetrating the end cover into the cylinder cavity and fixedly connected with the piston, the ignition rod penetrating the through hole; wherein,

[0017] The mounting flange is provided with a mounting flange air inlet channel, a mounting flange gas collecting ring cavity and a sealing air channel which are sequentially communicated, the sealing air channel being communicated with the through hole, and the high-pressure air from the sealing air channel being adapted to be downwardly sprayed to the gap between the through hole and the ignition rod.

[0018] Further, the sealing air channel is continuously arranged around the through hole.

[0019] Further, the height of the sealing air channel is 1mm-3mm, and / or the sealing air channel extends downwardly at an angle of 15°-45° with the central axis of the ignition rod.

[0020] Furthermore, the piston has a piston conical sealing surface at one end facing the mounting flange, and the through hole has a mounting flange conical sealing surface at one end facing the piston. In the ignition state of the ignition nozzle, the piston conical sealing surface and the mounting flange conical sealing surface are in close contact.

[0021] Furthermore, the mounting flange tapered sealing surface is continuously arranged around the through hole, and / or the piston tapered sealing surface is continuously arranged around the ignition rod.

[0022] Furthermore, three piston rings are sequentially installed on the outer cylinder wall of the piston, with the openings of the three piston rings staggered by 180°.

[0023] Furthermore, the end cover is provided with an end cover air inlet channel, an end cover air collecting ring cavity and a high-pressure air nozzle connected in sequence, and the high-pressure air nozzle is connected to the cylinder cavity.

[0024] Furthermore, the high-pressure air nozzles are arranged at intervals along the circumference of the ignition rod, and / or the diameter of the high-pressure air nozzles is 3mm-6mm.

[0025] The technical solution of this invention has the following advantages:

[0026] 1. The present invention provides a retractable heavy-duty gas turbine ignition nozzle with a pneumatic structure. The cylinder cavity includes an end cover and a mounting flange arranged opposite each other. A through hole is provided on the mounting flange. The ignition rod extends and retracts through the end cover into the cylinder cavity and is fixedly connected to the piston. The ignition rod enters the through hole. The mounting flange has a mounting flange air inlet channel, a mounting flange gas collecting ring cavity, and a sealing air channel connected in sequence. The sealing air channel is connected to the through hole. After ignition, during the piston's return to its original position under the elastic restoring force of the return spring, it will drive the fixedly connected ignition rod back to its original position. The ignition rod retracts from the combustion chamber. At this time, high-pressure air is introduced into the air intake channel of the mounting flange, and then sequentially enters the gas collecting ring cavity and the sealing air channel of the mounting flange. Since the sealing air channel is connected to the through hole, the high-pressure air ejected from the sealing air channel is sprayed downwards into the gap between the ignition rod and the through hole, forming a blocking airflow to prevent the air in the ring cavity and the high-temperature gas from entering the ignition nozzle. This reduces the impact of the air in the ring cavity and the high-temperature gas on the elasticity of the return spring, ensures the speed at which the ignition rod retracts from the combustion chamber, and thus reduces the risk of the ignition rod of the electric spark nozzle being burned, extending the service life of the ignition nozzle.

[0027] 2. The retractable heavy-duty gas turbine ignition nozzle with pneumatic structure provided by the present invention has a piston conical sealing surface at the end of the piston facing the mounting flange, and a mounting flange conical sealing surface at the end of the through hole facing the piston. In the ignition state of the ignition nozzle, the piston conical sealing surface and the mounting flange conical sealing surface are tightly fitted together. In this way, when the ignition rod is extended, the tight fit between the piston conical sealing surface and the mounting flange conical sealing surface can prevent the annular cavity air and high-temperature gas from entering the ignition nozzle. Combined with the high-pressure air ejected from the sealed air passage on the mounting flange, the annular cavity air and high-temperature gas are prevented from entering the ignition nozzle through the gap between the ignition rod and the through hole. Thus, the ignition nozzle has the ability to prevent the annular cavity air and high-temperature gas from entering the ignition nozzle whether the ignition rod is in the retracted or extended state.

[0028] 3. The retractable heavy-duty gas turbine ignition nozzle with pneumatic structure provided by the present invention has three piston rings installed sequentially on the outer cylinder wall of the piston. The openings of the three piston rings are staggered by 180° to avoid air leakage when the piston moves and to ensure that the ignition rod can quickly and reliably extend into the combustion chamber.

[0029] A retractable heavy-duty gas turbine ignition system with a pneumatic structure, the ignition system comprising:

[0030] The aforementioned retractable heavy-duty gas turbine ignition nozzle with a pneumatic structure;

[0031] air pump;

[0032] A reversing control valve is connected to the air pump via a pipeline;

[0033] The energy storage device is electrically connected to the ignition rod;

[0034] The mounting flange high-pressure air inlet pipe is connected at one end to the reversing control valve and at the other end to the mounting flange air inlet channel.

[0035] The control device is electrically connected to both the reversing control valve and the energy storage device; wherein,

[0036] The control device is adapted to control the reversing control valve to open the inflation path from the air pump to the high-pressure air inlet pipe of the mounting flange according to the stop ignition signal.

[0037] Furthermore, it also includes:

[0038] The high-pressure air inlet pipe of the end cap is connected at one end to the reversing control valve and at the other end to the end cap air inlet channel; wherein,

[0039] The control device is adapted to control the commutating control valve to open the air charging path from the air pump to the end cover high pressure intake pipe according to the ignition signal, and control the energy storage device to energize the ignition rod; the control device is also adapted to control the commutating control valve to close the air charging path from the air pump to the end cover high pressure intake pipe according to the stop ignition signal, and open the exhaust path from the end cover high pressure intake pipe via the commutating control valve.

[0040] The technical scheme of the present application has the following advantages:

[0041] 1. The present application provides a telescopic heavy-duty gas turbine ignition system with a pneumatic structure, which has all the advantages of the aforementioned ignition electrode. BRIEF DESCRIPTION OF DRAWINGS

[0042] In order to more clearly illustrate the specific embodiments of the present application or the technical scheme in the prior art, the following will briefly introduce the drawings needed to be used in the specific embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0043] Figure 1 is a sectional view of the ignition electrode in the present application when the ignition rod is in the retracted state;

[0044] Figure 2 is a sectional view of the ignition electrode in the present application when the ignition rod is in the extended state;

[0045] Figure 3 is a sectional view of the end cover in the present application;

[0046] Figure 4 is a sectional view of the mounting flange in the present application;

[0047] Figure 5 is a schematic view of the telescopic heavy-duty gas turbine ignition system with a pneumatic structure in the present application.

[0048] BRIEF DESCRIPTION OF DRAWINGS

[0049] 1, ignition rod; 2, ignition positive electrode; 3, ignition rod shell; 4, insulating ceramic tube; 5, ignition rod positive electrode joint; 6, ignition cable mounting thread; 7, end cover; 71, insertion hole; 8, sealing ring; 9, bolt; 10, cylinder; 11, piston; 12, return spring; 345, piston ring; 13, first-stage piston ring; 14, second-stage piston ring; 15, third-stage piston ring; 16, mounting flange; 161, via hole; 17, piston conical sealing surface; 18, cylinder cavity; 19, end cover high-pressure intake pipe; 20, end cover intake passage; 21, end cover gas collection ring cavity; 22, high-pressure air injection hole; 23, end cover sealing groove; 24, mounting flange conical sealing surface; 25, mounting flange high-pressure intake pipe; 26, mounting flange intake passage; 27, mounting flange gas collection ring cavity; 28, sealing air passage; 29, mounting flange sealing groove; 30, air pump; 31, pressure regulating valve; 32, reversing control valve; 33, control device; 34, energy storage device; 35, ignition electrode; a, ring cavity air passage; b, fuel gas passage; c, flame tube wall. DETAILED DESCRIPTION

[0050] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0051] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0052] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0053] In addition, the technical features involved in the different embodiments of the application described below can be combined with each other as long as they do not conflict with each other.

[0054] Embodiment 1

[0055] As Figures 1 to 5 shown, the embodiment provides a retractable heavy-duty gas turbine igniter with pneumatic structure.

[0056] In Figure 1 a perspective view, the igniter 35 is fixed to the side wall of the annular cavity air passage a, and below the annular cavity air passage a is the gas passage b. In this embodiment, the igniter 35 includes a cylinder cavity 18, a piston 11, an ignition rod 1, and a return spring 12.

[0057] The ignition rod 1 has a retracted state and an extended state. In the retracted state, the ignition end of the ignition rod 1 is located outside the gas passage b, but the ignition rod 1 enters the annular cavity air passage a and continues to extend downward into the through hole on the flame tube wall c, as shown in Figure 1 . In the extended state, as shown in Figure 2 , the ignition end of the ignition rod 1 extends into the gas passage b.

[0058] The ignition rod 1 includes an ignition anode 2, an ignition rod shell 3, and an insulating ceramic tube 4. The ignition rod shell 3 serves as a negative electrode. The insulating ceramic tube 4 separates the ignition anode 2 and the ignition rod shell 3 to prevent short circuit between them. The upper end of the ignition anode 2 is designed with an ignition rod anode connector 5, and the ignition rod anode connector 5 and the ignition rod shell 3 are connected to a high-voltage power supply through an ignition cable. The upper end of the ignition rod shell 3 is arranged with an ignition cable mounting thread 6 to ensure good contact between the ignition cable and the ignition rod 1 and improve the spark energy of the ignition end. Both the ignition anode 2 and the ignition rod shell 3 are made of high-temperature resistant alloy materials.

[0059] The cylinder cavity 18 is hollow, including the cylinder 10, and the end cover 7 and the mounting flange 16 sealing the opposite ends of the cylinder 10. The end cover 7 and the mounting flange 16 are fastened together by bolts 9. In order to improve the sealing connection performance of the top end of the cylinder 10 and the end cover 7, the end cover sealing groove 23 is provided on the end cover 7, and the top end of the cylinder 10 is sealingly connected with the end cover sealing groove 23. Similarly, in order to improve the sealing connection performance of the bottom end of the cylinder 10 and the mounting flange 16, the mounting flange sealing groove 29 is provided on the mounting flange 16, and the bottom end of the cylinder 10 is sealingly connected with the mounting flange sealing groove 29. The end cover 7 is also provided with a plug-in hole 71. The mounting flange 16 is provided with a through hole 161. The ignition rod 1 can be telescoped into the cylinder cavity 18 from the plug-in hole 71 of the end cover 7 and is fixedly connected with the piston 11. The ignition end of the ignition rod 1 extends out of the through hole 161 and enters the annular cavity air passage a. In order to seal the gap between the end cover 7 and the ignition rod 1, the sealing ring 8 is installed on the end cover 7.

[0060] The end cover 7 is also provided with the end cover air inlet passage 20, the end cover gas collecting annular cavity 21 and the high-pressure air injection hole 22 which are sequentially communicated. In this embodiment, the end cover air inlet passage 20 is communicated with the end cover high-pressure air inlet pipe 19 at the end away from the high-pressure air injection hole 22. The high-pressure air injection hole 22 is vertically downwardly communicated with the cylinder cavity 18, and of course, the high-pressure air injection hole 22 can also be obliquely downwardly arranged. When ignition is needed, the high-pressure air is sequentially sent from the end cover high-pressure air inlet pipe 19, the end cover air inlet passage 20, the end cover gas collecting annular cavity 21 to the high-pressure air injection hole 22, and is injected from the high-pressure air injection hole 22 to the piston 11, so as to push the piston 11 to move towards the mounting flange 16, so that the ignition rod 1 is from the retracted state to the extended state, and finally the ignition end of the ignition rod 1 extends into the gas passage b. In this embodiment, the high-pressure air injection hole 22 is uniformly arranged with 8-12 high-pressure air injection holes along the circumferential direction of the ignition rod 1, and / or the diameter of the high-pressure air injection hole 22 is 3mm-6mm.

[0061] The mounting flange 16 is also provided with the through hole 161 for the ignition rod 1 to extend and retract. The through hole 161 is provided with the mounting flange conical sealing surface 24 at the end towards the piston 11, and the mounting flange conical sealing surface 24 is continuously arranged around the through hole 161. The mounting flange 16 is also provided with the mounting flange air inlet passage 26, the mounting flange gas collecting annular cavity 27 and the sealing air passage 28 which are sequentially communicated. The sealing air passage 28 is communicated with the through hole 161, and the sealing air passage 28 is continuously arranged around the through hole 161. The height of the sealing air passage 28 is 1mm-3mm, and / or the sealing air passage 28 is obliquely downwardly extended, and the included angle between the sealing air passage 28 and the central axis of the ignition rod 1 is 15°-45°, which can better isolate the high-temperature gas and the annular cavity air from entering the cylinder cavity 18 during the retraction of the ignition rod 1.

[0062] When the ignition rod 1 starts to withdraw from the gas passage b after the ignition is successful, high-pressure air is blown into the through hole 161 through the installation flange high-pressure air inlet pipe 25, the installation flange air inlet passage 26, the installation flange air collection ring cavity 27, and the sealing air passage 28, and the high-pressure air is obliquely sprayed downward into the gap between the ignition rod 1 and the through hole 161 to form a blocking air flow, so as to block the air in the air collection ring passage a from entering the cylinder cavity 18 of the ignition electrode 35, reduce the risk of the ignition rod 1 of the ignition electrode 35 being ablated, and improve the service life of the ignition electrode 35. Of course, the aforementioned high-pressure air sprayed into the through hole 161 will enter the air collection ring passage a. The reason for blocking the air in the air collection ring passage a from entering the ignition electrode 35 is that the temperature of the air in the air collection ring passage a is usually 400-500°C, and if the high-temperature air collection ring air enters the ignition electrode 35, it will affect the elasticity of the return spring 12, slow down the speed of the return spring 12 pushing the piston 11 back to the original position, and accordingly, the speed of the ignition end of the ignition rod 1 withdrawing from the gas passage b will be slowed down, and the risk of the ignition rod 1 of the ignition electrode 35 being ablated by the high-temperature gas in the gas passage b will also increase. In this embodiment, the pressure of the high-pressure air is 0.8-1 MPa, but it can also be other values, which can be set according to actual needs, and is not limited here.

[0063] The piston 11 is located in the cylinder 10. The piston 11 includes coaxially arranged outer and inner cylinder walls and a top wall connecting the outer and inner cylinder walls. The inner cylinder wall of the piston 11 is fixedly connected with the ignition rod 1, and the outer cylinder wall of the piston 11 is in sliding fit with the inner side wall of the cylinder 10. The top end of the piston 11 is continuously provided to connect the outer and inner cylinder walls, and the bottom end of the piston 11 is open, so that an open downward accommodating groove is formed between the outer and inner cylinder walls. Three piston rings 345 are sequentially mounted on the outer cylinder wall of the piston 11, which are respectively a first-stage piston ring 13, a second-stage piston ring 14, and a third-stage piston ring 15. The openings of the three piston rings 345 are sequentially staggered by 180°, so as to avoid gas leakage when the piston 11 moves and ensure that the ignition rod 1 can quickly and reliably extend into the gas passage b. In this embodiment, the thickness of each piston ring 345 is 2 mm

[0064] In particular, the lower end of the inner cylinder wall of the piston 11 is provided with a piston conical sealing surface 17. The piston conical sealing surface 17 is continuously arranged towards the installation flange 16 and around the ignition rod 1. When the ignition rod 1 is in the extended state, the piston conical sealing surface 17 is tightly fitted with the installation flange conical sealing surface 24, which can prevent high-temperature gas and air collection ring air from entering the ignition electrode 35. The continuous arrangement of the piston conical sealing surface 17 and the installation flange conical sealing surface 24 can better block the air collection ring air and the high-temperature gas from entering the cylinder cavity 18.

[0065] The reset spring 12 is a compression spring, which is used to push the piston 11 to the end cover 7, so as to drive the ignition rod 1 fixedly connected with the piston 11 from the extended state to the retracted state. One end of the reset spring 12 enters the accommodating groove and is connected with the top end of the piston 11, and the other end is connected with the mounting flange 16. When the ignition rod 1 is in the retracted state, the reset spring 12 only supports the piston 11 upward, and the compression degree of the reset spring 12 by the piston 11 is limited.

[0066] The working process of the telescopic heavy-duty gas turbine ignition electrode with the pneumatic structure provided in the embodiment will be introduced as follows:

[0067] High-pressure air is introduced into the end cover air inlet channel 20, and then sequentially enters the end cover gas collecting ring cavity 21, the high-pressure air injection hole 22, and is sprayed from the high-pressure air injection hole 22 to the piston 11, so as to push the piston 11 to move to the mounting flange 16, and finally drive the ignition end of the ignition rod 1 fixedly connected with the piston 11 to enter the gas passage b, and the piston conical sealing surface 17 is tightly attached to the mounting flange conical sealing surface 24, so as to prevent the high-temperature combustion gas and the ring cavity air from entering the ignition electrode 35. Of course, during the movement of the piston 11 to the mounting flange 16, the reset spring 12 is compressed.

[0068] High-voltage electricity is loaded to the ignition rod 1, the air between the ignition anode 2 and the ignition rod shell 3 acting as the cathode is broken down and discharged to form a spark, and the spark ignites the combustible mixed gas in the gas passage b;

[0069] After confirming the successful ignition, the high-pressure air in the cylinder cavity 18 is sequentially discharged outward through the high-pressure air injection hole 22, the end cover gas collecting ring cavity 21 and the end cover air inlet channel 20, the pressure on the top end of the piston 11 is reduced, the elastic restoring force of the compressed reset spring 12 pushes the piston 11 to move to the end cover 7, so as to make the piston 11 return to the original position. During the process of the piston 11 returning to the original position, the piston 11 drives the ignition rod 1 fixedly connected therewith to move upward, and finally reaches the retracted state, and the ignition end of the ignition rod 1 exits the combustion chamber b.

[0070] When the ignition rod 1 starts to exit the combustion chamber b, the high-pressure air enters from the mounting flange air inlet channel 26, and then sequentially enters the mounting flange gas collecting ring cavity 27 and the sealing air channel 28, and is sprayed downward from the sealing air channel 28 to the gap between the ignition rod 1 and the through hole 161, and finally enters the ring cavity air channel a, so as to prevent the ring cavity air and the high-temperature combustion gas from entering the ignition electrode 35 through the gap between the ignition rod 1 and the through hole 161, and affect the elasticity of the reset spring 12. Since the sealing air channel 28 is continuously arranged around the through hole 161, a continuous air flow is formed, so as to avoid the ablation of the ignition electrode 35 and prolong the service life of the ignition electrode 35. In addition, since the temperature of the high-pressure air is lower than that of the ring cavity air and the high-temperature combustion gas, the high-pressure air can also be used to cool the ignition rod and the cylinder cavity

[0071] In summary, in this embodiment, when the ignition rod 1 is in the retracted state, the high-pressure air ejected from the sealed air passage 28 prevents the annular cavity air and high-temperature gas from entering the ignition nozzle 35. When the ignition rod 1 is in the extended state, the tight fit between the piston conical sealing surface 17 and the mounting flange conical sealing surface 24 prevents the annular cavity air and high-temperature gas from entering the ignition nozzle 35. This dual protection can better prevent the annular cavity air and high-temperature gas from entering the ignition nozzle 35, thereby improving the service life of the ignition nozzle 35.

[0072] Example 2

[0073] like Figures 1 to 5 As shown, this embodiment provides a retractable heavy-duty gas turbine ignition system with a pneumatic structure. The ignition system includes an end-cap high-pressure air inlet pipe 19, an air pump 30, a pressure regulating valve 31, a reversing control valve 32, a control device 33, an energy storage device 34, a flame detector (not shown), a mounting flange high-pressure air inlet pipe 25, and an ignition nozzle 35. In this embodiment, the reversing control valve 32 is specifically selected as a two-position four-way solenoid reversing valve.

[0074] A two-position four-way solenoid directional valve is connected to an air pump 30 via a pipeline, and a pressure regulating valve 31 is installed on this pipeline. The two-position four-way solenoid directional valve includes interface I, interface C, interface O, and interface D. The energy storage device 34 is electrically connected to the ignition rod 1. In this embodiment, the energy storage device 34 is a pressure boosting device, and the energy storage device 34 is connected to a power source. One end of the end cap high-pressure air inlet pipe 19 is connected to interface C of the two-position four-way solenoid directional valve, and the other end is connected to the end cap air inlet channel 20. One end of the mounting flange high-pressure air inlet pipe 25 is connected to interface D of the two-position four-way solenoid directional valve, and the other end is connected to the mounting flange air inlet channel 26. Flame detectors are installed on the flame tube wall c. When two or more (including two) flame detectors on the flame tube wall c show a stable flame, it indicates successful ignition. The flame signals detected by two or more flame detectors form a stop ignition signal. It is also equipped with a timing element to calculate the ignition duration. If the ignition duration reaches 15 seconds, ignition will stop regardless of whether ignition is successful or not, and a stop ignition signal will be generated. The control device 33 is electrically connected to the two-position four-way solenoid valve, the energy storage device 34, and the flame detector.

[0075] The control device 33 controls the two-position four-way electromagnetic reversing valve to open the charging path from the air pump 30 to the end cover high-pressure intake pipe 19 according to the ignition signal, and controls the energy storage device 34 to load high voltage to the ignition rod 1; the control device 33 controls the two-position four-way electromagnetic reversing valve to close the charging path from the air pump 30 to the end cover high-pressure intake pipe 19 according to the stop ignition signal, and controls the two-position four-way electromagnetic reversing valve to open the exhaust path from the end cover high-pressure intake pipe 19 via the two-position four-way electromagnetic reversing valve, and controls the two-position four-way electromagnetic reversing valve to open the charging path from the air pump 30 to the mounting flange high-pressure intake pipe 25.

[0076] Specifically, when the gas turbine needs to be ignited, on the one hand, the control device 33 controls the two-position four-way electromagnetic reversing valve to enter the ignition state according to the ignition signal, that is, the two-position four-way electromagnetic reversing valve is in the pass-through state from the interface I to the interface C, and is also in the pass-through state from the interface D to the interface O, so that the high-pressure air generated by the air pump 30 can enter the end cover high-pressure intake pipe 19 from the A port through the pressure regulating valve 31 and the two-position four-way electromagnetic reversing valve, and then sequentially reach the end cover intake passage 20, the end cover gas collecting ring cavity 21, the high-pressure air injection hole 22, and be sprayed out from the high-pressure air injection hole 22 to enter the cylinder cavity 18, so that the air pressure above the top end of the piston 11 increases, the piston 11 is pushed to move towards the mounting flange 16, thereby driving the ignition end of the ignition rod 1 fixedly connected with the piston 11 to enter the fuel passage b. On the other hand, the control device 33 starts the energy storage device 34 according to the ignition signal, so that the high-voltage electric energy of tens of thousands of volts is loaded on the ignition rod 1, the air between the ignition anode 2 and the ignition rod shell 3 acting as the cathode is broken down and discharged to form a spark, and the combustible mixed gas in the fuel passage b is ignited. When two or more flame detectors in the combustion chamber detect a flame detection signal, it indicates that the ignition is successful, the ignition signal is cut off, of course, even if the ignition fails, but the ignition time lasts for 15s, the ignition signal will still be cut off, and the next ignition is waited for. When the ignition signal is cut off, the control device 33 controls the two-position four-way electromagnetic reversing valve to enter the normal state according to the stop ignition signal, that is, the two-position four-way electromagnetic reversing valve is in the pass-through state from the interface I to the interface D, and is in the pass-through state from the interface C to the interface O, the high-pressure air in the cylinder cavity 18 is quickly vented through the A port, the interface C and the interface O in sequence, the piston 11 moves towards the end cover 7 under the elastic restoring force of the reset spring 12, and drives the ignition end of the ignition rod 1 to quickly exit the fuel passage b. At the same time, the high-pressure air generated by the air pump 30 enters the mounting flange high-pressure intake pipe 25 from the B port through the pressure regulating valve 31 and the two-position four-way electromagnetic reversing valve, and then sequentially enters the mounting flange intake passage 26, the mounting flange gas collecting ring cavity 27, the sealing air passage 28, and is finally sprayed downward from the sealing air passage 28 to the gap between the ignition rod 1 and the through hole 161, and finally enters the annular cavity air passage a, so as to prevent the annular cavity air and the high-temperature fuel gas from entering the ignition electrode 35 through the gap between the ignition rod 1 and the through hole 161, and affecting the elasticity of the reset spring 12, thereby avoiding the ignition electrode 35 from being ablated, and prolonging the service life of the ignition electrode 35.

[0077] In the ignition system provided in the embodiment, all advantages of the ignition electrode 35 are achieved.

[0078] In addition, in the embodiment, the ignition is stopped based on the ignition duration time as well as the flame detector, so that the service life of the ignition device can be prevented from being shortened due to long-time invalid ignition of the ignition device.

[0079] Obviously, the above embodiments are merely example for clearly illustrating but not limitation to the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments need not and can not be enumerated. The obvious changes or variations derived from the above description are still within the protection scope of the present application.

Claims

1. A retractable heavy-duty gas turbine igniter tip with pneumatic structure, characterized by, The ignition electrode (35) comprises: A cylinder cavity (18) comprising oppositely arranged end cover (7) and mounting flange (16), the mounting flange (16) is provided with through hole (161); Piston (11), slidingly arranged along the inner side wall of the cylinder cavity (18); Reset spring (12), between the piston (11) and the mounting flange (16); Ignition rod (1), telescopic through the end cover (7) into the cylinder cavity (18), and fixedly connected with the piston (11), the ignition rod (1) into the through hole (161); wherein, The mounting flange (16) is provided with mounting flange air inlet channel (26), mounting flange gas collecting ring cavity (27) and sealing air channel (28) which are communicated in sequence, the sealing air channel (28) is communicated with the through hole (161), and the high pressure air from the sealing air channel (28) is suitable for being sprayed downward to the gap between the through hole (161) and the ignition rod (1), forming the blocking airflow; The piston (11) is provided with piston conical sealing surface (17) at one end towards the mounting flange (16), the through hole (161) is provided with mounting flange conical sealing surface (24) at one end towards the piston (11), in the ignition state of the ignition electrode (35), the piston conical sealing surface (17) is closely combined with the mounting flange conical sealing surface (24).

2. The retractable heavy-duty gas turbine igniter with pneumatic structure according to claim 1, characterized in that, The sealing air channel (28) is continuously arranged around the through hole (161).

3. The retractable heavy-duty gas turbine igniter with pneumatic structure of claim 1, wherein, The height of the sealing air channel (28) is 1mm-3mm, and / or the sealing air channel (28) extends downwardly and the included angle between the sealing air channel (28) and the central axis of the ignition rod (1) is 15°-45°.

4. The retractable heavy-duty gas turbine igniter with pneumatic structure of claim 1, wherein, The mounting flange conical sealing surface (24) is continuously arranged around the through hole (161), and / or the piston conical sealing surface (17) is continuously arranged around the ignition rod (1).

5. The retractable heavy-duty gas turbine igniter with pneumatic structure of claim 1, wherein, Three piston rings (345) are sequentially mounted on the outer cylinder wall of the piston (11), and the openings of the three piston rings (345) are sequentially staggered by 180°.

6. The retractable heavy-duty gas turbine igniter with pneumatic structure according to any one of claims 1-5, characterized in that, The end cover (7) is provided with end cover air inlet channel (20), end cover gas collecting ring cavity (21) and high pressure air injection hole (22) which are communicated in sequence, and the high pressure air injection hole (22) is communicated with the cylinder cavity (18).

7. The retractable heavy-duty gas turbine igniter with pneumatic structure according to claim 6, characterized in that, The high pressure air injection hole (22) is arranged circumferentially and spaced apart along the ignition rod (1), and / or the diameter of the high pressure air injection hole (22) is 3mm-6mm.

8. A retractable heavy-duty gas turbine ignition system with pneumatic architecture, characterized in that, The ignition system comprises: The telescopic heavy gas turbine ignition electrode with pneumatic structure of claim 6; Air pump (30); Reversing control valve (32) connected with the air pump (30) through pipeline; Energy storage device (34) electrically connected with ignition rod (1); Mounting flange high pressure air inlet pipe (25) connected with the reversing control valve (32) at one end and communicated with mounting flange air inlet channel (26) at the other end; A control device (33) is electrically connected with the reversing control valve (32) and the energy storage device (34) respectively; wherein The control device (33) is adapted to control the reversing control valve (32) to open the gas charging path from the gas pump (30) to the mounting flange high-pressure intake pipe (25) according to the stop ignition signal.

9. The retractable heavy-duty gas turbine ignition system with pneumatic structure according to claim 8, characterized in that, Further comprising: An end cover high-pressure intake pipe (19) is connected with the reversing control valve (32) at one end and communicates with the end cover intake passage (20) at the other end; wherein The control device (33) is adapted to control the reversing control valve (32) to open the gas charging path from the gas pump (30) to the end cover high-pressure intake pipe (19) and control the energy storage device (34) to energize the ignition rod (1) according to the ignition signal; the control device (33) is also adapted to control the reversing control valve (32) to close the gas charging path from the gas pump (30) to the end cover high-pressure intake pipe (19) and open the exhaust path from the end cover high-pressure intake pipe (19) via the reversing control valve (32) according to the stop ignition signal.

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