Distributed starting ignition method for single-tube combustion chamber of gas turbine

Abstract

The invention belongs to the technical field of gas turbine single-tube combustion chamber ignition design, and particularly relates to a gas turbine single-tube combustion chamber distributed starting ignition method which comprises the steps that firstly, according to the difficulty of successful ignition, single-tube combustion chambers are divided into multiple sets; secondly, when ignition is started, ignition is conducted on the single-tube combustion chambers in sequence from difficult to easy; and thirdly, whether ignition of the gas turbine succeeds or not is judged, and if ignition of the gas turbine fails, emergency stop is executed.

Description

Technical Field

[0001] The present application belongs to the technical field of ignition design of a single-tube combustion chamber of a gas turbine, and specifically relates to a distributed starting ignition method of a single-tube combustion chamber of a gas turbine. Background Art

[0002] In order to meet the development needs of low emissions, more and more gas turbines are using single-tube combustion chamber solutions with lean fuel premixed combustion. Different from the conventional diffusion combustion chamber head intake ratio of about 20%, most of the air in the low-emission single-tube combustion chamber enters from the head to participate in combustion. The increase in the head air volume reduces the average equivalence ratio of the combustion chamber head, which seriously affects the stability of starting ignition.

[0003] Currently, the design of starting ignition of a single-tube combustion chamber for lean fuel premixed combustion is based on a synchronous ignition method. Due to the different fuel filling sequences, the single-tube combustion chamber closer to the fuel main pipe is generally filled with fuel first. During synchronous ignition, the fuel concentration is relatively high and it is easier to ignite successfully. The single-tube combustion chamber farther from the fuel main pipe is filled with fuel later. During synchronous ignition, the fuel concentration is relatively low and will be disturbed by the local high pressure generated by the successfully ignited single-tube combustion chamber, making it difficult to ignite successfully. In addition, due to the differences in the ignition characteristics of the single-tube combustion chambers themselves, there are individual single-tube combustion chambers that are difficult to ignite successfully. During synchronous ignition, they will also be disturbed by the local high pressure generated by the successfully ignited single-tube combustion chamber, making it difficult to ignite successfully.

[0004] This application is proposed in view of the above-mentioned technical defects. Summary of the invention

[0005] The purpose of the present application is to provide a distributed starting and ignition method for a single-tube combustion chamber of a gas turbine, so as to overcome or alleviate at least one aspect of the known technical defects.

[0006] The technical solution of this application is:

[0007] A distributed starting ignition method for a single-tube combustion chamber of a gas turbine, comprising:

[0008] Step 1: Divide the single-tube combustion chamber into multiple groups according to the difficulty of successful ignition;

[0009] Step 2: When starting the ignition, ignite each group of single-tube combustion chambers in sequence from difficult to easy;

[0010] Step 3: Determine whether the gas turbine ignition is successful. If the gas turbine ignition fails, perform an emergency stop.

[0011] According to at least one embodiment of the present application, in the above-mentioned gas turbine single-tube combustion chamber distributed starting ignition method, step 1 is specifically as follows:

[0012] The single-tube combustion chambers are divided into multiple groups according to their distance from the fuel main pipe. The single-tube combustion chambers that are closer to the fuel main pipe are single-tube combustion chambers that are easier to ignite successfully, and the single-tube combustion chambers that are farther from the fuel main pipe are single-tube combustion chambers that are more difficult to ignite successfully.

[0013] According to at least one embodiment of the present application, in the above-mentioned gas turbine single-tube combustion chamber distributed starting and ignition method, in step two, when starting and igniting, the time interval for ignition of adjacent groups of single-tube combustion chambers is the time length from the start of ignition of the single-tube combustion chamber to the successful ignition.

[0014] According to at least one embodiment of the present application, in the above-mentioned gas turbine single-tube combustion chamber distributed starting and ignition method, in step 2, during starting and ignition, the time interval between ignitions of adjacent groups of single-tube combustion chambers is 0.3 to 1 second.

[0015] According to at least one embodiment of the present application, in the above-mentioned gas turbine single-tube combustion chamber distributed starting ignition method, in step three, if the flame detector signals of each single-tube combustion chamber reach the threshold of successful ignition, and the speed Ng of the gas generator of the gas turbine is greater than the maximum speed Nq+500r / min driven by the starter alone, it is judged that the gas turbine ignition is successful; if not, it is judged that the gas turbine ignition has failed. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of a distributed starting and ignition method for a single-tube combustion chamber of a gas turbine provided in an embodiment of the present application;

[0017] Figure 2 It is a schematic diagram of a distributed starting and ignition method for a single-tube combustion chamber of a gas turbine provided in an embodiment of the present application.

[0018] In order to better illustrate the present embodiment, some contents of the drawings may be omitted, which is only used for illustrative purposes and should not be construed as limiting the present application. DETAILED DESCRIPTION

[0019] In order to make the technical solution and advantages of the present application clearer, the technical solution of the present application will be described in further detail in detail and in detail with reference to the accompanying drawings. It can be understood that the specific embodiments described here are only partial embodiments of the present application, which are only used to explain the present application, not to limit the present application. It should be noted that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings, and other related parts can refer to the general design.

[0020] In addition, unless otherwise defined, the technical terms or scientific terms used in the description of this application shall have the usual meanings understood by those of ordinary skill in the art to which this application belongs. The words used in the description of this application to indicate orientation are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. The word "include" used in the description of this application indicates that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, but does not exclude other elements or objects.

[0021] In addition, it should be noted that, unless otherwise clearly specified and limited, the words "installation", "connection" and similar terms used in the description of this application should be understood in a broad sense. For example, the connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Technical personnel in the field can understand its specific meaning in this application according to the specific circumstances.

[0022] A distributed starting and ignition method for a single-tube combustion chamber of a gas turbine is specifically described as follows.

[0023] Step 1: Divide the single-tube combustion chamber into multiple groups according to the difficulty of successful ignition.

[0024] Specifically, the single-tube combustion chambers can be divided into multiple groups according to their distance from the fuel main pipe, that is, according to the order of filling fuel. The single-tube combustion chambers closer to the fuel main pipe are single-tube combustion chambers that are easier to ignite successfully, and the single-tube combustion chambers farther from the fuel main pipe are single-tube combustion chambers that are more difficult to ignite successfully. At the same time, individual single-tube combustion chambers that are difficult to ignite successfully can also be divided into the single-tube combustion chamber group that is more difficult to ignite successfully.

[0025] Step 2: When starting the ignition, ignite each group of single-tube combustion chambers in sequence from difficult to easy.

[0026] That is, the single-tube combustion chambers in the group that are more difficult to ignite successfully are ignited first, and then the single-tube combustion chambers in the group that are easier to ignite successfully are ignited. This can avoid the situation where, during synchronous ignition, the successful ignition of the single-tube combustion chamber that is easier to ignite successfully interferes with the ignition of the single-tube combustion chamber that is more difficult to ignite successfully, making the ignition of the single-tube combustion chamber that is more difficult to ignite successfully more difficult, thereby ensuring the successful ignition of each single-tube combustion chamber.

[0027] The time interval for ignition of adjacent groups of single-tube combustion chambers is the time from the start of ignition of a single-tube combustion chamber to successful ignition, which can be determined by experiment or simulation, and can be specifically 0.3 to 1 second.

[0028] Step 3: Determine whether the gas turbine ignition is successful. If the gas turbine ignition fails, perform an emergency stop.

[0029] If the flame detector signals of each single-tube combustion chamber reach the threshold of successful ignition, and the speed Ng of the gas generator of the gas turbine is greater than the maximum speed Nq+500r / min driven by the starter alone, it is judged that the gas turbine ignition is successful. If not, it is judged that the gas turbine ignition has failed and an emergency stop is executed.

[0030] In a specific embodiment, there are 8 single-tube combustion chambers, which are No. 1, No. 2, No. 3, No. 4, No. 5, No. 6, No. 7, and No. 8 in order of their distance from the fuel main pipe. Figure 1 As shown, the ignition is performed using the distributed starting ignition method for a single-tube combustion chamber of a gas turbine disclosed in the above embodiment, which can be specifically designed as follows.

[0031] Step 1: Use 7# and 8# single-tube combustion chambers as the first group of single-tube combustion chambers, 4#, 5#, and 6# single-tube combustion chambers as the second group of single-tube combustion chambers, and 1#, 2#, and 3# single-tube combustion chambers as the third group of single-tube combustion chambers. They can also be divided into more groups.

[0032] Step 2. After receiving the start ignition command from the upper system, the control cabinet sends a signal to turn on the igniter, and the multiple igniter power supplies are energized to the igniters of the first group of single-tube combustion chambers, so that the corresponding igniters start to work continuously and ignite the first group of single-tube combustion chambers. After an interval of t seconds, the control cabinet controls the multiple igniter power supplies to energize the igniters of the second group of single-tube combustion chambers, so that the corresponding igniters start to work continuously and ignite the second group of single-tube combustion chambers. After an interval of 2t seconds, the control cabinet controls the multiple igniter power supplies to energize the igniters of the third group of single-tube combustion chambers, so that the corresponding igniters start to work continuously and ignite the third group of single-tube combustion chambers.

[0033] Step 3: If the flame detector signals of each single-tube combustion chamber reach the threshold of successful ignition, and the speed Ng of the gas generator of the gas turbine is greater than the maximum speed Nq+500r / min of the starter alone, it is judged that the gas turbine ignition is successful. Otherwise, it is judged that the gas turbine ignition fails, and an emergency stop is performed. Afterwards, the single-tube combustion chambers can be regrouped according to the difficulty of successful ignition, and the time interval for ignition of adjacent groups of single-tube combustion chambers can be readjusted to restart and ignite again until the gas turbine ignites successfully. Figure 2 shown.

[0034] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of the present application is obviously not limited to these specific embodiments. Without departing from the principles of the present application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the scope of protection of the present application.

Claims

1. A distributed starting ignition method for a single-tube combustion chamber of a gas turbine, characterized in that: include: Step 1: Divide the single-tube combustion chamber into multiple groups according to the difficulty of successful ignition; Step 2: When starting the ignition, ignite each group of single-tube combustion chambers in sequence from difficult to easy; Step 3: Determine whether the gas turbine ignition is successful. If the gas turbine ignition fails, perform an emergency stop.

2. The gas turbine single-tube combustion chamber distributed starting ignition method according to claim 1, characterized in that: Step 1 is as follows: The single-tube combustion chambers are divided into multiple groups according to their distance from the fuel main pipe. The single-tube combustion chambers that are closer to the fuel main pipe are single-tube combustion chambers that are easier to ignite successfully, and the single-tube combustion chambers that are farther from the fuel main pipe are single-tube combustion chambers that are more difficult to ignite successfully.

3. The distributed starting ignition method for a gas turbine single-tube combustion chamber according to claim 1, characterized in that: In step 2, when starting the ignition, the time interval for ignition of adjacent groups of single-tube combustion chambers is the time from the start of ignition to the successful ignition of the single-tube combustion chamber.

4. The gas turbine single-tube combustion chamber distributed starting ignition method according to claim 3, characterized in that: In step 2, when starting the ignition, the time interval for ignition of adjacent groups of single-tube combustion chambers is 0.3 to 1 second.

5. The gas turbine single-tube combustion chamber distributed starting ignition method according to claim 1, characterized in that: In step three, if the flame detector signals of each single-tube combustion chamber reach the threshold of successful ignition, and the speed Ng of the gas generator of the gas turbine is greater than the maximum speed Nq+500r / min driven by the starter alone, it is judged that the gas turbine ignition is successful. If not, it is judged that the gas turbine ignition has failed.

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