Gas turbine starting temperature fault judgment method

Abstract

The invention belongs to the technical field of gas turbine starting temperature fault judgment design, and particularly relates to a gas turbine starting temperature fault judgment method, which divides the judgment of starting overtemperature into a low rotating speed stage and a high rotating speed stage, and considers the influence of rotating speed and atmospheric temperature. According to the method, a corresponding exhaust temperature threshold value for starting overtemperature judgment is obtained through interpolation calculation, starting overtemperature is judged, so that starting overtemperature can be judged in time, missed report and misjudgment are avoided, and according to main characteristics of starting heat hanging of the gas turbine, an exhaust temperature rise rate threshold value for starting heat hanging judgment can be set, so that the starting heat hanging of the gas turbine can be accurately judged after ignition succeeds. Starting heat hanging is judged, the influence of the atmospheric temperature can be eliminated, and missing report and misjudgment are avoided.

Description

Technical Field

[0001] The present application belongs to the technical field of gas turbine starting temperature fault determination design, and specifically relates to a gas turbine starting temperature fault determination method. Background Art

[0002] During the starting process of the gas turbine, temperature failures such as starting overheating or thermal shutdown may occur due to excessive fuel supply, too low gas turbine speed or compressor stall, resulting in excessively high temperature before the turbine and the risk of turbine ablation.

[0003] In order to avoid safety damage to the gas turbine caused by overheating or hot hanging during startup, a common method in engineering is to set the same exhaust temperature limit value to judge overheating and hot hanging during the startup process. When the exhaust temperature exceeds the limit value during startup, the startup overtemperature alarm is triggered. This technical solution has the following defects:

[0004] 1) Only one exhaust temperature limit value is set for judgment. The limit value is generally determined by the over-temperature level at slow speed or above. When the exhaust temperature rises to the limit value level, the start-up over-temperature or hot hang may have lasted for a period of time, and the judgment is delayed, which is very unfavorable to the operation safety and long life of the gas turbine;

[0005] 2) The exhaust temperature is significantly affected by the atmospheric temperature at certain stages. There are cases where the gas turbine overheats or heats up due to low atmospheric temperature, but the exhaust temperature is below the threshold value and is not reported, or the atmospheric temperature is too high, resulting in a very high exhaust temperature, which can lead to misjudgment.

[0006] This application is proposed in view of the above-mentioned technical defects. Summary of the invention

[0007] The purpose of the present application is to provide a method for determining a gas turbine startup temperature fault, so as to overcome or alleviate at least one of the known technical deficiencies.

[0008] The technical solution of this application is:

[0009] A method for determining a gas turbine startup temperature fault, comprising:

[0010] The judgment of starting overtemperature is divided into low speed stage and high speed stage;

[0011] The speed range of the low speed stage is from the speed at which the ignition is successful to the maximum speed of the starter.

[0012] The speed range of the high speed stage is from the maximum speed of the starter to the slow speed;

[0013] At low speed, the exhaust temperature threshold corresponding to the ignition success speed and the exhaust temperature threshold corresponding to the maximum starter speed are calculated by speed interpolation to obtain the exhaust temperature threshold for starting over-temperature judgment, and the starting over-temperature is judged;

[0014] In the high speed stage, within the range of the maximum starter speed to the slow speed, the maximum exhaust temperature threshold values ​​at different speeds are obtained according to the temperature resistance of the hot end components and the exhaust device materials, and the maximum atmospheric temperature of the gas turbine, as well as the impact of each 1°C change in atmospheric temperature on the exhaust temperature. Then, the minimum exhaust temperature threshold values ​​at different speeds corresponding to the maximum atmospheric temperature of the gas turbine are obtained. The exhaust temperature threshold values ​​for starting over-temperature judgment at the corresponding speed are obtained by interpolation of the minimum exhaust temperature threshold value and the maximum exhaust temperature threshold value according to the atmospheric temperature, and the starting over-temperature is judged.

[0015] According to at least one embodiment of the present application, in the above-mentioned gas turbine starting temperature fault judgment method, the threshold value of the exhaust temperature corresponding to the ignition successful speed and the threshold value of the exhaust temperature corresponding to the starter maximum rotation speed are determined by experiments or simulation methods.

[0016] According to at least one embodiment of the present application, in the above-mentioned gas turbine starting temperature fault judgment method, the maximum exhaust temperature threshold value at different speeds and the impact value of each 1°C change in atmospheric temperature on the exhaust temperature are determined by experiments or simulation methods.

[0017] According to at least one embodiment of the present application, in the above-mentioned gas turbine startup temperature fault determination method, the lowest exhaust temperature threshold value corresponding to the highest atmospheric temperature of the gas turbine at different speeds is T max -k(t2-t1), where

[0018] T max is the maximum exhaust temperature threshold;

[0019] k is the impact of a 1°C change in atmospheric temperature on the exhaust temperature, specifically 2°C to 3°C;

[0020] t2 and t1 are the highest and lowest atmospheric temperatures used by the gas turbine.

[0021] According to at least one embodiment of the present application, the above-mentioned gas turbine starting temperature fault judgment method also includes setting an exhaust temperature rise rate threshold value for starting hot hanging judgment. After the ignition is successful, the starting hot hanging is judged based on the exhaust temperature rise rate threshold value for starting hot hanging judgment.

[0022] According to at least one embodiment of the present application, in the above-mentioned gas turbine startup temperature fault determination method, the exhaust temperature rise rate threshold value is determined by an experimental or simulation method. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of a gas turbine starting temperature fault determination method provided in an embodiment of the present application.

[0024] 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

[0025] 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.

[0026] 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.

[0027] 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.

[0028] A method for determining a gas turbine startup temperature fault, such as Figure 1 shown.

[0029] The judgment of starting overtemperature is divided into a low speed stage and a high speed stage.

[0030] The speed range of the low-speed stage is from the speed at which the ignition is successful to the maximum speed of the starter. The exhaust temperature in this stage is not significantly affected by the atmospheric temperature.

[0031] The speed range of the high-speed stage is from the maximum starter speed to the slow speed. The exhaust temperature in this stage is significantly affected by the atmospheric temperature.

[0032] In the low speed stage, the exhaust temperature threshold value corresponding to the ignition success speed and the exhaust temperature threshold value corresponding to the starter maximum speed are calculated by speed interpolation to obtain the exhaust temperature threshold value for starting over-temperature judgment at the corresponding speed, and the starting over-temperature is judged.

[0033] The threshold value of the exhaust temperature corresponding to the ignition success speed and the threshold value of the exhaust temperature corresponding to the starter maximum rotation speed can be determined by experiments or simulation methods.

[0034] In the high speed stage, within the range of the maximum starter speed and slow speed, the maximum exhaust temperature threshold values ​​at different speeds are obtained according to the temperature resistance of the hot end components and the exhaust device materials, and the maximum atmospheric temperature of the gas turbine, as well as the impact of each 1°C change in atmospheric temperature on the exhaust temperature. Then, the minimum exhaust temperature threshold values ​​at different speeds corresponding to the maximum atmospheric temperature of the gas turbine are obtained. The exhaust temperature threshold values ​​for starting over-temperature judgment at the corresponding speed are obtained by interpolation of the minimum exhaust temperature threshold value and the maximum exhaust temperature threshold value according to the atmospheric temperature, and the starting over-temperature is judged.

[0035] The maximum exhaust temperature threshold value at different speeds and the impact value of each 1°C change in atmospheric temperature on the exhaust temperature can be determined through experiments or simulation methods.

[0036] The minimum exhaust temperature threshold value corresponding to the highest atmospheric temperature of the gas turbine at different speeds is T max -k(t2-t1), where T max is the maximum exhaust temperature threshold value; k is the impact value of every 1°C change in atmospheric temperature on the exhaust temperature, which can be specifically taken as 2°C~3°C; t2 and t1 are the highest and lowest atmospheric temperatures used by the gas turbine, which are the design values ​​of the gas turbine.

[0037] The main characteristic of gas turbine hot start is that after the gas turbine is successfully ignited, the gas turbine speed does not increase, but the exhaust temperature rises rapidly. Therefore, the exhaust temperature rise rate threshold value for hot start judgment can be set. After successful ignition, the hot start is judged based on the exhaust temperature rise rate threshold value for hot start judgment.

[0038] The exhaust temperature rise rate threshold value can be determined through experiments or simulation methods.

[0039] The gas turbine starting temperature fault judgment method disclosed in the above embodiment divides the judgment of starting overtemperature into a low speed stage and a high speed stage, and considers the influence of the speed and the atmospheric temperature, interpolates and calculates the corresponding exhaust temperature threshold value for starting overtemperature judgment, and judges the starting overtemperature, so that the starting overtemperature can be judged in time to avoid missing reports and misjudgments, and according to the main characteristics of the gas turbine starting hot hanging, the exhaust temperature rise rate threshold value for starting hot hanging judgment can be set. After the ignition is successful, the starting hot hanging is judged, which can eliminate the influence of the atmospheric temperature and avoid missing reports and misjudgments.

[0040] 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 method for determining a gas turbine startup temperature fault, characterized in that: include: The judgment of starting overtemperature is divided into low speed stage and high speed stage; The speed range of the low speed stage is from the speed at which the ignition is successful to the maximum speed of the starter. The speed range of the high speed stage is from the maximum speed of the starter to the slow speed; At low speed, the exhaust temperature threshold corresponding to the ignition success speed and the exhaust temperature threshold corresponding to the maximum starter speed are calculated by speed interpolation to obtain the exhaust temperature threshold for starting over-temperature judgment, and the starting over-temperature is judged; In the high speed stage, within the range of the maximum starter speed and slow speed, the maximum exhaust temperature threshold values ​​at different speeds are obtained according to the temperature resistance of the hot end components and the exhaust device materials, and the maximum atmospheric temperature of the gas turbine, as well as the impact of each 1°C change in atmospheric temperature on the exhaust temperature. Then, the minimum exhaust temperature threshold values ​​at different speeds corresponding to the maximum atmospheric temperature of the gas turbine are obtained. The exhaust temperature threshold values ​​for starting over-temperature judgment at the corresponding speed are obtained by interpolation of the minimum exhaust temperature threshold value and the maximum exhaust temperature threshold value according to the atmospheric temperature, and the starting over-temperature is judged.

2. The gas turbine startup temperature fault determination method according to claim 1, characterized in that: The threshold value of the exhaust temperature corresponding to the ignition success speed and the threshold value of the exhaust temperature corresponding to the starter maximum rotation speed are determined by experiments or simulation methods.

3. The method for determining a gas turbine startup temperature fault according to claim 1, characterized in that: The maximum exhaust temperature threshold value at different speeds and the impact value of each 1°C change in atmospheric temperature on the exhaust temperature are determined through experiments or simulation methods.

4. The method for determining a gas turbine startup temperature fault according to claim 1, characterized in that: The minimum exhaust temperature threshold value corresponding to the highest atmospheric temperature of the gas turbine at different speeds is T max -k(t2-t1), where T max is the maximum exhaust temperature threshold; k is the impact of a 1°C change in atmospheric temperature on the exhaust temperature, specifically 2°C to 3°C; t2 and t1 are the highest and lowest atmospheric temperatures used by the gas turbine.

5. The method for determining a gas turbine startup temperature fault according to claim 1, characterized in that: The exhaust temperature rise rate threshold is determined by experiments or simulation methods.

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