JP2666974B2 - Gas turbine life monitoring device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a gas turbine life monitoring device applied to a combined cycle power plant or the like.

(Prior Art) A gas turbine is based on a Brayton cycle using air and combustion gas as a working medium, and has a feature that heat can be used from a relatively high temperature. In addition, with the progress of the combined cycle in recent years, various studies have been conducted with the aim of a highly efficient gas turbine having a high combustion temperature.

Incidentally, in order to improve the thermal efficiency of gas turbine power generation, it is important to increase the gas temperature at the turbine inlet, that is, the combustion temperature. Combustion temperature is generally about 1100 ° C, but recently 1300 ° C has also been manufactured, and the temperature tends to be higher in the future.

For the material of the high temperature part of the gas turbine (combustor liner, transition piece, etc.), materials suitable for each use condition are used, but even if a material with high heat resistance is used, in the case of long-term use, It is necessary to properly manage the service life and perform periodic inspections or replacements before the gas turbine accidentally shuts down due to destruction of components.

Conventionally, gas turbine power generation has mainly been used for emergency power generation or peak load use. However, recently developed combined cycle power generation has become as important as a power source equivalent to thermal power generation.

In a combined cycle power plant, many gas turbines are used, and one unit is constituted by a plurality of combined cycle shafts combined with an HRSG and a steam turbine. When the gas turbine and the steam turbine each generate electric power and are fully operating as a unit, all the turbines are operated. On the other hand, in the case where the state of low power generation demand continues for a long time (for example, on weekends, at night, etc.), when the gas turbine is operated under partial load, the thermal efficiency of the entire unit is reduced. It is common to shut down the gas turbine. In this case, it is necessary to select the gas turbine to be stopped so that the life consumption of all the gas turbines becomes uniform over a long period of time. In addition, it is necessary to draft a maintenance schedule for each gas turbine in advance in terms of unit operation, and to select a gas turbine to be operated in accordance with the schedule.

Conventionally, as a means for obtaining a measure of the life consumption of high-temperature components such as gas turbines with severe thermal fatigue, for example, combustor liners and transition pieces, the combustion time of the gas turbine and the number of start / stop times were used as parameters. Empirical curves are used for management. In this case, of the above two parameters, the burning time is an index of the impact on the constituent material when the component is continuously exposed to a high temperature. The number of times of starting and stopping is an index in consideration of a thermal shock at the time of ignition or misfire.

FIG. 3 shows a management curve of a combustor liner as an example of a management curve. In FIG. 3, the horizontal axis represents the number of start / stop (logarithm) of the gas turbine, and the vertical axis represents the combustion time. In this example, the axis trace a indicated by an arrow in the drawing indicates a time change of the consumption tendency of the life, and when the axis trace a of the arrow reaches the inspection line b, the gas turbine is stopped and inspected. The inspection line b is given as a different curve depending on the component. 1 operator
While adding the combustion time integrated value of each start and stop, it is plotted on the figure to check the life consumption degree, and when it reaches the inspection line, the regular inspection is stopped and the presence or absence of abnormality is checked.

(Problems to be Solved by the Invention) Since gas turbines have been used on a small scale for emergency use or peak load use, and the combustion temperature is relatively low, the life of the gas turbine is controlled by the operator's record. Was enough. However, such as gas turbines used in recent combined cycles, which are used as important power sources, have high combustion temperatures, and the need to simultaneously manage the life of multiple gas turbines is increasing. Simple life management by hand calculation is becoming insufficient. That is, recently, accurate calculation of life consumption, instruction of appropriate life consumption degree, recording and display, and the like are required.

In addition, the provision of information necessary for selecting the appropriate start and stop of the gas turbine shaft based on the comparison of the life consumption of multiple units,
This is important for the smooth operation of one combined cycle including a plurality of gas turbines.

The present invention has been made in view of such circumstances, and from the operating conditions of individual gas turbines required for the evaluation of life,
It is an object of the present invention to provide a life management system having a function of automatically and accurately calculating the life consumption of each gas turbine, displaying information on an appropriate life, and instructing an inspection time.

[Configuration of the invention]

(Means for Solving the Problems) The present invention is directed to a combustion time integration unit that takes in combustion time data from a plurality of gas turbine shafts to be monitored as needed and integrates the data, and the number of start / stop times of each of the gas turbine shafts The start / stop count integrating unit that takes in the data of the time and accumulates the data at any time, based on the combustion time integrated value and the start / stop count integrated value output from the combustion time integrating unit and the start / stop count integrating unit, respectively. A life consumption calculator for calculating a life consumption relative value corresponding to a constituent material of a high-temperature part,
The life consumption relative value calculated by the life consumption calculation unit is compared, and it is determined whether the inspection time set in advance for each gas turbine shaft has been reached, the display thereof, and the information processing for automatically generating an alarm and other information processing. The life consumption calculator includes a combustion time integrated value y,
When the integrated value of the number of stops is x, the relative value K of the life consumption is calculated as y + logx = K.

(Operation) According to the above configuration, the present invention is based on the integrated value of the operation time (combustion time) and the number of start / stop of each gas turbine,
Evaluate the life consumption of each gas turbine, display the results, generate an alarm, etc., use it as a guideline for the inspection timing of each gas turbine, and compare the life consumption between multiple axes of the gas turbine. Thus, a determination is made for selecting which shaft of the gas turbine is to be started or stopped.

In this case, in the present invention, the logarithmic value “a logx” of the integrated value “x” of the number of times of start / stop evaluates the equivalent operation time (combustion time). “Y + a logx” which is the sum of “y” is calculated as the life consumption degree. That is, in order to present the degree of life consumption at the present time as an objective numerical value, in the present invention, specifically, the operation time “y” and the number of start / stop times “x”
And the two parameters “K = y + a log
They are related by the relational expression "x".

Therefore, for example, it is possible to indicate how much the current life consumption is progressing with respect to the life consumption degree K that requires inspection for one axis, and this can be an accurate guide for the inspection time. Further, for example, two axes having extremely different operation patterns (an axis that is continuously operated without starting and stopping,
Conversely, if there is an axis whose start and stop are frequently repeated), it can be objectively determined by comparing the value of K which life consumption is progressing.

Specifically, as shown in FIG. 3 of the present application, when the gas turbine operation time (combustion time) is y and the number of starts / stops is x, the inspection is performed when the value of K = y + a logx reaches a predetermined value. The focus is on the point of the line (straight line: b). Then, comparison of lifetime consumption between multiple axes, as illustrated in FIG. 2, No.1 axis y operation until the present time period and the start and stop times and each _A, x _A No.2 axis Zorezore y _B operating time and the start and stop times of up to the present time, when the x _B, respectively lifetime consumption of the is evaluated as follows.

Lifetime consumption degree at the current time of No.1 _{Axis: K A = y A + a} logx lifetime consumption degree at the current time point _A No.2 _{axis: K B = y B + a} logx B Then, No.1 shaft and No .Comparison of life consumption of 2-axis is K _A and K _B
It is done by comparing the size of.

That is, according to the present invention, the relative value of the life consumption of the high-temperature section is accurately and automatically determined for each gas turbine by the signal indicating the operation history that is a measure of the life consumption, that is, the combustion time integrated product value and the start / stop count integrated value. Calculation, recording, output display to the operator, and the like.

Further, by outputting the relative value signal of the life consumption amount, it becomes a guide for selecting the start / stop axis of the gas turbine due to the load change, and useful information for predicting the periodic inspection time is obtained.

(Embodiment) An embodiment of the present invention will be described below with reference to FIG. 1 and FIG.

FIG. 1 shows the configuration of the life management system. First
As shown in the figure, this embodiment is roughly divided into a combustion time accumulating unit 1, a start / stop number accumulating unit 2, a life consumption calculating unit 3, and a life span of gas turbines on all shafts. An information processing unit 4 that manages is provided.

A flame detector ON signal 101 is input to the combustion time accumulator 1, and the combustion time is accumulated while the signal 101 is input.

Each time the gas turbine shaft is stopped, the contact closing signal 102 is input to the start / stop number accumulating unit 2 to accumulate the number of start / stop times. In this case, the counting method is divided into about three types depending on the difference in the life consumption degree. For example, a normal stop contact is counted as one time, whereas a thermally severed stop contact such as an emergency stop is counted as three times by the start / stop number accumulating unit 2.

The combustion time integration unit 1 and the start / stop times integration unit 2 output the combustion time integrated value signal 103 and the start / stop
The number-of-stops integration signal 104 is output, and these signals 103 and 104 are input to the life consumption calculator 3 and the information processor 4. The operation of the life consumption calculator 3 will be described later.

In the information processing unit 4, the life of each component of the gas turbine of each shaft is stored and managed. Then, an alarm output to the alarm window 5 for notifying the inspection time, a consumption output to the recorder 6, or a display output of the life consumption status to the CRT display 7 are performed. Also, check schedule or start-up
The life consumption calculation results and the like of each component of each axis necessary for selecting the stop axis are sent to the computer system 8 for automation. Output signals to the automation computer 8 include a relative value signal 105 of life consumption for each axis and each component, a difference signal 106 of life consumption,
It includes an inspection instruction output signal 107, a start / stop count signal 108 for each axis, an integrated value signal 109 of the combustion time of each axis, and the like.

Here, the contents of calculations performed by the life consumption calculator 3 will be described with reference to FIG.

In FIG. 2, the horizontal axis indicates the number of start / stop times, and the vertical axis indicates the combustion time. A solid line c in FIG. 2 is an example of a life control curve of the gas turbine, and is represented by a linear function y + a logx = K of a logarithmic value of the integrated value y of the burning time and the number of times of starting and stopping x. In this equation, a and K are constants uniquely determined by the type of the gas turbine and the components for managing the life.

 The relative value of the lifetime consumption is given by K in FIG.

For example, assuming that the current combustion time integrated value of the No. 1 axis gas turbine is y _A and the integrated number of start / stop times is x _A , y _A and logx _A
The point A is obtained, and the relative value K _A of the life consumption is obtained from y _A + a logx _A = K _A.

Similarly, the No.2 axis than _{y B + a logx B = K} B, the K _B obtained.

In the example of FIG. 2, the point B is closer to the inspection curve (y + a lo
gx = K), which consumes a lot of life.
o.2 relative comparison of the life of the shaft of the gas turbine is possible by comparing the K _A and K _B. That is, since K _B > K _A , the life of the No. 2 axis is more consumed, and the quantitative difference is given by K _B −K _A.

Although FIG. 1 shows an example of two gas turbines, one unit is actually composed of several gas turbines, and the inspection curve (in the example of FIG. 2, y
(A curve of + a logx = K) is different between the combustor liner and the transition piece, so that much information is given to the information processing section 4.

The above calculation result is used as the life consumption calculation value signal 110,
It is output from the life expenditure calculation unit 13 to the information processing unit 4 and the above-described processing is performed.

According to the above-described embodiment, the relative value of the life consumption of the high-temperature portion such as a combustor liner for each gas turbine can be accurately determined by a signal such as a combustion time indicating the operation history which is a measure of life consumption and the number of times of start / stop. In addition, it can automatically calculate, record, and display the output to the operator.

In addition, by outputting a relative value signal of the life consumption to the computer for automation, etc., the signal also serves as a guideline for selecting the starting and stopping axis of the gas turbine due to the load change, and is used in predicting the periodic inspection time. To obtain useful information.

In the above-described embodiment, the combustion time and the number of times of starting and stopping are used for calculating the life consumption, but it is also possible to use a more quantitative element. For example, the fuel consumption and the combustion temperature can be used, and if an evaluation curve using the turbine inlet temperature or the like can be obtained, it may be used.

Further, in the above embodiment, two parts, the combustor liner and the transition piece, are mentioned as the parts for managing the life, but the present invention can also be applied to the management of hot gas paths such as nozzles and blades of a turbine.

〔The invention's effect〕

As described above, according to the present invention, the conditions of particularly severe combined cycle power generation, and also accurately and automatically calculate, record, and monitor the degree of life consumption of high-temperature components of gas turbines, which are important equipment. By doing
It is possible to prevent a major accident caused by the end of life from occurring.

Further, according to the present invention, by simultaneously and continuously monitoring the lives of a plurality of gas turbines constituting the combined cycle power generation unit, it is possible to make a relative comparison of the degrees of life consumption. Further, for one gas turbine, a state for knowing the regular inspection time is obtained. From such information, a lot of important data on operation as a unit, such as determining a start / stop axis at the time of a load change and drafting a regular inspection schedule, can be obtained.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an embodiment of the present invention, FIG. 2 is a diagram showing life consumption calculation contents according to the above embodiment, and FIG. 3 is an example of a life management curve of a conventional general gas turbine high-temperature component. FIG. 1 combustion time accumulator, 2 start / stop frequency accumulator,
3. Life expenditure calculation section, 4 ... Information processing section.

Claims (1)

(57) [Claims] 1. A combustion time integrating section for taking in combustion time data from a plurality of gas turbine shafts to be monitored and integrating them at any time, and taking in data of the number of start / stop of each gas turbine shaft as needed to accumulate the data. The start / stop number accumulating unit that performs the operation, and supports the constituent materials of high-temperature parts based on the combustion time integrated product value and the start / stop number integrated value output from the combustion time accumulator and the start / stop number accumulator, respectively. The life consumption calculation unit that calculates the life consumption relative value to be compared with the life consumption relative value calculated by the life consumption calculation unit, and determines whether or not the inspection time set in advance for each gas turbine shaft has been reached. An information processing unit for automatically performing display and alarm generation and other information processing,
In the life consumption calculation unit, when the combustion time integrated value is y and the start / stop count is x, the life consumption relative value K
Is calculated as y + log = K.