JPH10231739A - Gas turbine combustion monitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the malfunction of a combustion monitor, caused by the abnormal temperature signal of an exhaust gas temperature detector, by detecting rapidly occurrence of the abnormality of the exhaust gas temperature detector by a gas turbine with the combustion monitor by which the conditions of a combustor is caught by a combustor downstream side exhaust gas temperature. SOLUTION: The monitoring of the combustion states of this gas turbine combustion monitor 15 and the detection of the abnormality of exhaust gas temperature detectors 13, are performed in a manner that a quantity of state computing element obtains from the minimum value to the maximum value of a temperature signal 14 obtained by a plurality of exhaust gas temperature detectors 13 arranged in a combustor downstream side exhausting part 12, a deviation computing element calculates from a first level quantity of state deviation to an (m) level property deviation, and a comparator finds out comparison with a deviation allowable value.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a gas turbine combustion monitoring device.

[0002]

2. Description of the Related Art Conventionally, this type of method detects an abnormality in a detector by detecting an abnormality in a detector output level, that is, an excessive level, an excessive level, or a low level.
Alternatively, a method is known in which the output change rate is determined to be abnormal, that is, the change rate is excessive. However, these methods
As the operating range of state variables expands as the temperature and pressure of gas turbine combustors increase and the operating range becomes wider, the state variable detector has an output level in the event of an abnormality that is common to all operating ranges. , It is difficult to determine the output change rate.

[0003] Further, when the occurrence of an abnormality in the detector does not appear instantaneously in the change of the output value, but the output gradually changes with the passage of time, the output level at the time of the above-mentioned abnormality is detected.
The determination based on the output change rate is difficult to determine.

[0004]

The abnormality of the detector of the gas turbine combustion monitoring device is determined by the output level or the output change rate when the output of the detector is abnormal. However, there is a problem that it is difficult to determine the criterion based on the output level at the time of abnormality or the output change rate due to the output delay of the abnormal output.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent an abnormality in a detector output due to a detector abnormality from causing an erroneous determination of a gas turbine combustion monitoring device.

[0006]

According to the present invention, there is provided a gas turbine combustion monitoring apparatus comprising: a gas turbine having a plurality of (k) combustors; In, the output of the state quantity detector installed on the downstream side of the combustor with respect to the combustor alone is necessary for affecting the output of a plurality of (m) detectors centering on the corresponding combustor position. Number (n
(2) If all the state quantity detectors are normal, if there is abnormal combustion, a plurality (m
Output fluctuations in the range of As a result, assuming that the deviations of the detector outputs are the first-order detector output deviation, the second-order detector output deviation... From the largest order, the m-th state detector output deviation exceeds the deviation allowable value.

(3) Conversely, if one detector is abnormal,
During normal combustion, output fluctuation occurs in one of the detector outputs. In this case, as for the detector output deviation, only the first place exceeds the deviation allowable value.

(4) From the above, from the influence range of the combustion state,
When the number of deviations of the detector output exceeding the deviation allowable value is less than m, it can be determined that one detector is abnormal. Further, in the conventional method, the abnormal level of the detector is determined from the abnormal value of the output change of the detector itself. However, according to the present method, the abnormal level can be determined by the same method as the abnormality determination method for the combustion state.

(5) Further, by adding a number to each of the detectors, the output fluctuation position is limited, and the abnormality detector position is clarified.

[0010] For the combustor alone, the necessary number is set so that the output of the state variable detector installed on the downstream side of the combustor affects the output of a plurality of detectors centering on the corresponding combustor position. When a detector abnormality occurs in a gas turbine, the detector output fluctuates only at the corresponding detector position, and the detector output deviation is small unlike that during abnormal combustion. A combustion monitoring device for a gas turbine that can be distinguished and determined can be realized.

[0011] This makes it possible to improve the determination accuracy of the gas turbine combustion monitoring device, to prevent unnecessary operation of the gas turbine due to erroneous determination, and to operate the gas turbine efficiently.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) Details of the present invention will be described based on an embodiment shown below. FIG. 1 shows a configuration of a gas turbine power generation facility as an example for realizing the present invention, and a configuration of a combustion monitoring device for a gas turbine as an example for implementing the present invention. FIG. 2 is a side view of the gas turbine power generation equipment shown in FIG.
FIG. 3 is a side view taken along line BB of FIG. 1.

The gas turbine power generation equipment includes a compressor 1, a gas turbine 2, a combustor 3, and a power generator 4. The compressed air 5 compressed by the compressor 1 is guided to a plurality of combustors 3 as shown in FIG. 2, and the fuel 6 controls a fuel control valve 9 by a control command signal 8 from a gas turbine controller 7. To the combustor 3.

After the combustion air 10 burned in the combustor 3 works in the gas turbine 2, it becomes exhaust gas 11 and is guided to the exhaust part 12. The exhaust part 12 is provided with an exhaust gas temperature detector 13 for measuring the temperature of the exhaust gas 11 to monitor the combustion state of the plurality of combustors 3. As shown in FIG. 3, a plurality of exhaust gas temperature detectors 13 are provided in the circumferential direction of the exhaust unit 12.

The temperature signal 14 of the exhaust gas 11 measured by the exhaust unit 12 is input to a gas turbine combustion monitoring device 15 to determine abnormal combustion and abnormality of the exhaust gas temperature detector 13,
In the case of abnormal combustion, an abnormal combustion signal 16 is output to the gas turbine protection device 17, and in the case of an abnormality of the exhaust gas temperature detector 13, a detector abnormality signal 18 is output to the gas turbine control device 7.
Output to

During abnormal combustion, the gas turbine protection device 17
Then, the gas turbine stop command signal 19 is output to the fuel control valve 9 to stop the operation. When the detector is abnormal, the gas turbine controller outputs the control command signal 8 to the fuel control valve 9 to continue the operation state. I do.

FIG. 4 shows a block diagram of the gas turbine combustion monitoring device 15.

The gas turbine of the present invention shown in FIG.
As shown in (1), there are a plurality of (k) combustors 3, and the output of the exhaust gas temperature detector 13 installed in the exhaust unit 12 on the downstream side of the combustor 3 corresponds to each combustor 3. When the number (n) required to affect the output of a plurality (m) of detectors around the position of the combustor is set in the circumferential direction of the exhaust unit 12 as shown in FIG. FIG. 5 shows the output behavior of the exhaust gas temperature detector 13 during combustion and abnormal combustion. FIG. 6 shows a case where an abnormality of the exhaust gas temperature detector 13 occurs during normal combustion of the gas turbine.

In a gas turbine provided with k (k ≧ 1) combustors 3, the influence of the combustion state on each of the combustors depends on the number of exhaust gases installed in the exhaust unit 12 on the downstream side of the combustor. The gas temperature detector 13 outputs m (m> 1) temperature signals 14
A combustion abnormality monitoring method when it appears as a fluctuation in
An abnormality detection method for the p (1 ≦ p ≦ m−1) exhaust gas temperature detectors 13 will be described.

[0020] n is installed in the exhaust part 12 on the downstream side of the combustor.
The temperature signals 14 of the exhaust gas temperature detectors 13 are input to the state quantity calculator 20, and the exhaust gas temperature deviations calculated by the deviation calculator 21 are sorted into the first state quantity deviation 2 in descending order of the deviation.
2, second-order state quantity deviation 23, ..., m-th-order state quantity deviation 24
Ask for. The exhaust gas temperature detector 13 is provided such that the temperature signal 14 goes to the extreme of either the rising side or the falling side when the detector is abnormal.

Here, an example is shown in which the temperature signal 14 goes to the lower limit when the exhaust gas temperature detector 13 is abnormal. When the change direction of the temperature signal 14 is on the falling side when the exhaust gas temperature detector 13 is abnormal, the minimum value 2 of the temperature signal 14
The deviation from the maximum value 26 is calculated in ascending order from 5, and the first state quantity deviations 22, 2 are calculated from the deviation between the minimum value 25 and the maximum value 26.
The second state quantity deviation 23 is calculated from the difference between the smallest value 27 and the maximum value 26, and the m-th state quantity deviation is calculated from the difference between the m-th smallest value 28. The state quantity deviation signal value obtained by the deviation calculator 21 is converted by the comparator 29 into the state quantity deviation allowable value 3
Compared to zero. The method of determining the state quantity deviation allowable value 30 is as follows.
The state quantity deviation is determined from a value that can determine whether the combustion state is normal / abnormal. According to the output deviation characteristic of the exhaust gas temperature detector 13 affected by the combustion state of the combustor 3 in which the combustion abnormality has occurred as shown in FIG.
<Α ≦ 1) The detection accuracy can be improved by multiplying by 31.

At this time, when the combustion state is normal and the exhaust gas temperature detectors 13 are all normal, the state quantity deviation signal values are all less than the deviation allowable value 30. For this reason,
Since all of the first state quantity deviation 22 and the second state quantity deviation 23 to the m-th state quantity deviation 24 are smaller than the deviation allowable value 30, the following is obtained.
0 or more ”is not satisfied, and the condition 33 that“ the second-order state quantity deviation 23 is equal to or more than the allowable deviation 30 ”is not satisfied. Therefore, the logical product 34 of these two conditions is satisfied. However, the combustion state is determined to be normal.
Further, in this case, since the condition 32 that the “first-order state quantity deviation 22 is equal to or more than the deviation allowable value 30” is not satisfied, the logical product 38 is not satisfied and the exhaust gas temperature detector 13 is abnormal. No judgment is issued.

When the combustion state is normal and the exhaust gas temperature detector 13 among the exhaust gas temperature detectors 13 is abnormal, the detector output 14 is determined due to the abnormality of the detector.
Moves to the extreme value on the descending side, the condition 32 that “the first state quantity deviation 22 is equal to or more than the deviation allowable value 30” is satisfied, but the second state quantity deviation 2 is satisfied because the combustion state is normal.
Since everything from 3 to the m-th state quantity deviation 24 is smaller than the deviation allowable value 30, the condition 33 that “the second state quantity deviation 23 is greater than or equal to the deviation allowable value 30” is not satisfied. The product 34 is not established, and it is not determined that the combustion is abnormal. However, in this case, since everything from the second state quantity deviation 23 to the m-th state quantity deviation 24 is less than the deviation allowable value 30, the logical sum 37 of the negative 36 of each condition is established,
The logical product 38 with the condition 32 is established. After the timer 39 confirms that the condition 38 has been satisfied for the specified time or more, it is determined that the exhaust gas temperature detector 13 is abnormal.

However, when there are two or more abnormal exhaust gas temperature detectors 14, even if the combustion state is normal combustion, the condition 32 that "the first state quantity deviation 22 is equal to or more than the allowable deviation value 30" is satisfied. And the condition 33 that “the second state quantity deviation 23 is equal to or larger than the deviation allowable value 30” is satisfied.
The exhaust gas temperature detector 13 determined to be abnormal in order to avoid the determination of abnormal combustion from a malfunction due to this signal
The number is fed back to the state quantity calculator 20 as the abnormality determination signal 40, and the satisfaction of the conditions 32 and 33 is canceled by excluding the temperature signal 14 from the calculation. However,
The timer 35 considers the calculation delay with respect to the timer 39 so that the abnormal combustion determination is established after the removal of the temperature signal 14 of the abnormal exhaust gas temperature detector 13 is completed.

On the other hand, when the combustion state is abnormal combustion and the exhaust gas temperature detectors 13 are all normal, all of the first to m-th state quantity deviations 22 to 24 are:
Since the deviation allowable value is equal to or larger than 30, the condition 32 that “the first-order state variable deviation 22 is equal to or larger than the deviation allowable value 30” is satisfied, and “the second state amount deviation is equal to the deviation allowable value 3”.
Is greater than or equal to 0 ", the logical product 34 of these two conditions also holds. After confirming by the timer 35 that this condition has been satisfied for a specified time or longer, it is determined that the combustion state is abnormal combustion. At this time, since all of the exhaust gas temperature detectors 13 are normal,
All the conditions from the second state quantity deviation 23 to the m-th state quantity deviation 24 are satisfied, the condition of the logical sum 37 of the negation 36 is not satisfied, and no abnormality of the exhaust gas temperature detector 13 is output.

If the combustion state is abnormal combustion, and if the exhaust gas temperature detectors 14 within the exhaust gas temperature detectors 13 are abnormal, the above two or more exhaust gas temperature detectors 14 An abnormal temperature signal 14 similar to the abnormal state of the temperature detector 13 is fed back to the state quantity calculator 20 as an abnormality determination signal 40, and the temperature signal 14 is excluded from the calculation, whereby the abnormality of the exhaust gas temperature detector 13 is determined. After the conditions 32 and 33 are not satisfied, the conditions 32 and 33 are satisfied from the combustion state to determine the combustion state, and it is determined that the combustion is abnormal.

However, in the method of detecting an abnormality of the exhaust gas temperature detector 13 of the gas turbine combustion monitoring device 15 shown in this embodiment, the abnormal number of exhaust gas temperature detectors 13
To a number less than the number that affects the temperature signal 14 (1 ≦ p ≦
m-1). For example, if the total number of combustors is 10
(K = 10), and the exhaust gas temperature detector 13 is affected by three for each combustor (m = 10)
3), the number of the exhaust gas temperature detectors 13 that can tolerate occurrence of an abnormality is from 1 to 2 (1 ≦ p ≦ 3-1). At this time, if the combustion state is normal and three or more (p> m-1) exhaust gas temperature detectors 13 are abnormal, the deviation from the first state quantity deviation 22 to the third state quantity deviation is determined. Allowable value 30
Accordingly, the condition that “the first state quantity deviation 22 is equal to or greater than the deviation allowable value 30” is satisfied, while “one of the second state quantity deviation 23 to the third state quantity deviation” is satisfied. At least is less than the allowable deviation value 30 ", the logical sum 38 of these two conditions is not satisfied, and the exhaust gas temperature detector 13 is abnormal despite the fact that the exhaust gas temperature detector 13 is abnormal. 13 is erroneously determined to be normal.
From the above, when the combustion state is normal, for each combustor,
When the influence of the combustion state appears as fluctuations of m (m> 1) temperature signals 14 by the exhaust gas temperature detectors 13 provided in the exhaust section 12 on the downstream side of the combustor, p (1 ≦ p
≦ m−1) abnormalities of the exhaust gas temperature detectors 13 can be determined, whereby the accuracy of the combustion abnormality determination of the gas turbine combustion monitoring device 15 can be improved.

(Embodiment 2) As another embodiment for realizing the present invention, FIG. 8 is a block diagram showing a judgment method thereof.
In the gas turbine provided with k (k ≧ 1) combustors 3 shown in FIG. 1, for each combustor, n influences of the combustion state are provided in the exhaust unit 12 on the downstream side of the combustor. An exhaust gas temperature detector 13 monitors a combustion abnormality in a case where the temperature fluctuations appear as deviations of m (m> 1) temperature signals 14, and detects r (1 ≦ p <r <p × k) exhaust gas temperatures A method of detecting an abnormality of the device 13 will be described.

As shown in FIG. 7, n of the exhaust gas temperature detector 13 installed in the exhaust part 12 on the downstream side of the gas turbine combustor
Of the exhaust gas temperature detector 13 affected by the combustion state
Each unit is divided into k blocks for each combustor as one block 41.

Each block 26 is considered to be the same as the abnormality detection method of the state quantity detector 20 of the gas turbine combustion monitoring device 17 shown in FIG.
Assuming that the number of the exhaust gas temperature detectors 13 is n = m, the abnormality of the exhaust gas temperature detectors 13 is determined for each block. That is, m exhaust gas temperature detectors 13 in each block
Is input to the state quantity calculator 20, and the state quantity deviations calculated by the deviation calculator 21 are arranged in descending order from the first state quantity deviation 22, the second state quantity deviation 23,. An amount deviation 24 is obtained, and the obtained state amount deviation signal is compared with a deviation allowable value 30 by a comparator 29.

At this time, the combustor 3 corresponding to each block
If the combustion state is normal and the exhaust gas temperature detectors 13 in the block 41 are all normal, the block 41
Are all less than the deviation allowable value 30.
Therefore, all of the block 41 from the first state quantity deviation 22 to the m-th state quantity deviation 28 is smaller than the deviation allowable value 30, so that "the first state quantity deviation 22 is equal to the deviation allowable value 3".
32 is not satisfied, and the logical product 38
Is not established, no abnormality signal of the exhaust gas temperature detector 13 is issued, so that it is determined that the exhaust gas temperature detector 13 of the corresponding block 41 is normal. Further, in this case, since the condition 32 is not satisfied in the determination of the combustion state, the logical product 34 is not satisfied and it is determined that the combustion is normal.

Conversely, the combustor 3 corresponding to each block 41
Is normal, but the number of the exhaust gas temperature detectors 13 in the block 41 is abnormal, the block 2
Among the state quantity deviation signal values in 6, p signals have a deviation allowable value of 30 or more. Since the signal exceeding the deviation allowable value 30 is generated by the exhaust gas temperature detector 13 in which the corresponding block 41 becomes abnormal, the condition 32 that “the first state quantity deviation 22 is equal to or more than the deviation allowable value 30” is set. Is satisfied, and “the second-order state quantity deviation 23 to the m-th state quantity deviation 24
Is less than the allowable deviation value 30 ", the logical sum 37 of 1 ≦ p <m is satisfied, and the logical product 38 of these two conditions is satisfied, and the exhaust gas temperature detector 13
Of the corresponding block 41
It is determined that the exhaust gas temperature detector 13 is abnormal.
In this case, after the timer 39 confirms the continuation of the abnormality of the exhaust gas temperature detector 13, the abnormal exhaust gas temperature
The temperature signal 14 of No. 3 is fed back to the state quantity calculator 20 by the abnormality determination signal 40 and is excluded from the calculation. Therefore, the condition 32 that “the first state quantity deviation 22 is equal to or greater than the deviation allowable value 30” is not satisfied, and the logical product 34 is not satisfied.

On the other hand, when the combustion state is abnormal and the exhaust gas temperature detectors 13 are all normal, all the deviations from the first-order state quantity deviation 22 to the m-th state quantity deviation 24 are equal to the allowable deviation value. Since the logical product 34 of the condition 32 and the condition 33 is satisfied when the value becomes 30 or more, it is determined that the combustion is abnormal, and after the abnormal continuation is confirmed by the timer 35, the occurrence of the abnormal combustion is output to the gas turbine protection device 17. I do. In this case, “the second-order state quantity deviation 23 to the m-th state quantity deviation 2
4 is less than the allowable deviation value 30 ", the exhaust gas temperature detector 13 is determined to be normal.

Conversely, if the combustion state is abnormal and the number of exhaust gas temperature detectors is abnormal in the range from singly to p, the combustion state is abnormal and the exhaust gas temperature detector 13
Are determined to be abnormal combustion, as in the case where all are normal.

That is, in each block 41, the number of abnormalities of the exhaust gas temperature detector 13 at which the abnormality of the exhaust gas temperature detector 13 can be determined is such that one combustor affects the temperature signal 14 of the exhaust gas temperature detector 13. Since it is less than the given number, the number is up to p (1 ≦ p ≦ m−1).

Since it is possible to determine the abnormality of up to p exhaust gas temperature detectors 13 for each block 41, in a gas turbine having k combustors 3, up to k × p exhaust gas blocks The abnormality of the temperature detector 13 can be determined.

As described above, when the combustion state is normal, the combustor 1
The effect of the combustion state on the exhaust unit 1 on the downstream side of the combustor
2 by the exhaust gas temperature detector 13 installed in n
When (m> 1) appear as fluctuations of the temperature signals 14, it is possible to determine the abnormality of the exhaust gas temperature detectors 13 from 1 to p × k. Combustion abnormality determination accuracy can be improved.

[0038]

According to the present invention, in a gas turbine having a gas turbine combustion monitoring device that captures the state of the combustor in the exhaust gas temperature on the downstream side of the combustor, it is possible to quickly detect the occurrence of an abnormality in the exhaust gas temperature detector. , The malfunction of the gas turbine combustion monitoring device due to the abnormal temperature signal of the abnormal exhaust gas temperature detector can be prevented.

[Brief description of the drawings]

FIG. 1 is a block diagram of a gas turbine power generation facility and a gas turbine combustion monitoring device according to an embodiment of the present invention.

FIG. 2 is a front view taken along the line AA of FIG. 1;

FIG. 3 is a front view taken along the line BB of FIG. 1;

FIG. 4 is a block diagram of a gas turbine combustion monitoring device showing one embodiment of the present invention.

FIG. 5 is a characteristic diagram showing a change in a state quantity on a downstream side of a combustor according to a gas turbine combustion state.

FIG. 6 is a characteristic diagram showing a change in state quantity when a state quantity detector on the downstream side of the gas turbine combustor is abnormal.

FIG. 7 is an explanatory diagram of an exhaust gas temperature detector for a state variable detector abnormality determination method of a gas turbine combustion monitoring device according to another embodiment of the present invention.

FIG. 8 is a block diagram of a gas turbine combustion monitoring device according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Compressor, 2 ... Gas turbine, 3 ... Combustor, 4 ... Generator, 5 ... Compressed air, 6 ... Fuel, 7 ... Gas turbine controller, 8 ... Control command signal, 9 ... Fuel control valve, 10 ... Combustion air, 11 exhaust gas, 12 exhaust part, 13 exhaust gas temperature detector, 14 temperature signal, 15 gas turbine combustion monitoring device, 16 abnormal combustion signal, 17 gas turbine protection device, 18 detection , A gas turbine stop command signal.

Claims (1)

[Claims] 1. A combustor to which fuel is supplied via a fuel flow control valve, an air compressor for supplying combustion air to the combustor, and a turbine driven by combustion gas generated in the combustor. In a device for monitoring a combustion state of a gas turbine provided by a combustion gas temperature or a state quantity of an exhaust gas temperature, a plurality of exhaust gas temperature detectors are provided for one combustor to obtain a plurality of detection amounts, A maximum value and a second maximum value of the deviation of the detected amount are calculated, and it is determined whether or not each of the deviation amounts is within a predetermined range of the allowable value of the exhaust gas temperature deviation, and the deviation of the deviation is determined. If both the maximum value and the second maximum value are within the range of the exhaust gas temperature deviation allowable value, it is determined that the combustion is normal, and both the maximum value of the deviation and the second maximum value are the exhaust gas. Within the allowable temperature deviation range. If not, it is judged as abnormal combustion, and only the maximum value of the deviation is not within the range of the allowable value of the exhaust gas temperature deviation,
A combustion monitoring device for a gas turbine, wherein when the second maximum value is within the range of the exhaust gas temperature deviation allowable value, it is determined that the exhaust gas temperature detector is abnormal.