JPH1130488A - Condenser hotwell level control device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To maintain a hot well water level at a desirable water level at which a plant does not stop operation even when hot well water level control by a common control valve becomes malfunctioning. SOLUTION: A hot well water level of a condenser 2 is detected by a water level detector 8 and inputted to a water level controller 9 as a detected water level signal. Standard water level for water level controller 9 (set value)
Is calculated, and based on this, the first control valve 1
An opening command signal is output to 0 and the second control valve 14.
Even if the operation of the first control valve 10 becomes malfunctioning due to, for example, a stick of the valve shaft, the second control valve 14 functions normally,
The hotwell level is maintained at the desired level.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a geothermal power plant, and more particularly to a hot well water level control device for a condenser which is used in addition to a condenser to maintain a constant circulating water level in a hot well.

[0002]

2. Description of the Related Art Generally, in a geothermal power plant, a direct contact condenser is used as a condenser for condensing turbine exhaust gas. That is, here, the turbine exhaust and the cooling water as the cooling medium directly contact each other without passing through the fixed heat transfer wall, and the cooled steam condenses into condensate, which is collected together with the cooling water in the hot well of the condenser. Will be. There is water as cooling water in addition to condensed condensate in the hot well, and the condensate water level in the hot well fluctuates greatly due to the large amount of cooling water.

A typical example of a circulating water system of a condenser and a hot well water level control will be described with reference to the drawings. In FIG. 5, the steam that has completed expansion in the turbine 1 flows into the condenser 2 as exhaust gas, and the cooling water (hereinafter, referred to as cooling water) from a cooling tower described below.
(Referred to as circulating water) and falls back into the hot well with circulating water as condensate. The high-temperature circulating water is extracted by the circulating water pump 3, and guided to the cooling tower 6 through the return circulating water pipe 4 and each branch pipe 5. Here, the circulating water is cooled by the cold atmosphere and falls into the lower reservoir. The low-temperature circulating water is guided to the condenser 2 through the supply circulating water pipe 7, blows into the exhaust gas flowing in the vessel, and is cooled.

On the other hand, the hot well water level of the condenser 2 is detected by a water level detector 8 and inputted to a water level controller 9 as a detected water level signal. The water level controller 9 calculates a deviation from the standard water level (set value). For example, when the detected water level signal is larger than the set value, the control valve 1 of the path of the circulating water pipe 4 is operated.
When the detected water level signal is smaller than the set value, the opening command signal is output so as to close the control valve 10 so as to open 0. In the figure, reference numeral 11 denotes a circulating water spray valve, which is provided for spraying circulating water into the cooling tower 6. Reference numeral 12 denotes a circulating water stop valve for stopping the flow of circulating water.

[0005]

The hot well water level of the condenser 2 fluctuates drastically due to the large amount of circulating water introduced into the condenser 2, and the control of the hot well water level is particularly poor for some reason. When falling, the amount of circulating water flowing out of the hot well decreases, the hot well water level rises sharply,
It reaches the exhaust chamber of the turbine 1 in several tens of seconds, and there is a risk that the blades of the turbine 1 may come into contact with the circulating water. On the other hand, if the amount of circulating water flowing out of the hot well increases, the circulating water pump 3 will experience an abnormal drop in water level within several tens of seconds.

[0006] Most of the malfunctions of the hot well water level control are caused by some abnormality in the operation of the control valve 10 for adjusting the amount of circulating water, and even if the operation of the control valve 10 is abnormal, There is a need to support this by other means.

Therefore, an object of the present invention is to provide a condenser capable of maintaining the hot well water level at a desirable water level at which the plant does not shut down even when the control of the hot well water level by the ordinary control valve is malfunctioned. It is to provide a hot well water level control device.

[0008]

To achieve the above object, the invention according to claim 1 comprises a first control valve for controlling the amount of circulating water guided from a condenser to a cooling tower, and a hot well water level of the condenser. A water level detector for detecting the water level and a first value based on a deviation between a predetermined set value and a detected water level signal from the water level detector.
A condenser water level controller for producing an opening command signal for determining an opening degree of a control valve, wherein a circulating water amount guided to the cooling tower from the condenser hot well is set to a first value. It is provided with the 1st control valve adjusted in cooperation with the 1st control valve in the course parallel to the control valve.

In the hot well water level control device having the above-mentioned configuration, even when the first control valve is malfunctioned for some reason, the second control valve is used instead to maintain the hot well water level at the desired water level. Adjust
As a result, the hot well water level does not rise to a high water level at which an alarm is output or does not drop to a low water level, and the plant can be continuously operated without being forced to shut down.

Further, the invention according to claim 2 is characterized in that a first control valve for adjusting the amount of circulating water guided from the condenser to the cooling tower, and a water level detector for detecting a hot well water level of the condenser are predetermined. A water level controller for generating an opening command signal for determining an opening of the first control valve based on a deviation between the set value and a detected water level signal from a water level detector. In the device, an emergency control valve that independently controls the amount of circulating water guided from the condenser hot well to the cooling tower instead of the first control valve, a predetermined set value and a detected water level signal from a water level detector, An emergency water level controller that generates an opening command signal that determines the opening of the emergency control valve based on the deviation of the emergency control valve, and when an abnormality occurs in the operation of the first control valve, hot water level control is performed from the water level controller. Means for switching to a water level controller It is characterized in further comprising.

[0011] In the hot well control device having the above-mentioned configuration, even when the first control valve malfunctions for some reason, the emergency control valve takes the place of the emergency control valve to maintain the hot well water level at the desired water level. Adjust. As a result, the hot well water level does not rise to the high water level at which the alarm is output or does not drop to the low water level, and the plant can continue to operate without being forced to shut down.

The invention according to claim 3 is characterized in that a first control valve for adjusting the amount of circulating water guided from the condenser to the cooling tower, and a water level detector for detecting a hot well water level of the condenser are predetermined. A water level controller for generating an opening command signal for determining an opening of the first control valve based on a deviation between the set value and a detected water level signal from a water level detector. In the device, an emergency control valve for adjusting the amount of circulating water guided from the cooling tower to the condenser, and an emergency control valve based on a deviation between a predetermined set value and a detected water level signal from the water level detector. An emergency water level controller for generating an opening command signal for determining an opening degree, and means for switching hot water level control from the water level controller to the emergency water level controller when an abnormality occurs in the operation of the first control valve. It is characterized by the following.

In the hot well water level control device having the above-mentioned structure, even when the first control valve malfunctions for some reason, the emergency control valve takes the place of the emergency control valve to maintain the hot well water level at the desired water level. Adjust As a result, the hot well water level does not rise to a high water level at which an alarm is output or does not drop to a low water level, and the plant can be continuously operated without being forced to shut down.

Further, the invention according to claim 4 is characterized in that a first control valve for adjusting the amount of circulating water guided from the condenser to the cooling tower, and a water level detector for detecting a hot well water level of the condenser are predetermined. A water level controller for generating an opening command signal for determining an opening of the first control valve based on a deviation between the set value and a detected water level signal from a water level detector. In the apparatus, a plurality of circulating water spray valves for spraying circulating water guided from a hot well of the condenser into the cooling tower through independent paths, a predetermined set value and a detected water level signal from a water level detector The number of circulating water spray valves to be operated is determined based on the deviation of the circulating water spray valves, and a circulating water spray valve controller that outputs an opening signal to open the determined number of circulating water spray valves; An error occurs in operation When, it is characterized in further comprising a means for switching the circulating water spray valve controller the hot well water control from the level controller.

In the hot-well water level control device having the above-mentioned structure, even when the first control valve malfunctions for some reason, a plurality of circulating water spray valves instead maintain the water level of the hot well at a desired water level. Adjust the amount of circulating water as follows. As a result, the hotwell water level does not rise to the high water level at which the alarm is output or does not drop to the low water level, and the plant can continue to operate without being forced to shut down.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1, a circulating water pipe 4 is provided with a bypass pipe 13 that bypasses a control valve (hereinafter, referred to as a first control valve) 10, and a second control valve 14 is provided in this path. A second cooperating with the first control valve 10
The control valve 14 is connected to the water level controller 9, and detects a detected water level signal,
The opening changes according to the deviation from the set value, and the bypass pipe 13
The amount of circulating water flowing on the side is adjusted.

This embodiment has the above-described configuration, and the opening command signal from the water level controller 9 is output to both the first control valve 10 and the second control valve 14 during the operation of the condenser 2. At this time, the opening of the first control valve 10 and the second control valve 14 changes according to the opening command signal, and the amount of circulating water passing through the circulating water pipe 4 and the bypass pipe 13 is adjusted.

That is, the first and second control valves 10, 1
While both 4 are functioning normally, the circulating water volume is always maintained properly, so that the water level in the hot well remains at the standard water level.

On the other hand, during the operation of the condenser 2, for example, a stick occurs at the valve shaft of the first control valve 10, and the operation of the first control valve 10 falls into a malfunction. For example, a relatively small amount of circulating water is fixed at an opening at which it flows, and the amount of circulating water extracted from the hot well decreases. At this time, even if the operation of the first control valve 10 becomes malfunctioning, the second control valve 14 is functioning normally, and the hot well water level is temporarily reduced with a decrease in the flow rate at the first control valve 10. Even if it rises, the opening degree of the second control valve 14 is further opened by the opening degree command signal given from the water level controller 9, and the hot well water level does not rise to the high water level at which an alarm is output. Thus, the condenser 2 can continue to operate.

Further, when a large amount of circulating water is fixed at an opening at which a large amount of circulating water flows at the time of stick generation, the opening of the second control valve 14 is narrowed down even though the hot well water level temporarily drops. Therefore, the hot well water level does not drop to the low water level at which an alarm is output. At this time, no alarm is output, and the condenser 2 can continue to operate.

Thus, in the present embodiment, even when the first control valve 4 malfunctions for some reason, the hot well water level can be maintained at a desired level by the second control valve 14 having the same function. . Thus, the plant can continue to operate without being forced to shut down.

Further, another embodiment of the present invention will be described. In FIG. 2, the circulating water pipe 4 is provided with a bypass pipe 13 which bypasses the first control valve 10, and an emergency control valve 15 for controlling the amount of circulating water flowing in the path is provided therein. In addition, an emergency water level controller 16 is provided which obtains a deviation between a set value similar to that of the water level controller 9 and a detected water level signal from the water level detector 8 to generate an opening degree command signal. The emergency water level controller 16 is connected to the emergency control valve 15 for inputting an opening command signal.

Further, a switch 17 for switching the hot well water level control between the two water level controllers 9 and 16 is provided. The switch 17 has an input terminal connected to the first control valve 1.
When an abnormality such as a stick occurs at the valve shaft of 0, it is connected to an operation abnormality detector 18 which outputs an operation abnormality signal, and the output ends thereof are the water level controller 9 and the emergency water level controller 16.
And are connected respectively.

The present embodiment has the above-described configuration. During operation of the condenser 2, an opening command signal from the water level controller 9 is output to the first control valve 10, and the opening is used as the opening command signal. The amount of circulating water passing through the circulating water pipe 4 changes accordingly. That is, while the first control valve 10 is functioning normally, the amount of circulating water is always properly maintained, so that the water level in the hot well maintains the standard water level.

On the other hand, during operation of the condenser 2, for example, a stick occurs at the valve shaft of the first control valve 10, and the first control valve 10
When the operation of the device becomes malfunctioning, the operation abnormality detector 18 detects this abnormality. This abnormal operation signal is transmitted to the switch 17, and the switch 17 outputs a switching signal to open the water level controller 9 and simultaneously close the emergency water level controller 16.

The emergency water level controller 16 receives the detected water level signal from the water level detector 8, and calculates the deviation between the set value and the detected water level signal. Is output. Therefore, the emergency control valve 15 is opened, and the emergency control valve 15 adjusts the amount of circulating water passing through the bypass pipe 13 instead of the first control valve 10 that has been adjusting the amount of circulating water.

When a stick is generated at the first control valve 10, for example, when the opening amount at which a relatively small amount of circulating water flows is fixed, the hot well water level temporarily rises. Since it opens widely, the amount of circulating water to the cooling tower 6 is secured without decreasing, the hot well water level does not rise to a high water level, and no alarm is output. Thus, the condenser 2 can continue to operate.

When a relatively large amount of circulating water is fixed at an opening at which a relatively large amount of circulating water flows at the time of stick generation, the emergency control valve 1 is initially provided although the hot well water level temporarily drops.
5 is slightly opened, and then the opening is gradually increased in accordance with the deviation, so that the hot well water level does not drop to the low water level, and no alarm is output at this time.

As described above, also in the present embodiment, the first
Even when the control valve 4 is malfunctioning for some reason, the emergency control valve 15 having the same function can keep the hot well water level at a desired water level. Therefore, the plant can be continuously operated without being forced to shut down.

Next, another embodiment of the present invention will be described. In FIG. 3, an emergency control valve 19 for adjusting the amount of circulating water flowing in the circulating water pipe 7 for supply is provided. Further, an emergency water level controller 20 is provided which calculates a deviation between a set value similar to that of the water level controller 9 and a detected water level signal from the water level detector 8 to generate an opening degree command signal. It is connected to an emergency control valve 19 for inputting a degree command signal. Further, a switch 21 for switching the hot well water level control between the two water level controllers 9 and 20
Is provided. The switch 21 has an input end connected to an operation abnormality detector 18 that outputs an operation abnormality signal when an abnormality such as a stick occurs at the valve shaft of the first control valve 10, and has an output end connected to the water level controller 9. And the emergency water level controller 20.

The present embodiment has the above-described configuration. During operation of the condenser 2, an opening command signal from the water level controller 9 is output to the first control valve 10, and the opening is used as the opening command signal. The amount of circulating water passing through the circulating water pipe 4 changes accordingly. That is, while the first control valve 10 is functioning normally, the amount of circulating water is always properly maintained, so that the water level in the hot well maintains the standard water level. During the circulation of the circulating water, the opening degree of the circulating water stop valve 12 of the supply circulating water pipe 7 is kept fully open by a signal from a control device (not shown).

On the other hand, during operation of the condenser 2, for example, when a stick is generated at the valve shaft of the first control valve 10, and the operation of the first control valve 10 becomes malfunctioning, the operation abnormality detector 18 detects this abnormality. To detect. This abnormal operation signal is transmitted to the switch 21.
To the water level controller 9 from the switch 21,
At the same time, a switching signal is output so that the emergency water level controller 20 is closed.

The detected water level signal from the water level detector 8 is input to the emergency water level controller 20, where the deviation between the set value and the detected water level signal is calculated. Here, an opening command signal is generated based on the obtained deviation, and is output to the emergency control valve 19. Therefore, the emergency control valve 19 is opened, and the emergency control valve 19 adjusts the amount of circulating water flowing into the condenser 2 instead of the first control valve 10 which has been adjusting the amount of circulating water.

When a stick occurs at the first control valve 10,
For example, when a relatively small amount of circulating water is fixed at an opening at which it flows, the hot well water level rises temporarily, but the emergency control valve 19 opens greatly, so that the amount of circulating water to the cooling tower 6 does not decrease. The hot well water level does not rise to the high water level and no alarm is output. Thus, the condenser 2 can continue to operate.

If a relatively large amount of circulating water is fixed at an opening at which a relatively large amount of circulating water flows at the time of stick generation, the emergency control valve 1 is initially provided although the hot well water level temporarily drops.
Since the opening 9 is slightly opened and then gradually increased according to the deviation, the hot well water level does not drop to the low water level, and no alarm is output at this time.

As described above, also in the present embodiment, the first
When the control valve 10 is malfunctioning for some reason,
The emergency control valve 19 having the same function can keep the hot well water level at a desired water level. Therefore, the plant is not forced to shut down and can continue to operate.

Further, an embodiment different from the above embodiment will be described. In FIG. 4, the hot well water level control device has a circulating water spray valve controller 22 for controlling the number of operating circulating water spray valves 11 for spraying circulating water. The circulating water spray valve control device 22 includes a set value and a water level detector 8.
Calculates the deviation from the detected water level signal, determines the number of circulating water spray valves 11 to be operated, and creates an opening signal for the circulating water spray valves 11 corresponding to the number. Connected to valve 11. Also,
The circulating water spray valve controller 22 includes an opening setting device that adjusts the opening of the circulating water stop valve 12 of the circulating water pipe 7 to a predetermined opening.

Further, a switch 23 for switching the hot well water level control between the water level controller 9 and the circulating water spray valve controller 22 is provided. The switch 23 has an input terminal connected to the operation abnormality detector 18 that outputs an operation abnormality signal when an abnormality such as a stick occurs at the valve shaft of the first control valve 10, and has an output terminal connected to the water level controller 9. And the circulating water spray valve control device 22.

The present embodiment has the above-described configuration. During the operation of the condenser 2, an opening command signal from the water level controller 9 is output to the first control valve 10, and the opening is used as the opening command signal. The amount of circulating water passing through the circulating water pipe 4 changes accordingly. That is, while the first control valve 10 is functioning normally, the amount of circulating water is always properly maintained, so that the water level in the hot well maintains the standard water level.

On the other hand, during the operation of the condenser 2, for example, a stick occurs at the valve shaft of the first control valve 10, and the first control valve 10
When the operation of the device becomes malfunctioning, the operation abnormality detector 18 detects this abnormality. This abnormal operation signal is sent to the switch 23, and the switch 23 outputs a switching signal to close the water level controller 9 and at the same time to close the circulating water spray valve controller 22.

When the circulating water spray valve controller 22 starts up, the opening of the circulating water stop valve 12 is reduced to a predetermined opening from the previous opening by the opening setting device. further,
The deviation between the set value and the detected water level signal is calculated, the number of circulating water spray valves 11 to be operated is determined, and an opening signal for opening the circulating water spray valve 11 is output according to the determined number. For this reason, for example, three circulating water spray valves 11 are opened, and the circulating water spray valve 11 adjusts the amount of circulating water flowing through the return circulating water pipe 4 instead of the first control valve 10.

When a stick occurs at the first control valve 10,
For example, when a relatively small amount of circulating water is fixed at an opening degree at which the circulating water flows, the hot well water level temporarily rises, but since the three circulating water spray valves 11 open simultaneously, the hot well to the cooling tower 6 The circulating water volume is secured without decreasing, the hot well water level does not rise to the high water level, and no alarm is output. Thus, the condenser 2 can continue to operate.

When a relatively large amount of circulating water flows and is fixed at the time of stick generation, the hot-well water level temporarily drops, but first, one circulating water spray valve 11 is opened and the deviation is reduced. When the value approaches zero, the second circulating water spray valve 11 opens, so that the hot well water level does not drop to the low water level, and no alarm is output at this time.

As described above, even in the present embodiment, even if the first control valve 10 malfunctions for some reason, the circulating water spray valve 11 which is opened by the number corresponding to the hot well water level sets the desired hot well water level. Can be kept. Therefore, the plant can be continuously operated without being stopped.

[0045]

As described above, according to the present invention, even when the hot well water level control by the ordinary control valve is in trouble,
The second control valve, or emergency control valve or multiple circulating water spray valves, regulates the amount of circulating water, so that the hot well level does not rise to a high level where an alarm is output, or drops to a low level. Without this, the plant can be operated continuously.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a hot well water level control device of a condenser according to the present invention.

FIG. 2 is a configuration diagram showing another embodiment of the present invention.

FIG. 3 is a configuration diagram showing another embodiment of the present invention.

FIG. 4 is a configuration diagram showing another embodiment of the present invention.

FIG. 5 is a configuration diagram showing a conventional hot well water level control device.

[Explanation of symbols]

 2 condenser 6 cooling tower 8 water level detector 9 water level controller 10 first control valve 14 second control valve 15,19 emergency control valve 16,20 emergency water level controller 17,21,23 switch

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toshiyuki Takahashi 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Corporation Head Office

Claims (4)

[Claims] 1. A first control valve for controlling an amount of circulating water guided from a condenser to a cooling tower, a water level detector for detecting a hot well water level of the condenser, a predetermined set value and the water level A water level controller for generating an opening command signal for determining an opening of the first control valve based on a deviation from a detected water level signal from the detector; A first control valve for adjusting the amount of circulating water guided from the hot well of the condenser to the cooling tower in a path parallel to the first control valve in cooperation with the first control valve; A hot water level control device for a condenser, wherein the circulating water amount is adjusted by the normally functioning second control valve when an abnormality occurs in the operation of (1). 2. A first control valve for adjusting an amount of circulating water guided from a condenser to a cooling tower, a water level detector for detecting a hot well water level of the condenser, a predetermined set value and the water level A water level controller for generating an opening command signal for determining an opening of the first control valve based on a deviation from a detected water level signal from the detector; An emergency control valve that independently controls the amount of circulating water guided from the condenser hot well to the cooling tower instead of the first control valve, a predetermined set value and a detected water level signal from the water level detector; An emergency water level controller for generating an opening command signal for determining the opening of the emergency control valve based on the deviation of the emergency control valve, and when an abnormality occurs in the operation of the first control valve, the hot well water level control is performed by the water level adjustment. Meter to the emergency water level controller A hot well water level control device for a condenser. 3. A first control valve for adjusting an amount of circulating water guided from a condenser to a cooling tower, a water level detector for detecting a hot well water level of the condenser, a predetermined set value and the water level. A water level controller for generating an opening command signal for determining an opening of the first control valve based on a deviation from a detected water level signal from the detector; An emergency control valve for adjusting the amount of circulating water guided from the cooling tower to the condenser; and opening of the emergency control valve based on a deviation between a predetermined set value and a detected water level signal from the water level detector. An emergency water level controller for generating an opening command signal for determining a degree, and a means for switching hot well water level control from the water level controller to the emergency water level controller when an abnormality occurs in the operation of the first control valve. A reversal characterized by comprising Hot water level control device for water heater. 4. A first control valve for controlling an amount of circulating water guided from a condenser to a cooling tower, a water level detector for detecting a hot well water level of the condenser, a predetermined set value and the water level. A water level controller for generating an opening command signal for determining an opening of the first control valve based on a deviation from a detected water level signal from the detector; A plurality of circulating water spray valves for spraying circulating water guided from the hot well of the condenser into the cooling tower through independent paths, a predetermined set value and a detected water level signal from the water level detector, A circulating water spray valve controller for determining the number of the circulating water spray valves to be operated based on the deviation of the circulating water spray valve, and outputting an opening signal to open the determined number of the circulating water spray valves; Abnormal valve operation Means for switching hot water level control from the water level controller to the circulating water spray valve controller when it occurs.