JPS5833361B2 - Turbine operation control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a turbine that can automatically lower the vacuum of a condenser in order to quickly prevent a temporary increase in the pressure between the turbine shaft and the casing. It relates to an operation control device.

In a turbine generator, if the load suddenly decreases or a plant trip occurs during load operation of the turbine, the steam flowing into the condenser will suddenly decrease and the vacuum value of the condenser will increase, causing the low-pressure casing to contract.

However, it takes a certain amount of time for the loaf side to cool down, and as the rotation decreases, the rotor shrinks due to centrifugal force and loosens, so the pressure between the turbine shaft and the casing temporarily increases.

If the pressure of the lid exceeds a certain limit, the steam sealing fins will come into contact with the turbine blades, causing not only vibration but also the risk of destruction of the turbine itself.

In order to avoid this, that is, as a measure to prevent an increase in the cover, it is effective to reduce the vacuum in the condenser, and conventionally this has been done by opening and closing a vacuum breaker valve (manual or electric valve).

However, sudden decreases in turbine load and plant trips occur suddenly, and the vacuum reduction operation of the condenser must be done quickly, but conventional methods cannot meet this requirement. The drawback was that it took time to maintain the vacuum.

In order to eliminate the above-mentioned drawbacks, the present invention provides a turbine operation control device that can automatically perform a vacuum reduction operation of a condenser.

The turbine operation control device of the present invention includes a first detection device that is provided in communication with the inside of the condenser and detects the vacuum value of the condenser, and a vacuum pressure control valve that is provided in communication with the condenser. and a second detection device installed inside the turbine that detects the lid between the turbine shaft and the casing, and control for controlling the vacuum pressure control valve by comparing the operation commands of the first and second detection devices. It is characterized by comprising a device.

Hereinafter, the present invention will be described in detail based on an illustrated embodiment.

1 is a condenser installed at the bottom of the low-pressure turbine, which is always kept in a vacuum.

The steam flowing into the low-pressure turbine passes through the low-pressure turbine, is cooled by the cooling pipe of the condenser 1, and is stored in a hot well.

A vacuum transmitter 2 is attached to the condenser 1 via a connecting pipe.

This is a device that detects the vacuum value of the condenser 1 and converts it into an electrical signal.

Further, an air pipe having an air opening 5 at one end is connected to the condenser 1, and a vacuum pressure control valve 3 is installed in the middle of the pipe, and this control valve 3 is connected to an electro-pneumatic converter 4. There is.

On the other hand, a lid detector 14 is arranged near the turbine shaft 15,
The electrical signal of the lid detected here is sent to the extensometer 6 and amplified.

This lid meter 6 is connected to a lid recorder 7 and also to a lid signal converter 8, and further communicates with a controller 9 via this converter 8.

This controller 9 is connected not only to the vacuum transmitter 2 and the electropneumatic converter 4 described above, but also preferably to a changeover switch 10, which includes an exclusion side 12 and a use side 13.
It is possible to switch between

In the above configuration, the vacuum transmitter 2 converts the vacuum value of the condenser 1 into an electrical signal and inputs it to the controller 9.

Further, the turbine shaft 15 and the lid of the vehicle compartment are detected by a lid detector 14, and the electrical signal thereof is amplified by a lid detector 6.
The value is recorded in the lid recorder 7 and sent to the lid signal converter 8, where it is converted for the controller and then input to the controller 9.

The controller 9 processes this signal and the signal from the vacuum transmitter 2.

If the push-cover signal exceeds a certain set value, a signal is sent to the electro-pneumatic converter 4 in the direction of opening the vacuum pressure control valve 3.

In response to this, the electro-pneumatic converter 4 operates the vacuum pressure control valve 3 in the opening direction to allow air to flow in from the atmosphere opening port 5, and the condenser 1
Lower the vacuum.

When the vacuum in the condenser 1 decreases in this way, the casing of the low-pressure turbine expands and the casing expands, so the turbine shaft 1
5 and the lid is reduced.

The decrease in the press cover is detected by the press cover detector 14, and the press cover signal is fed back to the controller 9 via the press cover meter 6 and the press cover signal converter 8, and from the controller 9 via the electropneumatic converter 4. A signal in the closing direction is sent to the vacuum pressure control valve 3.

The vacuum transmitter 2 is also used to prevent the vacuum of the condenser 1 from falling too low when the vacuum pressure control valve 3 increases in the opening direction, and the vacuum pressure signal transmitted from it is transmitted to the controller 9. The signal is processed together with the press-cover signal.

Incidentally, since this invention device does not need to be used during normal operation of the turbine, the exclusion side 1 can be switched using the changeover switch 10.
It is preferable to select 2, transmit the fully closed signal 11, select the vacuum pressure control valve 3, and select the use side 13 when necessary to operate the inventive device.

In summary, since the turbine operation control device of the present invention automatically performs the vacuum reduction operation of the condenser,
During turbine load operation, it is possible to quickly prevent a temporary increase in the cover that occurs when the load suddenly decreases or when the plant trips.

[Brief explanation of the drawing]

The drawing shows the components of a turbine operation control device showing an embodiment of the present invention. 1...Condenser, 2...Vacuum transmitter, 3
...Vacuum pressure control valve, 4...Electro-pneumatic converter, 5...Atmospheric release port, 6...Lift gauge, 8... ...Lid signal converter, 9...controller, 10...changeover switch, 14...
Lid detector, 15...Turbine shaft.

Claims (1)

[Claims] 1 The first part communicates with the inside of the condenser and detects the vacuum value of the condenser.
a detection device, a vacuum pressure control valve provided in communication with the condenser, a second detection device provided inside the turbine to detect a lid between the turbine shaft and the casing, and a detection device for detecting the first and second A turbine operation control device comprising: a control device that compares operating commands of a detection device and controls the vacuum pressure control valve.