JPH051660Y2 - - Google Patents

Description

[Detailed description of the invention] A. Industrial application field The present invention relates to a pressure control device that controls the pressure on the inlet side of a water turbine.The invention is related to a pressure control device that controls the pressure on the inlet side of a water turbine. This is to ease the rise.

B. Overview of the invention This invention is a pressure control device that alleviates the pressure increase on the inlet side of a water turbine. A pressure control valve is provided in a branch pipe connected to the inlet side of the water turbine and leading to the discharge side, and this pressure control valve is used as a guide for the water turbine. In addition to performing the opening operation in conjunction with the closing operation of the vane, it is also possible to perform the opening operation independently, so that even if an abnormal increase in pressure occurs on the turbine inlet side for any reason, the pressure control valve is opened and the turbine inlet side is opened. Water was released through branch pipes to help alleviate the pressure rise.

C. Prior Art and Problems Generally, in a water turbine, when the load suddenly decreases due to an accident or the like and power generation is to be stopped, it is necessary to abruptly close the guide vane on the upstream side of the runner. This is because if the guide vanes are closed slowly during loading and unloading, the rotational speed of the runner will increase, which is dangerous. However, when the guide vane is suddenly closed in this way, the water pressure inside the inlet pipe increases rapidly.
New dangers arise.

In the past, as a countermeasure against sudden increases in water pressure, pressure regulators were installed to release the pressure in the inlet pipe. but,
Pressure suppressors operate only in abnormal situations such as when water pressure suddenly rises, so they are prone to rust and malfunction, and are extremely unreliable. In addition, the suppressor is
Because it is installed separately from the water turbine, it requires extra parts, work, and space, such as piping and installation space. Furthermore, with mechanical pressure suppressors, there is a problem that the response is delayed because the work is carried out after the pressure starts to rise.

The present invention has been made in view of the above-mentioned conventional situation, and an object of the present invention is to provide a pressure control device for a water turbine that can reliably alleviate an increase in water pressure.

D. Means for Solving the Problems The configuration of the present invention that achieves the above object is such that a guide vane operating actuator is connected to an operating arm connected to a guide vane of the water turbine, and a guide vane operating actuator is connected to the inlet pipe of the water turbine on the discharge side. A branch pipe that communicates with the guide vane is connected, a pressure control valve that cuts off communication within the branch pipe is provided in the branch pipe, and the operating arm of the pressure control valve and the operation arm for the guide vane are connected by an actuator for the pressure control valve, and the control valve is connected to the guide vane. A pressure control device for a water turbine is provided in which a vane operating actuator and a pressure control valve actuator can each be operated independently.

E Function In this water turbine pressure control device, the operating arm for the guide vane and the control arm for the pressure control valve are connected by an actuator for operating the guide vane, so when the guide vane is closed, the pressure control valve is connected to the closing operation of the guide vane. opens, the water on the turbine inlet pipe side is released through the branch pipe, and the pressure increase on the turbine inlet pipe side due to the guide vane closing is alleviated. If the pressure inside the inlet pipe increases for some reason, the pressure control valve is opened by the actuator for the pressure control valve, and the pressure increase in the inlet pipe is alleviated.

F Embodiment FIG. 1 shows a partially sectional side view of a water turbine equipped with a pressure control device according to an embodiment. Although the pressure control device according to the present invention can be applied to any water turbine, this example shows an application to a horizontal shaft type Francis water turbine.

1 is a water wheel, 2 is its casing, 3 is a speed ring equipped with a guide vane located around the runner in the casing 2, and the speed ring 3 and the guide vane shaft 4 are connected by a link 5. . In other words, the guide vanes are opened and closed by rotating the speed ring 3.
A guide vane operating arm 6 is coupled to the speed ring 3, and the other end of an actuator 7 whose base end is supported by a clevis on a fixed portion around the waterwheel is coupled to this operating arm 6. As the actuator 7, for example, an electric actuator or the like is adopted.

8 is a draft pipe connected to the outlet side of the water turbine 1, 9 is an inlet pipe connected to the inlet side of the water turbine 1, and this inlet pipe 9 has a branch pipe 10 leading to the discharge side.
is connected. 10a is a water discharge pipe connected to the end of the branch pipe 10. The branch pipe 10 is provided with a rotary valve 11 as a pressure control valve that communicates or blocks the inside of the branch pipe 10 . The rotary valve 11 has a valve body 11b having a water passage 11a housed in a valve box 11c, and by rotating the valve body 11b with a valve shaft 11d, the water passage 11a
is connected to or disconnected from the branch pipe 10. 11e
is the valve opening degree detector. An operating arm 12 is attached to the valve shaft integral with the valve body 11b, and an actuator 13 for operating the rotary valve 11 is connected between this operating arm 12 and the operating arm 6 for the guide vane. In this embodiment, the actuator 13 is operated by a variable speed motor, a pole change motor, or two motors with different operating speeds, so that two types of operation, rapid operation and slow operation, can be performed. There is. This actuator 13, like the actuator 7, is connected to the guide vane operating arm 6, so when the actuator 7 operates, the actuator 13 also necessarily moves together.

In the figure, 14 is a pressure sensor provided in the inlet pipe 9 to detect the pressure inside the inlet pipe 9. When the pressure detected by the pressure sensor 14 becomes abnormally high,
The actuator 13 for the rotary valve is adapted to be actuated. 15 is a filter provided in the inlet pipe 9 on the downstream side of the branch pipe 10.

Next, the pressure control operation of the pressure control device will be explained.

When the water turbine 1 is in operation, the actuators 7 and 13 are in an extended state. In other words, the speed ring 3 rotates via the operating arm 6, and the guide vane is in an open state. At this time,
The rotary valve 11 in the branch pipe 10 is in a closed state.

When stopping the water turbine 1 to stop power generation by reducing the load on the water turbine 1, actuators 7 and 1
3 is rapidly actuated in the direction of contraction, the guide vane is closed, the rotary valve 11 is opened via the actuator 13, and water in the inlet pipe 9 is discharged through the branch pipe 10. Since the water in the inlet pipe 9 is discharged, an abnormal increase in pressure in the inlet pipe 9 due to the closing of the guide vane is prevented. The actuator 7 is operated arbitrarily according to the load applied to the water turbine 1 or the dam water level, but when the load is cut off, it is operated rapidly to close the guide vane. The diameter of the water passage 11a of the rotary valve 11 is designed to be large enough to release the above pressure increase.

When the guide vane is completely closed, the actuator 13 is operated at low speed to gradually close the rotary valve 11 via the operating arm 12. The operating speed of the actuator 13 that closes the rotary valve 11 is determined by the water system, and is set so that the pressure inside the inlet pipe 9 does not rise abnormally.

Also, when the pressure sensor 14 detects an abnormal pressure rise in the inlet pipe 9 even when the guide vane is not closed, the actuator 13 is rapidly operated by a control system (not shown) to close the rotary valve 1.
1 is opened, and abnormal pressure rise within the inlet pipe 9 is suppressed. The opening degree of the rotary valve 11 is determined by the rate of increase in pressure detected by the pressure sensor 14, and the opening degree of the rotary valve 11 is detected by a valve opening degree detector 11e to minimize wasteful discharge. It is also possible to control the Furthermore, the guide vane operating arm 6 is designed to prevent inadvertent discharge during normal operation within a range where no pressure rise occurs.
At the same time as the operation of , the actuator 13 is rapidly operated to prevent the rotary valve 11 from opening.
It is also possible to keep unnecessary water discharge to a minimum.
The device can also be simplified by limiting the actuator 13 to a rapid opening direction and a slow closing direction of the rotary valve 11.

In the embodiment described above, since the filter 15 is provided at the connection part of the branch pipe 10, foreign matter adhering to the filter 15 can be discharged by discharging water through the branch pipe 10.

Further, in the above embodiment, a rotary valve is used as the pressure control valve, but the present invention is not limited to this, and other valves such as a butterfly valve can also be used.

G Effect of the invention According to the pressure control device according to the present invention, even if the guide vane of the water turbine is suddenly closed, the pressure control valve opens and the pressure can be released, so the guide vane can be closed safely and quickly. Since the operating speed of the guide vane of the water turbine can be set arbitrarily regardless of the limit on the increase in inlet pipe pressure, the increase in speed of the water turbine when the water turbine is unloaded or disconnected can be reduced. Therefore, there is no need to add a large flywheel to the water turbine generator. Furthermore, since the actuator that operates the pressure control valve can operate independently, it can cope with any rise in pressure and eliminates wasteful discharge of water. Furthermore, since the pressure control device according to the present invention has a simple structure and a small number of parts, maintenance is easy and it is advantageous in terms of installation space.

[Brief explanation of drawings]

FIG. 1 is a partially sectional side view of a water turbine equipped with a pressure control device according to an embodiment of the present invention. In the drawing, 1 is a water turbine, 3 is a speed ring, 6 is an operating arm for the guide vane, 7 is an actuator for operating the guide vane, 9 is an inlet pipe, 10 is a branch pipe, 11 is a rotary valve, and 12 is for a rotary valve. 13 is an actuator for operating a rotary valve, and 14 is a pressure sensor.

Claims (1)

[Claim for Utility Model Registration] A branch pipe 10 leading to the discharge side is connected to the inlet pipe 9 of the water turbine 1, which is formed by connecting an actuator 7 for operating a guide vane to an operating arm 6 connected to a guide vane of the water turbine 1. A pressure control valve 11 is provided in this branch pipe 10 to cut off communication within the branch pipe 10, and an operating arm 12 of this pressure control valve 11 and the operating arm 6 for the guide vane are connected by an actuator 13 for the pressure control valve. A pressure control device for a water turbine, characterized in that the guide vane operating actuator 7 and the pressure control valve actuator 13 can each be operated independently.