JP2669106B2 - Water turbine self-opening pressure distribution valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial applications]

The present invention relates to a pressure distribution valve for distributing a working fluid to a guide vane or needle servomotor in a run-of-river hydroelectric power plant without a spillway.

[Prior art]

In a hydroelectric power plant that does not have a regulating pond, power is generated at the natural flow rate of the river, so excess water is discharged, resulting in a reduction in power generation output when the flow rate is insufficient. Such a power plant is called a run-of-river hydropower plant, and the run-of-river power plant is provided with a head tank for guiding and storing water above the power plant by a headrace. A spillway is installed separately from the water pressure passage. When an accident occurs in such a hydroelectric power plant, conventionally, a guide vane or a needle is closed to stop the water turbine to shut off the water flow, so that the water overflowing from the water tank is discharged from the spillway. Therefore, the pressure distribution valve that distributes the working fluid to the servo motor of the guide vane or the servo motor of the needle has been a self-closing type that closes the guide vane or the needle when the hydraulic pressure of the control oil is lost due to an accident at the power plant. The configuration of the pressure distribution valve will be described below with reference to the drawings. FIG. 2 is a sectional view of a conventional self-opening type pressure distributing valve. In the figure,
A bush 2 is provided inside a casing 1, a cover 3 is provided at the bottom of the bush 2, and a pilot valve 4 is arranged inside the bush 2. An open / close command from the governor is input to the converter 6, and the pilot valve 4 is moved up and down by an output signal of the converter 6. The pilot valve 4 is pulled downward by a spring 5 attached to the lower end of the pilot valve 4. When there is no command to open or close the converter 6 from the governor, the pilot valve 4 is located at the neutral point as a balance between the hydraulic pressure of the control oil at the control oil port D, the weight of the pilot valve 4 and the pulling force of the spring 5. The operation oil boat A is supplied with operation oil from the pressure oil tank,
The open side port B is connected to the open side of the servo motor of the guide vane or needle by the open side pipe 7, and the closed side pipe 8 from the closed side port C is connected to the closed side of the servo motor of the guide vane or needle. . When an open command is issued from the governor, the pilot valve 4 is moved upward by the output signal of the converter 6 so that the operating oil port A and the open side port B communicate with each other to operate the servo motor of the guide vane or the needle to the open side. . When a closing command is issued from the governor, the pilot valve 4 is moved downward by the output signal of the converter 6 so that the operating oil port A and the closing side port C communicate with each other to operate the servo motor of the guide vane or the needle to the closing side. . When the oil pressure of the control oil is lost due to an accident at the power plant, the control oil is no longer supplied to the control oil port D, the pilot valve 4 is lowered by its own weight and the pulling force of the spring 5, and the operation oil port A and the closing side port C are connected. And actuate the guide vane or needle servomotor to the closed side. Therefore,
The conventional pressure distributing valve is a self-closing type that closes a guide vane or a needle that controls the water flow of a water turbine when the control oil loses hydraulic pressure.

[Problems to be solved by the invention]

If the spillway is omitted in a run-of-river hydroelectric power plant, when the control oil loses hydraulic pressure, the pressure distribution valve that distributes the working fluid (generally oil) to the servo motor of the guide vane or needle has traditionally been Since it is a self-closing type, when the guide vanes or needles are closed to cut off the water flow, the water in the water conduit accumulates in the upper water tank and further overflows from the upper water tank. It is an object of the present invention to provide a self-opening type pressure distribution valve that distributes a working fluid so as to open a guide vane or a needle when control oil loses hydraulic pressure due to an accident at a power plant.

[Means for Solving the Problems]

The above objective is to operate the guide vanes or needles of a turbine in a run-of-river hydropower plant with no spillway.
Input the opening and closing commands from the guide vanes to the converter,
The pilot valve is moved up and down by the output signal of the converter to communicate the pressure oil supplied from the operating oil port with the open side port or the close side port, and the guide vane servomotor from the open side port through the open side pipe or Connect to the open side of the needle servo motor to open the guide vane or needle, or connect the closed side port to the closed side of the guide vane servo motor or needle servo motor to connect the guide vane or needle to the guide side. In addition to closing, when there is no open / close command to the converter, control oil is supplied from the control oil port to restore the pilot valve to the neutral position, and when the control oil pressure is lost, the closing side port and the operating oil port In the pressure distribution valve of the turbine that communicates with the
While operating the converter by reversing the closing command, the closing side pipe is connected to the opening side port to operate the guide vane motor or the needle servomotor to the closing side, and the opening side pipe is connected to the closing side port. It is achieved by connecting and operating the guide vane servomotor or needle servomotor to the open side, and when the hydraulic pressure to the control oil port is lost, operating the governor servomotor or the needle servomotor to the open side. .

[Operation]

According to this invention, the command from the governor is input to the converter, the pilot valve is moved up and down by the output signal of the converter, and the operating oil supplied from the operating oil port is communicated with the open side port or the closed side port. When operating oil is connected to the open or closed side of the guide vane servomotor or needle servomotor through the open side pipe or closed side pipe to open or close the guide vane or needle, and there is no open / close command to the converter, In the pressure distributing valve of the hydraulic turbine, in which the control port is supplied with control oil to restore the pilot valve to the neutral position, and when the hydraulic pressure of the control oil is lost, the closing side port and the operating oil port communicate with each other from the governor. When the governor is opened, it becomes a close signal and the pilot is closed. Valve is moved downward, and is an operation fluid port and close side port communicates, closing command of the governor moves upward bi lot valve Te summer and the open command, and the operating oil port and the open-side port communicates. However, the closed side pipe was connected to the open side port and the open side pipe was connected to the closed side port.As a result, when the open command is issued, the servo motor for the guide vane or needle is passed from the closed side port through the open side pipe. When a close command is issued, the guide vane or needle servomotor is closed from the open port through the closed pipe. When the oil pressure of control oil is lost due to an accident at a power plant, the pilot valve is lowered due to the weight of the pilot valve and the tensile force of the spring, and the closing side port and the operating oil port communicate with each other. However, since the open side pipe is connected to the closed side port, the governor or needle servomotor operates to the open side and the turbine continues to discharge.

【Example】

An embodiment of the present invention will be described below with reference to the drawings. First
FIG. 1 is a sectional view of a self-opening type pressure distribution valve according to an embodiment of the present invention. In FIG. 1, the same parts as those in FIG. 2 are designated by the same reference numerals. Casing 1, bush 2, cover 3, pilot valve 4,
The spring 5 and the converter 6 are the same as in FIG. In addition, operating oil port A, open side port B,
The arrangement of the closing port C and the control oil port D is the same as in FIG. The pressure distributing valve according to the present invention is opened by the governor.
The converter 6 is operated by reversing the closing command. Therefore, when the open command is issued from the governor, the output signal of the converter 6 becomes a close signal, the pilot valve 4 is moved downward, the operating oil port A and the close port C are communicated, and when the close command is issued from the governor, the converter is issued. 6 outputs an open signal to move the pilot valve 4 upward, and the operation oil port A
And open side port B are connected. Further, in the pressure distributing valve according to the present invention, the closed side pipe 8 is connected to the open side port B and the open side pipe 7 is connected to the closed side port C, so that the operating oil of the open side port B is the servo of the guide vane or the needle. Operate the motor to the closing side and close port C
Operating oil drives the guide vane or needle servomotor to the open side. As a result, the opening and closing commands from the governor directly act to open and close the guide vane or needle. However, when the control oil to the control oil port D is lost due to the accident at the power plant, the pilot valve 4 is lowered by its own weight and the tensile force of the spring 5, and the operation oil port A and the closing port C communicate with each other. , The governor or needle servomotor is operated in the opening direction through the opening side pipe 7. Therefore, when the oil pressure of the control oil is lost, the guide vane or the needle is kept open, and the water wheel continues discharging. Therefore, there is no risk of water overflowing from the water tank when the control oil pressure is lost.

【The invention's effect】

According to this invention, since the converter is operated by reversing the opening and closing commands from the governor, the opening command from the governor becomes a closing signal to move the pilot valve downward,
The operating oil port and the closing port are communicated with each other, and the closing command from the governor is an open signal to move the pilot valve upward so that the operating oil port and the opening port are communicated with each other. However, since the closed side pipe was connected to the open side port and the open side pipe was connected to the closed side port, the servo motor is operated to open and close the guide vane or the needle as the open / close command from the governor. . However, when the control oil loses hydraulic pressure due to an accident at the power plant, the pilot valve lowers due to its own weight and the pulling force of the spring, and the operating oil port and the closing port communicate with each other. As a result, the servo motor of the guide vane or needle is operated in the opening direction through the open side pipe connected to the close side port to open the guide vane or needle. Therefore, if the pressure distribution valve according to the present invention is used, when the hydraulic pressure of the control oil is lost, the guide vanes or needles of the water turbine continue to be discharged while the water is not overflowing from the water tank. Therefore, there is no problem even if the spillway is omitted. Moreover, the pressure distribution valve according to the present invention does not require any special design, and can be used as it is.

[Brief description of the drawings]

FIG. 1 is a sectional view of a self-opening type pressure distribution valve according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional self-opening type pressure distribution valve. 4: Pilot valve, 5: Spring, 6: Converter, 7: Open side piping, 8: Closed side piping, A: Operating oil port, B: Open side port, C: Closed side port, D: Control oil port.

Claims (1)

(57) [Claims] 1. An open / close command from a guide vane is input to a converter for operating a guide vane or a needle of a water turbine in a flow-in type hydroelectric power plant having no spillway,
The pilot valve is moved up and down according to the output signal of the converter, the operating oil supplied from the operating oil port is communicated with the open side port or the closed side port, and the guide vane servomotor from the open side port through the open side pipe or Connect to the open side of the needle servo motor to open the guide vane or needle, or connect from the closed port to the closed side of the guide vane servo motor or needle servo motor to connect the guide vane or needle to the closed side. In addition to closing, when there is no open / close command to the converter, control oil is supplied from the control oil port to restore the pilot valve to the neutral position, and when the control oil pressure is lost, the closing side port and the operating oil port When the governor is open,
While operating the converter by reversing the closing command, the closing side pipe is connected to the opening side port to operate the guide vane motor or the needle servomotor to the closing side, and the opening side pipe is connected to the closing side port. A self-opening of a water turbine, characterized in that the guide vane servomotor or the needle servomotor is operated to the open side by connecting and the governor servomotor or the needle servomotor is operated to the open side when the hydraulic pressure of the control oil is lost. Type pressure distribution valve.