JPH0419364A - Adjusted-phase operation controller for hydraulic power machine - Google Patents

Abstract

PURPOSE:To enable reduction in capacity of the pressure oil tank to achieve reduction in building cost of a hydraulic power station by making a control to close the inlet valve in response not only to generation of a closure signal but also to generation of a restoration signal, i.e., restoration of the hydraulic pressure in a pressure oil tank. CONSTITUTION:In a hydraulic power machine, an inlet valve 9 is opened/closed by a servomotor 10, the sarvomotor 10 being driven by a pressurized oil from a pressure oil tank 13 via a pressure distribution valve 12. The system comprises a pressure relay 15 which generates a pump starting signal at the time when the hydraulic pressure in the pressure oil tank 13 falls below the lowest pressure level usually used, and a pressure relay 16 which generates a restoration signal when it has been detected that the oil pressure in a pressure oil tank T exceeds a normal inlet-valve operation permission value P1 capable of normally driving the inlet valve 9 by the servo-motor 10. When a control unit 17 has received both a closure signal from a guide-vane closure detection switch 7 and a restoration signal from the pressure relay 16, a control is so made as to close the pressure distribution valve 12 and thus close the inlet valve 9.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a phase-mixing operation control device used in a hydraulic machine such as a water turbine that performs a phase-mixing operation.

[Conventional technology] Some hydraulic machines such as water turbines used in hydroelectric power plants include
There are some that perform phase adjustment operation. The purpose of this phase adjustment operation is to rotate the water turbine in the air using power from the grid and adjust the reactive power of the power grid. FIG. 4 shows a control sequence during a phase-mixing operation of a hydraulic machine that performs such a phase-mixing operation. When a command to start the phase-mixing operation is issued, the inlet valve is opened (step 100); After detecting that the inlet valve is fully open (step 101), the guide vane is opened (step 102) and the runner is rotated (step 103). When the rotational speed of the water turbine reaches the rated rotation speed controlled by the governor and matches the frequency of the grid, the generator is connected to the grid (step 104).

Since the inlet valve is driven to open by supplying oil from the hydraulic tank to the servo motor, the oil pressure in the pressure oil tank decreases in response to the opening operation of the inlet valve (step 105). A drop in the oil pressure in the pressure oil tank is detected, and in response to this detection, the pressure oil pump is operated to replenish oil to the pressure oil tank (
Step 106).

After the generator is installed, the guide vanes are closed to cut off the water flow (step 107). After the guide vane is fully closed (step 108), compressed air is introduced into the runner chamber to push down the water surface in the runner chamber and drain the water (step 109),
The water wheel is idled for phase adjustment operation. Further, after the guide vane is fully closed, the servo motor is supplied with oil from the hydraulic tank and the inlet valve is closed (step 110).

The pressure oil tank that supplies pressure oil to the servo motor that drives the opening and closing of the inlet valve is designed to provide control pressure to prevent the pressure oil system from becoming too large and to improve reliability as the capacity of hydraulic machinery increases. In many cases, it is installed separately from the pressure oil tank of the oil equipment.

[Problem to be solved by the invention] However, in a hydraulic machine that performs phase-mixing operation, at the start of phase-mixing operation, the pressure oil tank is operated by a servo motor twice to open and close the inlet valve. Oil must be supplied. For this reason, a large-capacity pressure oil tank is required, which poses the problem of significantly increasing the construction cost of the hydroelectric power plant and the maintenance and management cost of the pressure oil equipment for the inlet valve.

SUMMARY OF THE INVENTION Therefore, the purpose of the present invention is to reduce the capacity of a pressure oil tank for an inlet valve by using a phase adjusting and shifting control system for hydraulic machinery.
Our goal is to provide the following.

[Means for Solving the Problems] In order to achieve this object, the present invention includes an inlet valve, a pressure oil tank, and a servo motor that drives the inlet valve to open and close using the pressure oil supplied from the pressure oil tank. and a pressure oil pump that supplies pressure oil to the pressure oil tank, and after starting the hydraulic machine and connecting the generator to the system by opening the inlet valve and opening the guide vane, the guide vane In the phase adjustment operation control device for a hydraulic machine that performs phase adjustment operation by closing the inlet valve and closing the inlet valve, detecting that the pressure in the pressure oil tank becomes equal to or lower than a first predetermined value, Pressure detection means for starting the pressure oil pump, detecting that the pressure in the pressure oil tank has recovered to a second predetermined value due to the activation of the pressure oil pump, and generating a recovery signal, and closing the guide vane. a guide vane closure detection means for detecting the closure signal and generating a closure signal; and a guide vane closure detection means for supplying the pressure oil from the pressure oil tank to the servo motor when both the recovery signal and the closure signal are generated. The invention is characterized by comprising a control means for closing the inlet valve.

[Function] The pressure oil tank supplies pressure oil to the servo motor for opening the inlet valve. When the pressure in the pressure oil tank decreases to a first predetermined value or less due to this oil supply, the pressure detection means detects this and starts the pressure oil pump to replenish the oil in the pressure oil tank.

After opening the guide vanes, rotating the water turbine, and installing the generator,
The guide vanes are closed. When the guide vane closure detection means detects the guide vane closure, it generates a closure signal. When the pressure in the pressure oil tank recovers to a second predetermined value due to oil replenishment by the pressure oil pump, the pressure detection means detects this and generates a recovery signal.

The control means is arranged such that when both the closing signal and the recovery signal are generated,
Supply pressure oil from the pressure oil tank to the servo motor and close the inlet valve.

The inlet valve is closed not only after the guide vane closing signal is generated, but also after the pressure recovery signal for the pressure oil tank is generated, that is, the oil pressure in the pressure oil tank is restored, which increases the capacity of the pressure oil tank. becomes unnecessary.

[Embodiment] Hereinafter, an embodiment of a phase adjustment operation control device for a hydraulic machine according to the present invention will be described with reference to FIGS. 1 to 3.

In FIG. 1, a runner 2 in a runner room 1 is connected to a generator 4 by a main shaft 3, and this generator 4 is connected to a power grid 6 by a circuit breaker 5. The guide vane closing detection switch 7 detects that the guide vane 8 is closed and generates a closing signal. Inlet valve 9 is driven by servo motor 1
The fully open state of the inlet valve 9 is detected by the inlet valve detection switch 11. Servo motor 1
0 is driven by pressure oil from a pressure oil tank 13 via a pressure distribution valve 12. The pressure oil pump 14 supplies oil in the oil collection tank T to the pressure oil tank 13.

The pressure of the pressure oil in the pressure oil tank T is detected by pressure relays 15 and 16. This pressure relay 15 is connected to the pressure oil tank 1
A pump start signal is generated when the oil pressure of No. 3 becomes less than the minimum working oil pressure, and a pump stop signal is generated when the oil pressure becomes more than the maximum working oil pressure.

These pump start signals and pump stop signals are input to a pressure oil pump control device (not shown) to start and stop the pressure oil pump 14, respectively, and control intermittent operation. The pressure relay 16 detects that the oil pressure in the pressure oil tank T is equal to or higher than a predetermined value P1, specifically, an inlet valve normal operation oil pressure value P1 that allows the servo motor 10 to normally drive the inlet valve 9. At the same time, a recovery signal is generated and sent to the control device 17.

This control device 17 includes a guide vane closure detection switch 7
and the output of the pressure relay 16, and the closing signal from the guide vane closing detection switch 7 and the pressure relay 1
When the recovery signal from 6 is input together, the pressure regulating valve 12 is closed. The closing operation of the pressure distribution valve 12 sends pressure oil from the pressure oil tank 13 to the servo motor 10 and causes the inlet valve 9 to close. The air tank 18 injects compressed air into the lunch room 1 via the air supply valve 19.

Next, the operation of this embodiment will be explained using FIGS. 1 to 3.

When the start of the phase adjustment operation is commanded, the pressure distribution valve 13 is opened, pressure oil from the pressure oil tank 13 is supplied to the servo motor 10, and the inlet valve 9 is opened (step 20 in FIG. 2). As pressure oil is supplied from the pressure oil tank 13 to the servo motor 10, as shown in FIG. detects this, generates a pump start signal, starts the pressure oil pump 14, and transfers the oil in the oil collection tank T to the pressure oil tank 1.
3 (step 22).

When the first port valve 9 is fully opened, the inlet valve detection switch 11 detects this (Step 23), and in response to this detection, the guide vane 8 is opened to the starting opening by the load limiting device of the speed governor (not shown). (Step 24). As a result, pressurized water flows from the upper pond U into the runner 2, rotates the runner 2 (step 25), and flows out into the lower pond V. When the rotation of the runner 2 increases and reaches a predetermined speed, the guide vane 8 is closed to the no-load opening, and the speed governor starts controlling the speed to control the rotation speed of the guide vane 8 to the rated speed. When the frequency matches the frequency of the system 6, the generator 4 is connected to the system 6 by the circuit breaker 5 (step 26).

Immediately after this parallel entry, the guide vane 8 is closed (step 27), and when the guide vane closure detection switch 7 detects that the guide vane 8 is fully open (step 28), a closing signal is sent to the control device 17.

When the water flow is cut off by fully opening the guide vane 8, the air supply valve 19 supplies compressed air from the air tank 18 to the lunch room.
Step 29)
, the runner 2 is idled to start phase adjustment operation.

The oil pressure in the pressure oil tank 13 is changed to the pressure oil pump 1 in step 22.
When the pressure gradually increases through the operation of step 4 and reaches the inlet valve normal operation hydraulic pressure value P1, the pressure relay 16 detects this and sends a recovery signal to the control device 17 (step 30). Since the control device 17 has already input the closing signal from the guide vane closing detection switch 7, it closes the pressure distribution valve 12 in response to the input of the recovery signal. As a result, the servo motor 10 closes the inlet valve 9 using the oil pressure of the pressure oil tank 13 (step 31).

After that, when the pressure oil tank 13 reaches the maximum normal oil pressure, the pressure relay 15 detects this and generates a pump stop signal.
The operation of the pressure oil pump 14 is stopped.

As described above, the pressure oil tank 13 supplies oil to the servo motor 10 in order to open the inlet valve 9, and after the oil pressure decreases, a recovery signal is generated even if a guide vane close signal is generated. The servo motor 10 is not refueled until the oil pressure is sufficiently recovered. Therefore, the pressure oil tank 13 can be significantly downsized compared to conventional hydraulic machines, and even if this small capacity pressure oil tank 13 is used, the time from the opening of the inlet valve to the start of phase adjustment operation is can be done as quickly as with conventional hydraulic machines.

Note that in the above embodiment, the guide vane 8 was fully closed in step 27. However, in step 27, the guide vane 8 may be slightly opened instead of being fully closed. Therefore, in this specification, closing the guide vane includes both fully opening and slightly opening the guide vane.

[Effects of the Invention] As is clear from the above description, according to the present invention, when the pressure in the pressure oil tank is detected to be equal to or lower than the first predetermined value, the pressure oil pump is activated, and this pressure is activated. pressure detection means for detecting that the pressure in the pressure oil tank has recovered to a second predetermined value due to activation of the oil pump and generating a recovery signal;
A guide vane closing detection means detects the closing of the guide vane and generates a closing signal, and when both a recovery signal and the above-mentioned closing signal are generated, supplying pressure oil from a pressure oil tank to a servo motor and inlet. Since the inlet valve is equipped with a control means for closing the valve, the inlet valve is closed not only after the closing signal is generated, but also after the generation of the recovery signal, that is, the recovery of the oil pressure in the pressure oil tank. This makes it possible to reduce the capacity of the tank, significantly reducing construction costs for hydroelectric power plants and maintenance and management costs for pressure oil equipment for inlet valves.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing one embodiment of the phase adjustment control device for hydraulic machinery according to the present invention, Fig. 2 is a sequence diagram showing the control sequence of the above embodiment, and Fig. 3 is a system diagram showing each of the above embodiments. A timing chart diagram showing the operation of the members, and FIG. 4 are explanatory diagrams showing a control sequence of a conventional phase adjustment operation control device for a hydraulic machine. 4... Generator, 6... System, 7... Guide vane closure detection switch, 8... Guide vane, 9... Inlet valve, 10... Servo motor, 13... Pressure oil tank,
14... Pressure oil pump, 15.16... Pressure detection means, 17... Control means

Claims (1)

[Claims] 1. Equipped with an inlet valve, a pressure oil tank, a servo motor that opens and closes the inlet valve using pressure oil supplied from the pressure oil tank, and a pressure oil pump that supplies pressure oil to the pressure oil tank. , after starting the hydraulic machine and connecting the generator to the system by opening the inlet valve and opening the guide vane,
In a phasing operation control device for a hydraulic machine that performs phasing operation by closing the guide vane and closing the inlet valve, it is detected that the pressure in the pressure oil tank has become equal to or less than a first predetermined value. pressure detection means for detecting that the pressure in the pressure oil tank has recovered to a second predetermined value due to the activation of the pressure oil pump and generating a recovery signal; and the guide. a guide vane closure detection means that detects closure of the vane and generates a closure signal, and supplies the servo motor with the pressure oil from the pressure oil tank when both the recovery signal and the closure signal are generated. and control means for closing the inlet valve.