JPH07317642A - Phase modification operation method for pumped storage power generator - Google Patents

Abstract

PURPOSE:To reduce the air quantity required for pushing the water surface down and simplify the determination of the opening/closing control time of the first automatic valve and the second automatic valve by utilizing the priming hydraulic characteristic diagram and draft hydraulic characteristic diagram, and preventing the fountain in a lower pond with the compressed air at the time of phase modification. CONSTITUTION:Air is fed from the first air feed pipe 16A and the =second air feed pipe 19A to a runner chamber 15 and a suction pipe 13 at Tl when the closing of a guide vane 3 is completed after the opening/closing is started or at T1 when the priming hydraulic pressure in a runner chamber is the maximum. The second air feed pipe 19A is closed at T2 when the water surface is separated from the runner 2 and the effect of the pressure fluctuation by the rotation of the runner 2 is reduced after the water level in the runner chamber starts to be lowered and the pressure fluctuation of the hydraulic pressure is started by the rotation of the runner 2. The first air feed pipe 16A is closed at T3 located nearly at the center between T1 when the priming hydraulic pressure is the maximum and the time at the minimum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Francis type pump turbine, and more particularly to an operating state in which a runner is rotated in the air from a pumping operation state or a power generating operation state without stopping the pump turbine, that is, a standby operation or a phase adjustment. The present invention relates to a method for controlling a pumped storage power generation device that switches operation to operation.

[0002]

2. Description of the Related Art According to the method of operating a water turbine or a pump water turbine described in JP-B-60-42357, page 3, column 5, line 29 to column 6, line 12, the turbine or pump is operated. In a hydraulic machine such as a water turbine directly connected to a synchronous generator, when the power factor of a power system decreases, a phase-shift operation is performed to improve it.

With the phasing operation command, the inlet valve is opened,
The pressure in the casing is increased, subsequently the guide vanes are opened and the high pressure water in the casing causes the runner to rotate. When the runner and the rotary electric machine directly connected to the runner, such as a generator, reach the rated speed, they are put in parallel with the power system. When they are inserted in parallel, the guide vane opening is fully closed, the air supply valve is opened, and compressed air is sent into the runner chamber to push down the water surface in the runner chamber and start closing the inlet valve to rotate the runner in the air. So-called phase-matching operation is performed.

There is a phenomenon in which the priming water pressure on the outer peripheral portion of the runner does not sufficiently decrease in the phase-adjustment operation. This phenomenon pushes down the water surface while rotating the runner, so that the centrifugal action of the runner causes water to remain on the outer peripheral side of the runner. This is because the replacement of water in the runner with air is delayed because only the center of the runner is filled with air.

As a method for smoothly replacing the water remaining on the outer periphery of the runner with air when pushing down the water surface, for example, in Japanese Examined Patent Publication No. 60-42357, the water level is pushed down below the runner and the air supply valve is turned on. After closing the inlet valve and then closing the inlet valve completely, the leaker drainage valve is opened after the outer peripheral pressure of the runner drops to near the draft water pressure.In Japanese Patent Publication No. 46-39172, the air level in the runner chamber is reduced by injecting compressed air. Is pushed down from the lower end of the runner, and the water in the outer periphery of the runner is opened to the lower cover near the outer periphery of the runner and discharged to the suction pipe by the discharge pipe communicating with the suction pipe, and the runner is idled. .

On the other hand, the swirling flow in the suction pipe, which is induced by the runner, has become more intense due to the deeper suction height of the equipment and the higher peripheral speed of the runner outlet, which are accompanied by the high head and large capacity of the pump turbine. The intensification of the swirling flow in this suction pipe is
For example, the Japan Society of Mechanical Engineers Proceedings No. 740-6 “Model test on empty transition from pump-turbine pumping operation” has the effect of strengthening the downward flow in the suction pipe as shown on page 81, and determines the amount of bubbles flowing to the lower pond side. Increase. Therefore, in a high-head and large-capacity pump turbine, a large amount of air is required to push down the water surface, and it is necessary to increase the diameter or number of air supply pipes. However, if the air supply flow rate from the upper cover side is increased, the water filling the runner back pressure chamber will be removed in a short time at the start of air supply, and the pressure in the back pressure chamber will be temporarily reduced immediately after the start of air supply. There was a risk that the runner would momentarily generate an excessive downward thrust.

Therefore, when the air supply pipes are provided on both the upper cover and the upper suction pipe in the upper part of the runner chamber, and when the water surface is pushed down while rotating the runner, a method of supplying compressed air from both has been adopted.

[0008]

On the other hand, when pushing down the water surface while rotating the runner, the air flow rate reaches several tens of cubic meters per second in terms of atmospheric pressure, and from 30% to 5
It is considered that 0% is leaked to the Shimoike side. In addition, the above-mentioned Proceedings of the Japan Society of Mechanical Engineers, No. 740-6, "Model Experiments on Empty Transition from Pumped Pumping Operation" 8
According to the description of FIG. 7 on pages 3 to 84, the amount of air required to push down the water surface is smaller when air is supplied from the upper cover via the boss than when air is supplied from the suction pipe. If you notice, it is said to be an intermediate amount.

Therefore, the air supplied from the upper suction pipe side has a larger rate of air leakage to the lower pond side in general than the air supplied from the upper cover side. At the time when the water surface is below the lower end of the runner, the flow of water from the runner to the suction pipe is prevented from flowing, and the rate of air leakage from the upper cover is reduced. As for the air supply from the upper suction pipe side, even if the water surface is below the lower end of the runner, the air leakage rate does not change because it is supplied into the water.

Therefore, when switching to the phase-shifting operation of pushing down the water surface while rotating the runner, when air is supplied only from the upper suction pipe side or air is supplied from the upper suction pipe side to the water level depression completion water level. May pass through the discharge channel with an increase in the capacity of the pump turbine, and the amount of air leaked to the lower pond side may be excessive, causing a large amount of water to gush out from the discharge channel gate and other openings. was there.

The object of the present invention is to prevent compressed air from leaking to the lower pond side during phase adjustment, to reduce the amount of air required to push down the water surface, and to control the first automatic valve 16 and the second automatic valve 19.
An object of the present invention is to provide a phased operation method for a pumped storage power generation device, which can easily determine the opening / closing control time of

[0012]

SUMMARY OF THE INVENTION A phase-shifting operation method for a pumped-storage power plant according to the present invention comprises closing a guide vane in a runner chamber,
Air is injected from the first supply pipe and the second supply pipe provided in the runner chamber and the suction pipe on the downstream side of the runner chamber to lower the water level of the runner and start closing the guide vanes in the phase-adjusting operation of rotating the runner. From the time of completion of closing T1 or when the priming water pressure in the runner chamber is maximum T1, air is supplied to the runner chamber and the suction pipe from the first supply pipe and the second supply pipe,
After lowering the water level in the runner chamber, the pressure fluctuation of the water pressure starts due to the rotation of the runner, the water surface is separated from the runner, and the influence of the pressure fluctuation becomes small due to the rotation of the runner, after closing the second supply pipe at T2, Maximum priming pressure T1
The first supply pipe is closed at a time T3 approximately midway between the time and the minimum time.

[0013]

As described above, according to the present invention, the time T2 and the time T
Since the first supply pipe is closed after the second supply pipe is closed at 2 o'clock, opening / closing control of the first supply pipe and the second supply pipe is facilitated, and compressed air is prevented from leaking to the lower pond side. This has made it possible to reduce the amount of air required to push down the water surface.

[0014]

Embodiments of the present invention will be described below with reference to FIGS. The entire pump turbine has the configuration shown in FIG. 3, the Francis type pump turbine has the configuration shown in the schematic side sectional view of FIG. 1, and the entire pump turbine has the configuration shown in FIG.

A rotating electric machine (not shown) such as a generator motor is mounted on the upper side of the main shaft 1, and a centrifugal runner 2 is connected to the lower flange of the main shaft with bolts to rotate about the shaft. The main shaft 1 has a lower flange provided with a through hole 1A through which air passes during air supply / exhaust to push down the water surface. Circular blade rows are arranged on the high pressure side of the runner 2 and guide vanes 3 are provided around the spindle.
Is rotatably attached.

The guide vane 3 is rotatably supported by the upper cover 4 and the lower cover 5, and the upper cover 4 and the lower cover 5 are supported.
Are upper and lower speed rings 7 that are parallel to each other and are arranged on the outer peripheral side of the guide vane 3 in a circular blade row, and the stay vane 6 includes two flanges.
A and 7B are welded and joined. The casing 8 is arranged in a spiral shape outside the stay vane 6, and both ends of the cross section are welded to the upper and lower speed rings 7A and 7B.

An iron pipe 9 is provided on the spirally upstream side of the casing 8, and an inlet valve 10 connects the iron pipe 9 and the casing 8.
In order to equalize the internal pressure of the iron pipe 9 and the internal pressure of the casing 8 when the inlet valve 10 is fully closed, the pipe 11 is connected to the iron pipe 9 and the casing 8.
A is connected, and the side valve 11 is connected to the pipe 11A.

The upper suction pipe 13 has a conical shape that spreads downward to the lower side of the runner 2. A water level detector 12 for monitoring the water level after completion of the water surface depression and the water surface depression is attached to the upper suction pipe 13 and The outlet of the lower suction pipe 14 connected to the lower side of the suction pipe 13 is bent in the horizontal direction.

Guide vanes 3, upper cover 4 and lower cover 5
The runner chamber 15 surrounded by the upper suction pipe 13 and the upper suction pipe 13 is provided with the first air supply pipe 16A on the upper cover 4. The first air supply pipe 16A is a main shaft back pressure chamber 17 surrounded by the lower flange of the main shaft 1 and the upper cover 4, and a through hole 1A provided in the main shaft 1.
Air is supplied to the lower portion of the runner 2 through the runner chamber 15
The water surface inside is pushed down to the position of the water level detector 12.

The first automatic valve 16 is provided and the first air supply pipe 1
Control 6A air. The second air supply pipe 19A having the second automatic valve 19 is connected to the upper suction pipe 13 and
Like the first air supply pipe 16A, it functions to supply air into the runner chamber 15.

As a means for detecting that the water surface inside the runner chamber 15 is below the lower end surface of the runner 2 while the water surface is being pushed down, the water level gauge provided directly below the runner 2 of the upper suction pipe 13 is installed in the runner chamber 15. Alternatively, the pressure detector 20A or the pressure detector 20B provided on the upper cover 4 or the lower cover 5 of the outer peripheral portion of the runner chamber 15 is provided, and is calculated from the detection signal of the water level gauge or the pressure detector 20A or the pressure detector 20B. The control device 23 detects that the water surface in the runner chamber 15 has become lower than or equal to the lower end surface of the runner 2, and the second air supply pipe 19A
2 outputs the closing operation signal of the operation solenoid valve 24 of the second automatic valve 19 provided in FIG.

The solenoid valve 24 for operation of the second automatic valve 19 receives a closing operation signal, and a hydraulic oil pipe 2 is supplied from a pressure oil source (not shown).
The pressure oil supplied through No. 5 is supplied to the hydraulic pipe 26 on the closing operation side of the second automatic valve 19 to stop the supply of air from the first air supply pipe 19A to the runner chamber 15.

The drainage pipe 21A provided between the side pressure chamber 18 surrounded by the runner 2 and the lower cover 5 and the upper suction pipe 13 or the lower suction pipe 14 sucks water in the side pressure chamber by the third automatic valve 21. Discharge to tube 13 or 14. Further, the drainage pipe 22A provided between the middle portion between the outer periphery of the runner 2 and the guide vane 3 and the upper suction pipe 13 or the lower suction pipe 14 sucks the water in the runner 2 and the guide vane 3 by the fourth automatic valve 22. Discharge to tube 13 or 14.

In the pumping operation, the inlet valve 10 and the guide vane 3 are opened while the runner 2 is operated by the generator motor via the main shaft 1, and the water is drawn from the lower pond into the lower suction pipe 13 and the upper suction pipe. It flows into the runner 2 through 14. The water flowing into the runner 2 is pressurized by centrifugal force due to the rotation of the runner 2, passes through the flow passages between the guide vanes 3 and the stay vanes 6, and flows into the casing 8. The water flowing into the casing 8 is pumped to the upper pond via the inlet valve 10 and the iron pipe 9.

In the case of power generation operation, the above-mentioned flow direction is reversed, and the power of water is converted into rotational energy by the runner 2 and transmitted to the generator motor via the main shaft 1.

On the other hand, in the hydraulic machine directly connected to the synchronous generator, when the power factor of the electric power system is lowered, the water surface of the runner chamber 15 is pushed down to improve the power factor, so that the runner 2 is rotated in the air. Phase operation is performed.

Next, the case where the pumping operation or the power generation operation is switched to the phase-shifting operation without stopping the pump turbine will be described with reference to FIGS. 1 to 4.

With the pump turbine operating, the guide vanes 3
After fully closing, the inlet valve 10 is started to be closed, the automatic valve 22 is opened to drain the outer peripheral portion of the runner 2 to the upper suction pipe 13, and the first automatic valve 16 and the second automatic valve 19 are opened. From the first and second air supply pipes 16A and 19A to the runner chamber 1
Compressed air is supplied to the inside of 5 to push down the water surface.

The fact that the water level in the runner chamber 15 has dropped and the water level has become below the runner lower end indicates that the water level gauge or pressure detector 20A provided in the upper suction pipe 13 or the pressure provided in the upper cover 4 or the lower cover 5 From the detection signal of the detector 20B, the arithmetic and control unit 23 detects that the water surface in the runner chamber 15 is below the lower end surface of the runner 2, and detects the second automatic valve 19 provided in the second air supply pipe 19A. Solenoid valve 24 for operation
To output a closing operation signal to close the second automatic valve 19,
The air supply from the air supply pipe 19A to the runner chamber 15 is stopped. The closing time T2 of the second automatic valve 19 will be described later.

The water level in the runner chamber 15 is further lowered by the air supply from the first air supply pipe 16A, and the first automatic valve 1 is activated by the water level detection signal by the water level detector 12 to indicate that the water level has been pushed down.
After closing 6, the third automatic valve 21 provided on the lower cover 5 is opened in order to discharge the water in the side pressure chamber 18 to the upper suction pipe 13 or the lower suction pipe 14, and thereby the phase-adjustment operation is started. The migration is complete. The side valve 11 is closed after the inlet valve is fully closed.

After that, the first automatic valve 16 is turned on by the water level detection signal (not shown) of the water level detector 12, which indicates the rise of the water level due to the air in the runner chamber 15 leaking out of the pump turbine. By opening and replenishing air in the runner chamber 15 to push down the water level, the water level detector 12 closes the first automatic valve 16 again by the water level detection signal indicating that the water level has been pushed down, thereby stabilizing the phased operation state. Continue.

Next, the relationship between the change of the water surface in the runner chamber 15 and the pressure change in the runner chamber 15 and the control of the first automatic valve 16 and the second automatic valve 19 when the water surface is pushed down according to the embodiment of the present invention. Will be described with reference to FIGS. 1 and 4.

The guide vane 3 starts to be closed at time T0 and is completely closed at time T1. During this time, as for the priming water pressure characteristic in the runner chamber, the water pressure is detected by the pressure detector 20B. The pressure starts to rise from the zero pressure start at T0 at the start of closing of power generation or pumping operation, reaches the maximum pressure value at the time T1 of complete closing, and then the priming water pressure decreases and reaches the minimum value at time T4.

The draft water pressure in the upper suction pipe 13 is detected by the pressure detector 20A. The draft water pressure characteristic is that the fluctuation of the water pressure is generated from approximately the middle of the time T0 and the time T1 when the guide vane 3 starts to close and the opening degree becomes small due to the stronger stirring action of the water in the upper suction pipe 13 due to the rotation of the runner 2. After the components gradually increase and the stirring effect of the runner 2 weakens, the components decrease at time T2 and become almost constant.

In these characteristic diagrams, the guide vanes 3
After the valve is fully closed (time T1), a signal is input to the arithmetic and control unit by a guide vane switch (not shown), and the arithmetic and control unit gives an open signal to the first automatic valve 16 and the second automatic valve 19. When the air is started to be supplied into the runner chamber 15 from the second air supply pipes 16A and 19A, the air is first accumulated in the lower portion of the runner 2 near the center of rotation, and thereafter, the air reservoir is gradually increased as the air is supplied. Therefore, the pressure increasing effect of the outer peripheral portion of the runner 2 due to the centrifugal force of the swirling flow of the water in the air pool is reduced, and the priming water pressure of the pressure detector 20B causes the growth of the air pool from time T1 to time T4. Along with this, it gradually decreases.

On the other hand, when the water level in the runner chamber 15 is equivalent to the lower end of the runner 2, the outer peripheral portion of this air reservoir comes into contact with the inner peripheral surface of the band 2B of the runner 2, and the water inside the runner 2 at the inner peripheral portion of the upper suction pipe 13 is contacted. The water film connecting water in the upper suction pipe 13 disappears, and the water supply from the inside of the upper suction pipe 13 into the runner 2 through this water film and the stirring action of the water in the upper suction pipe 13 by the runner 2 are eliminated. It disappears at time T2.

At time T2, the second automatic valve 19 is closed. When the time T3, which is approximately halfway between the time T1 and the time T4, is reached, the first automatic valve 16 is closed. Incidentally, time T0 to time T
Reference numeral 4 is input in advance to the arithmetic and control unit.

As described above, since the second automatic valve 19 is closed at time T2 and the first automatic valve 16 is closed at time T3, the compressed air at the time of phase adjustment can be prevented from being discharged by the fountain in the lower pond. , The amount of air required to push down the water surface has been reduced. Further, since the opening / closing control time of the first automatic valve 16 and the second automatic valve 19 can be determined by using the priming hydraulic pressure characteristic diagram and the draft hydraulic pressure characteristic diagram, the control time can be calculated without complicated calculation. It's easy to decide.

Further, another embodiment will be described with reference to FIG.

In FIG. 4, the first and second automatic valves 16,
19 After opening operation, compressed air is supplied into the runner chamber 15 to push down the water surface, and the time required for the water level in the runner chamber 15 to drop and the water surface to be below the runner lower end is the same pump water turbine. Since there is no significant change in the conditions, it can be calculated from the internal volume of the runner chamber 15 and the air supply amount, or more reliably, can be determined by a field test.

The input signals of the arithmetic and control unit 23 shown in FIG. 2 are inputted to the arithmetic and control unit 23 as signals of the first automatic valve 16 opening command and the second automatic valve 19 opening command, and the arithmetic and control unit 23 is inputted.
When the delay timer provided in is received an opening command from the first automatic valve 16 and an opening command from the second automatic valve 19, the delay timer is set by the priming hydraulic pressure characteristic diagram and the draft hydraulic pressure characteristic diagram calculated in advance or obtained by the field test. The required time from the opening operation of the first automatic valve 16 and the second automatic valve 19 to the water surface being below the runner lower end is set, and the electromagnetic valve 24 is used to close the second automatic valve 19 and the first automatic valve 16, for example. To do. The subsequent steps are the same as in the above embodiment.

[0042]

According to the present invention, in switching from pumping or power generation operation to phase-shifting operation, the second automatic valve 19 is closed at time T2 from the closing of the guide vanes to the completion of the pressing of the water surface, and at time T3, the first automatic valve 19 is closed. Since the 1 automatic valve 16 is closed, it is possible to prevent the compressed air at the time of phase adjustment from being discharged by the fountain in the lower pond and to reduce the amount of air required for pushing down the water surface. Further, since the opening / closing control time of the first automatic valve 16 and the second automatic valve 19 can be determined using the priming hydraulic pressure characteristic diagram and the draft hydraulic pressure characteristic diagram,
It became possible to easily determine the control time without making complicated calculations.

[Brief description of drawings]

FIG. 1 is a detailed sectional view around a runner chamber of a pump turbine according to an embodiment of the present invention used in FIG.

FIG. 2 is a control system diagram of an automatic valve of the method for controlling the phase-shifting operation of FIG.

FIG. 3 is a schematic view showing an entire pump turbine according to an embodiment of the present invention.

FIG. 4 is an operation characteristic diagram of a phase-shifting operation control method for switching from pumping or power generation operation of the pump turbine used in FIGS. 1 and 2 to phase-shifting operation.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Main shaft, 2 ... Runner, 3 ... Guide vane, 12 ... Water level detector, 13 ... Upper suction pipe, 15 ... Runner chamber, 16 and 19 ... 1st and 2nd automatic valve, 16A and 19A ... 1st and 1st 2 air supply pipe, 20 ... water level gauge or pressure detector, 23
... arithmetic control device, 25, 26, 27 ... hydraulic piping.

Claims (5)

[Claims] 1. A guide vane in the runner chamber is closed, and air is injected from a first supply pipe and a second supply pipe provided in the runner chamber and a suction pipe on the downstream side of the runner chamber to supply the first supply pipe and the second supply pipe. Open and close the first automatic valve and the second automatic valve provided in the supply pipe,
In the phasing operation of controlling the air supply, lowering the water level of the runner, and rotating the runner, the guide vane is closed from the start to the completion T1 or when the priming water pressure in the runner chamber is maximum T1. Air is supplied from the second supply pipe to the runner chamber and the suction pipe, the water level in the runner chamber begins to drop, the pressure fluctuation of the water pressure starts due to the rotation of the runner, the water surface separates from the runner, and the influence of the pressure fluctuation due to the rotation of the runner. When the priming water pressure is close to the maximum T1 and the minimum when the priming water pressure is T3, the first automatic valve is closed at the time T3 when the priming water pressure is maximum. Method. 2. The method of operating a phased operation of a pumped storage power generator according to claim 1, wherein the opening and closing of the first and second automatic valves are controlled in accordance with the times T1 to T4 input to the arithmetic control unit. 3. A water level detecting device for detecting that the water level in the runner chamber is lower than the lower end of the runner, and a pressure detecting device is provided under the lower end of the runner of the upper suction pipe. Input the detected value that the pressure fluctuation component disappeared or decreased, and the detected value that the water level in the runner chamber was below the lower end of the runner to the arithmetic control unit, and from the arithmetic control unit monitoring, 1. Pumped storage power generation according to claim 1, wherein the automatic valve of the air supply pipe is fully closed, the second automatic valve provided in the upper suction pipe is maintained open, and further the water level is pushed down to perform air operation. How to operate the device. 4. A pressure monitoring device at the outer periphery of the runner chamber is provided as a water level detecting device for detecting that the water level in the runner chamber is below the lower end of the runner, and the water level in the runner chamber is below the lower end of the runner. After the fact is detected by the pressure monitoring device due to the sudden decrease in the pressure of the outer peripheral portion of the runner chamber, the first automatic valve of the first air supply pipe provided in the runner chamber is fully closed, and the first suction valve provided in the upper suction pipe is closed. 2. The air supply operation is performed by keeping the air supply pipe open and further pushing down the water level.
A method for operating the pumped storage power generation apparatus described. 5. A first automatic valve of a first air supply pipe provided in the runner chamber and a second automatic valve provided in an upper suction pipe downstream of the runner chamber.
The second automatic valve of the air supply pipe is fully opened to send air into the runner chamber, and the water level in the runner chamber is below the lower end of the runner. The pumping operation according to claim 1, wherein the valve is fully closed, the second automatic valve of the second air supply pipe provided in the upper suction pipe is fully opened, and the water level is further pushed down to perform air operation. How to operate the generator.