JP2695967B2 - Phase control of hydraulic machine - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a phase control operation control device used for a hydraulic machine such as a water turbine that performs phase control operation.

[Prior Art] Some hydraulic machines such as a water turbine used in a hydroelectric power station perform a phase-shift operation. The purpose of this phase adjustment operation is to adjust the reactive power of the power system by rotating the water turbine in the air with power from the system. FIG. 4 shows a control sequence at the time of the phase adjustment operation of the hydraulic machine performing the phase adjustment operation. When a start command of the phase adjustment operation is issued, the inlet valve is opened (step 100). After detection of the full opening of the inlet valve (step 101), the guide vane is opened (step 102) and the runner is rotated (step 103). When the rotational speed of the water turbine is controlled by the governor to reach the rated speed and matches the frequency of the system, the generator is inserted into the system (step 104).

Since the opening of the inlet valve is driven by oil supply from the hydraulic tank to the servomotor, the oil pressure in the pressure oil tank drops according to the valve opening operation of the inlet valve (step 105). A drop in the hydraulic pressure of the pressure oil tank is detected, and in response to this detection, the pressure oil pump is operated to supply oil to the pressure oil tank (step 106).

After the generator is inserted, the guide vane is closed to cut off the water flow (step 107). After the guide vane is fully closed (step 108), the compressed air is introduced into the runner chamber to push down the water surface in the runner chamber to discharge water (step 109), and the water wheel is idled to perform phase adjustment operation. After the guide vanes are fully closed, oil is supplied from the hydraulic tank to the servomotor to close the inlet valve (step 110).

The hydraulic oil tank that supplies hydraulic oil to the servo motor for opening and closing the inlet valve opens and closes the control hydraulic pressure in order to prevent the hydraulic oil system from becoming too large and improve reliability with the increase in the capacity of the hydraulic machine. In many cases, it is installed separately from the pressure oil tank of the oil device.

[Problems to be Solved by the Invention] However, in the hydraulic machine that performs the phase adjustment operation, when the phase adjustment operation is started, the pressure oil tank sends the pressure oil to the servo motor twice to open and close the inlet valve. Must be supplied. For this reason, the pressure oil tank needs a large capacity,
This has a problem that the construction cost of the hydroelectric power plant and the maintenance and management cost of the pressure oil device for the inlet valve are greatly increased.

Therefore, an object of the present invention is to provide a phase adjustment operation control device of a hydraulic machine that can reduce the capacity of a pressure oil tank for an inlet valve.

Means for Solving the Problems In order to achieve this object, the present invention provides an inlet valve, a pressure oil tank, and a servomotor that opens and closes the inlet valve with pressure oil supplied from the pressure oil tank. A pressure oil pump for supplying pressure oil to the pressure oil tank, and after opening the inlet valve and opening the guide vane to start a hydraulic machine and insert a generator into the system, the guide vane Closing the inlet valve and performing the phase adjustment operation by closing the inlet valve, wherein the phase adjustment operation control device for the hydraulic machine detects that the pressure of the pressure oil tank has become equal to or less than a first predetermined value, and Pressure detecting means for activating the pressure oil pump, detecting that the pressure in the pressure oil tank has recovered to a second predetermined value by the activation of the pressure oil pump, and generating a recovery signal; and closing the guide vane. Detection and generates a closing signal Guide vane closing detection means, and control means for supplying the pressure oil from the pressure oil tank to the servomotor and closing the inlet valve when both the recovery signal and the closing signal are generated; and It is characterized by having.

[Operation] The pressure oil tank supplies pressure oil to the servomotor for the opening operation of the inlet valve. When the pressure of the pressurized oil tank falls below the first predetermined value due to this refueling, the pressure is detected by the pressure detecting means, and the pressurized oil pump is started to replenish the oil in the pressurized oil tank.

After opening the guide vanes, rotating the turbine, and inserting the generator, the guide vanes are closed. When the guide vane closing detecting means detects that the guide vane is closed, it generates a closing signal. When the pressure of the pressurized oil tank recovers to the second predetermined value by the replenishment of the oil by the pressure oil pump, the pressure detecting means detects this and generates a recovery signal.

When both the closing signal and the recovery signal are generated, the control means supplies pressure oil from the pressure oil tank to the servomotor to close the inlet valve.

Since the closing of the inlet valve is performed not only when the guide vane close signal is generated but also when the pressure oil tank pressure recovery signal is generated, that is, after the oil pressure in the pressure oil tank is restored, the capacity of the pressure oil tank is increased. 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 the generator 4 is connected to a power system 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 a servo motor
Opening and closing of the inlet valve 9 is detected by an inlet valve detection switch 11. The servomotor 10 is driven by pressure oil from a pressure oil tank 13 via a pressure distribution valve 12. The pressure oil pump 14 supplies the 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. The pressure relay 15 generates a pump start signal when the oil pressure of the pressure oil tank 13 becomes equal to or lower than the normal minimum oil pressure, and generates a pump stop signal when the oil pressure becomes equal to or higher than the normal maximum oil pressure. The pump start signal and the pump stop signal are input to a pressure oil pump control device (not shown) to start and stop the pressure oil pump 14 to control the intermittent operation. The pressure relay 16 determines that the oil pressure in the pressure oil tank T is a predetermined value P1,
Specifically, when it is detected that the inlet valve 9 is normally operable hydraulic pressure value P1 or more that can normally drive the inlet valve 9 by the servo motor 10, a recovery signal is generated and the control device 17
To send to.

The control device 17 includes a guide vane closing detection switch 7
The pressure distribution valve 12 is closed when the closing signal from the guide vane closing detection switch 7 and the recovery signal from the pressure relay 16 are input together. The closing operation of the pressure distribution valve 12 sends the pressure oil from the pressure oil tank 13 to the servomotor 10 to close the inlet valve 9. The air tank 18 injects compressed air into the runner chamber 1 through the air supply valve 19.

Next, the operation of this embodiment will be described with reference to FIGS.

When the start of the phase adjustment operation is instructed, the pressure distribution valve 13 is opened and the pressure oil from the pressure oil tank 13 is supplied to the servomotor 10 to open the inlet valve 9 (FIG. 2, step 20). With the supply of the pressure oil from the pressure oil tank 13 to the servomotor 10, as shown in FIG. 3, when the oil pressure of the oil tank 13 drops below the normal minimum oil pressure (step 21), the pressure relay 15 When this is detected, a pump start signal is generated, and the pressure oil pump 14 is started to supply the oil in the oil collection tank T to the pressure oil tank 13 (step 22).

When the inlet valve 9 is fully opened, the inlet valve detecting 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 governor (not shown). (Step 24). As a result, the pressurized water flows into the runner 2 from the upper pond U, rotates the runner 2 (step 25), and flows out to the lower pond V. When the rotation of the runner 2 rises and reaches a predetermined speed, the guide vane 8 is closed to the no-load opening, and the speed governing operation of the governor is started to control the rotation speed of the guide vane 8 to the rated speed. Then, when the frequency matches the frequency of the system 6, the generator 4 is inserted into the system 6 by the circuit breaker 5 (step 26).

Immediately after this insertion, the guide vanes 8 are closed (step 27), and when the guide vane closing detection switch 7 detects that the guide vanes 8 are fully closed (step 28), a closing signal is sent to the control device 17. When the water flow is cut off by the full closure of the guide vanes 8, the air supply valve 19 injects the compressed air in the air tank 18 into the runner chamber 1 to remove water around the runner 2 (step 29). Spin and start the phase adjustment operation.

The hydraulic pressure of the hydraulic oil tank 13 gradually increases due to the operation of the hydraulic oil pump 14 in step 22 and the hydraulic pressure value P1 at which the inlet valve can operate normally.
Is reached, 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, the control device 17 responds to the input of the recovery signal to control the pressure distribution valve 12.
Is closed. As a result, the servo motor 10 closes the inlet valve 9 by the hydraulic pressure of the pressure oil tank 13 (step 3).
1).

Thereafter, when the pressure oil tank 13 reaches the maximum service oil pressure, the pressure relay 15 detects this and generates a pump stop signal to stop the operation of the pressure oil pump 14.

As described above, the pressure oil tank 13 supplies oil to the servo motor 10 to open the inlet valve 9, and after the oil pressure decreases, a recovery signal is generated even if a guide vane closing signal is generated. Is not supplied to the servomotor 10 until the hydraulic pressure is sufficiently recovered. Therefore, the pressure oil tank 13 can be significantly reduced in size as compared with a conventional hydraulic machine.Also, even if this small-capacity pressure oil tank 13 is used, the time from the opening of the inlet valve to the start of the phase adjustment operation can be reduced. Can be performed as quickly as conventional hydraulic machines.

In the above embodiment, the guide vanes 8 were fully closed in step 27. However, in step 27, the guide vanes 8 may be slightly opened without being fully closed. Therefore, in this specification, the closing of the guide vanes includes both the fully closed and the small opened.

[Effects of the Invention] As is clear from the above description, according to the present invention, it is detected that the pressure of the pressure oil tank has become equal to or less than the first predetermined value, and the pressure oil pump is started up. Pressure detecting means for detecting that the pressure of the pressurized oil tank has recovered to the second predetermined value by the activation of the oil pump and generating a recovery signal, and a guide vane for detecting the closing of the guide vane and generating a closing signal. A closing detection means, and a control means for supplying pressure oil from the pressure oil tank to the servomotor to close the inlet valve when both the recovery signal and the closing signal are generated. The valve closing is performed not only when a closing signal is generated but also when a recovery signal is generated, that is, after the hydraulic pressure of the hydraulic oil tank is recovered, so that the capacity of the hydraulic oil tank can be reduced. Reduce the maintenance and management costs of the pressure oil device for the inlet valve It can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an embodiment of a phase control operation device for a hydraulic machine according to the present invention, FIG. 2 is a sequence diagram showing a control sequence of the above embodiment, and FIG. FIG. 4 is a timing chart showing the operation of the members, and FIG. 4 is an explanatory diagram showing a control sequence of a conventional phase control operation control device for a hydraulic machine. 4 ... generator, 6 ... system, 7 ... guide vane closing 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)

(57) [Claims] An inlet valve, a pressure oil tank, a servomotor for opening and closing the inlet valve with pressure oil supplied from the pressure oil tank, and a pressure oil pump for supplying pressure oil to the pressure oil tank. After starting the hydraulic machine by opening the inlet valve and opening the guide vane and inserting the generator into the system, the guide vane is closed and the inlet valve is closed to adjust the phase. In the phase adjustment operation control device of the hydraulic machine that performs the operation, the pressure oil tank detects that the pressure of the pressure oil tank has become equal to or less than a first predetermined value, and starts the pressure oil pump,
Pressure detecting means for detecting that the pressure of the pressure oil tank has recovered to the second predetermined value by the activation of the pressure oil pump and generating a recovery signal, and detecting the closing of the guide vane and generating a closing signal. Guide vane closing detecting means that is generated, and control means for supplying the pressure oil from the pressure oil tank to the servomotor and closing the inlet valve when both the recovery signal and the closing signal are generated. A phase adjustment operation control device for a hydraulic machine, comprising: