JPH02294566A - Pelton water turbine - Google Patents

Abstract

PURPOSE:To perform safe and reliable the restarting and reparalleling of a water turbine by providing a deflector opening correcting device to correct the opening of a deflector based on the size of a jet discharged from a needle valve and the number of needle valve discharge operation times. CONSTITUTION:A deflector opening correcting device 39 inputs a restarting command 40 and needle valve opening commands 42 and 43 inputted from the outside to correct a signal from a load limiting device 41 for a deflector according to a jet size. A deflector opening correcting device 44 corrects a signal from a load regulating device 46 when reparalleling is effected in a no-load state after continuance of operation and is worked by inputting a reparalleling command 45 and the needle valve opening commands 42 and 43 from the outside. Since correction of a deflector and correction of gain for a deflector can be arbitrarily performed, this constitution performs the safe and reliable restarting and reparalleling of a water turbine.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to Pelton water turbines, and is particularly applicable to power plants that are obligated to discharge water downstream by omitting spillways. The present invention relates to a Pelton water turbine suitable for parallel entry and a control device thereof.

[Conventional technology]

As described in Japanese Patent Application Laid-Open No. 63-113183, the conventional device adjusts the amount of water input to the water turbine using a deflector controlled by an input water amount control device, and controls the rotation speed and output of the water turbine. On the other hand, the needle valve was controlled by a discharge control device, making it possible to control the deflector opening according to the discharge amount. Generally, Pelton turbines are impulse turbines that are applied to high-head sites, and horizontal and vertical shaft types are adopted.

The outline will be explained below using the horizontal axis Pelton turbine shown in Figure 3. Pressure water from the penstock 10 is distributed to two nozzles 1 and 2 through inlet curved pipes 11a and 1lb.
2 and become high-speed jets 12a and 12b, which add water power to the packet 5a and do work. It is discharged into the lower waterway 14. During normal operation, the needles la and 2a in the respective nozzles 1 and 2 are driven by their respective needle servo motors lc.
, 2c are opened and closed according to the load, and the flow rate is adjusted. Deflectors lb and 2b are rotatably provided between the nozzles 1 and 2 and the runner 5, and are rotatably supported by the nozzles, and when the load suddenly decreases or a failure occurs, the servo motor 6, the respective deflectors lb and 2b are moved and rotated simultaneously via the link mechanism 7, thereby deflecting the direction of the jet from the direction of the packet 5a and suppressing an increase in the number of rotations of the water turbine.

On the other hand, from the perspective of cost reduction, various studies have been carried out on eliminating the spillway, which is a waterway that bypasses the turbine and discharges water, in order to discharge surplus water generated by an accident or load shedding downstream of the turbine in Pelton turbines. ing. In order to satisfy this requirement, (1) the deflector continues to discharge water downstream during the turbine stop operation and for a certain period of time after the turbine is stopped until the water intake gate is fully closed; (2) If the accident is restored before the water intake gate is closed, the turbine will be restarted and re-entered while water continues to flow. There is a need for such things.

A conventional technique for this purpose will be explained using FIG. 4.

In FIG. 4, reference numeral 18 denotes an input water amount control device, which controls the deflector 1b with a control signal 20 and adjusts the rotational speed of the water wheel 17 by inputting water to the water wheel 17. It is possible to start and re-enter. 19 is a discharge control device, which controls the needle valve 1a with a control signal 22. 24 is a deflector opening control signal supplied from the discharge control device 19 to the deflector 1b, and this signal makes it possible to control the deflector lb to an appropriate opening according to the discharge amount by the needle valve 1a. There is. [Problem to be Solved by the Invention] However, in the above-mentioned conventional technology, since the deflector is controlled only by the discharge amount, there is no problem when there is only one needle valve 1a, but generally there is an even number of needle valves, i.e. It is normal to have 2, 4, or 6 needle valves, and in order to improve efficiency, there are cases where the number of needle valves used is changed to 1 or 2 instead of all the needle valves.
If the opening signal of the deflector 1b is output only when the water is discharged, for example, the diameter of the jet water discharged from the needle valve is different between one needle valve and two needle valves even if the water discharge is the same, so the diameter of the jet water discharged from the needle valve is naturally different. If the opening of the deflector was determined only by the opening of the deflector, the deflector would open too much, which could lead to an increase in the rotational speed of the water turbine, making normal control difficult and posing a safety problem.

Furthermore, since the conventional Pelton turbine has two flow adjustment mechanisms, the deflector 1b and the needle valve 1a, the flow rate input to the turbine becomes a two-variable function of the deflector and the needle valve, which interfere with each other's control systems. Since the collision stability is likely to be impaired, the deflector position is adjusted in advance as shown in Figure 5.
A control method is adopted in which the needle valve is operated after c is opened in advance to a position d that does not inhibit the diesel engine l-e, and the flow rate is treated as a one-variable function of the needle.

However, in the above conventional technology, the amount of water flowing into the water turbine is a function of two variables, the deflector and the needle valve, and it is considered difficult to maintain the same speed at the rated rotation speed. Furthermore, there is a problem in that stability is likely to be impaired due to interference with each other's control systems.

The purpose of the present invention is to solve the above-mentioned problems in a Pelton turbine without a spillway, and to perform discharge control and water inflow control required for a Pelton turbine without a spillway.
The objective is to provide a Pelton water turbine and its control device that can be operated safely and reliably. [Means for solving the problem] The above purpose is to provide a deflector that is equipped with a deflector and a needle valve, and uses the diameter of the jet discharged from the needle valve and the number of discharge operations of the needle valve as variables to uniformly control the rotational speed of a water turbine generator. A deflector opening correction device that corrects the opening of the water turbine and appropriately adjusts the amount of water input to the turbine, and a needle valve that stops the needle valve at any position and maintains the needle valve at a constant opening, that is, the amount of water discharged. This can be achieved by providing a locking device and a deflector control gain correction device that corrects the deflector control gain depending on the operation mode of the water turbine.

Similarly, the variables of the deflector opening correction device are the needle valve opening and the number of needle valve discharge operations. Alternatively, the above objective can be similarly achieved by the water tank water level and the number of needle valve discharge operations, or by the iron pipe water pressure and the number of needle valve discharge operations.6 [Operation] According to the above configuration, the water turbine can be restarted in the discharge operation state by the deflector. If a command is issued, deflector control gain supplement iE
"A" position is automatically switched to the re-entry gain. As a result, firstly, the deflector interval IJ+i8 return signal is changed to the position where the deflector does not obstruct the jet water, and then
Since the gain is switched from the feedback signal during normal operation that opens the needle valve to the feedback characteristic where the deflector opening and feedback signal are determined on a one-to-one basis, the deflector opening can be freely controlled from fully open to fully idle. This makes it possible to freely control the rotational speed and output of the water turbine.

Also, since the deflector opening command value and the deflector opening deviation gain are switched at the same time, the gain can be adjusted to be the same as the gain of the control system before switching the deflector opening feedback signal gain described above. will not cause instability of the control system.

Next, during discharge operation, the needle valve is controlled to any position manually or by the water tank water level, so the diameter of the jet output from the needle valve can also be any diameter. The deflector opening degree correction device, which is one of the present inventions, has a built-in relationship between the jet diameter, the number of needle valve discharge operations, and the deflector no-load opening degree, and provides a positional signal between the startup times of the load limiting device when restarting the water turbine. Since this is corrected by inputting the jet diameter and the number of needle valve discharge operations, the water turbine can be started safely and reliably no matter where the needle valve is located. In addition, even if the water turbine is not stopped in the event of an external failure and continues to operate at the rated rotation under no-load conditions, the no-load opening degree is similarly corrected, so no matter what position the needle valve is in, it can be done safely and reliably. It becomes possible to continue operating the water turbine in an unloaded state.

Furthermore, since the needle valve locking device stops the needle valve at an arbitrary position when re-entering the water turbine, the amount of water input to the water turbine can be treated as one variable by the deflector, making it easy to connect the water turbine to the system without interfering with the control system. Can be re-entered.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG. still,
Structural parts that are the same as the conventional example are marked with the same symbol } and their explanation will be omitted. In FIG. 1, 25 is a gain correction device n for the deflector opening feedback signal, and a restart command 26 input from the outside.
Therefore, after the feedback A during normal control, that is, after the deflector has opened in advance to a position where it does not obstruct the jet water, the deflector opening degree and the feedback signal are determined by a one-to-one ratio from the signal gain that opens the needle valve to the feedback signal. Switch the gain.

After the deflector distance command signal 31 is gain-adjusted by the output amplifier 29, a deviation signal 34 with respect to the deflector feedback signal 33 is calculated.

After the deflector opening degree deviation signal 34 is gain-adjusted again by the output booster 30, it is sent to the E/M converter 35, and then the deflector pressure distribution valve 36 and the deflector servo motor 37.
Finally, the deflector 38 is controlled via.

The gain correction device 27 for the deflector opening command signal and the gain correction device 28 for the deflector opening deviation signal adjust their gain in conjunction with the gain correction device 25 for the deflector opening feedback signal in response to the restart command 26 input from the outside. Switch.

The deflector opening correction device 39 receives a restart command 40 and needle valve opening commands 42 and 43 input from the outside, and corrects the signal of the deflector load limiting device 41 in accordance with the jet diameter. The deflector opening degree correction device 44 corrects the signal of the load adjustment device 46 when re-entering the vehicle after continued operation in a no-load state, and is configured to correct the signal of the load adjusting device 46 when re-entering the vehicle after continued operation in a no-load state, and receives a re-entering command 45 and a needle valve opening command input from the outside. It operates using 42 and 43 as inputs.

The needle valve locking devices 47a and 47b stop the needle valves at arbitrary positions in response to a needle valve lock signal 48 input from the outside. Next, a series of operations from water turbine operation to discharge operation using a needle valve and reparalleling using a deflector will be explained with reference to FIG.

In FIG. 2, A is a state in which a water east stop command is issued due to an external failure while the water turbine is in operation, and the parallel circuit breaker is opened under the conditions of A and the water turbine is disconnected from the system. Water turbine stop command A
Under condition B in which the parallel circuit breaker is opened, the deflector 38 and load limiting device 41 shown in FIG.

Next, there is a state D in which the field breaker is open as shown in FIG. 2, and a state E in which the deflector 38 is completely idle as shown in FIG. 1, which is one of the features of this embodiment. Deflector opening feedback signal gain correction device 25, deflector opening 31 and opening deviation (gain correction devices 27 and 28 of No. 34 operate, and deflector opening feedback signal 33 has a one-to-one ratio between the deflector opening degree and the feedback signal. The gain changes to the characteristics determined by .

Naturally, when the gain is switched, the gain of the entire control system changes, and there is a possibility that the control system becomes unstable. However, in this embodiment, the gain correction devices 27 and 28 operate in conjunction with each other to adjust the gain of the entire control system. Since it is always kept constant, it never becomes unstable.

Similarly, in the state E, the deflector opening correction devices 39 and 44 operate, and the deflector no-load opening corresponding to the current jet diameter is determined by the current needle valve jet diameter signal and discharge operation number signals 42 and 43. The load limiting device 41 and the load adjusting device 46 are corrected.

The state in which the deflector gain correction and deflector opening correction described above have been completed is the state shown in Fig. 2 F. In this state, the water turbine is in a stable operating state at the rated rotational speed by the various correction devices described above, and the required water volume is maintained. In this state, a re-entry command is input from the outside, which is state G. If the main engine rotational speed is above the limit value in this state, the needle valve chain shown in Fig. 1 is activated. Lock devices 47a, 47
Lock b to fix the needle valve opening.

Therefore, since the flow rate flowing into the water turbine depends only on the opening degree of the deflector, the speed is made uniform by the speed equalization device command, and the water 11[
can be easily reparalleled into the system.

The state in which it is reparalleled to the system is I, and on the condition that it is paralleled, the needle valve locking system ii! ! 4. 7 a, 4
7b and return the needle valve to normal operating condition.

At the same time, the load limiting device is opened, and on the condition that the deflector-needle characteristic circuit output signal based on the load limiting position signal becomes equal to the signal from the discharge amount tA regulator 51, the load limiting device is stopped, and the deflector gain is Release the correction device and return to normal operating condition.

In addition, in FIG. 1, the same effect can be obtained by replacing the jet diameter signals 42 and 43 with the iron pipe water pressure signal and needle opening signal.

〔Effect of the invention〕

According to the present invention, deflector correction and deflector gain correction can be made arbitrarily, especially in a Pelton turbine that does not have a spillway, so restarting and re-entering the turbine from a discharge operation state using a needle valve can be done safely and reliably. It has the effect of being possible.

Also, when re-paralleling to the grid, the needle valve can be locked #1, so the amount of water flowing into the water turbine can be treated as one variable.
This has the effect of facilitating reparalleling to the grid.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of a control device for a Pelton turbine according to an embodiment of the present invention. Figure 2 is a block diagram showing the sequence of operation control, Figure 3 is a longitudinal sectional view showing the general appearance of a Pelton turbine, Figure 4 is a configuration diagram of a conventional control device, and Figure 5 is a diagram of the deflector and needle valve jet. It is a deflector-needle valve relationship diagram showing the relationship. 25... Deflector feedback signal gain correction device, 27.
28...Deflector opening degree gain correction device, 38...
Deflector, 39...Opening degree correction device for load limiting device, 44...Load m! 1′! Arlm opening correction device, 47a, 47b・
...Needle valve locking device, 49...High signal selector, 5
1... Discharge amount regulator.

Claims (1)

[Scope of Claims] 1. In a Pelton turbine equipped with a deflector and a needle valve, in which the amount of water input to the turbine and the amount of water discharged can be controlled by the deflector and the needle valve, the diameter of the jet discharged from the needle valve and A Pelton water turbine characterized in that a deflector opening correction device is provided for correcting the opening of the deflector based on the number of needle valves in discharge operation. 2. In a Pelton water turbine that is equipped with a deflector and a needle valve, and in which the amount of water input to the turbine and the amount of water discharged can be controlled by the deflector and the needle valve, the diameter of the jet discharged from the needle valve and the number of needle valve discharge operations a deflector opening degree correction device that corrects the opening degree of the deflector based on the opening degree of the deflector, a needle valve locking device that stops the needle valve at an arbitrary opening degree, and a deflector that corrects the control gain of the deflector according to the operation mode of the water turbine. A Pelton water turbine characterized by being provided with a control gain correction device. 3. In a control device for a Pelton turbine, which includes a deflector and a needle valve, and is capable of controlling the amount of water input to the turbine and the amount of water discharged by the deflector and the needle valve, the diameter of the jet discharged from the needle valve and the discharge from the needle valve A deflector opening degree correction device is provided that corrects the opening degree of the deflector using the number of operations as a variable, and based on a correction signal from the deflector opening degree correction device, speed uniform control to the rated rotational speed of the water turbine is adjusted. A control device for a Pelton water turbine characterized by the following. 4. In a control device for a Pelton water turbine that includes a deflector and a needle valve, and is capable of controlling the amount of water input to the turbine and the amount of water discharged by the deflector and the needle valve, the diameter of the jet discharged from the needle valve and the discharge water from the needle valve A deflector opening degree correction device is provided that corrects the opening degree of the deflector using the number of operations as a variable, and based on a correction signal from the deflector opening degree correction device, adjusting speed uniform control to the rated operating speed of the water turbine. A control device for a Pelton water turbine, characterized in that a needle valve locking device for stopping the needle valve at an arbitrary opening degree is provided, and the amount of water discharged by the needle valve is made constant based on the needle valve locking device. 5. In a control device for a Pelton water turbine, which includes a deflector and a needle valve, and is capable of controlling the amount of water input to the water turbine and the amount of water released from the water turbine, the diameter of the jet discharged from the needle valve and the amount of water discharged from the needle valve. A deflector opening degree correction device is provided that corrects the opening degree of the deflector using the number of operations as a variable, and based on a correction signal from the deflector opening degree correction device, adjusting speed uniform control to the rated operating speed of the water turbine. , a needle valve locking device is provided to stop the needle valve at an arbitrary opening degree, and based on the needle valve locking device, the amount of water discharged by the needle valve is kept constant, and the control gain of the deflector is adjusted to the control gain of the water turbine. A control device for a Pelton water turbine, characterized in that it is provided with a deflector control gain correction device that corrects it depending on the operation mode. 6. A method for controlling a Pelton turbine comprising a deflector and a needle valve, in which the amount of water input to the turbine and the amount of water discharged from the turbine can be controlled by the deflector and the needle valve, the diameter of the jet discharged from the needle valve and the discharge from the needle valve. Adjusting the uniform speed control of the water turbine to the rated operating speed based on a correction signal that corrects the opening degree of the deflector using the number of operations as a variable, and correcting the control gain of the deflector according to the operation mode of the water turbine. A method for controlling a Pelton water turbine, characterized in that the needle valve is stopped at an arbitrary opening degree to make the amount of water discharged by the needle valve constant.