JPH0458276B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to variable speed pumping equipment, and more particularly to control of start-up and load adjustment.

[Conventional technology]

In a pumped storage power generation system, the load (input power)
For adjustment, research has been conducted on using an induction machine with secondary excitation as the rotating electric machine and operating it at variable speed. For example, the 1981 National Conference of the Institute of Electrical Engineers of Japan Paper No.
Although the principle is described in 553 ``Variable Speed Operating Characteristics of Large-Capacity Synchronous Motor,'' no specific control method has been proposed.

On the other hand, regarding the control method of variable speed pumping equipment,
As described in Japanese Unexamined Patent Publication No. 48-21045, there is a method of controlling a pump water turbine to a rotation speed corresponding to an input power command value using a variable speed drive device. According to this control method, when the rotational speed is constant, operation according to the input power command value can be realized by ignoring the error of the rotational speed command generator. However, when the input power command value is changed to adjust the load, for example, when the input command value is increased, the rotation speed command value increases and the pump-turbine is accelerated, but the inertial energy at this time is supplied by the drive device. Therefore, during a transient state, it is not possible to make the actual input power accurately follow the input power command value, and it is not possible to perform precise load adjustment.

As a control method to solve this problem, JP-A-61
- As described in the specification and drawings of No. 170299,
The drive device is controlled so that the deviation of the actual input power from the input power command value is zero, and the pump is controlled in accordance with the command value from the optimal guide valve opening generator which inputs the actual operating rotation speed. A method has been proposed for controlling the opening and closing of the guide valve of a water turbine.

[Problem that the invention seeks to solve]

According to the above-mentioned control method, precise load adjustment is possible during pumping operation, but the control method for smoothly controlling start-up and operation from a stopped state to pumping operation is still unclear. Not proposed.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to propose a variable speed water pumping device that can stably operate the device in each operation mode and can perform fine load adjustment during pumping operation.

[Means for solving problems]

The present invention provides a control device that controls a power conversion device for controlling a rotating electric machine of a variable speed drive device that drives a pump-turbine, and a speed detection value output from a speed detector that detects the rotational speed of the pump-turbine. A first control signal for outputting a first control signal for controlling the power converter so that the deviation of the speed command value becomes zero.
and the power conversion device so that the deviation between the active power detection value output from the power detector that detects the active power supplied to the variable speed drive device from the power system and the active power command value becomes zero. a second control means for outputting a second control signal for controlling the first control signal; a logic means for inputting a pumping operation determination condition; and a second control means for inputting a pumping operation determination condition; The present invention is characterized in that a switching means is provided for selectively applying the control signal to the power conversion device.

[Effect]

The logic means determines the success or failure of the pumping operation condition from the input signal, applies a first control signal to the power converter until the condition is satisfied, and applies a second control signal to the power converter after the condition is satisfied. Control the switching means. As a result, the speed of the variable speed drive device that drives the pump turbine is controlled by this power conversion device to match the speed command value until it enters the pumping operation state, and after entering the pumping operation state, the effective power Power is controlled to match the command value. Then, the initial value of the active power command value is determined and set from the pump rotation speed, pump head, etc. so that it is equal to the active power actually input to the variable speed drive device when the pumping operation condition is satisfied. Therefore, the variable speed pumping device is stably controlled from start-up to pumping operation, and during pumping operation, precise load adjustment is performed in accordance with the active power command value.

〔Example〕

FIG. 1 is a block diagram of a variable speed pumping device according to the present invention, showing an embodiment in which an AC excited synchronous machine is used as the rotating electric machine of the variable speed drive device.

A wound induction machine 2 connected to a power system 1 is rotated by AC excitation by a power conversion device 3 such as a cycloconverter, and drives a pump water turbine 4 . The power conversion device 3 controls the AC excitation current according to the phase command signal to increase or decrease the output of the wound induction machine 2. The phase command signal is a first phase command signal output from the speed controller 6 in order to adjust the deviation between the rotational speed N detected by the speed detector 5 and the rotational speed command value _N0 to zero. , the active power P supplied from the power system to the wound induction machine 2 detected by the power detector 7, and the active power command value given from the outside.
A second phase command signal output from the power controller 8 is selectively applied to adjust the deviation of P ₀ to zero.

On the other hand, a guide valve controller 9 that opens and closes a guide valve (not shown) of the pump turbine 4 receives an opening command signal Y ₀ outputted from a pump characteristic function generator 10 based on the rotational speed N and head signal H. controlled by

The starting power converter 11 is connected between the power system 1 and the wound induction machine 2 via the switch 12, and when the wound induction machine 2 is started, the wound induction machine 2 changes from the stopped state to the power converter. This is controlled until the rotational speed range is determined by the rated output voltage, etc. of No. 3.
For this purpose, the switch 12 is closed at the start of startup operation and opened when the wound induction machine 2 is accelerated to a set value N ₀ near the lowest value of the rotational speed range. At this time, the switch 13 is closed and the wound induction machine 2 enters AC excitation operation, and the switch 13 is opened when the pumping operation is stopped.

When the wound induction machine 2 starts AC excitation operation in this manner, the switching device 15 controlled to open and close by the logic device 14 is in a closed state, and the switching device 16 is in an open state. Speed controller 6
The wound induction machine 2 is controlled to have a constant value equal to the rotational speed command value N ₀ of the pump water turbine 4. In this state, the command to push down the water surface of the pump turbine 4 is released, and the water pressure for pumping water pricing is established. The switching device 17 is closed on the condition that the establishment of water pressure is confirmed by the pressure switch, and the guide valve is opened to the opening set value Ys output from the guide valve opening command pattern generator 18. When the pumping operation is started in this way and the pumping operation conditions are met, the logic device 14 operates and the switch 15
is opened, switch 16 is closed, and at the same time switch 1
9 and 20 are closed, and the switch 17 is opened. As a result, the power converter 3 is given the second phase command signal from the power controller 8, and the active power P input to the wound induction machine 2 is changed to the command value P ₀
is controlled so that it is equal to , and enters AFC operation.

An example of the logic device 14 is shown in FIG. The guide valve position detector 21 indicates that the guide valve opening degree Ya is the set opening degree.
When Ys is exceeded, the output signal OP becomes level "1". The speed stabilization detector 22 outputs a signal SA at level " ₁ " when the absolute value of the deviation ΔN of the rotational speed N from the command value _N0 is less than or equal to the set value N1. The signal ST input to the AND device 23 has a level of "1" when a pump load operation command is issued, and a level "0" when a stop command is issued. Logical sum device 24
is the output signal SA and the output signal of the AND device 23
SW is input, and its output signal is input to the AND device 23. When the output signal SW of the AND device 23 is at level "0", the switch 15 is closed and the switch 16 is closed.
is in an open state, and when the level is "1", the switch 15 is in an open state and the switch 16 is in a closed state.

By such a logic device 14, a switch 15,
16, the phase command signal given to the power conversion device 3 is switched from the speed controller 6 side to the power controller 8 side after checking the rotational speed deviation, so that the initial active power command P ₀ By setting the value in accordance with the input of the wound induction machine 2 determined by the pump rotational speed N and the head H, smooth operation can be continued at the time of control switching.

FIG. 3 shows a modification of the logic device 14. The output signal OP of the guide valve position detector 21 is the time
It is input to the AND device 26 via the delay circuit 25 of _T1 , and the output signal SW is generated by ANDing it with the pump load operation command ST. Said delay time T ₁
is set to allow a margin for the speed settling time by the speed controller 6 when the pump load fluctuates. In this way, the logic device 14 can be simplified without the speed settling detector.

FIG. 4 shows an embodiment in which a DC excited synchronous machine is used as the rotating electrical machine of the variable speed drive device. Components that are the same as those of the embodiment shown in FIG. 1 are given the same reference numerals, and detailed explanation thereof will be omitted.

The power conversion device 29 that supplies power from the power system 1 to the synchronous machine 27 has its output frequency controlled by the output signal from the phase detector 28 directly connected to the synchronous machine 27, and the output frequency is controlled by the output signal from the speed controller 6. First
The output power is controlled by the phase command signal and the second phase command signal output from the power controller 8, and the shaft output of the synchronous machine 27 is increased or decreased. The acceleration pattern generator 30 outputs a speed command signal from the stopped state to the set speed N ₀ at the start of pumping operation, and the speed controller 6 calculates the deviation between this speed command signal and the speed signal output from the command detector 5. A first phase command signal is given to the power conversion device 29 to control the synchronous machine 27 so that the phase becomes zero, thereby giving the power conversion device 29 a startup control function. After the pump turbine 4 reaches the set speed N ₀ , water surface pressure is released and AFC operation is then started in the same manner as described above.

In addition to this modification, the switchers 15 and 16 are omitted and both controllers 6 and 8 are left connected to the power conversion devices 3 and 29, so that the output of the logic device 14 is used as the output of both controllers 6 and 8. It is also possible to relatively change the gain.

〔Effect of the invention〕

The present invention logically judges the pumping operation conditions to control the speed or power of the rotating electric machine.
Control from startup to pumping operation becomes stable, and precise load adjustment is possible during pumping operation.

[Brief explanation of drawings]

The drawings show embodiments of the present invention, and FIGS. 1 and 4 are overall block diagrams, and FIGS. 2 and 3 are block diagrams.
The figure is a block diagram of a logical device. DESCRIPTION OF SYMBOLS 1...Power system, 2...Wound induction machine, 3...Power converter, 5...Speed detector, 6...Speed controller, 7...
Power detector, 8... Power controller, 14... Logic device,
15, 16...Switcher.

Claims (1)

[Claims] 1. A variable speed drive device having a rotating electrical machine, a power conversion device that connects the rotating electrical machine to a power system, a pump water turbine rotationally driven by the variable speed drive device, and a speed detector that detects the rotational speed of the pump water turbine. and a power detector that detects active power supplied to the variable speed drive device from the power system, and controls the power conversion device by inputting an output signal from the speed detector and an output signal from the power detector. In the variable speed pumping device, the control device controls the power conversion device so that the deviation between the speed detection value outputted from the speed detector and the speed command value becomes zero. a first control means for outputting one control signal; and a second control means for controlling the power converter so that a deviation between an active power detection value output from the power detector and an active power command value becomes zero. a second control means for outputting a control signal;
A logic means for inputting a pumping operation determination condition, and a switching means for selectively applying the first control signal and the second control signal to the power conversion device based on an output signal from the logic means. Features a variable speed pumping device.