JPS58182500A - Controlling unit for dynamotor operation - Google Patents

Abstract

PURPOSE:To prevent an abnormal rise in the voltage/frequency ratio by a method wherein a hydraulic turbine and a dynamotor are put out of operation in an emergency action and a voltage at the dynamotor terminals higher than a prescribed value causes the exciting current to be interrupted when input is lost. CONSTITUTION:When input is interrupted while a dynamotor 1 is in operation as a synchronous motor, an input loss detector 12 is activated, yielding an emergency stop directive. The hydraulic turbine is stopped and parallellism-forming breaker 4 is opened. Failure of the breaker 4 to open causes a field breaker 9 to remain closed, when voltage across the terminals of the hynamotor is maintained at a rated value by means of an automatic voltage regulator 6. Under such conditions, a voltage detecting relay 14 stays in operation, which, after the elapse of a prescribed period of time, causes a gate shut-off directive to be supplied to the automatic voltage regulator 6, which in turn stops an exciting rectifier 8 from controlling the gate.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an operation control device for a generator motor, and in particular to an operation control device suitable for preventing overexcitation when a generator motor operated in series with a power grid is stopped due to input loss. i
Regarding the II device.

[Technical background of the invention and m points therebetween]

Regarding the stopping method when the generator motor loses input while operating as a synchronous motor, the method using the conventional control device is #
Please refer to the diagram! 19 □ Generator motor 1#i is operating in parallel to the power system through high voltage interrupter 2, main transformer 3, and interrupter 8a4. The excitation device includes an instrument transformer 5, an automatic voltage 14M generator 6, an excitation transformer 7 as an excitation power source, an excitation rectifier 8 that turns the excitation power source 1-by a signal from the automatic voltage 14M generator 6, and a field interrupter. 9, and an instrument transformer 10 for detecting input as an input detection device, an instrument current transformer ] 1 and an input loss detector 12.
It is usually composed of

Now, when the generator motor 1 loses input and the main engine is to be brought to an emergency stop, the emergency stop command is used to stop the control of the water tank (not shown) and at the same time open the interruption 4iS4 in parallel, thereby cutting off the field. By opening the generator motor 9 and cutting off the excitation current in the field a (b) path 13 of the generator motor l, the main engine can be stably stopped by reducing the speed of the main engine.

However, if the generator 1 loses its input and the parallel circuit breaker 4 becomes inoperable when it should open for some reason, the speed of the turbine's generator motor I Vi rapidly decreases due to the loss of input, and it stops. However, since the parallel breaker 4 does not open, the field breaker 9 also does not open. On the other hand, the automatic voltage regulator 6 maintains the terminal voltage of the generating WL motor 1 at the rated value.

(1) Excessive current flows through the field circuit, causing damage to the equipment and shortening the life of the collar.

(2) The terminal voltage and speed of the generator motor become large, causing the equipment to become over-excited, resulting in insulation deterioration due to temperature rise.

This situation will be explained with reference to FIG. Input loss points 30
Until now, the main engine has maintained its rated value, but the above-mentioned 15? When the generator motor 1 loses input as shown in the figure, the input loss point 3
The speed of the main engine decreases by 31Fi from 0. However, since the terminal voltage 32 of the generator motor 1 is controlled to maintain the rated voltage by the automatic voltage regulator 6, the field circuit 13
An excessive amount of turtle fi33 flows. This electric current is rated at 4~
It is said to reach five times as much.

Also, since the speed of the main engine decreases by 1, the generator motor l
The ratio between the terminal voltage and the speed increases, and the resulting voltage-frequency ratio 34 increases. Generally, generator motors are operated so that the ratio of voltage and frequency does not exceed the allowable value.
Exceeding 8 (fi) may cause damage to the generator motor and electrical/electrical equipment connected to it due to overexcitation.

[Purpose of power generation]

The present invention prevents electrical equipment such as the generator motor and the main transformer from being left in an overexcited state when input is lost while the generator motor is operating as a synchronous motor and the parallel circuit breaker becomes inoperable when it should be opened. The purpose of the present invention is to provide a control device that automatically prevents such occurrences and safely stops a generator motor.

[Summary of the invention]

For this reason, the present invention provides an input loss detection device that detects the loss of input while the generator motor is operating as a synchronous motor, and a voltage relay that detects the terminal voltage of the generator motor, so that when the input loss detection device operates, , the water turbine and the generator motor are controlled to an emergency stop, and if the voltage line is detected at a predetermined terminal voltage at this time, the r-toad of the exciter is controlled via the automatic voltage vI4 regulator of the generator motor. By interrupting the excitation current and cutting off the excitation current, an abnormal rise in the voltage-frequency ratio of the generator motor during the process of stopping the generator motor by emergency stop control is prevented, and the generator motor is stopped safely. It is characterized by

[Embodiments of the Invention] The present invention will be explained below with reference to embodiments shown in FIGS. 3, 4, and 5.

3rd M! '' according to an embodiment of the present invention
In the figure, the same reference numerals as in Fig. 1 indicate the same or corresponding parts, and 14 indicates the generator motor 1.
This is a voltage relay that detects the terminal voltage of

FIG. 4 is a control circuit diagram showing an example of operation control of the generator motor, and this control circuit consists of a contact 4 which is closed by the operation of an input loss detector 12 that detects the loss of input to the generator motor 1;
A closed relay 42 for main engine emergency stop operates when 1 is closed, and a time-limited relay 45 is energized by a series circuit of a contact 43 of the closed relay 42 and a contact 44 that is brought into contact by the operation of the voltage relay 14. A relay with a self-holding function that operates with a series circuit of the A contact 43 of the relay 42 and the contact 46 that is closed by the operation of the time-limited relay 45, and is reset by the B contact 47 of the blocking relay 42 (referred to as a key F IJ). )48
and one contact 49 of the blocking relay 42.
The emergency stop control is activated for the main engine, and the breath contact 50 of the key release 48 is configured to gate automatic voltage regulator #6 to effect an interruption.

FIG. 5 is a diagram showing a process of stopping the main engine according to the present invention.

Generally, when the generator wL motor is operated in conjunction with the power grid, the terminal voltage of the generator motor 1 is controlled by the automatic voltage regulator 6 so that it is always constant. Now, if an input loss occurs while the generator motor J is operating as a synchronous motor, the human power loss detector 12 detects this, its contacts 4 are closed, the emergency stop blocking relay 42 is activated, and the
Emergency stop control is activated for the main engine by the contact 43, and at the same time the water turbine is interrupted (not shown), the parallel circuit breaker 4 is opened. However, if the parallel circuit breaker 4 were to open due to some failure If the circuit is not opened and the circuit remains closed, the field breaker 9 cannot open the circuit. At this time, the main engine speeds Fi, , f1. However, the terminal voltage of generator motor 1 is automatic voltage! Since the iMi rectifier 6 is maintained at the regular winding rated value, the voltage relay 14 that detects the terminal voltage of the generator motor 1 remains in operation. When this state continues for a certain period of time, the operation of the first contact 43 of the closing relay 42 and the voltage relay 14 causes the time-limiting relay 45, which is excited by a series circuit with the closing contact 44, to operate, and the closing relay 42
The keep relay 48 operates in a series circuit between the & contact 43 and the contact 46 which is closed by the operation of the time-limited relay 45,
An r-t shutoff command is issued to the automatic voltage regulator 6 from the discontinuation point 50i, which is closed by the operation of the relay 48, and the r-) control of the excitation rectifier 8 is stopped. Rapidly dropping to zero? l! lI#. That is, since the terminal voltage of the generator motor 1 rapidly decreases, the voltage-frequency ratio also rapidly becomes zero3. By automatically performing such operation control, equipment such as the generator motor 1 and the main transformer 3 can be prevented from overloading. 111IJ function is to bring the main engine to a stable stop without Mm kc.

This process will be explained with reference to FIG. Although the speed 31 of the main engine rapidly decreases from the time point 30 when human power is lost due to loss of input, the terminal voltage 32 of the generator motor 1 is controlled by the automatic voltage regulator 6 to remain constant, so that the voltage of the generator motor 1 - The frequency ratio increases rapidly by 34, but the frequency ratio is 7-4.
From the point 35 when 8 operates, the automatic voltage regulator 6
-) t, an interruption occurs, and the field current 33 rapidly drops to zero, so the ti! ! It can be seen that the terminal voltage 32 and voltage-frequency ratio 34 of the c-motor 1 also quickly become zero.

In Figure 4, abnormality detection is explained using the contacts of the input loss detector.
The same function can be achieved with open contacts (not shown). Furthermore, the same function can be achieved by using a magnet circuit voltage or current detector (both not shown) in place of the generator motor terminal voltage detector.

〔Effect of the invention〕

As described above, according to the present invention, the source 1 [[motive is the same MIc
As a motive, when an input loss occurs during operation and an emergency stop operation is performed on the main engine, it is used in parallel, and if the interrupter fails and the main engine stops at 1', which cannot be opened, the voltage frequency ratio is kept below a certain value. Because of this control, it is possible to prevent damage to electrical equipment due to over-excitation, and it is possible to achieve the effect of preserving the life of the equipment.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a conventional system, Fig. 2 is a schematic diagram showing an overexcited dust phenomenon, Fig. 3 is a schematic diagram of a system showing a specific example of the present invention, and Fig. 4 is an implementation of the present invention. A control circuit diagram showing an example, FIG. 5 shows the field current of the main engine of the present invention. Here is a diagram showing the relationship between speed and pressure. l・Power generation wLIIJJ machine, 2...High pressure breaker, 3.
・Main transformer, 4 ・Parallel interrupter, 5, 10...
Instrument transformer, 6... Automatic voltage regulator, 7... Excitation transformer, 8... In rectifier, 9 Field interrupter, 1
1...11 five-flow device, 12...manpower loss detector,
13...Field circuit, 14...Voltage relay, :JI()
...Manpower loss point, 31...Rotational speed of generator motor,
32... Terminal voltage of the issuing vILwL#lJ machine, 33...
Field current, 34...Voltage-frequency ratio, 35 ・Time point,
41・A contact of input loss detector, 42...Closing relay for emergency stop, 43.49...Closing relay for emergency stop ll1
1 contact of a voltage relay, 44... 1 contact of a voltage relay, 45.
・・Time-limited relay, 46 Time-limited relay,] A contact contact 7
・B contact of emergency stop blocking relay, 48...Keep relay, 50...A contact of keep relay 0 Fig. 1 Fig. 3

Claims (1)

[Claims] In an operation control device for a generator motor that has an automatic voltage regulator and an excitation device and is operated in parallel with a grid, an input loss detection device and generator that detect loss of input while the generator motor is operating as a synchronous motor. A voltage relay that detects the terminal voltage of the motor is provided, and the generator motor is controlled to emergency stop on the condition that the input loss detection device operates, and the generator motor is automatically stopped on the condition that the input loss detection device and the voltage relay operate. This patented generator motor operation control device safely stops the generator motor by interrupting the r-)t of the excitation device via a voltage regulator.