JPS6169398A - Excitation controller of synchronous generator - Google Patents

Abstract

PURPOSE:To obtain an excitation controller of synchronous generator without fluctuating a system when an automatic voltage regulator is defective by starting the control of an automatic following unit when the voltage of the generator arrives at 90-100% of the rated voltage. CONSTITUTION:When a contact 18a closed if a generator voltage arrives at 90-100%, a contact 21b opened if the manual operation of a voltage setter 70E is performed, a contact 14a closed by an AVR automatic selection, and a contact 15b opened when an automatic following unit AFU is defective are all closed, an auxiliary relay 12 for forming an AFU control state command is operated. The unit AFU controls to match the value of a voltage setter 70E of a constant-exciting regulator MEC to a voltage setter 90R of an automatic voltage regulator AVR. Thus, the abrupt variation in the generator voltage when the AVR is defective can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an excitation control device for a synchronous generator.

[Technical background of the invention and its problems]

Synchronous oscillation using thyristor excitation method = -[V4 excitation control devices include an automatic voltage regulator (hereinafter referred to as AVR) that controls the voltage of the conventional synchronous oscillation to a certain set value, and a There is a constant excitation regulator (hereinafter referred to as MEC) that is used in the event of a failure and controls the field voltage to a certain set value.

Ru.

Normal control is performed by AVRi2, but
In order to smoothly control the MEC (-) in the event of a failure, the AVH voltage setting device (hereinafter referred to as 9LIR) is
Control the voltage setting device (hereinafter referred to as 70E) to match the value! III] A tracking unit (hereinafter referred to as AFU) is used.

In conventional control, a signal of several seconds after the power generation breaker is turned on is used as the start condition for control based on the AFU. In order to turn on the generator breaker, it is necessary to control the generation peak pressure to match the system voltage, and this control is performed by changing the set value of 90R. During this control, the AFU has not started control, so the set value of 90R and the set value of 70E are often different.

FIG. 5 shows an example of a sequence diagram for generating an AFU control start command in a conventional control device C-.

A keep relay is used as the relay that generates the AFU control start command 12, and the contact 1 closes within a few seconds after the generator breaker is turned on.
3a, AFU when both contact 14a closes when AVR automatically selects and contact 15b opens when AF port fails, or when all are closed.
The keep relay 12 that generates a control start command operates.

Further, when the above-mentioned reverse contacts 13b, 14b, and 15a are opened, the keep relay 12 returns to its original state. When the keep relay 12 operates, AFU sub-control is started, and as shown on the right side of FIG. 2, the 7tJE increase/decrease command 16 or 7tJE decrease command 17 from AI'υ is used to increase/decrease 70E10.

Therefore, if an AVR malfunction occurs at this point and control is transferred from AVR to MECl2, the output voltage of the generator will change suddenly. Especially at the entrance A immediately after the generator breaker is turned on.
If switching from VR to MEC is performed, there is a possibility that large system fluctuations will occur.

[Purpose of the invention]

The object of the present invention is to prevent the system from being disturbed even if the automatic heavy pressure regulator fails within a few seconds after the generator is installed and the constant excitation regulator (-) switches to control C2 (-). The object of the present invention is to obtain an excitation control device for a synchronous generator.

[Summary of the invention]

In the present invention, the generator voltage is 9L to 100C of the rated voltage.
(-) A voltage relay that operates is provided, and automatic tracking is performed to match the setting value of the constant excitation regulator setting device with the setting value of the automatic voltage regulator setting device on the condition that this voltage relay is activated. It is characterized by starting control of the device.

[Funny example of invention]

FIG. 1 is an example of a configuration diagram of an excitation system of a synchronous generator using a thyristor excitation method. In the thyristor excitation method, the output of the synchronous blunt bale 1 is converted to the required voltage value (-) by the excitation transformer 2, then rectified by the thyristor bridge 3 and supplied to the field winding 5 via the field breaker 4. This excitation method uses its own output as the wJ magnetic source of the synchronous generator, so no other excitation source is required.Furthermore, the firing angle of the thyristor pritz 3 is determined by the output of the AVR6 or MEC7. Since the control is performed by changing the control, it has the characteristic of being quick to respond, so it has been used frequently in recent years.

AVR6in inputs the output voltage of the synchronous generator 1 via the instrument transformer 8, and inputs this output voltage and the setting device (90R).
Control the gate signal of Cyrisk so that the set values of 9 are equal. On the other hand, the MEC7+= is controlled so that the field voltage is input to the output voltage of the synchronous generator in the AVR6 so that this magnetizing magnetic pressure becomes equal to the set value of the setter (70E) 10.

AVR6, ME; C7, , /) outputs are each AFU
111 is input and the control start command 12a based on Aii'U 11 i= is on, the output of MEC7 becomes A.
70E from AFU 11 to be equal to the output of VR6
10t=Control is being performed to issue an increase/decrease command.

FIG. 2 shows three examples of how to install a voltage relay among the configuration diagrams according to the present invention.

The configuration is exactly the same as in Figure 1 except for the voltage relay. In the present invention, the generator voltage reaches 90% to 100% +=! l) A voltage relay is required to detect voltage in order to start controlling the AFU, but the voltage relay can be installed in tal, tb), tel, etc. in Figure 2, and any method is possible. (Al is an example in which the voltage relay 18 is connected to the secondary side of the instrument transformer 80, and (b) is an example in which an auxiliary transformer 19 for synchronous power supply is provided in parallel with the excitation transformer 2, and the secondary side of this auxiliary transformer 19 is An example in which the voltage relay 18 is connected, and (e) is an example in which the synchronous power supply auxiliary transformer 19 is connected to the secondary side of the excitation transformer 20, and the heavy voltage relay 18 is connected to the secondary side of this transformer 190.

Figure 3 shows an example of a sequence diagram of an AFU control start command according to the present invention. In the present invention, the generator voltage is 917% to 1
By reaching 00%, it is assumed that the activation of the excitation system has been completed, and AFU control is started.

This starts the p synchronization operation upon completion of the activation of the excitation system, and
This is because the set value of H begins to change. When the generator is stopped, it depends on the open condition of the conventional field breaker 91JR, 70B
The set values of 90R and 70H will be equal until the set value of 99OR is changed by synchronous operation because the set value of 90R and 70H are controlled to be punctured by 4 times so that the specified voltage is generated when there is no load. control by AFU is not required. Therefore, it is sufficient to start controlling the AFU from the time when the excitation system is finished starting and the synchronization operation is started.

In FIG. 3, the contacts 18a and 70E are closed when the generator voltage reaches 90% and 100%, respectively, and the contacts 21b and 1! are opened when the manual operation of 70E is performed. : AVt (When the contact 14a that closes when self-selected and the AFU fail (-) when the contact 15b that opens - is closed, the auxiliary relay 12 that generates the AFU control start command operates.

In FIG. 5, a keep relay is used as the relay 12, but in this example, an ordinary auxiliary relay is used.

The reason for this is to open the contact 21b only when the 70E is manually operated, thereby interrupting the 70hi control from the AFU. When the auxiliary relay 12 operates, AFU 1WII is activated at the contact 12a as shown in FIG.
Start the Jl control and connect contact 12 as shown on the right side of Figure 3.
An increase/decrease operation of 70E10 is performed by the 'IOE increase command 16 or decrease command 17 from the AFU via a.

Note that FIG. 4 shows a block diagram showing another embodiment of the excitation system start-up completion condition. In the thyristor excitation method, the excitation source is supplied by the voltage from the generator itself, but at the very first startup, the starter voltage is zero, so it is necessary to provide initial excitation voltage from another source. Control is performed to connect the station battery to the field circuit via the initial excitation contactor. This initial excitation contactor must be in an open state when the excitation system is activated. Therefore, it is also possible to generate the excitation system start-up completion signal 24 by combining the voltage 90 to 100 voltages 18a and the initial excitation contactor open signal 22 in FIG.

〔Effect of the invention〕

As shown above, the present invention can be used (-) to eliminate the possibility that conventional control would cause a sudden change in the power generation pressure in the event of an AVR failure, and the possibility of causing large fluctuations in the system, especially after a parallel failure, The reliability of the excitation control device can be improved as well.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of the excitation system of a synchronous generator using the Cyrisk excitation method, Figure 2 is
is a configuration diagram showing how to insert a voltage relay according to the present invention C2,
FIG. 3 is a sequence diagram of an AFU control start command according to the present invention, FIG. 4 is a block diagram showing another example of excitation system startup completion conditions, and FIG. 5 is a sequence diagram of an AFU control start command in a conventional control device. It is.

Claims (1)

[Claims] In the excitation control device for a synchronous generator using the thyristor excitation method, the generator voltage is 90% to 100% of the rated voltage.
a voltage relay that operates when the voltage reaches the set value, an automatic voltage regulator that controls the generator voltage to match the set value, a constant excitation regulator that controls the field voltage to match the set value, and an automatic voltage regulator and The voltage relay is equipped with a setting device that determines the setting value of the constant excitation regulator, and an automatic follow-up device that performs an operation to match the setting value of the constant excitation regulator with the setting value of the automatic voltage regulator setting device. 1. An excitation control device for a synchronous generator, characterized in that control of an automatic follow-up device is started on condition that the device is activated.