JPH114597A - Control device of stationary drive device in power generation facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the out-flow of harmonics to a power supply system, by allowing a plurality of stationary drive devices to receive power from each of different power supply systems. SOLUTION: The power of the power supplies of a plurality of stationary drive devices 5a and 5b is received from each different power supply systems 4a and 4b, the out-flow to the power supply system of the constituent of harmonics being generated from the stationary drive devices 5a and 5b is divided into power supply systems 4a and 4b, and the out-flow component of the harmonics per power supply system is reduced to 50%. More specifically, it may be estimated that the component of the harmonics that can be made to flow to one power supply system becomes two times larger than that of a conventional circuit configuration example, thus reducing the percentage impedance of transformers 2b and 2c for the stationary drive device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a stationary drive device in a power generation facility, which is applied to, for example, a thermal power plant and has a gas turbine and a generator connected to one shaft.

[0002]

2. Description of the Related Art Generally, a process in which a lockout relay is activated and stopped due to a generator accident from a state in which a gas turbine is normally operating is performed by opening an AC circuit breaker of the generator after the lockout relay is activated. It reaches the turbine trip.

[0003] At that time, the gas turbine suddenly reduces the fuel supply from the rated operation or the partial load operation to reach the no-load operation, and the generator is disconnected from the external power system. Therefore, thereafter, since the rotation speed of the gas turbine does not depend on the frequency of the external power system, the gas turbine is sufficiently throttled to reduce the fuel supply so as to reduce the rotation speed so that the gas turbine does not exceed the rated rotation speed. There is a need.

[0004] In this stopping process, the temperature of the combustor, the transition piece, the first stage stationary blade and the first stage moving blade, which become the high temperature portion of the gas turbine, rapidly decreases.
For example, in a gas turbine of the 1300 ° C. class, the inlet temperature of the first stage blade is 1300 ° C. at the time of base load, but it changes from about 700 ° C. to 900 ° C. during the no-load operation. 20 ℃ to 50 ℃ close to the temperature
It will drop to about ° C.

[0005] As a result, a high temperature portion of the gas turbine receives a large amount of thermal stress, and this thermal stress greatly reduces the life of the gas turbine. Therefore, by starting the stationary starter and operating the generator as an electric motor to control the rotation speed of the shaft, the change in the gas temperature at the gas turbine inlet or the change rate thereof is kept within a predetermined value so that the gas turbine is started. Extends the life of high-temperature components.

Here, the following factors are considered as causes for stopping the gas turbine. In other words, (1) a stop because power generation is no longer required due to the power generation plan;
(2) Failure of generator or gas turbine due to failure or trouble, (3) Despite the fact that generator and gas turbine are sound, equipment that connects the generator in the power plant and the transmission system in an electric circuit ( (E.g., transformers), accidental shutdown due to power failure from power generation equipment due to accident, (4) equipment failure in power transmission system despite generators and gas turbines being healthy, or There is an unexpected outage due to power transmission failure from the power generation equipment due to an accident such as a lightning strike.

[0007]

In the case of the stop factor of the above (1), since there is information on the stop of the power generation equipment in advance, it can be stopped by using the stationary drive device, but (2) In the case of the stop factors of (3) and (4), it is not possible to start the stationary drive device because it is not known when it occurs.

[0008] In the case of the above-mentioned stop factor (2), in the case of an accident inside the generator, it is not possible to supply a current from the stationary drive to operate the motor of the generator. No need to think about starting. Also, in the event of a gas turbine accident, the gas turbine is not stopped using the stationary drive unit, but is stopped in an emergency. Therefore, there is no need to consider starting the stationary drive unit.

In the case of the stop factors (3) and (4), since both the gas turbine and the generator are sound, the rotary shaft can be stopped by a stop method using a stationary drive device. Nevertheless, it does not incorporate such an interlock.

Generally, a generator and electric equipment are provided with a protective relay for protecting the equipment, and a breaker suitable for interrupting the flow of electricity by the operation of the protective relay is provided. Although the system is configured to open, there is no interlock configured to activate the static activation device during an emergency stop.

FIG. 7 is a circuit diagram showing the configuration of a conventional thermal power plant. As shown in FIG. 7, the generator 1 is connected to a power supply system 4 via a main transformer 2a and an AC circuit breaker (52G) 3a. In addition, the stationary drive device 5
a, 5b are transformers 2b, 2 for a stationary drive device, respectively.
c and the AC circuit breakers 3b, 3c.

As described above, the plurality of stationary driving devices 5a, 5
b in the same power generation facility, their power is supplied from the same power supply system 4.
Outflow of harmonics to the

As means for suppressing such harmonics, a transformer for a stationary drive device having a larger percentage impedance than usual is required. That is, it is necessary to design the percent impedance of the transformers 2b and 2c for the stationary drive device to be higher than the standard value.

On the other hand, as a factor at the time of an emergency stop due to a generator accident, as shown in FIG. 8, a system accident and a generator external accident (main circuit accident in a power plant excluding external system accident and generator internal accident cause) are shown. ) And a generator internal accident (generator, excitation device, stationary drive device accident), and these are ORed together in the OR circuit 6 to activate the generator accident lockout relay. AC generator circuit breaker (52
G) Open 3a, leading to gas turbine trip.

In the case of a generator external accident and a generator internal accident, a logical sum is obtained by the OR circuit 7, and the DC circuit breaker (41E) provided on the field side of the generator 1 is opened.

Therefore, the system accident, the generator external accident, and the generator internal accident are collectively operated to activate the generator accident lockout relay, and the generator AC circuit breaker (52G)
3a is open, the generator 1 is healthy, but the stationary drive is not operated, so that when the lockout relay is activated, the rotational speed of the shaft is rapidly reduced,
As a result, the life of the gas turbine is reduced.

The present invention has been made in consideration of the above circumstances, and has as its object to provide a control device for a stationary drive device in a power generation facility that reduces outflow of harmonics to a power supply system.

Another object of the present invention is as follows.
An object of the present invention is to provide a control device for a stationary drive device in a power generation facility that has a long life and a high reliability in a gas turbine high-temperature component during a gas turbine shutdown process.

[0019]

In order to solve the above-mentioned problems, a first aspect of the present invention is to provide at least one rotating shaft integrally connecting a gas turbine and a generator, and to provide a current to the generator. In the control device of the stationary drive device in the power generation equipment in which a plurality of stationary drive devices for supplying the electric motor to operate the generator are provided, the plurality of stationary drive devices each receive power from different power supply systems. Features.

According to a second aspect of the present invention, there is provided at least one rotating shaft integrally connecting the gas turbine and the generator, and a stationary drive device for supplying a current to the generator and operating the generator as a motor. In the control device of the stationary drive device in the power generation facility, a startability determination unit that determines whether the static drive device can be activated at the time of an emergency stop is provided, and when the startup is possible, the static drive device is activated. I do.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a circuit diagram showing a first embodiment of a control device for a stationary drive device in a power generation facility according to the present invention. Note that the same or corresponding parts as those in the conventional configuration will be described using the same reference numerals as those in FIG. In the first embodiment, an example in which the present invention is applied to a thermal power generation facility is shown.
The equipment has two stationary drive units for each unit.

As shown in FIG. 1, the rotating shafts of the gas turbine 10, the compressor 11 and the generator 1 are connected in a single shaft, and the generator 1 is driven to rotate by the driving force of the gas turbine 10 to generate electric power. Let it.

The generator 1 is connected to a power supply system 4a via a main transformer 2a and an AC circuit breaker 3a.
The stationary power supply 5a is connected to the same power supply system 4a via an AC circuit breaker 3b and a static drive device transformer 2b, and the AC power supply 3b and the static drive device transformer 2b are connected from the power supply system 4a. Power is supplied to the stationary drive device 5a via the power supply.

On the other hand, the power supply system 4a which is different from the power supply system 4a
b, a stationary drive device 5b is connected via an AC circuit breaker 3c and a static drive device transformer 2c, and is stationary from the power supply system 4b via the AC circuit breaker 3c and the static drive device transformer 2c. Power is supplied to the shape drive device 5b.

Next, the operation of the present embodiment will be described.

In the present embodiment, a plurality of stationary starting devices 5
a, 5b are supplied to separate power supply systems 4a, 4b, respectively.
, The outflow of the harmonic components generated from the stationary drive devices 5a and 5b to the power supply system can be divided into the two power supply systems 4a and 4b. As a result, the outflow component of harmonics per power system is reduced by 50%.
It becomes possible to reduce to.

That is, in the present embodiment, the outflow component of the harmonic per one power supply system can be reduced to 50%. In other words, the harmonic component which can flow out per one power supply system can be reduced. Is twice as large as that of the conventional circuit configuration example.

Therefore, the transformer 2 for the stationary drive device can be provided by expecting many harmonics that can flow out to the power supply system.
It is possible to reduce the percent impedance of b and 2c. Thus, the transformer 2 for the stationary drive device
It is possible to adopt the standard designs of b and 2c.

FIG. 2 is a circuit diagram showing a modification of the first embodiment of the control device of the stationary drive device in the power generation equipment according to the present invention. The same parts as those in the first embodiment will be described with the same reference numerals. This modification is based on the first
As in the embodiment, the facility has two stationary drive units for one generator.

As shown in FIG. 2, in the control device of the stationary drive device, the generator 1 includes a main transformer 2a and an AC circuit breaker 3a.
And a circuit that supplies power to the stationary drive device 5a from the space between the main transformer 2a and the generator 1 via the stationary drive device transformer 2b. Is a static drive device 5 from a separate power supply system 4b via an AC circuit breaker 3c and a static drive device transformer 2c.
b for supplying power to the power supply.

According to this modification, the stationary driving device 5
The outflow of the harmonic components generated from a and 5b to the power supply system can be divided into the two power supply systems 4a and 4b, and the same effect as in the first embodiment can be obtained.

In the first embodiment and the modified example, the case of the uniaxial type has been described. However, the same effect can be obtained in the case of the multiaxial type. In addition, the first
In the embodiment and the modified example, the case of the simple cycle in which the rotation axes of the gas turbine 10 and the generator 1 are connected to one axis has been described. The same effect can be obtained in the case of a combined cycle.

FIG. 3 is a circuit diagram showing a second embodiment of the control device of the stationary drive device in the power generation equipment according to the present invention. The same or corresponding parts as those in the first embodiment will be described with the same reference numerals. Although the gas turbine 10 and the compressor 11 are omitted in FIG. 3, the configuration in which the rotating shafts of the generator 1 and the gas turbine 10 and the compressor 11 are connected to one shaft is the same as that of the first embodiment. It is.

In this embodiment, the power supply for the stationary drive unit 5 is supplied from a system different from the rotating shaft of the power generation equipment. As shown in FIG. 3, the generator 1 is connected to a power supply system 4b via a main transformer 2a and an AC circuit breaker 3a, and is connected to a stationary drive device 5 via a disconnector (or circuit breaker) 12. The stationary drive device 5 is connected to another power supply system 4a via an AC circuit breaker 3b.

In this embodiment, a generator internal accident protection device 13 is provided to determine a generator internal accident, and the protection device 13 includes the generator 1 and the main transformer 2a.
Current information from the instrument current transformer 14a and voltage information from the instrument transformer 15a provided on the connection line for connecting the static drive device 5 at the time of emergency stop. It is input to a start command device 16 as a start permission / non-permission judgment means for judging whether or not the start is possible.

Similarly, a generator external accident protection device 17 for determining an accident outside the generator and other than the power transmission system (hereinafter referred to as a generator external accident) is provided. The current information is input from the current transformer 14b and the voltage information is input from the transformer 15a, and the operation signal is input to the start command device 16 of the stationary drive device 5.

Further, regarding the system protection device 18 for judging an accident in the power transmission system, current information and voltage information of the current transformer 14c and the transformer 15b of the instrument are input, and
The operation signal is input to the start command device 16 of the stationary drive device 5. In FIG. 3, reference numeral 19 denotes a DC breaker (generator field breaker) provided on the field side of the generator 1.

The gas turbine 10 is stopped in response to these protection device operation commands. The start command device 16 serving as a start permission / prohibition judging unit judges whether the stationary drive device 5 can be started using logic as shown in FIG. .

That is, in FIG. 3, since a circuit breaker or disconnector for dividing an electric circuit is not provided between the generator 1 and the main transformer 2a, in the case of an external accident of the generator, the stationary drive unit is provided. 5, the generator 1 cannot be operated by the electric motor, and the stationary drive device 5 can be used only at the time of a system failure, that is, when the system protection device 18 operates.

In this case, the operation signal of the system protection device 18 and the confirmation that the DC circuit breaker 19 is closed are instructed to open the AC circuit breaker 3a. 3b and a command to close the disconnector (or circuit breaker) 12, and after confirming the close, start the stationary drive device 5,
The generator 1 is driven by a motor.

That is, in the case of a generator external accident and a generator internal accident, a logical sum is obtained by the OR circuit 7, and the DC circuit breaker (41E) 19 provided on the field side of the generator 1 is opened. At the same time, when these accidents and a system accident occur, the OR circuit 6 performs a logical OR operation, opens the AC circuit breaker 3a of the generator 1, and leads to a gas turbine trip.

When the AC circuit breaker 3a is opened and a system fault occurs, a logical product is obtained by the AND circuit 20 and the start of the stationary drive device 5 is commanded. Next, when the start command of the stationary drive device 5 and the DC breaker 19 are closed, a logical product is obtained by the AND circuit 21 to instruct the AC breaker 3b and the disconnector (or breaker) 12 to be closed. Then, after confirming the closing, the stationary drive device 5 is started.

As described above, according to the present embodiment, the start command device 16 determines whether or not the stationary drive device 5 can be activated, so that the static drive device 5 is activated except in the case of a generator internal accident. By suppressing the rapid decrease in the rotation speed and controlling the rotation speed required on the gas turbine 10 side, the thermal stress of the high-temperature components of the gas turbine 10 can be reduced, and the life of the high-temperature components can be extended. It becomes possible.

FIG. 5 is a circuit diagram showing a modification of the second embodiment of the control device of the stationary drive device in the power generation equipment according to the present invention.

In this modification, as shown in FIG. 5, a circuit breaker (or disconnector) 12a for dividing an electric circuit is provided between the generator 1 and the main transformer 2a. in this case,
Judgment of a generator internal accident and a generator external accident, and a circuit breaker (or disconnector) only in the case of a generator internal accident
By opening 12, a stopping method using the stationary drive device 5 can be performed in the case of a generator external accident or a system accident.

The configuration of the protection device and the like is the same as that of the second embodiment.
6 may be changed as shown in the block diagram of FIG.

That is, in the case of a system fault and a generator external fault as shown in FIG. 6, a logical sum is obtained by the OR circuits 22 and 23, the AC circuit breaker 3a of the generator 1 is opened, and the gas turbine trips. .

In the case of an accident inside the generator, the AC circuit breaker 3a of the generator 1 is opened directly, and the DC circuit breaker 19 provided on the field side of the generator 1 is opened.

Reference numeral 24 denotes a knot circuit. When the AC circuit breaker 3a is opened and a system fault or a generator external fault occurs, a logical product is obtained by an AND circuit 20.
A command to start the stationary drive device 5 is issued. When the start command of the stationary drive device 5 and the DC breaker 19 are closed, a logical product is obtained by the AND circuit 21 and the AC breaker 3b is obtained.
And commanding the closing of the disconnector (or circuit breaker) 12, confirming the closing, and then activating the stationary drive device 5, and
Is driven by an electric motor.

As described above, according to the modified example, the stationary drive device 5 can be started except in the case of an accident inside the generator, so that the heat of the high-temperature parts of the gas turbine 10 can be increased similarly to the second embodiment. The stress can be reduced, and the service life of a high-temperature component can be extended.

In the second embodiment and the modification, the case of the uniaxial type has been described. However, the same effect can be obtained in the case of the multiaxial type. In addition, the second
In the embodiment and the modified example, the case of the simple cycle in which the rotation axes of the gas turbine 10 and the generator 1 are connected to one axis has been described. The same effect can be obtained in the case of a combined cycle.

Further, in each of the above embodiments, the case where the present invention is applied to a thermal power plant has been described. However, the present invention can also be applied to a nuclear power plant.

[0054]

As described above, according to the first aspect of the present invention,
According to this configuration, the plurality of stationary driving devices receive power from different power supply systems, respectively, so that the inflow of harmonics into the power supply system can be reduced as compared with the case where the same power supply system takes the same. As a result, the percent impedance of the static drive device transformer can be reduced, and the standard design of the static drive device transformer can be adopted.

According to a second aspect of the present invention, there is provided a start-up / non-start-up determination means for determining whether the start-up of the stationary drive unit is possible at the time of emergency stop,
When the start-up is possible, the static drive unit is started up, and the range and rate of change of the gas temperature in the high-temperature part of the gas turbine are kept low, so that the life of the high-temperature parts of the gas turbine can be extended. And the reliability can be improved.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a first embodiment of a control device for a stationary drive device in a power generation facility according to the present invention.

FIG. 2 is a circuit diagram showing a modification of the first embodiment of the control device of the stationary drive device in the power generation equipment according to the present invention.

FIG. 3 is a circuit diagram showing a second embodiment of the control device of the stationary drive device in the power generation equipment according to the present invention.

FIG. 4 is a diagram illustrating operation logic of a protection device according to a second embodiment.

FIG. 5 is a circuit diagram showing a modification of the second embodiment of the control device of the stationary drive device in the power generation equipment according to the present invention.

FIG. 6 is a diagram illustrating an operation logic of a protection device according to a modification of the second embodiment.

FIG. 7 is a circuit diagram showing a configuration of a conventional thermal power generation facility.

FIG. 8 is a diagram showing operation logic for a circuit diagram of a conventional thermal power generation facility.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Generator 2a Main transformer 2b, 2c Transformer for static drive 3a, 3b, 3c AC circuit breaker 4, 4a, 4b Power supply system 5, 5a, 5b Static drive 6 OR circuit 7 OR circuit 10 Gas turbine DESCRIPTION OF SYMBOLS 11 Compressor 12, 12a Disconnector (or circuit breaker) 13 Generator internal accident protection device 14a, 14b Instrument current transformer 15a, 15b Instrument transformer 16 Start command device (startability judgment means) 17 Generator external accident Protection device 18 System protection device 19 DC circuit breaker 20,21 AND circuit 22,23 OR circuit 24 Knot circuit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshiaki Miyasaka 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Corporation Head Office

Claims (2)

[Claims] 1. A power generation facility provided with at least one rotating shaft integrally connecting a gas turbine and a generator, and a plurality of stationary drive units installed to supply electric power to the generator and operate the generator as a motor. The control device for a stationary drive device in a power generation facility, wherein the plurality of stationary drive devices receive power from different power supply systems. 2. A power generation system having at least one rotating shaft in which a gas turbine and a generator are connected to one shaft, and a stationary drive device for supplying electric power to the generator and operating the generator as a motor. In the control device of the stationary drive device, a start-up / non-startup determination unit that determines whether the static drive unit can be activated at the time of an emergency stop is provided, and when the result of the determination can be activated, the static drive unit is activated. A control device for a stationary drive device in a power generation facility.