JPS62142812A - Load control device for power generating plant - Google Patents

Abstract

PURPOSE:To facilitate adjustment, test and the like performed in the case of a power generating unit consisting of a plurality of power-generating plants by providing a means to issue or remove orders to perform maintenance for a plant respectively, and then controlling the output of generators so that it is switched to and from an actual generator output and a desired output accord ing to said orders. CONSTITUTION:On the outside of an overall load-control device 100 are provided switches A-J for appointing each of the plants No.1-No.10 to a maintenance mode respectively. The operating state of each switch is input into a load MW signal entering into an adder 108 for the output of each plant, and at the same time, it is input to switching devices 112-202 for each desired output arithmetic circuit. These switching devices are provided in such a manner that, for example, for the switch A, it is switched from a desired output signal 111a to a signal set in the load setting device 112a. In addition, when an arbitrary unit is selected as the maintenance mode, the load signal of the relevant plant entering into the adder 108 is mad to zero so that it can be neglected with respect to the overall load control.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a plurality of gas turbines, steam turbines, 9!, etc., such as a combined power generation unit. This invention relates to a load control device for a power generation plant consisting of a combination of electric machines, etc.

[Technical background of the invention and its problems]

In a configuration that consists of a combination of multiple gas turbines, steam turbines, generators, etc. (hereinafter referred to as a plant), such as a combined cycle power generation unit, the target output (also referred to as load) required for the power generation unit is the same as that of multiple power generation plants. This is achieved by the sum of the outputs. Therefore, in such a combined power generation plant, the target output is controlled by a general load control device (hereinafter referred to as GLC) that takes into account the number of plants in operation. A combined cycle power generation plant generally has a control system configured so that each power generation plant can be operated independently. FIG. 2 shows an example of the overall configuration of a control system for a combined cycle power generation unit, which is a specific example of a combined cycle power generation plant.

The operator is connected from the central control room to the unit central control panel 10.
The auxiliary monitoring panel 20 is used to operate and monitor the entire unit. Each combined cycle power generation plant has an air compressor 1. Combustor 2. Gas turbine 3. Exhaust heat recovery boiler (
(referred to as HRS G)4. It is composed of a steam turbine 5 and a generator 6.

The 1ti control system has a unit control computer 30. A transmission system 40 and a station (50 is Na l
The equipment is capable of automatic operation via a remote station (51 is for Na2) and a remote station (51 is for Nα1).

The operator sets the operation schedule for the n plants using the automation panel on the central 2 operation panel 10. The control computer 30 calculates an operation schedule that takes into account the operating status of the plant and the cumulative operating time of major equipment (gas turbines and steam turbines), and transmits each schedule to a remote station through the stations of each plant using the transmission system 40. tell. In the Na1 plant, the remote station 51 sends operation commands to each device from 52 to 57 using transmission signals or electrical signals, and the Na1
Perform operations necessary to start or stop the plant. The operator's commands as the target output for the entire power generation unit are given from the control computer, while the commands from the central supply are given to the general load controller (hereinafter referred to as GL) 100 through the communication device, where the individual targets for each plant are given. The output is divided into outputs and transmitted to the gas turbine control device 53 of each plant as a load command 101 using a signal cable separate from the transmission system 40.In the system configuration shown in FIG. The transmission system 40 that transmits plant monitoring data and the transmission line that transmits the load command 101 from the 0LC 100 to each gas turbine control device, which performs load increase/decrease operations for load operation after each plant startup is completed, are used for risk dispersion. Therefore, they are separated into separate transmission lines.

Figure 3 shows a block diagram of the current general load control device (GLC). The main signal given to GLCloo from the outside is the mid-supply command 300. In this case, the target load command 302 from the target load setter 102 is manually set by the AFC signal 30 based on the frequency fluctuation of the grid, and n power plants.

If n=10, the total output of 10 generators (MW)
The output signal from Nα1 to NαlO unit is sent to the adder 108 which calculates the gain of the multiplier 109.
This is the GLC AUTO mode word of each unit to the function generator 110, which is variable depending on the number of units.

On the other hand, the main signals output from the GLC 100 to the outside include the gas turbine control device (
115 for Nα1 to 205 for Nα10). Based on this control signal, each gas turbine control device adjusts the amount of gas fuel sent to the combustor 2 shown in Fig. 2 to increase or decrease the output of the gas turbine and the amount of steam generated, thereby adjusting the output of the heavy electrical equipment 61 to the target value. control to suit.

As shown in the schematic block diagram of FIG.
0, either the intermediate supply command 300 or the target load command 302 from the target load setting device 102 by the operating tool.

The deviation signal obtained from the actual output (total value of each unit) signal by the subtracter 107 is multiplied by a gain based on the number of units under GLC control by the multiplier 109, and then the proportional/integrator 1
At step 11, a target output signal 111a to each unit is calculated.

The target output signal to the Nα1 unit is set by the switch 112 to GL.
If the C side is selected, the upper and lower limits are 113 and N.
The output (
MW) is transmitted to the Nα1 gas turbine control device 1158 as an increase/decrease signal. When the AUT○ mode of the GLC is off, the switch 112 is switched to the load setter 112a side, and the signal given by the load setter instead of the target output signal 111a is switched to the gas turbine controller 115 by the deviation from the actual output. will be communicated to.

In this way, gas turbine control is performed for the units selected in GLC AUTO mode from Nα1 to N(110 units) so that the deviation between the actual output and target output signal of each unit is zero. A device increases the gas turbine fuel and controls the generator output to a predetermined value.

Each plant that makes up Unit 1- will be stopped for regular inspections,
To make adjustments after inspection, repeat operations such as turning on the generator output for a short time and then stopping it again, or to conduct simulation tests using simulated signals instead of actual output signals to confirm only the operation of the control circuit. As can be seen from the explanation using FIG. 3 above, this may cause disturbance to the load control of the entire unit or may cause an erroneous signal to be provided. In order to prevent this, it is necessary to forcibly reduce the external signal to zero for the object to be adjusted or tested, such as the Nα1 plant, or to remove the signal cable. However, performing such work while GLCloo is controlling other plants or the entire load may cause problems such as interfering with the control circuit, erroneously causing an abnormal signal input, or forgetting to restore the wiring. may occur.

A general load control device (GLC) that integrates the output (MW) of multiple power plants and performs load control as one unit.
In this case, it is necessary to adjust the load control individually during periodic inspections of each plant or due to malfunctions in the plant load control. Even in such a case, the unit as a whole must continue to operate under load according to the normal intermediate supply command).

[Purpose of the invention]

The purpose of the present invention is to make it possible to arbitrarily turn on and off the generator output, to repeat output increases and decreases in a short period of time, and to control the input signals necessary for controlling the generator output etc. in individual adjustments of each plant. An object of the present invention is to obtain a load control device for a power generation plant that does not interfere with the original integrated load control function of a GLC even when an adjustment test such as a simulation is performed.

[Embodiments of the invention]

FIG. 1 shows the configuration of the present invention. External to GLCloo, for example, on the control panel where operational instruments are installed.

Switches A to J corresponding to plants Nα1 to Nα10 are provided, and by operating these switches, each plant can be individually designated to maintenance mode. The operating state of this switch is determined by GLC, and the load (from NαIMW to NαIOM) entering the adder 108 of each plant output is
(up to W) is included in the signal as a condition.

In addition, the same state of switches A-J is input to the switch (112 to 202) of the target output calculation circuit of each plant, and depending on the operating state of the switch (maintenance mode is specified), the switch is set to the target output for switch A. The output signal 111a is switched to the signal set in the load setting device 112a.

The same applies to the other switches B to J.

By operating any of the switches A to J,
When you select any unit to maintenance mode, 0LC10
The load signal of the corresponding plant that enters the zero target load adder 108 is forcibly set to zero and is no longer taken into consideration in the overall load control. On the other hand, the target output signal of each plant is Nα1
In the case of a plant, the switching device 112 is switched to the signal from the load setting device 112a by the operation of switch A, and the signal from the load setting device 1
The target output can be arbitrarily set by manually operating 12a. In this case, the plant in which the maintenance mode is not selected is controlled to follow the target output 111a according to the signal from the load calculation circuit 100a.

With the configuration shown in Figure 3, for example, Nα1 kerant can be converted to GLC.
GL input to the function generator 110 when removed from the control state
Among the CAUTO mode signals, Nα1 is turned off (reset state), and the switch 112 is switched to the signal from the load setting device 112a. Since the function generator 110 loses output tracking for 1/10 unit, this is used as the AUT of the remaining GLCs.
○ Increase the gain of the multiplier 109 to 179 to compensate for the number of units. When the output of the Nα1 plant excluded by GLC control is made smaller by sequentially lowering the set value of the load setter 112a, this output decrease is fed back and the output signal of the subtracter 107 becomes positive with respect to the target load. Become. This positive deviation signal is multiplied by the gain in the multiplier 109, and the proportional
Target output signal 111a to each plant in integrator 111
Calculate so that Since the other nine units of the Nn 1 plant are all in the GLC AUTO state, the switch is on the automatic side, and the plants from Na 2 to Nol 0 increase the output by 179 of the previous positive deviation signal. An output increase signal is sent to the gas turbine control device in the direction of increasing the output.

In this way, this operation is performed until the total output of the nine plants increases and the previous deviation signal becomes zero, and the remaining nine plants recover by the amount that the output of the Nα1 plant has been reduced.

In this way, even if one plant is stopped, the GLC100 can control the overall output to match the target value as long as the remaining plants can compensate. However, I stopped and inspected it.

After that, in order to adjust and check the plant main body and control equipment, the plant is started up and the output is turned on and off to the power plant bus, or the Nα1 output signal is simulated to perform a mock test to check the operation of the control circuit. If you input a signal and increase or decrease the output within a short period of time, G
L C100 changes G according to the output feedback signal.
I frequently operate the LC AUTO plant. In order to maintain stable output, it is desirable to eliminate output fluctuations due to such adjustments and simulations. Therefore, the first
For GLCloo equipped with the circuit shown in the figure, any of the switches A to J can be operated to individually put the plant into maintenance mode so that the output of that plant is not fed back to the arithmetic circuit.

To return the plant to GLCloo's load control after maintenance, start the plant, release the maintenance mode, connect the generator output to the bus within the plant, and then set the load to an appropriate value using the load setting device 112a. Increase the output and G
All you have to do is shift to the LC AUT○ mode. At this time,
The output feedback of the Nα1 plant that was being maintained was also input to the adder 108 during the construction period, so if the output of Nα1 Plan 1~ was brought to a value close to 1/10 of the overall target output, it was possible to shift to GLCAUTO. Sometimes the output is almost equal to the target output given by 1lla,
A smooth recovery of the plant is possible.

The present invention is applicable not only to a plurality of combined cycle power generation plant systems as shown in the overall system configuration diagram of FIG. 2, but also to the case of centrally controlling a plurality of one ordinary thermal power generation plant. In the case of a normal thermal power plant, the compressor 1 in Figure 2. Combustor 2, gas turbine 3. There is no exhaust heat recovery boiler (HR8G) 4, and instead a boiler that is a steam generator is provided. The configuration of the GLC100 is basically the same as that shown in Figures 1 and 3, and the number of operating units in the plant that is centrally controlled by the GLC can be changed by specifying the number of operating units, the number of GLC AUTO units, and the maintenance mode. and GLC
A target output signal commensurate with the AUTO or maintenance mode status of the plant is sent to each plant. FIG. 4 shows a control system configuration diagram of a typical power generation plant. The target output signal 101 calculated as described above in the OL C100 is sent from the remote station (51 for Nut) to the steam turbine control device via each station 41 and 50, 60, 70 of the transmission system 40. The target output signal is different from that of a combined power generation plant, and 3. It is sent to a steam turbine control device 53 for a steam turbine, and controls the output of the generator 5 to match the target output by operating the regulating valve 4. The central control panel 10 is provided with an operation control panel 11 and a cathode ray tube display device 1112 (C, RT) for monitoring and operation.

Operators monitor and operate multiple power plants at once.

The panel 11 is provided with operation switches or pushbuttons for designating each of the plants mentioned above into maintenance mode, and a message is displayed on the CRT indicating the status of the designated result. Even if the outputs of the respective power plants are not the same in this configuration, the present invention can be similarly applied by calculating the target output in proportion to each output.

In the circuit shown in Fig. 1 above, the value obtained by dividing the target output by the number of operating plants at the time of canceling the maintenance mode is set as the target output of the plant, and the GLC automatically controls the output of the plant to that value. Uses GLC with added functions. When the plant is returned from the maintenance mode using GLG 100, it is not necessary to operate the load setter with one manual operation to bring the plant output close to the target output signal 111a. Without performing this operation, the operator can smoothly return the plant to the GLCAUT○ state.

A GLC configuration diagram including this function is shown in FIG.

In this embodiment, the calculation units 100c and 100d divide the target output signal of the entire unit by the number of operating units including the relevant plant to obtain the expected target output (■) per unit. When the corresponding plant is released from maintenance mode and status A is reset, contact B is turned on according to the logic shown in the figure, and the target output ■ is added to the adder 116, replacing the signal from the load setting device 112a. The Nα1 plant output can be brought closer to the output target value 111a, and the operator can now smoothly shift the plant to the GLC AUT◯ mode. When the GLC becomes AUT○, the switch 112 is switched to the signal 111a, the previous contact B is reset, and only the target output signal 111a is applied to 116. Other plants Nα2 to N
The functions up to n10 are the same as those described above.

〔Effect of the invention〕

By using the integrated load control device of the present invention.

When inspecting individual plants of multiple power generation plants for maintenance, testing using simulated generator output signals, or repeating increases and decreases in output in a short period of time for adjustment, the This allows operators to easily and safely specify maintenance mode and return to maintenance mode.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is an overall configuration diagram of a control system for a combined power generation plant,
FIG. 3 is a block diagram of a conventional example, FIG. 4 is an overall configuration diagram of a control system for a conventional power plant, and FIG. 5 is a block diagram showing another embodiment of the present invention. 100... Integrated load control device 100a... Load command calculation circuit 100b... Target load calculation circuit 102... Target load setter 112a... Load setting device agent Patent attorney Noriyuki Chika Yudo Hirofumi Mitsumata Figure 2

Claims (1)

[Claims] When a power generation unit is composed of multiple power generation plants, each with the same output or different outputs, the target output given to the entire unit is determined by considering the operating status and control status of each plant. In the load control device of a power generation plant that controls the output of the plant, there is a means for specifying or canceling maintenance for each plant individually, and based on the designation of this maintenance mode, the operating state of the relevant plant is controlled by the overall load control by other plants. A load control device for a power generation plant, comprising means for switching an actual generator output signal and a target output signal so as not to interfere with the generator output signal.