JP2002318615A - Remote monitor control system for plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To execute a safe and accurate unmanned operation when any abnormality is generated in an operation command inputted to an unmanned operating plant to be remotely monitor controlled. SOLUTION: A second communication line different from a first communication line is arranged between an in-plant controller 300 and a monitor control center 400, and the in-plant controller is provided with an operation command evaluating means 310 for evaluating the validity of an operation command signal 12 received through the first communication line and a signal transmitting/receiving means 210 for transmitting an operation command confirmation signal 16 for confirming the validity of the operation command signal through the second communication line, and for receiving an answer signal 17 of an operator 410 in the monitor control center to the operation command confirmation signal. The monitor control center is provided with a signal transmitting/receiving means 230 for receiving the operation command confirmation signal through the second communication line, and for transmitting an answer signal to the operation command confirmation signal. Then, the plant is controlled by an in-plant manipulated variable arithmetic means 330 based on the answer signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for transmitting an operation command signal from a supervisory control device in a supervisory control center to a plant at a remote location, and a control device installed in the plant receiving the operation command signal. The present invention relates to a plant remote monitoring control system that operates a plant based on a command signal.

[0002]

2. Description of the Related Art With the labor saving of plant operation, techniques for reducing the number of operators and for unmanned operation have been developed. One way to do this is to remotely monitor and control the plant. In such a plant remote monitoring and control system, securing safety is an important issue. Conventionally, communication lines and control computers are multiplexed, and when a normally used communication line or computer breaks down, another line or computer is used. For example, Japanese Patent Application Laid-Open No. 2000-59870 describes a method for providing a stable operation for such a remote monitoring control system.

[0003]

The above prior art is a technique for dealing with a case where a failure in a communication line or a computer becomes apparent. However, even if the function of the computer and the function of the communication line are normal, there is a possibility that the control signal may be illegally manipulated from the outside. In this case, if an operator is present at the plant, it is possible to judge the validity of the control signal or to inquire of the monitoring center monitoring staff based on the operator's experience. In the case of unmanned operation, the validity of the control signal must be determined by an algorithm programmed in advance in a computer, and an appropriate determination cannot be made in some cases.

[0004] It is an object of the present invention to provide a plant remote monitoring and control system which can appropriately process an abnormal operation command input to an unmanned plant which is remotely monitored and controlled.

[0005]

In order to solve the above problems, a second communication line different from the first communication line is provided between a control device and a monitoring control center in a plant, and a control in the plant is provided. A driving command evaluation unit that evaluates the validity of the driving command signal received via the first communication line;
Signal transmission / reception means for transmitting an operation command confirmation signal for confirming the validity of the operation command signal via the second communication line, and receiving an answer signal of an operator in the monitoring and control center to the operation command confirmation signal; The monitoring control center includes a signal transmitting / receiving means for receiving an operation command confirmation signal via the second communication line and transmitting a response signal to the operation command confirmation signal, and a control device in the plant based on the response signal. To control the plant.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. The embodiment of the present invention describes an example applied to remote monitoring control of a thermal power plant. FIG. 2 shows a basic configuration of a thermal power plant to be used. The thermal power plant includes a power generation facility 100 and an operation control device 300 thereof. Power generation equipment 100
Is described below. In the boiler 150, fuel and air are supplied to the burner 160 and burned, and the water supply pump 1
The feed water circulated by 40 is evaporated in the heat exchanger 152 provided in the furnace. Further, the steam that has been heated in the heat exchanger 153 and the superheater 154 at the subsequent stage and has become overheated rotates the high-pressure turbine 130 via the turbine control valve 121. The steam that has passed through the high-pressure turbine 130 is supplied to a reheater 156.
Then, the temperature is raised again and enters the low-pressure turbine 120. Electric power is generated using the generator 110 by the rotation of the high-pressure turbine 130 and the low-pressure turbine 120. Hereinafter, the steam at the inlet of the high-pressure turbine 130 is referred to as main steam, and the steam at the inlet of the low-pressure turbine 120 is referred to as reheat steam. In addition to the above components, the steam after driving the turbine is supplied to the power generation facility 100 with the cooling water 12.
There are also devices such as a condenser 125 for cooling by 6 and an exhaust gas treatment device 170 for removing harmful substances in the combustion gas. The gas passing through the exhaust gas treatment device 170 is a chimney 175
Emitted from the atmosphere. The operation state of the power generation equipment 100
Measured by data measuring devices such as generator output measuring device 111, main steam temperature (superheater outlet steam temperature) measuring device 122, main steam pressure measuring device 123, reheating steam temperature measuring device 124, reheating steam pressure measuring device 128, and the like. And transmitted to the operation control device 300. In addition to the above, the power generation equipment 100 is provided with devices for measuring various process amounts required for controlling the turbine rotation speed and the like, and the operation control device 300 also captures the measured values from these devices. . Here, the detailed description thereof is omitted. The operation control device 300 grasps the operation state of the power generation equipment 100 based on the process data, and controls the fuel flow control valve 162, the air flow control valve 161, the turbine control valve 12
1. The equipment such as the water supply pump 140 is operated. Here, the desirable state is basically such that the difference between the power generation command value from the central power plant and the power generation output value of the plant is as small as possible, and the difference between the rated speed of the turbine and the turbine speed is as small as possible. Driving in a small state.
The central power station (not shown) satisfies the total amount of power required in consideration of the amount of power (power generation) that can be supplied by each power plant and the power generation efficiency of each power plant, and has the highest fuel consumption (fuel consumption). The power generation amount (this is called a power generation amount command) for each generator is determined so that the cost is reduced.

Next, a control method based on the power generation amount command is shown in FIG. An operating frequency correction command (referred to as AFC) 502 is sent from the central power supply station in addition to the power generation command 501. The power generation amount command 501 and the AFC 502 are added to form a target load command signal 506. Target load command signal 50
6 passes the system frequency 503 after passing through the rate-of-change limiter 521.
And a frequency bias signal 516 generated based on a difference 515 between the MWD signal 507 and the specified frequency 504.
Becomes A signal obtained by adding the power generation amount correction signal 517 generated based on the difference 515 between the system frequency 503 and the specified frequency 504 to the MWD signal 507 is a turbine power generation amount command signal 50.
It becomes 8. The difference between the turbine power generation command signal 508 and the actual output 510 of the generator is the turbine output command 509. Also, the target value 519 of the boiler pressure and the actual pressure 51
The correction signal 522 generated based on the deviation from
The signal added to the signal 507 is converted into a boiler input command 520 (BI
Called D. ). The fuel flow rate, feed water flow rate, and air flow rate supplied to the boiler are determined based on the BID signal 520. On the other hand, in order to maintain the system frequency, control is performed by the following method. If the specified frequency 504 of 50H _Z is rated rotational speed of the turbine is 3000 rpm. A signal obtained by adding the difference 513 between the actual turbine speed 512 and the rated turbine speed 514 to the turbine output command 509 is defined as a turbine control valve opening command 511. The amount of steam required for the turbine is changed by the turbine control valve opening command 511 to control the rotation speed of the turbine. As described above, the thermal power plant receives the power generation command 501 and the operating frequency correction command 502, and is operated based on the commands. The control method shown in FIG. 5 is realized by the operation control device 300 of the plant.

Conventionally, the operation control device 300 normally has the ability to automatically operate without operator intervention.
When an abnormal condition occurs in the plant, the operation may be switched to manual operation at the discretion of the operator. Further, the power generation command 501 and the operating frequency correction command 502, which serve as guidelines for automatic plant operation, have conventionally been received from a remote central power supply station via a communication line. In the event of an abnormality, the operator could switch to manual operation at the discretion of the operator, or the operator could respond by inquiring the central power station of the command value over the telephone. However, when the operator is absent, the above-described operation by the operator becomes impossible. The present invention provides a system capable of coping with an abnormality of an operation command signal such as a power generation command 501 and an operation frequency correction command 502 even when the plant is operated unattended. There are various possible causes for the malfunction of the operation command signal, such as a physical failure of the transmission / reception device or communication line, a malfunction of the computer that calculates the command value, or an unauthorized manipulation of the signal from outside. There is.

FIG. 1 shows a remote monitoring control system for a plant according to a first embodiment of the present invention. In FIG.
The thermal power plant 1 and the centralized monitoring control center 400 can exchange information by communication. Centralized monitoring and control center 4
Reference numeral 00 designates the above-described central power supply station having remote monitoring and control functions of the plant. Although only one plant is shown in FIG. 1 as an example, the central monitoring and control center 400 may monitor and control a plurality of plants. As described above, the plant 1 basically includes the power generation facility 100 and the operation control device 300. Centralized monitoring and control center 400
Is basically composed of a monitoring control device 430 and an input / output device 420 serving as a man-machine interface. The monitoring and control device 430 transmits the operation information 11 such as the power generation amount of the plant transmitted from the plant 1 and other measured values.
Is received via the normal signal transmitting / receiving means 240 and displayed on the display screen of the input / output device 420. The operator 410 of the central monitoring control center 400 monitors the state of the plant. The operation command calculation means 440 calculates an operation command value such as a power generation amount command, and transmits the result 12 to the plant 1 via the normal signal transmission / reception means 240. The method of determining the power generation amount command includes, for example, the following method. Output Li and fuel consumption Fi of the generator with generator number i
Is approximated by a quadratic equation as shown in the following equation. Fi = ai × Li ² + bi × Li + ci (1) Here, ai, bi, and ci are coefficients representing the characteristics of the generator with the generator number i. Assuming that the power demand (load) is P and the loss due to power transmission and the like is P ′, then ΔLi = P + P ′ (2) Therefore, the generator output Li is obtained by using the Lagrange's undetermined multiplier method so as to satisfy the condition of the expression (2) and minimize the total fuel consumption of the expression (1). That is, in J = ΣFi-λ (ΣLi-P-P ′) (3), Li is determined so as to satisfy ∂J / ∂Li = 0 (4) ∂J / ∂λ = 0 (5). . This is a power generation amount command for each generator. However, the present invention is not limited to the above-described method of determining the power generation amount command, and other methods may be used. Therefore, the description of the method of determining the AFC is omitted.

[0010] The plant 1 transmits the operation information 11 and receives the operation command 120 via the normal signal transmission / reception means 220 of the operation control device 300. Run command 12 received
Is input to the validity evaluation unit 310 to evaluate the validity of the command value. In the evaluation method, as shown in FIG. 6, evaluation is performed according to the following procedure, and if any of the conditions is not satisfied, it is evaluated as abnormal. (1) Whether the command value is within the range between the upper limit and the lower limit. (2) Whether the temporal change rate of the signal is within the range between the upper limit and the lower limit. (3) The relationship between the system frequency and the AFC is Appropriate? AFC is in a direction to correct the deviation between the system frequency and the specified frequency. (4) Is the relationship between the system frequency and the power generation command appropriate? The deviation between the system frequency and the specified frequency tends to increase with time, and If the power generation command is in a direction to increase the deviation, it is evaluated as abnormal. The above (4) utilizes the fact that the system frequency decreases when the total power generation amount of each power plant is smaller than the power demand amount, and conversely, the system frequency increases when the total power generation amount is too large. is there. The evaluation method is not limited to the above method, and may be evaluated by another method. By the above processing, the operation command 12 is evaluated by the validity evaluation unit 310, and the evaluation result 13 is converted into the operation amount calculation unit 33.
Send to 0. When the evaluation result 13 is normal, the operation amount calculating means 330 calculates the operation amount 10 such as the fuel flow rate, the feed water flow rate, and the degree of opening and closing of the turbine valve by the control method shown in FIG. Thereby, the power generation facility 100 is controlled. If the evaluation result 13 is abnormal, the operation amount calculating means 3
30 sends a confirmation request signal 14 to the operation command confirmation means 320. The signal 14 includes the evaluation result 13 of the validity evaluation means 310. When the signal 14 is input, the operation command confirmation unit 320 transmits a confirmation signal 16 for inquiring whether the received operation command 12 is really abnormal. The confirmation signal 16 is transmitted to the centralized monitoring control center 400 by using another confirmation signal transmission / reception means 210 different from the normal signal transmission / reception means 220. Normal signal transmitting / receiving means 220
Is a dedicated communication line using an intranet, but the confirmation signal transmitting / receiving means 210 is a normal telephone line.

In the centralized monitoring control center 400, the confirmation signal transmitting / receiving means 230 receives the confirmation signal 16. The confirmation signal transmitting / receiving means 230 is a telephone, and the operator 410 in the centralized monitoring and control center 400 directly answers the telephone as in a normal telephone call. The confirmation signal 16 is an audio signal registered in advance and transmitted through a telephone line. The contents of the information conveyed by voice are the items judged as abnormal by the validity evaluation means 310 ((1) to (4) above), the received operation command 12 and the current value of the generator output. And the current value of the generator output reports the latest value every 5 seconds. The operator 410 of the centralized monitoring control center 400 listens to the information, and uses the input / output device 420 to operate the plant 1, the operation command 12 to the plant 1, the system frequency value, the total power generation amount, the operation status of other plants, and the like. To check whether the operation command reported by the confirmation signal 16 (voice) is correct. The check result of the operator 410 is transmitted to the plant 1 by operating the push button of the confirmation signal transmitting / receiving means 230 (telephone). The button operation is determined in advance as follows. (1) "♯" → "*": Switch to input mode (2) "1" → "*": Switch to information reception mode (3) "0" → "0" → "♯": Operation command is correct (4) “9” → “9” → “9” → “♯”: Operation command is incorrect. (5) “1” → “1”: Confirmation. (6) “3” → “3”: Cancel. When the operations of 3) and (4) are performed, a confirmation message flows. If the operation is OK, the operation of (5) is performed. If the operation is canceled, the operation of (6) is performed. In the case of (4), a correct operation command is input. The method is as follows. (7) “1” → “♯” → “♯”: Current status operation (8) “2” → “♯” → “♯”: Generator output designation (9) “3” → “♯” → “♯” ": Plant stop In the case of the above (8), the generator output specified after the operation of (8) is input in kW units. For example, in the case of 12345 kW, “1” → “2” → “3” → “4” → “5” → “♯” is input. For each operation, a confirmation message flows, and confirmation or cancellation processing is performed by the operations (5) and (6). The answer signal 17 input as described above is input to the operation command confirming means 320 via the telephone line. The above input method is an example, and another rule may be determined and operated. Instead of operating the push button, a voice confirmation system may be introduced to identify the voice of the operator. Operation command confirmation means 32
A value of 0 sends the answer signal 17 to the manipulated variable calculator 330. The operation amount calculation means 330 operates to determine the operation amount according to the answer signal 17 when the evaluation result 13 is “abnormal”.

According to the first embodiment, an incorrect operation command 12 is input to the unmanned plant 1 due to an abnormality in a normal communication line, communication means, monitoring and control device or an illegal signal operation from the outside. Even so, there is no need to worry about continuing wrong driving. In addition, by directly communicating with the operator 410 by completely different communication means from the normal communication means for confirmation between the operation control device 300 and the centralized monitoring and control device 430 of the plant 1, the judgment of the person (operator) can be made. Plant 1
Reliability due to unattended operation of the vehicle. In addition, since a telephone line and a telephone are used as communication means completely different from ordinary communication means, and remote monitoring and control can be performed by direct dialogue with voice, operation errors of the plant 1 are reduced.

FIG. 3 shows a second embodiment of the present invention.
The difference from the first embodiment in FIG. 1 is that communication signals 20 and 21 can be transmitted and received between the plant 1 and the plant 1b. For example, when the validity evaluation unit 310 determines that the operation command of the plant 1 is “abnormal”, the operation command confirmation unit 320 confirms the operation command via the confirmation signal transmission / reception unit 210 as shown in the first embodiment of FIG. The signal 16 is sent to the centralized monitoring and control center 400, and the response signal 17 is received from the centralized monitoring and control center 400. At this time, if the communication line for transmitting the confirmation signal 16 and the reply signal 17 fails, the confirmation signal 16b can be sent to the centralized monitoring and control center 400 via the plant 1b as the communication signal 20 as the confirmation signal 16. It is. Similarly,
The answer signal 17 from the central monitoring control center 400 can also be sent to the plant 1 via the plant 1b. It is also possible to exchange signals with the centralized monitoring and control center 400 from the plant 1b via the plant 1. Although FIG. 3 shows only two plants, the plant 1 and the plant 1b, two or more plants may have a similar communication function. According to the second embodiment, even if an abnormality occurs in the confirmation signal 16 and the reply signal 17 directly transmitted and received between the plant 1 and the centralized monitoring control center 400, the confirmation signal 2 is transmitted between the plant 1 and the plant 1b.
0, since the response signal 21 can be transmitted / received, the operation can be reliably performed by the judgment of the person (operator), and the reliability of the unmanned operation of the plant is improved.

FIG. 4 shows a third embodiment of the present invention.
The difference from the first and second embodiments is that an operator 410 in the centralized monitoring and control center 400 is provided with a man-machine interface 450 for inputting and outputting the confirmation signal 16 and the answer signal 17. The first and second
In the embodiment, the operator listens to the voice signal using the telephone as the confirmation signal transmitting / receiving means 230, and transmits the answer signal by pressing the push button of the telephone according to the determined rule. The man-machine interface 450 shown in FIG. 4 is configured to display the contents of the confirmation signal 16 on a screen and to input an answer from the operator 410 using an input device such as a keyboard and a mouse. FIG. 7 shows an example of a display screen of the man-machine interface 450. Mouse cursor 6
By clicking a "data display / answer" button 618 at the top of the screen at 00, the data display screen and the answer input screen are switched. FIG. 7 shows a data display screen. In the abnormal item display window 610, the name of the item determined to be abnormal as a result of the evaluation by the validity evaluation unit 310 is displayed. The data display window 612 displays the generator output and the current value of the power generation amount command for each generator. The graph display window 620 displays the data 616 to be displayed in a time-series graph. The type of data to be displayed in a graph can be selected by clicking the data selection button 614 with a mouse. The types of data include a power generation amount, a turbine rotation speed, a power generation amount command value, an operation frequency correction command, and the like, and can be referred to for each generator. Operator 410
Sees the information on the screen shown in FIG. 7 and the information from the monitoring control device 430 to check whether the operation command input to the operation control device 300 is correct. FIG. 8 shows an example of a screen for inputting an operator's answer. When an answer is selected from the answer selection window 620 and the right selection button 622 is clicked on with a mouse, the answer is selected. In FIG. 8, since "abnormality 2: generator output designation" is selected, an input window 624 for the designated generator output is displayed.
By inputting a value from the keyboard into the generator output input window 624 and clicking the enter button 626, the value of the generator output is determined. When the input is completed, as shown in FIG. 9, a confirmation window 630 is displayed. If the contents are correct, a "send" button 632 is clicked, and if the contents are to be corrected, a "return" button 634 is clicked with a mouse.
Providing the input / output screens as shown in FIGS. 7 and 8 makes it easier for the operator to grasp the contents of the confirmation signal 16 and also makes it easier to input the answer signal. Be accurate.

[0015]

As described above, according to the present invention,
If an operation command input to an unmanned operation plant becomes abnormal for some reason, the operator of the central monitoring and control center is directly inquired by communication means completely different from ordinary communication means, and operation of the plant is determined by the operator. , The reliability of the plant operation can be improved, and the unmanned operation of the plant can be performed safely and accurately. Further, since a plurality of plants can be connected and transmitted and received by completely different communication means from the normal communication means, a communication means for operator inquiry which directly connects the centralized monitoring control center and the plant is provided. Therefore, even if an abnormality occurs, the operation according to the judgment of the operator can be reliably performed, and the reliability of the plant operation can be improved. In addition, since a telephone line and a telephone are used as communication means completely different from ordinary communication means and remote monitoring and control can be performed by direct dialogue with voice, operation errors of the plant 1 can be reduced. Also, by providing the centralized monitoring and control center with a man-machine interface for inputting and outputting the operation command confirmation signal and its response signal, the operator can easily understand the contents of the operation command confirmation signal and input the response signal. As a result, the judgment and response of the operator can be performed quickly and accurately.

[Brief description of the drawings]

FIG. 1 is a remote monitoring control system for a plant according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram of a thermal power plant.

FIG. 3 shows a second embodiment of the present invention.

FIG. 4 shows a third embodiment of the present invention.

FIG. 5 is a diagram illustrating a basic control method of the thermal power plant according to the present invention.

FIG. 6 is a diagram for explaining an evaluation procedure of a validity evaluation unit of the present invention.

FIG. 7 is a diagram showing a data display screen of the present invention.

FIG. 8 is a diagram showing an answer input screen according to the present invention.

FIG. 9 is a diagram showing an answer input confirmation screen of the present invention.

[Explanation of symbols]

10: manipulated variable command, 11: power generation equipment operation data, 12:
Operation command, 13 ... Validity evaluation result, 14 ... Confirmation request signal, 16 ... Confirmation signal, 17 ... Response signal, 100 ... Power generation equipment, 210, 230 ... Confirmation signal transmitting / receiving means, 220, 2
40: normal signal transmitting / receiving means, 300: operation control device, 3
10 ... validity evaluation means, 320 ... operation command confirmation means, 3
30: operation amount calculation means, 400: centralized monitoring control center,
410 ... operator, 420 ... man-machine interface, 430 ... monitoring control device, 440 ... operation command calculation means, 450 ... man-machine interface

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoshio Sato 7-2-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-term in the Electric Power and Electric Development Laboratory, Hitachi, Ltd. 5H223 AA02 BB01 BB08 CC01 DD07 DD09 EE06 EE11 EE29 EE30 5K048 AA07 BA23 DC07 EB02 FA01 GA02 GA14

Claims (5)

[Claims] A monitoring control device in a monitoring control center is connected to a remote plant via a first communication line, and an operation command signal is transmitted from the monitoring control device to the plant.
A control device installed in the plant receives the operation command signal, and in a remote monitoring control system for a plant that operates the plant based on the operation command signal, between the control device in the plant and the monitoring control center A second communication line is provided, and a control device in the plant is provided with an operation command evaluation unit that evaluates the validity of the operation command signal received via the first communication line, and the second communication line A signal transmission / reception means for transmitting an operation command confirmation signal for confirming the validity of the operation command signal via the controller, and receiving an answer signal of an operator in the monitoring control center with respect to the operation command confirmation signal, The monitoring control center includes a signal transmission / reception unit that receives the operation command confirmation signal via the second communication line and transmits the answer signal. A plant remote monitoring and control system, wherein the plant is controlled by a control device in the plant based on an answer signal. 2. A signal transmission / reception means according to claim 1, wherein when there are a plurality of remote plants, a third communication line is provided between each of said plants, and each of said plants is provided with said third communication line via said third communication line. A remote monitoring and control system for a plant. 3. The communication system according to claim 1, wherein the second communication line or the third communication line is a telephone line for a telephone call, and a telephone is transmitted to a signal transmission / reception unit provided in the monitoring control center. A plant remote monitoring and control system, characterized in that it is used. 4. The method according to claim 1, wherein a man-machine interface for inputting / outputting the operation command confirmation signal and the answer signal is connected to a signal transmitting / receiving means provided in the monitoring control center. A remote monitoring and control system for plants. 5. The operation command evaluation means according to claim 1, wherein at least a relation between a system frequency and an operation frequency correction command is appropriate, or a relation between the system frequency and a power generation amount command. A remote monitoring and control system for a plant, which evaluates whether a relationship is appropriate.