JP2000075902A - Basic program automatic adjusting method for plant - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a basic program automatic adjusting method for plant which makes it possible to adjust a basic program in real time during operation and can improve the controllability. SOLUTION: In the case that control variable deviation 6 is generated between a controlled variable 4 and an target value 5 at the time when a basic command 1 is in a setting state and settled and satisfies specific conditions, a break point of a polygonal line function as a basic program set in a function generator 3 is adjusted on the basis of a point corrected with a correction signal 8 based upon the controlled variable deviation 6 and the correction signal 8 outputted from an integrator 9 for correction is reset.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for automatically adjusting a basic program of a plant.

[0002]

2. Description of the Related Art Generally, in a plant such as a thermal power plant, a command value such as a fuel flow rate is obtained by a basic program based on a basic command such as a load command, and an operation amount such as a fuel flow rate matches the command value. By doing so, feedforward control by a so-called basic program for controlling a control amount such as the main steam pressure to a target value such as a set value of the main steam pressure is performed. In the case of feedforward control by such a basic program, The program is set in the function generator in advance and cannot be changed during operation.In the control of the basic program only, when a control amount deviation occurs between the control amount and the target value, Since it cannot be corrected, an integrating circuit for performing the correction is always built-in.

FIG. 4 shows an example of a conventional control device having a function of correcting a control amount deviation while performing feedforward control according to a basic program. The control device includes a basic command 1 (load command). Etc.), a function generator 3 in which a linear function as a basic program for obtaining a basic command value 2 (fuel flow rate or the like) is set, and a control amount 4
(A main steam pressure, etc.) and a control value deviation 6 between a target value 5 (a main steam pressure set value, etc.) and a subtractor 7 for obtaining and outputting the control amount deviation 6, and integrating the control amount deviation 6 output from the subtracter 7 , A correction integrator 9 for outputting a correction signal 8, and a correction signal 8 output from the correction integrator 9 to a basic command value 2 output from the function generator 3. Adder 11 to output, and command value 10 output from adder 11
Between the actual operation amount 12 (fuel flow rate and the like) and the operation amount deviation 13
And a manipulated variable command 15 (an opening command of the fuel flow control valve for performing a proportional integration process of the manipulated variable deviation 13 output from the subtractor 14 to eliminate the manipulated variable deviation 13). Etc.) to a not-shown operation target device (a fuel flow control valve or the like).

In place of the adder 11, the basic command value 2 output from the function generator 3 is multiplied by the correction signal 8 output from the correction integrator 9, and the command value 10 is subtracted from the subtractor 14 In some cases, a multiplier 17 that outputs the data to the input terminal is provided.

In the conventional control device as described above, the basic command value 2 is obtained by a linear function as a basic program set in the function generator 3 based on the basic command 1.
The basic command value 2 is output to the subtracter 14 as the command value 10 via the adder 11, and the subtractor 14 operates the deviation 13 between the command value 10 output from the adder 11 and the actual manipulated variable 12. Is output to the proportional-integral controller 16, and the manipulated variable deviation 13 output from the subtractor 14 is proportionally integrated in the proportional-integral controller 16, and a manipulated variable command for eliminating the manipulated variable deviation 13 15 is output to an operation target device (not shown).

Here, when a control amount deviation 6 occurs between the control amount 4 and the target value 5, the control amount deviation 6 is subtracted by the subtractor 7
Are output to the integrator 9 for correction, the control amount deviation 6 output from the subtracter 7 is integrated in the integrator 9 for correction, and the correction signal 8 is output to the adder 11. The adder 11 adds the correction signal 8 output from the correction integrator 9 to the basic command value 2 output from the function generator 3 to correct the command value 10.

[0007]

However, the correction integrator 9 outputs the correction signal 8 only after the control amount deviation 6 occurs between the control amount 4 and the target value 5. In particular, when the basic command 1 changes, as described above, after a control amount deviation 6 occurs between the control amount 4 and the target value 5, the correction signal 8 from the correction integrator 9 is added to the adder. Outputting to 11 had the disadvantage that the reaction was delayed and controllability was reduced.

Further, in order to change the setting by adjusting the basic program itself, the operation of the plant must be stopped each time, which is not practical.

In view of such circumstances, the present invention enables adjustment of a basic program to be performed in real time during driving.
An object of the present invention is to provide a method of automatically adjusting a basic program of a plant that can improve controllability.

[0010]

According to a first aspect of the present invention, a basic program uses a polygonal line function in which a plurality of folding points are connected to a coordinate system in which a basic command is taken on the X-axis side and a command value is taken on the Y-axis side. A method for automatically adjusting a basic program of a plant, wherein the operation amount is matched with a command value obtained based on a basic command by the basic program, thereby controlling the control amount to a target value. Is settled, and at the time when it coincides with the X-axis coordinate of one breakpoint, if there is a control amount deviation between the control amount and the target value, the point corrected by the correction signal based on the control amount deviation is newly added. And the correction signal is reset, and thereafter, the X-axis at the midpoint between the last-reset folding point and either one of the two adjacent folding points. Previous setting from coordinates When a control amount deviation between the control amount and the target value occurs at the time when the basic command is input into the range up to the X-axis coordinate of either one of the two adjacent break points and the set point is set, In addition, the point corrected by the correction signal based on the control amount deviation and the previously set break point are connected by a straight line, and the straight line and the X point of one of the two adjacent break points of the previously reset break point are connected. The present invention relates to a method for automatically adjusting a basic program of a plant, wherein an intersection with an axis coordinate is reset as a turning point having a new Y-axis coordinate, and the correction signal is reset and repeated.

In the second invention, a basic command is issued to the X-axis side,
In a coordinate system that takes command values on the Y-axis side, a broken line function connecting a plurality of break points is set as a basic program, and the manipulated variable matches the command value obtained based on the basic command by the basic program, This is a method of automatically adjusting the basic program of the plant in which the control amount is controlled to the target value, wherein the basic command is settled, and on the basis of the X-axis coordinate of one turning point, the two adjacent positions of the turning point are used. From the X-axis coordinate at the middle point of either one of the breakpoints, at the time when the basic command is entered within the range from the X-axis coordinate at the middle point of either of the two adjacent breakpoints, When a control amount deviation between the control amount and the target value occurs, a point corrected by the correction signal based on the control amount deviation is reset as a break point having a new Y-axis coordinate, and the correction signal is Reset And, it relates to a basic program automatic adjustment method of the plant, characterized in that repeated.

According to the above means, the following effects can be obtained.

When the basic command is settled and coincides with the X-axis coordinate of one turning point as in the first invention, if a control amount deviation between the control amount and the target value occurs, The point corrected by the correction signal based on the control amount deviation is reset as a break point having a new Y-axis coordinate, and the correction signal is reset. The basic command is entered and settled in the range from the X-axis coordinate at the middle point of either one of the break points to the X-axis coordinate of one of the break points on both sides of the previously set break point. At this point, when a control amount deviation between the control amount and the target value occurs, the point corrected by the correction signal based on the control amount deviation and the break point reset last time are connected by a straight line, and the straight line And either one of both sides of the break point which was reset last time If the intersection of the break point with the X-axis coordinate is reset as a break point having a new Y-axis coordinate, the correction signal is reset, and this is repeated. It is possible to rewrite to the latest state in the form of correction, and as a result, even when the basic command changes, the control amount deviation generated between the control amount and the target value approaches the zero, There is almost no need to output a signal,
Controllability is improved.

As in the second invention, the basic command is settled, and the X-axis coordinate at the midpoint between one of the two adjacent break points on the basis of the X-axis coordinate of one break point is used as a reference. A deviation of the control amount between the control amount and the target value occurs when the basic command is entered within the range up to the X-axis coordinate at the middle point between the other one of the two break points and the other break point. In this case, the point corrected by the correction signal based on the control amount deviation is reset as a break point having a new Y-axis coordinate as it is, and the correction signal is reset and repeated. Can be rewritten to the latest state by always correcting the error. As a result, even when the basic command changes, the control amount deviation generated between the control amount and the target value is substantially reduced. With the shape approaching zero Ri, the correction signal output to be the almost gone, and controllability is improved.

[0015]

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

FIG. 1 shows an example of an embodiment of the present invention. In the figure, portions denoted by the same reference numerals as those in FIG. 4 represent the same components. This embodiment is the same as the first embodiment, except that, as shown in FIG. 1, when the basic instruction 1 is settled and a predetermined condition is satisfied, the control amount 4 and the target value 5 are controlled. When the amount deviation 6 has occurred, based on the point corrected by the correction signal 8 based on the control amount deviation 6, the turning point of the line function as a basic program set in the function generator 3 is adjusted and corrected. The point is that a tuning device 18 for resetting the correction signal 8 output from the integrator 9 is provided.

A single flip-flop 20 is connected to the tuning device 18 via a pulse transmitter 19, and the single flip-flop 20 is set when the basic command 1 is settled,
An output signal 21 of "1" is output to the pulse transmitter 19,
While the pulse signal 22 is output from the pulse transmitter 19 to the tuning device 18, the single flip-flop 20 is reset when the basic command 1 is in the non-settling state, and the output signal 21 is set to “0”. This allows the tuning device 18 to determine whether or not the basic command 1 is in a settling state.

Next, an example of a specific method of adjusting the break point of the broken line function in the tuning device 18 will be described with reference to FIG.

In the example shown in FIG. 2, a plurality of folding points A, B, C and D are connected to a coordinate system in which a basic command 1 is taken on the X-axis side and a basic command value 2 is taken on the Y-axis side. The broken line function is set as a basic program.

First, if none of the breakpoints has been adjusted for the first time, the time when the basic command 1 is settled and coincides with the X-axis coordinate of one breakpoint (the breakpoint B in the example of FIG. 2). In the case where the control amount deviation 6 between the control amount 4 and the target value 5 occurs, the point B ′ (observation data) corrected by the correction signal 8 based on the control amount deviation 6 has a new Y-axis coordinate. The correction signal 8 is reset while setting the break point B again (see FIG. 2).

Thereafter, the fold point B which was previously set again and one of the fold points on both sides of the fold point B (the fold point C in the example of FIG. 2).
At the time when the basic command 1 enters the range from the X-axis coordinate at the middle point of the middle point to the X-axis coordinate of the folding point C (within the range shown in FIG. When a control amount deviation 6 from the target value 5 occurs, a point E (observation data) corrected by the correction signal 8 based on the control amount deviation 6 and a break point B (point B ′) reset previously. And the intersection C ′ between the straight line L and the X-axis coordinate of the break point C is set again as a break point C having a new Y-axis coordinate, and the correction signal 8 is reset. (In FIG. 2,
reference).

As described above, when the folding point C is set again after the folding point B is set, if the X axis coordinate of the point E is too close to the X axis coordinate of the folding point B, A straight line L connecting point B and point E
In this case, the influence of the error becomes large, and the position of the break point C to be reset may be far from the original point. 2, a restriction is imposed on the point in time when the basic command 1 enters the range indicated by and is settled.

After the break point C is set again, the break point C
One of the two adjacent points, ie, the point B or the point D
Can be adjusted and set again in the same manner as described above, but if the next observation data is again within the range indicated by in FIG. 2, the turning point C can be adjusted again. is there.

Hereinafter, by repeating the same operation as described above, it becomes possible to rewrite the broken line function as the basic program to the latest state in such a manner that errors are always corrected.

As a result, even when the basic command 1 changes, the control amount deviation 6 generated between the control amount 4 and the target value 5 becomes substantially zero, and the correction integrator 9 outputs the correction signal. There is almost no need to output 8 to the adder 11, and the controllability is improved.

In this way, adjustment of the basic program can be performed in real time during operation, and controllability can be improved.

FIG. 3 shows another example of a specific method of adjusting the break point of the broken line function in the tuning device 18, which will be described below.

In the example shown in FIG. 3, as in the case of the example of FIG. 2, the basic command 1 is provided on the X-axis side, and the basic command value 2 is provided on the Y-axis side.
, A, B, C, D
Is set as the basic program.

In the case of the example shown in FIG. 3, there is no initial adjustment limitation as in the example of FIG. 2, the basic command 1 is settled, and the X-axis of one break point (the break point C in the example of FIG. 3) is set. On the basis of the coordinates, the X-axis coordinate at the midpoint between one of the two fold points (the fold point B in the example of FIG. 3) on either side of the fold point C is used to determine the other fold point on either side of the fold point C. Point (break point D in the example of FIG. 3)
At the time when the basic command 1 is entered within the range up to the X-axis coordinate at the midpoint (within the range shown in FIG. 3),
When a control amount deviation 6 between the control amount 4 and the target value 5 occurs, the point F (observation data) corrected by the correction signal 8 based on the control amount deviation 6 is used as a turning point having a new Y-axis coordinate. C is reset and the correction signal 8 is reset (see FIG. 2).

After that, the range for determining the breakpoint to be adjusted is updated with the adjusted breakpoint.

Hereinafter, by repeating the same operation as described above, it becomes possible to rewrite the broken line function as the basic program to the latest state in such a manner that errors are always corrected.

As a result, even when the basic command 1 changes, the control variable deviation 6 generated between the control variable 4 and the target value 5 becomes almost zero, and the correction integrator 9 outputs a correction signal. There is almost no need to output 8 to the adder 11, and the controllability is improved.

Thus, in the case of the example shown in FIG.
As in the case of the example, adjustment of the basic program can be performed in real time during operation, and controllability can be improved.

The method for automatically adjusting the basic program of a plant according to the present invention is not limited to the above-described example, and in FIG. 1, an adder 11 or a multiplier 17 is provided downstream of the function generator 3. Has been described, and the correction of the output of the function generator 3 is performed.
The present invention is applicable to the case where the adder 11 or the multiplier 17 is provided on the upstream side to correct the input of the function generator 3 and other various changes can be made without departing from the gist of the present invention. Of course, it can be added.

[0035]

As described above, according to the method for automatically adjusting the basic program of a plant according to the present invention, the basic program can be adjusted in real time during operation, and the controllability can be improved. It can be effective.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a case in which the X-axis coordinate of a break point of a polygonal line function is fixed and the Y-axis coordinate is adjusted in an example of an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a case in which both the X-axis coordinate and the Y-axis coordinate of a break point of a polygonal function are adjusted in an example of an embodiment of the present invention.

FIG. 4 is a block diagram of a conventional example.

[Explanation of symbols]

 Reference Signs List 1 basic command 2 basic command value (command value) 3 function generator 4 control amount 5 target value 6 control amount deviation 8 correction signal 9 correction integrator 10 command value 12 operation amount 18 tuning device A break point B break point B ' Point C Break point C 'intersection D Break point E Point F Point L Straight line

Claims (2)

[Claims] A basic function is set as a basic program in a coordinate system in which a basic command is set on the X-axis side and a command value is set on the Y-axis side. A method of automatically adjusting a basic program of a plant in which a manipulated variable is made to conform to a command value obtained based on the basic command, whereby the control variable is controlled to a target value. If there is a control amount deviation between the control amount and the target value at the time of coincidence with the X-axis coordinate, a point corrected by a correction signal based on the control amount deviation is set as a break point having a new Y-axis coordinate. And resetting the correction signal, and thereafter, based on the X-axis coordinates at the midpoint between the previously set break point and one of the two adjacent break points, the previously set break point Either side of If a control amount deviation between the control amount and the target value occurs at the time when the basic command is input into the range up to the X-axis coordinate of the other turning point and the state is settled, the correction based on the control amount deviation The point corrected by the signal and the previously set break point are connected by a straight line, and the straight line and the X of either one of the two adjacent break points of the previously set break point are connected.
A method of automatically adjusting a basic program of a plant, wherein an intersection with an axis coordinate is reset as a break point having a new Y-axis coordinate, and the correction signal is reset and repeated. 2. A basic command is set as a basic program in a coordinate system in which a basic command is set on the X-axis side and a command value is set on the Y-axis side. A method of automatically adjusting a basic program of a plant in which a manipulated variable is made to conform to a command value obtained based on the basic command, whereby the control variable is controlled to a target value. On the basis of the X-axis coordinate, from the X-axis coordinate at the middle point with either one of the folding points on either side of the folding point, to the X-axis coordinate at the middle point with the other folding point on either side of the folding point. When the control amount deviation between the control amount and the target value occurs at the time when the basic command is entered within the range, the point corrected by the correction signal based on the control amount deviation is directly used as a new Y-axis coordinate. Set as a break point With correct, resets said correction signal, the basic program automatic adjustment method of the plant, characterized in that repeated.