JP2022061660A - Controller and method for control - Google Patents

Abstract

To automatically determine the width of determining a setting according to the nature unique to a transient state of control.SOLUTION: A controller includes: an operation amount calculation unit 1 for calculating an operation amount on the basis of a set value and a control amount and outputting the operation amount to a control target; a setting determination width storing unit 2 for storing a setting determination width; a state determination unit 3 for determining the state of a control system on the basis of the setting determination width; an overshoot amount detection unit 4 for detecting an overshoot amount in making the control amount follow a set value in association with change of the set value; and a setting determination width changing unit 5 for changing the setting determination width stored in the setting determination width storing unit 2 on the basis of the overshoot amount.SELECTED DRAWING: Figure 1

Description

The present invention relates to a control device and a control method having a function of determining the state of a control system.

A set value setting time rate is put into practical use as an index for determining the state of a feedback control system (for example, a PID control system using a temperature controller) applied to a heating device as shown in FIG. 9 (see Patent Document 1). The heating device of FIG. 9 controls a heat treatment furnace 100 that heats the work to be processed, an electric heater 101, a temperature sensor 102 that measures the temperature inside the heat treatment furnace 100, and a temperature inside the heat treatment furnace 100. It is composed of a temperature controller 103, a power regulator 104, a power supply circuit 105, and a PLC (Programmable Logic Controller) 106 that controls the entire heating device. The temperature controller 103 calculates the operation amount MV so that the temperature PV (control amount) measured by the temperature sensor 102 matches the temperature set value SP. The power regulator 104 determines the electric power according to the operation amount MV, and supplies the determined electric power to the electric heater 101 through the electric power supply circuit 105.

The set value settling time rate is the ratio of the time during which the control amount PV is within the settling determination width in the vicinity of the set value SP. By detecting the set value setting time rate, it is possible to detect or predict a problem related to control setting.
In the technique disclosed in Patent Document 1, it is necessary to set a settling determination width for calculating a set value settling time rate. Specifically, a plurality of candidates for the settling judgment width are set in the initial state, the set value settling time rate is calculated for each candidate for the settling judgment width, and an appropriate set value settling time is selected from among the candidates for the plurality of settling judgment widths. It is set by the procedure of selecting the settling judgment width that gives the rate.

For example, in the example of FIG. 10, the settling time TS1 and | SP-PV | in which the absolute value | SP-PV | of the difference between the set value SP and the controlled variable PV is within the settling determination width candidate α1 (for example, α1 = 3 ° C.) The settling time TS2 in which | is within the settling judgment width candidate α2 (for example, α2 = 2 ° C.) and the settling time TS3 in which | SP-PV | is within the settling judgment width candidate α3 (for example, α3 = 1 ° C.) are measured. ing. By dividing the settling time TS1, TS2, and TS3 by the elapsed time of the state in which the temperature controller is executing the control operation, the set value settling time rate RS1, RS2 for each of the settling judgment width candidates α1, α2, and α3. RS3 can be calculated. Then, the settling determination width candidate that gives the optimum set value settling time rate among the set value settling time rates RS1, RS2, and RS3 is determined as the settling determination width. According to Patent Document 1, the settling determination width to be determined does not have to be limited to one stage, and may be a combination of a plurality of stages, or may be determined so as to combine the three stages of the example of FIG.

Even after the settling determination width is set by the process of Patent Document 1 as described above, the settling determination width may become inappropriate depending on the situation. Specifically, regarding the transitional state of control, it is preferable to determine the settling determination width according to the property peculiar to the transient state and calculate the set value settling time rate, but in the technique disclosed in Patent Document 1, the transient state is used. The settling judgment width may be inappropriate without considering the property peculiar to the state. If the settling determination width becomes inappropriate, an erroneous determination may occur regarding the control performance in the transition state, so improvement is required.

Japanese Unexamined Patent Publication No. 2015-06612

The present invention has been made to solve the above problems, and an object of the present invention is to provide a control device and a control method capable of automatically determining a settling determination width according to a property peculiar to a transitional state of control.

The control device of the present invention has an operation amount calculation unit configured to calculate an operation amount based on a set value and a control amount and output it to a controlled object, and a settling determination width configured to store a settling determination width. A storage unit, a state determination unit configured to determine the state of the control system based on the settling determination width, and an overshoot amount in following the control amount to the set value due to a change in the set value are detected. An overshoot amount detection unit configured to change the overshoot amount, and a settling determination width changing unit configured to change the settling determination width stored in the settling determination width storage unit based on the overshoot amount. It is characterized by being prepared.
Further, in one configuration example of the control device of the present invention, the state determination unit includes an elapsed time measuring unit configured to measure the elapsed time of the state in which the control operation by the operation amount calculation unit is being executed. When the settling time measuring unit configured to measure the settling time in which the difference between the set value and the controlled amount is within the settling determination width and the elapsed time reaches a predetermined reference elapsed time. A settling time rate calculation unit configured to calculate a set value settling time rate from the elapsed time and the settling time, a settling time rate storage unit configured to store the set value settling time rate, and an external unit. When a reset signal is received from, or after the set value settling time rate is registered in the settling time rate storage unit, the elapsed time being measured and the resetting unit configured to reset the settling time to zero are provided. It is characterized by being prepared.

Further, in one configuration example of the control device of the present invention, the state of the control system is determined by comparing the set value settling time rate stored in the settling time rate storage unit with a predetermined threshold value. It is characterized by further including a configured determination unit.
Further, in one configuration example of the control device of the present invention, the settling determination width changing unit determines the changed setting determination width by multiplying the overshoot amount by a predetermined proportionality constant. It is a feature.

Further, in the control method of the present invention, the first step of calculating the operation amount based on the set value and the control amount and outputting it to the control target, and the follow-up of the control amount to the set value due to the change of the set value. The second step of detecting the overshoot amount in the above, the third step of changing the settling determination width stored in the settling determination width storage unit based on the overshoot amount, and the control based on the settling determination width. It is characterized by including a fourth step of determining the state of the system.
Further, in one configuration example of the control method of the present invention, the fourth step includes a fifth step for measuring the elapsed time of a state in which the control operation according to the first step is being executed, and the set value. A sixth step of measuring the settling time in which the difference from the controlled amount is within the settling determination width, and setting from the elapsed time and the settling time when the elapsed time reaches a predetermined reference elapsed time. Measured after the seventh step of calculating the value settling time rate and registering it in the settling time rate storage unit, when a reset signal is received from the outside, or after registering the set value settling time rate in the settling time rate storage unit. It is characterized by including the elapsed time in the process and an eighth step of resetting the settling time to zero.

Further, in one configuration example of the control method of the present invention, the state of the control system is determined by comparing the set value settling time rate stored in the settling time rate storage unit with a predetermined threshold value. It is characterized by further including the steps of.
Further, in one configuration example of the control method of the present invention, the third step includes a step of determining the settling determination width after the change by multiplying the overshoot amount by a predetermined proportionality constant. It is characterized by that.

According to the present invention, by providing the overshoot amount detection unit and the settling determination width changing unit, the settling determination width can be automatically determined according to the property peculiar to the transient state of control. As a result, in the present invention, when the state of the control system is determined by using the settling determination width, it is possible to prevent erroneous determination from occurring.

FIG. 1 is a block diagram showing a configuration of a control device according to an embodiment of the present invention. FIG. 2 is a flowchart illustrating the operation of the control device according to the embodiment of the present invention. FIG. 3 is a diagram showing an example of overshoot of the control amount due to the change of the set value. FIG. 4 is a diagram showing a simulation result of a control response when temperature control is executed by the control device according to the embodiment of the present invention. FIG. 5 is a diagram showing a simulation result of a control response when temperature control is executed by the control device according to the embodiment of the present invention. FIG. 6 is a diagram showing a simulation result of a control response when temperature control is executed by the control device according to the embodiment of the present invention. FIG. 7 is an enlarged view of a part of FIGS. 4 to 6. FIG. 8 is a block diagram showing a configuration example of a computer that realizes the control device according to the embodiment of the present invention. FIG. 9 is a block diagram showing the configuration of the heating device. FIG. 10 is a diagram illustrating a procedure for setting a settling determination width in the conventional technique.

[Principle of invention]
Although the behavior of overshoot is generally adopted as an index of the control performance in the transition state, the overshoot itself can be determined by the overshoot rate (see JP-A-2007-264720) or the like. Therefore, it is more effective to pay attention to the property peculiar to the settling time rate. In this case, another notable index in the transition state is the speed of convergence, which can be measured by the time required for convergence when the controlled variable PV draws an exponential trajectory. Specifically, within about 60% of the maximum overshoot amount corresponds to an exponential locus.

[Example]
Hereinafter, examples of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a control device according to an embodiment of the present invention. The control device has an operation amount calculation unit 1 that calculates an operation amount MV based on a set value SP and a control amount PV and outputs it to a control target, a settling determination width storage unit 2 that stores a settling determination width, and a settling determination width. The state determination unit 3 that determines the state of the control system based on the control system, the overshoot amount detection unit 4 that detects the overshoot amount in following the control amount PV to the set value SP due to the change of the set value SP, and the overshoot amount. Based on this, the settling determination width changing unit 5 for changing the settling determination width stored in the settling determination width storage unit 2 is provided.

The operation amount calculation unit 1 is based on the set value input unit 10 for inputting the set value SP from the outside of the control device, the control amount input unit 11 for inputting the control amount PV from a sensor (not shown), and the set value SP and the control amount PV. It is composed of a PID calculation unit 12 for calculating the operation amount MV and an operation amount output unit 13 for outputting the operation amount MV to the control target.

The state determination unit 3 has an elapsed time measuring unit 30 that measures the elapsed time of the state in which the control operation by the operation amount calculation unit 1 is being executed, and the difference between the set value SP and the control amount PV is within the settling determination range. Set by the settling time measurement unit 31 that measures the settling time, and the settling time rate calculation unit 32 that calculates the set value settling time rate from the elapsed time and the settling time when the elapsed time reaches a predetermined reference elapsed time. Elapsed time and settling time during measurement when a reset signal is received from the settling time rate storage unit 33 that stores the value settling time rate, or after the set value settling time rate is registered in the settling time rate storage unit 33. From the reset unit 34 that resets to zero, and the determination unit 35 that determines the state of the control system by comparing the set value settling time rate stored in the settling time rate storage unit 33 with a predetermined threshold value. It is composed.

FIG. 2 is a flowchart illustrating the operation of the control device of this embodiment. Upon receiving the reset signal from the outside in the initial state, the reset unit 34 resets the elapsed time TX measured by the elapsed time measuring unit 30 and the settling time TS1, TS2, TS3 measured by the settling time measuring unit 31 to 0. (FIG. 2, step S100).
The operation when the set value SP of steps S101 to S103 of FIG. 2 is changed will be described later.

The PID calculation unit 12 receives the set value SP input from the set value input unit 10 and the control amount PV input from the control amount input unit 11 as inputs, and performs an operation amount MV by a well-known PID control calculation (feedback control calculation). Is calculated (FIG. 2, step S104).

The operation amount output unit 13 outputs the operation amount MV calculated by the PID calculation unit 12 to the control target (step S105 in FIG. 2). When the control target is, for example, a heating device, the power regulator that supplies electric power to the heater of the heat processing furnace is the actual output destination of the operation amount MV.

When the operation amount calculation unit 1 is executing the control operation, the elapsed time measuring unit 30 updates the elapsed time TX in the state of executing the control operation as shown in the following equation (step S107 in FIG. 2).
TX ← TX + dT ・ ・ ・ (1)
dT is the control cycle. In this way, the elapsed time TX can be measured.

The settling determination width storage unit 2 has a settling determination width α1 = αs1, α2 = αs2, α3 = αs3 (as an initial value) for detecting a defect in a steady state (a state in which the control amount PV is set to the set value SP). (Α1, α2, α3 are real numbers larger than 0) are registered.

In the settling time measuring unit 31, the absolute value of the difference between the set value SP input from the set value input unit 10 and the control amount PV input from the control amount input unit 11 is stored in the settling determination width storage unit 2. If it is within the settling determination width α1 (YES in FIG. 2 step S108), the settling time TS1 corresponding to the settling determination width α1 is updated as shown in the following equation (FIG. 2 step S109).
IF ｜ SP-PV ｜ ≦ α1 THEN TS1 ← TS1 + dT ・ ・ ・ (2)

If the absolute value of the difference between the set value SP and the control amount PV is within the settling determination width α2 stored in the settling determination width storage unit 2 (YES in step S110 of FIG. 2), the settling time measuring unit 31 setstles. The settling time TS2 corresponding to the determination width α2 is updated as shown in the following equation (FIG. 2, step S111).
IF ｜ SP-PV ｜ ≦ α2 THEN TS2 ← TS2 + dT ・ ・ ・ (3)

Further, if the absolute value of the difference between the set value SP and the control amount PV is within the settling determination width α3 stored in the settling determination width storage unit 2, the settling time measuring unit 31 (YES in step S112 in FIG. 2). , The settling time TS3 corresponding to the settling determination width α3 is updated as shown in the following equation (FIG. 2, step S113).
IF ｜ SP-PV ｜ ≦ α3 THEN TS3 ← TS3 + dT ・ ・ ・ (4)

In this way, the settling times TS1, TS2, and TS3 are measured in the same manner as in FIG. When the absolute value of the difference between the set value SP and the control amount PV exceeds the settling determination width α1, the update of the settling time TS1 is temporarily stopped, but as is clear from FIG. 10, the set value SP and the control amount PV When the absolute value of the difference from and is equal to or less than the settling determination width α1, the update of the settling time TS1 is restarted. The same applies to the settling times TS2 and TS3.

In this embodiment, when it is particularly desired to evaluate the transitional state of control, it is preferable to extract and measure the time zone of the settling determination width that is changed according to the transient state as described later.
Therefore, the reset unit 34 sets the elapsed time TX measured by the elapsed time measuring unit 30 when the change of the set value SP is detected by the overshoot amount detecting unit 4 (YES in step S106 of FIG. 2) as described later. The settling time TS1, TS2, and TS3 measured by the settling time measuring unit 31 are reset to 0 (FIG. 2, step S114).

Next, the settling time rate calculation unit 32 sets the set values for each of the settling times TS1, TS2, and TS3 when the elapsed time TX reaches the predetermined reference elapsed time TR (YES in step S115 of FIG. 2). The time rates RS1, RS2, and RS3 are calculated individually (FIG. 2, step S116).
RS1 (%) = (TS1 / TX) x 100 ... (5)
RS2 (%) = (TS2 / TX) x 100 ... (6)
RS3 (%) = (TS3 / TX) x 100 ... (7)

Then, the settling time rate calculation unit 32 registers the calculated set value settling time rate RS1, RS2, RS3 in the settling time rate storage unit 33 (FIG. 2, step S117).
The settling time rate calculation unit 32 sets a reference elapsed time TR suitable for the evaluation period of the transition state of control when a change in the set value SP is detected by the overshoot amount detection unit 4 as described later. After registering the calculated set value settling time rate RS1, RS2, RS3 in the settling time rate storage unit 33, it is desirable to return to the reference elapsed time TR suitable for the evaluation period of the steady state of control.

The determination unit 35 stores the steady state of control, that is, the settling determination width α1 = αs1, α2 = αs2, α3 = αs3 corresponding to the steady state in the settling determination width storage unit 2 (in step S118 of FIG. 2). NO), the state of the control system is determined (FIG. 2, step S119). Specifically, the determination unit 35 has the optimum set value settling time rate among the set value settling time rates RS1, RS2, and RS3 stored in the settling time rate storage unit 33 below the predetermined threshold value THr. When, an alarm is output.

The optimum set value settling time rate means, for example, the set value settling time rate closest to the predetermined index time rate RX (for example, 50%). As an alarm output form, for example, there is an alarm signal output to a higher level PC or the like. The optimum set value settling time rate may be selected once, and the selected set value settling time rate (any of RS1, RS2, RS3) may be compared with the threshold value THr in the subsequent steady state.

After registering the set value setting time rate RS1, RS2, RS3, the reset unit 34 sets the elapsed time TX measured by the elapsed time measuring unit 30 and the setting time TS1, TS2, TS3 measured by the setting time measuring unit 31 to 0. Reset (step S120 in FIG. 2).

Next, the operation when the set value SP is changed will be described. The overshoot amount detection unit 4 detects a change in the set value SP, and detects an overshoot amount in following the set value SP of the control amount PV due to the change in the set value SP. Specifically, when the absolute value of the difference between the set value SP one control cycle before and the set value SP of the current control cycle becomes equal to or higher than the predetermined threshold value THsp, the overshoot amount detection unit 4 It is determined that the set value SP has been changed (YES in step S101 of FIG. 2), and it is determined that the control has transitioned to a transient state (a state of following the changed set value SP).

Then, the overshoot amount detection unit 4 detects the overshoot amount OV of the control amount PV with respect to the set value SP (FIG. 2, step S102). As shown in FIG. 3, the overshoot amount OV is determined when the control amount PV starts to move toward the set value SP after the overshoot occurs in the control amount PV.

The settling determination width changing unit 5 determines the settling determination width α1 = αt1, α2 = αt2, α3 = αt3 according to the overshoot amount OV detected by the overshoot amount detecting unit 4, and setstle determination width storage unit 2. The stored settling determination width α1 = αs1, α2 = αs2, α3 = αs3 is changed to α1 = αt1, α2 = αt2, α3 = αt3 (FIG. 2, step S103).

More specifically, the settling determination width changing unit 5 is based on a predetermined proportionality constant K (K is a real number larger than 0 and smaller than 1), αt1 = KOV, αt2 = 0.67KOV, αt3 = 0.33KOV. It is preferable to determine as follows. That is, the settling determination widths α1, α2, and α3 are defined so as to gradually determine the convergence of the control amount PV after overshoot to the set value SP. The values 0.67 and 0.33 to be multiplied by the overshoot amount OV together with the proportionality constant K are numerical examples for setting the settling determination widths α1, α2, and α3 to values at equal intervals.

In this way, in the transitional state of control, the set value setting time rate RS1, RS2, RS3 is calculated using the setting determination width α1 = αt1, α2 = αt2, α3 = αt3.
In FIG. 2, in order to simplify the description, it is described so that the overshoot amount OV is detected and the settling determination widths α1, α2, and α3 are determined / changed in the control cycle in which the change of the set value SP is detected. However, it goes without saying that it actually takes a plurality of control cycle periods to detect the overshoot amount OV.

The determination unit 35 stores the control transient state, that is, the settling determination width α1 = αt1, α2 = αt2, α3 = αt3 corresponding to the transient state in the settling determination width storage unit 2 (in step S118 of FIG. 2). YES), the state of the control system is determined (FIG. 2, step S121). Specifically, the determination unit 35 compares the set value settling time rate RS1, RS2, RS3 stored in the settling time rate storage unit 33 with the corresponding threshold values THt1, THt2, THt3, and RS1 <THt1, RS2. When at least one of <THt2, RS3 <THt3 is satisfied, an alarm is output.

When the set value setting time rate RS1, RS2, RS3 is registered and the determination process of the determination unit 35 is completed after the settling determination width α1, α2, α3 is changed by the process of step S103. , The settling determination width α1, α2, α3 stored in the settling determination width storage unit 2 is returned to the settling determination width α1 = αs1, α2 = αs2, α3 = αs3 for detecting a defect in a steady state. As a result, in the steady state, the set value setting time rate RS1, RS2, RS3 is calculated using the setting determination width α1 = αs1, α2 = αs2, α3 = αs3.

The processing of steps S101 to S121 as described above is repeatedly executed every control cycle dT until the control operation is completed, for example, by a command from the operator (YES in step S122 of FIG. 2).

4 to 6 are diagrams showing the simulation results of the control response when the temperature control is executed according to this embodiment. The example of FIG. 4 shows the simulation result of the PID control response by the PID parameter with the proportional band 80%, the integration time 100 seconds, and the derivative time 12 seconds, and the example of FIG. 5 shows the proportional band 97%, the integration time 120 seconds, and the derivative. The simulation result of the PID control response by the PID parameter of the time 12 seconds is shown, and the example of FIG. 6 shows the simulation result of the PID control response by the PID parameter of the proportional band 120%, the integration time 150 seconds, and the differentiation time 12 seconds. ..

In any of FIGS. 4 to 6, 100 sec. At the time of, the set value SP is changed from 100 ° C. to 300 ° C., the upper limit of the operation amount MV is 100%, and PID control of different PID parameters is applied to the same control target. In addition, in order to make it easy to compare the state of convergence of the control amount PV to the set value SP after overshoot, the simulation was performed in which the overshoot is about 10 ° C.

FIG. 7 shows 200 sec. Of FIGS. 4 to 6. From 800 sec. It is a figure which expanded the period of. In FIG. 7, in order to distinguish the simulation results of FIGS. 4 to 6, the control amount in the case of FIG. 4 is PV1, the control amount in the case of FIG. 5 is PV2, and the control amount in the case of FIG. 6 is PV3.

Here, the proportionality constant K = 0.6 (corresponding to 60% of the maximum overshoot amount). The settling determination width changing unit 5 determines that α1 = αt1 = 6 ° C., α2 = αt2 = 4 ° C., and α3 = αt3 = 2 ° C. in any of FIGS. 4 to 6. The steady state setting determination width may be about α1 = αs1 = 1.5 ° C., α2 = αs2 = 1 ° C., and α3 = αs3 = 0.5 ° C.

Further, in the simulations of FIGS. 4 to 6, the reference elapsed time TR is set to 600 sec. And said. Therefore, the elapsed time TX in the transition state of control is 100 sec. The measurement was started from the time point, and 700 sec. Reference elapsed time TR = 600 sec. To reach. However, in the following calculation example, 300 sec. 700 sec. 400 sec. Let be the elapsed time TX. Further, the settling time TS1, TS2, TS3 is also set to 300 sec. Measurement shall be started from the time point.

In the case of FIG. 4, the settling time TS1 is 362 sec. 700 sec. Time to time point 338 sec. , The settling time TS2 is 391 sec. 700 sec. Time to time point 309 sec. , Settling time TS3 is 431 sec. 700 sec. Time to time point 269 sec. become.

In the case of FIG. 5, the settling time TS1 is set to 398 sec. In FIG. 700 sec. Time to time 302 sec. , Settling time TS2 is 434 sec. 700 sec. Time to time point 266 sec. , The settling time TS3 is 485 sec. 700 sec. Time to time 215 sec. become.

In the case of FIG. 6, the settling time TS1 is 451 sec. 700 sec. Time to time point 249 sec. , Settling time TS2 is 498 sec. 700 sec. Time to time 202 sec. , Settling time TS3 is 568 sec. 700 sec. Time to time 132 sec. become.

The settling time rate calculation unit 32 has 700 sec. At the time point, the set value setting time rate RS1, RS2, RS3 is calculated from the elapsed time TX and the setting time TS1, TS2, TS3.
In the case of FIG. 4, the set value setting time rate RS1, RS2, RS3 is RS1 = (338/400) × 100 = 84.5%, RS2 = (309/400) = 77.3%, RS3 = (269 /). 400) = 67.3%. In this case, RS1-RS2 = 7.2% and RS2-RS3 = 10.0%.

In the case of FIG. 5, the set value setting time rate RS1, RS2, RS3 is RS1 = (302/400) × 100 = 75.5%, RS2 = (266/400) = 66.5%, RS3 = (215 /). 400) = 53.8%. In this case, RS1-RS2 = 9.0% and RS2-RS3 = 12.7%.

In the case of FIG. 6, the set value setting time rate RS1, RS2, RS3 is RS1 = (249/400) × 100 = 62.3%, RS2 = (202/400) = 50.5%, RS3 = (132 /). 400) = 33.0%. In this case, RS1-RS2 = 11.8% and RS2-RS3 = 17.5%.

The above simulation results are examples that explain the effects of this embodiment in the most concise manner. Since the difference between RS2-RS3 is larger than that of RS1-RS2, it can be quantitatively confirmed that there is a clear difference in the convergence operation in the exponential trajectory after overshoot. That is, according to this embodiment, the set value setting time rate RS1, RS2, RS3 can be utilized as an index of the speed of convergence of the controlled variable PV, and erroneous failure detection due to the property peculiar to the transition state does not occur. Can be done.

In this embodiment, the configuration (state determination unit 3) disclosed in Patent Document 1 is adopted as the state determination technique of the feedback control system, but the present invention is not limited to this, and the present invention uses the settling determination width. It can be applied to all methods for calculating the index for determining the state of the feedback control system. That is, the object of application of the present invention does not have to be the configuration disclosed in Patent Document 1.

The control device described in this embodiment can be realized by a computer provided with a CPU (Central Processing Unit), a storage device, and an interface, and a program for controlling these hardware resources. An example of the configuration of this computer is shown in FIG.

The computer includes a CPU 200, a storage device 201, and an interface device (I / F) 202. For example, a temperature sensor and a power regulator are connected to the I / F 202. In such a computer, a program for realizing the control method of the present embodiment is stored in the storage device 201. The CPU 200 executes the process described in this embodiment according to the program stored in the storage device 201.

The present invention can be applied to a control device.

1 ... Operation amount calculation unit, 2 ... Settlement determination width storage unit, 3 ... State determination unit, 4 ... Overshoot amount detection unit, 5 ... Settlement determination width change unit, 10 ... Set value input unit, 11 ... Control amount input unit , 12 ... PID calculation unit, 13 ... operation amount output unit, 30 ... elapsed time measurement unit, 31 ... settling time measurement unit, 32 ... settling time rate calculation unit, 33 ... settling time rate storage unit, 34 ... reset unit, 35 … Judgment unit.

Claims (8)

An operation amount calculation unit configured to calculate the operation amount based on the set value and control amount and output it to the control target.
A settling judgment width storage unit configured to store the settling judgment width,
A state determination unit configured to determine the state of the control system based on the settling determination width, and
An overshoot amount detection unit configured to detect an overshoot amount in following the control amount to the set value due to a change in the set value.
A control device including a settling determination width changing unit configured to change the settling determination width stored in the settling determination width storage unit based on the overshoot amount. In the control device according to claim 1,
The state determination unit
An elapsed time measuring unit configured to measure the elapsed time of the state in which the control operation by the operation amount calculation unit is being executed, and an elapsed time measuring unit.
A settling time measuring unit configured to measure a settling time in which the difference between the set value and the controlled amount is within the settling determination width.
A settling time rate calculation unit configured to calculate a set value settling time rate from the elapsed time and the settling time when the elapsed time reaches a predetermined reference elapsed time.
A settling time rate storage unit configured to store the set value settling time rate,
A reset unit configured to reset the elapsed time and the settling time during measurement to zero when a reset signal is received from the outside or after the set value settling time rate is registered in the settling time rate storage unit. A control device characterized by being provided with. In the control device according to claim 2,
It is characterized by further including a determination unit configured to determine the state of the control system by comparing the set value settling time rate stored in the settling time rate storage unit with a predetermined threshold value. Control device. In the control device according to any one of claims 1 to 3.
The settling determination width changing unit is a control device characterized in that the settling determination width after the change is determined by multiplying the overshoot amount by a predetermined proportionality constant. The first step of calculating the operation amount based on the set value and the control amount and outputting it to the control target,
The second step of detecting the overshoot amount in following the control amount to the set value due to the change of the set value, and
A third step of changing the settling determination width stored in the settling determination width storage unit based on the overshoot amount, and
A control method comprising a fourth step of determining a state of a control system based on the settling determination width. In the control method according to claim 5,
The fourth step is
The fifth step of measuring the elapsed time of the state in which the control operation according to the first step is being executed, and the fifth step.
The sixth step of measuring the settling time in which the difference between the set value and the controlled amount is within the settling determination width, and
A seventh step of calculating a set value settling time rate from the elapsed time and the settling time and registering the set value in the settling time rate storage unit when the elapsed time reaches a predetermined reference elapsed time.
Includes an eighth step of resetting the elapsed time being measured and the settling time to zero when a reset signal is received from the outside or after the set value settling time rate is registered in the settling time rate storage unit. A control method characterized by. In the control method according to claim 6,
A control method further comprising a ninth step of determining a state of a control system by comparing a set value settling time rate stored in the settling time rate storage unit with a predetermined threshold value. In the control method according to any one of claims 5 to 7.
The third step is a control method comprising a step of determining the settling determination width after the change by multiplying the overshoot amount by a predetermined proportionality constant.

Images