JP2007164568A - Controller and control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the absolute value of steady-state error in a state value control system of a multiloop. <P>SOLUTION: This controller is provided with an error Er1 calculating part 3-1 for calculating an error Er1 between a set value SP1 and a controlled variable PV1 about a first control loop, a PID operating part 4-1 for calculating a manipulated variable MV1 with the error Er1 as an input, a scaling factor A1 operating part 6-1 for multiplying the error Er1 by a preset scaling factor A1, an adding part 7-2 for adding a multiplication result of the scaling factor A1 operating part 6-1 to a set value SP2 of a second control loop in which interference exists between a first control loop and itself to calculate a correction set value SP2x, an error Er2 calculating part 3-2 for calculating an error Er2 between the correction set value SP2x and a controlled variable PV2, and a PID operating part 4-2 for calculating a manipulated variable MV2 with the error Er2 as an input. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a state quantity control technique for a multi-loop control system that controls a plurality of controlled objects.

  For example, there is a furnace as shown in FIG. 12 as a multi-loop temperature control system using an electric heater. In the example of FIG. 12, the interior of the furnace 100 is divided into a first zone Z1, a second zone Z2, and a third zone Z3, and heaters 101, 102, and 103 are installed in the zones Z1, Z2, and Z3, respectively. The temperature is controlled by the controllers 104, 105, and 106. The controllers 104, 105, and 106 measure the temperatures PV1, PV2, and PV3 of the zones Z1, Z2, and Z3, respectively, and the manipulated variable MV1, so that the temperatures PV1, PV2, and PV3 coincide with the set values SP1, SP2, and SP3, respectively. MV2 and MV3 are calculated. The heaters 101, 102, and 103 heat the zones Z1, Z2, and Z3 according to the operation amounts MV1, MV2, and MV3 output from the controllers 104, 105, and 106, respectively. Examples of the controllers 104, 105, and 106 include a commercially available temperature controller, and PID is used as a typical control algorithm.

  Usually, in such a temperature control system, temperature interference occurs between adjacent zones. For example, the heater 101 in the first zone Z1 affects not only the first zone Z1 but also the adjacent second zone Z2 so as to increase the temperature. Similarly, the heater 102 in the second zone Z2 affects the adjacent first and third zones Z1 and Z3, and the heater 103 in the third zone Z3 affects the adjacent second zone Z2. give. Even when there is mutual interference between adjacent zones in this way, in a temperature control system using a conventional controller such as the above-mentioned commercially available temperature controller, each controller has a PID loop that is completely independent for each zone. Will be formed.

On the other hand, the temperatures PV1, PV2, and PV3 of the first, second, and third zones Z1, Z2, and Z3 are almost the same in the transient state at the time of temperature increase by giving an interaction between the multi-loops. Control methods that maintain the values have been proposed (see, for example, Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4).
The control method disclosed in Patent Document 1 calculates an average temperature and a gradient temperature from the temperatures of a plurality of zones to be controlled, calculates an operation amount based on the average temperature and each gradient temperature, By distributing the operation amount to the heaters in each zone so that the temperature control by the controller has no or little effect on the temperature control by the controllers in other zones, non-interference between control loops is realized. is there.

The control methods disclosed in Patent Document 2 and Patent Document 3 automatically synchronize other control loops with the control loop that raises the temperature most slowly.
In the control method disclosed in Patent Document 4, in a multi-loop control system, a state quantity such as a temperature serving as a specific reference is set as a reference state quantity, and a relative amount with respect to the reference state quantity is maintained at a predetermined value. When the state quantity controlled in this way is the follow-up state quantity, the setting value input to the controller that controls the follow-up state quantity is converted into the internal input value and then input to the controller, and this internal input value is calculated. By calculating the internal input value as the sum of the first element with respect to the reference state quantity and the second element with respect to the relative quantity, the relative quantity between the reference state quantity and the tracking state quantity is maintained at a desired value. Control for changing the reference state quantity to a desired value is realized.

Japanese Patent No. 3278807 JP 2005-35090 A JP 2002-49406 A JP 2005-309941 A

  In the multi-loop temperature control system of FIG. 12, for example, when the heater 102 in the second zone Z2 deteriorates and sufficient heater power cannot be exhibited, an output from the controller 105 in the second zone Z2 as shown in FIG. Even if the manipulated variable MV2 is 100% of the upper limit value, the actual temperature PV2 becomes a low value of 190 ° C. with respect to the set value SP2 = 200 ° C., and a steady deviation of 10 ° C. occurs. Similar steady-state deviations can occur not only in temperature but also in control of other state quantities such as humidity.

As described above, when a defect such as heater deterioration or disconnection occurs in the actuator for controlling the state quantity, the controller changes the manipulated variable MV to compensate for this defect, but the manipulated variable MV reaches the upper limit value or the lower limit value. Since this is saturated at the time, the stationary deviation occurs between the set value and the measured state quantity. When the steady deviation exceeds the allowable amount of deviation, for example, if it is a furnace for a manufacturing process, it may be developed into a problem that a defective product is manufactured.
Even if the techniques disclosed in Patent Literature 1 to Patent Literature 4 are applied, the temperature of the other zone is brought close to the temperature of the zone where the steady deviation occurs, so the allowable amount is set. An effect that cancels the steady deviation exceeding the above cannot be obtained.

  The present invention has been made to solve the above-described problem. When a steady deviation is generated in a specific control loop in a multi-loop state quantity control system due to, for example, a deficiency of a control actuator, the absolute value of the steady deviation is reduced. It is an object of the present invention to provide a control device and a control method that can be used.

The present invention relates to a control device of a multi-loop control system having a plurality of control loops that respectively control a plurality of control objects that interfere with each other's control amount, and a deviation occurs between a set value and a control amount. A multiplication unit that multiplies the deviation of the specific control loop by a preset magnification, and another control in which the interference exists between the multiplication result of the multiplication unit and the specific control loop. And an adding unit for adding to the set value of the loop.
The control device according to the present invention includes a first deviation calculating unit that calculates a deviation between a set value and a control amount for a specific control loop, and calculates an operation amount using the deviation of the specific control loop as an input, The interference between the first control operation unit that outputs to the control target of the specific control loop, the magnification operation unit that multiplies the deviation of the specific control loop by a preset magnification, and the specific control loop. Provided in another control loop, and an addition unit that calculates a correction setting value by adding the multiplication result of the magnification calculation unit to the setting value of the corresponding control loop, and the correction setting value for the other control loop A second deviation calculation unit that calculates a deviation between the control amount and a control amount, and a second control calculation unit that calculates an operation amount using the deviation of the other control loop as an input and outputs the operation amount to a control target of the other control loop Are provided.
The control device of the present invention calculates a deviation between a corrected set value obtained by correcting a set value for each control loop and a control amount, and calculates an operation amount using the deviation as an input for each control loop. Between the control calculation unit that outputs to the control target of the corresponding control loop, the multiplication calculation unit that multiplies the deviation by a preset magnification for each control loop, and the set value for each control loop between this control loop And an addition unit that calculates the correction setting value by adding the multiplication results of the other control loops in which the interference exists.
Further, in one configuration example of the control device of the present invention, when the deviation is received and output for each control loop, a dead zone processing unit that sets the deviation to 0 when the absolute value of the deviation is smaller than a specific value. An upper / lower limit processing unit for performing upper / lower limit processing for limiting the deviation output from the dead zone processing unit for each control loop within a range between a preset upper limit value and lower limit value, and the operation amount for each control loop And an operation amount saturation determination unit for notifying the magnification calculation unit of the corresponding control loop of the determination result, and the magnification calculation unit of the corresponding control loop When it is determined that the manipulated variable has reached the upper and lower limit values, the upper and lower limit processed deviation of the corresponding control loop is multiplied by a preset magnification, and a multiplication result is output, and the corresponding control loop The operation amount of If it is determined that to not, the multiplication result is to zero.

Further, the control method of the present invention includes a magnification calculation procedure for multiplying the deviation of a specific control loop in which a deviation is generated between a set value and a control amount by a preset magnification, and the magnification calculation procedure. An addition procedure for adding a multiplication result to a set value of another control loop in which the interference exists with the specific control loop.
In the control method of the present invention, a first deviation calculating procedure for calculating a deviation between a set value and a control amount for a specific control loop, and calculating an operation amount using the deviation of the specific control loop as an input, The interference between the first control calculation procedure to be output to the control target of the specific control loop, the magnification calculation procedure for multiplying the deviation of the specific control loop by a preset magnification, and the specific control loop An addition procedure for calculating a correction setting value by adding the multiplication result of the magnification calculation procedure to a setting value of another control loop in which the difference exists, and calculating a deviation between the correction setting value and the control amount for the other control loop The second deviation calculation procedure to be executed and the control calculation procedure for calculating the operation amount with the deviation of the other control loop as an input and outputting it to the control target of the other control loop are repeatedly executed. .
Further, the control method of the present invention calculates a deviation between a correction set value obtained by correcting a set value for each control loop and a control amount, and calculates an operation amount using the deviation as an input for each control loop. Between the control calculation procedure to be output to the control target of the corresponding control loop, the magnification calculation procedure for multiplying the deviation by a preset magnification for each control loop, and the set value for each control loop between this control loop An addition procedure for calculating the correction set value by adding the multiplication results for the other control loops in which the interference exists is repeatedly executed.
Further, in one configuration example of the control method of the present invention, when the deviation is received and output for each control loop, a dead zone processing procedure for setting the deviation to 0 when the absolute value of the deviation is smaller than a specific value. And an upper / lower limit processing procedure for executing upper / lower limit processing for limiting the deviation output in the dead zone processing procedure for each control loop within a preset upper limit value and lower limit value range, and the manipulated variable for each control loop. An operation amount saturation determination procedure for determining whether or not the upper and lower limit values have been reached, and when the magnification calculation procedure determines that the operation amount of the corresponding control loop has reached the upper and lower limit values. When the upper and lower limit processed deviation of the corresponding control loop is multiplied by a preset magnification and a multiplication result is output, and it is determined that the operation amount of the corresponding control loop has not reached the upper and lower limit value Sets the multiplication result to 0 In which was to so that.

  According to the present invention, the deviation of a specific control loop in which a steady-state deviation occurs is multiplied by a preset magnification, and this multiplication result is used for another control in which interference exists with the specific control loop. By correcting the set value by adding it to the set value of the loop, the deviation of the operation amount of the other control loop based on the corrected set value affects the direction of reducing the steady error of the specific control loop. It is possible to realize a cooperative operation that reduces the absolute value of.

  Further, in the present invention, by providing a magnification calculating unit and an adding unit for each control loop, it is possible to influence the direction of reducing the mutual steady deviation between a plurality of control loops that interfere with each other. As a result, the absolute value of the steady deviation of the plurality of control loops can be reduced.

  Further, in the present invention, the magnification calculation unit according to the determination result of the operation amount saturation determination unit multiplies the deviation by a preset magnification when the operation amount has reached the upper and lower limit values, and the operation amount exceeds the upper and lower limit values. When the value does not reach the value, the multiplication result is set to 0, so that the operation of the control device can be appropriately switched according to the operation amount. Further, in the present invention, by providing the dead zone processing unit, the cooperative operation between the multi-loops can be turned off when the steady deviation is very small. In the present invention, by providing an upper and lower limit processing unit, it is possible to prevent the correction set value from deviating too much from the original set value when the steady-state deviation is extremely large.

[Principle of the Invention]
The present invention focuses on inter-zone interference in a multi-loop state quantity control system. That is, in the control loop of a zone adjacent to the zone of the specific control loop in which the steady deviation Er has occurred, if the set value slightly deviates from the original set value SP ′, the manipulated variable MV ′ deviates from the original value and is output. In view of this, it is noted that the deviation of the manipulated variable MV ′ can affect the direction in which the steady deviation Er of a specific control loop is reduced by inter-zone interference.

  Specifically, when Er = SP-PV (SP is a set value of a specific control loop and PV is a control amount of the specific control loop) is generated in a specific control loop, the control loop of the adjacent zone The steady-state deviation Er is reduced by correcting the set value SP ′ in a direction opposite to the direction of the control amount PV viewed from the set value SP of the specific control loop. In order to automatically reduce such steady-state deviation Er, an amount obtained by correcting the steady-state deviation Er with a specific magnification may be added to the set value SP '.

  It is also effective to monitor the steady-state deviation Er and automatically correct the operation amount MV ′ of the adjacent zone. However, when feedback control such as PID is applied to the control loop of the adjacent zone, the operation amount Since automatic correction of MV ′ is compensated by feedback control, it is not practical. The present invention is characterized in that the steady-state error Er is reflected in the set value SP ′ of the control loop of the adjacent zone.

  The state quantity includes, for example, temperature, pressure, flow rate, and the like. Here, the principle of the present invention and its effect will be described more specifically by taking temperature control as an example. As shown in FIG. 13, the manipulated variable MV2 output from the controller 105 in the second zone Z2 has an upper limit value of 100%, and a steady deviation of Er2 = SP2-PV2 = 200 ° C.-190 ° C. = 10 ° C. occurs. Suppose you are. At this time, in the first and third zones Z1 and Z3, while the set values SP1 and SP3 are both 200 ° C., the control amounts (temperatures) PV1 and PV3 are also 200 ° C. MV1 and MV3 are 60%. Note that the average temperature of the first, second, and third zones Z1, Z2, and Z3 is (200 + 190 + 200) /3=196.7° C. when viewed in the entire interior of the furnace 100.

  For example, when 0.6 times the steady deviation Er2 of the second zone Z2 is added to the set values SP1 and SP3 of the adjacent first and third zones Z1 and Z3, the set values SP1 and SP3 are 206. As a result, the manipulated variables MV1 and MV3 also increase from 60% (for example, MV1 = MV3 = 70%). Since the increase in the manipulated variables MV1 and MV3 affects the temperature PV2 in the second zone Z2 due to temperature interference between the zones, the temperature PV2 also increases. Thereafter, as shown in FIG. 1, for example, the set values SP1 and SP3 of the first and third zones Z1 and Z3 are 203 ° C., the temperatures PV1 and PV3 are also 203 ° C., and the second zone Z2 The steady-state deviation Er2 = SP2-PV2 = 200.degree. C.-195.degree. C. = 5.degree. C., so that 0.6 times the steady deviation Er2 of the second zone Z2 is equal to that of the first and third zones Z1, Z3. The temperature control converges to the equilibrium point added to the set values SP1 and SP3.

  In this case, for the first and third zones Z1 and Z3, although the initial set values SP1 and SP3 were 200 ° C., a steady deviation of 3 ° C. occurred, Since the steady deviation of the zone Z2 is reduced to 5 ° C., the large steady deviation is improved. Even in the entire interior of the furnace 100, the average temperature of the first, second, and third zones Z1, Z2, and Z3 is (203 + 195 + 203) /3=200.3° C. It can be said that the temperature is improved from 196.7 ° C.

  Based on the principle as described above, it is possible to realize a cooperative operation for reducing the absolute value of the steady-state deviation occurring in a specific control loop in the multi-loop state quantity control system. The present invention uses a state quantity control device 107 (such as a commercially available multi-loop controller) that handles cooperative operations between multi-loops as shown in FIG.

[First Embodiment]
FIG. 2 is a block diagram showing the configuration of the state quantity control device according to the first embodiment of the present invention, and FIG. 3 is a flowchart showing the operation of the state quantity control device of FIG. The present embodiment shows the minimum configuration of the state quantity control device of the present invention, and assumes that a steady deviation occurs only in the specific first control loop.

  The state quantity control device according to the present embodiment includes a set value SP1 input unit 1-1, a control amount PV1 input unit 2-1, and a set value SP1 of the first control loop as the configuration related to the first control loop. A deviation Er1 calculating unit 3-1 for calculating a deviation Er1 with respect to the control amount PV1, a PID calculating unit 4 for calculating the operation amount MV1 by PID control calculation with the deviation Er1 as an input, and further executing upper and lower limit processing of the operation amount MV1. -1 and the manipulated variable MV1 output unit 5-1, and the configuration relating to the second control loop includes a set value SP2 input unit 1-2, a control amount PV2 input unit 2-2, and a second control loop. A deviation Er2 calculation unit 3-2 that calculates a deviation Er2 between the correction setting value SP2x obtained by correcting the setting value SP2 and the control amount PV2, and an operation amount MV2 is calculated by PID control calculation using the deviation Er2 as an input. It includes a PID calculation unit 4-2 to execute the upper and lower limit processing MV2, and a manipulated variable MV2 output unit 5-2.

  Furthermore, the state quantity control device of the present embodiment is configured as a configuration related to the cooperative operation between the multi-loops, a magnification A1 calculation unit 6-1 that multiplies the deviation Er1 by a preset magnification A1, and a magnification A1 to the set value SP2. An addition unit 7-2 that adds the multiplication results of the calculation unit 6-1 and calculates the correction set value SP2x.

  FIG. 4 is a block diagram of the multi-loop state quantity control system of the present embodiment. In FIG. 4, P1 is a control target of the first control loop, and P2 is a control target of the second control loop. Although not explicitly shown in FIG. 4, there is interference between the first control loop and the second control loop that affects the mutual control amount.

Next, the operation of the state quantity control device of the present embodiment will be described with reference to FIG. The set value SP1, which is the required value of the state quantity of the first control loop, is set by the operator of the control device and input to the deviation Er1 calculating unit 3-1 via the set value SP1 input unit 1-1 (FIG. 3 step S100).
The control amount PV1, which is a measurement value of the state quantity of the first control loop, is measured by a first measurement unit (not shown) and is input to the deviation Er1 calculation unit 3-1 via the control amount PV1 input unit 2-1. (Step S101).
The deviation Er1 calculation unit 3-1 calculates the deviation Er1 between the set value SP1 and the control amount PV1 by the following equation (step S102).
Er1 = SP1-PV1 (1)

Next, the PID calculation unit 4-1 calculates the manipulated variable MV <b> 1 by performing a PID control calculation such as the following transfer function equation with the deviation Er <b> 1 as an input (step S <b> 103).
MV1 = (100 / Pb1) {1+ (1 / Ti1s) + Td1s} Er1 (2)
In Expression (2), Pb1 is a proportional band, Ti1 is an integration time, Td1 is a differentiation time, and s is a Laplace operator. When the calculated operation amount MV1 is smaller than the preset output lower limit value OL1, the PID calculation unit 4-1 sets the operation amount MV1 = OL1 and the calculated operation amount MV1 is greater than the preset output upper limit value OH1. If larger, an operation amount upper / lower limit process is performed with the operation amount MV1 = OH1.

The manipulated variable MV1 output unit 5-1 outputs the manipulated variable MV1 output from the PID calculating unit 4-1 to a control actuator (not shown) of the first control loop (step S104). The control actuator operates to control the state quantity of the first control loop based on the operation quantity MV1.
The magnification A1 calculation unit 6-1 multiplies the deviation Er1 by a preset magnification A1, and outputs a multiplication result A1Er1 (step S105). A value in the range of 0 <A1 <1 is usually used as the value of the magnification A1. When A1 = 0, it is the same as when the present invention is not applied, and the effect of reducing the steady-state deviation increases as the value of the magnification A1 approaches 1.

On the other hand, the set value SP2, which is the required value of the state quantity of the second control loop, is set by the operator of the control device and is input to the adder 7-2 via the set value SP2 input unit 1-2 (step). S106).
The control amount PV2, which is a measurement value of the state quantity of the second control loop, is measured by a second measuring unit (not shown) and is input to the deviation Er2 calculation unit 3-2 via the control amount PV2 input unit 2-2. (Step S107).

The adding unit 7-2 adds the multiplication result A1Er1 of the magnification A1 calculating unit 6-1 to the set value SP2 to calculate the corrected set value SP2x as in the following equation (step S108).
SP2x = SP2 + A1Er1 (3)
The deviation Er2 calculation unit 3-2 calculates the deviation Er2 between the correction set value SP2x and the control amount PV2 by the following equation (step S109).
Er2 = SP2x-PV2 (4)

Next, the PID calculation unit 4-2 receives the deviation Er2 and performs a PID control calculation like the following transfer function equation to calculate the manipulated variable MV2 (step S110).
MV2 = (100 / Pb2) {1+ (1 / Ti2s) + Td2s} Er2 (5)
In Expression (5), Pb2 is a proportional band, Ti2 is an integration time, and Td2 is a differentiation time. When the calculated operation amount MV2 is smaller than the preset output lower limit value OL2, the PID calculation unit 4-2 sets the operation amount MV2 = OL2 and the calculated operation amount MV2 is greater than the preset output upper limit value OH2. If larger, an operation amount upper / lower limit process is performed with the operation amount MV2 = OH2.

The manipulated variable MV2 output unit 5-2 outputs the manipulated variable MV2 output from the PID calculating unit 4-2 to a control actuator (not shown) of the second control loop (step S111). The control actuator operates to control the state quantity of the second control loop based on the operation quantity MV2.
The processes in steps S100 to S111 as described above are repeatedly executed for each control cycle until the operator instructs the end of the control (YES in step S112).

  In the present embodiment, the deviation Er1 of the specific first control loop in which the steady deviation is generated is multiplied by the magnification A1, and the multiplication result A1Er1 is added to the set value SP2 to correct the set value SP2. Since the deviation of the operation amount MV2 of the second control loop based on the correction setting value SP2x affects the direction of reducing the steady deviation Er1 of the first control loop, the cooperative operation for reducing the absolute value of the steady deviation Er1 is performed. Can be realized. As a result, when a defect such as deterioration or disconnection of the heater in temperature control occurs in the control actuator, the absolute value of the steady deviation due to the defect in the control actuator can be reduced.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. FIG. 5 is a block diagram showing the configuration of the state quantity control device according to the second embodiment of the present invention, and FIG. 6 is a flowchart showing the operation of the state quantity control device of FIG. The present embodiment shows a minimum configuration that operates in both directions, and assumes that a steady deviation occurs in both the first control loop and the second control loop.

  The state quantity control device according to the present embodiment includes a set value SP1 input unit 11-1, a control quantity PV1 input unit 12-1, and a set value SP1 of the first control loop as the configuration related to the first control loop. A deviation Er1 calculation unit 13-1, a PID calculation unit 14-1, and an operation amount MV1 output unit 15-1 for calculating a deviation Er1 between the corrected correction set value SP1x and the control amount PV1 are provided, and a second control is provided. As a configuration relating to the loop, a deviation Er2 between the set value SP2 input unit 11-2, the control amount PV2 input unit 12-2, the correction set value SP2x obtained by correcting the set value SP2 of the second control loop, and the control amount PV2 is set. A deviation Er2 calculation unit 13-2 to be calculated, a PID calculation unit 14-2, and an operation amount MV2 output unit 15-2 are provided.

  Furthermore, the state quantity control device according to the present embodiment has a magnification A1 calculation unit 16-1 that multiplies the deviation Er1 by a preset magnification A1 and a deviation Er2 as a configuration related to the cooperative operation between the multi-loops. A magnification A2 calculation unit 16-2 that multiplies the magnification A2 and an addition unit 17-1 that calculates a correction set value SP1x by adding the multiplication result one control cycle before the magnification A2 calculation unit 16-2 to the set value SP1. And an addition unit 17-2 that calculates the correction set value SP2x by adding the multiplication result of the magnification A1 calculation unit 6-1 to the set value SP2.

  FIG. 7 is a block diagram of the multi-loop state quantity control system of the present embodiment. Similar to the case of FIG. 4, there is interference between the first control loop and the second control loop that affects the mutual control amount.

Next, the operation of the state quantity control device of the present embodiment will be described with reference to FIG. The set value SP1 of the first control loop is set by the operator and is input to the adder 17-1 via the set value SP1 input unit 11-1 (step S200 in FIG. 6).
The control amount PV1 of the first control loop is measured by a first measuring unit (not shown) and is input to the deviation Er1 calculation unit 13-1 via the control amount PV1 input unit 12-1 (step S201).

The adder 17-1 adds the multiplication result A2Er2 before one control cycle of the magnification A2 calculator 16-2 to the set value SP1 to calculate the corrected set value SP1x as shown in the following equation (step S202).
SP1x = SP1 + A2Er2 (6)
The deviation Er1 calculation unit 13-1 calculates the deviation Er1 between the correction set value SP1x and the control amount PV1 by the following equation (step S203).
Er1 = SP1x-PV1 (7)

Next, similarly to the PID calculation unit 4-1, the PID calculation unit 14-1 calculates the manipulated variable MV1 by the PID control calculation using the deviation Er1 as an input, and further executes the upper and lower limit processing of the manipulated variable MV1 (step). S204).
The manipulated variable MV1 output unit 15-1 outputs the manipulated variable MV1 output from the PID calculating unit 14-1 to a control actuator (not shown) of the first control loop (step S205).
Similar to the magnification A1 calculation unit 6-1, the magnification A1 calculation unit 16-1 multiplies the deviation Er1 by a preset magnification A1 and outputs a multiplication result A1Er1 (step S206).

On the other hand, the set value SP2 of the second control loop is set by the operator and is input to the adder 17-2 via the set value SP2 input unit 11-2 (step S207).
The control amount PV2 of the second control loop is measured by a second measurement unit (not shown) and is input to the deviation Er2 calculation unit 13-2 via the control amount PV2 input unit 12-2 (step S208).

Similarly to the adding unit 7-2, the adding unit 17-2 adds the multiplication result A1Er1 of the magnification A1 calculating unit 16-1 to the set value SP2 to calculate a corrected set value SP2x (step S209).
The deviation Er2 calculation unit 13-2 calculates the deviation Er2 between the correction set value SP2x and the control amount PV2 in the same manner as the deviation Er2 calculation unit 3-2 (step S210).

Next, similarly to the PID calculation unit 4-2, the PID calculation unit 14-2 calculates the operation amount MV2 by the PID control calculation with the deviation Er 2 as an input, and further executes the upper and lower limit processing of the operation amount MV 2 (step) S211).
The manipulated variable MV2 output unit 15-2 outputs the manipulated variable MV2 output from the PID calculating unit 14-2 to a control actuator (not shown) of the second control loop (step S212).

The magnification A2 calculating unit 16-2 multiplies the deviation Er2 by a preset magnification A2, and outputs a multiplication result A2Er2 (step S213). A value in the range of 0 <A2 <1 is usually used as the value of the magnification A2. When A2 = 0, it is the same as when the present invention is not applied, and the effect of reducing the steady-state deviation increases as the value of the magnification A2 approaches 1.
The processes in steps S200 to S213 as described above are repeatedly executed for each control cycle until the operator instructs the end of the control (YES in step S214).

  In the present embodiment, the deviation Er1 is multiplied by the magnification A1, and the multiplication result A1Er1 is added to the set value SP2 to correct the set value SP2, and the deviation Er2 is multiplied by the magnification A2 to set the multiplication result A2Er2. By correcting the set value SP1 by adding to the value SP1, the deviation of the operation amount MV2 of the second control loop based on the corrected set value SP2x affects the direction of reducing the steady deviation Er1 of the first control loop. At the same time, the deviation of the manipulated variable MV1 of the first control loop based on the correction set value SP1x affects the direction of reducing the steady deviation Er2 of the second control loop, so the absolute values of the steady deviations Er1 and Er2 are reduced. Cooperative operation can be realized.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. FIG. 8 is a block diagram showing the configuration of the state quantity control device according to the third embodiment of the present invention, and FIG. 9 is a flowchart showing the operation of the state quantity control device of FIG. In the present embodiment, the present invention is applied to the multi-loop temperature control system of FIG.

  The state quantity control device of the present embodiment has a set value SP1 input unit 21-1, a control quantity PV1 input unit 22-1, and a set value SP1 of the first control loop as the configuration related to the first control loop. A deviation Er1 calculation unit 23-1, a PID calculation unit 24-1, and an operation amount MV1 output unit 25-1 for calculating a deviation Er1 between the corrected correction set value SP1x and the control amount PV1 are provided, and the second control. As a configuration relating to the loop, a deviation Er2 between the set value SP2 input unit 21-2, the control amount PV2 input unit 22-2, the correction set value SP2x obtained by correcting the set value SP2 of the second control loop, and the control amount PV2 is set. A deviation Er2 calculation unit 23-2 to be calculated, a PID calculation unit 24-2, and an operation amount MV2 output unit 25-2 are provided. As a configuration related to the third control loop, a set value SP3 input unit 21-3, Control amount P 3 input unit 22-3, deviation Er3 calculation unit 23-3 for calculating deviation Er3 between correction set value SP3x obtained by correcting set value SP3 of the third control loop and control amount PV3, and PID with deviation Er3 as an input An operation amount MV3 is calculated by a control operation, and further includes a PID operation unit 24-3 that executes upper and lower limit processing of the operation amount MV3, and an operation amount MV3 output unit 25-3.

  Further, the state quantity control device according to the present embodiment has a configuration related to the cooperative operation between the multi-loops. When the manipulated variable MV1 has reached the upper and lower limit values, the upper limit / lower limit processed deviation Er1 described later is multiplied by the magnification A1. When the manipulated variable MV1 does not reach the upper / lower limit value, the magnification A1 calculating unit 26-1 sets the multiplication result to 0, and when the manipulated variable MV2 reaches the upper / lower limit value, upper / lower limit processing described later is performed. When the deviation Er2 is multiplied by the magnification A2 and the manipulated variable MV2 has not reached the upper / lower limit value, the magnification A2 calculating unit 26-2 that makes the multiplication result 0, and when the manipulated variable MV3 has reached the upper / lower limit value A deviation Er3, which will be described later, is multiplied by a magnification A3. If the manipulated variable MV3 does not reach the upper / lower limit value, a multiplication A3 calculating unit 26-3 that sets the multiplication result to 0, and a setting value SP1 with a magnification A2 One system of calculation unit 26-2 An addition unit 27-1 that calculates the correction set value SP1x by adding the multiplication results before the cycle, adds the multiplication result of the magnification A1 calculation unit 26-1 to the set value SP2, and further adds the multiplication result of the magnification A3 calculation unit 26-3. An addition unit 27-2 that calculates the correction set value SP2x by adding the multiplication results of one control cycle before, and calculates the correction set value SP3x by adding the multiplication result of the magnification A2 calculation unit 26-2 to the set value SP3. When the absolute value of the deviation Er1 is smaller than a specific value when the deviation Er1 is received and output, the adder 27-3, the dead zone processing unit 28-1 that sets the deviation Er1 to 0, and the deviation Er2 are received and output. When the absolute value of the deviation Er2 is smaller than the specific value, the dead zone processing unit 28-2 that sets the deviation Er2 to 0, and when the deviation Er3 is received and output, the absolute value of the deviation Er3 is smaller than the specific value. From the dead zone processing unit 28-3 that sets the deviation Er3 to 0, the upper and lower limit processing unit 29-1 that executes the upper and lower limit processing of the deviation Er1 output from the dead zone processing unit 28-1, and the dead zone processing unit 28-2. Upper / lower limit processing unit 29-2 for executing upper / lower limit processing of output deviation Er2, upper / lower limit processing unit 29-3 for executing upper / lower limit processing of deviation Er3 output from dead zone processing unit 28-3, and operation The operation amount MV1 saturation determination unit 30-1 that determines whether or not the amount MV1 has reached the upper and lower limit values and notifies the magnification A1 calculation unit 26-1 of the determination result, and the operation amount MV2 has reached the upper and lower limit values. An operation amount MV2 saturation determination unit 30-2 for notifying the magnification A2 calculation unit 26-2 of the determination result, and determining whether the operation amount MV3 has reached the upper and lower limit values. The determination result is passed to the magnification A3 calculation unit 26-3. And an operation amount MV3 saturation determination unit 30-3 to be known.

  FIG. 10 is a block diagram of the multi-loop state quantity control system of the present embodiment. There is interference between the first control loop and the second control loop that affects the mutual control amount, and there is also interference between the second control loop and the third control loop. .

Next, the operation of the state quantity control device of the present embodiment will be described with reference to FIG. The set value SP1 of the first control loop is set by the operator and is input to the adder 27-1 via the set value SP1 input unit 21-1 (step S300 in FIG. 9).
The control amount PV1 of the first control loop is measured by a first measurement unit (not shown) and is input to the deviation Er1 calculation unit 23-1 via the control amount PV1 input unit 22-1 (step S301).

Similar to the adding unit 17-1, the adding unit 27-1 adds the multiplication result A2Er2 before one control cycle of the magnification A2 calculating unit 26-2 to the set value SP1 to calculate the corrected set value SP1x (step S302). ).
The deviation Er1 calculation unit 23-1 calculates the deviation Er1 between the correction set value SP1x and the control amount PV1 in the same manner as the deviation Er1 calculation unit 13-1 (step S303).

Next, similarly to the PID calculation unit 4-1, the PID calculation unit 24-1 calculates the operation amount MV1 by the PID control calculation with the deviation Er1 calculated by the deviation Er1 calculation unit 23-1 as an input, and further performs the operation. The upper and lower limit processing of the amount MV1 is executed (step S304).
The manipulated variable MV1 output unit 25-1 outputs the manipulated variable MV1 output from the PID calculating unit 24-1 to a control actuator (not shown) of the first control loop (step S305).

When the absolute value of the deviation Er1 calculated by the deviation Er1 calculation unit 23-1 is smaller than a specific value (dead zone R1), the dead zone processing unit 28-1 outputs the deviation Er1 output to the upper / lower limit processing unit 29-1. Set to 0 (step S306). Specifically, the dead zone processing unit 28-1 executes the following expression.
IF | Er1 | <R1 THEN Er1 = 0
ELSEIF Er1> 0 THEN Er1 ← Er1-R1
ELSEIF Er1 <0 THEN Er1 ← Er1 + R1 (8)

  According to Equation (8), when | Er1 | ≧ R1 and Er1> 0, the dead zone R1 is subtracted from the deviation Er1, while when | Er1 | ≧ R1 and Er1 <0, the dead zone R1 is added to the deviation Er1. (Processing following two ELSEIF statements in equation (8)). The reason is that when such processing is not performed, the deviation Er1 after the dead zone processing becomes discontinuous depending on whether or not the condition | Er1 | <R1 is satisfied. Therefore, even when the condition of | Er1 | <R1 is not satisfied, the deviation Er1 after the dead zone process is made continuous by making the absolute value of the deviation Er1 smaller by the dead zone R1.

The upper / lower limit processing unit 29-1 sets Er1 = H1 when the deviation Er1 output from the dead zone processing unit 28-1 is larger than the preset upper limit value H1, and the deviation Er1 output from the dead zone processing unit 28-1. Is smaller than the preset lower limit value L1, deviation upper and lower limit processing is executed with Er1 = L1 (step S307). That is, the upper / lower limit processing unit 29-1 executes the following expression.
IF Er1> H1 THEN Er1 = H1 (9)
IF Er1 <L1 THEN Er1 = L1 (10)

The operation amount MV1 saturation determination unit 30-1 determines whether or not the operation amount MV1 has reached the upper limit value OH1 or the lower limit value OL1, and sends the determination result to the magnification A1 calculation unit 26-1 (step S308).
When it is determined that the manipulated variable MV1 has reached the upper limit value OH1 or the lower limit value OL1, the magnification A1 calculating unit 26-1 is set to the magnification Er1 output in advance from the upper / lower limit processing unit 29-1. Multiplying A1, the multiplication result A1Er1 is output, and when it is determined that the manipulated variable MV1 has not reached either the upper limit value OH1 or the lower limit value OL1, the multiplication result A1Er1 is set to 0 (step S309). . A value in the range of 0 <A1 <1 is usually used as the value of the magnification A1. Needless to say, the process of setting the multiplication result A1Er1 to 0 is a process corresponding to A1 = 0.

On the other hand, the set value SP2 of the second control loop is set by the operator and is input to the adder 27-2 via the set value SP2 input unit 21-2 (step S310).
The control amount PV2 of the second control loop is measured by a second measurement unit (not shown) and is input to the deviation Er2 calculation unit 23-2 via the control amount PV2 input unit 22-2 (step S311).

The adding unit 27-2 adds the multiplication result A1Er1 of the magnification A1 calculating unit 26-1 to the set value SP2, and further adds the multiplication result A3Er3 of one magnification before the control cycle of the magnification A3 calculating unit 26-3. Thus, the correction set value SP2x is calculated (step S312).
SP2x = SP2 + A1Er1 + A3Er3 (11)
The deviation Er2 calculation unit 23-2 calculates the deviation Er2 between the correction set value SP2x and the control amount PV2 in the same manner as the deviation Er2 calculation unit 3-2 (step S313).

Next, similarly to the PID calculation unit 4-2, the PID calculation unit 24-2 calculates the operation amount MV2 by the PID control calculation using the deviation Er2 calculated by the deviation Er2 calculation unit 23-2 as an input, and further performs an operation. The upper and lower limit processing of the amount MV2 is executed (step S314).
The manipulated variable MV2 output unit 25-2 outputs the manipulated variable MV2 output from the PID calculating unit 24-2 to a control actuator (not shown) of the second control loop (step S315).

When the absolute value of the deviation Er2 calculated by the deviation Er2 calculation unit 23-2 is smaller than a specific value (dead zone R2), the dead zone processing unit 28-2 outputs the deviation Er2 output to the upper / lower limit processing unit 29-2. Set to 0 (step S316). Specifically, the dead zone processing unit 28-2 executes the following expression.
IF | Er2 | <R2 THEN Er2 = 0
ELSEIF Er2> 0 THEN Er2 ← Er2-R2
ELSEIF Er2 <0 THEN Er2 ← Er2 + R2 (12)

The upper / lower limit processing unit 29-2 sets Er2 = H2 when the deviation Er2 output from the dead zone processing unit 28-2 is larger than a preset upper limit value H2, and sets the deviation Er2 output from the dead zone processing unit 28-2. Is smaller than the preset lower limit value L2, deviation upper and lower limit processing is executed to set Er2 = L2 (step S317). That is, the upper / lower limit processing unit 29-2 executes the following expression.
IF Er2> H2 THEN Er2 = H2 (13)
IF Er2 <L2 THEN Er2 = L2 (14)

The operation amount MV2 saturation determination unit 30-2 determines whether or not the operation amount MV2 has reached the upper limit value OH2 or the lower limit value OL2, and sends the determination result to the magnification A2 calculation unit 26-2 (step S318).
When it is determined that the manipulated variable MV2 has reached the upper limit value OH2 or the lower limit value OL2, the magnification A2 calculation unit 26-2 has a magnification set in advance to the deviation Er2 output from the upper / lower limit processing unit 29-2. Multiply A2 and output the multiplication result A2Er2. If it is determined that the manipulated variable MV2 has not reached either the upper limit value OH2 or the lower limit value OL2, the multiplication result A2Er2 is set to 0 (step S319). . A value in the range of 0 <A2 <1 is usually used as the value of the magnification A2. Needless to say, the process of setting the multiplication result A2Er2 to 0 is a process corresponding to A2 = 0.

On the other hand, the set value SP3, which is the required value of the state quantity of the third control loop, is set by the operator and input to the adder 27-3 via the set value SP3 input unit 21-3 (step S320).
The control amount PV3, which is a measurement value of the state amount of the third control loop, is measured by a third measuring unit (not shown) and is input to the deviation Er3 calculation unit 23-3 via the control amount PV3 input unit 22-3. (Step S321).

The adder 27-3 adds the multiplication result A2Er2 of the magnification A2 calculator 26-2 to the set value SP3 to calculate the corrected set value SP3x as shown in the following equation (step S322).
SP3x = SP3 + A2Er2 (15)
The deviation Er3 calculation unit 23-3 calculates the deviation Er3 between the correction set value SP3x and the control amount PV3 by the following equation (step S323).
Er3 = SP3x-PV3 (16)

Next, the PID calculation unit 24-3 calculates the manipulated variable MV3 by performing a PID control calculation like the following transfer function equation using the deviation Er3 calculated by the deviation Er3 calculation unit 23-3 as an input (step S3). S324).
MV3 = (100 / Pb3) {1+ (1 / Ti3s) + Td3s} Er3
... (17)
In Expression (17), Pb3 is a proportional band, Ti3 is an integration time, and Td3 is a differentiation time. Note that, when the calculated operation amount MV3 is smaller than the preset output lower limit value OL3, the PID calculation unit 24-3 sets the operation amount MV3 = OL3, and the calculated operation amount MV3 is greater than the preset output upper limit value OH3. If larger, an operation amount upper / lower limit process is performed with the operation amount MV3 = OH3.

  The manipulated variable MV3 output unit 25-3 outputs the manipulated variable MV3 output from the PID calculating unit 24-3 to a control actuator (not shown) of the third control loop (step S325). The control actuator operates to control the state quantity of the third control loop based on the operation quantity MV3.

When the absolute value of the deviation Er3 calculated by the deviation Er3 calculation unit 23-3 is smaller than a specific value (dead zone R3), the dead zone processing unit 28-3 outputs the deviation Er3 output to the upper / lower limit processing unit 29-3. It is set to 0 (step S326). Specifically, the dead zone processing unit 28-3 executes the following expression.
IF | Er3 | <R3 THEN Er3 = 0
ELSEIF Er3> 0 THEN Er3 ← Er3-R3
ELSEIF Er3 <0 THEN Er3 ← Er3 + R3 (18)

The upper / lower limit processing unit 29-3 sets Er3 = H3 when the deviation Er3 output from the dead zone processing unit 28-3 is larger than a preset upper limit value H3, and the deviation Er3 output from the dead zone processing unit 28-3. Is smaller than the preset lower limit value L3, deviation upper / lower limit processing is performed to set Er3 = L3 (step S327). That is, the upper / lower limit processing unit 29-3 executes the following expression.
IF Er3> H3 THEN Er3 = H3 (19)
IF Er3 <L3 THEN Er3 = L3 (20)

The operation amount MV3 saturation determination unit 30-3 determines whether or not the operation amount MV3 has reached the upper limit value OH3 or the lower limit value OL3, and sends the determination result to the magnification A3 calculation unit 26-3 (step S328).
When it is determined that the manipulated variable MV3 has reached the upper limit value OH3 or the lower limit value OL3, the magnification A3 calculating unit 26-3 sets the magnification set in advance to the deviation Er3 output from the upper / lower limit processing unit 29-3. Multiply A3 and output the multiplication result A3Er3. If it is determined that the manipulated variable MV3 has not reached either the upper limit value OH3 or the lower limit value OL3, the multiplication result A3Er3 is set to 0 (step S329). . As the value of the magnification A3, a value in the range of 0 <A3 <1 is usually used. Needless to say, the process of setting the multiplication result A3Er3 to 0 is a process corresponding to A3 = 0.

  The processes in steps S300 to S329 as described above are repeatedly executed for each control cycle until the operator instructs the end of the control (YES in step S330).

  In the present embodiment, the deviations Er1, Er2, and Er3 are multiplied by the magnifications A1, A2, and A3, respectively, and the multiplication results A2Er2 are added to the set values SP1 and SP3 to correct the set values SP1 and SP3. By correcting the setting value SP2 by adding the results A1Er1 and A3Er3 to the setting value SP2, the deviation of the operation amount MV2 of the second control loop based on the correction setting value SP2x is a steady deviation of the first and third control loops. This affects the direction in which Er1 and Er3 are reduced, and the deviation of the operation amounts MV1 and MV3 of the first and third control loops based on the correction setting values SP1x and SP3x reduces the steady-state deviation Er2 of the second control loop. Since the direction is affected, it is possible to realize a cooperative operation for reducing the absolute values of the steady-state errors Er1, Er2, Er3.

  In the present embodiment, the magnification calculators 26-1 to 26-3 set the operation amounts MV1, MV2, and MV3 to the upper and lower limit values according to the determination results of the operation amount saturation determination units 30-1 to 30-3. If it has reached, the deviations Er1, Er2, Er3 are multiplied by the magnifications A1, A2, A3 (cooperation between multi-loops is on), and if the manipulated variables MV1, MV2, MV3 have not reached the upper and lower limit values, the multiplication result Since 0 is set to 0 (cooperative operation off), the operation of the control device can be appropriately switched according to the state of the operation amounts MV1, MV2, and MV3. Further, in the present embodiment, by providing the dead zone processing units 28-1 to 28-3, when the steady deviation is very small, the steady deviation can be ignored and the cooperative operation between the multi-loops can be turned off. it can. In the present embodiment, the upper and lower limit processing units 29-1 to 29-3 are provided so that the correction set value SPx does not deviate significantly from the original set value SP when the steady-state deviation is extremely large. can do. In this way, in this embodiment, a practically suitable additional function can be realized.

  In the second and third embodiments, the multiplication result of one control cycle before the magnification calculation unit of another control loop is used in some of the addition units. However, when calculating the correction set value, If the multiplication result of the magnification calculation unit of another control loop has already been calculated in the same control cycle, the multiplication result may be used. If the multiplication result has not yet been calculated, the multiplication result one control cycle before Can be used.

[Fourth Embodiment]
In the first to third embodiments, the deviation Er = SPx-PV at the stage used for the PID calculation is processed to correct the set value SP of the adjacent control loop, but a commercially available temperature controller In such a case, as shown by the broken line in FIG. 11, the deviation calculating units 23-1, 23-2, 23-3 and the PID calculating units 24-1, 24-2, 24-3 are inside the temperature controller. It is difficult to take out the deviations Er1, Er2, Er3 outside the temperature controller. In this case, the deviations Er1, Er2, and Er3 must be calculated separately, but in order to obtain the effects of the present invention, there is no problem even if the deviation Er ′ = SP−PV is simply substituted.

  FIG. 11 is a block diagram of a state quantity control system in which deviations Er1 ′, Er2 ′, and Er3 ′ are used instead of deviations Er1, Er2, and Er3. Deviation Er1 between set value SP1 and control quantity PV1 '= SP1-PV1 is calculated by the deviation calculating unit 31-1, and the deviation Er1' is input to the dead zone processing unit 28-1 instead of the deviation Er1, and the deviation Er2 'between the set value SP2 and the control amount PV2' = SP2 -PV2 is calculated by the deviation calculating unit 31-2, and the deviation Er2 'is input to the dead zone processing unit 28-2 instead of the deviation Er2, and the deviation Er3' = SP3-PV3 between the set value SP3 and the control amount PV3 is The deviation calculation unit 31-3 calculates the deviation Er3 ′ instead of the deviation Er3, and inputs the deviation Er3 ′ to the dead zone processing unit 28-3. The configuration as the state quantity control device is the third embodiment except that the deviations Er1 ′, Er2 ′, Er3 ′ are used instead of the deviations Er1, Er2, Er3 to correct the set values SP1, SP2, SP3. It is the same as the form. The state quantity control device described in the first to fourth embodiments can be realized by a computer including an arithmetic device, a storage device, and an interface, and a program for controlling these hardware resources.

  The present invention can be applied to multi-loop state quantity control.

It is a figure for demonstrating the effect of the state quantity control apparatus of this invention. It is a block diagram which shows the structure of the state quantity control apparatus used as the 1st Embodiment of this invention. It is a flowchart which shows operation | movement of the state quantity control apparatus of FIG. It is a block diagram of the multi-loop state quantity control system in the 1st Embodiment of this invention. It is a block diagram which shows the structure of the state quantity control apparatus used as the 2nd Embodiment of this invention. It is a flowchart which shows operation | movement of the state quantity control apparatus of FIG. It is a block diagram of the multi-loop state quantity control system in the 2nd Embodiment of this invention. It is a block diagram which shows the structure of the state quantity control apparatus used as the 3rd Embodiment of this invention. It is a flowchart which shows operation | movement of the state quantity control apparatus of FIG. It is a block diagram of the multi-loop state quantity control system in the 3rd Embodiment of this invention. It is a block diagram of the multi-loop state quantity control system in the 4th Embodiment of this invention. It is a block diagram which shows the structure of the conventional multiloop temperature control system. It is a figure which shows the setting value of each control loop, control amount, and operation amount when the steady deviation has generate | occur | produced in the specific control loop in the multi-loop temperature control system of FIG.

Explanation of symbols

  3-1, 3-2, 13-1, 13-2, 23-1, 23-2, 23-3 ... Deviation calculation unit, 4-1, 4-2, 14-1, 14-2, 24- 1, 24-2, 24-3 ... PID operation unit, 6-1, 16-1, 16-2, 26-1, 26-2, 26-3 ... magnification operation unit, 7-2, 17-1, 17-2, 27-1, 27-2, 27-3 ... addition unit, 28-1, 28-2, 28-3 ... dead zone processing unit, 29-1, 29-2, 29-3 ... upper / lower limit processing Unit, 30-1, 30-2, 30-3, operation amount saturation determination unit.

Claims (8)

In a control device of a multi-loop control system provided with a plurality of control loops that respectively control a plurality of controlled objects that have a relationship of interfering with each other's control amount,
A magnification calculator that multiplies the deviation of a specific control loop in which a deviation occurs between a set value and a control amount by a preset magnification;
A control apparatus comprising: an addition unit that adds a multiplication result of the magnification calculation unit to a set value of another control loop in which the interference exists with the specific control loop. In a control device of a multi-loop control system provided with a plurality of control loops that respectively control a plurality of controlled objects that have a relationship of interfering with each other's control amount,
A first deviation calculating unit for calculating a deviation between the set value and the controlled variable for a specific control loop;
A first control calculation unit that calculates an operation amount using a deviation of the specific control loop as an input and outputs the operation amount to a control target of the specific control loop;
A magnification calculator for multiplying a deviation of the specific control loop by a preset magnification;
An adder that is provided in another control loop in which the interference exists with the specific control loop, and that adds a multiplication result of the magnification calculator to a setting value of the corresponding control loop to calculate a correction setting value; ,
A second deviation calculating unit for calculating a deviation between the correction set value and the control amount for the other control loop;
A control device comprising: a second control calculation unit that calculates an operation amount using a deviation of the other control loop as an input and outputs the operation amount to a control target of the other control loop. In a control device of a multi-loop control system provided with a plurality of control loops that respectively control a plurality of controlled objects that have a relationship of interfering with each other's control amount,
A deviation calculating unit for calculating a deviation between the correction set value obtained by correcting the set value for each control loop and the control amount;
A control operation unit that calculates an operation amount using the deviation as an input for each control loop and outputs it to a control target of a corresponding control loop; and
A magnification calculator for multiplying the deviation by a preset magnification for each control loop;
An addition unit that calculates the correction setting value by adding the multiplication result of another control loop in which the interference exists with the control loop to the setting value for each control loop. Control device. The control device according to any one of claims 1 to 3,
Furthermore, when receiving and outputting the deviation for each control loop, if the absolute value of the deviation is smaller than a specific value, a dead zone processing unit that sets the deviation to 0,
Upper and lower limit processing units for performing upper and lower limit processing for limiting the deviation output from the dead zone processing unit for each control loop within a preset upper limit value and lower limit value;
An operation amount saturation determination unit that determines whether or not the operation amount has reached an upper and lower limit value for each control loop, and notifies the determination result to the magnification calculation unit of the corresponding control loop,
When it is determined that the operation amount of the corresponding control loop has reached the upper and lower limit values, the magnification calculation unit multiplies the deviation subjected to the upper and lower limit processing of the corresponding control loop by a preset magnification. A control result, and when it is determined that the manipulated variable of the corresponding control loop has not reached the upper and lower limit values, the control result is set to 0. In a control method of a multi-loop control system including a plurality of control loops that respectively control a plurality of control objects that interfere with each other's control amount,
A magnification calculation procedure for multiplying the deviation of a specific control loop in which a deviation occurs between a set value and a control amount by a preset magnification,
A control method comprising: an addition procedure for adding a multiplication result of the magnification calculation procedure to a set value of another control loop in which the interference exists with the specific control loop. In a control method of a multi-loop control system including a plurality of control loops that respectively control a plurality of control objects that interfere with each other's control amount,
A first deviation calculating procedure for calculating a deviation between the set value and the controlled variable for a specific control loop;
A first control calculation procedure for calculating an operation amount using a deviation of the specific control loop as an input and outputting the operation amount to a control target of the specific control loop;
A magnification calculation procedure for multiplying a deviation of the specific control loop by a preset magnification,
An addition procedure for calculating a correction setting value by adding the multiplication result of the magnification calculation procedure to a setting value of another control loop in which the interference exists with the specific control loop;
A second deviation calculating procedure for calculating a deviation between the correction set value and the controlled variable for the other control loop;
A control method comprising: repeatedly executing a control calculation procedure for calculating an operation amount using a deviation of the other control loop as an input and outputting the operation amount to a control target of the other control loop. In a control method of a multi-loop control system including a plurality of control loops that respectively control a plurality of control objects that interfere with each other's control amount,
A deviation calculation procedure for calculating a deviation between the correction set value obtained by correcting the set value for each control loop and the control amount;
A control calculation procedure for calculating an operation amount using the deviation as an input for each control loop and outputting it to a control target of a corresponding control loop;
A magnification calculation procedure for multiplying the deviation by a preset magnification for each control loop;
An addition procedure for calculating the correction setting value by adding the multiplication result for another control loop in which the interference exists between the control loop and the setting value for each control loop is repeatedly executed. Control method. The control method according to any one of claims 5 to 7,
Furthermore, when receiving and outputting the deviation for each control loop, if the absolute value of the deviation is smaller than a specific value, a dead zone processing procedure for setting the deviation to 0,
Upper / lower limit processing procedure for executing upper / lower limit processing for limiting the deviation output in the dead zone processing procedure for each control loop within a range of preset upper limit value and lower limit value;
An operation amount saturation determination procedure for determining whether or not the operation amount has reached the upper and lower limit values for each control loop,
When it is determined that the operation amount of the corresponding control loop has reached the upper and lower limit values, the magnification calculation procedure multiplies the deviation subjected to the upper and lower limit processing of the corresponding control loop by a preset magnification. The multiplication result is output, and if it is determined that the manipulated variable of the corresponding control loop has not reached the upper and lower limit values, the multiplication result is set to 0.

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