Indicated value derivation device, program, indicated value derivation method, and apparatus production method

Abstract

To simply derive a second indicated value when a first indicated value is a specific value.SOLUTION: An indicated value derivation device 10 comprises an acquisition unit 31S which acquires a combination of an operation amount MV1, a main indicated value PVm1, and a sub-indicated value PVs1, and a combination of an operation amount MV2, a main indicated value PVm2, and a sub-indicated value PVs2 when the main indicated value (PVm) and the sub-indicated value (PVs), which are correlated with each other through a feedback control, are stabilized. A first derivation unit 31T derives an increase amount in a main indicated value ΔPVm, and an increase amount in a sub-indicated value ΔPVs, per unit operation amount based on the acquired combinations. A second derivation unit 31U derives an operation amount MVs(SP) when the main indicated value is a target indicated value SPm, based on the increase amount ΔPVm. A third derivation unit 31V derives a sub-indicated value ΔPVs(SP) when the main indicated value is a target indicated value SPm, based on the increase amount ΔPVs and the operation amount MVs(SP).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a technique for deriving an instruction value in feedback control. [Background technology]

[0002] In feedback control, a plurality of kinds of command values ​​that change in conjunction with each other are used. For example, in cascade control, a main command value and a sub command value are used (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-017187 A Summary of the Invention [Problem to be solved by the invention]

[0004] In certain cases, such as initial setting of cascade control, it may be desirable to simply derive a second instruction value (e.g., a secondary instruction value) when a first instruction value (e.g., a main instruction value) is a specific value (e.g., a target instruction value).

[0005] The present invention has been made in consideration of the above-mentioned points, and an object of the present invention is to simply derive a second instruction value when a first instruction value is a specific value. [Means for solving the problem]

[0006] In order to solve the above problem, the instruction value derivation device of the present invention includes an acquisition unit that acquires multiple combinations including an operation amount, a first instruction value, and a second instruction value when a first instruction value and a second instruction value that are correlated with each other by feedback control become stable, a first derivation unit that derives an increase in the first instruction value and an increase in the second instruction value per unit operation amount based on the acquired multiple combinations, a second derivation unit that derives an operation amount when the first instruction value is a specific value based on the derived increase in the first instruction value, and a third derivation unit that derives the second instruction value when the first instruction value is the specific value based on the derived increase in the second instruction value and the derived operation amount.

[0007] The second derivation unit may derive the manipulated variable based on the increase amount of the first instruction value and the manipulated variable and the first instruction value of one combination of the plurality of combinations.

[0008] The third derivation unit may derive the operation amount based on the increase amount of the second instruction value and the operation amount when the second instruction value is the specific value, and the operation amount and the second instruction value of one combination among the multiple combinations.

[0009] The feedback control may be a cascade control, the first instruction value being a primary instruction value, the second instruction value being a secondary instruction value, and the specific value being a target instruction value.

[0010] The instruction value derivation device may further include a fourth derivation unit that derives a parameter for the feedback control based on the derived second instruction value, and performs initial setting of a device that performs the feedback control based on the derived parameter.

[0011] A program according to the present invention causes a computer to function as the indicated value deriving device.

[0012] The method for deriving an indication value according to the present invention includes a first step of deriving an increase amount of the first indication value and an increase amount of the second indication value per unit operation amount based on a plurality of combinations including an operation amount, a first indication value, and a second indication value when a first indication value and a second indication value that are correlated with each other by feedback control become stable; a second step of deriving an operation amount when the first indication value is a specific value based on the derived increase amount of the first indication value; and a third step of deriving the second indication value when the first indication value is the specific value based on the derived increase amount of the second indication value and the derived operation amount.

[0013] The above-mentioned indication value derivation method may further include a step of obtaining the first indication values ​​and the second indication values ​​of the multiple combinations by measurement after an apparatus that is a target of the feedback control is installed at an operating location of the apparatus.

[0014] The method of producing a device according to the present invention includes a command value deriving method, and a step of initializing a device that performs the feedback control based on the second command value derived by the command value deriving method. Effect of the Invention

[0015] According to the present invention, the second indication value is derived simply and easily when the first indication value is a specific value. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a block diagram showing a configuration of an indication value derivation device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a block diagram showing the configuration of an indication value deriving device serving as a temperature regulator according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a block diagram showing a configuration of an indication value derivation device according to an embodiment of the present invention. [Figure 4] FIG. 4 is a flow chart of the derivation process performed in an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0018] The instruction value derivation device 10 according to this embodiment shown in FIG. 1 is configured as a temperature regulator that performs cascade control with the temperature of air 92 that heats the workpiece W in a container 91 as a primary control object and the temperature of a heat medium 93 that heats the air 92 from the outside of the container 91 as a secondary control object. As a characteristic function of this embodiment, the instruction value derivation device 10 also has a function of deriving a measured instruction value for the temperature of the heat medium 93 when the measured instruction value that measures the temperature of the air 92 is a desired target instruction value. The derived measured instruction value is used during initial setting of the cascade control. Below, the functions related to the cascade control will be explained first, and then the characteristic functions of this embodiment will be explained.

[0019] The indication value derivation device 10 includes a measurement circuit 21m that measures the temperature of the air 92 (primary controlled object) using a temperature sensor Sm and outputs the measured temperature as a primary indication value PVm, and a measurement circuit 21s that measures the temperature of the heat medium 93 (secondary controlled object) using a temperature sensor Ss and outputs the measured temperature as a secondary indication value PVs.

[0020] The indication value derivation device 10 includes a control device 30 that performs cascade control based on the indication values ​​PVm, PVs output by the measurement circuits 21m and 21s, and an operating end 41 that outputs an operating amount MVs1 based on the cascade control to a heating device 99 that heats a heat medium 93.

[0021] The control device 30 is configured with a computer, etc. The control device 30 includes a processor 31 such as a CPU, a RAM 32 that functions as a main memory for the processor 31, and a non-volatile storage 33 that stores programs and data executed or used by the processor 31.

[0022] The processor 31 executes a program stored in the storage 33 to function as a first control unit 31A and a second control unit 31B shown in FIG.

[0023] It is assumed that a target instruction value SPm for the temperature of the air 92, which is the main control target (i.e., a desired temperature to which the workpiece W is to be heated), is set in the first control unit 31A. The target instruction value SPm is set from outside the instruction value derivation device 10 via an input / output unit (not shown).

[0024] A primary instruction value PVm (measured temperature of the air 92) from the measurement circuit 21m is input as a controlled variable to the first control unit 31A. The first control unit 31A derives a manipulated variable MVm, which is indicated by a value from 0 to 100%, based on the target instruction value SPm and the primary instruction value PVm.

[0025] The second control unit 31B receives a secondary instruction value PVs (measured temperature of the heat medium 93) from the measurement circuit 21s as a controlled variable. The second control unit 31B converts the manipulated variable MVm (%) into a target value SPs (°C) and derives a manipulated variable MVs0 based on the target value SPs and the secondary instruction value PVs. The second control unit 31B outputs the derived manipulated variable MVs0 to the heating device 99 in the form of a current signal or the like via the manipulated terminal 41. The manipulated terminal 41 converts the manipulated variable MVs0, which is expressed as a value between 0 and 100%, into a manipulated variable MVs1, which is expressed as a current value or the like, and outputs it to the heating device 99.

[0026] The above processes are executed at predetermined intervals to realize cascade control.

[0027] In the initial setting for the above-mentioned cascade control, a conversion formula is set to convert the manipulated variable MVm into the target value SPs. Any conversion formula may be used, but for example, the following formula (1) is used. Here, SH is the upper limit of scaling, and SL is the lower limit of scaling. SPs=(MVm÷100)×(SH-SL)+SL...Equation (1)

[0028] The values ​​of SH and SL are determined based on the secondary instruction value PVs when the primary instruction value PVm is stabilized at the target instruction value SPm. For example, SH and SL are determined with the secondary instruction value PVs as the median. Therefore, the derivation of the secondary instruction value PVs is very important for accurate cascade control. As a comparative example, the secondary instruction value PVs that is the basis of the values ​​of SH and SL is specified by the following method. (1) First, control only the secondary controlled object in single control to stabilize the secondary indication value PVs at a given temperature, and then wait until the primary indication value PVm stabilizes. (2) The above (1) is repeated by changing the arbitrary temperature, and the stabilized primary indication value PVm is adjusted to match the target indication value SPm, and the secondary indication value PVs at that time is identified as the secondary indication value PVs on which the values ​​of SH and SL are based.

[0029] However, the above method has the following problems. (A) The controlled object of cascade control often has a long response time, so it takes time for the primary indication value PVm to stabilize. For example, even if the secondary indication value PVs stabilizes in 15 minutes, the primary indication value PVm may not stabilize until one hour has passed. (B) The relationship between the primary indication value PVm and the secondary indication value PVs is generally unknown, and the above-mentioned arbitrary temperature must be determined appropriately, which results in a large number of repetitions of the above (1). As can be seen from (A) and (B) above, in the conventional method, it takes time and effort to identify the secondary indication value PVs that is the basis of the values ​​of SH and SL.

[0030] In order to reduce the time and effort required to identify the secondary indication value PVs that is the basis of the values ​​of SH and SL, the processor 31 of the control device 30 operates as a monitoring unit 31R, an acquisition unit 31S, a first derivation unit 31T, a second derivation unit 31U, a third derivation unit 31V, and a fourth derivation unit 31W shown in FIG. 3 by executing a program in the storage 33. The units 31R to 31V cooperate to perform the process shown in FIG. 4. The derivation process shown in FIG. 4 is performed at any timing when the device to be controlled by the cascade control (i.e., the device including the container 91, the heat medium 93, and the heating device 99) is installed at the operating location and before the cascade control is started. The arbitrary timing is, for example, when an instruction to that effect is input by an operator to the indication value derivation device 10 via an operation device (not shown) or the like.

[0031] In the derivation process of Figure 4, first, the monitoring unit 31R inputs the operation amount MV1, which is an arbitrary operation amount MVs2, to the heating device 99 via the operating end 41 (step S11), and then monitors the primary indication value PVm and the secondary indication value PVs from the measurement circuits 21m and 21s, and determines whether these values ​​are stable (step S12).

[0032] The manipulated variable MV1 may be set in advance together with the manipulated variable MV2 described later, or may be determined by an operator who performs the initial setting of the cascade control and input to the command value derivation device 10 via an operation device (not shown) or the like. Here, as will be understood from the following explanation, the sub command value PVs on which the values ​​of SH and SL are based is derived based on the fact that the manipulated variable and the controlled variable, i.e., the command value, are in a proportional relationship, and therefore the manipulated variables MV1 and MV2 are preferably selected from a numerical range in which the manipulated variable and the controlled variable, i.e., the command value, are in a proportional relationship.

[0033] In step S11, for example, when each of the primary indication value PVm and the secondary indication value PVs or each of their derivative values ​​falls within a predetermined range for a predetermined period, the primary indication value PVm and the secondary indication value PVs are determined to be stable. The predetermined range may be different for the primary indication value PVm and the secondary indication value PVs. When it is determined to be stable (step S12: Yes), the monitoring unit 31R records the stable primary indication value PVm and secondary indication value PVs as the primary indication value PVm1 and the secondary indication value PVs1 in the storage 33 together with the manipulated variable MV1 (step S13).

[0034] Thereafter, the monitoring unit 31R performs the same processes as in steps S11 to S13 (steps S14 to S16). However, the manipulated variable MV1 is changed to the manipulated variable MV2. Furthermore, the primary instruction value PVm and the secondary instruction value PVs that are stable at the manipulated variable MV2 are recorded as the primary instruction value PVm2 and the secondary instruction value PVs2. As a result, the manipulated variable MV2 and the primary instruction value PVm2 and the secondary instruction value PVs2 that are stable at the manipulated variable MV2 are recorded in the storage 33.

[0035] Thereafter, the acquisition unit 31S acquires a first combination of the manipulated variable MV1, the primary indicator value PVm1, and the secondary indicator value PVs1, and a second combination of the manipulated variable MV2, the primary indicator value PVm2, and the secondary indicator value PVs2 from the storage 33 (step S17). The acquisition unit 31S appropriately supplies the acquired various information to the derivation units 31T to 31W.

[0036] Thereafter, the first derivation unit 31T derives the respective increase amounts ΔPVm and ΔPVs of the primary indicator value PVm and the secondary indicator value PVs per unit operation amount based on the first combination and the second combination acquired by the acquisition unit 31S (step S18). ΔPVm is expressed, for example, by the following formula (2). ΔPVs is expressed, for example, by the following formula (3). ΔPVm=(PVm1-PVm2) / (MV1-MV2)...Equation (2) ΔPVs=(PVs1-PVs2) / (MV1-MV2)...Equation (3)

[0037] Thereafter, the second derivation unit 31U derives the manipulated variable MVs(SP) when the primary instruction value PVm is the target instruction value SPm based on the increase ΔPVm (step S19). The manipulated variable MVs(SP) is expressed by the following formula (5) or formula (6). MVs(SP)=MV1+(SPm-PVm1) / ΔPVm...Equation (4) MVs(SP)=MV2+(SPm-PVm2) / ΔPVm...Equation (5)

[0038] Thereafter, the third derivation unit 31V derives the secondary instruction value PVs(SP) when the primary instruction value PVm is the target instruction value SPm based on the manipulated variable MVs(SP) and the increment ΔPVs (step S20). The secondary instruction value PVs(SP) is expressed by the following formula (6) or formula (7). PVs(SP)=PVs1+ΔPVs×(MVs(SP)-MV1)...Equation (6) PVs(SP)=PVs2+ΔPVs×(MVs(SP)-MV2)...Equation (7)

[0039] Thereafter, the fourth derivation unit 31W derives parameters for cascade control (e.g., the above-mentioned SL and SH) based on the secondary command value PVs (SP), and performs initial setting of the control device 30 based on the derived parameters (step S21). Formulas for deriving parameters, etc. are set arbitrarily. Such initial setting of the device 10 performing cascade control based on the secondary command value PVs (SP) enables the device 10 to execute cascade control. This can also be said to have produced the control device 30 performing cascade control. The derivation and initial setting of the parameters may be performed manually.

[0040] When the primary instruction value PVm1=the target instruction value SPm, the secondary instruction value PVs(SP)=the secondary instruction value PVs1, or when the primary instruction value PVm2=the target instruction value SPm, the secondary instruction value PVs(SP)=the secondary instruction value PVs2. In such cases, steps S18 to S20 may be skipped.

[0041] Here, a specific example of the derivation of the secondary command value PVs(SP) will be described. Note that, here, the target command value SPm=100° C. (a) When MV1 = 20%, PVm1 = 50°C and PVs1 = 80°C. (b) When MV2 = 80%, PVm2 = 150°C and PVs2 = 200°C and stabilized. (c) The increase ΔPVm in the primary indication value PVm per 1% of the control volume MVs is (50℃-150℃) / (20%-80%) ≒ 1.67℃. (d) The increase ΔPVs in the secondary indication value PVs per 1% of the manipulated variable MVs is (80℃−200℃) / (20%−80%)=2℃. (e) Based on the above (c) and (a), the manipulated variable MVs(SP) for the primary command value PVm=100°C (target command value SPm) is 20%+(100°C-50°C)÷1.67°C=49.9%. Note that the value in (b) may be used instead of (a). (f) Based on the above (d), (e), and (a), when the primary indication value PVm = 100°C (target indication value SPm), the secondary indication value PVs (SP) = 80°C + 2°C × (49.9°C - 20°C) = 139.8°C. Note that the value of (b) may be used instead of (a).

[0042] As described above, in this embodiment, the secondary command value PVs (SP) when the primary command value PVm is stabilized at the target command value SPm is automatically derived from a small number (here, two) of manipulated variables MVs. On the other hand, in the comparative example, the number of repetitions of the above (1) is usually not only two, but many times are required. Therefore, in this embodiment, the time and effort required to derive the secondary command value PVs (SP) is reduced. In other words, the secondary command value PVs (SP) is derived easily.

[0043] Note that the relationship between the primary indication value PVm and the secondary indication value PVs may differ even if the controlled object is an apparatus of the same design due to positional deviation or individual difference of the sensor, differences in operating environment, etc. In this embodiment, the indication values ​​PVm1, PVm2, PVs1, and PVs2 required to derive the secondary indication value PVs (SP) are obtained by measurement after the controlled object of the cascade control (i.e., the apparatus including the container 91, the heat medium 93, and the heating device 99) is installed at the operating location of the apparatus, so that the effects of positional deviation or individual difference of the sensor, differences in operating environment, etc. are suppressed, and a highly accurate secondary indication value PVs (SP) is derived.

[0044] The hardware configuration of the indication value derivation device 10 is arbitrary. At least a part of the above-mentioned units 31R to 31W may be configured by a dedicated processor such as ASIC or FPGA, which is not a general-purpose processor. Furthermore, the units 31R to 31W may be provided in a server device capable of communicating with the temperature regulator. In such a case, the server device operates as the indication value derivation device 10.

[0045] The present invention is not limited to cascade control, but is applicable to feedback control in general. That is, the instruction value derivation device may include an acquisition unit that acquires a plurality of combinations including an operation amount, a first instruction value, and a second instruction value when the first instruction value and the second instruction value that are mutually correlated in feedback control are stable, a first derivation unit that derives an increase amount of the first instruction value and an increase amount of the second instruction value per unit operation amount based on the acquired plurality of combinations, a second derivation unit that derives an operation amount when the first instruction value is a specific value based on the derived increase amount of the first instruction value, and a third derivation unit that derives the second instruction value when the first instruction value is the specific value based on the derived increase amount of the second instruction value and the derived operation amount. The first instruction value and the second instruction value may be instruction values ​​of physical quantities with different units. For example, the main instruction value may be temperature, and the secondary instruction value may be the flow rate (valve opening) of a refrigerant, etc.

[0046] In addition, when the right side of the above formula (2) is substituted into the above formula (4) or (5) to perform calculations, or when the right side of the above formula (3) is substituted into the above formula (6) or (7) to perform calculations, it may seem at first glance that the "increase in the first indication value and the increment in the second indication value per unit operation amount" has not been derived, but the significance of each calculation after the expansion is the same as that of obtaining each of the increments. Therefore, the calculation after the expansion is also included in the derivation of the "operation amount when the first indication value is a specific value" and the "second indication value when the first indication value is the specific value" by the first to third derivation units via the "increase in the first indication value and the increment in the second indication value per unit operation amount" as described above. In addition, each of the above derivations includes, in addition to calculations, obtaining a desired value by referring to a table.

[0047] Although the present invention has been described above with reference to the embodiments and modifications, the present invention is not limited to the above embodiments and modifications. For example, the present invention includes various modifications to the above embodiments and modifications that can be understood by a person skilled in the art within the scope of the technical concept of the present invention. The configurations listed in the above embodiments and modifications can be appropriately combined within a range without contradiction. Also, the omission of each configuration is optional. [Explanation of symbols]

[0048] 10...indication value derivation device, 21m...measurement circuit, 21s...measurement circuit, 30...control device, 31...processor, 31A...first control unit, 31B...second control unit, 31R...monitoring unit, 31S...acquisition unit, 31T...first derivation unit, 31U...second derivation unit, 31V...third derivation unit, 31W...fourth derivation unit, 33...storage, 41...operation end, 91...container, 92...air, 93...heat medium, 99...heating device, MV1...operated amount, MV2...operated amount, MVm...operated amount, MVs, MVs0, MVs1, MVs2...operated amount, PVm...primary indication value, PVm1...primary indication value, PVm2...primary indication value, PVs...secondary indication value, PVs1...secondary indication value, PVs2...secondary indication value, Sm...temperature sensor, SPm...target indication value, SPs...target value, Ss...temperature sensor, W...work, ΔPVm...increase, ΔPVs...increase.

Claims

1. an acquisition unit that acquires a plurality of combinations including an operation amount, a first instruction value, and a second instruction value when the first instruction value and the second instruction value that are correlated with each other through feedback control are stabilized; a first derivation unit that derives an increase amount of the first indication value and an increase amount of the second indication value per unit operation amount based on the acquired multiple combinations; a second derivation unit that derives an operation amount when the first instruction value is a specific value based on the derived increase amount of the first instruction value; a third derivation unit that derives the second instruction value when the first instruction value is the specific value, based on the derived increase amount of the second instruction value and the derived operation amount; An indication value deriving device comprising:

2. The second derivation unit derives the operation amount based on the increase amount of the first instruction value and the operation amount and the first instruction value of one combination of the plurality of combinations. The indication value deriving device according to claim 1 .

3. the third derivation unit derives the operation amount based on the increase amount of the second instruction value and the operation amount when the second instruction value is the specific value, and the operation amount and the second instruction value of one combination among the multiple combinations. The indication value deriving device according to claim 1 .

4. The feedback control is a cascade control. The first indication value is a primary indication value, The second indication value is a sub indication value, The specific value is a target indication value. The indication value deriving device according to claim 1 .

5. A fourth derivation unit derives a parameter of the feedback control based on the derived second instruction value, and performs an initial setting of the device that performs the feedback control based on the derived parameter. The indication value deriving device according to claim 1 .

6. A program causing a computer to function as the indicated value deriving device according to any one of claims 1 to 4.

7. a first step of deriving an increase amount of the first instruction value and an increase amount of the second instruction value per unit manipulated variable based on a plurality of combinations including an manipulated variable, a first instruction value, and a second instruction value when the first instruction value and the second instruction value, which are correlated with each other by feedback control, are stabilized; a second step of deriving an operation amount when the first instruction value is a specific value, based on the derived increase amount of the first instruction value; a third step of deriving the second instruction value when the first instruction value is the specific value, based on the derived increase amount of the second instruction value and the derived operation amount; The indication value deriving method includes the steps of:

8. The method further includes a step of obtaining the first indication value and the second indication value of the plurality of combinations by measurement after the feedback-controlled target device is installed at an operating location of the device. The method for deriving an indication value according to claim 7.

9. The indication value deriving method according to claim 7 or 8, performing an initial setting of a device that performs the feedback control based on the second instruction value derived by the instruction value derivation method; A method for producing an apparatus comprising:

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