JP2005078463A - Measurement control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To organize a whole system from preparation for motion models of a controlled object to construction for a control system of the controlled object in sequence. <P>SOLUTION: A measurement control system 1 has the theoretical action model for the controlled object 3, a model preparation portion 20 preparing the controlled action model, a measuring portion 11 obtaining effective factors for the controlled object 3 as input signals and outputting control signals to the controlled object 3 in proportion to the input signals, a simulation portion 25 executing simulated experiments of the theoretical action model, and a control portion 16 controlling the measuring portion 11. The theoretical action model shows a physical and chemical phenomenon generated on the controlled object 3 with an expression, and is determined by permutating discrete arithmetic processings included in the expression with discrete model components. The controlled action model can be determined from the results of simulated experiments of the theoretical action model so as to satisfy equivalent relationship or the like with the theoretical action model at a designated level, and functions of the measuring portion 11 can be determined by permutating with control actions of the control portion 16. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a measurement control system, and more particularly to a measurement control system that performs all of measurement, analysis, operation model creation, and control of a control target with a single unit.

  In recent years, automatic control systems have been introduced in various technical fields in order to reduce development and manufacturing costs.

  For example, in the automotive industry field, oil tanks that can be controlled over a wide range and at a constant temperature are used to analyze the friction characteristics of vehicle parts, but even a small change in oil temperature does not affect the friction characteristics of parts. Since it is large, conventionally, the oil temperature of the oil tank is kept constant by a liquid temperature control device as disclosed in Patent Document 1.

  However, the automatic control system including such a liquid temperature control device has technical problems described below.

JP 11-294927 A

  Since the liquid temperature control device disclosed in Patent Document 1 is generally customized based on the property of the control target for each control target (for example, a liquid tank), once it is incorporated into the control target. Therefore, it was difficult to combine with other control objects and to cope with specification changes.

  In the first place, in order to construct an automatic control system such as a liquid temperature control device, it is necessary to grasp the operation principle of the controlled object (for example, what causes the liquid temperature to change).

  In order to understand the operation principle of the controlled object, data that is likely to be the basis of the operation principle is collected and stored once, and the causal relationship between the data is analyzed and estimated using multivariate analysis software on a computer. There is a need.

  Based on the analysis result of the collected data, an operation model to be controlled is created, and the validity of the operation model is confirmed through simulation, experiment, etc., and then the actual automatic control system operates (actual operation).

  Although the process as described above is not considered in the invention disclosed in Patent Document 1, for example, an operation model confirmation experiment for controlling the oil temperature of the oil tank to be constant takes a long time as the oil tank becomes larger. Therefore, it took a considerable amount of time to construct the final automatic control system.

  Moreover, conventionally, the measurement device, the analysis device, and the control device necessary for the automatic control system are configured separately and independently, and the builder of the automatic control system has constructed the system by appropriately combining them. In the experimental stage and the actual operation stage, it was necessary to use different combinations of devices.

  Therefore, there is a problem that even if it operates in the experimental stage, it does not operate in the actual operating stage, and the transition from the experimental stage to the actual operating stage is troublesome, such as rearrangement of sensors connected to the measuring device and programming work for the control device. There was a problem.

The present invention has been made in view of such conventional problems, and the object of the present invention is to perform all of measurement, analysis, operation model creation, control, and development / manufacturing cost. The object is to provide a measurement control system that contributes to a significant reduction.

  In order to achieve the above object, a measurement control system of the present invention includes a model creation unit that creates a theoretical motion model and a control motion model related to a controlled object, a function that acquires an effective factor related to the controlled object as an input signal, Measurement control having a measurement unit having a function of outputting a control signal to the control target in response to an input signal, a simulation unit for performing a simulation experiment of the theoretical behavior model, and a control unit for controlling the measurement unit In the system, the theoretical operation model represents a physicochemical phenomenon that occurs in the controlled object by a mathematical formula, and is obtained by replacing individual arithmetic processing included in the mathematical formula with individual model components, The control behavior model is created so as to have a predetermined relationship such as an equivalent relationship with the theoretical behavior model based on a simulation result of the theoretical behavior model. Of the theoretical behavior model, and the functions of the measuring unit as those obtained by substituting the control operation of the control unit.

  Further, the measurement control system is based on a simulation code generator for generating a simulation code for the simulation unit to perform a simulation experiment based on the created theoretical behavior model, and on the created control behavior model. The control unit may include a control code generator that generates a control code for controlling the measurement unit.

  In the measurement control system configured as described above, since the measurement device, the simulation device, and the control device, which have been configured separately and independently, are integrated, the actual operation of the controlled object starts from the experiment stage by the simulation device. The transition work to the control device incorporation stage is facilitated, and the series of work from grasping the operation of the control object to the actual operation of the control object can be shortened. Also, not only theoretical experiments, but also experiments close to actual operation using actual measurement signals can be performed via the control unit, so there is no need to repeat experiments over time as in the past, The validity of the motion model can be easily improved sequentially.

  In addition, the measurement control system includes an analysis unit that selects any two signals from a plurality of signals input to the measurement unit and analyzes presence / absence or degree of a predetermined relationship such as a correlation between the two signals. The model creation unit can also reflect the analysis result of the analysis unit in the creation of the motion model.

  The model creation unit can reflect the analysis result of the analysis unit in the determination of the input / output signal or the determination of the parameter of the model component.

  The measurement control system configured as described above also has an analysis function such as obtaining a correlation between signals, so that an operation model of a control target having a complicated phenomenon can be easily created. It is possible to solve the problem by measuring another signal in the measurement unit while executing the signal.

  In addition, the measurement control system includes a display that displays any one of an operation model created by the model creation unit, a simulation experiment result of the simulation unit, a control result of the control unit, and an analysis result of the analysis unit. I can do it.

Since the measurement control system configured as described above has a display device, it is possible to create a visual motion model, and it is possible to clearly grasp the experimental result and the analysis result. In addition, since the display is integrated with the measurement control system, the experimental results and analysis results can be immediately reflected in the creation and correction of the motion model.

  According to the measurement control system according to the present invention, since the measurement device, the simulation device, and the control device that have been separately configured independently are integrated, the actual operation of the controlled object is started from the simulation stage by the simulation device. The transition work to the control device incorporation stage is facilitated, and a series of work from grasping the operation of the control object to the actual operation of the control object can be shortened, and development and manufacturing costs can be reduced.

  Since the measurement control system has an analysis function such as obtaining the correlation of signals, it is possible to create an operation model for a controlled object with a complicated phenomenon, or to perform another simulation at the measurement unit while executing a simulation via the control unit. It is effective in solving problems by measuring and analyzing signals.

  For example, at the beginning of the development of the system to be controlled, a simulation is performed using a theoretical behavior model, and then the simulation is performed in a state close to the actual operation using the data of the actual measurement signal, and the operation model is finely adjusted. Finally, a new method for developing an automatic control system is provided in which the accuracy of the operation model can be improved sequentially and easily by performing the operation check by actually operating the control target system.

  In addition, the measurement control system is an experimental device that has both a simulation function and an actual operation confirmation function not only in the technical field of automatic control but also in the development process of products (not required to be a control device) and in school education. Is available.

Furthermore, the measurement control system can be easily connected to the control target system at the site, and the results of measurement, operation model creation, analysis, and simulation can be easily displayed on the display unit. It can also be used for early troubleshooting and operation monitoring.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings. FIG. 1 shows an embodiment of a measurement control system 1 according to the present invention.

  1 includes a measurement unit 11, a memory 15, a simulation unit 25, a control unit 16, an analysis unit 17, an arithmetic processing unit 18, a display 19, a model creation unit 20, a model component storage unit 21, and a simulation. A code generator 22, a control code generator 23, and an operation input unit 24.

  The measurement unit 11 is a means for inputting and outputting signals related to the measurement control system 1. Specifically, the measurement control system 1 has a function of acquiring an effective factor as an input signal, and a function of outputting a control signal corresponding to the acquired input signal to the measurement control system 1, and is connected to the measurement control system 1. An arbitrary number of AD converters 12, DA converters 13, and I / O circuits 14 are arbitrarily combined in accordance with the controlled system 3 to be controlled.

  Here, the control target system 3 (control target) refers to a target controlled by the measurement control system 1 so as to satisfy a predetermined required performance. For example, an oil tank intended to maintain a constant temperature, This corresponds to the control target system 3.

  The AD converter 12 (input unit) is means for AD-converting an input signal related to any physical chemical phenomenon necessary for grasping, analyzing, and controlling the phenomenon of the controlled system 3. The signal AD-converted by the AD converter 12 is temporarily stored in the memory 15 for later control by the control unit 16 and analysis by the analysis unit 17.

  There are various types of input signals input to the AD converter 12 depending on the control target system 3. For example, there are time series signals such as temperature, water amount, torque amount, and weight detected by a sensor. As the sensor, a temperature sensor, a pressure sensor, or the like is selected according to the type of the input signal, and is installed in the control target system 3.

  The DA converter 13 (output unit) is mainly means for outputting a control signal supplied to the controlled system 3 from the control unit 16 and performing DA conversion. When the control signal is a repetitive rectangular wave, sine wave, or the like, it may be output directly from the signal generator, modulator, or the like without going through the DA converter 13.

  The I / O circuit 14 is an interface circuit used when the measurement control system 1 and the control target system 3 can exchange input / output directly with digital signals without going through the AD converter 12 or the DA converter 13. is there.

  For example, when the control target system 3 has a digital input unit, a digital signal output from the control unit 16 can be supplied to the control target system 3 via the I / O circuit 14, When the sensor installed in the control target system 3 has a digital output function, the output of the sensor can be input to the measurement control system 1 via the I / O circuit 14.

  The I / O circuit 14 may have a function of modulating and outputting an arbitrary input signal, or a function of changing the input / output direction of a signal in accordance with a command from the control unit 16. Also good.

  The simulation unit 25 is means for executing a simulation (simulation experiment) of a theoretical behavior model created by the model creation unit 20 based on a simulation code generated by a simulation code generator 22 described later.

  The control unit 16 controls the measurement unit 11 and the arithmetic processing unit 18 based on the control code generated by the control code generator 23 described later, and the actual operation of the control target system 3 and the model creation unit 20 It is means for executing a simulation based on an actual measurement signal for the created control action model.

  Specifically, the control unit 16 instructs the measurement unit 11 to input an arbitrary signal obtained from the control target system 3 at an arbitrary timing, period, resolution, sampling interval, or the like, or an AD converter 12, the DA converter 13, the I / O circuit 14, which channel of which means is selected, and how to set parameters such as input sensitivity and amplification factor.

  Further, the control unit 16 includes a control circuit (for example, a temperature PID control circuit) for outputting a control signal to the controlled system 3, and instructs the measurement unit 11 to output the control signal.

  In addition, the control unit 16 instructs the arithmetic processing unit 18 to select arbitrary data stored in the memory 15 and perform arithmetic processing necessary for the operation of the control circuit.

  The PID control is a proportional operation (P) that increases or decreases an operation amount in proportion to a deviation between a set value and a control amount, an integration operation (I) that increases or decreases an operation amount in accordance with the duration of the deviation, This control is a combination of three operations, ie, a differential operation (D) that increases or decreases an operation amount in accordance with a change in deviation, and is the most frequently used control method in the field of automatic control such as temperature control.

  The analysis unit 17 is a means for analyzing the presence or degree of a predetermined relationship such as a correlation for any two signals temporarily stored in the memory 15 or any two signals input to the measurement unit 11 in real time.

  The analysis result in the analysis unit 17 is executed before the operation model creation in the model creation unit 20 to be described later, and becomes a parameter determining factor in the operation model where the phenomenon is particularly complicated, or in the simulation unit 25 This is used for solving problems during simulation execution or during control execution of the control unit 16. The analysis result in the analysis unit 17 is stored in the memory 15.

  The arithmetic processing unit 18 is means for performing arithmetic processing based on a simulation code generated by a simulation code generator 22 described later and a control code generated by a control code generator 23. The arithmetic processing unit 18 also performs arithmetic processing necessary for analysis by the analysis unit 17.

  The arithmetic processing includes, for example, four arithmetic operations (addition / subtraction / division), amplification operation (fixed multiplication), logical operation (AND, OR, NOT, flip-flop, counter, etc.), function operation (average value operation, calculus operation, correlation function operation) Etc.), search for maximum / minimum peak values, etc., combined with these basic operations, filtering processing, delay time calculation, normalize (standardize the time axis and amplitude mutually) Calculation, weighting coefficient calculation, period calculation, FFT (Fast Fourier Transform) calculation and the like are included.

  These calculation processes are performed on one individual signal (calculus calculation, etc.) and between two or more signals or between a plurality of elements in one signal (for example, a time series signal) ( Correlation function calculation, normalization calculation, etc.).

  Further, these arithmetic processes become model components described later as individual functions.

  The display 19 is a means for displaying the calculation processing result in the calculation processing unit 18 as a numerical value or a graph. The calculation processing result here includes a simulation execution result in the simulation unit 25, a control execution result in the control unit 16, and an analysis execution result in the analysis unit 17.

  Further, the display 19 is controlled by the control unit 16 (for example, which AD converter 12 is currently selected and what signal is input, what the parameters are, and what control signal is output). It is also possible to display a GUI necessary for creating an action model in the model creation unit 20 described later and the created action model.

  The model creation unit 20 is a means for creating an operation model of the control target system 3. Here, the created behavior model includes a theoretical behavior model executed by the simulation unit 25 and a control behavior model executed by the control unit 16 based on an actual measurement signal.

  The general procedure for creating a theoretical behavior model is as follows: (1) grasping the physicochemical phenomenon occurring in the controlled system 3 → (2) formulating the physicochemical phenomenon → (3) replacing the formula with a model component.

  On the other hand, the control behavior model is created so as to have a predetermined relationship such as an equivalent relationship with the theoretical behavior model based on the simulation result of the theoretical behavior model, and among the theoretical behavior models executed by the simulation unit 25, the controlled system 3 itself. The part representing the operation (physicochemical phenomenon) is replaced with the control target system 3 itself, and the signal input / output function of the measuring unit 11 is further replaced with the control circuit of the control unit 16.

  Therefore, in order to create a control operation model, after creating a theoretical operation model, (4) a procedure for replacing the signal input / output function of the measurement unit 11 with the control circuit of the control unit 16 is required.

  In the process of grasping the physicochemical phenomenon in (1), it is necessary to determine an input / output signal for connecting the measurement control system 1 and the control target system 3, but the phenomenon of the control target system 3 is particularly complicated and the input When there are a large number of signal candidates, the signal input via the measurement unit 11 is analyzed by the analysis unit 17 before the operation model is created, and a large number of input signals are determined based on the degree of correlation between the input signals. The input signal necessary for the operation of the motion model can be determined from among the above, and the specific numerical values of the necessary parameters can be determined based on the analysis results.

  Note that the model creation unit 20 may create an operation model for determining input / output signals and parameters before creating an operation model of the control target system 3 itself. Further, the operation model for determining the input / output signals and parameters created here may be executable independently, or is a subroutine model (sub model) of the operation model of the controlled system 3. Also good. In this case, the operation model of the control target system 3 has a hierarchical structure.

  In the process of replacing the mathematical expression with the model component in (3), an arbitrary model component is selected from the model components stored in the model component storage unit 21 by operating the operation input unit 24 on the display 19. Select and determine the connections between model components, input / output signal specifications and various parameters.

  A model component is a block representing individual arithmetic processing (for example, differentiation, integration, addition, etc.) performed by the arithmetic processing unit 18 and individual functions (for example, switches, display, etc.) necessary for simulation and control. Yes, it can be decomposed into model components based on the formula created in (2).

  In the process of replacing the signal input / output function of the measurement unit 11 with the control circuit of the control unit 16 in (4), any model component from the model components stored in the model component storage unit 21 is the same as (3). However, the model components constituting the control operation model are basically connected to the controlled system 3 itself.

  The model constituent elements constituting the control operation model include, for example, an ON / OFF control circuit and a PID control circuit necessary for outputting a control signal from the measurement unit 11, and the AD converter 12 and the DA converter of the measurement unit 11. There are 13 control circuits.

  In order to determine parameters used by these control circuits, a model component that receives a signal from the measurement unit 11 and performs arithmetic processing in the arithmetic processing unit 18 may be connected to the control circuit.

  Since the model component is visualized so that its function can be understood (for example, a model component having an addition function is represented by “+”), the model is easily created on the display 19. I can do it.

  The simulation code generator 22 generates a simulation code for executing the individual functions of the model components by the simulation unit 25 and the arithmetic processing unit 18 based on the theoretical behavior model created by the model creation unit 20. It is means to do.

  The simulation code may be any code that can be input to the simulation unit 25 and operable by the simulation unit 25. However, if the simulation code is configured by a binary code, the simulation code can also be operated on a general personal computer. The simulation code is used for a simulation operation in the simulation unit 25 without going through the measurement unit 11 or the control unit 16.

  On the other hand, the control code generator 23 generates control codes for the control unit 16 to execute the individual functions of the model components based on the control operation model created by the model creation unit 20. Means. The control code is input to the control unit 16.

  The control code may be any code that can be input to the control unit 16 and can be operated by the control unit 16. However, if the control code is configured by a general-purpose programming code (for example, C ++), the control code is generally used or conventionally used. It can also operate on the control device.

  The control unit 16 controls the measurement unit 11 (settings related to input / output, output of control signals, etc.) and the arithmetic processing unit 18 based on the control code. As a result, not only the actual operation of the controlled system 3 but also the simulation for checking the control operation of the control unit 16 and the simulation close to the actual operation based on the actual measurement signal are executed.

  If the control unit 16 requires arithmetic processing in the arithmetic processing unit 18, the control unit 16 may instruct the analysis unit 17 to receive the arithmetic processing result of the arithmetic processing unit 18 from the analysis unit 17. The calculation processing result based on the simulation code may be reflected in the control code, or the control code may be directly input to the calculation processing unit 18. When the control code is input to the arithmetic processing unit 18, the arithmetic processing unit 18 needs to be able to decode the control code.

  Further, when an operation model for determining input signals and parameters is operated, the result of the arithmetic processing performed by the arithmetic processing unit 18 may be reflected in the control code generator 23 to be a control code.

  Conventionally, when executing simulation and control, it has been necessary to create a simulation code and a control code from scratch by programming.

  However, in the present invention, if the model creation unit 20 selects a model component using the GUI on the display 20 and connects the model components, the simulation code and control code corresponding to each function of the model component are provided. Since code is generated, there is no need for programming and the time required for model creation can be greatly reduced.

  In the past, when creating a theoretical behavior model, it was necessary to formulate the physicochemical phenomenon of the controlled system 3, but if the formula is a complex formula such as a differential equation, In order to obtain the solution, it is necessary to perform arithmetic processing such as Laplace transform, and it is necessary to perform programming separately for the arithmetic processing, and it takes time to obtain the solution of the mathematical expression.

  However, in the present invention, calculation processing functions such as differentiation and integration are already prepared as model components, and the model creation unit 20 connects the model components to each other to establish a mathematical expression on the display 19. Since a programming code (simulation code or control code) for obtaining a mathematical expression solution is generated, no prior programming is required.

  Here, an example from the behavior model created by the model creation unit 20 to the generation of the simulation code and the control code will be described based on a simple behavior model.

  FIG. 2 is an example of an operation model of the control target system 3 a created by the model creation unit 20. The control target system 3a in FIG. 2 is a system that keeps the water temperature in the water tank 45 constant according to the heating by the heater 43, and it is assumed that the required performance of the control target system 3a is to keep the water temperature constant.

  The system 3a to be controlled operates in accordance with a proportional relationship of y = Ax (A: constant), with the output signal y (for example, the temperature in the aquarium) changing according to the input signal x (for example, heater capacity). And

  In this case, the theoretical operation model C created by the model creation unit 20 includes a multiplication block that performs multiplication (or constant multiplication) of the input signal x and the constant A and outputs the output signal y as a model component. This model component is selected from the model component storage unit 21.

  The simulation code generator 22 generates a simulation code for the theoretical behavior model C created here. In this case, a program code is generated that allows the arithmetic processing unit 18 to execute arithmetic processing that multiplies the constant A and the variable x and outputs y.

  Based on the simulation code, the simulation unit 25 causes the arithmetic processing unit 18 to perform arithmetic processing, and outputs a multiplication result of a predetermined input x and a constant A to the display 19. Here, how to change the input x can be freely determined, and the input method of x here is reflected in the creation of the control operation model.

  The display 19 displays y as a multiplication result. Here, if y satisfies the required performance (having a constant value), it can be seen that the theoretical behavior model C created by the model creation unit 20 is valid.

  Next, the model creation unit 20 creates a control operation model. The control operation model is created so as to finally match the operation of the theoretical operation model C (y (water temperature) becomes constant) by the control unit 16 controlling x (heater capacity).

  Here, the control method of x is clarified by the simulation result in the simulation unit 25. For example, if the heater 43 is controlled so that the rated output of the heater 43 is maintained at 80%, y is constant. Suppose that a simulation result is obtained.

  In this case, the control operation model is obtained by replacing the signal input / output function of the measurement unit 11 with the control circuit of the control unit 16 in the created theoretical operation model C. For example, as shown in FIG. 2, a control circuit that outputs a control signal such that the rated output is maintained at 80% and inputs the control signal to the heater 43 via the DA converter 13 constitutes a control operation model.

  Further, in the control operation model of FIG. 2, a switch 26 for inputting a signal detected from the temperature sensor 41 to the AD converter 12 and displaying it on the display 19 is also a control operation model. include.

  The control circuit includes not only a function of outputting a control signal but also a function of controlling the AD converter 12 and the DA converter 13. Further, a control circuit that adjusts and outputs a control signal to the heater 43 based on the value of the output signal y input from the AD converter 12 may be included.

  The control code generator 23 generates a control code for the control unit 16 to execute the control operation model created by the model creation unit 20.

  Thus, the control code is generated as a program code for outputting a control signal from the control unit 16 through the DA converter 13 of the measurement unit 11 so that the heater 43 becomes 80% of the rated output, and further the temperature sensor. Y (water temperature) detected from 41 is input via the AD converter 12 of the measuring unit 11 and displayed on the display 19 via the switch 26, and the operation of the control operation model and the theoretical operation model match. The program code is such that the control unit 16 confirms the above. That is, the control operation model has a predetermined relationship such as an equivalent relationship with the theoretical operation model.

  Further, the control unit code includes a parameter as shown in the parameter setting screen D of FIG. 3 in order to control the AD converter 12 of the measuring unit 11, and the AD converter 12 is based on this parameter. Be controlled.

  Note that the parameter setting screen D as shown in FIG. 3 is displayed on the display 19 and is set from the operation input unit 24 when the model creation unit 20 creates the control action model. Here, as the parameters of the AD converter 12, for example, the system configuration (part number of the AD converter 12 to be used (AD7102)), the slot position where the AD converter 12 is inserted (slot No ([1])), sampling It can be seen that the type (sampling application (sound, vibration analysis)), sampling interval (reciprocal of sampling frequency (1/10000 seconds)), etc. are set.

  The theoretical operation model and the control operation model can coexist as shown in FIG. 2, and the generation of the simulation code and the control code is switched by switching the switch 26. Moreover, the simulation operation in the simulation unit 25 and the control operation based on the actual measurement signal via the control unit 16 may be performed simultaneously.

  Finally, after it is confirmed that the execution results of the theoretical operation model and the control operation model match, the control code of the control operation model is used for the actual operation of the controlled system 3.

  Here, when the behaviors of both models do not match, the creation of the behavior model is not correct. However, adjustment of the behavior model is easily performed by reselecting model components and re-inputting parameters.

  In addition, once the measurement unit 11 measures a signal necessary for control, the simulation can be performed in a short time using the signal, so that the validity of the operation model can be improved in a short time.

  Conventionally, the measurement device, analysis device, simulation device, and control device required to construct an automatic control system are configured separately and the operation model created on the simulation device can only be used for simulation purposes. In order to incorporate the operation model into the control device, it is necessary to separately program the operation model and to perform programming necessary for controlling the measurement device (corresponding to the measurement unit 11 in the present invention). did not become.

  Furthermore, when the operation of the control target system 3 is complicated, in order to create an operation model, it is necessary to reflect the analysis result of an analysis device that is completely incompatible with the simulation device, and the procedure is complicated. .

  However, in the measurement control system 1 of the present invention configured as described above, the measurement unit 11 corresponding to the measurement device, the control unit 16 corresponding to the control device, the analysis unit 17 corresponding to the analysis device, and the simulation device are equivalent. A simulation unit 25 is integrated.

  Furthermore, the behavior model created by the model creation unit 20 is not only a mere theoretical simulation in the simulation unit 25 but also a simulation including a control operation confirmation of the control unit 16 or a simulation based on an actual measurement signal. It does not take the time and effort required for the transition from simulation to actual system operation (system construction such as sensor placement, incorporation of the control device into the control target system 3, programming work for the control device, confirmation of actual operation, etc.) .

  Therefore, in the measurement control system 1 of the present invention, the conventional problems as described above do not occur, and a series of processes from grasping the operation of the control target system 3, creating an operation model, simulating the operation model, and actual operation of the control target system 3 are performed. The flow can be completed in the same place in a short period of time, contributing to a reduction in development cost at the development site and a reduction in production cost at the production site.

  The control code can also be input to the control unit 16 in another measurement control system 1 to control the control target system 3. In order for the control code generated by the control code generator 23 to be operated by the control unit 16 of another measurement control system 1, an interface with the control target system 3 (for example, two AD converters and one DA conversion). All you need to know is that you need them.

Thereby, it is not always necessary for the control target system 3 and the measurement control system 1 to correspond to each other. If the operation model created by the model creation unit 20 is stored in the memory 15, the control code generator 23 generates the control code, so that it is necessary to incorporate a measuring device and a control device for each controlled system 3. Absent. In addition, since a plurality of control target systems 3 can share one measurement control system, resource saving and space saving can be achieved.

  Hereinafter, detailed examples of the present invention will be described. FIG. 6 shows a configuration diagram of the metal object 3b that is the control target system 3 controlled by the measurement control system 1b and an outline of the connection between the measurement control system 1b and the metal object 3b. Note that the measurement control system 1b in FIG. 6 is configured by extracting only main components necessary for the description of the embodiment from the measurement control system 1 in FIG.

  The center of the cylindrical metal object 3b is hollow, and a heater 47 is embedded in this hollow portion. The required performance of the metal object 3 b is to keep the temperature of the entire metal object 3 b constant by heating the heater 47.

  Hereinafter, the process until the measurement control system 1b actually controls the temperature of the metal object 3b will be described based on the flowchart of FIG.

  The model creation unit 20 creates two types of behavior models (theoretical behavior model and control behavior model) (S410).

  In order to create the motion model, it is necessary to grasp the motion of the metal object 3b, the signal that is the motion factor, and determine the control signal. In this embodiment, the outline of the operation of the metal object 3b is as described above, and the required performance of the metal object 3b (maintaining the temperature of the metal object 3b constant) is satisfied by controlling the heater 47. However, at present, the heat dissipation characteristic (heat transfer characteristic) from the metal object 3b to the atmosphere is unknown.

  First, regarding the creation of the theoretical behavior model, it is necessary to formulate the physicochemical phenomenon occurring in the metal object 3b, and the formula is performed as follows.

(1) The amount of heat Q _S = 0.45 [kW, kJ / sec] generated from the 100V, 450W heater 47 is a heat source for increasing the temperature. Here, the heat quantity Q _S in the minute time Δt [sec] is Q _S = Ri ² Δt [kJ] (Equation 1).

(2) Assuming that the temperature of the metal object 3b that increases in a minute time Δt [sec] as the temperature of the heater 47 increases is ΔT (t) [K], the temperature rise heat quantity Q _A of the metal object 3b is Q _A = mcΔT (t) = ρ ₀ VcΔT (t) [kJ] (m: heater weight [kg], c: specific heat [kJ / (kg * ° C.)], ρ ₀ : heater density, V: heater volume [m ³ ]) (Expression 2).

(3) heater dissipating heat _{Q O} to dissipate the difference between the temperature and the atmospheric temperature of the metal object. _{3b, Q O = hS △ T (} t) = hS (T (t) -T R) (h: a metal Heat transfer coefficient to the atmosphere [kW / m ² * K], S: heater surface area [m ² ], T _R : air temperature [K]) (Equation 3).

Each equation of (1) to (3) is expressed as a thermal equilibrium formula: heat generated by the heater 47 (Q _S ) = temperature rising heat of the metal object 3b (Q _A ) + heat radiation heat from the metal object 3b to the atmosphere (Q _{O 2} ), Ri ² Δt = ρ ₀ VcΔT (t) + hS (T (t) −T _R ) Δt (Equation 4).

When the above equation is shifted and both sides are divided by Δt to form a differential equation of T (t), ρ ₀ VcΔT (t) / dt + hST (t) = Ri ² + hST _R (Equation 5) )

Furthermore, when the above equation is transformed into a Laplace function, ΔT (t) / dt = s and T (t) = {Ri ² −hS ((T (t) −T _R )) / ( ρ ₀ Vcs) (Expression 6)

Conventionally, it is necessary to obtain a solution of the first-order differential equation of the above equation instead of correcting it to the Laplace function, and it is necessary to perform a Laplace transform or the like (the solution is T (t) = {Ri ² −hST _R } / (hS) * [1-e (− (hS)) t / (ρ ₀ Vc)]), but in this embodiment, it is not necessary to obtain the solution of the differential equation.

  The above formula (formula 6) corrected to the Laplace function is divided into each model component of the arithmetic processing and simulation function, the divided model component is extracted from the model component storage unit 21, and the operation input unit 24. An example of the theoretical operation model E selected by the operation input unit 24 and connected to each other by the operation input unit 24 and created by the model creation unit 20 on the display 19 is shown in the upper part of FIG.

  The lower part of FIG. 7 is obtained based on the known constants (surface area, volume, density, specific heat, atmospheric temperature, etc.) in the theoretical operation model E of the upper part of FIG. A state where a specific numerical value such as a parameter is input and a display function (“Display” in the figure) for displaying the numerical value of T (t) as a simulation result on the display 19 is selected as a model component This is the theoretical operation model F.

  In FIG. 7, the heater corresponds to Heater, the atmospheric temperature corresponds to Room Temp, the surface area corresponds to Heter Area, the heat transfer coefficient corresponds to Cond Coeff, the volume corresponds to Heater Volume, the density corresponds to Mituto, and the specific heat corresponds to Hinetu. doing.

  Further, when the parameter is not fixed, it may be changed by a manual operation in a simulation process described later. In the theoretical operation model F in the lower part of FIG. 7, since the heat transfer coefficient (Cond Coeff) is unknown, an appropriate numerical value (0.016) is input.

  Since the model components are visualized as shown in FIG. 7, the user can easily create a theoretical behavior model without the need for language programming.

  Further, the model creation unit 20 creates a control operation model (S410). The creation of the control behavior model does not have to be performed at the same time as the creation of the theoretical behavior model, and the control behavior model may be created after executing the simulation of the theoretical behavior model.

  The control operation model is a model that has a predetermined relationship such as an equivalent relationship with the theoretical operation model, and in the theoretical operation model, the signal input / output function of the measurement unit 11 is replaced with a control operation performed by the control unit 16. FIG. 8 is a connection conceptual diagram of the metal object 3b and the operation model, and is an example in which the theoretical operation model E and the control operation model G created earlier are displayed together.

  In FIG. 8, portions corresponding to model components of the control operation model G are a heater control circuit 27, an AD converter control circuit 28, and a comparator 29.

  The heater control circuit 27 outputs a control signal, and the control signal is input to the heater drive circuit 49 to operate the heater 47.

  The AD converter control circuit 28 controls the AD converter 12 to store the temperature of the metal object 3 b detected from the temperature sensor 41 in the memory 15.

  The comparator 29 compares the signal input via the AD converter 12 with the signal obtained as a result of the simulation of the theoretical operation model E, and displays the comparison result on the display 19.

  The theoretical motion model E is obtained by replacing the operation of the metal object 3b which is the control target system 3, and the operation of the metal object 3b and the operation of the theoretical operation model E are essentially the same. Therefore, the model creator determines the theoretical motion model E in the following procedure, and then makes the motion of the metal object 3b coincide with the theoretical motion model E, that is, equivalent to the theoretical motion model E. The control operation model G is determined so that a predetermined relationship such as a relationship is obtained, and each model is adjusted so that the operations of both models finally match.

  Based on the generated theoretical behavior model E, the simulation code generator 22 generates a simulation code for executing the individual functions of the model components in the simulation unit 25 (S420).

  The simulation code is prepared for each model component, and as long as the model is created, there is a simulation code that realizes arithmetic processing functions such as differentiation and integration. It is not necessary to perform Laplace transform for solving, and the differential equation can be solved.

  Based on the simulation code, the simulation unit 25 executes an operation simulation of the metal object 3b without using the measurement unit 11 or the control unit 16 (S430). That is, the simulation code does not have a code for interface with the measurement unit 11 and the control unit 16, and the control unit 16 and the measurement unit 11 do not operate at this simulation stage.

  The simulation result is displayed on the display 19. Thereby, it is determined whether or not the required performance of the metal object 3b (control target system) is satisfied (S440).

  An example of the simulation result is shown in FIG. FIG. 9 shows the display 19 of the elapsed time (horizontal axis) and the temperature (vertical axis) of the metal object 3b based on the waveform display (Scope) function, which is a model component included in the theoretical behavior model F of FIG. Is the result displayed in

  The required performance in the present embodiment is that the temperature of the metal object 3b is controlled to be constant. From FIG. 9, it is understood that the temperature is maintained constant at about 420 ° C. after about 4000 seconds. I understand.

  If the required performance of the system is satisfied, it can be seen that the theoretical operation model E created by the model creation unit 20 is appropriate. If the required performance is not satisfied, review the input / output signals of the created behavior model and fine-tune model components and parameters, and follow the procedure from S410 to S430 (operation model until the required performance is satisfied. Repeat from creation to simulation.

  When the validity of the theoretical operation model E is confirmed by the previous simulation, the control code generator 23 generates a control code for the control operation model G (S450).

  The control code is a code for the control unit 16 to execute the control operation model G, and is obtained based on the simulation result of the previous theoretical operation model E. For example, if the heater 47 is turned on / off at intervals of 5 seconds in the simulation performed by the simulation unit 25, a programming code for outputting a control signal to the heater 47 at intervals of 5 seconds is generated. To do.

  The control code may include a program for analyzing an arbitrary signal input to the measurement unit 11 by the analysis unit 17 and inputting a result calculated by the calculation processing unit 18 to the control unit 16. Good. Thereby, the control unit 16 can also perform feedback control such that the control signal is output based on the output signal obtained from the temperature sensor 41 (for example, the temperature T (t) of the metal object 3b).

  The control code generator 23 generates a control code for executing this control operation (control signal output, input signal acquisition via the AD converter 12, etc.) and inputs it to the controller 16.

  Based on the control code, the control unit 16 controls the measurement unit 11 to execute an operation simulation of the metal object 3b (S460).

  In the simulation of S460, a control signal output from the DA converter 13 (not shown) of the measurement unit 11 via the control unit 16 is input to the heater drive circuit 49, the heater 47 is operated, and the metal object 3b is moved. A signal from the temperature sensor 41 that is heated and installed on the metal object 3 b is input to the AD converter 12 of the measuring unit 11.

  A simulation result based on the actual measurement signal is displayed on the display 19. Thereby, it is determined whether or not the required performance of the metal object 3b is satisfied (S470). Here, if the required performance of the metal object 3b is satisfied, it can be seen that both the theoretical motion model E and the control motion model G created by the model creation unit 20 are valid. When the required performance of the metal object 3b is not satisfied, the process returns to the creation of the operation model in S410, and the theoretical operation model E or the control operation model G is readjusted.

  An example in which the simulation result A of the control behavior model G via the control unit 16 and the simulation result B of the previous simulation unit 25 are displayed together is shown in FIG. Both simulation results A and B in FIG. 10A do not match, indicating that either the theoretical behavior model E or the control behavior model G is incorrect.

  In pursuit of the reason why the simulation results of both models do not match, the heat transfer coefficient h is unknown in the first place, and the value (0.016) of the input heat transfer coefficient (Cond Coeff) h is appropriate at the beginning of the theoretical operation model creation. The hypothesis that there is no is born.

  Therefore, the model creation unit 20 changes the input value of the heat transfer coefficient h of the theoretical operation model F created as shown in the lower part of FIG. 7 from the initial value of 0.016 to 0.018, and then performs simulation again. The unit 25 is caused to execute a simulation.

  The result is shown in FIG. The simulation result B of the theoretical behavior model E in FIG. 10A is modified as compared with FIG. 9 by changing the value of the heat transfer coefficient h of the theoretical behavior model E, and becomes the simulation result B ′. The result was close to the simulation result A of the control operation model G performed. Thereby, it can be seen that the true heat transfer coefficient h is 0.018.

  In this way, by creating a theoretical behavior model and a control behavior model, simulating both models, and comparing whether they match, the value of an unknown parameter that cannot be actually measured by a sensor etc. Can also be estimated.

Finally, when the control operation model G to be used for the actual operation of the metal object 3b is determined, a control code based on the control operation model G is input to the control unit 16, and the actual control target system is executed. The operation is started (S480).

  Next, another embodiment of the present invention will be described. The control target system 3 in the present embodiment is a two-tank oil circulation thermostat 3c.

  The 2-tank oil circulation thermostatic chamber 3c is mainly used to reduce the coefficient of friction generated between automobile parts (pumps, compressors, bearings, brakes, pistons, etc.) and lubricating oil. It is used when making a design (selecting material, surface processing method, coding material for parts, selecting oil and additives for lubricating oil).

  In such an optimized design, the test object (parts) is rotated or slid in the thermostatic chamber and the test is performed. Therefore, not only the test object but also the oil itself generates heat and becomes high temperature. The temperature in the tank is likely to change.

  However, a rapid and large change in the oil temperature affects the measurement of the frictional characteristics of the test object, and correct test results cannot be obtained. Therefore, it is required that the oil temperature in the thermostatic bath be maintained constant.

  Further, in this embodiment, since the oil itself is the DUT as well as the part, the capacity and material of the oil are specified in the test method, and it is not possible to change the specifications of the oil itself to keep the oil temperature constant. I can't.

  Therefore, normally, in such an optimization design, the internal oil tank in which the oil capacity and material are determined and the outer oil tank with a degree of design freedom are configured as two tanks, and the oil temperature of the inner oil tank is set to the outer oil tank. By controlling indirectly from the above, rapid temperature change including internal heat generation in the inner oil tank can be suppressed.

  As shown in FIGS. 11 and 12, the two-tank oil circulation and thermostat 3 c includes an inner oil tank 31, an outer oil tank 32, an inner oil tank oil source 33, an outer oil tank oil source 35, and heaters 34 and 36. , Pumps 37 and 38 and pipes 39 and 40.

  Hereinafter, an outline of the operation of the two-tank oil circulation thermostat 3c will be described. The oil in the inner oil tank 31 is obtained by heating the oil in the inner oil tank oil source 33 with the heater 34 and circulating it with the pump 37 through the pipe 39. Similarly, the oil in the outer oil tank 32 is also obtained by heating the oil in the outer oil tank oil source 35 with the heater 36 and circulating it with the pump 38 through the pipe 40.

  Thus, the two-tank oil circulation thermostat 3c has two oil circulation paths, and the oil temperature in the outer oil tank 32 is transferred to the inner oil tank 31 so that the oil temperature in the inner oil tank 31 is reduced. Maintained constant. Moreover, rapid temperature changes can be suppressed by circulating the oil in the oil tank without directly heating it. When the oil temperature is lowered, heating of the heaters 34 and 36 is stopped or the oil source is cooled with tap water.

  In this embodiment, the measurement control system 1c shown in FIGS. 11 and 12 uses the two-tank oil circulation thermostat 3c as the control target system 3, and sets the oil temperature of the internal oil tank 31 having a capacity of 50 liters to 40. Control can be made so that the temperature can be changed to a temperature set in the range of from 300 ° C. to 300 ° C., and within the range of ± 1 ° C. after setting.

  Hereinafter, the process until the measurement control system 1c actually controls the oil temperature of the inner oil tank 31 of the two-tank oil circulation thermostat 3c is shown in FIG. 11 and FIG. 12, and FIG. 4 and FIG. It demonstrates based on the flowchart of these. Note that the measurement control system 1c shown in FIGS. 11 and 12 is configured by extracting only main components necessary for the description of the embodiment from the measurement control system 1 shown in FIG.

  The model creation unit 20 creates an operation model of the two-tank oil circulation thermostat 3c (S410).

  In order to create an operation model, it is necessary to understand the operation of the two-tank oil circulation thermostatic chamber 3c, the signal that is the operation factor, and the determination of the control signal. In this embodiment, the outline of the operation of the two-tank oil circulation thermostat 3c is as described above, and the two-tank oil circulation thermostat 3c is controlled by controlling the current of the heaters 34, 36, the pressure of the pumps 37, 38, and the like. The required performance (maintaining the oil temperature of the inner oil tank 31 constant) is satisfied.

  As a matter of course, the signal that is an operating factor indicates a signal that can be an oil temperature determining factor of the inner oil tank 31, but the oil temperature of the two-tank oil circulation thermostat 3c as in this embodiment is determined. In addition to the oil source temperature in the inner oil tank, the outer oil tank temperature, the outer oil tank oil source temperature, the atmospheric temperature, the oil properties (quantity, specific heat, density, heat transfer rate, etc.), tap water properties, pump capacity, heater Many factors such as capacity and pipe capacity are involved.

  Therefore, it is difficult to specify the signal that is the operating factor simply by grasping the operation of the two-tank oil circulation thermostat 3c, and even if it is specified, it is composed of a large number of signals. In this case, since the creation and operation of an operation model becomes complicated, it is not suitable for the actual operation of the measurement control system 1c. In creating an operation model, it is necessary to determine parameters necessary for control.

  Therefore, the measurement control system 1c performs signal analysis according to the procedure of FIG. 5 before creating an operation model in the model creation unit 20 in S410, and identifies a signal that is an operation factor, And parameters are determined.

  First, the measurement part 11 measures the signal acquirable from the 2 tank type oil circulation thermostat 3c (S510). Here, the internal oil tank temperature, the internal oil tank oil source temperature, the external oil tank temperature, the external oil tank oil source temperature, and the atmospheric temperature are detected from the temperature sensor 41 installed in each part and input to the AD converter 12 of the measuring unit 11. . The cooling water amount is also input to the AD converter 12 of the measuring unit 11.

  The analysis unit 17 analyzes the signal measured by the measurement unit 11 (S520). In this embodiment, since temperatures from a large number of temperature sensors 41 are input, the correlation coefficient between the inner oil tank temperature and each of the other temperatures is obtained by the arithmetic processing unit 18 and is the most important factor for determining the oil temperature. Analyzes such as analysis of effective signal components that are highly relevant to the internal oil bath temperature. In accordance with the analysis result, the model creation unit 20 determines a control signal and parameters (S530).

  As a result of the correlation coefficient calculation in the analysis unit 17, for example, when it is found that the outer oil tank temperature has the highest relevance as the oil temperature determining element of the inner oil tank 31, the model creation unit 20 A weighting coefficient (one aspect of parameters) is given so that the numerical value of the oil tank temperature is used for oil temperature control with the highest priority.

  If the operation of the controlled system 3 is simple and it is easy to create an operation model, or if control signals and parameters can be easily determined, the procedure of FIG. 5 and the analysis by the analysis unit 17 are not necessary. is there.

  The model creation unit 20 creates the theoretical operation model of the two-tank oil circulation thermostat 3c after performing the analysis as described above as necessary. The theoretical operation model is composed of a plurality of submodels when the operation of the control target system 3 is complicated as in this embodiment, and the submodels are connected to each other, and the oil temperature of the inner oil tank 31 is finally output. Although calculated | required as a result, the case where the submodel which represents the oil circulation operation | movement of the inner oil tank 31 by a heat balance is produced is demonstrated here.

  When the heat balance calculation regarding the oil circulation of the inner oil tank 31 is performed, it is as follows.

(1) When an electric current is supplied to the heater 34 to heat the heater 34, a heat amount (heater heat amount) Φ _S2H for giving a heat amount to the oil is generated. Φ _S2H at this time is Φ _S2H = Ri ² Δt [kW or kJ / sec] (R: heater resistance [Ω], i: heater current [A]) (Expression 7).

(2) The oil temperature T of the inner oil tank oil source 33 rises. The amount of heat (oil source heat amount) Φ _S2 generated at this time is Φ _S2 = mc ₀ ΔT (t) = ρ ₀ Vc ₀ ΔT (t) [kJ], ΔT (t) = T−T _B (m : oil capacity [kg], _{c 0:} oil specific heat [kJ / (kg × ℃) ,], ρ 0: oil density ^{[kg / m 3], V} : the internal oil tank volume ^[m 3], _{T B:} inner oil vessel The return oil temperature [° C.] of the oil source 33) (Equation 8).

(3) the amount of heat (tap water cooling release heat) [Phi _S2W generated when the oil temperature of the oil bath fluid source 33 decreases with tap _{water, Φ S2W = S W v W} c W △ T = ρ W q W c W ΔT [kJ / sec], ΔT = T−T _W (S _W : sectional area of water [m ² ], v _W : tap water flow velocity [m / sec], c _W : specific heat of water [kJ / (kg × ° C)], ρ _W : water density [kg / m ³ ], q _W = tap water flow rate [m ³ / sec], T _W : tap water temperature [° C.]) (Equation 9).

(4) The amount of heat (oil source dissipated heat amount) Φ _S generated by heat dissipation from around the inner oil tank oil source 33 is Φ _S = hA _S2 ΔT, ΔT = T−T _R [kJ / sec] (h : Heat transfer coefficient [kW / (m ² × K × sec)], A _S2 : inner oil tank oil source surface area [m ² ], T _R : atmospheric temperature [° C.]) (Equation 10).

(5) The amount of heat (oil circulation discharge heat amount) Φ _SO generated when heated oil flows out from the inner oil tank oil source 33 through the pipe 39 is Φ _SO = A _p v ₀ c ₀ ΔtΔT, ΔT = T-T _B (A _p : pipe cross-sectional area [m ² ], v ₀ (or q ₀ ): hot oil flow velocity [m ³ / sec], c ₀ : hot oil specific heat [kJ / (kg × ° C.)] ) (Equation 11).

These heat balance equations (1) to (5) are _{expressed as follows} : Φ _S2H Δt = Φ _S2 + Φ _S2W Δt + Φ _S Δt + Φ _SO Δt [kJ] (equation 12) )

Equation 12 is transformed in the same manner as in the first embodiment, and ΔT (t) / dt = s, and an expression relating to T (t) is obtained, {ρ ₀ Vc ₀ s + (ρ _W q _W c _{W + ρ 0 q 0 c 0} + hA S2)} becomes ^{T (t) = Ri 2 +} ρ W q W c W T W + ρ 0 q 0 c 0 T B + hA S2 T R ··· ( number 13).

  FIG. 13 shows an example of the theoretical behavior model H that is obtained by dividing the above equation (Equation 13) into each model component and actually created by the model creation unit 20 on the display 19.

  The theoretical behavior model H in FIG. 13 is extracted from the model component storage unit 21 and selected by the operation input unit 24, and the model input components 24 are selected by the operation input unit 24, as in the first embodiment. It is created by connecting.

  Furthermore, a theoretical operation model in which parameters such as a known constant or a constant based on an analysis result are input to the theoretical operation model H of FIG. 13 can be created. When the parameters are not fixed, a theoretical operation model may be created so that the parameters can be changed by manual operation in the simulation process described later.

  Based on the created theoretical behavior model H, the simulation code generator 22 generates a simulation code for performing the individual arithmetic processing functions of the model components in the arithmetic processing unit 18 (S420).

  For example, the simulation code created from the theoretical behavior model H in FIG. 13 performs an output process (T which is the solution of Equation 13) by executing arithmetic processing of mathematical expressions (sets of individual model components) in the submodel. (T)) is output.

  Based on the simulation code, the simulation unit 25 executes an operation simulation of the two-tank oil circulation thermostat 3c without using the measurement unit 11 and the control unit 16 (S430). That is, the simulation code does not have a code for interface with the measurement unit 11 and the control unit 16, and the control unit 16 and the measurement unit 11 do not operate at this simulation stage.

  The simulation result is displayed on the display 19. Thus, it is determined whether or not the required performance of the two-tank oil circulation thermostat 3c (control target system) is satisfied (S440). The required performance in the present embodiment is that the oil temperature in the inner oil tank 31 is controlled to be constant.

  If the required performance of the system is satisfied, it can be seen that the theoretical operation model created by the model creation unit 20 is valid. If the required performance is not satisfied, review the input / output signals of the created behavior model and fine-tune model components and parameters, and follow the procedure from S410 to S430 (operation model until the required performance is satisfied. Repeat from creation to simulation.

  The required performance in the present embodiment is that the oil temperature of the inner oil tank 31 is controlled to be constant, but actually, in addition to this, the time required for the oil temperature to be constant (responsiveness) and the initial The transient state is also an item when examining the quality of the motion model.

  Here, in FIG. 14 to FIG. 16, simulation code is generated from the simulation code generator 22 based on the three patterns of theoretical operation models created for the two-tank oil circulation thermostat 3c, and the simulation is performed. The result is displayed on the display 19. The required performance here is that the oil temperature of the inner oil tank 31 is controlled to 200 ° C. ± 1 ° C.

  The theoretical operation model that is the basis of the simulation result of FIG. 14 is that PID control is performed so that the oil circulation route of the inner oil tank 31 and the oil circulation route of the outer oil tank 32 are independently 200 ° C. This is performed for the heater 34 of the inner oil tank oil source 33 and the heater 36 of the outer oil tank oil source 35.

  The theoretical operation model that is the basis of the simulation result of FIG. 15 does not circulate the oil in the inner oil tank 31, but only heats the heater 36 of the outer oil tank oil source 35 to circulate the oil. The PID control to be 200 ° C. is performed on the heater 36 of the outer oil tank oil source 35.

  The theoretical operation model that is the basis of the simulation result of FIG. 16 is that the heater 36 of the outer oil tank oil source 35 is heated to circulate the oil, and PID control is performed so that the oil temperature of the inner oil tank 31 becomes 200 ° C. This is performed for the heater 36 of the oil source 35.

  (A) of each figure from FIG. 14 to FIG. 16 represents the time series change of the oil temperature of the outer oil tank 32 and the outer oil tank oil source 35, and (b) shows the oil temperature of the inner oil tank 31 and the inner oil tank oil source 33. (C) is an enlarged view of part of the time-series change in the oil temperature of the inner oil tank 31 and the inner oil tank oil source 33 in (b), and (d) shows the change from the outer oil tank 32 to the inner oil tank. 31 represents a time-series change in the amount of heat transfer to 31. 14 and 16 (e) show the time series change of the PID control waveform performed on the outer oil tank oil source 35, and FIG. 14 (f) shows the PID performed on the inner oil tank oil source 33. It represents the time series change of the control waveform.

  The graph (d) is an estimated heat transfer amount calculated by the calculation processing unit 18 based on the graphs (a) and (b) and preset parameters, and is not an actual measurement value.

  As can be seen from the simulation results of FIG. 14, there is about 150 W of heat transfer from the outer oil tank 32 to the inner oil tank 31 in the transient state as shown in FIG. 14 (d), but there is almost no heat transfer in the steady state. Therefore, the control loops of the outer oil tank 32 and the inner oil tank 31 have little influence on each other, and the temperature control can be performed relatively easily by the operation model created in FIG.

  It can be seen from the simulation results in FIG. 15 that the oil temperature in the outer oil tank 32 is controlled to be 200 ° C., so that the oil temperature in the inner oil tank 31 is constant at about 188 ° C. as shown in FIG. Thus, the required performance cannot be satisfied only by controlling the oil temperature of the outer oil tank 32. In addition, from FIG.15 (d), it turns out that the heat transfer from the outer oil tank 32 to the inner oil tank 31 is about 40W.

  It can be understood from the simulation result of FIG. 16 that the oil temperature of the inner oil tank 31 is controlled to be 200 ° C., so that the oil temperature of the inner oil tank 31 is constant at 200 ° C., but can be understood from the enlarged view of FIG. As such, the oil temperature is unstable. However, although it is unstable, the deviation is ± 0.2 ° C., and the operation model created in FIG. 16 satisfies the required performance for the time being.

  Summing up all the above simulation results, it was confirmed that the theoretical operation model created in FIGS. 14 and 16 satisfies the required performance of the two-tank oil circulation thermostat 3b.

  Further, in order to satisfy the required performance with certainty and precision, actual measurement using a sensor or the like of heat transfer characteristics from the outer oil tank 32 to the inner oil tank 31, control of the flow rate of tap water for cooling water, Capacity optimization is required.

  If heat transfer characteristics cannot be measured as in this example, a theoretical operation model and a control operation model are created, and the model is adjusted so that the simulation results of both models match. As in Example 1, it is possible to estimate true heat transfer characteristics.

  The description of the flowchart after the validity of the theoretical operation model is confirmed by the simulation in the simulation unit 25 will be described with reference to the system configuration diagram of FIG. Here, it is assumed that the theoretical behavior model that is the basis of the simulation result shown in FIG. 14 is adopted.

  The control code generator 23 of the measurement control system 1c of FIG. 12 generates a control code for the operation model whose validity has been confirmed by the previous simulation (S450).

  The control code is a code for the control unit 16 to execute a control operation model obtained based on the simulation result of the previous theoretical operation model. The control operation model is a two-tank oil circulation circuit among the theoretical operation models. It is obtained by substituting the control circuit of the measuring unit 11 for the part that inputs and outputs signals with the thermostat 3c.

  In the present embodiment, a temperature control circuit (ON / OFF circuit for the heaters 34 and 36, a PID control circuit, a parameter calculation circuit, an alarm circuit, etc.) for outputting a control signal via the measurement unit 11, a measurement unit control circuit A control code composed of (a setting circuit for the input signal of the AD converter 12 and the output signal of the DA converter 13) is generated. The control operation model that is the basis of this control code is arranged along with the theoretical operation model so that the operations of the simulation unit 25 and the control unit 16 are switched by a switch.

  The control code may include a program for analyzing an arbitrary signal input to the measurement unit 11 by the analysis unit 17 and inputting a result calculated by the calculation processing unit 18 to the control unit 16. Good.

  The control code generator 23 generates a control code for executing this control operation and inputs it to the control unit 16.

  Based on the control code, the control unit 16 controls the measurement unit 11 to execute an operation simulation of the two-tank oil circulation thermostat 3c (S460).

  In the simulation of S460, a signal from the temperature sensor 41 installed in each part of the two-tank oil circulation thermostat 3c is input to the AD converter 12 of the measurement unit 11. Further, the result of arithmetic processing of these input signals by the arithmetic processing unit 18 via the control unit 16 is used as a control signal, from the DA converter 13 of the measuring unit 11 to the heater 34 of the inner oil tank oil source 33 and the outer oil tank oil. It is supplied to the heater 36 of the source 35.

  Therefore, the heaters 34 and 36 increase / decrease the heater current and turn on / off the heaters 34 and 36 based on the control signal input by the PID control, and finally control the oil temperature of the inner oil tank 31 to be constant. .

  In addition, the control part 16 preserve | saves the required signal from the AD converter 12 of the measurement part 11, and the analysis result of the signal before S460 as needed, and controls 2 tank type oil circulation thermostat 3c. You may use for.

  The simulation result is displayed on the display 19. Thereby, it is determined whether or not the required performance of the two-tank oil circulation thermostat 3c is satisfied (S470). Here, if the required performance of the two-tank oil circulation thermostat 3c is satisfied, it can be seen that the operation model created by the model creation unit 20 is finally valid. If the required performance of the two-tank oil circulation thermostat 3c is not satisfied, the operation model is readjusted and the operation model is readjusted.

  Note that the simulation in S460 is a simulation in which the control unit 16 controls the measurement unit 11 and actually inputs and outputs signals. Therefore, the simulation is limited to the actual operation rather than the simulation performed by the simulation unit 25 in S430. It is done in a close state.

  In addition, if the measurement unit 11 has measured a signal in advance for analysis or the like before the simulation, the simulation can be performed using the signal, which is shorter than the actual operation of the system. The simulation result is displayed on the display 19 with time.

  Conventionally, since the simulation apparatus and the control apparatus are separate, the simulation program for the simulation apparatus and the control program for the control apparatus must be created separately. Even if the operation is confirmed by simulation, when the control target system is operated by the control device, it is necessary to perform the experiment because the control program cannot be confirmed unless it is actually operated. .

  In particular, in the case of a constant temperature bath with a large amount of oil, it takes 1 hour or more for one temperature equilibrium measurement, and it requires a repeated experiment to confirm the control operation, and it takes one day. There was a problem.

  However, in this embodiment, since the operation of the control unit 16 that is also used for the actual operation of the controlled system can be confirmed by simulation, once the necessary signal data is fetched from the measurement unit 11, the data is used. In addition, since it is a simulation, the time axis can be advanced and the experiment does not take much time as in the past.

  Even if the simulation result shows that the created operation model is not valid, the operation model can be easily fine-tuned using the GUI on the display 19, and the simulation can be resumed immediately. I can do it.

  Further, when there is a problem with the created operation model, the control unit 16 performs a control operation with the operation model and simultaneously measures a signal that can be a factor in the measurement unit 11 and analyzes it in the analysis unit 17. It is possible to perform factor analysis without interrupting the control loop. Even if the simulation unit 25 is executing a simulation, a signal from the measurement unit 11 can be input.

Finally, when the operation model to be used for the actual operation of the two-tank oil circulation thermostat 3b is determined, a control code based on the operation model is input to the control unit 16 to execute the actual control target system. The operation is started (S480).

  As described above, even when the behavior model cannot be narrowed down to one at the beginning of development, if a plurality of assumed behavior models are created and simulation is performed for each by the simulation unit 25 or the control unit 16, the operation can be performed in a short time. Validity and comparison of models can be performed. In addition, once the necessary signal is captured from the measurement unit 11, the data of the signal can be used for checking the control operation of the control unit 16 in common with any operation model. There is no need to do it.

  In this way, using the measurement control system 1 of the present invention, at the beginning of development, simulation is performed using a theoretical operation model, and then actual operation via the measurement unit 11 is performed using data of actual measurement signals. The simulation of the control operation model is performed in a state close to, the operation model is finely adjusted, and finally the operation target system 3 is actually operated to check the operation, thereby improving the accuracy of the operation model sequentially and easily. A new method for developing an automatic control system is provided.

  Conventionally, since a simulation device and a control device have been prepared separately, there is no predetermined relationship such as an equivalence relationship between the created theoretical behavior model and the control behavior model, especially when trouble occurs. Somehow, there was a tendency to deal with the problem by simply changing the control operation model of the control device, and the root cause of the trouble was not pursued, such as checking the validity of the theoretical operation model.

  However, if a correct theoretical behavior model and a control behavior model having a predetermined relationship such as an equivalent relationship with this theoretical behavior model are determined by this development method, specification change or trouble occurred in the controlled system 3 later. Even at times, it becomes easier to pursue which part of the model has changed and which part is causing the trouble, leading to a fundamental solution.

Further, the model can be easily changed on the display 19 and the signal can be measured while performing the simulation, so that it is possible to quickly cope with the specification change and trouble.

  In addition to the embodiments described above, the measurement control system 1 according to the present invention is not limited to the technical field of automatic control, but also has a simulation function and a practical application not only for the development process of products (not necessarily control devices) but also for school education. It can be used as an experimental device with an operation confirmation function.

  For example, in the course of electrical / mechanical control subjects such as technical colleges, universities, graduate schools, etc., if there is one measurement control system 1 per person or group, theoretical learning about the control target system 3 (physical chemistry phenomena) Grasping, operation model creation, simulation) and control operation confirmation by operating the control unit 16 and actually performing signal measurement can be performed at a time.

  As a result, the lecture and the experiment are not performed separately as in the conventional case, and the lecture and the experiment can be performed in the same place in a short time. Students can experience the importance of linking lectures and experiments.

  Moreover, it is no longer necessary for students to code a simulation program and a control program for experiments separately, and students can bother language programming (two types of simulation and control languages if different) Students will be provided with a meaningful lecture and experimental field on control subjects.

Furthermore, the measurement control system 1 can be easily connected to a control target system in the field, and can easily display the results of measurement, operation model creation, analysis, and simulation on the display 19. It can also be used for early troubleshooting of target systems and operation monitoring.

It is a block diagram of the measurement control system concerning this invention. It is an example of an operation model. It is an example of an operation model parameter setting screen. It is a flowchart figure which shows the procedure from the operation | movement model creation by a measurement control system to the actual operation | movement of a control object system. FIG. 5 is a flowchart showing a procedure for determining a measurement target and parameters performed when creating an action model in the flowchart of FIG. 4. It is a connection outline figure of a measurement control system concerning the present invention, and a metal object. It is an example of the operation | movement model of metal objects. It is a conceptual diagram showing the relationship between a metal object and an action model. It is a graph which shows the simulation result of the motion model of metal objects. It is another graph which shows the simulation result of the motion model of metal objects. It is a block diagram of the measurement control system concerning this invention, and a 2 tank type oil circulation thermostat. It is another block diagram of the measurement control system concerning this invention, and a 2 tank type oil circulation thermostat. It is an example of the operation | movement model of a 2 tank type oil circulation thermostat. It is a graph which shows the simulation result of the operation model of a 2 tank type oil circulation thermostat. It is another graph which shows the simulation result of the operation | movement model of a 2 tank type oil circulation thermostat. It is another graph which shows the simulation result of the operation | movement model of a 2 tank type oil circulation thermostat.

Explanation of symbols

1: Measurement control system 11: Measurement unit 12: AD converter 13: DA converter 14: I / O circuit 15: Memory 16: Control unit 17: Analysis unit 18: Arithmetic processing unit 19: Display unit 20: Model creation unit 21: Model component storage unit 22: Simulation code generator 23: Control code generator 24: Operation input unit 25: Simulation unit 26: Switch 27: Heater control circuit 28: AD converter control circuit 29: Comparator 3 : Control target system 31: Inner oil tank 32: Outer oil tank 33: Inner oil tank oil source 34, 36, 43, 47: Heater 35: Outer oil tank oil source 37, 38: Pump 39, 40: Pipe 41: Temperature sensor 45: Water tank 49: Heater drive circuit

Claims (5)

A model creation unit that creates a theoretical behavior model and a control behavior model related to the controlled object, a function that acquires an effective factor related to the controlled object as an input signal, and outputs a control signal to the controlled object corresponding to the input signal A measurement control system including a measurement unit having a function, a simulation unit that performs a simulation experiment of the theoretical behavior model, and a control unit that controls the measurement unit,
The theoretical behavior model is obtained by expressing a physicochemical phenomenon that occurs in the controlled object by a mathematical formula, and replacing individual arithmetic processing included in the mathematical formula with individual model components,
The control behavior model is created so as to have a predetermined relationship such as an equivalent relationship with the theoretical behavior model based on a simulation experiment result of the theoretical behavior model, and the function of the measurement unit is controlled in the theoretical behavior model. A measurement control system characterized by being obtained by substituting for a control operation of a part. The measurement control system includes:
A simulation code generator for generating a simulation code for the simulation unit to perform a simulation based on the created theoretical behavior model;
A control code generator for generating a control code for the control unit to control the measurement unit based on the created control operation model;
The measurement control system according to claim 1, comprising: The measurement control system includes:
An analysis unit that selects any two signals from a plurality of signals input to the measurement unit and analyzes the presence or absence of a predetermined relationship such as a correlation between the two signals;
The measurement control system according to claim 1, wherein the model creation unit reflects the analysis result of the analysis unit in the creation of the motion model. The model creation unit
The measurement control system according to claim 3, wherein an analysis result of the analysis unit is reflected in determination of the input / output signal or determination of a parameter of the model component. The measurement control system includes:
The display device displays any one of an operation model created by the model creation unit, a simulation experiment result of the simulation unit, a control result of the control unit, and an analysis result of the analysis unit. The measurement control system according to claim 4.

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