JP3004029B2 - Production quantity analysis system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a production state quantity analysis system for predicting a production amount and a quality prediction of a production facility.

[Related Art] Conventionally, there has been proposed a production state quantity analysis system for predicting a production result by formulating the capacity of a production facility in advance (also called simulation). An equation for predicting a production result used in the production state quantity analysis system is represented by the following equation.

P = f (s, c) (1) Here, P is an output state quantity, and each output element representing the production quantity and the quality of the produced product, for example, weight,
It is represented by a matrix such as the color and the number of defective products.

s is an input state quantity, which is represented by a matrix of input elements of raw materials supplied to the production equipment, for example, input elements such as weight, components, and temperature.

c is a process state quantity, which indicates a production processing state in the production process, and is represented by a matrix of each process element such as an additive and operating conditions.

 f means a function.

When the production is started, the production state quantity analysis system performs a statistical analysis using the data indicating the input state quantity described above, the process state quantity corresponding to the time when the data is input, and the data indicating the actually measured output state quantity. And the above function f
(S, c) is calculated automatically. Specifically, the function f (s, c)
Is expressed by f (s, c) = A × C + B × S (2), and the values of the constants A and B are determined.

By substituting the input state quantity and the process state quantity into the arithmetic expression thus determined, and calculating the output state quantity,
Predict output state quantities. Diagnosis processing of the cause of the abnormality is also performed using the output state quantity prediction function.

In other words, when a quality defect occurs in the product obtained as a production result, the facility operator prints each element data of the input state quantity, the process state quantity, and the actually measured output state quantity accumulated and stored in the production quantity state analysis system. The output and the print result are referred to, and the elements of the input state or the process state considered to be the cause of the abnormality are retrieved and extracted based on past experience.
Next, the data on the searched and extracted element is changed, and the output state quantity of the element having the abnormality is calculated by the production state quantity analysis system using the changed data. When the calculation result becomes normal, it is determined that the searched and extracted element is the cause of the abnormality.

[Problems to be solved by the invention] However, in the conventional production state quantity analysis system,
As the data of the input state quantity and the process state quantity increases, the equipment operator refers to more data when performing the abnormality diagnosis. In addition, the calculation of the output state quantity must be performed by trial and error in order to search for the element of the cause of the abnormality. As a result, the conventional system has a problem that it takes time to analyze the cause of the abnormality.

Therefore, the applicant of the present application has proposed a production state quantity analysis system in which an output element is specified, and an input element or a process element that affects the specified output element is searched and extracted, thereby shortening the time required for the analysis processing of the cause of the abnormality. (Filed on October 2, Heisei 1).

However, in the above proposal, there is still a point to be improved in that it is not possible to manage process elements that are difficult to measure or control on-line due to environmental conditions and technical constraints.

In view of the above, an object of the present invention is to provide a production state quantity analysis system capable of analyzing a state quantity that is difficult to measure online or an intermediate product that is difficult to control online.

[Means for Solving the Problems] In order to achieve such an object, the invention according to claim 1 measures actual state quantities of input elements, process elements, and output elements in a production facility, and determines the actual measured state. A production state quantity analysis system for analyzing a production state by automatically creating a second arithmetic expression representing the relationship between the state quantity of the output element, the state quantity of the input element, and the state quantity of the process element based on the quantity. A first operation for estimating a state quantity of a process element that is directly difficult to control or a process element that is difficult to measure directly online from a state quantity of an input element and / or a process element that can be measured. A first arithmetic processing means for determining an equation in advance and calculating a state quantity of a process element difficult to control or a process element difficult to measure online by the first arithmetic expression; The second operation including the difficult-to-control process elements or the on-line difficult-to-measure process elements using the state quantities of the difficult-to-control process elements or the on-line difficult-to-measure process elements. And a second arithmetic processing means for automatically creating an expression.

The invention according to claim 2 is characterized in that a threshold value for warning is set in advance for the state quantity of the process element that is difficult to control directly or that is difficult to measure directly online.
Comparing means for comparing the state quantity of the directly difficult-to-control process element or the on-line directly difficult-to-measure process element calculated by the arithmetic processing means with the threshold value;
And a warning means for giving a warning when the determination result of the comparison means exceeds the threshold value.

[Operation] The present invention calculates a state quantity that is difficult to control directly or is difficult to measure directly online using a predetermined first arithmetic expression by using a state quantity obtained by a conventional analysis. . By treating the calculated state quantity as an apparent actually measured value, a process element that is difficult to directly control or that cannot be directly measured online can be included in the second arithmetic expression for calculating the output state. In addition, by comparing the apparent measured value calculated by the first arithmetic expression with the threshold value, it is possible to manage a process element that is difficult to directly control or that cannot be directly measured online, which has not been conventionally possible. It becomes possible.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

 FIG. 1 shows a basic configuration of an embodiment of the present invention.

The production state quantity analysis system in the present embodiment measures each state quantity of an input element, a process element, and an output element in a production facility, and, based on the actually measured state quantity, the state quantity of the output element and the state of the input element. This is a production state quantity analysis system for analyzing a production state by automatically creating a second arithmetic expression representing a relationship between the quantity and the state quantity of the process element.

In FIG. 1, reference numeral 100 designates a first arithmetic expression for calculating a state quantity of a process element that is difficult to control or a process element that is difficult to measure online from an input element and / or a state quantity of a process element that can be measured, The first arithmetic processing means calculates the state quantity of the process element that is difficult to control or that is difficult to measure online using the first arithmetic expression.

Reference numeral 200 denotes a state quantity of the process element difficult to control or the process element difficult to measure online calculated by the first arithmetic processing means as an apparent actual measurement state quantity, and the process element difficult to control or the actual measurement online. The second arithmetic processing means automatically creates the second arithmetic expression including a difficult process element.

Reference numeral 300 designates a threshold value for warning the state quantity of the process element that is difficult to control or the process element that is difficult to measure online, and the process element that is difficult to control or that is difficult to measure online calculated by the first arithmetic processing means. This is a comparing means for comparing and determining the state quantities of the various process elements with the threshold.

Reference numeral 400 denotes a warning unit that gives a warning when the determination result of the comparison unit exceeds the threshold value.

 FIG. 2 shows a specific circuit configuration of the embodiment of the present invention.

In FIG. 2, a computer 1, a disk storage device 2,
A keyboard input device 3, a display device 4, a printing device 5, and an input / output interface 6 are connected to a common bus 7.

The computer 1 controls the operation of the entire production state analysis system, and automatically performs a production state expression relating to the present invention, and also predicts an output state quantity and performs a fault diagnosis process, which has been conventionally performed.

The disk storage device 2 stores data indicating the input state quantity, the process state quantity, and the actually measured output state quantity input from the production facility 20 via the keyboard 3 and / or the input / output interface 6 on a disk for each element item. .

The display device 4 is used when displaying the prediction result of the output state quantity and the abnormality diagnosis result calculated by the computer 1. The printing device 5 is used to print out data such as input state quantities, process state quantities, and measured output state quantities stored in the disk storage device 2.

FIG. 3 shows an address configuration of a data storage area of each state quantity of the disk of the disk storage device 2.

The memory address is configured to store input data at each data input time, and a data storage area is determined for each element.

FIG. 4 shows the address configuration of the storage area of the prediction data of the output state quantity of the disk of the disk storage device 2.

The storage area is defined such that the memory address stores the time information when the data of the input state quantity is input and the predicted data of the output state quantity when the raw material input at that time is output as a product in association with each other. Have been.

Next, the output state quantity Y (t) of the present invention is converted to the process state quantity X.
(T) and an arithmetic expression (second arithmetic expression) calculated from the input state quantity U (t) will be described.

That is, the output state quantity Y (t) is generally obtained by the following equation.

Y (t) = AX (t) + BU (t) (2) In the above _{formula, y 1 (t) ~y n} (t) is the output state quantity Y
These are the level values of 1 to n (positive integer) elements (output elements) constituting (t), and represent the actual measured values of the output elements for the raw material input at time t.

x ₁ (t) to x _m (t) are level values indicating the states of _{1 to m} (positive integer) elements (process elements) constituting the process state quantity X (t), and are input at time t. Represents the state of the process element added to the raw material. These include process elements that are difficult to measure online or difficult to control (set) as process elements related to the present invention.
For example, it is difficult to measure the concentration of a specific by-product ion, which is unrelated to the product contained in the solution in the spinning process, online, so that the ion concentration of the by-product is a process element that is difficult to control. Can be considered.

 u₁(T) to u (t) Constitutes the process state quantity U (t).
1 to (positive integer) of the raw materials input at time t
This is a level value indicating the state of the element (input element).

 A and B are constants determined from measured output state quantities.
Constant A is a combination of n output elements and m process elements
Each count a₁₁~ A_nmIs represented by the following matrix. Constant B
Is determined by the combination of n output elements and l input elements.
Each count b₁₁b_n Is represented by the following matrix.

It is assumed that, for example, the following output state formula is obtained as a sub-expression in the above determinant.

y_{i (t)}= A_i1x_{1 (t)}+ A_i2x_{2 (t)}+ ... + a_ipx_{p (t)} + ... + a_imx_{m (t)}+ B_i1u_{1 (t)}+ B_i2u_{2 (t)} + ... + b_i u _(t) … (8) At this time, x_{p (t)}Are difficult to measure online
It is a state quantity of a difficult process element. This state quantity is
The relationship between the process state quantity and the input state quantity is given by the following equation (9).
More predetermined.

_{x p (t) = c q} x q (t) + d r u r (t) ... (9) x q (t), u r (t) is the control state quantity, c _q, d _r is the coefficient .

Therefore, (9) (Expression corresponds to the first arithmetic expression of the present invention, and the actual measured values x _{q (t)} and ur _(t) are substituted into the expression (9), and the apparent actual measured value x _{p (t)} is calculated. Further, the measured values x _p apparent in this embodiment _(t), it is compared with the predetermined abnormality detection threshold value. apparent measured values x _{p (t)} is When the threshold value is exceeded, a warning is output to the display device 4 and the printing device 5.

The determinant for calculating the output state quantity includes (8)
Expression (10) obtained by substituting expression (9) into the expression is used. Expression (10) corresponds to the second operation expression of the present invention.

y_{i (t)}= A_i1x_{1 (t)}+ A_i2x_{2 (t)}+ ... + c_qx_{q (t)}+ D_ru_{r (t)} + ... + a_imx + b_i1u_{1 (t)}+ B_i2u_{2 (t)} + ... + b_iu _(t) … Of the state variables used in equation (10) or (8)
Difficult state quantity x_{q (t)}Is used in equation (9) instead of
Controllable state x_{q (t)}, u_{r (t)}Using the
Recalculate the output state equation (11) by calculating the coefficient of state quantity,
Is also good.

y_{i (t)}= E_i1x_{1 (t)}+ E_i2x_{2 (t)}+ ... + e_iqx_{q (t)} + E_iru_{r (t)}… + E_imx_m+ F_i1u_{i1 (t)}+ F_i2u_{2 (t)} + ... + f_i u_(T) …… (11) (e_im, f_i Is a newly obtained coefficient) The output status related to the present invention
The process of creating a formula will be described. In addition, FIG.
Input, process, and output requirements for the entire manufacturing process and each process
An example of a prime is shown. This example uses a small number of elements for explanation.
However, there are many factors for actual system operation.
Is provided.

For example, the production state equations from the first step to the third step are as follows.

f ₁ → ₃ = A (1,3) X (t) + B (1,3) U (t) In this example, a control program for calculating the coefficients A and B is built in the computer 1, and by executing each control program to calculate the coefficients A and B, an output state equation (second arithmetic equation) f Create ₁ → ₃ . The operation of the circuit shown in FIG. 2 will be described below with reference to the flowchart shown in FIG.

In FIG. 2, when actual measurement data on input, process, and output elements is input from the production facility 20 and the keyboard input device 3 at regular intervals, the computer 1 stores the data in the disk storage device 2 as shown in FIG. The measured data is stored. In addition, the state quantity of an element that is difficult to control or measure is calculated and stored in the disk storage device 2 as an apparent measured value.

At this time, the computer 1 operates as a first arithmetic processing unit. Next, the computer 1 calculates the coefficient of the output state equation,
A and B are calculated based on the actual measurement data (including the apparent actual measurement data) (steps S10 → S30 in FIG. 7).

Subsequently, the computer 1 substitutes a new value actually measured online using the output state formula specified using the calculated values of the coefficients A and B, thereby obtaining the input process state at the apprentice time t. Then, an expected output predicted state quantity is calculated.

Next, the computer 1 executes a monitoring process for comparing the calculated output predicted state quantity with a specified value for each element to check for an abnormality.

If an abnormality is detected in the analysis processing, the output state formula is changed to diagnose the cause of the abnormality.

For this purpose, after correcting the operating conditions and the input conditions, the production state is predicted under the new conditions (step S40 in FIG. 7).

The computer 1 also compares threshold values of process elements that are difficult to control or measure, and checks for abnormalities (step S50 in FIG. 7). At this time, the computer 1 operates as comparison means.

When an abnormality is detected, a warning message is displayed on the display means by the computer 1 (step S60 in FIG. 7). In this case, the display means operates as a warning means.

The above procedure is repeatedly executed at regular intervals to predict the output state quantity with respect to the input state quantity and monitor the operating conditions.

 The following examples are given in addition to this embodiment.

1) In the present embodiment, only the presence / absence of an abnormality is checked for a process element that is difficult to control or measure, but an equation for calculating a state quantity of a process element that is difficult to measure or control online or by using:
The state quantity may be predicted.

[Effects of the Invention] As described above, according to the present invention, it is possible to include a process element that is directly difficult to control or difficult to measure in an arithmetic expression for calculating an output state quantity. The prediction accuracy of the output state quantity increases.

In addition, since it is possible to directly grasp the state quantity itself that is difficult to control or difficult to measure, it is not necessary to install a measuring device in a place with a bad environment, and it is possible to enhance the safety of the facility operator.

[Brief description of the drawings]

1 is a block diagram showing a basic configuration of an embodiment of the present invention, FIG. 2 is a block diagram showing a specific circuit configuration of the embodiment of the present invention, and FIGS. 3 and 4 are disk storages of the embodiment of the present invention. 5 and 6 are explanatory diagrams showing a production state of the embodiment of the present invention, and FIG. 7 is a control procedure executed by the computer 1 of the embodiment of the present invention. It is a flowchart shown. 1 ... computer, 2 ... disk storage device, 3 ... keyboard, 4 ... display device, 5 ... printing device, 20 ... production equipment.

Continuation of the front page (72) Inventor Kazuki Baba 1-3-1 Yoko, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside Asahi Engineering Co., Ltd. (56) References JP-A-2-71961 (JP, A) Japanese Utility Model Showa 57 −42404 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) B23Q 41/00 B23Q 41/08 G06F 19/00

Claims (2)

(57) [Claims] 1. A state quantity of an input element, a process element, and an output element in a production facility is actually measured, and the state quantity of the output element, the state quantity of the input element, and the state quantity of the process element are measured based on the actually measured state quantity. The second representing the relationship with the state quantity
This is a production state quantity analysis system that analyzes the production state by automatically creating arithmetic expressions, and measures the state quantities of process elements that are difficult to control directly or that are difficult to measure directly online. A first arithmetic expression for estimating from a possible input element and / or a state quantity of a process element is determined in advance, and the state quantity of a process element that is difficult to control or that is difficult to measure online is calculated by the first arithmetic equation. A first arithmetic processing unit, and a process element that is difficult to control calculated by the first arithmetic processing unit or a state quantity of a process element that is difficult to measure online is used as an apparent actually measured state quantity. A second operation processing means for automatically creating the second operation expression including a process element or a process element which is difficult to measure online. . 2. The method according to claim 1, wherein a threshold value for warning is set in advance for a state quantity of the process element which is difficult to directly control or which is difficult to measure directly online. Comparing means for comparing the state quantity of the process element which is directly difficult to control or the process element which is difficult to measure directly online with the threshold value, and that the determination result of the comparison means exceeds the threshold value 2. The production state quantity analysis system according to claim 1, further comprising a warning means for giving a warning when indicated.