JPH01133101A - Multi-variable control device - Google Patents

Abstract

PURPOSE:To attain rapid processing of multi-variable control by allowing a multi-variable control means to execute operation based on a control signal and measured values obtained from plural controlled systems to form operation signals for the controlled systems and transferring data between the multi- variable control means and I/O means. CONSTITUTION:The specifications of a product and control parameters are applied from a computer 6 to a control device 1 through a network 8 and stored in vector process units (VPUs) 21. At the time of starting rolling, a DDC controller 20 in the control device 1-1 applies the states of respective stands 5 to the VPUs 21 as reading state variables through a linkage interface circuit 23. Respective VPUs 21 compute the matrix products of the state variables and output the optimum manipulated variables of respective stands 5 to the control device 1-2 through a linkage device 22 and the control device 1-2 converts the inputs to real manipulated variables and outputs the converted variables to respective PI/Os2 through the interface device 23 to drive the stands 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multivariable control device, and particularly to a multivariable control device suitable for control that requires high-speed processing such as rolling.

[Conventional technology]

The conventional device had a configuration as shown in FIG. This figure shows the case of rolling control as an example.

The steel material 7 successively passes through a plurality of rolling mills (stands) 5 and is rolled during the process. In order to control rolling for each stand 5, it has a dedicated PI 102 and process control device 1.
Each process control device 1 was controlling the passing steel material 7 in real time in order to achieve the rolling specifications instructed by the process computer 6 connected through the network 8 at the initial stage of rolling. However, although it can be easily assumed that the control performed by a stand on continuously passing steel materials affects the control of other stands, especially adjacent stands, the process control device 1 has only real-time processing capacity for one stand. However, if we consider control that takes into account the state of each stand 5, the computing power of (stand) 2 would be required, which could not be realized.

As described above, since conventional control does not take into account the influence between stands, there is a limit to the accuracy improvement for high-speed rolling.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology has a problem in that real-time control cannot be performed in consideration of the influence of control of one stand on other stands because there is no means for high-speed data transfer between process control devices.

Furthermore, when multivariable control is applied, there is a problem in that a large amount of matrix multiplication operations cannot be processed at high speed as the number of state variables increases.

An object of the present invention is to provide a multi-variable system that can process multi-variable control based on state variables from each controlled object at high speed by increasing the calculation speed of multi-variable calculations and speeding up data transfer between each control device. The purpose is to provide a control device.

[Means for solving problems]

The above problem is caused by a control means provided in each of the control objects that generates an operation signal based on a control signal set from the upper control means and measurement signals input from a plurality of control objects; and input/output means for transmitting and receiving signals to and from the controlled object, wherein the control means performs multivariable calculations based on the control signal and the measurement signal of each of the controlled objects, and performs multivariate calculations on each of the controlled objects. Solved by a multi-variable control device characterized in that it is provided with a multi-variable control means for generating the operation signal, and a communication means for connecting the multi-variable control means and the input/output means through a communication line to transfer data. be done.

[Effect]

In a control device that inputs a control signal from a higher-level control means and a measurement signal from a plurality of control objects and outputs an operation signal to each control object, the control signal and the measurement signal of each of the control objects are input. Based on this, the multivariable control means performs multivariable calculations, generates the operation signal for each of the control objects, and transmits this operation signal and the measurement signal to the communication means to perform the multivariable control. Data is transferred between the means and the input/output means.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a diagram showing the overall configuration of this embodiment, and shows a case where multivariable control is applied to a rolling control system consisting of four rolling mills.

The PI/○ (input/output means) 2 outputs a control signal 24 for the rolling mill (stand) 5 to the driver 3, and the driver 3 outputs a drive signal 25 to the stand 5. Further, the state quantity 26 of the stand 5 is inputted to the sensor 4 and inputted as a state signal 27 to Pr2O3. The plurality of process control devices 1 input the status of the stand 5 from each PI 102, calculate appropriate process operation instructions to achieve product specifications, and output them to the corresponding PI 102.

The plurality of process control devices 1 and Pr2O3 are connected to a linkage device (communication means) 22 that performs data transfer at high speed. This linkage device 22 is a softwareless transfer device, and is capable of cyclically supplying all data of each PI 102 to a plurality of process control devices 1 connected to this linkage device 22 and updating the data. moreover,
The linkage device 22 can cyclically supply the control data held by the process control device 1 to other process control devices 1 as well as the Pr2O3 data, and can update the data. In each process control device 1,
The linkage interface group @23 holds all the data of the devices connected to the linkage device 22, and the Direct Digital C in the process control device 1.
ontrol (DDC) The data can be read and written from the controller 20 at any time.

The plurality of process control devices 1 are each connected to an upper level network 8, and receive product specification instructions from a process computer (upper level control means) 6 connected to this network 8,
Receive calculation parameters and transmit rolling information. In the process control device 1 in this embodiment, a configuration example in which the rolling control system is divided into two functional units is shown.

Each process control device 1 employs a digital signal processing device, and a V
ector Processing Unit (V
A plurality of PU) 21 (multivariable control means) are linked to the DDC controller 20 via a bus 28, and the VPU 21 is made into a coprocessor so that it can operate in parallel.

Next, the operation of this embodiment will be explained. The product specifications and control parameters sent from the host process computer 6 via the network 8 are input to each process control device 1.
After being converted to the parameters of VPU21, each VPU21
is memorized. When rolling starts, the process control device 1
The DDC controller 2o in -1 reads the status of each stand 5 via the PI 102 and the linkage device 22 using the linkage interface device 23, and provides it to the VPU 21 as a state variable.

The VPU 21 is prepared for each stand 5, and utilizes the coprocessor function to calculate the optimum operation amount of each stand 5 and the matrix product with the state variable by simultaneous calculation.

This calculated optimum operation amount is taken into the process control device Wi1-2 via the linkage device 22, and is transferred to each PI102.
A matrix multiplication operation is performed to convert the operation amount into an actual operation amount to be output to the PI 102, and the operation amount after this operation is output to each PI 102 via the linkage interface device 23 to drive the stand 5.

This embodiment has the following effects compared to the conventional example shown in FIG.

Process control device 1 and PI 1 by linkage device 22
Since the data transfer between 02 and 02 can be performed cyclically without software, the speed can be increased by about 7 times compared to the conventional example using an upper network without linkage device 22.

In addition, by adopting a digital signal processing device, it is possible to speed up the matrix multiplication operation peculiar to multivariable control, and by using a coprocessor so that the operation can be continued independently, it is approximately 15 times faster than the conventional example. This results in faster speeds.

Furthermore, since functions can be easily distributed by dividing into control system units, system design is simplified, and system expansion is easy and flexible.

The cost for the device alone is also reduced to 1/3 compared to the conventional example.

Although the above embodiments have shown examples in which multivariable control is applied to rolling control, it can be similarly applied to controls other than rolling.

〔Effect of the invention〕

According to the present invention, in the control device that inputs a control signal from a host control means and measurement signals from a plurality of control objects and outputs an operation signal to each of the control objects, the control device outputs an operation signal to each of the control objects. The multi-variable control means performs multi-variable calculations based on the measurement signal, generates the operation signal for each of the controlled objects, and communicates the operation signal and the measurement signal to the multi-variable control means and the input/output means through the communication means. There is an excellent effect that multivariable control based on state variables from the control target can be processed at high speed by transferring data between the control target and the control target.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention, and FIG. 2 is an overall configuration diagram of a conventional example. 1... Process control device, 2... PIlo, 6...
・Process computer, 8...Network, 20...
DDC controller, 21... Vector process unit, 22... Linkage device, 23... Linkage interface device.

Claims (1)

[Scope of Claims] 1. Control means provided in each of the control objects that generates an operation signal based on a control signal set from a higher-level control means and measurement signals input from a plurality of control objects; In a control device having input/output means for transmitting and receiving signals between a control means and the controlled object, the control means performs multivariable calculations based on the control signal and the measurement signal of each of the controlled objects. communication means for connecting the multivariable control means and the input/output means via a communication line to transfer data;
A multivariable control device characterized by being provided with. 2. The device according to claim 1, wherein the multivariable operation is a matrix multiplication operation.