Masaya Tanuma

Interactive Simulator Using a Graphic Terminal for Linear Control System

Abstract Cost and time needed for dynamic simulation of control systems increase very rapidly as controlled process become larger in scale and more complicated. In order to conduct process simulation efficiently, an interactive simulator using a big computer was developed. In the system, engineer can enter data about the controller, described by block diagrams in the simulator, thorough an intelligent terminal interactivelly. The block diagram is displayed on a strage type CRT (Cathode Ray Tube) immediately. With respect to analysis, time response, frequency response and root locations can be calculated and the results are displayed on CRT

Interactive Simulation Method Using Tableau Approach for Nonlinear Control System

Abstract In order to design control systems and simulate processes efficiently, an interactive simulation system using a mainframe computer is newly developed. This system allows the nonlinear block diagrams used widely by control engineers to be entered in the host computer interactively through an intelligent terminal. As simulation method for a nonlinear control system, the tableau approach, a high speed calculation technique for electronic circuit, is employed. One of the advantages of the tableau method is that this method allows larger step than conventional techniques. This is confirmed in a case study.

Multivariable Control of a Five-Stand Cold Mill

The design method of multivariable control system for a 5-stand cold mill is developed using optimal control theory. The control objective in a cold mill is to reduce deviations of strip thickness and interstand tension. Thickness and tension of strip are controlled by adjusting screw down position and roll velocity. These output variables and manipulating variables are related by several nonlinear differential equations containing variable time-delays.

An Interactive Simulation System for Analysis and Synthesis of Digital Control Systems

Abstract In order to conduct efficient simulations and designs of digital control sysems, an interactive simulation system which can treat a hybrid system, i.e. a discrete-continuous time system is developed. This system consists of an interactive block diagram input function and analysis functions. The former introduces the concept of a structured block diagram, i.e. a set of block diagrams organized hierarchically to describe a complex system. By applying several techniques appropriate for computing a discrete-continuous time system, interactive analysis functions for the structllred block diagrams are realized. These functions can compute time responses, frequency responses and root locations of nonlinear digital control systems as well as linear systems, and display the computed results on a CRT.

A Graph Oriented Approach to Analysis of Nonlinear Block Diagram

Abstract In the basic design of power boiler, precise dynamic simulation using a high-order model is required. For stable computation of stiff boiler model covering both quick and slow dynamics, a graph oriented approach to analyzing nonlinear block diagram is developed. Since this method can generate the minimum order computational model from complicated block diagrams by simple procedure, stable dynamic simulation using an implicit formula can be put to practical use. It can also produce computational models for steady state analysis and generation of linear state model in same scheme. Simulations of a one-through sliding pressure boiler using high-order model, confirm validity of this method.