A Controller Design Based On A Simple But Optimal Electrical Control System

By virtue of its powerful control functions and high reliability, easydebugging, easy repair, Programmable Logic Controller (PLC) plays a leadingrole in modern industrial present control. Though various kinds of micro-PLCapplied to simple control are constantly emerging with more emphasis on thesimple control system, they are too cumbersome in design; besides,cost-effective also less than the relay contactor control; the last, the complicatedoperation and to program language are often headaches for general electricians.At present, the relay contactor control model is also the main stream for thesimple control system (such as, multi-motor sequence start, automatic two-speedmotor, etc.) in industrial present control. However, relay contactor controlsystem inevitable have the following defects: high fault rate, poor reliability,serious waste of resources, bulky control device, and unchangeable controlcircuit. For the above reasons, it has a bright future of application by developingsimple, economical, practical and flexible new control device to replace thetraditional one.Development of a new type of controller is based on this idea in this thesis.This controller will make up the defects of traditional relay control system, forinstance, high fault rate, irresponsibility, short-lived nature. In other words, thecontroller can not only improve the security of the control system but alsoreduce the giant waste by PLC technique. On the other hand, the controller hasless number of control components and requires less space without any changeof traditional mode, namely, without increasing any hardness of technique andthe introduction of new technique tends to drive the general electricians to enterinto the stage of intelligent stage and information stage. Hence, they cangradually acquire new knowledge, which is conducive to the development ofmodern industry control. What is discussed in this thesis is how to optimize the simple controlcircuit, where the advantages and disadvantages of different controllers areanalyzed first and then a concrete design scheme is proposed according to therequirement. The scheme is briefly described as follows: we combine functionsof the middle of the relay, time relay, over-current over-voltage relays, voltagerelays, etc. together, with the microprocessor technology as the core, toarbitrarily choose correspondence between input and output, fixing on thedelayed models and delayed time, adjusting the value of current and voltagewhich is needed, etc. in other words, we make use of the advantages ofprogrammable controllers to enhance the value of traditional relay contactorcontrol system. And then we explore the rationality and feasibility throughcomparative analysis of the actual control system circuit to study itsoptimization features, and also present a detailed analysis of the scheme ofmulti-functional controller using Atmega32microprocessor.