Study And Application Of DDC And PLC Technology In Electric System Improvement Of Machine Tools

Equipments are the material and technological foundation of technology development and achievement of operational objectives. The technical performance of equipments and technological status directly affect the business situation of product quality, energy materials consumption and economic benefits. Sichuan changjiang crane Co. Ltd is a production base with more than 40 years'history, whose equipments are dated, of high breakdown rate, of high maintennance difficulty and long maintenance cycle, which has affected the manufacturing schedule seriously and has become one of the big bottlenecks of the corporation.To resolve the questions, this paper adopted the PLC(programmable Controller, PLC) and DDC(Digital Direct Converter, DDC) technologies to improve the electrical system of the heavy machines so as to increase the stability of the process, to simplify the maintenance, and to achieve the effect of lowering costs.The main contents as follows:Firstly, it analyzed the domestic and overseas application and study status quo of PLC and DDC technology and pointed out the significance of apply programmable control technology and fully DDC technology to improve the the heavy machine electrical system in the factory.Secondly, it analyzed and studied the basic components of the PLC, working theory and the basic principles for programmable control system design, and the general steps, the DDC principles, methods, features, structure, working principle of fully digital DDC converter the system, and summarized the application attention of the two technologies.Finally, on the basis of research on the PLC and DDC technology, this thesis mainly went along the application research on using the two rechnologies on heavy machine tool plants to improve their electrical system, including selection of equipments, schematics and wiring pattern design, programe design, assembly and application effect analysis.