基于Java的PLC计算机仿真

为了实现PLC（可编程控制器，Programmable Logic Controller）的计算机仿真，提出基于Java语言的五层仿真模型。该模型将仿真系统分为图形界面，用户操作响应与仿真运行，元件位置存储，元件信息存储，模拟地址空间五个功能层。模型包含不同功能层之间的信息存取关系和存取规则。提供跨操作系统运行，面向对象的元件封装，梯形图扫描，仿真运行与用户响应同步等要点和难点的解决方案。

Computer Simulation of PLC Based on Java

To realize the computer simulation of PLC, a five-level simulative model was constructed. The model divided the simulative system into five functional levels: the graphical level, the operational response and simulative run-time level, the component position storage level, the components ' information storage level and the simulative address space level. The interactive relation between different levels and the rules of the interaction were also provided in the model. Moreover, some main points and corresponding solutions in the realization of the software such as to operate across different operating systems, object-oriented encapsulation of PLC components, the scanning process of the ladder diagram, the simultaneity of simulative running and operational response were also provided.