PLC控制并联电梯的程序设计.doc

哈尔滨工业大学工学硕士学位论文 哈尔滨理工大学学士学位论文 - PAGE II - - PAGE II - PLC控制并联电梯的程序设计 摘要 电梯是高层建筑必不可少的交通工具。在规模较大的建筑内常常安装两台或两台以上的电梯。为了提高电梯的运行效率，两台电梯通常采用并联控制，两台以上的电梯则采用群控。 在两台电梯的并联控制中，并联调度算法是整个控制系统的核心。调度算法的合理性与否直接影响到电梯运行效率的高低。在分析电梯集选控制功能的基础上，设计两台PLC和两台变频器组成的11层电梯的并联控制系统，给出系统组成框图，编写电梯并联控制程序，并详细阐述该系统的并联功能和软件的设计方法。 两台PLC并联控制系统之间采用欧姆龙的CQM1H型PLC 进行1：1链接通信交换信息，共享厅外召唤信号、层楼信号和运行方向信号，实现两部电梯的并联调度控制。控制程序根据两台电梯的运行状态、运行方向、轿厢与呼梯信号的位置，来决定由哪台电梯响应呼梯信号。 采用了PLC串行通讯的方法, 构成双PLC的控制系统, 实现了两部电梯的并联调度控制, 并采用厅外呼梯信号单梯采样双梯共享的技术, 节省了硬件资源, 降低了系统成本。 关键词　并联控制；电梯；可编程序控制器；调度原则；控制算法 Research of the Elevators Parallel Control Abstract Elevators are indispensable vertical traffic transport in the high buildings. There are always two or more than two elevators in a large scale building. In order to improve the efficiency of the elevators，parallel control is always used in double elevator，and group control is used in more than two elevators. Dispatch algorithm is the center of the system in the elevators parallel control. The rationality of the dispatch algorithm influences the efficiency of the elevators. Based on the analyses of the collective selective control function of elevators，a parallel control system was given in this paper. The 1-layers-elevators parallel control system was composed of two PLC s and two invertors. The system structure and the parallel control programmer were given. The parallel control function， design methods of hardware and software of this system were introduced. The l：1 PLC-LINK communication system of OMRON was used between two PLC s. By means of the serial communication，the outer calling signals， the position signals and the direction signals were shared by the two elevators， and the parallel control was realized. According to the perform status，the direction of two elevators，the position of the elevator ears and the outer calling signals， a judge was made by the control programmer that which one elevator to respond the outer calling signals. A PLC parallel control