[理学]毕业设计-电子选层器在电梯控制上的应用.doc

毕业设计（论文） 电子选层器在电梯控制上的应用 姓 名 学 院 专 业 指导教师 完成日期 电子选层器在电梯控制上的应用 摘 要 随着现代科学技术的迅猛发展，电梯中的选层器也带来了新的革命。电子选层器在当今目前大多数变压变频电梯中较为常见。它正以它的优点：维修方便、精度较高和可靠性高，逐步取代电气选层器和机械选层器。 所谓电子选层器，实际上就是利用旋转编码器得到的脉冲数来计算楼层的装置。这在目前大多数变频电梯中较为常见。 在电梯控制系统中，电气选层器与机械选层器一样，应具有下列功能： 反映电梯在井道内的某一瞬间时的位置，并用信号灯显示。 在应答每一个层站的内、外呼梯信号时，自动发出电梯制动减速的信号。 在电梯应答某一层站的内、外呼梯信号后，自动取消某一层站的呼梯记忆信号。 而对于各层的厅外呼梯信号仅消除与电梯运行方向一致的信号或最远的反向呼梯信号。 4、电气上的端站保护功能，包括端站自动发出减速信号和端站的方向限位保护。 原理： 装在电动机尾端上的旋转编码器，跟着电动机同步旋转，电动机每转一转，旋转编码器能发出一定数量的脉冲数（一般为512或1024个）。 经过变频器的脉冲衰减后再送入PLC的高速计数输入端，通过比较输入的两相脉冲的超前与滞后，来判断增计数器是增计数或减计数。在电梯安装完成后，一般要进行一次楼层高度的写入工作，这个步聚就是预先把每个楼层的高度脉冲数和减速距离脉冲数存入电脑内，在以后运行中，旋转编码器的运行脉冲数再与存入的数据进行对比，从而计算出电梯所在的位置。 目前电子选层器比电气和机械选层器使用更广泛，主要有以下几个特点： 安装于电动机轴上，维修方便； 精度较高； 结构简单，可靠性高。 关键词：电子选层器、变压变频电梯、电气选层器、机械选层器 目 录 第一章 绪 论·····························································1 1.1 选层器的功能···················································1 1.2 机械选层器·····················································1 1.3 电气选层器·····················································2 1.4 电子选层器·····················································2 第二章 脉冲采集方法及 PLC软继电器的功能说明·······························4 2.1. 旋转编码器·····················································4 2.2. 高速计数器·····················································5 2.2.1.. 1相型·····················································6 2.2.2 ..2相双相计数器·············································7 2.2.3 ..2相A-B.相计数器···········································7 2.2.4..最高计数频率···············································8 第三章 电梯I/O分配表及继电器M表·········································10 3.1 电梯I/O分配表·················································10 3.2 继电器M表····················································11 第四章 程序编制···························································15 4.1 电梯各楼层预置脉冲数设置·······································15 4.1.1 电梯各楼