求翻译：本文首先阐述了选题的目的和意义,电梯的概论，包括电梯的起源与发展、结构、控制要求等；又分析了继电器控制的电梯控制系统和PLC控制电梯系统的特点。然后本文进行了硬件设计，首先分别介绍PLC和变频器的相关知识，然后根据设计的要求分别选择了合适的PLC和变频器，在此基础上又分别PLC控制系统硬件设计和变频调速的硬件设计，最后是控制系统的硬件设计。软件设计是在硬件设计的基础上进行，本文几乎包括所有的PLC梯形图程序，例如开门过程、关门过程、停止状态、楼层显示等等一系列的PLC梯形图同时也加以分析。最后总结了这次设计的结论和展望。是什么意思？

正在翻译，请等待...

This article first explains the choice of the purpose and significance of the lift, and an introduction to the origins, including elevators, structure, and development control, such as requirements analysis, and control the relay the elevator control system and PLC elevator control system. And then

First of all, this article explains the purpose and significance of the topic, introduction to elevators, including the origins, structure and development of the elevator, as well as their control and analysis of relay control features of elevator control system and PLC control elevator system. Then