毕设变频调速技术在中央空调系统中的应用.doc

PAGE PAGE I 摘 要 随着现代生活不断向智能化迈进，人们对中央空调的性能提出了更高的要求，如空调的舒适性、节能性等。本文介绍了在空调系统中使用智能化的冷水机组控制系统，通过在原来的老式中央空调系统上增设新的硬件设备以及编写软件程序，使电机的转速能够随着外界环境的变化实现自动的调节，从而既能提供舒适的生活环境，又能最大限度的节约能源。 本文在对中央空调的冷水机组循环系统组成结构进行分析后，指出了老式中央空调系统运行的种种不足之处，经过主电路控制方式论证，采用“一拖一”的方式对冷水机组循环系统进行变频控制。并给出主电路、控制电路的电气原理图。 文中还详细的介绍了中央空调温度控制系统的硬件和软件设计，包括三菱FX2N系列PLC、风泵专用变频器FR-F540-37K-CH工作原理，端子介绍，变频器参数预设值流程，PLC程序介绍等，最后形成了采用三菱FX2N-64MR PLC作为控制单元，通过交流变频调速器控制水泵速度，达到了系统根据实际负荷的情况调整流量，实现恒温控制，同时又可以节约大量能量的目的。 关键词：中央空调；PLC；变频器 PAGE II Abstract As modern become more intelligent day-by-day,people hope central air conditioner have more excellent capability,such as comfort and energy saving.This paper mostly research on how to use intelligent controller to control water circulation system of central air conditioner, make the motor speed can automatic adjustment with the external environment changing,we should add some new hardware devices and software programs so the air conditioner can supply comfort and use less energy as possible. In this paper,we analyze the composition of the water circulation system of central air conditioner,and pointed out that the old central air conditioning systemis running a variety of shortcomings,demonstrated the method through the main circuit,and using “one drag one way to control the system,continue give the main and the control circuit. In this paper,we introduce the hardware and software design for the control system. Including the SanLing FX2N Series PLC,pumps dedicated frequency conversion FR-F540-37K-CHs works,terminal description,parameter default process,PLC program description,etc.,And finally formed the SanLing FX2N-64MR PLC as the control unit,and drive pumps by frequency conversion achieve pumps speed adjustable.This control can adjust its power and carry out constant temperature,as well as save a great deal energy. Keywords: central air conditioner；PLC；frequency conversion PAGE IV 目 录 TOC \o 1-3 \h \z \u 摘 要 I Abstract II 第1章 前言 1 1.1 引言 1 1.2 空调控制方法的