HWSS-2000型生活热水供应系统-PLC控制方案设计(论文17000字)
Research on HWSS-2000-type Hot Water Supply System — Scheme Design of Programmable Logic Controller System
摘 要
本文设计的HWSS-2000型生活热水供应系统是为大学生宿舍提供生活热水的。该宿舍楼有12层共住学生约2000人，设计成为三个独立的热水供给单元：高区、中区和低区。
本文采用太阳能集热器与空气源热水机组相结合的热源配置方式：以空气源热源为主，太阳能热源为辅；既考虑提高能效比，又考虑满足恶劣气候条件下的热水供给需要。
本文进行了水力计算与校核、热量与电功率负荷计算；基于计算参数进行了管路配置与机电设备的选型。本文设计了电气控制系统和PLC控制方案，并设计了PLC控制程序，实现了水位控制、水温控制、太阳能热水循环控制、分时段加热与供水等控制功能。
本文采用了恒压变频供水方式以节能为目的，设计了高区、中区、低区三个独立的热水供给单元：每个单元由1个变频器和3个水泵—电机组组成，由1个PLC进行控制，实现二用一备的控制功能和进行工频/变频工作模式的切换，并能根据用水需求量的大小与供水压力的高低，自动变频实现恒压供水控制功能。
关键词：热水供应系统；太阳能集热器；空气源热泵；恒压变频供水；PLC控制
Abstract
HWSS-2000-type hot water supply system designed in this thesis is to provide daily used hot water for college students living in a dormitory building, which has 12 floors with about 2,000 students. This supply system consists of three units, i.e. higher floor unit, medium floor unit and lower floor unit.
In this thesis , air source hot water units have been adopted and combined with solar heat collectors as heat source configuration. The control principle is using the air source heat as main heat source while using solar heat as supplementary heat source, in order to improve the energy efficiency ratio in consideration of sufficient hot water supply under bad weather conditions.
In this thesis, we have calculated the pressure loss in pipeline, heat load and electric power needed. Based on the calculation results, the piping configuration and selection of mechanical and electrical equipment have been carried out. In this thesis, we have designed the electrical control system, PLC control scheme, and PLC control program, in order to realize the control of water level and water temperature in tank, the control of solar heat collectors and hot water circulation, the time-interval control of hot water supply and hot water heating systems.
In this thesis, a frequency conversion and constant-pressure water-supply system has been used for the purpose of energy saving, which consists of three units, i.e. higher floor unit, medium floor unit and lower floor unit. Each unit consists of a frequency converter and three water pump - motor devices controlled by a PLC, in order to realize the function of 2 pumps in operation and one pump in standby, the function of work mode switch, and the function of automatic regulation of water supply pressure according to the practical demand for water flow rate and supply pressure.
Keywords: hot water supply system; solar heat collector; air source heat pump; frequency conversion and constant-pressure water-supply system; programmable logic controller
目 录
摘要 Ⅲ
Abstract IV
目录 V
第1章 绪论 1
1.1课题背景 1
1.2 任务书 3
1.3 工程概述 3
1.4设计方案论述 3
第2章 水系统设计 7
2.1 水箱与机组的计算 7
2.2 管系分布设计与管径选取 10
2.3 管系压力损失计算 12
2.4 循环泵﹑离心泵的选型 12
2.5 管系压力和流量校核 14
第3章 系统模块原理 18
3.1 空气源热泵模块 18
3.2 恒压变频模块 20
3.3 太阳能模块 22
第4章 电气控制系统设计 23
4.1 LOGO的介绍 23
4.2 电气控制系统的功能设计 24
4.3 空气源集控箱系统的设计 32
第5章 PLC程序设计 35
5.1 恒压变频程序设计 35
5.2 集控箱程序设计 41
参考文献 47
总结 49
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