目 录 1 绪论 ······································································································································· V 1.1 高炉上料 PLC 自动控制的研究目的、 意义 ······························································· V 1.2 PLC 在自动控制中的现状 ··························································································· V 1.3 PLC 控制系统的优点 ································································································· VI 1.4 PLC 的发展以及对高炉上料的进一步革新 ······························································ VII 2 控制系统总体方案设计 ········································································································ IX 2.1 炼铁工艺过程介绍 ···································································································· IX 2.2 高炉内炉料还原反应原理简介 ··················································································· X 2.3 控制方式的确定 ········································································································· XI 2.4 操作方式 ···················································································································· XI 2.5 设计概述 ··················································································································· XII 2.5.1 传统控制方式 ········································································································ XII 2. 5. 1 PLC 的控制方式 ··································································································· XII 3 控制系统的硬件设计 ········································································································· XIV 3.1 微型计算机的选择 ··································································································· XIV 3.2 PLC 的简介 ··············································································································· XV 3. 21PLC 的基本结构 ······································································································· XV 3. 2. 2PLC 的工作原理 ···································································································· XVI 3.3 PLC 的选型 ············································································································ XVII 3. 3. 1 选型规则 ············································································································ XVII 3. 3. 2 系统选型注意事项 ······························································································· XX 3.4 步进电机的选择 ······································································································· XXI 3. 4. 1 步进电机简介 ······································································································ XXI 3. 4. 2 步进电机选型规则 ···························································································· XXII 3. 4. 3 步进电机应用中的注意事项 ············································································· XXII 3. 4. 4PLC 实现与步进电机的通信 ·············································································· XXIII 3.5 料位传感器—高炉探尺 ························································································· XXIV 3. 5. 1 高炉探尺简介 ··································································································· XXIV 3. 5. 2 高炉探尺工作原理 ···························································································· XXV 3.6 其他硬件配置 ········································································································· XXV 4 STEP 7 与软件编制 ······································································································ XXVIII 4.1 PLC 程序设计步骤 ····························································································· XXVIII 4.2 编程环境 ················································································································ XXX 4.3 编程语言 ······················································································ 错误！ 未定义书签。 4.4CPU 选型 ················································································································ XXXI 4.5 扩展模块选型 ··············································································· 错误！ 未定义书签。 4.6I/O 口分配 ··········································································································· XXXIV 4.7 顺序功能图 ·········································································································· XXXV 4.8 系统梯形图 ········································································································ XXXVII
