论述了替代进口控制系统的大庆天然气脱水装置控制系统的设计目标、设计思想、设计方案和实现技术，该设计采用了作者提出的实时系统的数据流／时间分析与设计方法，克服了原有系统的死机现象和切换跳闸现象．我们选择台湾研华计算机控制系统Ｃ选择Ｃ语言作为宿主编程语言，设计了多任务并发控制软件系统，实现了自动／半自动／手动方式的平稳切换。 The design objective, design idea, design scheme and realization technology of Daqing Natural Gas Dehydration Unit Control System which substitutes the import control system are discussed. The design adopts the data flow / time analysis and design method of the real-time system proposed by the author, The phenomenon of the crash and switch tripping phenomenon. We choose Taiwan Advantech Computer Control System C to choose C language as the host programming language, designed a multi-task concurrency control software system to achieve a smooth automatic / semi-automatic / manual switch.