【作者】 瞿旻；

【导师】 张颖超；

【作者基本信息】 南京信息工程大学 ， 系统分析与集成， 2008， 硕士

【摘要】 油库是石化供应链中重要的一个环节,油库系统的安全至关重要。在油库日常的生产操作环节中不可避免的存在易燃易爆气体,若任由这些气体在环境中积聚或泄漏,易造成爆炸、燃烧等恶性事故,因此必须及时排除。目前,我国可燃性气体报警系统一方面以单片机开发报警器居多,其精度、稳定性和扩展性不佳,难以适应信息化发展的要求:另一方面,报警器多数以发出声光报警的方式提示操作人员进行排风操作,自动化程度较低。随着自动化与信息化技术在石化行业的广泛推广和应用,对可燃性气体报警系统提出了更高的要求。本文基于某公司石化行业的可燃性气体报警系统项目,旨在提高报警系统的信息化和自动化水平,以满足用户的需求。根据控制系统发展状况与当前可燃性报警系统发展趋势,我们提出了相应开发方案,并结合公司实际情况与要求,选择了以下位机硬件采集控制和上位机软件监控的架构。在下位机系统中,通过PLC(可编程逻辑控制器)来采集现场模拟量信号,处理现场数字量信号。在RS485串行通信标准基础上采用MODBUS通信协议实现PLC与气体探测器通信读取数据,通过通讯卡实现PLC与PC机的PROFIBUS通信,并通过对继电器的控制来控制风机开关,以实现自动控制。在上位机器监视系统中,我们采用Ifix组态软件开发人机界面,生产实时状况,不仅直观形象,也方便操作人员进行监控和记录查询等操作。实践证明,本可燃性气体报警系统数据采集高效、准确,运行稳定,降低了劳动强度,提高了工作效率,体现了信息化促进工业化的特点,达到了预期设计效果。更多还原

【Abstract】 Oil Depot is an important step in the petrochemical industry supply chain, so the security of the Oil Depot System is very important. The inflammable gas and explosive gas exist unavoidably in the daily production link and operation link of Oil Depot. The gas’ accumulation and leaking in the environment will easily cause malignant accidents such as explosion, combustion,etc. So the must be eliminated in time. At present, the flammable gas alarming systems in China are developed by MCU beefs, so their accuracy, stability, and expansibility are not very good, which is difficult to meet the requirement of the development of the informatization. Also, most of the annunciators only alarm by sending out sound and light to suggest the operator to take the operation of discharging the gas, the automatic degree of which is relatively low. With the widely popularization and application of automation and informatization on fossilization industry, higher requirements are proposed to flammable gas alarming systems.This paper based on a certain company’s project of flammable gas alarming system on fossilization industry, it aims to improve the information and automation level of the alarming system in case to meet the user’s requirements. According to the development status of Control System and the current development trend of Flammable Gas Alarming Systems, we proposed relevant exploitation plan. Combined with the company’s practical situation and requirements, we choose the structure that inferior hardware system collect and control, superior software system monitor. In the inferior hardware system, PLC collects the field analog signal and processes the field digital signal. On the RS485 serial communication standard, we realize the communication between PLC and gas detector by using MODBUS protocol, realize the PROFIBUS communication between PLC and PC by communication card, realize the automatic control to fans by controlling the relay. In the superior software system, we use IFIX configuration software to develop the system to support the guests to find out the real-time running situation of the field in time, which not only be visual but also be convenient for the operators’ operation such as monitoring, recording, querying and etc.Actual uses show that Flammable Gas Alarming Systems can collect data efficiently and accurately, and runs steadily. It decreases the working intention, improves the efficiency of work, and reflects the feature that information promotes industrialization. The perspective purpose is carried out.更多还原