The Design Of Safety Control System For Ship Oil To Gas And Its Software Implementation

As the serious crisis of oil resource and the rapid development of the global shipping industry, huge oil consumption and environmental pollution caused by shipping have aroused much more concern of the society. LNG(Liquefied Natural Gas) is a clean energy, whose development and utilization can effectively reduce the pressure on oil supply and the environment pollution. Therefore, using LNG as the fuel of the ships has been researched and developed widely. In current China, to make full use of the ships which have already been built and operated, the LNG powered ships are mainly transformed from the pure oil power ships, and the process is called "oil to gas". According to needs of the automatic control and the fire safety system of the "oil to gas" ships, this thesis uses the PLC(Programmable Logic Controller) and the touch screen as the core controller and HMI(Human Machine Interface), and develops the PLC application program as well as the HMI configuration of the fire safety and automatic control systems of the diesel oil-LNG dual-fuel powered ships finally. Currently, the box equipped with the designed safety control system has already been used in engineering. The main work and contributions of this thesis are as follows.(1) The overall framework of the automatic control and fire safety/alarm system has been worked out. The function and control mode of the safety control system has been set according to the analysis of the automatic control demand on the diesel oil-LNG dual-fuel powered ships. After analyzing the importance of the fire safety and the emphasis of “oil to gas” ships transformation, the fire alarm system has been designed and improved.(2) After merging the automatic control system and the fire safety system of the diesel oil-LNG dual-fuel powered ships, the logic diagrams and blocking of the system, the input and output ports assignment and the PLC programs are all completed. Then, the debugging and simulation of the designed PLC programs are done as well.(3) By using touch screen and its configuration software, the HMI of the safety control system is designed, which is also simulated in simulating environment to identify and revise the function shortages of the designed HMI configuration project.