Tanker Electrostatic Explosion-proof Intelligent Control System

Static electricity is a very dangerous potential factor to the safety of oil tankers. And many potential factors may give rise to electrostatic ignition or electrostatic explosion in the process of loading, unloading or shipping oil cargoes or during the course of washing tanks. So far all kinds of operations on oil tankers are carried out in accordance with specific safety regulations, technical rules or strict operation rules both at home and abroad because such accidents are complicated, accidental and unrepresentable.This dissertation, from the viewpoint of control, is aimed to set up a fuzzy-logic-based supervising system to prevent electrostatic explosion of oil tankers. This system makes use of the advantages of fuzzy logic, and needs not to set up an accurate mathematics model. According to specialists?experience, such dangerous factors as water temperature, water pressure, oxygen density in the tank, the temperature and pressure of water vapor, ect. As well as control rules are made out in safety regulations for oil tankers. By using fuzzy logic (MIN-MAX reasoning), all sorts of fuzzy information are processed so as to simplify the control procedure in addition to realize it.At the same time, neural networks (back-propagation algori-thm) is applied to calculate the dangerous factors (the voltage and the electric field intensity in tanks) which can not be measured on the spot, and to aid fuzzy FDcontrol. Thus the dangerous factors can be supervised and controlled, and electrostatic explosion is prevented. Based on field-bus control system (FCS), an intelligent monitor system is designed in which intelligent modes are used to complete data collection, simultaneous supervision and communication. This method simplifies the structure of the monitor and control system, enhances its reliability and has realized whole-process control, therefore greatly decreases the possibility of accident.Furthermore, simulations computer test based on test data has been carried out in the two procedures of cargo loading and unloading and has shown very encouraging results.