The Design Of An Automatic Control System For Dynamic Curved Plane Skimmers

With the rapid development of China's economy, it demands an increasing amount of petroleum and then the transportation of petroleum is booming as well. The soar of vessel number and transportation volume of oil, especially for the large and super large scale oil tankers, makes the offshore traffic environment much more complicated, which furthermore causes a high risk of marine oil spills. Once the spills occur, an in-time and efficient measurer must be taken in order to clean the spilt oil. Otherwise, it would do a catastrophic harm to the marine environment and ecological resources. Nowadays, the prime way to recover the split oil in the sea is using skimmers. However, most of the existing skimmers need improving because of disadvantages such as low capacity and efficiency in recovering, complexity in structure and high dependence on running conditions. Few researches have been done in the area of automatic system for recovering spilt oil in China.Dealing with such a condition, this thesis takes a research on a new type of dynamic curved plane skimmer that has a function of pre-separating for oil and water, and then designs an automatic control system. The specific work is as followed:Firstly, based on the fuzzy control theory, obtained the input and output membership function and valuation table, then according to the drafted control scenario, established a fuzzy control table and followed by a fuzzy self-tuning PID controller for the dynamic curved plane skimmer; secondly, applying the valve-controlled hydraulic system theory, designed the hydraulic part in the automatic control system for the dynamic curved plane skimmer, and offered a calculation method for type selection for certain system elements; thirdly, with the use of AVR MCU as the controller, designed input signals processing circuit, output signals processing circuit, digital display circuit and so on, which compose the hardware circuit in the automatic control system for the dynamic curved plane skimmer, and then programmed in AVR MCU; finally, simulated the fuzzy self-tuning PID controller and the entire automatic control system in MATLAB. The test results indicate that the fuzzy self-tuning PID controller improves the control performance in the system and fulfills the related control requirements in a good way.