The Design And Research On Ship Main Engine Control System

With the development of the network and intelligence in shipping industry, the integration level of shipping is higher and higher. This thesis mainly focuses on a system which is one branch of a whole network integration control system—ship main engine control system. The system targets for the main engine SNO.1220 made by KANASASHI in Japan with the distributed structure, in order that the monitoring, controlling and the managing can be done at the same time, It successfully achieves all the functions of the ship main engine control system and applies the arithmetic of parameter auto-tuning PID based on fuzzy rules in speed regulation system of the main engine. As a result, it greatly improves the high quality speed regulation of the main engine and the safety and speediness of ship.In the monitor and management part of the whole system, it mainly achieves the function of displaying the important data during the running process of the main-engine, the real-time curve, the historic curve, the state of the main-engine, the real-time warning and the function of setting the control parameter and setting of the warning restriction value and so on. In the control part, it adopts the controller S7-300 PLC, which achieves the functions of the startup, the reversing, the repeated startup, speed regulation and critical speed avoidance of the main engine. Meanwhile, some important messages and data could arrive at the offices of the captain and the chief engineer through LAN. This can let them learn the running state of the main-engine timely and clearly. In this way, they can make right decisions and make sure the safety of the ship.The speed regulation of the main-engine is always the keystone and difficulty of the main-engine control system. Since the speed regulation of the main-engine is a complex system with the characters of the non-linear, time-variation and big-lag, yet nowadays, most ship still adopt the traditional PID controller; it cannot adapt the high quality speed regulation of the main engine. From this point, this thesis focuses on a kind of parameter auto- tuning PID controller based on fuzzy rules, which can regulate the PID parameter according to the rotate speed's errors and its rate of change.In the condition of the lab, the controller is compared with the traditional one via simulating. It has the advantages of less overshoot, less transition time, less frequency of oscillation, stronger stability and robustness; we can make the conclusion that it can satisfy the requirements of the main-engine and has a wide applying prospect and practical value in the long run.