Study Of The Monitoring System Of Ship Electric Propelling

The electric power propelling is one of the ship propelling methods. After hundred of years development, the advanced power electronics technique and the technique of variable frequency modulation velocity of the large power alternating current motor are becoming more and more mature today. And the ship power propeller is used so widely that it is becoming the main development direction of the ship propeller. With the rapid development of digital communication of computer, the remote control technique and the expending of their application field, it is an inevitable trend to use computer to control the ship electric propelling system.According to the requirement of the remote control of main engine and the teaching experiment, a real-time monitoring system of ship power propulsion with two engines and two propellers is designed. This system applies both industrial controlled computer and MCU as two control parts, and adopting the RS485 bus communication through the serial port. Under the control of monitoring software, the industrial controlled computer can accomplish the control of the start, stop, and the speed of the ship propeller motor, the advancing, reversing and parking of the propeller. It can realize the real-time monitoring of the working state of ship propelling motor, frequency converter, gear box and the propeller so that the remote monitoring of marine engine operating system can be achieved.This paper generally introduced the constitution, principle and the main function of the electric power propeller monitoring system of the ship with two engines and two propellers. The design process of the communication program of industrial controlled computer, propeller monitoring program and the human-computer interface program is described in detail, including the communication protocol and related setting, using MSComm to control the serial port,the employ of digital I/O control card PCL - 733/734 and so on. Finally, the debug results and the source program of each function list are given. In addition, this paper expounded the theory of variable frequency modulation velocity of alternating current three-phase asynchronous motor, establishes the mathematical model, presented the control project and analyzed the characteristic of propulsion system. And this is the theory base of the following design on the subject.The debugging result demonstrated a friendly interface, convenient operation and good effect of the supervising and control system.