Research On Simulation Of Fin Stabilizers Electrical Servo System Based On Direct Torque Control

Conventional servo system of fin stabilizers used to be electricity-liquid servo system. Because the electricity-liquid servo system has limitations such as high price, low precision and discommodious maintenance, lots of work has been done to investigate more efficient and cheaper servo system. With the prevalence of power-electronics technique and micro-control technique in recent years, electrical servo system, which has simple configuration, convenient control, high reliability and low price, has developed increasingly. So it is likely to become a new kind of fin stabilizers servo system. Replacing the conventional electricity-liquid servo system with electrical servo system, the cost is reduced greatly, the configuration is simplified and the maintenance is convenient. All the forenamed advantages facilitate the use of fin stabilizers on the medium and pint-size ships.Based on the technique of asynchronous motor direct torque control, this paper investigated the system structure and control law of fin stabilizers servo system, of which core was the asynchronous motor direct torque control technique, and improved on the quondam system according to the characteristic of fin stabilizers. With the software of MATLAB6.5/Simulink5.0, the fin stabilizers electrical servo system components were modeled, heights (2.68m,3.75m,4.26m) and angles (45° ,90° ,135°) of ocean wave were simulated. Moreover, problems in the simulations were discussed and solutions were offered. And at last, a conclusion was put forward to.A new kind of electrical servo system of fin stabilizers based on asynchronous motor direct torque control was proposed and simulated in this paper. The simulation results demonstrated that the fin stabilizers, which used the electrical servo system that based on asynchronous motor direct torque control, could follow the changed signal of fin stabilizers angle with speedy response and little dynamic error. Compared with the conventional servo system of fin stabilizers, electrical servo system had the advantages of smaller volume, lighter weight, lower price, more convenient control and higher reliability. So it could fulfill various operations of fin stabilizers.The electrical servo system of fin stabilizers that based on asynchronous motor direct torque control proposed in this paper is worth to be referenced in the field of the fin stabilizers servo system improvement.