The Study Of Naval Vessel Electric Power System Stability

The stable operation of Naval vessel electric power system has special importance to Naval vessel. When Naval vessel fails, which sails in the ocean for a long time, it can not immediately get the support from the shore. But, when an important component runs wrong, it could lead to the destruction of Naval vessel and death of people, which makes Naval vessel depend on the supply of electricity very much. It not only requires Naval vessel electric power system to ensure the normal and stable operation of the electrical equipments in Naval vessel under normal circumstances, but also requires Naval vessel electric power system must has a certain stability under exceptional circumstances, to ensure and enhance the vitality of Naval vessel in highest measure. But, with the increasing of the size of Naval vessel electric power system, the traditional stability analysis methods based on experience can not meet with the requirements of stable operation of Naval vessel electric power system. So, to carry out the stability analysis and research to Naval vessel electric power system is very important.After consulting to a great deal of Chinese and English datum, this paper discusses the research background and the research significance firstly. Secondly, gives a detailed analysis of the building process of the nonlinear mathematical model of two generators in parallel of Naval vessel electric power system.Thirdly, based on the existing model, this paper draws on the mature theory of stability analysis of land-based power system and designs the first controller for the system, which is robust adaptive controller, to ensure system can operate stably when parameter uncertainty and external disturbance exist. In order to simplify the design of control rate, this article introduces backstepping to adaptive control to design robust adaptive controller. In this paper, Lyapunov stability criterion is used to judge the system stability.Finally, in this paper, we design another controller, which is fuzzy variable structure controller, to ensure system can operate stably when parameter perturbation exists. When fuzzy control and sliding mode control are combined,"chattering"phenomenon in sliding mode control system can be effectively weaken and we can combine the advantages of both.In order to verify the control effect of the controllers, in this paper, we write simulation program basing on Matlab6.5. We give out the simulation graphs such as the angle of rotors of system and the angular velocity of rotors of system. We can exert the electric power system transient stability criterion and judge the transient stability. Simulation results show that the controllers have good control performance, and the transient stability has been well controlled. When the external constant disturbance and the parameter uncertainty exist in system, robust adaptive controller can ensure system has good stability, and make two synchronous generators in parallel run back to synchronization quickly, so that system can return to stable operating state quickly. When parameter perturbation exists in system, fuzzy variable structure controller has strong robustness, which can make two synchronous generators in parallel run back to synchronization quickly, so that system can return to stable operating state quickly.