Research On System Of Marine Direct-drive Double-fed Induction Shaft Generation

Doubly fed induction generator (DFIG) of AC rotor excitation is a new type of generator developed on the basis of the synchronous generator and induction generator.With development of the power electronics and computer control technology, the doubly-fed generator is used in an increasing number of power generation systems. As wind power technology matures, many scholars and technicians began to study the double-fed power generation technology which is used in other areas of the power generation.One of the most important areas is the ship power generation technology. With the mature of lower cost of power electronic devices and digital technologies, traditional DC shaft generator is likely to be replaced by AC doubly-fed generation. This article is in the context of the doubly-fed induction generator used in ship shaft generator system.First, this paper discusses the advantages of the double-fed asynchronous generator on the basis of the structure of the system, explain the shaft generator technology as a whole system, analysis and demonstrate the feasibility of this system with professional theory. Explain the two operational phase of the system of the generator, elaborated the rotor side inverter, grid side rectifier, oars and the operation of the entire system Harmonic may be encountered in the generation of energy pathways, instruct the situation of power generation,and given the solution method.Second, analysis the structure of the system’s hardware and software algorithms. Analysis the system hardware, discuss vector control of doubly-fed machine, and give the mathematical model. Rotor side inverter and grid side rectifier discussed in detail aim to explain the double-fed asynchronous power process of variable speed constant frequency. Then, under different control modes of the rectifier and inverter control strategy the PI parameter tuning method is given.Finally,analysis the data through a variety of debugging and simulation methods. Because of the complex structures and algorithms, use MATLAB simulink part of the system and the overall system to verify the feasibility of the system. Using this method and the theory design overall software and hardware, results prove doubly fed induction generator (DFIG) as the marine shaft generator is feasible and effective, it has engineering and practical significance for future research and system applications.