Analysis And Simulation Of Disk Brushless Doubly-fed Machine

Disk brushless doubly-fed machine (DBDFM) is a novel AC machine. It has advantages of conventional cascade brushless doubly-fed machine as good coupling ability and high efficiency, as the same time, and it also has single stator structure brushless doubly-fed machine advantages as little volume and less material cost. The capacity of frequency converter can be reduced by using DBDFM in adjusting-speed system, so the system cost is low. DBDFM works more reliably for its brushless structure and the character that it can maintain working when the frequency converter is broken down. There is detailed research on this novel machine in this paper, and it mainly includes the followings.Firstly, based on the electrical machine theory, the operation theory of DBDFM is deduced in this paper. Slips of DBDFM are defined, and the formulas of relationship between slips are built. The equivalent electrical circuit is derived according to the built voltage formulas of DBDFM. The energy flowing relationships of every operational state are also studied in this paper. Therefore, all those above make up the whole basic theory system of DBDFM.Secondly, electromagnetic design theory of DBDFM is researched in this paper. The novel structure of this machine and specialty of magnetic circuit are illustrated, also the electromagnetic design method is found, further more, computer aid electromagnetic design program is finished. A model machine is designed, and its parameters are calculated by using the program.Thirdly, the mathematic models of every operation state are built, and also the simulation programs by using MATLAB language are finished in this paper. Through the simulation results, conclusions can be got that when DBDFM works in sum modulation mode, good characters can be gained, so there are broad applied prospects; but in the difference modulation mode, the efficiency is low, so it can not fit for adjusting-speed system. By researching on appropriate pole numbers combination, another conclusion can be got that the pole number of power unit should be larger than control unit, thus, better performance will be gained.Finally, the parameters calculation and performance simulation software is finished, and it can not only perform that electromagnetic design of any pole numbers combination DBDFM, also can simulate any operation state. All dimension parameters are inputted from interfaces, and the results of calculated parameter and the simulations are outputted in the interfaces. The software has many advantages as friendly interface, easy operation and rapid calculation speed. Therefore, it could provide the convenience for the further study and popularization application.