Research On Control Strategy And Driving System Of Six-phase Flux Switching Permanent Magnet Machines

Compared with traditional three-phase machine system,multiphase machine system has the advangtages of small torque ripple,high reliability,and satisfies the requirements of high power drive system.Therefore it is widely used in aviation,aerospace,ships,electric vehicles and other occasions with the requirements of high power and high reliability.Flux-Switching Permanent Magnet(FSPM)machine is a kind of novel brushless machine having magnets in the stator,offering not only high efficency and high power density,but also simple rotor structure,which is suitable for high-speed operation and easy for thermal dissipation,exhibiting a bright future by overcoming the shortages of the traditional brushless machines having magnets in the rotor.In this thesis,a six-phase FSPM machine which has two sets of three-phase windings phase shifted by 30 electrical degrees(dual three-phase FSPM)is chosen as research object.Its drive and control technique are deeply studied in this dissertation,the main research contents include:1.The structure and working principle of the dual three-phase 24/22 pole FSPM machine are introduced.The mathematical models based on the stator and rotor coordinate system are established respectively,and the simulation models are built.2.According to the actual machining experience,a set of machining technology suitable for FSPM machines is put forward,and a prototyped machine is manufactured.3.A detailed analysis of the control strategy of dual three-phase FSPM machine drive system is conducted,according to the complexity of the control effect and the implementation process,the most suitable modulation algorithm for this drive system is selected.4.An open-circuit fault tolerant strategy for the dual three-phase FSPM machine is proposed based on the principle of keeping the magneto-motive force constant under both healthy and faulty conditions.The thesis makes a detailed analysis of the one-phase and two-phase open circuit fault,especially compares the fault tolerant control performances with and without a neutral line,and verifies the effectiveness of proposed control algorithm by simulation.5.A DSP-based digital driving system is set up to verify the theoretical and simulated results.The principle and design process are introduced.6.According to the theory of control strategy and fault tolerance above,as well as the classic drive system principle,the software of C language program based on DSP chip is completed.7.The dual three-phase FSPM prototyped machine experiments are carried out on the digital driving system above to verify the theoretical and simulated results.