Optimization Design Of Hybrid Excitation Permanent Magnet Synchronous Generator Utilizing Tooth Harmonic For Excitation

With harmonic excitation applied to hybrid excitation permanent magnet synchronous motor,a new hybrid excitation permanent magnet synchronous motor is formed,which not only maintains the high efficiency of permanent magnet synchronous motor and wide range of adjustment capability of electrically excited synchronous motor,but also realizes the brushless of the motor easily.The influencing factors of the rotor tooth harmonic electromotive force(EMF) of the hybrid excitation permanent magnet synchronous generator utilizing tooth harmonic for excitation are mainly analyzed in this paper.Then the influence of the motor design parameters on the rotor tooth harmonic EMF is analyzed to form an optimized design.The basic structure and working principle of the hybrid excitation synchronous generator utilizing stator harmonic for excitation and the hybrid excitation permanent magnet synchronous generator utilizing tooth harmonic for excitation are described.Five aspects of the causes and ways harmonic generated by the rotor harmonic EMF,the ability of the rotor harmonic winding inducing electromotive force, operating efficiency, the amount of copper winding and adjustment convenience of air gap magnetic field are analyzed and compared..The results show that excitation power of the motor utilizing tooth harmonic for excitation motor is provided by natural tooth harmonic magnetic field, which also has higher running efficiency, the less amount of copper winding.The influencing factors of the rotor core tooth harmonic winding voltage is analyzed qualitatively.Based on the finite element method, the influence of the air gap length,the stator slot width,the permanent magnet thickness,the rotor tooth harmonic wingding pitch and other motor design parameters on the rotor tooth harmonic winding voltage is calculated quantitatively.According to the calculated results, the fitting formula between the design parameters and rotor tooth harmonic winding voltage is deduced and its correctness is also verified,which provides good guide significance for optimization design of the new hybrid excitation permanent magnetsynchronous generator..According to the influence law of the motor design parameters on tooth harmonic winding voltage,an optimized design is obtained and the simulation of its operating characteristics is calculated.Then the voltage waveform and the characteristic curve of the armature winding and tooth harmonic winding are got,whose correctness is consistent with the theory.