Analysis Of Hybrid Excitation Synchronous Generator With Rectifier Load Based On Tooth Harmonic

In the fields of aerospace,ship power system and renewable energy development,synchronous generator with rectifier load system as the power generation device of DC transmission system has great advantages.The hybrid excitation generator with tooth harmonic excitation combines the harmonic excitation technology with the hybrid excitation technology to form a new type of hybrid excitation generator with self-excitation and no brush,which has a broad application prospect.The research and analysis of the motor with rectifier load is of great significance to broaden the field of high-quality DC power supply.The development history of hybrid excitation synchronous generator,harmonic excitation synchronous generator and synchronous generator with rectifier load system,as well as the research status at home and abroad are briefly described.Based on the basic theory of tooth harmonic,the factors that affect the output field current of tooth harmonic excitation system are derived and analyzed.The influence of design parameters such as stator slot width,air gap length,stator slot,number of turns of tooth harmonic winding and magnetic circuit saturation on the field current is quantitatively calculated by using the finite element method.The simulation results verify the correctness of the theoretical analysis and get the optimal value of each parameter under the maximum output excitation power.The optimal arrangement of the tooth harmonic winding is applied to the rectifier load of the hybrid excitation generator with tooth harmonic excitation(power factor is 0.9).The output characteristics of the generator with rectifier load before and after the tooth harmonic winding optimization are compared and analyzed by the field circuit coupling time-step finite element method.The results show that the optimal arrangement of tooth harmonic winding can make the generator output constant voltage with different rectifier loads.At the same time,the Fourier analysis of the harmonic components of the line voltage of the generator with rectifier load in the case of the tooth harmonic excitation system off and on is carried out,and the reason of the waveform distortion of the line voltage is obtained.In view of the influence of the increase of the harmonic content on the stator core loss of the hybrid excitation generator with the rectifier load,the influence of the line voltage harmonic component on the stator core loss is calculated by the traditional stator core loss model,and the stator core loss in three cases is calculated by the finite element method.The comparison between simulation results and calculation results shows that the accuracy of this method is high.The generator prototype test platform is established,and the performance of the tooth harmonic excitation system is tested.Five different connection modes of two sets of tooth harmonic winding are designed.The no-load test and load test of the prototype are carried out respectively,and the best connection mode of the two sets of tooth harmonic winding is obtained when the maximum excitation power is output.The prototype experiment of the generator with rectifier load before the optimization of the tooth harmonic winding is carried out,and the experimental results are consistent with the simulation results.