混合型高温超导发电机采用高温超导带材作励磁材料,结构上与传统电机有较大的不同,设计方法也不尽相同.本文基于傅里叶变换将超导发电机的励磁集中绕组等效为沿转子圆周正弦分布的激励源,建立了超导发电机磁场分析模型.对电机气隙磁场分布进行了求解,并分析了不同绕组张角时气隙磁密波形中的谐波含量.通过参数化分析,研究了不同环境屏、转子的尺寸对电机功率密度的影响.采用有限元法对磁场求解结果进行了验证,结果一致性较好.研究结果表明,励磁绕组张角会对电机气隙磁密波形产生影响,合理设置超导发电机环境屏及转子结构,可以提高超导发动机的功率密度.
Adopting high temperature superconducting tapes, Hybrid superconducting generators had, compared to traditional ones, different structures, and so did the design method. In this paper, using Fourier Decomposition, the concentrated winding of the generator could be equivalent to sinusoidal distributed ones along the rotor surface. Based on the results, analytical method was used to calculate the magnetic field. Harmonics contained in the waveform of air-gap magnetic flux density were evaluated at different winding open angles. By conducting parametric analysis, changes of the generator's power density according to the sizes of environmental shield and rotor were also studied in this paper. Results of the magnetic field calculation gained by Analytical Method had a good agreement with those by Finite Element Method. Researches revealed that, the open angle of the field winding had an effect on the waveform and amplitude of air-gap magnetic flux density, and proper thicknesses of the environmental shield and rotor could enhance the power density of the generator.