基于有限元法的多相同步发电机空载特性分析及额定励磁电流计算

针对多相同步发电机铁心的磁非线性和结构复杂性,采用非线性有限元法,建立了电机计算模型,对空载特性与额定励磁电流的计算进行了研究。以一台十二相同步发电机为例,在电磁场计算的基础上,对气隙磁场进行了谐波分析及空载特性计算,计算所得基波电势与实测结果吻合,表明此法可用于电机电磁场计算,能给电机设计提供理论依据。在此基础上通过内功率因数角等参数的迭代,计算得到了与额定工况相符的励磁电流,其方法有较高的实用性,可为一般同步发电机励磁电流计算提供参考。

No-load Characteristics Analysis and Rated Field Current Calculation of Multi-phase Synchronous Generator Based on FEM

Considering the magnetic nonlinear characteristic of iron core and its structural complexity,the calculation model of Multi-phase Synchronous Generator is established with nonlinear FEM.Then the method and analysis steps of no-load characteristics analysis and rated field current calculation are given in detail.On the basis of electromagnetic field calculation of the twelve-phase synchronous generator,the harmonic analysis of air-gap magnetic field is presented,as well as its no-load characteristics.The calculated results of fundamental component are close to the measurement values,and it indicates that this method can be used in the calculation of electromagnetic field of the generator.Also,it gives the theoretical basis for the generator design.The rated field current is calculated based on iterative method,and the results of field current are consistent with the rated condition.This method has high practical usability,which may provide the reference for the calculation of rated field current of the common synchronous generator.