Analysis and Experimental Comparison of Acoustic Noise of Three Switched Reluctance Motors Made of Conventional Steel, High Silicon Steel, and Amorphous Iron
Haruki Sobue, Akira Chibá, Yifei Cai, Kyohei Kiyota, Yusuke Fujii, Kunihiro Senda, Soichiro Yoshizaki
Abstract
In this article, three test motors are fabricated with different iron materials, conventional steel, high silicon steel, and amorphous iron. Among the three materials, the high silicon steel has the lowest magnetostriction and the amorphous iron has the highest magnetostriction and the lowest saturated flux density. Hammer test is carried out to identify the respective resonant frequency and the optimum Young's modulus and Poisson ratio are identified from the measured resonant frequency for each core. Furthermore, the acoustic noise is measured in load test and it is found that the high silicon steel has the lowest acoustic noise. Then, the electromagnetic finite element analysis (FEA) and acoustic noise analysis are carried out. According to the FEA results, the acoustic noise of the amorphous iron motor is the lowest, while it is the highest in an experiment. This discrepancy is considered to be resulted from the magnetostriction property of the magnetic materials that are ignored in FEA so far. Therefore, the magnetostriction of three iron sheets is measured and the FEAs that take magnetostriction into consideration are carried out. From the results of the improved FEAs, it is found that the magnetostriction plays an important role in acoustic noise analysis.