抄録
Recently, high efficiency and low noise are required in the permanent magnet synchronous motors, such as DCBLM. The DCBLM generally has a conductive support ring, which prevents the permanent magnets from scattering by the centrifugal force, but eddy current loss in the support ring cannot be ignored for high efficiency. This paper's purpose is to analyze the eddy current loss in the support ring and the torque ripples by dynamic electro-magnetic analysis. For the purpose, the rotor rotation and the external inverter circuit which contains the diode circulating circuit at phase change interval are necessary to be taken into consideration in the field analysis.
In the paper, we give the dynamic electro-magnetic analysis method combined with the inverter circuit equations, and calculate the eddy current loss in the support ring and the torque ripples. In addition, the effect of the carrier frequency and the duty ratio to the loss is calculated.