2015 Volume 23 Issue 1 Pages 193-198
Past magnetic property measuring methods such as the single sheet test (SST) and the Epstein method cannot quantitatively evaluate magnetic properties of an actual stator core that shows complex shape. Therefore, we are researching the stator winding excitation method as a new method to evaluate magnetic properties (iron loss and maximum magnetic flux density at a tooth) of an actual stator core after each manufacturing process. This method can directly measure them using a dummy rotor and a three-phase stator winding. To actualize this method, we constructed a new measuring system that consists of an iron loss measurement system and a multichannel data acquisition system. According to our experimental result using the proposed iron loss measurement system, the iron loss of the actual stator core that completed all manufacturing processes was about 2.3 times larger than an iron loss of an unprocessed electrical steel sheet. In addition, the proposed multichannel data acquisition system shows observation results of the magnetic flux density waveform and of maximum magnetic flux density at each tooth of the shrink fitting processed actual stator core. From our observation result, maximum magnetic flux density at each tooth was influenced by the compressive stress of a frame.
