CONCLUSION
This paper has presented an innovative permanent-magnet motor with
movable stators. The flux density distribution and flux lines vary
with movable stator positions, thereby varying the motor torque
based on movable stator positions. The analytical model of movable
stators has been established and validated by using the ANSYS
Maxwell software. 2-D numerical results are generated and compared
with analytical results. The torque of permanent-magnet motors can
be varied by moving the movable stators, according to both
numerical and analytical results. Concerning motor torque variation
capability achieved in this study, according to Figure 15, the
ratio of the largest vs. the smallest torque is calculated as 53/23
= 2.3. In comparison, the 1st, 2nd, and 3rd gear ratios of
traditional transmission in gasoline sedans such as VW Golf are
3.9, 3.45, and 1.9, respectively. Although the traditional
transmission in gasoline sedans still has advantages in torque
ratios, the weight and volume of transmissions increase fuel
consumption of gasoline sedans. By contrast, the permanent magnet
motor with movable stators proposed in this study is effective and
promising in direct drive systems.
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