Fitting Method of Experimentally Measured 3D Loss and Torque Maps to design Optimal Trajectories for IPMSM

Interior Permanent Magnet Synchronous Motors (IPMSMs) used in the electrical machineries and apparatuses are often driven under given drive conditions such as operation time, rotating speed, and rotational angle. In order to reduce the energy loss of the motor during their variable speed operation under given drive conditions, various design methods of the optimal traj ectories have been reported. A numerical design method using theoretically composed 3-dimensional loss map has been reported, however, the map should be measured by experiments and it may have data variations and measurement errors due to experiments. These variations and errors affect the resulting trajectories. This paper adopts the fitting method for experimentally measured data based on the least squares method in order to obtain 3-dimentional loss and torque maps. Then the optimal trajectories without fluctuation will be derived.