Optimization and comparison of C-core and E-core linear switched-flux PM machines with odd primary poles

Based on the optimal primary and secondary pole number combination selection rule of linear switched-flux PM machines (LSFPMM), the C-core and E-core LSFPMM with even primary poles has been proposed, which are optimized by individual parameter optimization. The results of individual parameter optimization with different secondary pole numbers are investigated and compared based on 2D finite element analysis (FEA). Furthermore, the effect of the assistant teeth on thrust force ripple has been analyzed. Based on the results, 9/17 primary/secondary pole numbers LSFPMM for C-core and E-core LSFPMM has the smallest thrust force ripple. Finally, the assistant teeth about LSFPMM are optimized by global optimization with scanning method. Compared the optimal C-core and E-core model, the results show the C-core 9/17 LSFPMM has the largest thrust force and back-EMF, but the E-core LSFPMM is suitable for fault-tolerant operation and has the lowest thrust force ripple.