
Switched-Reluctance Machines 7-21
With only ve terms in the polynomial representation, a very good t can be obtained. is is shown in
Figure 7.A.6 for the aligned inductance case, and in Figure 7.A.7 for the midway inductance case.
e analysis shows that using the polynomial approximation provides a very good approximation
for the Fourier series coecients in representing inductance and its current dependency [15,16]. Now it
is possible to write the Fourier expansion coecients in terms of the aligned, midway, and unaligned
2.5
2
1.5
1
0.5
0
0 10 20 30 40 50 60 70 80 90
Inductance versus current for midway position (θ = –15 °)
Current (A)