Problems 1- Solution (a) A B C D nm 720 rpm (b) 0 1 0 0 0 45 1 1 0 0 90 0 1 0 0 135 0 1 1 0 720 12 rev / sec 60 Number of signals(ni bbles)/rev 8 nibbles/re v 180 0 0 1 0 Number of nibbles/re v 12 8 96 nibbles/se c 225 0 0 1 1 270 0 0 0 1 315 1 0 0 1 nm 1 2- Sketch a cross-sectional view of a single-stack variable reluctance stepper motor with 4 phases, 8 stator poles and 6 rotor poles. Determine its step angle. Solution (a) (b) m 4, N s 8, N r 6 360 45 8 360 r 60 6 s r 15 s or 8/6, four-phase SRM r m 60 15 4 2 3) Determine the step size and the step rate (no of steps/rev) for Five stake, four pole, 3 teeth/pole, variable reluctance stepper motor i-.. Solution S 5, N 4, x 3 360 360 6 S .N .x 5 4 3 360 No of steps / rev. 60 steps / rev 3