Determine the main dimensions, turns per phase, number of slots, cond…

Question

Determine the main dimensions, turns per phase, number of slots, conductor cross section and slot area of a 250 h.p., 3 phase, 50 Hz., 400V, 1410 r.p.m. slip ring induction motor. Assume $B_{av} = 0.5 \text{ Wb/m}^2$, $ac = 30000 \text{ A/m}$, efficiency = 0.9, power factor = 0.9, winding factor = 0.955, current density = $3.5 \text{ A/m}^2$. The slot space factor is 0.4 and the ratio of core length to pole pitch is 1.2. The machine is delta connected.