Compare different starting methods for three-phase induction motors.

Direct-On-Line (DOL): simplest, full voltage applied, 5-8x current, used for small motors. Star-Delta: starts in star (1/3 voltage), switches to delta; reduces current to 1/3 but also starting torque. Autotransformer: reduced voltage start via taps, better torque/current ratio. Soft starter: thyristor-controlled voltage ramp-up, smooth acceleration. VFD: frequency ramp from low value, provides controlled starting with low current and full torque. Selection depends on motor size, load inertia, and supply limitations.