Fuzzy logic based soft-start for induction motor drives

In recent years, fuzzy logic has received greater emphasis in the field of power electronics and motion control by virtue of its adaptive capability. A novel fuzzy logic based soft-start scheme for induction motor drives close to optimal performance has been discussed here using microprocessor based thyristorised voltage controller. Rule-based soft-start algorithm is fully realised through a software approach only. The soft-start strategy is based on the rise in the power drawn during starting period and the sudden fall in its magnitude at the end of soft-start has been used conceptually in closed-loop. The prototype has been tested under various loading conditions and found to be reliable and near optimal.