Dynamic analysis of a grid-connected induction generator driven by a wave-energy turbine through hunting networks

The presence of forced oscillations occurring in a Wells turbine driven grid-connected induction generator enables one to seek a solution by considering the analogy between the dynamics of Wells turbine driven systems with those associated with diesel-engine driven generators or electric motors driving reciprocating compressors, where also such forced oscillations occur, although there they occur in synchronism with shaft-position or speed. This difference is taken into account and the hunting network theory, which has hitherto been applied to the dynamic analysis of motors driving reciprocating compressors, is here applied to analyse the dynamics of a Wells turbine driven grid-connected induction generator. The method enables the generator current, power and slip to be predicted from a knowledge of the shaft-torque harmonics. The result is compared with that obtained through d-q analysis.