Dynamics of a vertical axis hydrokinetic energy conversion system with a rectifier coupled multi-pole permanent magnet generator

Abstract

Hydrokinetic energy conversion systems (HECSs) are increasingly being considered as attractive alternative solutions for electric power generation from marine/tidal currents, river streams and other artificial waterways. Use of vertical axis turbines and multi-pole permanent magnet generators (PMGs) are also gaining considerable attention. This work develops a set of dynamic numerical models for vertical axis turbines that employ PMGs for electromechanical energy conversion. Issues such as weak startup behaviour, torque-ripple propagation and system losses are accommodated in the formulations. With emphasis on the electrical and electromechanical subsystems, various key observations have been validated through experiments conducted in a controlled environment. The modelling scheme has been found to be flexible and detailed enough in representing the expected system behaviour. Various limitations and scope of further work are also highlighted in this work.