A Study on Utilization of Variable Speed Micro-Hydropower System

A conventional hydropower system for variable head is not suitable for micro-hydropower because of relatively high cost.In this study,two variable speed micro-hydro power systems that consist of low-cost commercial power electronic elements are developed for variable head micro-hydropower.One is composed of a synchronous generator and an electronic load governor for the purpose of applying to an isolated operation,and the other is composed of an induction generator for the purpose of connecting to power system.The experimental results showed that turbine performance and total system efficiency at off-design heads are improved much by using these systems.The performance characteristics of a simplified low-head cross-flow turbine are also determined experimentally in the wide range of head