Evolution de la technologie des turbines " bulbe " appliquée aux petites centrales

Bulb technology for Mini Hydro schemes

VA Tech Bouvier Hydra 49, dd Paul Langevin, BP 7, 38601 Fontaine Cedex, France

Auteur de correspondance : jacques.fonkenell@bouvierhydra.fr

Abstract

The small bulb technology was born in the early thirties, based on the swiss company Escher Wyss patents, and applied during the following years on numerous low head sites, mainly in the south of Bavaria. The technology progresses faced some difficulties due to the generator cooling system. In the early fifties, the French engineers try to solve these problems and imagine a new oil cooling system. With this new approach, tens of small output sites were equipped. In the meantime, the big bulbs were developed. especially for tidal and large discharge applications. But in the recent years, the high costs of direct coupled low speed generator have led the manufacturers to install speed increasers. The present renewal of interest for small hydro should constitute a new impulse for this kind of units, if acceptable solutions can be found to remove the speed increaser on an economical basis. Considering the environmental criteria growing importance, the small bulb turbine would become an ideal tool for low head applications.