Abstract
Refurbishment of hydro-generators promises an increased lifespan and
improved efficiency. Old generators are not only less efficient but also
less reliable; their fault occurrence is more common. The economic
impact of out-service time can be astronomical. Thus, refurbishment is a
critical task; but it is challenging too. Most of the conducted works
focus on the material update, enhancing the cooling network, and
obtaining better efficiencies. Modifying winding type, i.e. conversion
from lap winding to wave winding is rare since it often requires a
change in the slot number. Such a move can be laborious, size change can
become mandatory. In this study, a refurbishment design strategy is
proposed which includes a winding type conversion. The task is to
implement a wave winding since it has less out-service time and is
easily replaced by field workers. In this paper, an old generator that
started operation in 1956 is used for a refurbishment. This study
promises a guideline to hydro-generator designers who work on a
refurbishment study on old hydro-generators that have diamond coils.