An Adjustable Speed Synchronous Machine for Hydroelectric Power Applications

This paper describes results of study and model tests on the potential applicability of the doubly fed machine for relieving constraints inherent in hydropower applications. Although the literature contains many theoretical studies of the machine, this paper reports a more pragmatic examination of its characteristics and potential under a restricted set of conditions where its use may be most economically advantageous. The primary function of the machine in this type of application is to allow a modest range of speed adjustment, sufficient to maintain best turbine efficiency in spite of load and head variations. In so doing, cavitation and draft tube surging are also relieved.