Application guidelines for induction generators

There are numerous applications where induction generators offer distinct advantages over conventional synchronous machines, resulting in a simplified design and installation at lower first cost and substantial savings in operations and maintenance expenses. Induction generators, however, have some disadvantages which need to be evaluated before practical use. The major limitation being the need for an external source to supply the magnetizing current required to establish the magnetic field across the air gap. The purpose of this paper is to discuss the self-excitation requirements and other application problems that should be considered before installing induction generators. Special attention are given to the applications to low-head hydro, wind power and cogeneration plants in process industries and other dispersed generations.