Revision of the criteria for generators specifications and project: the electric parameters and stability-case analysis

The authors aim that this article can be an agent of collective reflection for both the hydrogenerator's project engineers and the users. It is an invitation to discussions about some, so called, old dogmas, concerning the specification of short circuit ratio (SCR) and subtransient ratio (X"q/X"d), that might deserve a revision under the light of a new technology, now available for the voltage and speed regulators. Transient simulations were performed by the authors in machines projected under the classical way and under new criteria, to allow for comparisons. The results lead to a possible revision of the presently applied practices for those parameters.