Abstract
Doubly-fed (adjustable-speed) pumped storage generating systems of large capacity have been installed in power systems with recent progress of power electronics technologies as its setting. Many papers have been published in which the enhancement of power system stability by application of doubly-fed machines has been described.
We propose in this paper new rotary equipment for power system operations. That is doubly-fed rotary frequency converter, which consists of 2 machines that are directly connected each other with shaft, and they are a set of doubly-fed machine and synchronous machine or a couple of doubly-fed machines.
Analytical models were newly developed in order to analyze and understand the behavior of the proposed doubly-fedrotary frequency converter. Basic control scheme for the doubly-fed rotary frequency converters is proposed. Results of studies on dynamic characteristics of the control systems applied in the converters are shown. Moreover, merits and demerits were discussed in comparison with static DC converter with thyristor valves from the practical point of view.
