Certain Design Aspects of Single-Winding Three-Phase Inductor Alternators

Based on mathematical analysis, this paper points out that restrictions in stator/rotor slot combinations for optimum output of a conventional inductor alternator are not applicable for one with a single winding for both dc excitation and output. Design considerations for the latter are discussed, and it is demonstrated that its performance is superior to a conventional double-winding inductor alternator in all aspects. Test results on a number of experimental machines fully support the theory.     

Chopper-controlled wind-driven self-excited induction generators

Two chopper circuit configurations, one with voltage commutation, are shown to be useful for obtaining a controllable DC voltage from wind-driven self-excited pole-changing induction generators. For the case of a resistive load, expressions for the average load voltage and power are derived, and a set of normalized curves relating the voltage ratio and time ratio is drawn. Experimental results on a self-excited induction generator with a 4/6-pole combination using these choppers fully demonstrate the utility of the setup as a whole. Test results on an induction generator controlled by DC choppers demonstrate that any desired load voltage up to a maximum of input voltage can be maintained easily by varying the time period in the case of a load-commutated chopper and the on-off-time ratio in the case of a voltage-commutated chopper     

Single-Winding Single-Phase Inductor Alternator

The mathematical analysis of a single-phase inductor alternator presented here asserts that rotor slot restrictions apply only for alternators with conventional double winding. Schemes using single winding for both dc excitation and single-phase output are developed and their designs are discussed. It is demonstrated that the proposed schemes are superior in performance to conventional schemes. Test results on a number of laboratory size machines fully support the theoretical findings.