Investigations on Two-lead and Three-lead Rotor Connections of Doubly Fed Induction Generator

The doubly-fed induction generator (DFIG) has conventionally been put to use with multi-wattage wind turbines to obtain a sophisticated grid-connected network. This configuration is usually put to use for directly feeding power to grid-connected loads. In this paper, a DFIG with DC excited rotor has been implemented to obtain a novel control strategy which is easier to implement and exploit. The novelty aspect of this work concerns proposing and providing comparison and investigation of two topologies: two-lead and three-lead DFIG connections. These two strategies yield a near-perfect sinusoidal waveform at the stator with very low total harmonic distortion (THD) at steady state. The results presented in this work validate that the usage of DFIG with rotor excited via DC is a simple and easy method for exploiting wind energy. The two-lead and three-lead DFIG configurations can be extensively put to use in Asian countries to boost renewable energy production, thereby decreasing pollution. Increased tapping of the power from wind will result in a reduction in the potential hazards to the environment due to conventional methods of electrical energy generation.