Triple Three-Phase Diode Rectifier-Connected Wound Rotor Non-Overlap-Winding Synchronous Generator for DC Grid Wind Turbine Systems

In the search for non-permanent magnet wind generator solutions, this paper presents a performance evaluation of a wound rotor synchronous generator (WRSG) with a nonoverlapping stator winding for DC grid wind turbine systems. The focus is to compare the WRSG performance when connected to single and triple three-phase rectifier configurations of DC grids, particularly in offshore wind farms, where DC grids are gaining prominence. The evaluation is conducted through simulations using Ansys Maxwell/Simplorer and experimental measurements. Both the simulations and experiments are performed on a WRSG prototype featuring a 16/18 pole/slot combination. The findings present a comprehensive analysis of various performance indicators,including torque, voltage and current waveforms, as well as efficiency. The results show that the triple rectifier configuration has a significant higher efficiency than the single rectifier configuration.

I. Introduction

The use of renewable energy sources, such as wind power, has increased significantly in recent years due to the growing concern for the environment and the need for sustainable energy sources. Wind power systems predominantly use rareearth permanent magnet (PM) generators due to their high efficiency [1]. However, the use of rare-earth materials in these generators poses environmental concerns, production challenges, and cost issues. These challenges have driven research and the industry to explore non-PM generator options for wind energy applications.