Design and optimization of a Low-RPM Neodymium permanent magnet synchronous generator for two-stage vertical-axis wind turbines in low-speed applications

Abstract

The rising global energy demand and environmental impact of fossil fuels intensify the search for efficient renewable solutions. Small-scale vertical-axis wind turbines (VAWTs) in constrained environments (e.g., highway dividers) offer potential but face inefficiencies with conventional generators at low wind speeds. To address this, a low-rpm Permanent Magnet Synchronous Generator (PMSG) is proposed for operation at 50–900 rpm, aligning with the operational speed range of the VAWT in this study. A 4-pole, 24-slot configuration generator has been designed in ANSYS Maxwell to enhance induced voltage while minimizing cogging torque. Results demonstrate that the proposed generator outperforms conventional dynamos such as brushed DC generators and existing PMSGs in both voltage and current output. Simulations confirm a voltage output of 89.57 V and current of 3.98 A at 250 rpm, outperforming conventional brushed DC generators (conventional dynamos) by 300% in terms of voltage output. The generator operates without external excitation, ensuring higher efficiency and reliability in low-torque applications. This work offers a viable solution for decentralized wind energy generation.