A Low Cost Front-End Converter With Maximum Power per Ampere for Rooftop Wind Turbines

Abstract

Small Permanent Magnet Synchronous Generators (PMSGs) are widely used in small rooftop wind turbines. In order to inject the electric power generated by the PMSG, into the grid, a back-to-back AC/DC/AC converter is required. In this paper, a low cost with high efficiency converter is proposed for the rectifier stage to obtain the maximum power per ampere of PMSG. This structure based on Discontinuous Conduction Mode Single-Ended Primary Inductor Converter (DCM SEPIC) with a single power electronic switch, proposes a converter which is cost-effective and suitable for the small wind turbine used in residential applications. Furthermore, other advantages of the proposed converter include obtaining maximum power delivered per ampere using a simple control method and reducing the size of converter inductive filter by exploiting the PMSG internal synchronous reactance as part of the filter. Unlike the conventional DCM Boost rectifiers, the proposed converter has a continuous input current, which results in lower PMSG conduction loss. Operation principles and various operating modes of this converter are discussed in detail in this paper and verified by closed-loop simulation and experimental results for a 500W/200V prototype.

Keywords

• Micro wind generation
• permanent magnet synchronous generator (PMSG)
• power factor correction (PFC)
• single-ended primary inductor converter (SEPIC)