Power Converter Schemes for Small Scale Wind Energy Conversion Systems - Review, a Systematic Classification Based on Isolation Transformer and Generator Side Rectifier

Abstract

Permanent magnet synchronous generators used in small scale wind generating systems connected to the grid employ various types of power electronic converters. This paper reviews and gives a systematic classification of many power converter topologies available in the literature based on the electrical isolation between the generator and the grid. Emphasis is given on the type of rectifier used on the generator side. Most of the available converters use line-frequency transformer isolation and it is shown that they can be classified into three types. Based on the available high-frequency transformer isolated ac-dc converters, we have classified them into five schemes suitable for wind energy conversion system applications that can reduce the size, cost and improve the overall performance of such converters. In particular, two single stage soft-switched ac-dc converters have been discussed.