A Three-Phase Rectifier for Wecs With Indirect Current Control

Abstract

This paper presents a novel Wind Energy Conversion System (WECS) capable of processing the energy from a Permanent Magnetic Synchronous Generator (PMSG) coupled to a three-blade wind turbine and injecting it into the utility power grid. This WECS is composed by two stages: a three-phase rectifier and a single-phase inverter. The ac-dc stage consists of three single-phase bridgeless rectifiers processing the power of each phase of the PMSG separately. The dc-ac stage is composed of a full-bridge inverter with controlled output current. Besides, indirect current control for High Power Factor (HPF) operation is employed, allowing the unification of two important techniques currently available, that are one cycle control (OCC) and selfcontrol (SC). Additionally, a third technique, that comprises the optimum characteristics of both OCC and SC, is proposed and applied to the rectifier stage of the proposed WECS. The proposed WECS and control technique are both validated by experimental results from a 5kW prototype.

Keywords

• grid-connected system
• Indirect current control
• one cycle control
• Power Factor Correction
• selfcontrol
• three-phase bridgeless rectifier