Sensorless Frequency and Voltage Control in Stand-Alone DFIG-DC System

Research output: Research - peer-reviewArticle


A sensorless stand-alone control scheme of a DFIG-DC system is investigated in this paper. In this layout, the stator voltage is rectified by a diode bridge that is directly connected to a dc bus. The rotor side Voltage Source Inverter (VSI) is the only controlled converter required in this system and is directly powered by the same dc-bus created by the stator-side rectifier. Dc voltage and stator frequency are regulated by two independent PI regulators that give the references for inner current controllers implementing field oriented control. As it is capable of creating a stable and regulated dc-bus, this system can be conveniently adopted to supply dc loads or to form a dc grid. Due to the constraint imposed by the stator diode bridge, the DFIG has to operate under a constant stator voltage, and the conventional stator field oriented control implemented in stand-alone ac DFIG must be modified. The paper presents the control structure and the theoretical framework for the controller synthesis. Simulation and experimental validations on a small-scale rig are included.

Bibliographical metadata

Original languageEnglish
Number of pages9
JournalIEEE Transactions on Industrial Electronics
Issue number3
Early online date2 Nov 2016
StatePublished - 2017