New Space-vector hysteresis current control with neutral point voltage balancing applied on three-level VSI for wind power conversion

Abstract

This paper presents a new space-vector hysteresis current control (SV-HCC) with neutral point voltage balancing applied on a three-level NPC-VSI. The last supplies a rotor winding of the doubly fed induction generator (DFIG). The proposed control technique controls the power delivered from the wind generator to the electrical network by controlling the rotor currents of the DFIG. It is based firstly on the detection of area and sector in which the error vector tip of the rotor current can be located, secondly, on the neutral voltage sensing. And then on the application of an appropriate voltage vector among the 27 voltage vectors of the three-level NPC-VSI to accomplish two main goals:

1- Controlling the active and reactive powers delivered by the wind generator to the electrical network.

2- Balancing the neutral point voltage of the three-level VSI.