Sensored and sensorless scalar-control strategy of a wind-driven BDFRG for maximum wind-power extraction

Abstract

This paper presents a scalar volt per hertz (V/f) control technique for maximum power tracking of a grid-connected wind-driven brushless doubly fed reluctance generator (BDFRG). The proposed generator has two stator windings namely; power winding, directly connected to the grid and control winding, connected to the grid through a bi-directional converter. In order to enhance the performance of the proposed scalar-control strategy, a soft starting method is suggested to avoid the over-current of the bi-directional converter. Moreover, the capability of generator speed estimation for sensorless control is also studied. The capability of the proposed scalar-control technique is validated using a sample of simulation results. In addition, the presented simulation results ensure the effectiveness of the proposed control strategy for maximum wind-power extraction under wind-speed variations. Furthermore, the results show that the estimated generator speed is in a good accordance with the actual generator speed which supports sensorless control capability.

Keywords:

• Brushless doubly fed reluctance generator
• wind-power generation systems
• soft starting
• scalar V/f control
• maximum wind-power extraction
• speed estimation