Maximum power extraction under different vector-control schemes and grid-synchronization strategy of a wind-driven Brushless Doubly-Fed Reluctance Generator

Mohamed G Mousa; S M Allam; Essam M Rashad

doi:10.1016/j.isatra.2017.10.005

Maximum power extraction under different vector-control schemes and grid-synchronization strategy of a wind-driven Brushless Doubly-Fed Reluctance Generator

ISA Trans. 2018 Jan:72:287-297. doi: 10.1016/j.isatra.2017.10.005. Epub 2017 Oct 20.

Authors

Mohamed G Mousa¹, S M Allam², Essam M Rashad³

Affiliations

¹ Department of Electrical Power and Machines Engineering, Faculty of Engineering, Tanta University, Egypt. Electronic address: mohamed.hussien3@f-eng.tanta.edu.eg.
² Department of Electrical Power and Machines Engineering, Faculty of Engineering, Tanta University, Egypt. Electronic address: sm_allam@f-eng.tanta.edu.eg.
³ Department of Electrical Power and Machines Engineering, Faculty of Engineering, Tanta University, Egypt. Electronic address: emrashad@ieee.org.

PMID: 29061484
DOI: 10.1016/j.isatra.2017.10.005

Abstract

This paper proposes an advanced strategy to synchronize the wind-driven Brushless Doubly-Fed Reluctance Generator (BDFRG) to the grid-side terminals. The proposed strategy depends mainly upon determining the electrical angle of the grid voltage, θ_v and using the same transformation matrix of both the power winding and grid sides to ensure that the generated power-winding voltage has the same phase-sequence of the grid-side voltage. On the other hand, the paper proposes a vector-control (power-winding flux orientation) technique for maximum wind-power extraction under two schemes summarized as; unity power-factor operation and minimum converter-current. Moreover, a soft-starting method is suggested to avoid the employed converter over-current. The first control scheme is achieved by adjusting the command power-winding reactive power at zero for a unity power-factor operation. However, the second scheme depends on setting the command d-axis control-winding current at zero to maximize the ratio of the generator electromagnetic-torque per the converter current. This enables the system to get a certain command torque under minimum converter current. A sample of the obtained simulation and experimental results is presented to check the effectiveness of the proposed control strategies.

Keywords: Brushless Doubly-Fed Reluctance Generator; Grid-synchronization strategy; Maximum wind-power extraction; Minimum converter current; Soft starting; Unity power factor; Vector control; Wind energy conversion system.