Application of Thyristor Bridge-Type Non-Superconducting FCL with Buck Series Charging to Improve the FRT Capability of the DFIG System

Abstract

Wind power generation is observing a significant use of doubly-fed induction generator (DFIG) due to its improved efficiency, but the converter used in the configuration is sensitive to the presence of a fault in the grid. This paper presents a fault ride-through (FRT) configuration, which includes a thyristor-based bridge-type non-superconducting fault current limiter (ThyBT-NSFCL) augmented with a buck converter. It has been observed that the proposed topology works fine under a temporary symmetrical fault. The analytical analysis has been carried out to observe the operating principle of the proposed ThyBT-NSFCL under both normal and fault conditions. A comparative study with other topologies such as switched impedance transformer-type non-superconducting fault current limiter (TT-NSFCL), series dynamic breaking resistor (SDBR), and without any current limiter (WCL) have been done to show the effectiveness of the proposed topology. The simulation results show that the proposed ThyBT-NSFCL is a better fault current limiter as compared with other limiters like TT-NSFCL, SDBR, and WCL. The simulation of the proposed ThyBT-NSFCL connected in series with a DFIG system is carried out using PSCAD/EMTDC software. The performance of the proposed topology is quite good, and it can be used as a reliable limiter for future wind energy applications.