Fault-Tolerant Voltage Source Converter for Wind-Driven Doubly Fed Induction Generator Connected to a DC Load

Abstract

This paper presents a fault-tolerant Voltage Source Converter (VSC) for Field Oriented Control (FOC) of a stand-alone Doubly Fed Induction Generator (DFIG) connected to a DC load. In the proposed topology, the stator of the DFIG is connected to a DC load through a diode rectifier, while the rotor is connected to the DC load through a VSC. This topology allows the integration of DFIG in the hybrid system with other sources of production and storage, such as photovoltaic system, connected to the same DC bus. The fault-tolerant VSC consists in incorporating a fourth leg to replace the faulted leg. A fault detection scheme for switch device open-circuit faults is proposed in this study. The novelty of this method consists in analyzing the rotor currents within normal and faulty operating modes. Simulation results are presented for a 3.7[Formula: see text]kW DFIG-DC system with single open-circuit faults that validate the methods presented in this study. The effectiveness of the proposed fault detection method has been validated experimentally by using dSpace DS1104 control board based on TMS320F240 real time Digital Signal Processor (DSP).