Transient Based Protection for HVDC Lines Using Wavelet-Multiresolution Signal Decomposition

This paper presents a new high-speed and credible protection technique for HVDC line. In the technique, wavelet-multiresolution signal decomposition technique is used to analyze the transient voltages generated by the faults. The technique can discriminate between faults inside the HVDC line and the outside ones reliably. Furthermore, an approach to distinguish lightning strokes from faults is also presented. Extensive simulations of CIGRE standard HVDC system and the actual CSG HVDC system prove the proposed techniques effective and reliable