The harmonic impedances and voltage source transients model of 12 pulse AC-DC converters for harmonic flow analysis using discrete wavelet transform

This paper presents of harmonics flow analysis with the 12-pulse converters of HVDC link which are harmonic voltage source converter (VSC) in the AC-DC systems. A new fast numerical technique is used with the harmonic domain algorithm to calculate the harmonic impedances of AC-DC converters. The VSC-based HVDC can be used to control terminal bus voltage and balance power exchange among the VSC converters. The presents of harmonic current equations network elements in the harmonic impedances model are calculated by a predetermined equation. The effect of imperfect frequency response of the filters in discrete wavelet transform (DWT) filter banks, and a DWT based algorithm for harmonic analysis of nonstationary power system waveforms. The system case study is the 14 buses system. The results for this condition have show low distortion of voltage and power at all buses these are caused by characteristics of harmonic currents from HVDC converters.