Comparative Analysis of Fault Detection for HVDC Transmission System Using Wavelet Transform Based on Standard Deviation

Electrical losses and capital cost are two important factors for an efficient transmission of electrical power from generation station to load center. High Voltage Direct Current (HVDC) for its high power carrying capacity is the most suitable option to transmit electrical power leading to low electrical losses and capital cost of the system. However, there is possibility of severe AC and DC faults because of its high power transmission capacity. Fault penetration is more severe in HVDC system due to the power electronics based converters and proper protection is required for the power converters and HVDC transformers owing to their high capital cost. In this work, a simple time-frequency analysis technique is proposed for the identification of HVDC faults using MATLAB/Simulink software. The simulation results show that the most efficient mother Wavelet Transform (WT) based on the standard deviation occurs at the 6th level of decomposition of fault signal to detect the DC fault, symmetrical and asymmetrical faults.