A Novel HVDC Transmission System Based on Z-Source Converter

In this paper, for improving performance of High Voltage Direct Current (HVDC) system, a new HVDC transmission line based on Z-Source Converter is proposed (HVDC-ZSC). Proper controllers in order to follow active and reactive power demands accurately, and also regulate the terminals’ voltage, are designed. Traditional HVDC systems used current source converters and voltage source converters, have some limitations and failures. In the proposed system, unlike conventional HVDC system, ZSC as the building block instead of voltage source converter (VSC) and current source converter (CSC) have been used. The advantages and excellence of this converter have overcome some disadvantages and limitations of HVDC converters including commutation failure, lack of buck and boost of voltage. The simulation results, held by MATLAB/Simulink, indicate that the application of ZSC has improved some of HVDC characteristics such as short-circuit current level, voltage sag due to fault, output voltage control and lower harmonics generation.