Power sharing control in VSC based MT-HVDC for integration of off-shore power generation

Voltage Source Converter (VSC) based multi-terminal HVDC transmission system is an effective and reliable way for integrating off-shore wind power generations with onshore AC grid. In this paper, decoupled control of active and reactive power flow is established by modelling VSC controllers in synchronous d-q reference frame. A four terminal VSC-HVDC system is developed in PSCAD/EMTDC and simulated to observe voltage margin and voltage droop control. Simulation results show robust performance of the MT-HVDC system during normal as well as system disturbance condition. Power sharing coordination between grid side converters and DC link voltage regulation are done without any communication link which is an important aspect of using VSC based HVDC.