On the short circuit current contribution of HVDC Light

Voltage source converter (VSC) based HVDC transmission systems are available in the market for power rated between a few MVA to a few 100s of MVA. The new system results in many application opportunities, and new applications in turn bring up new issues of concern. This paper presents a comprehensive investigation on one of the concerned issues, which is the contribution of HVDC Light to short circuit currents. Different AC network conditions, load conditions and fault types are considered under different operation conditions and control modes. Results from simulations with complete control functions as in real systems are presented and discussed. The associated control and protection strategy is also discussed. Finally, a comparison is provided between the HVDC Light and conventional HVDC, the SVC and the STATCOM regarding the impact on the short circuit current.