Requirement analysis of protection of future HVDC grid: transmission side

Abstract

Today's electric grid is mostly based on alternating current (AC), as well as the

loads. The advance of voltage source converter-based high-voltage direct current

(HVDC) transmission systems makes it possible to build a multi-terminal HVDC

grid. Compared with the HVAC grids, active power conduction losses are

relatively low, and reactive power conduction losses are zero in an HVDC grid.

For these reasons, there is significant consideration for DC grid, but lots of open

points remain to be answered. One of the most important and pivotal topics for

such DC grid, is the protection, for safeguarding the grid against faults. As there is

no active DC transmission grid currently (mostly there is point-to-point

connection), future protection systems would be needed to be researched and

developed. A thorough analysis of the technical requirements is a key point. This

MSc thesis is aimed for detailed investigation about the requirements of the

protection of future HVDC (HV: 69-765 kV range) grids for the transmission side.