The continued growth of renewable energy generation increases the mismatch between where and when electricity is produced and consumed, creating a need for efficient and flexible transmission technologies. High-voltage direct current (HVDC) transmission is well suited for this due to its low losses and better controllability. While HVDC systems are mainly used as point-to-point links today, future systems are expected to include meshed multi-terminal HVDC grids to improve reliability and flexibility. However, the short-circuit behavior is more complex in meshed DC networks. In such systems, DC circuit breakers are used to isolate faulty lines while keeping the rest of the grid in operation. The short-circuit currents in these networks is therefore an important aspect to consider for system planning and design. The DC steady-state short-circuit current is a key parameter in the early design phase, as it supports equipment sizing, system dimensioning, and overall grid development. Simplified, non-iterative methods for estimating the DC steady state short circuit current of VSC based HVDC systems have been proposed in the literature, mainly for point-to-point configurations. Their applicability to meshed HVDC grid topologies, where multiple converters and current paths interact, has not yet been sufficiently validated in detail. This master’s thesis aims to validate the applicability of the existing non iterative calculation method for determining the DC steady state-short circuit current in VSC based meshed HVDC grids. Depending on the results new methods should be explored.

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