—The use of multi-terminal HVDC to integrate wind
power coming from the North Sea opens de door for a new
transmission system model, the DC-Independent System
Operator (DC-ISO). DC-ISO will face highly stressed and
varying conditions that requires new risk assessment tools to
ensure security of supply. This paper proposes a novel risk-based
static security assessment methodology named risk-based DC
security assessment (RB-DCSA). It combines a probabilistic
approach to include uncertainties and a fuzzy inference system to
quantify the systemic and individual component risk associated
with operational scenarios considering uncertainties. The
proposed methodology is illustrated using a multi-terminal
HVDC system where the variability of wind speed at the offshore
wind is included
