Modelling Accuracy Requirements for HVDC Protection Design Studies

Advancements in Multi-terminal HVDC systems necessitate complex protection systems, typically including HVDC circuit breakers (DCCBs). Protection system design and component sizing for these systems are not straightforward and require (extensive) EMT studies. For these EMT studies, several reduced HVDC component simulation models could be used, each with an associated level-of-detail and accuracy. The (in)accuracy of HVDC component models directly impacts the outcomes of the EMT studies. This paper aims to shed light on the accuracy requirements for component simulation models, e.g., converter models, that need to be considered for protection studies such as DCCB sizing. To achieve this, a method for determining accuracy requirements based on cost and performance is presented, providing a guideline for selecting models. Different converter models are then compared for several system parameters and fault parameters to determine their use in protection design studies.