Dynamic Fault Analysis for HVDC Systems with ac System Representation

Transient valve currents are derived for rectifier short circuits with consideration of transient control behavior, and filter and ac system representation. A comparison is made between connection of the filters on the ac side and tertiary of the covnverter transformer. The valve currents are also analysed for different types of singly-occurring and repetitive commutation failures. The analysis, in each case, has been processed by dynamic digital computation and is considered to be of particular relevance to the current surge ratings of thyristor valves within HVdc converter installations.