An internship at the power system protection department of the transmission system operator TenneT arose my special interest for the field of power system protection. During my master studies I heard several lectures focussing on power system protection. This enabled me to gain a broad overview of the topic. My field of interest is the detection and localisation of earth faults in networks with isolated and resonant earthing, which poses a particular challenge due to the small magnitude of the fault currents. My special focus lies on the transient phenomena accompanying the fault inception. Moreover, I work on further aspects concerning the neutral point treatment of networks, e.g. the modelling and control of arc suppression coils.