There is provided an electrical assembly (20) comprising: a voltage sourced converter (22) for connection to an AC network (30); a controller (40) programmed so that, responsive to detection of a fault in the AC network (30), the controller (40): obtains a first set of voltage and current measurements taken at an interface connection point (PCC) between the voltage sourced converter (22) and the AC network (30); after obtaining the first set of voltage and current measurements, change operation of the voltage sourced converter to inject a modified fault current, and then obtain a second set of voltage and current measurements taken at the interface connection point (PCC); using the first and second sets of voltage and current measurements, determine operating parameters of the voltage sourced converter (22) for injecting a target fault current having a target phase angle that is the same, or substantially the same, as a phase angle of a reference fault current that would have resulted from operation of the voltage sourced converter (22) in accordance with pre-fault steady-state voltage phase and magnitude values; and operate the voltage sourced converter (22) in accordance with the determined operating parameters so as to inject the target fault current at the target phase angle.