Electrical Power System Converter Control

An electrical machine with a rotor coupled to a drive shaft of an engine; a DC electrical network; a power electronics converter connected, on a DC-side, to the DC electrical network, and, on an AC-side, to the electrical machine, the power electronics converter comprising a plurality of transistors and associated diodes connected in anti-parallel with the transistors; and a controller configured to control switching of the transistors so that the converter either inverts DC power to AC power or rectifies AC power to DC power. The controller is further configured, responsive to a determination that there is a fault in the DC electrical network, to operate in a fault mode in which the controller controls the switching of the transistors so that a fault current is shared between the transistors and the associated diodes.