ELECTRICAL POWER SYSTEMS

Electrical power systems for distributing electrical power in arrangements comprising one or more gas turbine engines 101 are described. One such electrical power system comprises: one or more rotary electric machines 111-113, each mechanically coupled to a gas turbine engine spool; a set of converter circuits 203 connected to the one or more rotary electric machines 111-113 for conversion between alternating current (ac) and direct current (dc), wherein the one or more rotary electric machines 111-113 and the set of converter circuits 203 are arranged to output a number R ≥ 2 of dc power channels 206-209, each dc power channel 206-209 having a respective index r = (1, ..., R); and a group of N dc load channels 400-1200 connected to the R dc power channels 206-209 by a switching arrangement 410-1210, wherein N > R and each dc load channel 400-1200 has a respective index n = (1, ..., N). The switching arrangement 410-1210 is operable to connect a number Q ≥ 1 of the N load channels 400-1200 to at least two different power channels of the R power channels 206-209. The system further comprises a controller configured to control the operation of the switching arrangement 410-1210 to control which of the power channels 206-209 the N load channels 400-1200 receive electrical power from.