An electric power supply system for an aircraft includes: a first electric source and a second electric source coupled together to supply electric power to a set of electrical loads, and a controller configured to acquire a piece of information on the current electric consumption consumed by the set of electrical loads; acquire a piece of information corresponding to a target ratio of the distribution, between the first and second electric sources, of the current electric consumption consumed by the set of electrical loads; perform frequency filtering of the current electric consumption to determine a transient consumption portion of the current electric consumption; determine control setpoints for the first electric source and for the second electric source in accordance with the target distribution ratio and with the transient consumption portion; and apply the control setpoints to the first and second electric sources.