Control device for plurality of rotating electrical machines

A control device for a rotating electrical machine system having a plurality of rotating electrical machines (1, 5) is provided with a single current control circuit (8) and a controller (12). The controller (12) sets an operating point ( omega m, Tm) of at least one rotating electrical machine of the plurality of rotating electrical machines (1, 5), and sets the current for each rotating electrical machine so that one of the efficiency of the current control circuit (8) and the overall efficiency with respect to all the rotating electrical machines (1, 5). The controller (12) controls the current control circuit (8) so that the current control circuit (8) supplies a composite current to all rotating electrical machines, the composite current combining the set current for each rotating electrical machine.