A control device for controlling an electric machine with ks windings on a stator and kr windings on a rotor, where ks+kr=n and either ks or kr may be zero, includes an input for receiving commands, an output for outputting control commands to a driver, machine modeling means for modeling behavior of the machine, and decision means connected to the input, output, and machine modeling means for determining the driver control commands. The machine modeling means models behavior of the machine through functional mapping suited for correlating sets of values of electrical and mechanical quantities, sets of values of their total or partial derivatives and/or integral functions with one another. The functional mapping includes an algorithm and/or equation based on at least one state function associated with the electromagnetic field inside the machine and/or based on at least one partial derivative of the state function.