A system for controlling electrical power generated by a permanent magnet machine coupled to an internal combustion engine includes a central processing unit configured to determine speed of the machine, and compare the machine speed with a predetermined range of machine speeds, a series power switching circuit connected between the machine and a battery, a bus decoupling power switch connected between a voltage bus and the battery, and a bridge switching circuit connected between the voltage bus and the machine and configured to amplify voltage generated by the machine if the machine speed is less than a predetermined value or fall within a predetermined range thereby charging the battery with amplified voltage even at lower machine speeds. The central processing unit selectively connects the bridge switching circuit with the battery by actuating the bus decoupling switch and/or the series power switching circuit depending upon the machine speed.