Patent ID: 7719138

Claim:
A two-source series inverter system, the system comprising: a first voltage source; a second voltage source; an inverter having a first DC input, a second DC input, AC outputs, and first control inputs, wherein the AC outputs are configured to be coupled to a load, the load comprising an AC electric machine that provides power to a powertrain of a vehicle; a voltage combiner having a second control input, the voltage combiner being connected to the first DC input and the second DC input, and coupled to the first voltage source and the second voltage source; and a controller coupled to the first control inputs and the second control input, the controller being configured to receive first feedback signals and second feedback signals from the inverter and the voltage combiner respectively, and configured to control current flow through the voltage combiner and the inverter, wherein: the controller is configured to operate the inverter and the voltage combiner to control flow of a recharging current from the inverter through the voltage combiner to the first voltage source; a first electrical current flows from the first voltage source to the inverter through the voltage combiner; and a second electrical current flows from the second voltage source to the inverter through the voltage combiner.