Patent ID: 7479757

Claim:
A system comprising: an auxiliary power system for use in a mining machine comprising: an active Insulated Gate Bipolar Transistor device adapted to, when the mining machine is under retard, receive a first AC signal from a traction motor and provide a first DC signal to a DC bus, and thereby function as a rectifier, said active Insulated Gate Bipolar Transistor device adapted to, when the mining machine is not under retard, receive a third DC signal from the DC bus and provide a second AC signal to the traction motor and thereby function as an inverter, transistors of said active Insulated Gate Bipolar Transistor device are switched by an information device; a liquid-cooled heat sink adapted to receive a second DC signal from an active Insulated Gate Bipolar Transistor DC chopper, the active Insulated Gate Bipolar Transistor DC chopper adapted to receive the first DC signal and convert the first DC signal to the second DC signal; a liquid pump adapted to move a cooling liquid over said heat sink; a fan adapted to circulate air to cool the cooling liquid; and applying two active vectors for a specific traction of a sampling interval to operate switches of said active Insulated Gate Bipolar Transistor device.