Patent ID: 7489093

Claim:
An apparatus for producing tractive effort, said apparatus comprising: an energy source adapted for generating a high DC voltage; a motor drive adapted for generating a motor voltage from said high DC voltage; and a motor adapted for producing said tractive effort from said motor voltage, said energy source comprising: a heat engine adapted for generating mechanical power by burning a fuel; an alternator adapted for generating an alternating voltage from said mechanical power; a rectifier adapted for rectifying said alternating voltage and producing a low DC voltage; an energy battery adapted for storing and delivering energy derived from said low DC voltage; and a traction boost converter adapted for boosting said low DC voltage to produce said high DC voltage, said motor drive comprising: a power battery adapted for storing energy and delivering power at said high DC voltage; and a traction converter adapted for generating said motor voltage from said high DC voltage during motoring operation and for generating said high DC voltage from said motor voltage during braking operation; wherein a ratio of the energy storage capacity of said motor drive to the power delivered by said energy source at said high DC voltage is between 0.001 hours and 60 hours.