<div class="htmlview paragraph">The combination of a high-speed prime mover and wide range of wheel speeds in an off-the-road vehicle makes an electric system appear attractive for driving the wheels. An electric drive system is easily reversible, can apply power independently to each wheel, and lends itself to various types of electric and automatic control.</div> <div class="htmlview paragraph">One type of drive system that represents a good compromise between the features of a-c and d-c drives is the system using a wound rotor induction motor and a static rotor circuit inverter connected to pump power back to the stator line. This system has the control characteristics of a d-c system and requires a relatively trouble-free type of static inverter for its operation. Work has been done with this system for cranes and other industrial applications, but not for vehicle drives. The characteristics and application of the drive to off-the-road vehicles are treated as an example of a possible approach to the electric drive problem.</div>