Control for vehicle electric drive system

A vehicle electric drive system includes an internal combustion engine (12), an electric motor/generator (14) driven by the engine (12), a first inverter/rectifier (16) coupled to motor/generator (14), a buss (18) coupled to the first inverter/rectifier (16), a second inverter/rectifier (20, 22) coupled to the buss (18), and a traction motor/generator (24, 28) coupled to an output of the second inverter/rectifier (20, 22), an operator speed control member (62), and a controller (21, 23) coupled to the second inverter/rectifier (20, 22) for controlling a current output of the second inverter/rectifier (20, 22) as a function of a position of the speed control member (62). Also included is an operator controlled foot pedal (50) and a transducer (52) coupled to the foot pedal (50) and generating a signal representing foot pedal position which is supplied to the controller (21, 23). The controller (21, 23) limits current supplied by the second inverter/rectifier (20, 22) to the traction motor/generator (24, 28) to a limit current as a function of the transducer signal. The controller (21, 23), foot pedal (52) and transducer (52) cooperate to vary the limit current in response to movement of the foot pedal (50). A spring (54) biases the foot pedal (50) to an upper limit position. The controller (21, 23) causes the second inverter/rectifier (20, 22) to supply to the traction motor/generator (24, 28) a maximum amount of current, (such maximum current being a function of the foot pedal position), but not more than that required to achieve the speed commanded by the speed control (62).