a slip recovery system for a wound rotor induction motor is disclosed in which first and second inverters , connected in series , are coupled to the rotor of the induction motor . a switch is arranged in parallel with the second of these inverters , the switch being in the open position during starting and stopping of the motor , and being closed to short out the second inverter during normal running conditions . thus , the first inverter need have only a voltage rating of such magnitude so as to satisfy the expected operating range for the wound rotor , while the second inverter need have only a voltage rating of sufficient magnitude to satisfy the additional capacity requirements for stopping and starting service . thus , lower rated inverter components may be used with lower initial costs as well as concomitant lower operating costs .