Medha Servo Drives Pvt. Ltd. Supplies Auxiliary Inverter Motor. Medha Servo Drives Pvt. Ltd. Is an ISO 9001:2000 recognised company. Auxiliary Inverter Motor is applied for control and IGBT semiconductor power devices in inverter. These AC Motor-Inverter combinations are a good retrofit alternative for failure prone and high maintenance DC Motors used for the same functions in older locomotives and takes DC supply from locomotive batteries and provides required sinusoidal supply to 3-phase AC motors.