Excitation commanding for current fed motor drives

摘要

An a-c electric induction motor control system having apparatus for balancing motor air-gap flux against motor stator current in a manner to derive a motor excitation command signal which tends to cause the control system to force the motor to operate on a predetermined torque versus slip frequency characteristic. The motor excitation command signal is utilized to regulate the magnitude of excitation supplied to the motor such that the air-gap flux level assumes a predetermined magnitude as a function of the motor slip frequency. Above motor corner point velocity, the balancing is modified in favor of flux such that the motor is operated in a constant horsepower mode.