STARTER AND AUTOMATIC SPEED CONTROL SYSTEM FOR PHASE-WOUND ROTOR ASYNCHRONOUS MOTOR

摘要

The invention relates to a starter and automatic speed control system for phase wound rotor asynchronous motors, comprising an electric power equipment consisting in a symmetrical three-plase bridge rectifier (3), connected to the rotor phases of an asynchronous motor (1) through coils (2), a stabilized DCvoltage intermediary circuit connected to the three-phase bridge reversible rectifier (7), the system also comprising an automatic control equipment consisting of a voltage regulator (14), amplifiers (15, 16, 17) which supply imposed values (i R *, i S *, i T *) comparable with the measured values (i R, i S, i T) of the rotor currents, signals being obtained at the output of the hysteresis comparators (18, 19, 20), said signals synthetized in a control grid device (21) will control the static switches of the bridge rectifier (3), the asynchronous motor (1) speed control (n) being performed by comparison with an imposed value (n *), in a speed regulator (22), by limiting the continuous current in the intermediary circuit to an imposed value (i C *), by means of a current regulator (23) which actuates a control grid device (24) for controlling the thyristors of the three-phase bridge reversible rectifier (7) which is connected to the network phases through an adapter transformer (8) which permits the recovery of the slide energy into the network