GATE-CONTROLLED MOTOR Russian patent published in 1997 - IPC

FIELD: electric drives of sound recorder tape transports. SUBSTANCE: the gate-controlled motor uses a rotary frequency changer with an inductor employing permanent magnets 2 and an armature winding, whose sections are connected to the output of the frequency changer made as a voltage inverter, logical control unit, comparators, two groups of integrating circuits and voltage limiters. The integrating circuits and the voltage limiters provide for generation of signals with a duration of 180 deg and shifted relative to one another by 120 deg at the output of the comparators and symmetrical relative to the rotation emf signal. Under the action of these signals the logical control unit provides for alternate switching of the gates of the anode and cathode groups of the frequency changer periodically connecting the armature winding sections to the power source. The motor starts running in the synchronous mode. During running of the motor a rotation emf is set up in the armature winding sections accelerating the processes of switching of the comparators. The motor is changed over to the position switching mode. In the rotary speed stabilization mode, depending on the load, the control signal applied to the additional input of the frequency changer is changed. Connection of the integrators to the inputs of the comparators makes it possible to maintain symmetrical operation of the comparators at different control currents relative to the rotation emf signal. EFFECT: reduced pulsation of electromagnetic torque, knocking and enhanced service life of the motor. 9 dwg