초록 ▼

A system for controlling the operation of an alternating current induction motor having windings supplied by electrical power from the polyphase alternating current source includes a load commutated inverter circuit which is connected between the power source and the induction motor for furnishing e

A system for controlling the operation of an alternating current induction motor having windings supplied by electrical power from the polyphase alternating current source includes a load commutated inverter circuit which is connected between the power source and the induction motor for furnishing electrical power to the motor. Controllers responsive to a command signal and a feedback signal indicative of motor operating parameters control the operation of said load commutated inverter circuit. There is further provided a fixed capacitor circuit connected between the windings of the motor for supplying reactive volt amperes (VARs) to said load commutated inverter circuit and said motor. Finally, there is provided a variable VAR generator connected between the motor windings for supplying VARs to said load commutated inverter circuit and said motor in response to the output of a third feedback control path which is also responsive to a command signal and prescribed operating parameter(s) of said load and/or said commutated inverter.

대표청구항 ▼

A system for controlling the operation of an alternating current induction motor having windings furnished with electrical excitation from a polyphase alternating current power source comprising: (a) a controllable load commutated inverter circuit, including a controllable source side alternating cu

A system for controlling the operation of an alternating current induction motor having windings furnished with electrical excitation from a polyphase alternating current power source comprising: (a) a controllable load commutated inverter circuit, including a controllable source side alternating current to direct current converter and a load side direct current to alternating current converter interconnected by a direct current link, connected between said power source and said induction motor, said load commutated inverter circuit having an output furnishing an output current having real and demagnetizing polarity exciting current components to said motor; (b) a capacitor circuit connected to the motor windings and to the output of said load commutated inverter circuit for furnishing leading exciting current to said motor and said load commutated inverter circuit; (c) a controllable VAR generator connected to the motor windings and to the output of said load commutated inverter circuit for furnishing exciting current to said motor and said load commutated inverter circuit; (d) means to generate a motor operation command signal; (e) a first control path including means responsive to said motor operation command signal for controlling the operation of said alternating current to direct current converter; (f) a second control path responsive to said motor operation command signal for controlling the operation of said direct current to alternating current converter; (g) a third control path for controlling the exciting current furnished to said motor by said VAR generator, said third control path including, (1) means to generate an exciting current command signal proportional to the amount of exciting current required for a desired motor operation; and, (2) means responsive to said exciting current command signal to control said VAR generator.