INDUCTION MOTOR CONTROL STATION Russian patent published in 2003 - IPC

FIELD: submersible and other pump-motor units for oil and water extraction. SUBSTANCE: supply mains voltage is rectified in control station by means of controllable rectifier, fed to filter, and is inverted into three- phase voltage by means of inverter due to pulse-width modulation. Analog signals picked off inverter input current sensor, inverter input voltage sensor, inverter switches inrush current sensors, output current sensors, ground detector, thermal gage system, and level gage are supplied to matching device of microprocessor control unit. Microprocessor control unit generates control signals in case at least one of parameters of induction motor under control occurs beyond limits specified by settings or design conditions for reliable functioning of control station and induction motor it controls which arrive at inputs of rectifier control unit and at control inputs of inverter to bring these parameters to normal values. EFFECT: enhanced reliability and enlarged functional capabilities of control station. 4 cl, 2 dwg