METHOD OF ELECTRIC POWER PLANT COOLING SYSTEM FAN DRIVE MOTOR CONTROL Russian patent published in 2019 - IPC G01R31/00 H02K11/00 

FIELD: machine building.

SUBSTANCE: disclosed is a method of electric motor controlling. Full voltage of the on-board network of the power plant is supplied through the interface of the speed setting device to the electric circuit of the electric motor within the limits of the time period limited by regulations. Subsequent supply is supplied through the speed setting interface to low voltage, the amplitude value of which is less than the value of the full-circuit voltage of the on-board network. Value of regulated period of time is set equal to time interval during which there is stabilization of amplitude of varying current in electrical circuit of electric motor to level, which is typical for steady-state operating mode of electric motor at preset power supply mode and temperature. Feeding electric motor of reduced voltage into electric circuit is also performed during specified period of time, thereafter, voltage amplitude of the on-board circuit and average amplitude of voltage applied to electric motor circuit are measured. Then measured voltages amplitudes are compared with their pre-set values. In case there is no discrepancy between measured and pre-set values of voltage amplitudes, depending on state of control subject of speed setting device, or prolongation of supply to electric circuit of electric motor of reduced voltage reached at previous stage of amplitude, or its further reduction is performed, or electric motor is switched to supply with full voltage of on-board network. In case of discrepancy between measured and pre-set values of voltage amplitudes there performed is comparative, relative to preset values, estimation of criticality of discrepancies and depending on the obtained estimate either the fault indicator of the electric motor is switched on, or the fault indicator is switched on and the electric motor is de-energized.

EFFECT: providing start-up of electric motor at maximum torque, temperature stability of cooled equipment, prevention of electric motor overheating in case of freezing of fan impeller after shutdown of power plant.

1 cl, 3 dwg