METHOD OF PROPELLER ELECTRIC DRIVE VOLTAGE CONVERSION AND PROPELLER ELECTRIC DRIVE TO THIS END Russian patent published in 2013 - IPC B63H23/24 H02P9/00 

FIELD: transport.

SUBSTANCE: invention relates to ship power plants. Proposed method proceeds from matching supply voltage, rectifying matched voltage and inverting rectified voltage. Tolerances for voltage, current and rate of their change are set. Supply voltage is inverted prior to starting its connection. Inverted voltage reduced to tolerable supply magnitude is connected. Supply voltage is controlled to control inverted voltages and phase currents. Rates of the change are calculated as time derivatives. Said rates are adjusted by made measurements and calculations. In compliance with aforesaid tolerances, supply voltage conversion is terminated when preset magnitudes are reached. Rectified voltage iv inverted to control propeller drive in compliance with loaded algorithm. Propeller drive comprises power supply, matching transformer, frequency inverter with DC link and inverter, propeller motor, frequency inverter control unit and voltage inverter with power unit with thyristors, transducers of voltage and phase current, and controller. Power unit input is connected with voltage source. Voltage transducer power unit output is connected to matching transformer input. Inputs of voltage and current transducers are connected to power unit outputs while their output are connected to controller input. Controller another input is connected to frqencucy inverter control unit output. Controller outputs are connected to power unit thyristor control inputs.

EFFECT: ruled out direct connection of propeller drive to ship electric system on switching on of power.

2 cl, 1 dwg