SPEED CONTROL DEVICE OF ASYNCHRONOUS ELECTRIC MOTOR (VERSIONS) Russian patent published in 2011 - IPC H02P27/06 H02M5/275 H02M7/521 B60L9/30 B60L15/06 

FIELD: electricity.

SUBSTANCE: speed control device of asynchronous electric motor includes active rectifier made as per bridge circuit the ac input of which is connected to outputs of secondary winding of network transformer. Capacitance divider in constant voltage circuit of frequency converter is connected to output of active rectifier. Middle point of secondary transformer winding is connected to middle point of capacitance divider in dc circuit of converter. For the purpose of further simplification of the device two phases of asynchronous electric motor are connected to two arms of voltage inverter, and the third phase of asynchronous electric motor is connected to middle point of capacitance voltage divider in dc circuit of frequency converter. Active bridge rectifier of supply voltage is made on two diodes the two in-series connected arms of which are shunted with opposite connected transistors.

EFFECT: increasing output during power supply from single-phase network.

3 cl, 4 dwg