DIRECT CURRENT ELECTRIC DRIVE Russian patent published in 2000 - IPC

FIELD: alternating current power supply equipment. SUBSTANCE: device provides regulation of rotation frequency of direct current electric motors, which are supplied from alternating current mains. It has collector direct current electric motor, rectifying bridge, by-pass and isolating diodes, power gate, voltage stabilizer, voltage divider, active low-pass filter and rotation frequency setter. In addition device has low-pass filter, comparator, gate, voltage divider, diode and current detector, which output is connected through low-pass filter to direct input of additional comparator, which inverting input is connected to output of rotation frequency setter through additional voltage divider. Output of additional comparator is connected to both input of additional gate and direct input of comparator through diode. Output of additional gate is connected to input of power gate. EFFECT: increased reliability of electric drive. 1 dwg