Motor drive circuit for stable speed control using negative feedback method

Motor drive circuit for stable speed control using negative feedback method

Shown is a motor drive circuit that uses negative feedback for steady speed control . The AC 220 V voltage is output through bridge rectification to about 300 V DC voltage, which supplies power to the DC motor
after passing through the current limiting resistor and adjusting transistor VTI . ICl TA 7165 P is used as a speed error detection amplifier. Pin ⑥ is the reference voltage. Pin ⑦ is connected to a 5 Q resistor. When the current changes, the voltage of pin ⑦ will change. After being amplified by IC1, it controls the base of VT3, so that VT3 controls VT2 and VT1, and achieves speed stabilization by controlling the output voltage of VT1.