the counter-EMF of the motor also decreases. This results to a voltage increase in R2-P1 and C3 causing the triac to be triggered earlier and the speed increases accordingly. Another version found ...

Instead of using a 3-wire control circuit to start and ... the silicon-controlled rectifier, triac, and insulated gate bipolar junction transistor, have allowed the VFD to become the method of choice ...

This SCR phase control works much like the common TRIAC dimmer, but has numerous advantages including increased current capability, robustness and absence of minimum voltage “snap-on.” A complementary ...

The motor-speed-control circuit in the figure shows an SG3524 pulse-width-modulation (PWM) IC, U2, driving the high side of a motor through a p-channel FET, Q1. The motor terminal voltage is more ...