Phase-change capacitor issue
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Ordinary electric actuators use commutation capacitors to achieve forward and reverse rotation. What kind of capacitors are these commutation capacitors? How does it work? Thank you
My simple explanation: The motor in the electric actuator has two windings. At a given moment, one winding is connected to a capacitor, while the other winding is not connected to any capacitor. These two circuits are then connected in parallel, with 220V AC applied across them; this causes the motor to rotate in one direction. When the capacitor is removed from one winding and connected to the other winding, and these two windings are connected in parallel, the motor rotates in the opposite direction. By selecting the appropriate wiring through the corresponding controller or servo amplifier, it is possible to transfer the capacitor from one winding to another, thereby enabling the motor to rotate in either direction and achieving the purpose of regulating the valve. There is a phase-shifting issue here. The capacitor used should be an AC capacitor, with a voltage rating that is higher than the rated voltage of the motor; for motors operating at 220V AC, the capacitor should have a rating of at least 250V.