Hello,
I use triac to control the permanent capacitor motor. I have attached my schematic and two methods I found for cutting signals.
1. power is applied for several continuous half-cycles and then removed for several half-cycles
2. use the dimming method
please help me with their advantages, disadvantages, and their applications or any better way.

 

Generally this type of control is used only with 1ph PSC motors up to 1/2hp. Typically the method 2. (dimmer style) is used.

 

Generally this type of control is used only with 1ph PSC motors up to 1/2hp. Typically the method 2. (dimmer style) is used.

Thanks for reply,
my application is for 300 to 500 watt PSC motors.
I think method 1 has less harmony and zerocross switching is more safe . Is there any limitation or disadvantage for using method 1?
someone says one off them used for torque control and other for speed control but what I find is they are relative to each other.
what's your opinion?

 

Iph motors are generally used in speed control, fans etc, they do not do well in torque mode control, there have been attempts to construct VFD's for 1ph motors, but largely unsuccessful, due to drop out of run at low RPM or under load..
Ver 1 may be better and quieter but probably suffer the same result as above.