how many capacitor that i used?also specify formula for calculating filter capacitor...
It all depends on how much current you want to draw. You also need a way to get 270 V DC. If you just use a rectifier circuit it will give you a peak of 325V, which might not be good for a 270V DC motor.
A full wave bridge is likely best surge rated about twenty times the current rating of the DC motor, unless you have a current limiting resistor, perhaps 1 ohm rated 100 watts. Try about 2 microfarads rated at least 330 dc or ac volts. That will likely put about 240 volts on the motor, while it is running at light load. If so, you will need more capacity, perhaps more than 100 microfarads for a large dc motor. You should increase capacity until you get to about 190 volts at light load as the voltage will drop at full load on the motor. You likely need at least two heat sinks for the full wave bridge rectifier. Neil
Hi you could always use an auto transformer and put the motor on the output terminal and the input on the ground end and wiper. to control it which removes the need for a capacitor at all.
You need more than a capacitor. If you rectify 230 VAC you will get a peak of 325 volts, so you need some type of controller (or power supply) that reduces it to 270 VDC.
