While discharging a 200uF ( 250 volt charged ) capacitor with resistance of 1 Ohm, what is the highest current the capacitor can handle. Like say we put a few of these in a mixed capacitor circuit. Would they fry up instantly?
I heard from somewhere that in case of pulse power supply, it never happens that things fry up… so.
Like the other responder pointed out if you discharge a capacitor that was charged to 250 Volts through a 1 ohm resistor the peak current will be 250 Amps. But capacitors are not rated for maximum current. Capacitors are rated for Maximum Voltage. A capacitor`s peak discharge current is limited only by the amplitude of the Voltage that it is charged up to and the external impedance that it discharges through. A capacitor may damage a component that it discharges through somewhere in the circuit but a capacitor never damages itself by discharging too much current unless it is charged to a higher Voltage than it is rated at. Remember a capacitor only handles changes in current and not steady state current regardless of whether it`s charging or discharging. i of C = C de/dt. That is to say that if the Voltage across the capacitor is not changing then the capacitor`s current is zero. Of course the stored Voltage across the capacitor is decreasing as the capacitor discharges which accounts for de/dt required for current flow during discharge.
You can see from the formula for i of C that a pulse Voltage which has a very high de/dt would create a very high instantaneous i of C during charge time which could possibly damage a capacitor like you said you heard from somewhere.
Like say you put a few 200uF capacitors in a circuit (for what reason I don`t know) and charge them up to 250 Volts and then switch in a low resistance discharge path for them to discharge through then for sure you are going to create a lot of heat outside the capacitors. But when the discharge is finished the capacitors will be sitting there ready to be charged up to do it again but what ever they discharged through may be burned up and not so ready.
1 ohm means you will get a peak current of 250 amps. That is a lot higher than I would like to see. Using a 100 ohm resistor will be a lot safer.
for one thing, the peak power in that resistor is 62000 watts. You will never find one of that rating.
"put a few of these in a mixed capacitor circuit", you will have to explain further.
References :
Like the other responder pointed out if you discharge a capacitor that was charged to 250 Volts through a 1 ohm resistor the peak current will be 250 Amps. But capacitors are not rated for maximum current. Capacitors are rated for Maximum Voltage. A capacitor`s peak discharge current is limited only by the amplitude of the Voltage that it is charged up to and the external impedance that it discharges through. A capacitor may damage a component that it discharges through somewhere in the circuit but a capacitor never damages itself by discharging too much current unless it is charged to a higher Voltage than it is rated at. Remember a capacitor only handles changes in current and not steady state current regardless of whether it`s charging or discharging. i of C = C de/dt. That is to say that if the Voltage across the capacitor is not changing then the capacitor`s current is zero. Of course the stored Voltage across the capacitor is decreasing as the capacitor discharges which accounts for de/dt required for current flow during discharge.
You can see from the formula for i of C that a pulse Voltage which has a very high de/dt would create a very high instantaneous i of C during charge time which could possibly damage a capacitor like you said you heard from somewhere.
Like say you put a few 200uF capacitors in a circuit (for what reason I don`t know) and charge them up to 250 Volts and then switch in a low resistance discharge path for them to discharge through then for sure you are going to create a lot of heat outside the capacitors. But when the discharge is finished the capacitors will be sitting there ready to be charged up to do it again but what ever they discharged through may be burned up and not so ready.
References :