help need to calculate the out put current of a capacitor
rajheman, Wed Sept 14 2016, 11:52PMplease tell me how to calculate the out put current of a capacitor as mentioned in this picture af power labs railguns power supply
Re: help need to calculate the out put current of a capacitor
hen918, Thu Sept 15 2016, 09:06AM
The easiest way is to use Barry's coilgun simulator:
It does require you to use an older browser and enable unsigned java to run in your system settings
hen918, Thu Sept 15 2016, 09:06AM
The easiest way is to use Barry's coilgun simulator:
It does require you to use an older browser and enable unsigned java to run in your system settings
Re: help need to calculate the out put current of a capacitor
Blackcurrant, Thu Sept 15 2016, 03:08PM
Cap Bank= 3088uF ESR14.7mOhhm ESL1uH @3200V
so for max power out the load must be about 14.7mOhm = about 100kA
I would use a spice program to see the current discharge curve. ie SIMetrix
there's 4 strings of 8 caps so 100/4=25kA
I would think this would be very cruel to the caps though
Blackcurrant, Thu Sept 15 2016, 03:08PM
Cap Bank= 3088uF ESR14.7mOhhm ESL1uH @3200V
so for max power out the load must be about 14.7mOhm = about 100kA
I would use a spice program to see the current discharge curve. ie SIMetrix
there's 4 strings of 8 caps so 100/4=25kA
I would think this would be very cruel to the caps though
Re: help need to calculate the out put current of a capacitor
klugesmith, Thu Sept 15 2016, 10:55PM
Took a while to get Barry's coilgun simulator working here, for the first time in a few years. Sam's numbers don't add up, which is not surprising. (He's a gifted young man, but was a lot younger in 2003).
An ESL value of 1 uH would be very significant. Here's a simulated discharge limited only by cap-bank ESR and ESL -- it takes much longer than 62 us.
The peak power to the load in that case is exactly zero, because there's no voltage drop in the ideal discharge switch.
Following Blackcurrant's suggestion, I added another 14.7 mΩ in series to represent a "real impedance" matched load.
Now half of the stored energy goes to the load, and half is dissipated inside the cap bank. For the load to get a bigger share of the energy, it needs to have a higher resistance and the transfer needs to take more time.
klugesmith, Thu Sept 15 2016, 10:55PM
Took a while to get Barry's coilgun simulator working here, for the first time in a few years. Sam's numbers don't add up, which is not surprising. (He's a gifted young man, but was a lot younger in 2003).
An ESL value of 1 uH would be very significant. Here's a simulated discharge limited only by cap-bank ESR and ESL -- it takes much longer than 62 us.
The peak power to the load in that case is exactly zero, because there's no voltage drop in the ideal discharge switch.
Following Blackcurrant's suggestion, I added another 14.7 mΩ in series to represent a "real impedance" matched load.
Now half of the stored energy goes to the load, and half is dissipated inside the cap bank. For the load to get a bigger share of the energy, it needs to have a higher resistance and the transfer needs to take more time.
Re: help need to calculate the out put current of a capacitor
rajheman, Tue Sept 20 2016, 04:09PM
Thanks every one for giving me your valuable suggestions.
dear sir hen918 i was unable to run Barry's coilgun simulator in my laptop which has internet explorer 8 with java version 8 updated 101.
can u plz suggest me how to run the simulator
rajheman, Tue Sept 20 2016, 04:09PM
Thanks every one for giving me your valuable suggestions.
dear sir hen918 i was unable to run Barry's coilgun simulator in my laptop which has internet explorer 8 with java version 8 updated 101.
can u plz suggest me how to run the simulator
Re: help need to calculate the out put current of a capacitor
Barry, Mon Nov 21 2016, 04:59AM
Did you ever get the RLC simulation page working?
It can still run in Windows 10 but the the environment gets more difficult to set up every year.
~ Barry ~
Barry, Mon Nov 21 2016, 04:59AM
Did you ever get the RLC simulation page working?
It can still run in Windows 10 but the the environment gets more difficult to set up every year.
~ Barry ~
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