kanmaedexandzelbladex
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Hi,
I would like to ask about shutting down boost converters. Let's say I have a boost converter such as in this figure **broken link removed** . Let's say that my inductor current is at 10A and my input voltage is let's say around 12V and the converter is at steady-state. If I suddenly remove the input, then the inductor current cannot get the current anywhere and since di/dt = instantaneous (current is being forced to 0A immediately), then voltage across it is forced to be really high. This would be problematic? What could happen if I try to do this in real life?
Next question is let's say I want to remove this. I plan on putting a capacitor in the input (parallel to the input voltage source)which most DC-DC converter designs I have seen has this and they label it sometimes as Bulk capacitor. First I thought it acts as a filter only but then I thought that if the input is suddenly removed, the inductor current could get current from that capacitor and slowly drain its voltage. Is this correct? Is this a good solution?
Now the next question is how should I size this input capacitor? From theory, if inductor current is 10A, then at the removal of the input, 10A = C dV/dt. So should the capacitor be sized only with the wanted dV/dt (turn-off time)? Are there other considerations for this capacitor? I'm not too sure if a capacitor can handle 10A discharge current will it explode?
Thanks
I would like to ask about shutting down boost converters. Let's say I have a boost converter such as in this figure **broken link removed** . Let's say that my inductor current is at 10A and my input voltage is let's say around 12V and the converter is at steady-state. If I suddenly remove the input, then the inductor current cannot get the current anywhere and since di/dt = instantaneous (current is being forced to 0A immediately), then voltage across it is forced to be really high. This would be problematic? What could happen if I try to do this in real life?
Next question is let's say I want to remove this. I plan on putting a capacitor in the input (parallel to the input voltage source)which most DC-DC converter designs I have seen has this and they label it sometimes as Bulk capacitor. First I thought it acts as a filter only but then I thought that if the input is suddenly removed, the inductor current could get current from that capacitor and slowly drain its voltage. Is this correct? Is this a good solution?
Now the next question is how should I size this input capacitor? From theory, if inductor current is 10A, then at the removal of the input, 10A = C dV/dt. So should the capacitor be sized only with the wanted dV/dt (turn-off time)? Are there other considerations for this capacitor? I'm not too sure if a capacitor can handle 10A discharge current will it explode?
Thanks