Hi!
i'm building a 28V/2.5A DC power supply and i'm using a 24V 100VA transformer. I have used a simple capacitor filer after the full wave bridge rectifier with 4x3300uF capacitor bank and i was aiming for about 2V pp ripple. But at full load the voltage after the capacitor filter was dropping to about 29.7 volts while the transformer output voltage was normal  about 24.4V AC.
I assumed that there was a big power loss in the bridge rectifier (KBPC2504) because it was heating up anyway (finger test  about 70C), and i did some simulations. I notice big current spikes at the input of the bridge rectifier (about 28A) and that will explain where the missing voltage drop was going (yes i know simulations can be a bit wrong but i pulled out the rectifier and passed 2.5A of dc current thru 2 of its diodes for some time and it didn't get hot at all, not even warm). Then i did some internet researching and it turned out these current spikes are absolutely with the simple capacitor filter.
So my question is the simplest solution just to mount the rectifier to a heat sink and call it a day? And i know that the voltage after the rectifier is 1.62 volts lower than the input voltage but i am getting quite a bit more average voltage drop. I was reading about a inductor in series before the capacitors and its purpose is to reduce exactly these current spikes but i'm not sure how to choose a value and what are (and are there any) downsides of using an inductor (effectively a LC filer).
This is the current circuit:
i'm building a 28V/2.5A DC power supply and i'm using a 24V 100VA transformer. I have used a simple capacitor filer after the full wave bridge rectifier with 4x3300uF capacitor bank and i was aiming for about 2V pp ripple. But at full load the voltage after the capacitor filter was dropping to about 29.7 volts while the transformer output voltage was normal  about 24.4V AC.
I assumed that there was a big power loss in the bridge rectifier (KBPC2504) because it was heating up anyway (finger test  about 70C), and i did some simulations. I notice big current spikes at the input of the bridge rectifier (about 28A) and that will explain where the missing voltage drop was going (yes i know simulations can be a bit wrong but i pulled out the rectifier and passed 2.5A of dc current thru 2 of its diodes for some time and it didn't get hot at all, not even warm). Then i did some internet researching and it turned out these current spikes are absolutely with the simple capacitor filter.
So my question is the simplest solution just to mount the rectifier to a heat sink and call it a day? And i know that the voltage after the rectifier is 1.62 volts lower than the input voltage but i am getting quite a bit more average voltage drop. I was reading about a inductor in series before the capacitors and its purpose is to reduce exactly these current spikes but i'm not sure how to choose a value and what are (and are there any) downsides of using an inductor (effectively a LC filer).
This is the current circuit:
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