Bridge Rectifier Dimensioning for SMPS

Question

I want to know how to dimension a bridge rectifier.

As an example,in a SMPS, the bridge rectifier has repetitive peak current, up to 10A at rate of 100kHz, but in a small period of time, like a small duty cycle. But the average current is 1A. How do I choose the component (bridge)? Based on its mean current value, on its peak current, or calculating the I²t to mach the datasheet specifications?

I read something about dimensioning it using I²t specification from datasheet, but on GBJ3510 (for example) there's a disclaimer about this value being for non repetitive peaks.

The situation expressed above and on the previous edits were only examples to serve as a tool for the main question of how to dimension the bridge based on current aspects.

Answer 1

Your PFC-less design is fundamentally flawed. That 14.4V 200A output alone can provide almost 3kW. At these power levels, a PFC is actually mandatory.

If you plug this thing in as you've drawn it in your schematic, you're going to detonate the bridge rectifier and trip all breakers within line of sight of that contraption. The capacitors act as a dead short as they get charged up by mains.

Additionally, even if you managed to somehow get this circuit to survive the inrush current, it'll consume mains power in horrible spikes approaching 200A of instantaneous current (I simulated it). That's again pretty much guaranteed to (magnetically) trip most breakers rated for 32A or less. In other words: Your circuit is drawing power in spikes of almost 40kW, 120 times per second. This is really bad.

If you still want to spec a proper rectifier, you'll need one that can handle 200A at 10% duty cycle, as can be seen in the simulation.

Please, though, build a PFC, even if just a passive one.

An active PFC (power factor correction) circuit usually consists of a boost converter that tries to match its input current draw to the sinusoidal waveform of the incoming mains voltage. This makes it essentially present itself as a resistive load to mains. The output of such a PFC provides a more-or-less smoothed ~400V DC, which is exactly what you need to power your subsequent isolated converter stage. If you don't want to build an active PFC, a passive PFC consisting of suitable inductor in series with the line input might help a bit.