Inrush current in smps and it's inductors?

[markusA]

I've been running some LTspice sims for a 12V/150V smps and there is one issue that's really bugging me.
The current rating on inductor!

I have a 100uF cap in the output filter and when the psu is switched on it draws a lot of current. Even when a current limiter is applied on the 12V supply the inrush current through the inductor will spike.
There's a 130us spike supplied by the input caps.
I've tried to keep everything rated for 3.5A but this single spike will reach almost 5.5A.

How big a spike can a inductor handle?
Almost all the inductors I find are rated for Idc or Irms but I can's seem to find any solid info on how big a current peak they can handle?

If I open up the current limiter the spike will have a longer duration and a higher peak.
It would really suck to build the psu just to fry the inductor on the first trial run...
Using a oversized piece will almost double the cost which is a bad thing when trying to keep it cheap and simple.

So, is there a way to estimate how big a spike an inductor can handle and for how long?
We're only talking of ONE peak surge at start-up.

[sawreyrw]

I don't know the topology of your supply, but a current mode controller has cycle by cycle current limiting and should eliminate this problem.

As for the inductor current rating, there are 2 general comments. First, if the inductor saturates, it will not be damaged so long as the current remains below the 'fusing' current; however, other bad things could happen. Second, the inductor shouild have some kind off a spec related to saturation. A good spec sheet would show inductance vs. current or spec inductance roll off some other way.

[markusA]

To make things a little easier, here's a screen grab from LTspice.
I've been looking at spec sheets and it's very confusing? Each manufacturer seem to have their own way of defining the specs?
No graphs, only numbers which you can't compare to anyone else.

Now, as everyone can see the current isn't centered at ground but swinging at half peak with minimum @ slightly below zero. (I think it's supposed to be zero but there might be a light mismatch componentwise.)

The target is finding a 220uH inductor that is comfortable with this current.

[johansen]

i think that's a simulation problem, because a half sine wave 130us long with a 5.5 amp peak current will not charge a 100 uf cap to 12v. it will only charge to about 5 volts or so.

We need your schematic to tell you anything more.

[markusA]

Ok, here's the schematic. It's not an original of my own but something I found on-line. I've been trying to figure out how everything works and how to modefy it for my own needs.
(see Steve's Tube Pages for the original)

[sawreyrw]

This is a voltage mode (not current mode) boost supply. If the inductor saturates, the MOSFET will likely be damaged.