I have a 48V 50A SMPS driving a fairly erratic load. The load varies wildly between 1 and 10A and can suddenly drop from full load to low load. I don't have an oscilloscope at hand, so these are estimates.

The load is very tolerant and won't care much about voltage variations in either direction. The problem is that the over-voltage protection on the power supply is fairly aggressively tuned at around 54…56V. It trips pretty often. I believe this is because the output regulation can't quite keep up with the sudden drops in the load.

What can I do to remedy this issue? I have considered the following:

* Add a resistive dummy load in parallel to help the regulation in case it struggles at low loads. How should I size it? 10A? 480W is a heck of a lot of power to dissipate in a resistor.
* Add a capacitor across the power supply output. I have no idea what size it should be to have an effect, but my guess is *huge*.
* Add a TVS diode across the power supply output. This was suggested [here](http://electronics.stackexchange.com/questions/6484/how-do-i-safely-drive-a-500w-inductive-load-with-a-computer-power-supply-and-sup/6560#6560) and indeed it seems ideal for filtering inductive spikes. But I'm not sure how well it plays in this case. Conveniently, there is a 51V part available though.

Is my diagnosis correct? What would you suggest to solve the problem?