Voltage controlled PSU for simulating noise in power systems?

[rx8pilot]

I hope the title is not too strange. The hope is to find a power supply that I can inject various noise and spikes into a load based on a waveform from an ARB. The end use of this is to simulate various power rail problems and test circuits that are intended to deal with them.

In some cases  it would be used to add low-voltage ripple on top of 10-20VDC / 10-15 Amps. In some cases it would be used to simulate inductive spikes as high as 100Vor so. It's not unlike an audio amplifier, but hopefully higher bandwidth and some programmable limits. I have not thought through the high-end of the bandwidth yet, but I suspect that it would be hundreds of Khz or so.

Google searches did not turn up anything, but the quality of my search input is probably not so good either. Is this an off-the-shelf device? .

Thank you in advance to anyone willing to help. If you have some other method of simulating bad power, that would be just as helpful.

[Dave]

What you're looking for is a line injector.
Basically it's a transformer in series with the power supply and you then feed the AC signal into the other coil. That way you get an AC signal superimposed onto the DC from the power supply.