Recently-ish Germany is also aided by the fact that the rest of the eurozone isn't doing so well economically keeping the euro lower in value than a German currency would be.
The ECB is currently making cheap money available. That's exactly what they're supposed to do and the only thing they can do, to reach their primary objective.
This happens to help Germany economically but I don't see what else the ECB could possibly do that wouldn't help Germany economically.
Also the German Bundesbank - famously paranoid about hyperinflation that definitely occurs any day now and starts the apocalypse - is strongly against the current ECB policy. So clearly the Bundesbank isn't controlling the ECB, not as much as they want to anyway.
In any case focussing on monetary policy alone and maintaining a inflation of 2% can cause issues economically but is nevertheless agreed upon to be good policy. That's why the ECB is independent, to prevent people from influencing or controlling it at times like these. It's operating exactly as designed.
Unless you're entertaining conspiracy theories, I don't see how one could argue that the ECB is controlled by Germany to somehow screw everyone else over for Germany's benefit.
Disclaimer: I'm German.
It's mostly that the government and even unions are comfortable doing things that help companies compete internationally, even if that means that wages might not rise as much for example.