Interesting.
The difference of course is that was a dead end one shot experiment. The WAG9HH is to become a production locomotive with hundreds to be built and deployed. Its precursor the WAG9Hi 7,000HP has almost a thousand of them running around the entire IR network.
Some other interesting differences I notice - I suppose the older locomotive was DC drive train. The newer locomotive is 40 tonnes lighter. It is likely that there are interesting other significant differences. And that experimental locomotive IMHO is b u t t ugly, but beauty is in the eyes of the beholder.
What is interesting is that IR is developing this 9,000HP Co-Co, which I am told is not that hard to bump upto 10,000 HP but little motivation to go there, possibly because IR is also manufacturing the Alstom Prima 12,000HP Bo-Bo+Bo-Bo. So they have three freight electrics in their stable going forward, a 6-7000 HP original WAG-9 and WAG-9Hi (Heavy IGBT), a 9,000HP WAG0HH (Heavy High HP) a 12,000HP WAG12 Prima.
In addition, IR is also developing the 12,000HP WAG11 Co-Co+Co-Co developed by conversion of two WDM2 Alco diesels into pure electric with new drive. That uses the same core AC drive but with less powerful motors, since it has 12 axles to spread the power among. Given that in another 5 years almost all of IR routes will be electrified, they are looking at ways to reuse their existing diesel frames instead of just scrapping all of them.
I think the other motivation for developing the WAG9HH drive train is to port that back into the WAP-7 to create a (currently hypothetical) WAP-9 9,000HP 160kph (100mph) passenger locomotive.
It is amazing what sorts of things one can do when one knows there will be need for thousands of units of various capabilities going forward.
