The generator on my TO-30 is charging at 15 amps where previously it was charging at two. Is that normal or indicating a problem?
It is possible you have a shorted cell in your battery which is making the voltage regulator think the battery is down, and kicking the generator into the high charge rate.
It is also possible the wire going to field terminal is shorted to ground. This will kick the generator into the high charge rate. Carefully inspect the wiring going to the generator, and voltage regulator.
It is also possible your ammeter, voltage regular, or generator is bad.