That doesn't sound good. I guess it is possible but unlikely that the power supply could take out the drive. I would think it might be the other way around. I suggest that the drive may have failed, but even that is unusual. It sounds like the new power supply is current limiting to protect itself. Reversing the DC connections is a really bad idea, that could blow the drive if it is not reverse polarity protected. To start with, I might wire the motor in series rather than parallel configuration. You will lose some torque, but the load on the drive will be reduced. With the power off, disconnect the motor from the drive, then power up the drive and see if the power supply still current limits. If it does, the drive may have failed.