Tug operator reported tug lost power and coasted resulted in possible nosewheel over steer and momentary loss of aircraft control.

Narrative

Pushing an Embraer 175 from the gate. The flight deck advised me to push to the top of the alleyway. I have pushed off of this gate before numerous times so I was comfortable with these instructions and proceeded with the push. This is a gate involves spinning the aircraft in the alley. While during my turn the pushback lost power and cut off. I advised the flight deck of the issue told them to set the brakes so I can get the pushback cut back on. After I restarted the pushback I put it into gear and it cut off again. I made the decision to disconnect from the aircraft and swap out pushbacks. I notified the flight deck of this and they were okay with it. After one of my agents was able to disconnect me from the towbar another Crew Chief drove up to the aircraft and advised me to stop all movement as he was concerned of a possible oversteer. I realized what happened when I felt the pushback lose power and began to coast while turning. Cause: Unsure what caused the pushback failure.A supervisor was notified and we requested for maintenance to come out to inspect the nose gear for any damage. After maintenance arrived they inspected the nose gear and manually rotated it to ensure nothing was damaged. The flight deck also advised me during the waiting period for maintenance to arrive that they had no indications on their end that an oversteer occurred. Suggestions: Refresher push training on gates that involve 'spin' pushes.