Delhi Metro Rail Corporation (DMRC) authorities claimed that the problem lasted for around 30 minutes, between 2 PM and 2.30 PM, and that it was sorted quickly and normal services restored.
However, passengers complained that trains were stuck at many stations along the corridor for longer durations.
"Trains were running slow between 2 PM and 2.30 PM due to power fluctuation. Services were not suspended," a metro official said.
The Union Urban Development Ministry has asked the DMRC to submit a report on snags frequently hitting the corridor with an analysis of reasons and measures to be taken to address the same.
Last month, DMRC had apologised to the people after a major glitch led to trains losing contact with its Operational Control Centre for two successive days, triggering long delays and outrage.