According to the police, the fire broke out due to a short circuit when power was being fed into the local grid on a trial basis.
However, a company official maintained that such minor incidents are common during the trial run.
The plant is run by Adani Green Energy (Tamilnadu) Ltd.
Police said the fire was doused and steps taken to replace the burnt panels, adding that power generation would begin shortly.
Currently, power generated from the panels is used for the plant's own consumption.