Fire crews attend incident near Hunterston nuclear power station
Fire crews were called to a substation near Hunterston nuclear power station after an electrical failure.
ScottishPower said a component had failed in the Western Link plant during a commissioning test.
Emergency services attended as a "matter of routine" but were not needed, the company added.
The converter station is used to change electricity from subsea and underground cables for use in the existing electricity transmission system.
The Western Link is a joint project between National Grid and ScottishPower Transmission, which aims to bring renewable energy from Scotland to homes and businesses in Wales and England.
A spokesman for ScottishPower said: "During a commissioning test at the Western Link site today, there was a failure of a component in a substation.
"Emergency services attended as a matter of routine but were not required.
"There were no injuries, no disruption to the electricity network and no risk to the nuclear power station. SP Energy Networks, National Grid and contractors are investigating the incident."