By Ebru Tuncay and Can Sezer ISTANBUL, April 17 (Reuters) - A Turkish government team visited Portugal recently to meet potential investors for Ankara's plan to privatise billions of dollars worth of state-run highways and bridges, three sources familiar with the situation said. Turkish government privatisation board officials and EY, the global consultancy that was hired last year for the sale, held the meetings in recent weeks, two sources told Reuters, requesting anonymity.