In its Global Wind Market Update 2017 report, to be released next month, FTI found Vestas kept the number one status it reclaimed in 2016.
FTI said the Danish manufacturer had a "wide geographic diversification strategy and strong performance in the US market".
The rankings are the first since the merger between Gamesa and Siemens. As a result, the new firm moved up to second from fourth and sixth position respectively last year.
FTI said SGRE's strong position in India and in offshore helped bolster its ranking.
Chinese giant Goldwind remained in third place after being the world's leader in 2015. Goldwind remains reliant on domestic orders, and increased its market share last year.
GE was the biggest loser of the SGRE merger, moving down to fourth place, from second a year ago. However, FTI said the fall was more to do with Vestas taking the lead in the US.
According to FTI, both Vestas and GE share almost 90% of the market for projects currently under construction or in advanced development in the US.
Enercon remained the 'best of the rest' in fifth place, "taking advantage of strong domestic market growth in Germany", FTI said.
|Manufacturer||2017 Rank||2016 Rank|
|SGRE||2nd||Gamesa 4th, Siemens 6th|
"Our preliminary findings show that the top five turbine OEMs accounted for 62% of the new installations in 2017, almost 10% greater than the previous year," said FTI senior director Feng Zhao.
"The uplift is a clear indication that the recent M&A activity has helped western turbine suppliers enhance their strategic positioning and consolidate their market share.
"The further drop in the Chinese market is in general bad news for Chinese turbine vendors, as they primarily rely on their home market to secure a position in the top ten turbine supplier ranking," Zhao added.