A wind turbine generator(WTG)with a power rating of 100 kW and a variable pitch control system was developed for isolated islands. The WTG was designed according to the international standard(IEC 61400-1)with survival wind speed of 80 m/s and built on Kume-Island, Okinawa, in 2009. The Kume-Island have abundant wind energy resources because of annual average wind speed of 6.2 m/s, furthermore there is a strong likelihood of typhoon hits once every year or more. The WTG controlled an AC-DC-AC power converter system interconnects an end of small utility grid with diesel-engine generators of 18,500 kW. In field testing, several typhoons hit the Kume-Islands, however, the WTG didn't have serious damage. The development targets which are low acoustic noise, high strength, good quality electric power etc. have been demonstrated successfully. This paper shows typical examples of field test data in summer season and winter season.