Patent 9982555 was granted and assigned to Hitachi, Ltd. on May, 2018 by the United States Patent and Trademark Office.
A gas turbine power generation system has a dual-shaft gas turbine, an electric generator mechanically connected to a low pressure turbine of the dual-shaft gas turbine and electrically connected to an electric power system, a rotary electric machine mechanically connected to a high pressure turbine through a compressor of the dual-shaft gas turbine and electrically connected to the electric power system, and an electric power output from the electric generator side to the electric power system is adjusted by operation of the rotary electric machine as a motor or as a generator.