Liu, Ju; Wen, Jinyu; Yao, Wei; Long, Yao: 'Solution to short-term frequency response of wind farms by using energy storage systems', IET Renewable Power Generation, 2016, 10, (5), p. 669-678, DOI: 10.1049/iet-rpg.2015.0164 IET Digital Library, https://digital-library.theiet.org/;jsessionid=2dhd9il12a6gj.x-iet-live-01content/journals/10.1049/iet-rpg.2015.0164