GENEVA, April 4 -- ELECTRIC POWER RESEARCH INSTITUTE, CHINA SOUTHERN POWER GRID (No. 11 Kexiang Road, Science ParkHuangpu DistrictGuangzhou, Guangdong 510663), 南方电网科学研究院有限责任公司 (中国广东省广州市黄埔区科学城科翔路11号), GUIZHOU POWER GRID CO., LTD. (No. 17 Binhe Road, Nanming DistrictGuiyang, Guizhou 550002), 贵州电网有限责任公司 (中国贵州省贵阳市南明区滨河路17号) filed a patent applica...