GENEVA, June 1 -- GUANGDONG POWER GRID CO., LTD (No. 757 Dongfeng East Road, Yuexiu DistrictGuangzhou, Guangdong 510600), 广东电网有限责任公司 (中国广东省广州市越秀区东风东路757号), ZHONGSHAN POWER SUPPLY BUREAU OF GUANGDONG POWER GRID CO., LTD (No. 68 Boai 6th Road, East DistrictZhongshan, Guangdong 528400), 广东电网有限责任公司中山供电局 (中国广东省中山市东区博爱六路68号) filed a patent application (PCT/CN202...