[1] Shenyang Univ Technol, Shenyang 110870, Peoples R China
[2] State Grid Jibei Elect Power Co Ltd, Qinhuangdao Elect Power Supply Co, Qinhuangdao 066000, Hebei, Peoples R China
[3] Aalborg Univ, DK-9220 Aalborg, Denmark
[4] State Grid Liaoning Elect Power Co Ltd, Fuxin Elect Power Supply Co, Fuxin 123000, Peoples R China