and;
Research;
Institute;
of;
Guangzhou;
Power;
Supply;
Bureau,;
Guangzhou;
Power;
Supply;
Bureau,;
Guangzhou;
510410,;
China;
Key;
Laboratory;
of;
Power;
Transmission;
Equipment;
&;
System;
Security;
and;
New;
Technology,;
Chongqing;
University,Chongqing;
400030,;
China;