In order to narrow the range of fault identification and improve the speed and reliability of protection,a novelprotection algorithm is proposed in this paper by studying the propagation characteristics of fault traveling wave signalsin power gird through PSCAD/EMTDC simulation and Matlab calculation. With the proposed method,the initial travel-ing wave reactive power is defined,and the distribution characteristics of the reactive power of wide-area initial travel-ing wave are analyzed when fault occurs in ...