A new integrated protection scheme based on transient polarity comparison principle is proposed for the distribution system with multi distributed generators integrated. The transient polarity comparison consists in extracting the information in a certain frequency band of fault transient high frequency signals with wavelet transform as the basis of fault judgement to quickly and accurately judge the position of fault. The transient polarity comparison protection is applied to the integrated protection

in which the integrated protection unit is built based on the busbar. The local fault information and the fault information of adjacent protective units is used to compare the polarity of the lines out of the busbar to judge the busbar fault as well as the polarity at both ends of the line. Meanwhile the integrated network protection unit extracts multi-point information and makes a comprehensive comparison between the transient signal polarities of the whole area to realize fault isolation

rapid positioning and to provide backup protection for local protection. Finally

MATLAB is used to simulate the analysis

with the correctness and feasibility of the protection scheme verified by simulation results. This work is supported by National Natural Science Foundation of China (No. 51422703).