For quantifying harmonic emission level

and evaluating overall the harmonic level of the user

in this paper

a new evaluation method for the user harmonic based on rank sum ratio comprehensive evalu-ation method is proposed. In this method

the uncertain user harmonic injection level is defined by the anal-ysis of time-varying characteristics of massive power quality monitoring data. Firstly

the principal compo-nent analysis is used to extract the original data in the frequency domain and the cluster analysis is used todivide the harmonic typical model in the time domain based on the main feature. Then the statistical modelof typical operating modes for harmonic pollution of users is established and the model parameters are iden-tified by the rank sum ratio comprehensive evaluation method. After that

the typical operation modal pa-rameter is identified by the use of rank sum ratio comprehensive evaluation method. A kind of new hazardevaluation index is proposed and the hazard grade evaluation is performed by the multiple days of hazardpollution degree of the user. Finally

the feasibility and effectiveness of the method is analyzed and verifiedby the algorithm simulation and calculation analysis and the grade criterion of user harmonics is quantita-tively determined.