A measuring system model considering harmonics is developed with its effect on state estimation of the active distribution network analyzed. To begin with

the current injection model of harmonics in the distribution network is described. The MATLAB/Simulink based procedure for simulating harmonic sources is also explained. Secondly

the models of voltage and current measurement channel are proposed

respectively. The frequency characteristics of their channel cables are accounted for in detail. The whole measuring system is built with the measuring errors analyzed according to the currently available working principle of the electronic energy meter. To demonstrate the effect on measurement and state estimation by the measuring system

various numerical tests on a modified IEEE 13-bus test feeder are made by simulation that considers different scenarios including different lengths of the channel cable and different compositions of nonlinear load. This work is supported by National Key Technologies R&D Program (No. 2013BAA01B01).