Abstract:In order to solve the problem that the traditional least square method is not able to deal with the coarse difference in the measured data of harmonic state estimation, a method based on IGG method is proposed. Resistance Estimationis one of the commonly used statistical inside for gross error is contained in the data processing method, and poor resistance to the least square method is combining Estimation and least squares method a new method of Estimation. This method can reduce the weight of the measured data, improve the weight of the measured data, and thus resist the bad influence of the coarse difference on the estimation result. At the same time, most current distribution network using a simplified model of single-phase harmonic state estimation model, does not take into account the characteristics of the three-phase unbalanced distribution network, this paper established the mathematical model of three-phase power distribution network, and USES the IEEE33 node system analysis, simulation mixed with gross error in the measured data respectively using poor resistance to the least square method and the traditional least squares solution and the error estimation results of numerical example results show that the resistance is poor least-square method has stronger ability to resist bad and estimation precision is superior to the traditional least square method