Abstract: In view of the limitation of subjective weight and objective weight, an optimization model of comprehensive index weight based on least square method （LSM） was put forward to evaluate the power quality of wind farms. The overall evaluation model based on LSM was established to reduce the estimated deviation. Then, the organic unity of AHP （analytic hierarchy process） in both subjective and objective assignment methods was achieved by constructing a Lagrangian function to solve the conditional extremum. Through the simulation of Chang Maxi wind farm in Gansu province, it is demonstrated that the power quality assessment results of wind farm bus, based on the model of comprehensive index weight optimization of LSM, are correct and reasonable, which can prove the validity of the model.

Key words: power quality assessment, index weight, least square method, wind farm, analytic hierarchy process