Parameter Identification and Quick Correction Method With Considering Leverage Measurement

Under the existence of bad leverage point the defects in existing parameter estimation methods, such as low accuracy and high computation complexity, will appear. A new Lagrange multiplier based method to identify power grid parameters and rapidly correct them was proposed. Firstly, an exponential objective function based robust state estimation model, which could automatically revise the weights of the measured errors according to the sizes of them, was established to reduce the affects of large portion of bad data, especially the bad leverage point, on parameter identification accuracy. Secondly, based on Lagrange multiplier method the suspicious parameters were be determined, and then according to the multiplier values of suspicious parameters at multi-sections the average multiplier values utilized for error revision were calculated to implement fast revision of parameter errors, meanwhile the calculation amount was decreased. Taking 3-bus simple network and IEEE 39-bus system for example, under the existence of bad leverage point, both parameter estimation accuracy and computation time by the proposed method and traditional method are analyzed, thus the effectiveness and correctness of the proposed method are verified.