Data-Driven ZIP Load Parameter Tracking with Variable Elimination Using Synchrophasor Data

Accuracy of the load behavior model is essential for power system operation and analysis. ZIP mathematical model is commonly used to represent the power and voltage dependency. To correctly estimate ZIP parameters and derivatives, sufficient changes in voltage synchrophasor measurements are required to avoid ill-conditioning. Estimating non-existing load parameters or derivatives in a given measurement window data will lead to inaccuracy, and these variables need to be eliminated for better estimation results. This paper presents load parameter estimation using least squares and step-wise regression with variable elimination. A confidence factor is generated as a measure of accuracy for both estimation methods. ZIP estimation for various load compositions for IEEE 14 bus Test System is presented to demonstrate the proposed techniques' effectiveness.