Probabilistic power flow with nonconforming electric loads

A comprehensive model for probabilistic power flow is proposed for the purpose of estimating the statistics of bus voltage magnitudes and circuit currents, given the statistics of the loads. The proposed method is based on the quadratized power flow model and a nonconforming electric load model. The statistics of the electric load are accurately represented with the statistics of a few independent random variables and the statistics of bus voltage magnitudes and circuit current flows are computed from the linearized model of bus voltage and circuit current flow with respect to these independent load random variables. The method is validated via Monte Carlo simulations in which the problem is fully solved for each random sample, thus incorporating nonlinearities resulting from the AC power flow equations. Both the linearization solution and the Monte Carlo approach are based on the single phase quadratic power flow (SPQPF) model of the power system. The proposed method has been implemented and applied to the IEEE reliability test system (RTS). The results are presented in the paper.