Fuzzy time domain and Z-transform for modeling of harmonic electric loads

This paper demonstrates the application of fuzzy systems and Z-transform fo r electric load modeling in the presence and/or absence of harmonics. The p roblem is formulated as a linear optimization problem, where the objective is to minimize the spread of the model parameters. A triangular membership function is chosen for each load parameter. Having identified the fuzzy loa d parameters, the fuzzy admittance of the load is formulated in the frequen cy domain. The proposed algorithm is tested using simulated and actual reco rded data for nonlinear loads having different characteristics. The results obtained are reported in the paper.