A STUDY OF AN URBAN DOMESTIC COMPOSITE LOAD MODEL SUITABLE FOR SOLAR PV AND GRID HYBRID SYSTEM

Abstract

In every power supply system, the load is a major component to the system voltage stability. For this reason, load modeling is done to predict the  behavior of the load. The load behavior in a power system directly affects the voltage profile of the system. In most generation systems in a country, the urban domestic load consumes up to 30% of the total generated power. It is with this fact in mind that this paper carried out an urban domestic load modeling to study the effects of disturbances and perturbations caused by the load to a power generation system. In the study, a solar PV and grid hybrid system is used. An equivalent circuit of an induction motor is used as a dynamic load together with the static domestic load to form the load model. The study uses both quantitative and qualitative analysis methods and also explores the use of trajectory sensitivity concepts. Using load analysis software; Excel and MATLAB the load was modeled. The domestic load used in the study is drawn from a study case suburb; Embakasi Nyayo Estate. Preliminary results obtained indicate accurate predictions for the hybrid solar PV and grid system. The investigations further  indicate that load voltage dynamics can significantly influence the damping of modal oscillations. Further, as the system becomes more stressed, sensitivity to parameter variations increase significantly and this can be used to predict marginal stable behavior.