Point estimate method of Load Flow for distribution network with photovoltaic generators

The modernization of power system has increased the number of distributed generation system (DG) connected to distribution network. Most of these DGs are non-conventional, taking environmental conditions into concern. The energy generations of such DGs (Photovoltaic (PV) or Wind energy generators) are uncertain as their prime sources of generation are also uncertain or intermittent. An appropriate analysis must be carried out to check the distribution network operating conditions. In such scenarios Probabilistic Load Flow (PLF) calculations are used to obtain the accurate as well as possible solutions. This paper deals with the solution of the load flow problems in distribution networks with Photovoltaic DG unit. Suitable models for the prediction of active power produced by PV DG units and the power absorbed by the loads are used to represent the uncertainty of solar energy available and load variation. The proposed model is incorporated in a radial network and the PLF using; Two point estimate (2PEM) as well as Three point estimate (3PEM) schemes of point estimate are carried out and their performance is compared with the Monte-Carlo simulation.