Paper Title
Assessment of Bus Voltage Variations and Line Losses for a Microgrid Radial Feeder: A Comparison of Load Flow Algorithms

Abstract
Rural microgrids deliver power usually with radial distribution feeders. Two issues of importance to the operations engineer are to minimise the loss occurring in the feeder and voltage regulation, particularly at the extreme end of the feeder. These are evaluated using load flow analysis for a given load demand at each of the concerned buses. The load flow analysis used in the case of distributed network analysis is different from the conventionally used techniques in transmission line load flow. In this paper, a study has been made to examine the most suitable load flow algorithm for a radial microgrid feeder. The analysis is applied to a 9-bus IEEE radial feeder. Three algorithms have been tried, namely, “Forward and backward sweep methods”, Direct Approach Based Load Flow Analysis and the Gauss Implicit Z - Matrix method. Different performance parameters have been considered for the evaluation. The object is to examine which algorithm will yield the best overall result. Five evaluating parameters have been chosen, namely, S.D of voltage variation at buses, total losses in the feeder, voltage regulation at the most extreme bus, the no. of iterations needed for convergence and time of execution The results show that the all the algorithms show comparable performance and any one of these can be used in relation to accuracy. However, the forward and backward sweep involves the simplest algorithm and may be preferred in relation to other algorithms due to this feature. Keywords - Microgrid, Radial Feeder Power Analysis, Distribution Network, Distribution Load Flow Algorithms.