Development of New Admittance Matrix for Newton-Raphson Power Flow in Distribution Networks

Network modelling is a critical step in the analysis of distribution networks. It is used to relate the input currents and voltages with the output currents and voltages. This work aims to construct a new admittance matrix for distribution networks. The new admittance matrix is derived based on ABCD matrix, which presents the exact model of different types of power distribution networks considering the unbalance/balanced and single/three phase characteristics. The model takes into account shunt admittances to reflect the accurate performances of the components in the distribution networks, especially in the presence of distributed generation units. The importance of considering shunt admittance is due to the presence of capacitive charging current which can affect the node voltages. Application of the new admittance matrix of distribution networks in Newton-Raphson power flow analysis is performed. The standard IEEE 37 bus system is used to test the validity of the proposed approach. MATLAB environment is used to confirm the results. Simulation results show the accuracy of new network admittance matrix in power flow analysis.