Load flow method for distribution systems

This paper gives an efficient method for solving load flow studies in a distribution system that can be used for both radial and mesh systems A radial network is obtained from a mesh network by process of loop breaking by addition of dummy buses. The injected power at loop break points are obtained and updated by iteration process by an impedance matrix. IEEE 9 bus network was used to prove the convergence of this method and verified by MATLAB programs and compared with conventional methods using ETAP.

I. Introduction

Load flow studies plays an important role in understanding a power system. It is most important for power system planning and operation. It gives the sinusoidal steady state of the entire system voltages, real and reactive power generated and absorbed and losses. Out of the four main parameters namely voltage (V), power angle (), real power (P) and reactive power (Q), two are known and two are unknown in any power system network. To calculate the unknown parameters, the load flow equations are used recursively in number of iterations. Traditionally there have been various methods such as Newton-Raphson and Gauss-Seidel to solve the load flow problem. However certain drawbacks are encountered in these methods.