An improved load flow technique based on load current injection for modern distribution system

Abstract

This paper presents load current injection based improved load flow (LF) technique for modern distribution system. The proposed LF technique is derived by promulgating the concept of conventional backward forward sweep technique. This proposed technique uses a single load current to bus voltage (LCBV) matrix to perform both the backward and the forward sweeps of power flow calculation in a single step. Utilizing the concept LCBV, the bus voltages can be determined, directly, from the load current injections. Due to the distinctive solution technique of the proposed approach, the time-consuming lower–upper factorization and forward–backward substitution or any derivative operation required in the traditional LF technique are no longer necessary. These unique features make the proposed technique faster in operation. The proposed approach is flexible enough to accommodate any sort of change in network structure due to reconfiguration. Along with the modeling of various equipments of distribution system (viz. distribution transformer, voltage regulator, voltage dependent loads, distributed generations, etc.), special treatments for weakly meshed system are also presented in this work. It is experimented on several test systems of varying complexities (viz. 28-, 69- and 30-bus balanced radial distribution system (RDS), 10-bus and IEEE 34-bus unbalanced RDS and 33- and 69-bus weakly meshed system) and the obtained results demonstrate the effectiveness of the proposed approach while comparing to the existing methodologies. Furthermore, it is revealed that the proposed algorithm is, computationally, faster, robust and more suitable for modern distribution network than the contemporary techniques available in the state-of-the-art literature.