A Novel Method for Load Allocation and Loss Calculation in Primary Distribution Systems Using Limited Load Data

Many distribution utilities in developing countries face challenges such as inadequate load meters, poor data management, and high data collection costs, resulting in a lack of crucial technical data for accurate load flow analysis. Existing methods, such as the Linear Factor approach, fail to capture the unique characteristics of different distribution systems, leading to inaccurate loss estimations. This paper presents a novel approach to obtain load data for the balanced three-phase load flow method tailored for scenarios with limited data availability. The proposed approach calculates the loadings of all the Utility Distribution Transformers (UDTs) for each feeder using the load characteristics of the feeder's sending end and private customers. Individual loadings are then allocated based on one-time measured peak currents. The load flow analysis is conducted using a backward and forward sweep method to determine losses in the primary distribution system. A load scaling technique is subsequently employed to ensure the energy recorded at the feeder origin matches the sum of the total allocated load and High Voltage (HV) feeder line loss. The proposed method incorporates daily and monthly load variations, enhancing its robustness. This methodology has been applied to the Kavre Substation in Nepal to calculate distribution loss in its 11kV system, demonstrating its applicability under constrained load data conditions.