Estimating Power Losses due to Harmonics in Power Distribution System Components

This paper addresses the urgent need for accurate estimation of power losses caused by harmonics in various components of power distribution systems (PDS). Current methodologies for evaluating such losses in electrical distribution grids (EDG) are underdeveloped, highlighting the necessity for more refined analytical approaches. To address this gap, a mathematical model was developed to quantify harmonic-induced losses across key PDS components, with a focus on dry-type distribution transformers (DDTs). Expected accuracy range for estimating methodology was Class 2 accuracy range according to AACE1. Mathematical model was validated by using pre-existent tests performed on a 250 kVA DDT. Power losses of DDTs are especially significant because these components play a critical role in power system efficiency and revenue generation. In the commercial and industrial sectors, approximately 50% of electricity passes2 through DDTs, of which 40% of DDT efficiency is affected by harmonic losses [2]3. As electrification and electric vehicle adoption grow, these losses are expected to increase. By identifying components most affected by harmonics, the model enables targeted mitigation strategies, potentially saving 600 GWh annually and reducing power losses by 70 MW4 [3]. The paper concludes with a guide to the use of the proposed mathematical model for the estimation of Harmonic Power Losses and Applicable PDS Components (Appendix C). Proposed mathematical model offers consultants, engineers and end-users a practical tool to improve transformer sizing, implement energy-saving measures, and enhance the efficiency and reliability of PDS. The outcomes support stakeholders, including utilities and customers, by reducing operational costs, extending equipment lifespans, and improving energy efficiency. The findings are a useful tool for government organizations and utilities in refining their energy efficiency programs and standards.