Technical loss estimation approach in power distribution systems using load model in frequency domain

Abstract

Electricity losses have been a focus of attention for Distribution System Operators (DSOs) and regulatory bodies. To define non-technical loss reduction policies is necessary to determine their amount. The strategy adopted is to calculate the technical losses to obtain the non-technical losses through the total losses difference. This paper presents an approach to estimate electric technical losses in distribution systems, showing that the load model in the frequency domain calculation is robust. Our analyses examine a model for calculating the loss coefficient in distribution systems due to dynamic energy consumption characteristics. We decomposed the load profile by Discrete Fourier Transform (DFT) and applied it to a model adapted to compute the losses spectral analysis, using the Parseval Identity. This paper examines how to estimate the coefficient up to the Nyquist Limit, considering the losses contributions to high frequencies. We evaluate this impact using a practical calculation in the load frequency domain. In this context, it would be interesting to reduce the computational cost and increase the accuracy estimate. Load flow simulations show that the model in the frequency domain presents an error of 0.1514% when compared with the model in the time domain. We obtained an error of 1.8718% using a correlation model between the loss simulations with the low-frequency components and the resolution limit. The model in the frequency domain has greater predictability, considering the load harmonic components' exponential decay characteristic. The intended purpose of this paper is defining regulatory losses in distribution systems.