Optimal Placement of Meters in a Physical Electrical Network for Real-Time Harmonic State Estimation Assessment

Abstract

This contribution presents a methodology for optimal placement (OP) of meters in power systems, using the state-space reference frame. The goal is to minimize the state estimation error, specifically, the mean squared error (MSE), through OP of a limited number of measurement devices and keep the total observability of the system. The measurement set is applied to the time-domain state estimation based on the Kalman filter (KF) to obtain voltage and current waveforms in real time, and the harmonic content is evaluated through the application of the Fast Fourier Transform (FFT). The effectiveness of harmonic state estimation (HSE) is demonstrated in case studies considering different operating points in a test electrical network, particularly in estimating the dynamic behavior of nonlinear electrical loads. The HSE method is implemented in physical tests using Lab-Volt® equipment to monitor the system in real time using MATLAB/Simulink® software through the RL-LAB® platform; the real-time experimental tests (RTE) allow validation of the real-time digital simulation (RTS).