Harmonic Distortion State Estimation Using an Evolutionary Strategy

Abstract

Abstract-This paper presents a new methodology to estimate harmonic distortions in a power system, based on measurements of a limited number of given sites. The algorithm utilizes evolutionary strategies (ES), a development branch of evolutionary algorithms. The main advantage in using such a technique relies upon its modeling facilities as well as its potential to solve fairly complex problems. The problem-solving algorithm herein proposed makes use of data from various power-quality (PQ) meters, which can either be synchronized by high technology global positioning system devices or by using information from a fundamental frequency load flow. This second approach makes the overall PQ monitoring system much less costly. The algorithm is applied to an IEEE test network, for which sensitivity analysis is performed to determine how the parameters of the ES can be selected so that the algorithm performs in an effective way. Case studies show fairly promising results and the robustness of the proposed method.Index Terms-Evolutionary algorithms, evolutionary strategy, harmonic distortion, power quality (PQ), state estimation.

Three-Phase Harmonic Analysis Method for Unbalanced Distribution Systems

“…The voltages of the shunt equipments such as harmonic filters can also be calculated by multiplying their harmonic currents absorbed and harmonic impedance. For example, the voltage of shunt equipment at bus y can be expressed as: The bus voltages of shunt equipments can then be expressed in vector form as Equation (14). Equation (14) can be rearranged and written as Equation (15) and then Equation (16) can be derived.…”

“…Many methods have been proposed to analyze and eliminate the harmonic impact produced by nonlinear loads [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16]. Among them, harmonic analysis is one of the most powerful tools for harmonic impact analysis.…”

“…Owing to the unbalanced line sections and loads in distribution systems, a three-phase harmonic analysis method is essential to accurately analyze the harmonic impact on distribution systems [7][8][9][10][11][12]. The harmonic analysis is also the basic tool for harmonic filter design and harmonic resonance mitigation and has to be done repeatedly for each harmonic order [13][14][15][16]; therefore, the accuracy and efficiency are both important issues for a well-designed harmonic analysis method. Conventional harmonic analysis methods [7][8][9][10][11] don't consider the special topological characteristics of distribution systems such as the unbalanced loads and radial network structure; therefore, the solution accuracy cannot be further improved and computational time cannot be effectively reduced.…”

Harmonic filter design for Variable Frequency Drives in marine vessels based on a systematic power quality assessment and monitoring methodology

“…n' n = 5 , 7 , 11 , ... , 25 (15) Magnitudes of existing power system voltage harmonics, VLLn . ,}" are obtained before VFD application by power quality measurements, so total generated voltage harmonics are: The total voltage harmonic distortion (THDv%) can then be calculated at PCC and checked against requirements: …”

Power quality meters placement using seeker optimization algorithm for harmonic state estimation

“…This is commonly referred as HSE, i.e. a reverse operation of harmonic simulation which determines the response of a power system to the existing harmonic sources [3][4][5]. The quality of the HSE depends on the number of measured variables and the location of meters in the power system [6][7][8][9].…”