A Comparative Analysis between Methodologies for Responsibility Assignment on Harmonic Distortions

Abstract

A current challenge which emanates from the Power Quality area is the search for a reliable means for sharing the responsibility assignment on harmonic distortions between the parties involved. In fact, to determine the THD (Total Harmonic Distortion) levels for the points of coupling between the suppliers and consumers, the identification of the individual contributions of the parties is presented as information relevant to any mitigating measures. In this context, although in literature there have been some highlighted methodologies, which aim at characterizing portions of responsibility between the agents, due to the subjects concerning the procedures, there are still frequent questionnaires concerning the conclusive contribution from the parties. Thus, this article summarizes the main procedures found in literature and through the implementation of a hypothetical test system that operates under three distinct conditions, a set of performance computational studies are carried out. The studies yield results that are utilized as a comparative and critical base of the methodologies being directed towards the motives described herein, while highlighting their potential along with limitations.

Dominant impedance method to assign harmonic voltage contributions at a point of common coupling

“…6,7 Other methods, as the conforming and non-conforming current 8,9 procedure and a proposal based on the capture and treatment of voltage and current waveforms at the interest point, 10 although very interesting and practical at first sight, showed inconsistencies in their development when subjected to performance evaluations. 11 Furthermore, several studies employ resources such as neural networks, state estimation, linear regression, and statistics, among others. [12][13][14][15] One can state that in this field many publications demonstrate the use of mathematical and computational resources for identifying the main points of distortion causation in a system.…”

Assignment of harmonic voltage contributions using the harmonic current injection method

“…An analysis of the literature revealed that efforts have been made in different lines of research associated with this subject. In fact, there are proposals 8‐13 with strong inconsistencies in their physical principles, as evidenced in different performance evaluation studies 14‐16 . In addition, many studies use mathematical and computer resources such as neural networks, state estimation and among others 17,18 .…”

Capacitor switching methodology for responsibility sharing of harmonic voltage distortions

“…Another procedure, known as the conforming and nonconforming current method, considers in its development simplified hypotheses that significantly affect the suitability of the proposal in physical terms. Likewise, performance studies verified the weaknesses found in the method …”

“…Likewise, performance studies verified the weaknesses found in the method. 18 Within this context, the superposition method 13,14 certainly presents relevant importance. 18,19 As the name suggests, it is based on the classic principle of the superposition of circuits and as such provides unquestionably consistent results.…”

“…18 Within this context, the superposition method 13,14 certainly presents relevant importance. 18,19 As the name suggests, it is based on the classic principle of the superposition of circuits and as such provides unquestionably consistent results. Nevertheless, its application in the field is very difficult due to the need to know the value of the harmonic impedances of the parties involved.…”