scholarly journals Harmonics Mitigation Based on the Minimization of Non-Linearity Current in a Power System

Designs ◽  
2019 ◽  
Vol 3 (2) ◽  
pp. 29 ◽  
Author(s):  
Mohammed S. Almutairi ◽  
Sillas Hadjiloucas

Harmonic issues in power systems are becoming an important topic for industrial customers and power suppliers alike due to their adverse effects in both consumer appliances as well as for utility suppliers. Consumers should seek to reduce harmonic pollution, regardless of voltage or current distortion already present in the network. This article suggests a new method for suppressing distortions by using the non-linearity current index (NLCI) to determine the shunt single-tuned passive filter (STPF) compensator value in non-sinusoidal power systems, with the objective of maintaining the power factor within desired limits. The objective of the proposed method is to minimize the nonlinear current of customer’s loads in the power system at the point of common coupling (PCC). Moreover, the proposed design takes into consideration other practical constraints for the total voltage and individual harmonic distortion limits, ensuring compliance with (Institute of Electrical and Electronics Engineers) IEEE 519-2014 guidelines, maintaining distortions at an acceptable level while also abiding by the capacitor loading constraints established in IEEE 18-2012. The performance of the optimally designed compensator is assessed using well documented IEEE standards based on numerical examples of nonlinear loads taken from previous publications.

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
P. M. Ivry ◽  
O. A. Oke ◽  
D. W. P. Thomas ◽  
M. Sumner

Various uncertainties arise in the operation and management of power systems containing Renewable Energy Sources (RES) that affect the systems power quality. These uncertainties may arise due to system parameter changes or design parameter choice. In this work, the impact of uncertainties on the prediction of harmonics in a power system containing multiple Voltage Source Converters (VSCs) is investigated. The study focuses on the prediction of harmonic distortion level in multiple VSCs when some system or design parameters are only known within certain constraints. The Univariate Dimension Reduction (UDR) method was utilized in this study as an efficient predictive tool for the level of harmonic distortion of the VSCs measured at the Point of Common Coupling (PCC) to the grid. Two case studies were considered and the UDR technique was also experimentally validated. The obtained results were compared with that of the Monte Carlo Simulation (MCS) results.


2020 ◽  
Vol 40 (3) ◽  
pp. 21-31
Author(s):  
Mohamed Nassim Kraimia ◽  
Mohamed Boudour

In this paper a study of the impact of the harmonics generated by a static Var compensator (SVC) is presented. The SVC is modeled, in the harmonic domain, as a coupled current source by using the complex Fourier transforms. Then, this model is converted to polar form to be integrated into the harmonic power flow program. This approach has been carried out on the IEEE 14 bus test power system, in order to show its effectiveness in evaluating the impact of harmonics, injected by the shunt compensating devices, and its interaction with the AC transmission system, in meshed power networks. Since the SVC consists of a thyristorcontrolled reactor (TCR) and a fixed capacitor, the harmonic currents are functions of the TCR thyristors firing angles. The variation of the total voltage harmonic distortion as function of firing angle changes and location of nonlinear loads is clearly presented and discussed.


2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Aida Fazliana Abdul Kadir ◽  
Tamer Khatib ◽  
Wilfried Elmenreich

This paper is an overview of some of the main issues in photovoltaic based distributed generation (PVDG). A discussion of the harmonic distortion produced by PVDG units is presented. The maximum permissible penetration level of PVDG in distribution system is also considered. The general procedures of optimal planning for PVDG placement and sizing are also explained in this paper. The result of this review shows that there are different challenges for integrating PVDG in the power systems. One of these challenges is integrated system reliability whereas the amount of power produced by renewable energy source is consistent. Thus, the high penetration of PVDG into grid can decrease the reliability of the power system network. On the other hand, power quality is considered one of the challenges of PVDG whereas the high penetration of PVDGs can lead to more harmonic propagation into the power system network. In addition to that, voltage fluctuation of the integrated PVDG and reverse power flow are two important challenges to this technology. Finally, protection of power system with integrated PVDG is one of the most critical challenges to this technology as the current protection schemes are designed for unidirectional not bidirectional power flow pattern.


IJOSTHE ◽  
2017 ◽  
Vol 4 (3) ◽  
pp. 6 ◽  
Author(s):  
Sarika Gautami ◽  
Rajeev Tiwari

Photovoltaic power generation refers to the use of solar photovoltaic cells to the solar radiation can be directly transformed into electricity generation. Distributed photovoltaic power generation, refers to the construction in the vicinity of the user's location, the operation mode to the user side of spontaneous self-occupied mainly, the excess power on the Internet, and in the distribution system to balance the characteristics of the photovoltaic power generation facilities. Distributed photovoltaic power generation follow the principle of local conditions, clean and efficient, decentralized layout, the principle of the nearest use, and make full use of local solar energy resources, alternative and reduce fossil energy consumption. This paper aims to investigate and emphasize the importance of the grid-connected PV system. The investigation was conducted to critically review the literature on expected potential problems associated with issues of PV based grid system. The main purpose of this paper is to discuss the basic understanding of photovoltaic (PV) based distributed generation power system and how these power flows will influence the performance and stability of a power system. Some of the PV grid integration issues such as voltage regulation, voltage sags, harmonic distortion, etc are also discussed and possible solutions are also mentioned.


Author(s):  
Amarjeet Singh

Problems associated with harmonic distortion are well understood for electrical power system applications.The right solution is challenging. There are numerous technologies to choose from, each with specific technical and economic advantages. This paper provides recommendations for reducing harmonic distortion, improving system capacity and improving system reliability. Special considerations for applying capacitors on a power systems with harmonics will be discussed.


2010 ◽  
Vol 2010 ◽  
pp. 1-13 ◽  
Author(s):  
Josef Tlustý ◽  
Jiří Škramlík ◽  
Jan Švec ◽  
Viktor Valouch

The procedure for calculating controller parameters of the APFs implemented into a multibus industrial power system for harmonic voltage mitigation is presented. The node-voltage-detection control strategy is applied and the basic controller parameters are found under the condition that the demanded THD factors at the buses where the APFs are placed will be obtained. A cooperative control of several APFs without mutual communication is proposed, simulated, and experimentally verified. By tuning the controller gains without considering the power circuit parameters, all APFs used tend to share harmonic load currents approximately equally regardless of the operation modes of the nonlinear loads in different parts of the power system.


2013 ◽  
Vol 724-725 ◽  
pp. 1393-1397
Author(s):  
Xiang Zhen Li ◽  
Guang Ming Hu ◽  
Peng Xin Hou ◽  
Yu Bo Fan ◽  
Chun Lin Guo

As a class of nonlinear loads in the power system, electric vehicle chargers will produce a certain harmonic pollution for the grid. Before the construction of charging stations, it is necessary for electric vehicle charger (station) connected to the grid to simulate and predict harmonics. The models of single charger and charge station are built separately in order to simulate and analysis the impact of a single and multiple chargers on power quality. The factors of the harmonic current ratio (HRI) and the current total harmonic distortion (THDI) varied with the charging power and the number of the chargers are discussed and analyzed. The generation mechanism of harmonic counteraction and interaction between the chargers are analyzed. The simulation results show that: because of the impedance of the system and the transformer, the harmonic current ratio (HRI) and the current total harmonic distortion (THDI) both increase firstly to some extent and subsequently decrease gently with the increase of the number of the chargers in the same power charging. This phenomenon has nothing to do with the harmonic counteraction and how that happen is discussed and analysis in this paper. And the phenomenon of harmonics interaction and counteraction occurs with the increase of the number of the chargers in different power charging, and the current total harmonic distortion (THDI) declines and tends to maintain a relatively stable value.


2018 ◽  
Vol 1 (1) ◽  
pp. 21-24 ◽  
Author(s):  
Fahri Vatansever ◽  
Nedim Aktan Yalcin

Increase in the number of nonlinear loads and devices in energy and power systems have raised harmonic distortion on voltage and current signals. Harmonics are one of the primary factors in determining power quality. Therefore, measurement and control of harmonics are crucial. Many methods have developed for harmonic analysis. In this study, a simulator which uses Hartley transform for determining harmonics is designed. Harmonic distributions and parameters of loaded/defined signals can be calculated accurately and effectively and obtained results can be displayed numerically and graphically with developed systems which have user friendly interface.


Author(s):  
Miloš Milovanović ◽  
Jordan Radosavljević ◽  
Bojan Perović ◽  
Milorad Dragičević

This paper presents the results of power flow calculations in the presence of harmonics in radial distribution systemsobtained using the decoupled harmonic power flow (DHPF) algorithm. In this algorithm, the interaction among the harmonicfrequencies is assumed to be negligible and hence the calculations are separately performed for every harmonic order of interest. Adetailed methodology for calculating current and voltage high order harmonics, harmonic losses and total harmonic distortion ofvoltage of the electrical distribution networks in the frequency domain is presented. The standard backward/forward sweep method isused for solving the power flow problem at the fundamental frequency. Furthermore, some practical and approximated models ofnetwork components in harmonic analysis are given. The performance of the DHPF approach is studied and evaluated on two standardtest systems with nonlinear loads, the distorted IEEE 18-bus and IEEE 33-bus. Nonlinear loads are treated as harmonic current sourcesthat inject harmonic currents into the system. The DHPF algorithm is verified by comparing its results with those generated bysoftware tools for the analysis of transmission, distribution and industrial power systems (i.g. ETAP and PCFLO). Simulation resultsshow the accuracy and efficiency of the applied procedure for solving the harmonic power flow problem.


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