Reduction of harmonic distortion in micro grids and distribution systems with photovoltaic generators

Author(s):  
K. Prasanna Kumar ◽  
R. Vanitha ◽  
S. Sai Hemesh
2021 ◽  
Vol 11 (2) ◽  
pp. 774 ◽  
Author(s):  
Ahmed S. Abbas ◽  
Ragab A. El-Sehiemy ◽  
Adel Abou El-Ela ◽  
Eman Salah Ali ◽  
Karar Mahmoud ◽  
...  

In recent years, with the widespread use of non-linear loads power electronic devices associated with the penetration of various renewable energy sources, the distribution system is highly affected by harmonic distortion caused by these sources. Moreover, the inverter-based distributed generation units (DGs) (e.g., photovoltaic (PV) and wind turbine) that are integrated into the distribution systems, are considered as significant harmonic sources of severe harmful effects on the system power quality. To solve these issues, this paper proposes a harmonic mitigation method for improving the power quality problems in distribution systems. Specifically, the proposed optimal planning of the single tuned harmonic filters (STFs) in the presence of inverter-based DGs is developed by the recent Water Cycle Algorithm (WCA). The objectives of this planning problem aim to minimize the total harmonic distortion (THD), power loss, filter investment cost, and improvement of voltage profile considering different constraints to meet the IEEE 519 standard. Further, the impact of the inverter-based DGs on the system harmonics is studied. Two cases are considered to find the effect of the DGs harmonic spectrum on the system distortion and filter planning. The proposed method is tested on the IEEE 69-bus distribution system. The effectiveness of the proposed planning model is demonstrated where significant reductions in the harmonic distortion are accomplished.


2019 ◽  
Vol 39 (2) ◽  
Author(s):  
Juan Martín Guardiola Montenegro ◽  
Eduardo Gómez Luna ◽  
Eduardo Marlés Sáenz ◽  
Jorge Armando De la Cruz Saavedra

Electrical networks are evolving and taking on more challenges as the inclusion of renewable energy and distributed generation units increase, specially at distribution levels. Big trends of generating electricity with alternative and renewable resources has promoted the formation of distribution networks subsystems or micro grids, capable of supplying their own electric demand and to export energy to the interconnected system, if necessary. However, the effects of these generation units into the network and into the microgrid as well are many, as harmonic distortion, voltage flickers and especially in electrical protections.This paper provides an overview about implementation of renewable energy and distributed generation worldwide, as well as an introduction to microgrids concept and its main impacts and challenges into the electric systems. Finally, the main impacts of microgrid on protection equipments are presented at a distribution level, being adaptive protections one of the solutions to the dynamic changes of the electric system.


Author(s):  
V. Lakshmi Devi ◽  
T. Phanindra

Electrical distribution system suffers from various problems like reactive power burden, unbalanced loading, voltage regulation and harmonic distortion. Though DSTATCOMS are ideal solutions for such systems, they are not popular because of the cost and complexity of control involved. Phase wise balanced reactive power compensations are required for fast changing loads needing dynamic power factor correcting devices leading to terminal voltage stabilization. Static Var Compensators (SVCs) remain ideal choice for such loads in practice due to low cost and simple control strategy. These SVCs, while correcting power factor, inject harmonics into the lines causing serious concerns about quality of the distribution line supplies at PCC. This paper proposes to minimize the harmonics injected into the distribution systems by the operation of TSC-TCR type SVC used in conjunction with fast changing loads at LV distribution level. Fuzzy logic system and ANN are going to be used solve this nonlinear problem, giving optimum triggering delay angles used to trigger switches in TCR. The scheme with Artificial Neural Network (ANN) is attractive and can be used at distribution level where load harmonics are within limits. Verification of the system and by using mat lab / simulink with proper modeling.


Author(s):  
Vijaya Anand N, Hema Latha J, G Devadasu, Kumar C

Distributed generation (DG) sources often interfaced with grid by a Cascaded H-bridge multilevel inverter with a remote D.C source. The interface inverter has to adapt voltage on the either side of the grid and DG source while it has a control of active and reactive power exchange. The inverter terminal voltage is maintained based on frequency switching technique. However, in applications like micro grids are based on quality of output voltage at the point of common coupling. The present paper discusses an optimal frequency switching methodology that generates optimal fringing angle based on an evolutionary computing technique while maintaining the voltage level at PCC with a reduced harmonic distortion.  Efficacy of the proposed method is illustrated by simulating a 9-level cascaded H bridge in MATLAB environment.


Single-Phase AC-DC-AC converters are employed in vast of applications such as UPS Systems, Motor Drives, Yaw Drives, Traction and Micro Grids. This paper introduces an incipient topology for multilevel inverter based Single-Phase AC-DC-AC converter for different types of loads. The suggested converter consists of two phases; a full bridge rectifier that converts AC supply to DC supply and a multilevel inverter that converts DC supply to AC supply cascaded into a rectifier. For the proposed system, the multilevel inverter is chosen as it raises the voltage output level and thus diminishes the Total Harmonic Distortion (THD). The converter suggested here effectively reduces the harmonics in the output voltage and using Multilevel Inverter, reduces THD in the AC-DC-AC converter. The simulation outcomes are acquired from MATLAB® Simulink platform and a hardware prototype of the inverter is done.


Sign in / Sign up

Export Citation Format

Share Document