MPPT Schemes for PV System Under Normal and Partial Shading Condition: a Review

The photovoltaic system is one of the renewable energy device, which directly converts solar radiation into electricity. The I-V characteristics of PV system are nonlinear in nature and under variable Irradiance and temperature, PV system has a single operating point where the power output is maximum, known as Maximum Power Point (MPP) and the point varies on changes in atmospheric conditions and electrical load. Maximum Power Point Tracker (MPPT) is used to track MPP of solar PV system for maximum efficiency operation. The various MPPT techniques together with implementation are reported in literature. In order to choose the best technique based upon the requirements, comprehensive and comparative study should be available. The aim of this paper is to present a comprehensive review of various MPPT techniques for uniform insolation and partial shading conditions. Furthermore, the comparison of practically accepted and widely used techniques has been made based on features, such as control strategy, type of circuitry, number of control variables and cost. This review work provides a quick analysis and design help for PV systems. Article History: Received March 14, 2016; Received in revised form June 26th 2016; Accepted July 1st 2016; Available online How to Cite This Article: Sameeullah, M. and Swarup, A. (2016). MPPT Schemes for PV System under Normal and Partial Shading Condition: A Review. Int. Journal of Renewable Energy Development, 5(2), 79-94. http://dx.doi.org/10.14710/ijred.5.2.79-9

Interfacing of battery with a medium voltage DC-DC converter using MATLAB/Simulink

Master of ScienceDepartment of Electrical and Computer EngineeringSanjoy DasNoel SchulzElectrical power, although convenient form of energy to distribute and use, cannot easily be stored in large quantities economically. Most electrical power generated by utility plants is consumed simultaneously in real time. However, in some cases, energy storage systems become crucial when power generated from sources does not fulfill peak power load demand in a power system or energy storage systems are needed as backup. Due to these reasons, various technologies such as batteries, ultracapacitors (UC), superconducting magnetic energy storage (SEMS) and flywheels are beneficial options for energy storage systems. Shipboard power systems must use one or more energy storage systems in order to backup the existing power system if locally generated power is unavailable. This will lessen the effect of voltage sags on power quality, and improve system reliability. This report mainly focuses on the design of a Boost DC-DC converter and the integration of that converter with a previously designed battery storage model, as well as the effect of varying loads at the end of the converter

Manual for Automation of Dc-microgrid Component Using Matlab/Simulink and FPGA\u27s

Solar Energy is one of the abundantly available renewable energy source. Solar panels are semiconductor materials which capture the solar energy from every band in the visible light spectrum, infrared spectrum and ultra violet spectrum and converts it into electrical energy. The DC community microgrid is used to supplement utility electrical power supplied to the neighbored with renewable sources such as solar panels, emergency back-up power through batteries or generators. Smart Cloud Interconnected environment increases the standard of living and facilitates ease to rectify faults, debug components and reinstate or replace obsolete components with newer ones. Automation of the DC microgrid components provides a simple yet efficient way to connect to the grid and to every component in the grid remotely. It is essential to find the node of failure in the grid for technicians and engineers to work on and to debug the issue to facilitate smooth running of the grid without shutdown. FPGAs are used as target devices for end synthesis of the model that is created on Simulink. These FPGAs are links between cloud and power electronics components. To utilize the energy resource efficiently we need to monitor the input and output of every component at every node in the grid. Simulating models on Simulink will let us connect the component and test engineer to the grid to detect any flaws or failures on time. FPGAs are easily reprogrammable and have long life with excellent capability to withstand stress. This thesis report provides a set of procedures to create and simulate a real time component model and to generate HDL files to build a clean code which can be redeployed on target FPGAs

Firefly algorithm tuning of PID position control of DC motor using parameter estimator toolbox

This paper aims to design an accurate angular position control for DC motors using a proportional integral derivative (PID) controller. The estimated DC motor parameters have been calculated using the parameter estimator toolbox in MATLAB, Arduino Mega 2560 and speed sensor to build an accurate model in MATLAB. The optimized PID coefficients are found for the DC motor model using the firefly algorithm (FA), which aims to make the actual angle match the desired value without overshooting and oscillations. The PIC16F877A microcontroller was used to implement the code based on optimized PID coefficients found in MATLAB/Simulink to generate the suitable pulse width modulation (PWM) output. In this work, step input was tested to analyze the characteristics of the system response in terms of rise time, settling time and overshoot. It was found that the controller output response curve which is produced from FA-based-PID reached the desired position without overshoot and any oscillations. The findings established that closed-loop control of any system using a system identification toolbox and optimized PID technique can be applied in real applications using low-cost controllers and sensors such as PIC16F877A microcontroller and analog rotary position sensor, respectively

Intelligent voltage regulator for distributed generation-based network

Power grids are being transformed into a smart distribution network that incorporates multiple distributed energy resources (DERs), ensuring stable operation and improved power quality at the same time. Many research papers have been published in recent years that discuss the voltage violation issues that emerge from the high penetration of distributed generation (DG). In this paper, we propose a new optimal voltage control technique based on feedforward neural networks (FFNN) to maintain a stable voltage profile. MATLAB®/Simulink® has been used to carry out the simulation. The simulation results show the efficiency of this method in voltage control. The proposed approach ensured a stable voltage profile for the considered schemes

Fault-resilient Control Strategy for Cascaded Multilevel Inverters in Grid-connected PV Systems

This paper presents a fault-tolerant control strategy for a three-phase, seven-level Cascaded Multilevel Inverter (CMI) in grid-connected photovoltaic (PV) systems. The proposed approach enhances state-of-the-art CMI fault-tolerant control by integrating advanced compensation techniques, combining fault isolation and compensation, and conducting a comprehensive system analysis under fault conditions. The study focuses on improving power quality and system robustness, making it particularly suitable for modern grid-tied renewable energy applications. Compared to previous works, this research offers notable advances in power quality, system reliability, and fault resilience. Key innovations include optimizing the use of renewable energy in large-scale solar installations through multilevel inverter technology and addressing operational faults to ensure uninterrupted power delivery. The findings underscore the significance of robust fault-tolerant strategies in improving the performance and stability of renewable energy systems

Application of differential power processing to photovoltaic modules under partial shading conditions

LAUREA MAGISTRALENegli ultimi tempi uno degli argomenti più discussi a livello globale è quello del cambiamento climatico dovuto al continuo aumento delle emissioni di sostanze inquinanti. Per ridurre l'aumento della temperatura globale e le conseguenze di questo fenomeno si stanno studiando a fondo le fonti di energia rinnovabile, e negli ultimi anni si è assistito ad una sempre maggiore diffusione di impianti, di varie dimensioni, per la produzione di energia da fonti energetiche rinnovabili. Aumentare la percentuale di energia generata con fonti rinnovabili è importante, ma è anche importante farlo nel modo più efficiente. Tra le diverse tipologie di produzione di energia verde, gli impianti fotovoltaici stanno avendo un forte incremento nel numero di installazioni, soprattutto in impianti di piccole dimensioni come quelli utilizzati a livello domestico. È importante, soprattutto con questi tipi di impianti, avere la massima efficienza possibile per fornire l'energia necessaria agli occupanti degli edifici, anche in condizioni ambientali non ottimali. Uno dei principali ostacoli agli impianti fotovoltaici è l'ombreggiamento parziale: anche una piccola ombra su uno o più sottomoduli può influire sulla produzione complessiva del modulo. Nei più comuni moduli fotovoltaici moderni, i sottomoduli sono dotati di un diodo di bypass che isola i sottomoduli ombreggiati, o parzialmente ombreggiati, per evitare che influiscano negativamente sugli altri sottomoduli. Questa soluzione aiuta a migliorare la produzione di energia, ma non permette di estrarre l’energia prodotta dai sottomoduli parzialmente ombreggiati. È chiaro che anche la più piccola quantità di energia è importante e non deve essere sprecata. In questa tesi sono state studiate diverse soluzioni per aumentare l'efficienza dei moduli fotovoltaici in condizioni di ombreggiamento parziale. In particolare, è stato fatto un approfondimento sull'applicazione di sistemi di Differential Power Processing (DPP) sui moduli fotovoltaici in alternativa ai diodi di bypass.In the recent times one of the most discussed topics at global level is the climate changes due to a continuous increase of pollutants’ emissions. To reduce the increasing global temperature and the climate changes the renewable energy sources are getting investigated deeply, and the recent years have seen an even more spreading of plants, of different sizes, for energy production from renewable energy sources. It’s significant to enhance the percentage of energy generated with renewable sources, but it’s also important to make it in the most efficient way. Among the different types of green energy production, the photovoltaic systems are having a big increase in number of installations, especially in small size plants like the ones used at domestic level. It’s important, especially with these types of systems, to have the best efficiency as possible to provide the required energy to the occupants of the buildings even under not optimal environmental conditions. One of the main obstacles to the PV systems is the partial shadowing: even a small shadow over one or more submodules can affect the overall module’s production. In the most common modern PV modules, the submodules are equipped with a bypass diode, which cut off the shadowed, or partially shadowed, submodules to avoid that it affects the other submodules. This solution helps to improve the energy production, but it cuts off the amount of energy produced by partially shadowed submodules. For an ever more efficient power production it’s important to not waste even the smallest amount of energy. In this thesis, different solutions to increase the efficiency of the PV modules under partial shadowing are investigated. In particular, a focus on the application of Differential Power Processing (DPP) systems on PV module as an alternative to the bypass diodes has been made

Analysis of ANFIS MPPT Controllers for Partially Shaded Stand Alone Photovoltaic System with Multilevel Inverter

This work presents a unique combination of an boost converter  run by a set of two photovoltaic panels (PV) with a MPPT, suitable to guarantee MPP even under partial shadowed conditions, managed by an adaptive neuro fuzzy inference system (ANFIS) trained by the training data derived from a Perturb and observation (P&O) conventional algorithm. The single phase cascaded H bridge five-level inverter (CHI) driven by the individual outputs of the boost converter, with selective harmonic elimination scheme to eliminate typically the seventh order harmonics. Simulation was carried out in the MATLAB/SIMULINK environment validated the proposed scheme. It has been thus established; by both simulations the ANFIS model of MPPT scheme outperforms other schemes of conventional control algorithm

Design and implementation of a dual-input single-output photovoltaic converter

In many solar inverters, a dc/dc converter is mainly located between the solar arrays and the inverter. This study presents an enhanced maximum power point tracking (MPPT) algorithm for photovoltaic (PV) systems that drives solar array voltages to track a reference value and decreases fluctuations and oscillations in PV voltage. Different from the previously presented methods, a novel MPPT method is proposed that ensures tracking accuracy by considering output voltage in addition to input voltage and currents. The proposed method detects dI/dV variations, compares the output voltage with the desired reference to shift operation mode and refreshes step size. The digital filtering, enhanced PI, and perturb-and-observe (P&O) tracking features of the proposed MPPT method make it robust to mitigate source fluctuations and sensitivity to partial shading based oscillations. In order to validate the success of the proposed method, a test rig has been installed with dual boost converters. The performance improvements have been verified by both simulation and experimental results that are compared to InCon and P&O MPPT methods. It is also confirmed by experimental results that the proposed MPPT method provides robust control capability in terms of tracking the reference voltage and rejecting the effects of various shading situations on solar arrays

Intelligent Methods for Smart Microgrids

This paper summarizes ongoing research in the application of intelligent methods to the design, modeling, simulation and control of microgrids including optimal design of microgrids, and centralized and decentralized control. © 2011 IEEE