Mustafa Engin Başoğlu

A new maximum power point tracking approach for decreasing convergence time

This study presents a new maximum power point tracking (MPPT) approach for solar panels. By using voltage current characteristic of solar panel, some analytical approaches have been developed. With the help of this approach, determination of initial operation point has been improved. In other words, this point has been determined by making some assumptions. Thus, one of the challenging tasks related to MPPT, convergence time is reduced. Benefits of developed approach have been shown by making a comparison with the Perturb and Observe (P&O) and Incremental Conductance (IC) algorithm. In this context, a low power boost converter has been designed with direct duty control in order to verify the proposed approach. Experimental results show that proposed approach performs better than conventional ones. While convergence time is high in case of P&O and IC usage, with proposed approach, it is reduced remarkably. Besides, steady state oscillation is almost eliminated in proposed approach.

Investigation of solar panel characteristics and MPPT performance under partial shading conditions

This paper presents an investigation study of solar panel characteristics under uniform solar irradiance and partial shading conditions (PSC) and an analysis for determining the global maximum power point (GMPP) of solar panel. As known, solar panel experiences multiple maximum power points (MPPs) if PSC occurs. Therefore, MPP tracking (MPPT) becomes harder compared with the uniform irradiance condition in case of usage of classical algorithms. In this regard, analyzes for uniform and PSC are made by using perturb and observe (P&O) algorithm in this study. By performing several simulations, behavior of the GMPP under PSC is aimed to detect accurately. With the help of these simulations, range of voltage (region for GMPP) can be estimated as user defined accuracy.

An enhanced scanning-based MPPT approach for DMPPT systems

ABSTRACT In this paper, an improved maximum power point tracking (MPPT) approach being low parameter dependency, simple structure and limited search interval has been presented for distributed MPPT photovoltaic (PV) systems. Basically, this approach is based on scanning of power–voltage (P-V) characteristic curve of PV modules in a limited duty ratio interval which makes tracking operation simple, fast and efficiently available in both uniform irradiance and partial shading conditions (PSCs). By limiting the scanning interval of maximum and minimum values of duty ratio via some analyses related to P-V characteristic for PSCs, global MPPT (GMPPT) is achieved in an efficient way. So as to validate performance of the proposed approach, a single-ended primary inductance converter has been used in both simulation and experimental studies. PV simulator has been used as a PV source to obtain different module characteristics with different number of bypass diodes and PV power levels. Both simulation and experimental results clarify that improved MPPT approach realises GMPPT effectively. Due to the high performance results, this approach can be an alternative technique in module-integrated converters, smart modules and PV power optimisers in which single module is used.

Experimental evaluations of global maximum power point tracking approaches in partial shading conditions

Maximum power point tracking (MPPT) under partial shading conditions (PSC) has been popular topic recently. In this paper, P&O algorithm, full scanning and large scanning methods and a novel method are evaluated experimentally. In order to compare the methods and algorithms considered, a single ended primary inductance converter (SEPIC) was set up. Experimental results show that P&O algorithm has show poor performance in PSCs. On the other hand, full scanning and large scanning methods manages to track global MPPT (GMPPT). Performance of large scanning method is outstanding than full scanning one since it limits the scanning interval.

Seasonal based energy performance analyzes of Cd-Te and c-Si photovoltaic modules

This paper presents a seasonal based comparative study about energy performances of c-Si and Cd-Te solar panels under same real weather conditions. For this purpose, two on-grid photovoltaic power systems (PPS) were installed on the different metal construction with same tilt angle and monitored between December 2013 and November 2014. Energy performance comparison has been carried out by using performance ratio (PR) and mean array efficiency (MAE) and energy performance index specified in IEC 61724, normalized energy and capacity factor (CF). It is shown that since temperature coefficient of power in Cd-Te is lower than that of c-Si, Cd-Te array performs better than another array. Some key result of this study can be summarized as follows: Generated energy of Cd-Te is higher than that of c-Si array by rate of 9.2%-10.8 within measurement period. In addition, due to the low dependency on temperature, PR, MAE and CF result in higher value than c-Si array as indicated in literature.

Hardware based comparison of buck-boost converter topologies in MPPT systems

This paper presents a hardware based comparison of buck-boost converter topologies in MPPT applications. Buck-boost converters perform perfectly compared with the other DC-DC converter topologies without voltage conversion limitations. Comparative analyzes of classical buck-boost, sepic and cúk converters are made in terms of tracking capability, number of components that are used for power stage of these converters, control requirements, whether current of photovoltaic (PV) module is continuous or discontinuous and difficulties of measurement PV module current. Several simulations are performed by using perturb and observe (P&O) algorithm in MATLAB/Simulink environment under different solar irradiation conditions to conduct this research. With the help of this study, a basic technical guide for converter selection in MPPT applications is proposed.

Design principles of and modelling self-sufficient green houses

Traditional houses consume electrical energy in AC form which is generated by thermal power plants or other energy sources that cause environmental pollution, CO2 emission and global warming. The most important parts of a green house are renewable energy sources like photovoltaic and wind based systems. In this work, our proposed green house generates electrical energy in DC form from photovoltaic panels and wind energy systems. The power capacity of a photovoltaic panel and a wind turbine generator is determined by the region. This paper presents some modelling principles of power generation units and some other electronic devices for traditional houses. Electrical appliances for household use are determined and daily load consumption scenarios are created by us. Design principles of a green house and KOU-Green House projects prominent contents are the main concerns of this publication and the most considerable details about the green houses are described.