Solar Engineering Of Thermal Processes

Learning And Soft Computing Support Vector Machines Neural Networks And Fuzzy Logic Models

SPICE est un logiciel qui m’a beaucoup émerveillé lorsque j’étais étudiant, de par sa puissance et sa simplicité d’utilisation. Il est vrai que nous faisions beaucoup de travaux pratiques en électronique, et le simple fait de pouvoir mettre son circuit sous forme de liste, appelée netlist, et de le simuler était une découverte fascinante. SPICE a servi de modèle à nombre d’autres programmes de simulation, dans les universités et dans l’industrie, grâce à son modèle précoce Open Source. Aujourd’hui toute l’électronique se concentre sur une puce, et les logiciels de simulation utilisés sont plutôt du type VHDL [1], voire mixte continu/événementiel [2], mais dont la plupart sont inspirés de SPICE. Actuellement, on édite de manière graphique son schéma et on lance directement la simulation depuis son interface graphique. Ce qu’il faut savoir c’est que bon nombre de ces interfaces graphiques construisent une netlist et c’est un SPICE adapté qui fera la simulation par-derrière. La première version de SPICE date de 1972 et a été écrite en fortran, rapidement suivie par la deuxième version en 1975. Il faudra attendre 1989 pour voir la troisième version (définitive) de SPICE, écrite en C. Il est remarquable d’observer que la troisième version fût la dernière, avec des mises à jour mineures et qui se déclinent en lettre, la dernière étant 3f5. Aujourd’hui, et dans cet article, on utilisera Ngspice [3] qui est basé sur la dernière version de SPICE, et qui se trouve sous licence GNU GPL2. Il est fourni par le groupe de développement gEDA [4] qui a repris le flambeau pour le développement de tous les logiciels de simulation ou de conception de circuits électroniques.

SPICE – Simulation Program with Integrated Circuit Emphasis

Estimation of daily global solar radiation using deep learning model

A novel statistical performance evaluation of most modern optimization-based global MPPT techniques for partially shaded PV system is presented in this paper. In recent years, there has been a growing attention toward mitigation of partial shading effect of the PV system through using modern optimization. The field of tracking MPP of the PV system attracts huge attention from the researchers, as it is the best way to increase PV plant efficiency. Under non-uniform solar irradiance, the power against voltage characteristics of PV array have more than one MPP. This condition leads to extra complications to track MPP and decreases the efficiency of the PV system. Traditional MPPT methods are typically used to increase the harvested energy of PV under normal conditions without any problems. The key drawback of such methods is failing extraction of global MPP under actual weather conditions that sometimes under shadowing condition. Several global MPPT methods based on modern optimization are presented for extracting global MPP in case of shadowing condition. The essential target of this work is not limited to present an integrated specific review on the state-of-the-art of these techniques; but also a comprehensive statistical evaluation of twenty optimizers that represent high percent of all the reported techniques is performed with changing shading scenarios. This work serves as a source of valuable information for researchers and engineers working with PV systems to keep abreast with the modern advance in the field of tracking MPP of PV system.

A novel statistical performance evaluation of most modern optimization-based global MPPT techniques for partially shaded PV system

Power electronic converter (PEC)-interfaced renewable energy generators (REGs) are increasingly being integrated to the power grid. With the high renewable power penetration levels, one of the key power system parameters, namely reactive power, is affected, provoking steady-state voltage and dynamic/transient stability issues. Therefore, it is imperative to maintain and manage adequate reactive power reserve to ensure a stable and reliable power grid. This paper presents a comprehensive literature review on the reactive power management in renewable rich power grids. Reactive power requirements stipulated in different grid codes for REGs are summarized to assess their adequacy for future network requirements. The PEC-interfaced REGs are discussed with a special emphasis on their reactive power compensation capability and control schemes. Along with REGs, conventional reactive power support devices (e.g., capacitor banks) and PEC-interfaced reactive power support devices (e.g., static synchronous compensators) play an indispensable role in the reactive power management of renewable rich power grids, and thus their reactive power control capabilities and limitations are thoroughly reviewed in this paper. Then, various reactive power control strategies are reviewed with a special emphasis on their advantages/disadvantages. Reactive power coordination between support devices and their optimal capacity are vital for an efficient and stable management of the power grid. Accordingly, the prominent reactive power coordination and optimization algorithms are critically examined and discussed in this paper. Finally, the key issues pertinent to the reactive power management in renewable rich power grids are enlisted with some important technical recommendations for the power industry, policymakers, and academic researchers.

Reactive Power Management in Renewable Rich Power Grids: A Review of Grid-Codes, Renewable Generators, Support Devices, Control Strategies and Optimization Algorithms

In this paper, all the models of PV cell, namely ideal single-diode model, single-diode $$R_{\rm s}$$
 model, single-diode $$R_{\rm p}$$
 model, the two-diode model, and the three-diode model, have been discussed. SPICE simulation is done to evaluate the impact of model parameters on the operation of PV cell. The effects of the parameters are discussed. The photocurrent, $$I_{\rm L},$$
 is proportional to irradiance, and the series resistance, $$R_{\rm s},$$
 reduces the short-circuit current and fill factor. The parallel resistance, $$R_{\rm p},$$
 reduces the open-circuit voltage, and both the diffusion diode and recombination diode reduce the open-circuit voltage value and fill factor. Finally, it is shown that an increase in cell operating temperature reduces the open-circuit voltage and fill factor and thus degrades the performance significantly.

/pdf/effect-of-various-model-parameters-on-solar-photovoltaic-46tiprogwh.pdf

Effect of various model parameters on solar photovoltaic cell simulation: a SPICE analysis

Techno-economic analysis and challenges of solar powered pumps dissemination in Bangladesh

Pure and fresh water is being scarce day by day. Although Bangladesh is a riverine country, pure drinking potable water is not a cheap commodity. Most of the people in the cities boil water to drink, and people of the villages take tube-well’s water directly, which might have high amount of heavy metal like arsenic. Solar still is a cheap and very useful renewable technology, which can be used in Bangladesh extensively everywhere at the rooftop as a pure water source. Objective of this paper was to find a low cost portable and easily maintainable passive solar still for southern part of Bangladesh. All the parameters of passive solar still are studied, and it is found that an inclined stepped solar still with passive condenser, internal and external reflectors, black cotton wick, and with optimum design values can be the desired still, which would give maximum yield. Finally, the optimum values of the parameters are used to propose a cheap design.

/pdf/a-review-of-optimum-parameter-values-of-a-passive-solar-1ukwokkst2.pdf

A review of optimum parameter values of a passive solar still and a design for southern Bangladesh

In this study, an analysis of the monthly mean values of the fraction of the sky covered by clouds (C) of all types and the duration of bright sunshine hours (S) and global solar radiation on the horizontal surface (H) was carried out to establish relationship for solar radiation estimation for Bangladesh. The relationship between C and (1 − S/S
 0), where S
 0 is the maximum possible hours of sunshine, was found to be nonlinear. The relationship between C and (1 − H/H
 0), where H
 0 is the extraterrestrial solar radiation, was also found to be nonlinear. Few quadratic regression equations were derived for different regions of Bangladesh. The data were separated in Zone 1 (below the tropic of cancer, i.e., ≤23.5°N) and Zone 2 (above the tropic of cancer, i.e., ≥23.5°N). All the developed models were checked statistically. It was found that it is always better to estimate solar radiation from sunshine duration as it gives the best estimation and accuracy, but if there is no sunshine duration data available for a site, then solar radiation can be estimated directly from cloud cover data. Estimating sunshine duration first from cloud data to estimate solar radiation introduces more error as it has to go through the modeling stage twice. In case of the need of sunshine duration data only, the estimation from cloud cover is quite helpful. It was also found from the study that for small country like Bangladesh separating data according to latitude has insignificant effect.

/pdf/estimation-of-solar-radiation-from-cloud-cover-data-of-4pz2kgqhtv.pdf

Md. Nazmul Islam Sarkar

Papers

Reactive Power Management in Renewable Rich Power Grids: A Review of Grid-Codes, Renewable Generators, Support Devices, Control Strategies and Optimization Algorithms

Effect of various model parameters on solar photovoltaic cell simulation: a SPICE analysis

Techno-economic analysis and challenges of solar powered pumps dissemination in Bangladesh

A review of optimum parameter values of a passive solar still and a design for southern Bangladesh

Estimation of solar radiation from cloud cover data of Bangladesh