Photovoltaic Renewable Energy Research Articles

Nonlinear Control Design for Maximum Power Point Tracking and Unity Power Factor of a Grid-Connected Photovoltaic Renewable EnergySystems

This paper deals with the design of a nonlinear controller for single-phase grid-connected photovoltaic (PV) renewable energy systems to maintain the current injected into the grid in phase with grid voltage and to regulate the DC link voltage and to extract maximum power point tracking (MPPT).The system configurationincludes a photovoltaic generator, DC-DCconverter, DC-AC inverter coupled to grid network. The controller is designed using thebackstepping control to optimize the PV energy extraction and to achieve unity power factor, the controller is based on an averaged nonlinear state space model of the controlled system. This is carried out via controlling the duty ratio of the DC-DC converter and DC-AC inverter. An integral action was added in order to robustify the controller with respect to parameter variations and disturbances.The synthesis of the regulator wasachieved by having recourse to advanced tools of nonlinearcontrol such as asymptotic stability in the sense of Lyapunov. The performance of the proposed controller is evaluated through numerical simulation in terms of delivering maximum power and synchronization of grid current with grid voltage under changes in atmospheric conditions.

Design of a Photovoltaic System as an Alternative Source of Electrical Energy for Powering the Lighting Circuits for Premises in Ghana

This paper seeks to emphasise the tendency of the use of solar energy as an alternative source of energy for today as far as the lighting needs of a particular infrastructure is concerned. It compares the use of a Photovoltaic (PV) System and an existing 60 kVA generator that powers a premise. The paper provides a general understanding of a solar energy (renewable energy) and how photovoltaic technology can be practically applied to power the lighting needs of the premise. Analysis of the site, weather data, and the design predicted the value of the photovoltaic system as an economic investment. We present the analysis undertaken using the PVSYST software package to optimize the system design for the premise. The simulation and calculation was done with the consideration of a PV array’s tilt and direction and economic considerations. The proposed photovoltaic system for the premise, with 30 units of battery capacity of 17850 Ah, an inverter size of 132 kW and a minimum number of 8 modules at 12.53 kWp was sufficient for the proposed design. The output analysis when implemented will result in a substantial lifetime energy savings, improving reliability and provide a great impact on the environment. It is therefore worthwhile to invest in photovoltaic renewable energy systems to augment the energy needs of locations where its use is viable.

Low Power Passive Photovoltaic System Development to Assist Inconvenient Grid Connection Locations

Sun radiation is known as one of the cleanest energy available and free maintenance on the earth to support the extensive demand for electrical power requirement for large and small scale. This energy is known as most promising renewable energy available during the whole year. This fact has shown a very strong interest among the researchers, industries and consumers to develop technology and system that can harvest solar energy to electrical energy. A lot of researches have been done to explore the capability of sun as natural energy source which is capable to provide huge alternative support to the increasing demand of electrical power in society. All the research findings have been adaptively combined to design, develop and structure as a reliable finished product for end users implementation. The fast improving research in photovoltaic application has proven that photovoltaic renewable energy is considered as one of the most promising source to support the increasing demand in electrical utilization. Advantages implementing the photovoltaic technology will benefit during the fuel price increment and be insufficient of the non-renewable energy to support the increasing demand from the society. Looking into this factor, many industries have developed the electrical photovoltaic system in large, medium and small scale for implementation. Electricity is becoming an essential requirement because of the increasing demand for electrical power from the society. Due to the increasing demand for electrical power, many researches are conducted to support the conventional way of generating electricity. This research has explored many other available abundant renewable energy resources such as solar, wind and thermal which are largely available to support the increasing demand. In this research, researchers discovered that the solar energy is the main contributor to support the increasing demand for electricity. The research outcome has helped the industries to develop solar power photovoltaic systems. This paper discusses the approaches to design and develop a real-time 500 Watt DC to AC Solar Power System. The system capability to store the harvested energy is discussed in this paper.

Performance evaluation of a stand-alone photovoltaic system on an isolated island in Hong Kong

Currently one of the most promising power solutions for remote rural areas and isolated islands which are far away from utility grid is the stand-alone solar photovoltaic (PV) renewable energy system or hybrid solar–wind power system. This paper presents the investigation results of a real remote solar PV project on an island in Hong Kong. The stand-alone PV system, rated at 19.8kWp, is established on a remote island for power generation to local residents. Power on this island was originally supplied by diesel generators and this new solar energy system has significantly reduced fuel costs and alleviated environmental pollution. The on-site entire system’s operating data was collected for one whole year in 2011, and the energy performance of the PV array, inverters, battery bank and the entire PV system were analyzed in terms of daily energy balance, normalized performance parameters and overall system energy utilization ratio. The results from this long term system monitoring and its evaluation enables a detailed inspection of system operating performance with respect to the technical issues, which provides a useful reference for future applications of solar photovoltaics in remote islands.

Control of Chaotic Behaviour in Parallel-Connected DC-DC Boost Converters

Chaos control means to design a controller that is able to eliminating the chaos behaviour of nonlinear systems that experiencing such phenomenon. In this paper, a delayed feedback control mode is presented. The paper describes the control of the bifurcation behaviour of a modular peak current-mode controlled DC-DC boost converter which is used to provide an interface between energy storage batteries and photovoltaic (PV) arrays renewable energy sources. The parallel-input/parallel-output converter comprises two identical boost circuits and operates in the continuous-current conduction mode. A comparison is made between waveforms obtained from a MATLAB/SIMULINK model for open-loop converter and the controlled one. The study shows the effectiveness of the designed delayed feedback control mode.

Green Innovation in Energy: Product, Process and Business Innovation Gains for Competitive Advantage

AbstractThe paper addresses the �green innovation� in the non-fossil fuel energy industry. The objective of the study is to identify the changes in trends of non-fossil fuel energy industry demand, growth and opportunities. The study uses the databases such as patents, news events, income/financial statements to assess the company status and the track record of the industry. The research adopts the methodology of Innovation Radar (Sawhney, MIT Sloan Management Research, 2001) to assess the positioning of the dominant company and design in photovoltaic, geothermal and wind renewable energy industry. The study also summarizes the sustainable competitive advantages of some of the successful companies in the energy sector. This study correlates the gains in innovation tripartite (product, process, business) to the corporate competitive advantage. The companies selected in this study are based on the innovations brought to improve the product, process and business aspects and are evaluated in terms of market adaptability.

Photovoltaic deployment strategy in Japan and the USA—an institutional appraisal

Photovoltaic (PV) is a renewable energy technology, along side with other modular energy generation technologies such as micro-turbines, fuel cells, etc., which will enable the alternative distributed generation paradigm compared to the incumbent fossil fuel based centralized generation paradigm. Distributed generation utilizing renewable energy resources offers opportunities for significant carbon dioxide and emissions reductions thus contributing solutions to broader climate change issues. Yet, renewable energy technologies like PV face various barriers for their widespread adoption. Aside from technical and cost issues, renewable technologies have to overcome the so-called carbon lock-in effects. This refers to the techno-institutional complex associated with the fossil-fuel based centralized generation regime that currently dominates energy production and use. Governmental interventions to address these issues usually can be seen as composed of research, development, demonstration and deployment or RD3 [PCAST, 1999. Panel on International Cooperation in Energy Research, Development, Demonstration, and Deployment]. This paper focused on comparing the deployment aspect of PV technology in Japan and the USA. While both governments promoted PV as part of their larger strategies to address various environmental and energy security issues, Japan has built a PV installation capacity three times that of the USA as of December 2003 with over 90% of PV installation in the grid-connected small residential system category. This is in marked contrast to the case in the USA in which the cumulative installation is spilt among different types of applications involving the grid and off the grid. We put forward two models to explain these differences in deployment strategies and their possible consequences. The first deployment model leverages upon PV as a manufactured technology with minimal customization to achieve massive deployment. The second deployment model leverages upon PV as an information technology-like technology focusing upon user oriented customization to achieve deployment. Different models have different implications to the system engineering aspect of solar PV. A focus upon the standard grid-connected distributed category in the residential setting avoids the heavy customized engineering associated with many off-grid and one-off type projects. Japanese PV deployment strategy of concentrating upon a dominant category or niche with mass market potential also well matches the institutional structure of production [Coase, 1991. The Institutional Structure of Production, in Essays on Economics and Economists. The University of Chicago Press, Chicago] within the local PV technology suppliers industry. Major vertical integrated firms can facilitate system-related learning easier than a fragmented industry within the PV value chain with minimal transaction cost. This highly suggests that deployment strategy of PV or other renewable energy technologies must address the issues of adopting a globally developed technology to local (national) conditions and has strong institutional underpinnings in addition to financial subsidies, learning investment thinking.

Ten years of collaborative photovoltaic research and education: University of Florence—Slovak University of Technology

This paper deals with research and development (R&D) activities in the area of photovoltaic (PV) renewable energy within collaboration between the Slovak University of Technology, Bratislava and University of Florence. Activities covered include the development of all-implanted monocrystalline silicon cells with screen-printed contacts, PV modules technology for the manufacture of large-area components for power roofs, building and acoustic barriers applications, power conditioning for PV supply units for railway applications, and technological solutions for the realization of PV arrays operating at direct-current voltages in excess of 500 V. Other activities have been related to CdTe thin films for solar cells. Educational activities in the field of photovoltaic engineering for an undergraduate course are briefly outlined as well.