This paper presents results obtained from monitoring a 1.72 kWp photovoltaic system installed on a flat roof of a 12 m high building in Dublin, Ireland (latitude 53.4°N and longitude 6.3°E). The system was monitored between November 2008 and October 2009 and all the electricity generated was fed into the low voltage supply to the building. Monthly average daily and annual performance parameters of the PV system evaluated include: final yield, reference yield, array yield, system losses, array capture losses, cell temperature losses, PV module efficiency, system efficiency, inverter efficiency, performance ratio and capacity factor. The maximum solar radiation, ambient temperature and PV module temperature recorded were 1241 W/m2 in March, 29.5 °C and 46.9 °C in June respectively. The annual total energy generated was 885.1 kW h/kWp while the annual average daily final yield, reference yield and array yield were 2.41 kW h/kWp/day, 2.85 kW h/kWp/day and 2.62 kW h/kWp/day respectively. The annual average daily PV module efficiency, system efficiency and inverter efficiency were 14.9%, 12.6% and 89.2% respectively while the annual average daily performance ratio and capacity factor were 81.5% and 10.1% respectively. The annual average daily system losses, capture losses and cell temperature losses were 0.23 h/day, 0.22 h/day and 0.00 h/day respectively. Comparison of this system with other systems in different locations showed that the system had the highest annual average daily PV module efficiency, system efficiency and performance ratio of 14.9%, 12.6% and 81.5% respectively. The PV system’s annual average daily final yield of 2.4 kW h/kWp/day is higher than those reported in Germany, Poland and Northern Ireland. It is comparable to results from some parts of Spain but it is lower than the reported yields in most parts of Italy and Spain. Despite low insolation levels, high average wind speeds and low ambient temperature improve Ireland’s suitability.

Measured Performance of a 1.72 kW Rooftop Grid Connected Photovoltaic System in Ireland

Z-Source Inverterの性能評価に関する検討

Transformer-less inverters are necessary parts for grid-connected renewable energy resources. Owing to its cost effectiveness, downsize and less weight, great attention has been paid to these inverters development. With these aforementioned advantages, these inverters have limitations like the flow of leakage current through photovoltaic arrays, high total harmonic distortion (THD) at inverter's output and DC current injection to the grid. This study presents coupled inductor-based single-phase transformer-less semi-Z-source inverter topology to lessen those limitations. Since the DC input and AC output voltage share a common ground, the presented inverter system is categorised under doubly grounded topologies. For the purpose of handling, the non-linearity of the voltage gain of semi-Z-source inverter, a non-linear sinusoidal pulse-width modulation technique has been employed. The prototype of the suggested inverter has been constructed. The performance and compatibility of modulation technique are verified under different loading conditions. The feasibility of the configuration is ensured based on the mitigated common-mode leakage current, the substantially lower THD as well as DC current injected to the grid. Moreover, the presence of coupled inductor significantly contributes in reducing input current ripple, installation area of the inverter and enhancing the efficiency. Finally, this topology exhibits appreciable performance to operate synchronously and transfer power to the grid.

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Semi-Z-source inverter topology for grid-connected photovoltaic system

Exergo-economic assessment and sensitivity analysis of a solar-driven combined cooling, heating and power system with organic Rankine cycle and absorption heat pump

We present a review of the current state of the field for a rapidly evolving group of technologies related to solar energy harvesting in built environments. In particular, we focus on recent achievements in enabling the widespread distributed generation of electric energy assisted by energy capture in semi-transparent or even optically clear glazing systems and building wall areas. Whilst concentrating on recent cutting-edge results achieved in the integration of traditional photovoltaic device types into novel concentrator-type windows and glazings, we compare the main performance characteristics reported with these using more conventional (opaque or semi-transparent) solar cell technologies. A critical overview of the current status and future application potential of multiple existing and emergent energy harvesting technologies for building integration is provided.

Recent Developments in Solar Energy-Harvesting Technologies for Building Integration and Distributed Energy Generation

Reconfigurable solar photovoltaic systems: A review.

Need for alternative energy sources to satisfy the rising demand in energy consumption elicited the research in the area of power converters/inverters. An increasing interest of using Z source inverter/converter in power generation involving renewable energy sources like wind and solar energy for both off grid and grid tied schemes were originated from 2003. This paper surveys the literature of Z source inverters/converter topologies that were developed over the years.

https://beei.org/index.php/EEI/article/viewFile/579/888

Z Source Inverter Topologies-A Survey

The performance of Z source DC/DC converter topologies such as, traditional and Quasi Z source based DC/DC converter (both single and three phase) are analysed, and adopted at the front end of a power conditioning unit for DC power supply system. Various switching schemes like, simple boost PWM, carrier based PWM and space vector PWM control techniques are adopted to control the inverter switches. A new Quasi Z-source network based DC/DC converter topology employing Zigzag transformer is proposed. Transformers either, linear and/or zigzag are implemented individually, for step up as well as isolation functions. Voltage Doubler Rectifier (VDR) circuit is adopted to convert the high ac voltage from the transformer to dc voltage. Simulations are carried out in MATLAB/SIMULINK environment and the results are found to be promising for all the above switching schemes.

Comprehensive analysis of Z source DC/DC converters for DC power supply systems

This paper deals with the topological analysis of a novel improved three-level Z-source inverter. By connecting a Z-source network to the rear end of the existing three-level inverter, it produces ...

Novel improved three-level Z-source inverter

This paper investigates the performance of a new family of extended-boost quasi Z Source inverters (qZSI), such as diode, capacitor assisted and its combination ie hybrid topologies are examined as a power conditioner for three phase Photovoltaic (PV) Systems All these topologies are analysed for both continuous and discontinuous modes and extension of the same are simulated through MATLAB/SIMULINK environment Simple boost switching scheme is employed for all these models and the performances of the same are obtained

V. Saravanan

Papers

Reconfigurable solar photovoltaic systems: A review.

Z Source Inverter Topologies-A Survey

Comprehensive analysis of Z source DC/DC converters for DC power supply systems

Novel improved three-level Z-source inverter

Improved Quasi Z Source Inverter topologies for Photovoltaic Systems