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25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4434-4437, Electrolytic capacitors are a bottleneck for inverter lifetime. Because of the large capacitances used in PV-inverters, a direct replacement by film-capacitors is not feasible for most topologies. This paper presents an active circuit which acts as an interface between the DC-link of a PV-inverter and an additional storage capacitor. By allowing a large voltage ripple at the storage capacitor, the installed capacitance can be used much more efficiently. The proposed method is especially interesting for single-phase single-stage inverters, because here the voltage ripple at the DC-link has to be kept small in order to achieve a good adaption to the maximum power point of the PV-generator.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4289-4293, We compare the outdoor performance of two polycrystalline-Si PV modules of identical design, but with cells based on different types of solar-grade Silicon. The cells of one of the modules are made of Si feedstock purified in the conventional chemical route, whereas the other module has cells based on solar Si produced from a pyrometallurgical route. Electrical and electronic parameters of the modules are extracted from measured currentvoltage data and compared. The two modules perform similarly in the Nordic conditions at which they have been tested. Only minor differences are found between their electrical parameters. Analysis of the electronic parameters related to p-n junction quality reveals the general similarity of the two materials, but also indicate subtle differences.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4475-4478, Partial shading conditions may reduce the energy yield in PV systems due to poor MPPT algorithm or system configuration. The MPPT techniques using scanning approach are capable of tracking the global peak power but it results in loss of energy each time the scan is performed. In this paper we propose a new scanning MPP approach that changes the time-interval between scans adaptively based on the probability of a shift of operating point having occurred.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4688-4691, With increased penetration of PV generation in the power grid, it becomes necessary to control the PV generation similar to the conventional power sources. For small-scale grid-connected PV system, on-site consumption can be matched with the PV generation by either utilizing demand response mechanisms or storage batteries. This paper provides the path efficiency analysis for grid-connected inverter system with storage battery. The proposed energy management scheme is based on the financial profit of cycling the energy through storage battery.

25th European Photovoltaic Solar Energy Conference and Exhibition / 5th World Conference on Photovoltaic Energy Conversion, 6-10 September 2010, Valencia, Spain; 4398-4401, This paper presents a digital control strategy for a PV/battery/Genset hybrid system. The strategy is implemented using power electronics converters and Texas Instruments microcontroller TMS320F28035. The effectiveness of the control strategy for extracting maximum power from the PV, effective battery charging, high reliability, cost effectiveness and minimum CO2 emission of the hybrid is presented.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 3668-3672, The occurrence of multiple local maxima due to partial shading conditions poses a serious challenge to MPPT techniques. This paper compares the popular real-time MPPT algorithm with the scanning approach using PSPICE simulation. The MPPT methods are compared at dynamic partial shading conditions. The compromises between real-time and scanning methods are investigated. It is shown that the scanning approach is able to search for global MPPs but incurs power loss during the scanning period. A new strategy that reduces the scanning period by skipping parts of the voltage range is presented in this paper.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 3277-3279, The purpose of the work is to protect the DC-wiring of PV-systems against safety hazards due to electric arcing. The work analyses possible fault scenarios in the wiring and their meaning for the system safety. Weaknesses of state-of-the-art PV-installations are shown and an approach for an “intelligent” DC-circuit-breaker is presented. Results from an experimental setup are shown.