PV Cell System Research Articles

Development of a smart photovoltaic cells system

The energy management process in conventional PV systems is performed either in arrays of PV panels or in individual groups of solar cells, resulting in a significant reduction of their energy production due to partial shading, solar cell mismatching etc. In contrast to the existing conventional technology of PV systems, the development of a Smart PV cells system is proposed in this paper, each comprising a conventional solar cell that is connected to an integrated circuit (IC) that has also been developed within the framework of this paper. The IC of the proposed Smart PV cells performs the maximization and management of the energy produced by the solar cells and the communication with a remote operator through the power lines, in order to control and monitor the Smart PV cell operation and enable the detection and localization of solar cell malfunctions. The proposed IC can be combined with any manufacturing technology of solar cells (e.g., multi-crystalline, thin-film etc.). A fully-functional prototype PV system of the proposed Smart PV cells has been designed and constructed. Experimental results are presented in this paper demonstrating the operation and energy production improvement achieved by the proposed Smart PV cell systems.

Conversion efficiency gain for concentrated triple-junction solar cell system through thermal management

Abstract The application of the thermoelectric (TE) modules can provide extra power in PV cell systems, but the increased thermal resistance leads to an increase in the temperature of the PV cells. In this paper, the phase change materials (PCMs) attached to the back side of the PV cell is used to control the temperature of the PV cells. The PCMs transfers the heat absorbed from the PV cell to the TE modules. A comprehensive experimental study is carried out to investigate the performance of the photovoltaic-thermoelectric hybrid system with PCMs. The outdoor tests are performed to reveal the influence of the cooling methods, the sunlight intensity, and the uniformity of the concentrated light spot on the conversion efficiency of the system. The results indicate that the conversion efficiency of the PV-TE hybrid system with PCMs is 0.56% more than solo PV cell system due to a decrease of the PV cell temperature and the efficiency contribution of the TE modules. This work investigates the factors that affect the full spectrum utilization of solar energy in PV cell systems.

Alternative Model of a Subwavelength Diffractive Lens Proposed for PV Cells Applications

Recently, several approaches have been proposed to concentrate and to separate spectrum bands of sunlight using a planar design. Fresnel lenses are widely used in concentrating photovoltaic systems, to achieve the concentration of sunlight onto the surface of solar cells. A diffractive lens superimposed with a grating, in a single integrated optical device, has been proposed to obtain the sunlight spectrum splitting and beam concentration (SSBC) simultaneously. Here, we present an alternative approach to achieve SSBC functionality using only a diffractive lens. Because of the subwavelength structures used, a high efficiency for a broadband light spectrum is demonstrated through simulations. We propose a theoretical model for a subwavelength diffractive lens (SWDL), which has been elaborated with optimal parameters. The model proposed is suitable to be used for low concentration (1– $10\times $ ) PV cell systems. The optical efficiency obtained is $\sim 70$ % after separating apart of the sunlight spectrum (400–1100) nm into two bands (400–800) and (800–1100) nm. A new electromagnetic modeling tool based on a hybrid finite difference time domain angular spectrum method propagator has been used to analyze the performance of the proposed model. The proposed SWDL achieves the functionality of an SSBC over a small distance and can be integrated into a compact PV cells system.