Uniformity characteristic and calibration of simple low cost compact halogen solar simulator for indoor experiments

Abstract

The aim of this article is to discuss in detail, the development of a simple low cost halogen compact solar simulator, including characteristics and calibration. This compact type simulator is expected to be easy to use, set up and move around. We used tungsten halogen incandescent lamps because they are accessible, cheap and work steadily with simple power supply. It is also quick and easy to construct with simple equipment. The construction of the simulator consists of two main parts; the collector module and halogen light sources. The unit dimensions are 430 mm × 390 mm × 1000 mm, and made with an aluminum frame. The collector module faces downwards to the light source, which was placed at the bottom. This method aimed to reduce the interference of light entering from the outside and is captured by the surface of the collector. The result shows that the maximum relative intensity reflects to the center and become non-uniform when shifting to the edge. The optimal distance between the light surface simulator and the test plane was 32 cm, giving the maximum non-uniformity of 9.7%, which is still within the limits allowed by British Standards for solar simulator testing. For non-uniformity limit requirement ≤5%, then the test field covered is 0.54 of the simulator area. Due to the high heat emitted by the halogen bulbs, the PV power output decreased with a gradient of ΔPpv/ΔTpv≈−0.36%/°C as well as the PV efficiency also decreases Δηpv/ΔTpv≈−0.076%/°C. Although the PV output of the simulator and the sunlight with the filter differ, the PV output behavior of the simulator is similar to filtered sunlight. From the filter and outdoor calibration test, indicating that experiments with the simulator can correlate to experiments using sunlight. The ratio of indoor to outdoor measurement results is close to 50%. The current simulator is used as an approximation of solar test performance which contributes to determine the proper design parameters, for further improvement and flexibility applications.