3-dimensional simulator for concentrator photovoltaic modules using ray-trace and circuit simulator

A 3-dimensinal simulator for concentrator photovoltaic (CPV) modules was developed using ray-trace and circuit simulators. By using this total simulator, we can calculate the operating characteristics of CPV modules composed of optical system and InGaP/InGaAs/Ge triple-junction solar cell. A typical flat Fresnel lens was adopted as a first lens and a homogenizer was adopted as a secondary lens. We used a ray-trace simulator ZEMAX. The generated photocurrent was obtained from ray-trace simulation and spectral response of InGaP/InGaAs/Ge triple-junction solar cell. By using the homogenizer, the uniformity of concentrated light was improved. A 3-dimensional equivalent circuit model for InGaP/InGaAs/Ge triple-junction solar cell can carry out calculations considering the in-plane distribution of the concentrated light. From the results of ray-trace, we could know the intensity distribution of photocurrent in each subcell. By using the ray-trace and circuit simulation, the operating characteristics of CPV modules were calculated totally. It was observed that the FF and cell efficiency could be improved by using the homogenizer. We can use the total simulator for the evaluation and optimization of CPV cells and modules.