Effect of Local Shunting on the Electrical Mismatch Losses in Industrial Silicon Photovoltaic Modules

Abstract

The paper presents the results of investigation on the influence of an ohmic shunt located at various spatial positions on the photovoltaic module performance by distributed diode model based simulations. By systematically varying the parameters such as the resistance of the shunt, proximity to the finger and busbar metallization, area of the shunt, irradiance and number of shunted cells in the module, a deep insight about the impact of the shunt on the module electrical performance have been obtained. Further, influence of spatial location of shunts has been studied by assuming a shunted region of same area and severity at different positions in the photovoltaic module, based on the proposed simulation approach. The study revealed novel insights about significance of spatial locations of shunts and the proximity of finger and busbar metallization. In general, it was found that the proximity to the busbar and finger metallization and the shunt position holds the key to the impact the shunt will have on the photovoltaic module performance in addition to the resistance of shunt itself. Quantum of loss due to the presence of finger or busbar metallization in close proximity of shunt location has been revealed by the proposed approach. This understanding can enable to gain an improved performance of the photovoltaic cell and module, by implementing the approach at the cell production level.