Modelling of solar cells and modules using piecewise linear parallel branches

This study proposes a novel equivalent circuit model for solar cells and modules. The proposed model approximates the non-linear I-V characteristic of a photovoltaic cell or module by a number of linear circuit branches connected in parallel. The number of these linear circuit branches is adjustable according to the required accuracy. An algorithm based on an equal-area criterion for determining the parameters of the equivalent circuit is also proposed. This algorithm, if incorporated into the software that simulates the proposed model, allows variations of solar irradiance and cell temperature to be taken into account during the simulation. Two numerical examples simulated by electromagnetic transient programme software are presented to demonstrate the performance of the model.