A parameter extraction routine for three-diode lumped parameter model of organic solar cells (OSCs) based on particle swarm optimization (PSO) is presented in this letter. In the process of parameter extraction by using PSO, we overcome the problem of encountering locally optimal solutions, where such a problem results from the similar effects of some parameters on I-V characteristics. Combining with the analytical solution algorithm of OSCs’ three-diode lumped parameter model, our parameter extraction routine can efficiently acquire the accurate fitting parameters to complete simulations for I-V characteristics. Furthermore, this routine is valid for the different algorithms of the solution to OSCs’ I-V properties. Finally, we use the experimental data measured from OSCs to verify the parameter extraction routine. As a result, such a parameter extraction routine can perform as an important tool to extract the fitting parameters of OSCs’ lumped parameter model.

A non-iterative method is presented to accurately extract the five parameters of single diode model of solar cells in this paper. This method overcomes the problems of complexity and accuracy by simplifying the calculation process. Key parts of the equation are to be adjusted dynamically so that the desired five parameters can be obtained from the I-V curve. Then, the I-V and P-V characteristic curves of solar cells are used to compare the effectiveness of this method with other methods. Furthermore, the root mean square error analysis shows that this method is more applicable than other methods. Finally, the I-V and P-V characteristics simulated by using the extracted parameters in this method are compared and discussed with the experimental data of solar cells under different conditions. In fact, this extraction process can be regarded as an effective and accurate method to estimate solar cells’ single diode model parameters.

A lumped-parameter equivalent circuit model is proposed to simulate the S-shaped current-voltage (I-V) characteristics exhibited in organic solar cells. First, we derive an explicit terminal current solution as a function of terminal voltage from the equation set of the three-diode lumped-parameter model proposed by Mazhari. Second, we improved Mazhari's model to improve the accuracy and developed the explicit solution of our improved model to improve the efficiency. Third, we use the method of least squares, Newton-Raphson root-finding scheme, and experimental data to validate the solutions of Mazhari's and our models. As a result, owing to high accuracy and efficiency of computation, our explicit calculation scheme, regarded as a useful tool, can help to implement Mazhari's and our models into photovoltaic device and system simulators in compact format.

An explicit current-voltage model for cylindrical surrounding-gate polysilicon (poly-Si) transistors with a doped poly-Si channel is presented. It is based on an intermediate parameter which is derived analytically from the 1-D Poisson's equation and satisfies the corresponding boundary conditions. The surface and midpoint potentials are described as functions of this intermediate parameter. Furthermore, the drain currents in the different operational regions are analytically integrated. Our model results show good agreement with numerical and experimental data. The use of the explicit surface potential solution results in an easy implementation into circuit simulators.