Assessment of the Usability and Accuracy of the Simplified One-Diode Models for Photovoltaic Modules

Abstract

Models for photovoltaic (PV) cells and panels, based on the diode equivalent circuit, have been widely used because they are effective tools for system design. Many authors have presented simplified one-diode models whose three or four parameters are calculated using the data extracted from the datasheets issued by PV panel manufactures and adopting some simplifying hypotheses and numerical solving techniques. Sometimes it may be difficult to make a choice among so many models. To help researchers and designers working in the area of photovoltaic systems in selecting the model that is fit for purpose, a criterion for rating both the usability and accuracy of simplified one-diode models is proposed in this paper. The paper minutely describes the adopted hypotheses, analytical procedures and operative steps to calculate the parameters of the most famous simplified one-diode equivalent circuits. To test the achievable accuracy of the models, a comparison between the characteristics of some commercial PV modules issued by PV panel manufacturers and the calculated current-voltage (I-V) curves, at constant solar irradiance and/or cell temperature, is carried out. The study shows that, even if different usability ratings and accuracies are observed, the simplified one-diode models can be considered very effective tools.

A Procedure for Modeling Photovoltaic Arrays under Any Configuration and Shading Conditions

“…The authors are also working on the implementation of the modeling procedure in other languages (such as C and C + +) to improve its versatility. Furthermore, the proposed model can be modified to consider different circuital representations of the PV module, such as the ideal single-diode model [22], the R s model [5], and the two-diode model [26], among others, with the aim of evaluating different PV technologies, accuracy levels, and calculation speeds.…”

“…In this paper, the single diode model (SD) is adopted to represent the PV module operation due to its tradeoff between accuracy and complexity [4,5]. Figure 2 shows the equivalent circuit, including the bypass diode, which must be considered when the modules operate under partial shading conditions.…”

“…Therefore, a PV module can be considered as the basic unit to model the array. The single-diode model is one of the most widely reported and accepted equivalent circuits [4,5] to represent a PV module, because it provides a tradeoff between complexity and accuracy. The parameters of the single-diode circuit can be calculated using procedures as the ones introduced in [4,6]; such procedures take into account the operating conditions (i.e., irradiance and temperature) and the PV modules' datasheet information.…”

Modeling and Stability Analysis of a Single-Phase Two-Stage Grid-Connected Photovoltaic System

“…The output current ipv of the PV array is related to the output voltage upv and also affected by other parameters of PV panel itself [25]. However, the manufacturer's datasheet do not provide some of these parameters, such as equivalent series resistance and equivalent parallel resistance.…”

“…Similarly, the imaginary part of ∂λ i /∂µ is associated with the movement in vertical direction. Table 3 lists the eigenvalue sensitivities with respect to PI controller parameters calculated by (25). For λ 1,2 , the most sensitive parameter is K p3 as the real part of the sensitivity of λ 1,2 with respect to Energies 2017, 10, 2176 9 of 14 K p3 is the largest.…”