![]() The magnitude of diffusion capacitance is much larger than the transition capacitance one. The transition capacitance describes the charge stored in the depletion region at the semiconductor p-n junction and the diffusion capacitance describes the charge stored in the neutral region of the semiconductor outside the depletion region. For the dynamic analysis considered here, the equivalent PV cell electric circuit is obtained by replacing the diode with the diffusion capacitance ( C D,PVc), the transition capacitance ( C T,PVc) and the dynamic resistance of diode ( R d,PVc), Figure 7b. For the lightning transient study in this paper, the dynamic PV single-diode model is adopted, as shown in Figure 7a. The single-diode model, double-diode model, and modified three-diode equivalent circuit model, are the most adopted ones to represent the PV cells in circuit simulation under DC conditions. The models of active electrical circuitry for PV cells were extensively studied over the years. Therefore, the 3D model ( Figure 5d) incorporates features such as the geometries of the frame and the traces which connect the PV cells within the module. The relative complement of the internal loop area A dm and the frame loop area A f determines the common-mode area A cm (purple). The conducting frame around the PV module determines a second closed loop, enclosing the frame area A f (green). Since the up–down transitions on different planes of the semiconductor cells do not contribute significantly to the concatenated magnetic flux and, consequently, to induced voltages, we assumed a planar path for the cell interconnections consequently, the connections create a geometric loop (see the equivalent brown line Γ in Figure 5b,c), determining a differential-mode area A dm (grey). Finally, results show that the induced overvoltage are highly dependent both on the grounding of the conducting parts and on the external conditions such as lightning current waveforms and lightning channel (LC) geometry.Īccording to the actual size of the PV module and its spatial distribution, the PV inner wiring complex 3D shape is modelled by connections with a thin-wire structure and developing on a planar path Figure 5b). In such a framework, the influence of the PV operating condition on the resulting electrical stresses is assessed moreover, the relevance or insignificance of some parameters, such as the module insulation or the frame material, is demonstrated. ![]() The whole process involves three major steps, i.e., the magnetic-field computation, the evaluation of both common-mode- and differential-mode-induced voltages across the PV module, and the use of the calculated voltages as input to a lumped equivalent circuit of the PV module connected to the DC/DC converter. ![]() In the present paper we develop an improved model of the PV module that: (a) takes into account high-frequency effects by modelling capacitive and inductive couplings (b) considers the electrical insulation characteristics of the module (c) includes the connection to a DC/DC converter. ![]() Recently, the authors introduced a 3D semi-analytical method to study the electromagnetic transients caused by these strikes in a PV module. Photovoltaic (PV) systems are subject to nearby lightning strikes that can contribute to extremely high induced overvoltage transients. ![]()
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