Facility to measure solar cell ac parameters using an impedance spectroscopy technique

Abstract

An experimental setup has been developed to measure the solar cell ac parameters using an impedance spectroscopy technique. It consists of an electrochemical interface to set the dc bias voltage and to apply the signal voltage across the solar cell and a frequency response analyzer to generate the excitation signal with varying frequency and analyze the result. The setup is calibrated with a standard RC network and measured an error of ±4% (maximum). Solar cell capacitance, parallel resistance and series resistance are calculated from the measured data.

Hybrid Inorganic–Organic Heterojunction Solar Cell

“…This deviation can be attributed to variation of R sh with frequency at high illumination intensity. 29 The lower values of series resistance obtained from impedance spectra than from J-V may be attributed to the disappearance of interface states at high frequencies.…”

“…28 The AC equivalent circuit of a p-n heterojunction solar cell consists of three elements: the series resistance R s (due to bulk and contact resistances), the parallel resistance R sh (due to recombination in the depletion region), and the total capacitance (the sum of the diffusion and depletion capacitances). 29,30 Since the capacitances are in parallel, this equivalent circuit has a single time constant and the plot of Z versus Z¢¢ for a range of frequencies should be a semicircle with a diameter R sh displaced from the origin by R s .…”

Simulation for capacitance correction from Nyquist plot of complex impedance–voltage characteristics

“…At this point, it is convenient to generalize Eq. (17) by introducing the measured capacitance of the p-n junction, C m [7,8] …”

“…Most impedance analyzer and capacitance meters measure the capacitance of the diode under test by applying a constant amplitude AC voltage, and displaying the imaginary component of the resulting AC current [7,8]. Impedance analyzer surmises the device to be represented by the parallel circuits in Fig.…”

Creating dynamic equivalent PV circuit models with impedance spectroscopy for arc fault modeling

“…The dynamic circuits have been developed based on different semiconductor models (e.g., carrier physics [1]), but to determine the values for the circuit components, timedomain [7][8][9][10] or frequency domain techniques [9,[11][12] are used. One dynamic equivalent circuit model and the simplified electrical circuit model are shown in Figure 2 [10][11][12][13], where: This model can be simplified by combining electrical components, as shown in Figure 3. Chenvidhya et al [14] calculated the equivalent complex impedance to be…”