This paper is focused on the dynamic modelling of the polycrystalline silicon wafer-based photovoltaic cells under various operational and fault conditions. The models are drawn from the impedance changes observed using electrochemical impedance spectroscopy. In this paper, tests were carried out at different voltage bias levels under illumination, dark, uniform partial shading, and cell-mismatch conditions. The cell model parameters are extracted from the obtained Nyquist plots and fitted to appropriate equivalent circuits. Results obtained show that, the variations of the AC model parameters can be used for in-line characterization and real-time condition monitoring of the photovoltaic cells/arrays under the different operational and fault conditions.