Real-Time Parameter Estimation for PV Modules using a Polymer Dispersed Liquid Crystal Active Shading Screen

Abstract

We present a real-time parameter estimation method to extract cell-level parameters based on a one-diode model formulation during active shading. Active shading is accomplished by a custom fabricated Polymer Dispersed Liquid Crystal (PDLC) screen controlled via relays and precicely timed to work in conjunction with a curve tracer and data acquisition system. Parameters are rapidly extracted and can be used to infer cell degradation and propensity to hot-spot generation. The parameter estimation method leverages an efficient initialization scheme using the Lambert-W function and asymptotic methods. Simulation and preliminary experimental results are provided.