  This paper deals with the problem of identification of photovoltaic arrays'
maximum power extraction point---information that is encrypted in the
current-voltage characteristic equation. We propose a new parameterisation of
the classical five parameter model of this function that, combined with the
recently introduced identification technique of dynamic regressor extension and
mixing, ensures a fast and accurate estimation of all unknown parameters. A
concavity property of the current-voltage characteristic equation is then
exploited to directly identify the desired voltage operating point. Realistic
numerical examples via computer simulations are presented to assess the
performance of the proposed approach.
