Method and arrangement for estimating power variations in photovoltaic systems

摘要

Method and arrangement of estimating the power variation in response to change of voltage reference in a maximum power point tracker of a photovoltaic system. The method comprising sampling the power produced by the photovoltaic system with a fixed number of voltages, out of which voltages some are the same and some are different by an amount of a given increment, with the restriction that the average of these voltages produce a net change with respect to the starting voltage in the direction of the increment calculated during previous estimation of the power variation, and estimating the power variation between the first and the last sample using the obtained power samples in which estimated power variation the change of power due to changed environmental conditions is removed.