Method and apparatus for monitoring maximum power point tracking

摘要

A method and apparatus for monitoring maximum power point tracking (MPPT) by measuring, external to a device that performs the MPPT, a DC current and a DC voltage to obtain a DC current value and a DC voltage value, wherein the DC current and the DC voltage are from a distributed generator (DG) coupled to the device. The method determining, external to the device, a constellation of data points, wherein each data point of the constellation comprises a DC voltage change and a corresponding DC current change resulting from an AC waveform, and determining, a dynamic resistance of the DG based on the constellation. The method computes a ratio of the DC voltage value to the DC current value, compares the dynamic resistance to the ratio, and determines, based on the comparison of the dynamic resistance to the ratio, if the DG is biased at a maximum power point (MPP).