A photovoltaic panel emulator using a buck-boost DC/DC converter and a low cost micro-controller

In order to facilitate the design and testing of photovoltaic (PV) power systems, a PV emulator which models the electrical characteristic of a PV panel or array is needed. Among different approaches to modeling PV characteristic, namely the I–V curve, curve-fitting is a popular approach. Even though a single high-order polynomial equation may accurately represent the I–V curve, the process of derivation and implementation is rather complex. This paper hence proposes the use of piecewise linear approach which is easier to derive and implement in a low-cost micro-controller. A two-switch buck-boost DC/DC converter is selected as the PV emulator and is analyzed. Experimental results on a hardware prototype of the proposed PV emulator are reported to show the effectiveness of the approach.

► We emulate a photovoltaic (PV) panel using a two-switch buck-boost converter.
► We use piecewise linear approach (maximum 5 lines) to model a commercial PV panel.
► We are able to model the panel’s I–V curves using a low-cost micro-controller.
► Experimental results of a hardware prototype show acceptable accuracy of panel emulation.