Photovoltaic (PV) interfaced converters can become unstable and fail due to the nonlinear behavior of the PV source. Key to this problem is the variability of the PV source static and–more importantly–dynamic resistance, challenging the converter control. While recent studies deal with controller design to mitigate this instability, the literature lacks a perspective on the impact of the PV source model, which must be decided when testing a converter in the lab. The single-diode five-parameter PV model is often adopted, however solving its implicit I–V equations requires sound PV modeling expertise. To address this gap, this paper proposes to adopt the PV model from the EN50530 standard to emulate the PV source, and derives a new direct expression for its dynamic resistance. The proposed expression accurately predicts the converter instability when the PV source is operated in its constant current region (CCR), effectively validating the EN50530 PV model for use in PV voltage stability assessments. Experimental hardware results using an industry-grade solar array emulator are performed to test the PVvoltage stability of a 1kW grid-connected inverter. The results compare the converter control performance when the PV source is emulated using the single-diode five-parameter model and the PV model from EN50530.
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