To certify a grid-tied PV inverter you must prove its maximum-power-point tracking (MPPT) efficiency under realistic, repeatable conditions. EN 50530 defines the static and dynamic MPPT tests; the Sandia profiles are the US equivalent.
How a solar array simulator helps
A PV simulator generates the inverter’s input I-V/P-V curve and sweeps irradiance and temperature, including dynamic ramps and shadow events, so the inverter’s tracker is measured against a known reference.
The N35500 with NS91000 runs EN50530 static and dynamic and Sandia profiles to 2250 V.