Abstract—The inverter is the key element in grid-connected
photovoltaic systems. Measurements of inverter efficiency should
take into account two phenomena: the DC/AC conversion and
Maximum Power Point (MPP) tracking process.
Since the solar energy flux is variable, the PV-inverter operates
with a wide range of load levels and also must face rapid changes
of the input power. For MPP-tracking both static and dynamic
conditions introduce problems that must be solved at the level
of MPPT control algorithm.
The reaction of some inverters to rapid irradiance changes has
already been studied by applying selected input test-patterns in
laboratory conditions. This paper presents the opposite approach
by taking the recorded real-life irradiance profile and simulating
the tracking algorithm behavior.
The results of calculation of dynamic MPP-tracking efficiency
have been performed for basic Perturb&Observe algorithm,
using irradiance data of a variable-cloudy day, recorded with
1 s resolution.
Index Terms—inverter, efficiency, MPP-tracking, dynamic behavior,
photovoltaics.