Operational testing of grid-tied micro inverters

The paper is aimed at micro inverter tests to evaluate the efficiency of maximum power point tracker and stability of operation under variable power network voltage magnitude and frequency. The tests were performed on four micro inverters of different brands. Inverters were connected to low-voltage public distribution system, or to an artificial supply system powered by a synchronous generator simulating the variable voltage magnitude and frequency, subsequently. The paper presents and discusses the achieved results on which a new test protocol related to the grid-tied micro inverters is finally proposed.