Impact of power quality disturbances on PV inverters 7#x2014; performance of integrated protective functions

This paper provides a discussion on the implementation of protective functions in photovoltaic (PV) inverters in terms of sensitivity to power quality disturbances. First, sensitivity characteristics obtained from extensive testing on a set of commercial products are presented. The results show that most inverters exhibit a quite sensitive behavior, which can lead to repetitive spurious tripping. Then, a discussion on the implementation of the interface protection (under/over voltage and frequency) is provided. Various methods for voltage and frequency protection are considered, and the impact of the possible implementations are analyzed and quantified. This paper puts forward the thesis that the high sensitivity of current products to power quality disturbances is in fact not due to the lack of efforts put on the development of the equipment but rather to the lack of awareness and clear requirements in standards. Due to this lack of awareness, manufacturers may not make the best choices when implementing the interface protection.