Statistical analysis on current harmonics characteristic of photovoltaic generation

Due to the distinguishing features of periodicity, intermittent and fluctuant, the power quality issue of photovoltaic (PV) generation has been a hot topic. PV inverter is the core component of PVplant which determines power quality of the system. Since the output characteristics of PV inverter harmonic currents associated with a variety of factors (inverter topologies, testing conditions, modulation strategy, etc.), the test results of PV plants show randomness to some extent. In this paper, a new analysis method based on distribution fitting is put forward to describe current harmonics of PV generation in detail. The test result is divided into sub-section according to power range and fitted with normal distribution, Weibull distribution and lognormal distribution respectively. Finally, the randomness of power quality assessment on PV plant related to the test environment is analyzed.