Frequency adaptive repetitive control of grid connected inverter for wind turbine applications

This paper is concerned with the current control of grid connected inverters based on a simple frequency adaptive repetitive controller. A grid-tie inverter is desired to behave as a robust current source inverter with the high gain in order to improve both the reference current tracking and disturbance rejection capabilities. The variations of grid impedance and frequency in distribution networks are some important challenges in the design of grid interfaced converters. In this research, the performance of a frequency adaptive repetitive controller (RC), which is based on the internal model principle (IMP), is investigated for a single-phase grid connected inverter.