Analysis and Design of Fast-Transient Strategy Based on Modified Fast Repetitive Control for Shunt Active Power Filter

In this paper, a modified fast repetitive control strategy is proposed, to shorten the inherent time-delay and storage space of the traditional repetitive control. The design method of an attenuation function of modified m multiple fast repetitive control and its internal model were adopted, and this design can make all the control frequencies be maintained, meanwhile, it adds a feedforward channel, so that between the two resonant peaks, an inverse resonant peak is added to reduce the interference. And the designed method allows the system to achieve a fast dynamic response, and the program occupies minimal storage space. A proportional-integral(PI) regulator is also added to the current control loop, to ensure system stability under severe harmonic distortion conditions. Dynamic and steady state performance of the proposed controller have been compared with the traditional repetitive control. The excellent performances of the control strategy are verified by simulation and experiment results.