A Novel Distributed Secondary Control Method for Microgrids with Forced Deviation Constraint

Dynamic perturbations and power fluctuations in microgrids are hard to predict, leading to frequency and voltage overshoots beyond allowable limits. Aiming to solve this issue and address stable coordination, this work develops a distributed control scheme with forced deviation constraint capability. In the proposed scheme, an activation function is innovatively applied to the distributed algorithm to project tracking errors from the real number field to the expected range set. The limited control input obtained based on the constrained error can effectively constrain the output frequency and voltage state of the controlled distributed generators (DGs), thus avoiding unexpected fluctuations and overshoots.