Small-Signal Modeling and Analysis of Delayed Microgrids under Distributed Control

The distributed secondary control normally relies on the communication network to exchange information, yet non-negligible communication delays are thus introduced at the same time. Under the influence of communication delays, the well-designed distributed secondary controllers will have poor performance or even failed, making it difficult to meet the requirements for safe and stable operation of microgrids. To study the delay-related stability problem, a delay-concerned small-signal dynamic model of a microgrid under distributed control is developed. On the basis of this model, low-frequency eigenvalue spectrums of the microgrid system are calculated and a delay-related stability analysis is performed. Time-domain simulations are presented to verify the effectiveness of the proposed method.