Impact of Latency and Packet Error on Communication in Centralized Microgrid Control: Modeling and Guidelines

This paper proposes a novel dynamic model in the Laplace domain for an advanced ac microgrid with centralized secondary control. The model applies a centralized power-based control strategy and incorporates communication non-idealities such as latency and packet error. Packet loss and communication failure are considered herein as latency issues. The central controller incorporates an anti-aliasing filter that constrains the frequency of the transmitted signal and the packet transmission rate in compliance with Nyquist’s sampling theorem. The model is validated on a test bench, with experimental implementation of the communication system and central controller, and a real-time simulation of the electrical power system via hardware-in-the-loop. The impact of latency on the controller’s performance is evaluated through stability, control bandwidth, load rejection bandwidth, settling time, and rejection of packet errors. The results show that communication latency directly impacts the controller’s performance, affecting all analyzed performance metrics. Meanwhile, the cutoff frequency of anti-aliasing filter and packet transmission rate influence control stability, response dynamics, and the system ability to reject load variations and packet errors. Finally, the paper proposes a flowchart-based guideline for configuring the microgrid central controller and selecting communication technologies to implement ancillary services with predefined durations in advanced microgrids.