A distributed secondary voltage and frequency controller considering packet dropouts and communication delay

In this paper, the consensus problem is developed for AC Microgrids (MGs) considering communication delay and packet dropouts. The existing control schemes commonly design the secondary control layer assuming ideal communication channels between distributed generation (DG) units. However, in practical situations, the communication links are exposed to packet dropout and delays which can drastically decrease the quality and stability of DGs controllers. Most of the existing literature studies the impact of delay or packet dropout, and the simultaneous effects of both delay and packet dropout in the communication links considering the rigorous stability analysis and statistical properties are proposed in this paper. Therefore, we propose a new distributed control approach to restore the voltage and frequency to the reference values using the collected sample-based technique of each DG unit. In addition, sufficient consensusability conditions are found when the communication network topology, the DG dynamics, the packet dropout rates, and the communication delay are taken into account. The consensus error of the proposed control strategy is determined, and its convergence is shown. Finally, the proposed method is simulated for different scenarios in MATLAB/SimPowerSystems environment to prove the effectiveness of the proposed secondary control scheme.