Resilient cooperative control of AC microgrids considering relative state‐dependent noises and communication time‐delays

Abstract

In this study, a resilient distributed control algorithm is proposed for the secondary voltage and frequency restoration of an autonomous inverter-based microgrid considering simultaneous relative state-dependent noises and communication timedelays (CTDs). The proposed algorithm is robust against potential time-varying stochastic noises and CTDs, which corrupt the data exchanges in the secondary control layer. Additionally, this study considers the contribution of both distributed generation and distributed energy storage (DES) units in islanded AC microgrids. The presence of DES creates the need for an extra control algorithm to provide state-of-charge (SoC) balancing for these units and having precise active power-sharing. The theoretical concepts of the proposed control algorithm, including the mathematical modelling of microgrid, basic lemma, and controller design procedure, are outlined. The performance assessment of the presented control algorithm is evaluated through simulations on a test microgrid in MATLAB/Simulink software. Then, some previously-reported algorithms are selected to compare the proposed control algorithm with them. The obtained results show the effectiveness and robustness of the presented algorithm in regulating the voltage and frequency, matching SoCs, and as a result, having precise active powersharing. P ji uncertain and delayed active-power measured by the ith unit SoC ji uncertain and delayed SoC measured by the ith unit

Distributed LMI‐based control of heterogeneous microgrids considering fixed time‐delays and switching topologies

“…Therefore, the matrix inequalities (24) and (25) can be transformed into the following inequalities:…”

“…In the field of DC MGs, the consensus in voltage and current in the presence of time‐delay are investigated in [22, 23]. In AC MGs, the time‐delay has been discussed with different approaches for both secondary [24, 25]. One of the popular approaches to control delay in a multi‐agent system is the generalised Nyquist method.…”

Resilient distributed control of BESSs and voltage source converter‐based microgrids considering switching topologies and non‐uniform time‐varying delays

“…In order to estimate the SoC of BESSs, the coulomb counting rule will help. The simplified coulomb rule can be expressed as Due to the SoC estimation of the BESSs in the MG, we neglect the power loss of the interfacing voltage source converter (VSC) and assume that the output voltages of the batteries are the same as [15, 20, 22]. Regarding the conservation of energy in the output and input of the VSC, there exists an approximation for each BESS ( ), and the efficiency factor is supposed to be unit ( ).…”

“…Multi‐agent system (MAS) has drawn abundant consideration from various backgrounds in control theory such as containment control for high‐order heterogeneous system [8], Lagrangian delayed system [9], and containment control for linear heterogeneous system with fixed delay [10]. Distributed control based on MAS has been extensively examined for the secondary layer of MGs, for example, robust extended state‐observable‐based control [11], robust disturbance resilient [12], fault‐tolerant control [13], cyber attacks [14], noise resiliency [15], model predictive control [16], and dynamic weights [17].…”

“…In the MG, the communication delays will lead to the time‐synchronisation‐loss of network information, which may demote the synchronisation performance and even decrease the MG system's stability and reliability. To be more precise, communication delays are referred to the amount of time for data to be delivered from the sender to the receiver through a communication channel [15, 18]. The communication time‐delays consist of four components.…”