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In this article, a distributed switched control system is proposed, which aims at frequency regulation and total generation cost minimization within a droop-based microgrid considering generator and line power constraints. The minimization is solved with the Lagrange method and is achieved by realizing the equal incremental cost criterion via a consensus algorithm. An online network reconfiguration is also proposed, which bypasses a distributed generator when it violates the generation limits or gets disconnected, or when its corresponding line power flow exceeds its upper limit. It is mathematically probed that the proposed reconfiguration is a distributed online Kron reduction, which leads to a new reduced data network; it preserves the existing spanning trees from cutting when a distributed generator is bypassed. Equilibrium analyses are conducted to show that the proposed switched system converges to the desired steady state. The stability of the system based on common quadratic Lyapunov function is discussed. The effectiveness of the proposed controller for different case studies is verified by adapting it to a test microgrid system. [ABSTRACT FROM AUTHOR]

This paper proposes a secondary voltage, frequency, and active power sharing control for autonomous inverter-based microgrids with event-triggered communications. A proportional-integral consensus-based control scheme is introduced which benefits from need-based (event-triggered) data exchange among distributed generators. The employed event-triggering condition i) ensures the system stability, ii) ensures that the system is Zeno-free and there exists a controllable minimal inter-event time, iii) removes the redundant communications during both transient and steady-state stages, iv) accounts for directed communication network architectures, and v) is fully distributed from both design and implementation standpoints. Effectiveness of the proposed controller for various case studies is verified via MATLAB/Simulink-based simulations. Comparison between different cases and conventional strategies are also included. [ABSTRACT FROM AUTHOR]

This paper proposes a distributed control scheme to compensate for droop-induced frequency deviations in autonomous microgrids. In this scheme, no extra direct frequency control and proportional-integral compensation are employed to remove the frequency deviations; that is, the deviations are compensated instantaneously. To reduce the communication burden, the scheme is then equipped with a need-based (event-triggered) data exchange strategy. An event-triggering mechanism is introduced, which highly reduces the amount of communications in both transient and steady-state stages and ensures that the intervals between consecutive communication instants are positive (i.e., the system is Zeno-free). Stability and equilibrium analyses of the resultant system considering the whole system dynamics are provided, as well. Effectiveness of the proposed controller for different cases is verified by simulating a microgrid in MATLAB/SimPowerSystems software environment. [ABSTRACT FROM AUTHOR]