An Innovative, Adaptive Faulty Signal Rectifier Along with a Switching Controller for Reliable Primary Control of GC-VSIs in CPS-Based Modernized Microgrids

Abstract

Nowadays, networked controls using cyber-physical systems (CPSs) necessitate engineers considering “faulty signals” into the control from the beginning of the design process. Therefore, synthesizing control methods, which are able to deal with faulty signals and tolerate them, must be thoroughly investigated and integrated into the design process from the commencement. This article proposes an innovative, reliable control based on a sliding mode faulty signal rectifier for active-/reactive-power-controlled, grid-connected voltage-source inverters (named GC-VSIs hereinafter). It is called “faulty-signal-tolerant” control in this article. Those faulty signals can reach the GC-VSI s controls from any sources; for example, they may arise provided that the CPSs malfunction or fail to prevent data-integrity-related issues, cyber threats, and more. The sliding mode algorithm provides the proposed controller with resilient performance via rectifying faulty signals. Besides, the proposed structure is enhanced by an adaptive mechanism, which makes it more robust against the “unknown” nature of faulty signals. The adaptation rule is able to find the unknown bounds of faulty signals (which externally impact control feedback) and incorporate them into the control by the sliding-mode-based faulty signal rectifier to form a faulty-signal-tolerant methodology. Thorough theoretical analyses, including stability assessment using the Lyapunov criterion, are provided in order to design the proposed controller. Comprehensive simulations and experimental results (associated with a GC-VSI) show the effectiveness and reliability of the faulty-signal-tolerant controller, which is proposed in this research.