Articles
Publication Date: 2025
IET Power Electronics (17554543)18(1)
This paper presents a novel high-performance and dependable step-up multi-level inverter topology designed specifically for photovoltaic applications. A gain factor of nine is attained, coupled with automatic self-voltage balancing of capacitors and the intrinsic capability to generate both positive and negative voltage levels. All power switches withstand voltages lower than the peak of the output voltage. The quantity of power switches, DC input sources, and the blocking voltage on the switches are reduced. Also, the proposed inverter demonstrates a minimal cost function in comparison to similar topologies. The performance of the 19-level step-up inverter has been confirmed through simulation as well as laboratory results obtained from a constructed prototype. © 2025 The Author(s). IET Power Electronics published by John Wiley & Sons Ltd on behalf of The Institution of Engineering and Technology.
Publication Date: 2025
Chemical Engineering Communications (00986445)212(8)pp. 1233-1242
In this article, a robust control algorithm is proposed for a nonlinear and time-varying continuous stirred tank reactor (CSTR) with sediment formation in the cooling jacket. The existing control schemes may fail, as deposition measurement or estimation is a challenge in such a process. As a main contribution, the deposition phenomenon is modeled here as the system uncertainty. Then, an identification-based robust integral controller is constructed for the underlying CSTR. Applying the loop-shaping procedure here is also a novelty to satisfy the performance objectives in the frequency domain. In a comprehensive scenario, which includes the set-point tracking in the presence of system uncertainties and external disturbance, the performance of the proposed robust control system is evaluated and discussed from a comparison viewpoint. The numerical study shows that fouling control and robust performance are ensured by the developed H∞-based technique. © 2025 Taylor & Francis Group, LLC.
Publication Date: 2025
IEEE Access (21693536)13pp. 207808-207816
This study introduces an innovative disturbance observer to tackle external disturbances and model uncertainties, along with a control strategy based on Lyapunov functions, ensuring global asymptotic stability for a single-phase multilevel inverter for UPS applications. The stability analysis of the proposed method is presented, based on two theorems. The first Theorem guarantees presents a disturbance observer, provides a bounded estimation error for the unknown disturbance, in the single-phase UPS inverter (UPSI). The bounded estimation is then used in designing an observer-based robust controller in the second Theorem, which ensures the convergence of tracking error to a small neighborhood of the origin. The numerical and practical results indicate that the developed control scheme ensures global stability and leads to the desired sinusoidal voltage with an almost low THD. Meanwhile, almost zero steady-state error in the output voltage (OV), and robust dynamic performance under uncertainties and disturbances are attained. © 2013 IEEE.
