Y. McHaouar, A. Abouloifa, I. Lachkar, H. Katir, F. Giri, A. El Aroudi, A. Elallali, C. Taghzaoui,
Volume 18, Issue 1 (March 2022)
Abstract
In this paper, the problem of controlling PWM single-phase AC/DC converters is addressed. The control objectives are twofold: (i) regulating the output voltage to a selected reference value, and (ii) ensuring a unitary power factor by forcing the grid current to be in phase with the grid voltage. To achieve these objectives, the singular perturbation technique is used to prove that the power factor correction can be done in the open-loop system with respect to certain conditions that are not likely to take place in reality. It is also applied to fulfill the control objectives in the closed-loop through a cascade nonlinear controller based on the three-time scale singular perturbation theory. Additionally, this study develops a rigorous and complete formal stability analysis, based on multi-time-scale singular perturbation and averaging theory, to examine the performance of the proposed controller. The theoretical results have been validated by numerical simulation in MATLAB/Simulink/SimPowerSystems environment.
Oorappan G Murugan, Jeevanandham Arumugam, Suresh Velliangiri,
Volume 19, Issue 4 (December 2023)
Abstract
Single Source Cross Connected Reduced Activated Switched-Capacitor Multilevel Inverter (S2C2RASCMLI) accompanied by fewer active switching components is appealing to nine-level of voltage with its simplicity and a solid network. In AC power distribution systems, multi-level inverters are used as DC-to-AC converter operations to achieve the desired output magnitude and frequency. It is employed for the smooth operation of electrical machines. The proposed S2C2RASCMIL cell yields a nine-level voltage with ten switches, nine driver signals, and two flying capacitors for dynamic load operation with reduced active switches. It has the capability of boosting the input voltage double the times. The proposed multilevel inverter operated on nine switching modes and in each mode, three switches have been conducted. It can be extended horizontal and/or vertical structure to produce more levels of output voltages. The hardware prototype was made and the results have been presented. To demonstrate the advantages of the new proposed multilevel inverter topology, a comprehensive comparison with a few other similar multilevel inverter configurations is done. Analysis and simulation output waveforms for a variety of load conditions were tested to check the feasibility of the proposed new multi-level inverter. The proposed MLI offers better performance than existing multilevel inverters.
