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Ozone generation is a water disinfection method, superior to chlorine in terms of fewer byproducts and no residual taste. However, its high production cost limits its widespread adoption. This paper designs an ozone generation sinusoidal power supply for water treatment. Ozone generation requires a high-frequency and high-voltage power supply to produce ozone from oxygen molecules. The study evaluates two power supply topologies, one with a parallel LC filter and the other with an LCL filter, assessing their feasibility, effectiveness, and reliability. Theoretically, the LCL filter achieves higher gains than the parallel LC filter. The larger inductance in the parallel LC filter reduces gain, while the larger inductance in the LCL filter increases gain. Simulation and practical results validate these findings, achieving gains of 40 for the parallel LC filter and 150 for the LCL filter. [ABSTRACT FROM AUTHOR]

Background: A commercially significant species in the aquaculture sector globally, particularly in Egypt, is Litopenaeus vannamei. Aim: The experiment's objective was to ascertain how Sanolife PRO-F impacted the growth, water quality, immunological response, and intestinal morphometry of L. vannamei. Methods: In the current investigation, which lasted 12 weeks, Sanolife PRO-F was administered to shrimp post-larvae at diet doses of 0 (control), 1 (group one), 2 (group two), and 3 (group three) g/kg diet, respectively. Each experimental group had three repetitions. Results: In the current study, shrimp fed on probiotic-treated diets showed a considerable improvement in growth performance measures and survival rate, and the nonspecific immune response was also enhanced. Shrimp fed probiotic diets had longer and more intestinal villi overall. Shrimp fed on the G2 and G3 diets showed no appreciable differences in growth or intestinal morphology. With the G2 and G3 diet, the water had lower concentrations of nitrite and ammonia. Conclusion: The study's findings indicate that Sanolife PRO-F treatment at 2–3 g/kg feed promotes the growth of shrimp, immunological response, gut health and function, and water quality. [ABSTRACT FROM AUTHOR]

Adjustable-speed drives based on multiphase motors are of significant interest for safety-critical applications that necessitate wide fault-tolerant capabilities and high system reliability. Although multiphase machines are based on the same conceptual theory as three-phase machines, most undergraduate electrical machines and electric drives courses do not cover this topic. Setting aside the analysis challenges addressed in state-of-the-art literature, undergraduate electrical machines and power electronics courses are a good opportunity for students to understand the main concepts underlying such electric drive systems. This paper presents an adjustable-speed multiphase drive system senior project for electrical engineering undergraduate students that addresses their attainment of the course's learning outcomes. Eight of the course's students were assigned to build the multiphase variable-speed motor drive system. From a pedagogical point of view, this paper describes the methodology of using a senior project to engage students through experiential learning of electric drive systems, which span disciplines such as electrical machines, control, power electronics, and electronics. Students acquire both technical skills and soft skills, which are evaluated through various assessment activities. A number of lessons for future work have been drawn from the experience of applying this project-based learning approach.

This paper studies the performance of screened switched reluctance motors (SRMs) with a number of rotor poles higher than the number of stator poles. Flux (conducting) screens are electrically conducting, non-magnetic materials like aluminum or copper. These screens fill the interpolar rotor air gaps decreasing the unaligned inductance, and thereby increasing the output torque. In addition, flux screens result in a cylindrical rotor structure which minimizes windage losses especially at high speeds. The paper investigates the effect of the flux screens thickness and material on the SRM performance including output torque, power and phase current. A modified flux tube approach for estimating the unaligned inductance of screened SRM is proposed. Finite element analysis results for different screen cases confirm the effectiveness of conducting screens in improving the torque, hence power capability, of switched reluctance motors. [ABSTRACT FROM AUTHOR]

This paper presents a modified adaptive Kalman filter for sensorless current control of a three-phase inverter-based distributed generation system. Measurement and digital signal processor delays have been compensated by using a modified Kalman filter. The control variable states can be estimated one sample in advance with a reduced number of sensors. Two current control loops with the steepest descent adaptive control for grid voltage estimation have been employed to boost robustness. Stability and dynamic performance have been examined for different state variables using root locus. Simulation and experimental results validate the proposed control approach. Index Terms--Adaptive control, distribution generation (DG), grid connected, inverter, Kalman filter.

A new operational mode for diode-clamped multilevel inverters termed quasi two-level operation is proposed. Such operation aims to avoid the imbalance problem of the dc-link capacitors for multilevel inverters with more than three levels and reduces the dc-link capacitance without introducing any significant voltage ripple at the dc-link nodes. The proposed operation can be generalized for any number of levels. The validity of the proposed multilevel inverter operational mode is confirmed by simulations and experiments on a prototype five-level diode-clamped inverter. Index Terms--Multilevel inverter, neutral point clamped.

The three-phase, three-wire, five-level cascaded inverter is used as a medium-voltage shunt active power filter. The capacitor voltage-control technique used as a harmonic current extraction method for the two-level inverter is extended to the five-level shunt active power filter, with a technique proposed for balancing capacitor voltages. Predictive current control based on the supply current (not the active filter current) is employed. Two different space vector modulation (SVM) techniques viz., phase-shifted SVM and hybrid SVM, are used for multilevel inverter pulsewidth-modulation generation. The proposed five-level shunt active power filter is validated by simulation and practically for both modulation techniques. The proposed technique results in the same software and hardware requirements for any m-level inverter. Index Terms--Active filter, multilevel inverter, power quality (PQ).