DOI: https://doi.org/10.31258/Jamt.5.2
Published: Aug 12, 2024
Articles
Exploring The Potentials and Drawbacks of Hysteresis Current Controller For SRM: A Case Study Of Wind Energy Conversion System
Switched Reluctance Machines (SRMs) have drawn interest in renewable energy systems because of their special qualities and applicability. This study examines the idea of hysteresis current regulation in a wind energy conversion system with a Switched Reluctance Generator (SRG). The system is modeled in MATLAB/SIMULINK. The model is simulated and analyzed to ascertain the system’s benefits and shortcomings, focusing on reducing torque ripples in SRG. Considering most classical controllers are complicated to construct, the hysteresis current control is straightforward and effective. However, this controller's two primary shortcomings are that it produces a variable switching frequency and increases current ripples at a steady state, both enhancing acoustic noise in SRM. Lastly, the report suggests that improving controller performance should be the primary emphasis of future research in this field.

Removal of Microplastics and Performance of a Developed Ceramic Filter
The consumption of microplastics can have harmful effects. To effectively remove microplastics from water using an affordable device, this study developed a ceramic filter based on clay and waste glass. The research evaluated the addition of a porogenic agent and the effects of firing temperature. In the formulations, clay was substituted by a porogenic agent with 10 and 20 by weight, maintaining 10 by weight of waste glass. Ceramic filters were produced by molding press, and evaluated for their physical properties. Its performance was assessed by water permeability at different pressures, leaching of elements, and removal of microplastics. As a result, formulations with a higher porogenic agent content and lower firing temperature present superior permeability, however, permeability increases after higher pressure tests, when structure fracture may occur. Moreover, the formulation with the lowest porosity (without adding a porogenic agent) achieved an impressive removal rate of nearly 99.8%. It was concluded that a ceramic filter could retain microplastics well, as long as the filtration pressure and porosity were optimized to obtain the best results – higher filtration without fracture.

Failure Evaluation of Thermal Spray Coating Using High-Velocity Oxy-Fuel (HVOF) on Steam Turbine Shaft 940-PT 2 A/B
The repair of worn steel shaft surfaces in power transmission systems is made possible by thermal spray procedures, which have become an essential technology in many sectors. With this novel approach, worn shaft components may be recycled effectively since an API 687-compliant wear-resistant coating designed for specialty rotating equipment repairs is applied. The process's efficacy stems from its capacity to extend the functional life of essential mechanical components, therefore decreasing replacement expenses and downtime. The variety of factors that affect the result highlights the intricacy of thermal spray techniques. Finding the ideal mix of these crucial process variables becomes essential to provide the required degree of wear resistance. The coated shafts perform better as a result of this careful tuning, which also guarantees dependability under challenging working conditions. The coated shafts' surface hardness data in this investigation showed that the initial coating hardness value was below the predetermined goals. Several parts that interact with the shaft were redesigned strategically in response to these discoveries. These adjustments were mainly motivated by economic considerations, to optimize effectiveness while resolving the noted hardness deficiencies. Furthermore, a thorough analysis of failure data showed important correlations between different operational parameters and how they interacted, offering a further understanding of how these factors affected wear resistance. This research allowed for the identification of crucial parameters that required change and emphasized the precise balance essential for optimum thermal spray application. All things considered, this study emphasizes how critical it is to use a methodical approach to improve thermal spray processes, guarantee successful shaft component restoration, and ultimately increase the operational longevity of such components in challenging applications.
