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An adaptive selective current harmonic cancellation (ASCHC) scheme for the permanent magnet brushless dc (PMBLDC) motor drive is presented in this paper. The proposed least mean square (LMS) adaptive filtering algorithm to eliminate selective line current harmonics is one among the methods of adaptive noise canceling in digital signal processing. The harmonic cancellation task is accomplished by generating reference signal with frequency that should be eliminated from the motor line current. The weights of adaptive filter are adjusted to totally eliminate the component with undesired frequency. In consequence, the proposed methodology also reduces the input current total harmonic distortion (THD). The triumph of the algorithm is validated by MATLAB/SIMULINK toolbox for simultaneous elimination of fifth and seventh harmonics in the drive line current. [ABSTRACT FROM AUTHOR]

Permanent magnet brushless dc motor (PMBLDCM) drives are continually gaining popularity in motion control applications. This paper investigates the performance of direct current controlled pulse width modulation (DCC-PWM) based control of four-switch three-phase (FSTP) inverter feeding permanent magnet brushless dc (PMBLDC) motor. A MATLAB/Simulink model for the FSTP fed PMBLDC motor is developed and tested with direct current controlled PWM method. The triumph of the DCC-PWM in obtaining desired speed-torque characteristics is validated with help of simulation results. The DCC-PWM is also implemented with proportionalintegral controller using TMS320LF2407 digital signal processor. [ABSTRACT FROM AUTHOR]

AbstractA numerical study was conducted to explore the effective usability of prismatic triangular channel solar air heaters integrated with longitudinal fins and quadrilateral rib turbulators. Using the matrix inversion technique and MATLAB-developed code, the governing equations of the system were solved. The analytical model is confirmed, showing commendable agreement with an average discrepancy of 4.2%. For the constant value of quadrilateral rib conditions, the first law and the thermohydraulic performance of the novel air heating system are analyzed by considering the design and operating conditions of Reynolds number, fin height ratio, fin thickness ratio, and number of fins. The achieved results reveal that the provision of fins with rectangular rib roughness enhances the thermal and effective thermal performance by optimizing fin design parameters, leading to a maximum value of 85.48% and 78.58%, respectively. The comparison results reveal that the present work improves the effective thermal performance by 5.14% to 20.2% up to the Reynolds number of 21600. It is an attractive design, achieving a rise in temperature parameter up to 0.012 W/m2K. [ABSTRACT FROM AUTHOR]

Aim: Transcatheter mitral valve-in-valve (TMViV) replacement for degenerated surgically implanted bioprosthetic valves has been described by both transseptal and transapical approaches. The balloon-expandable Myval transcatheter valve (Meril Life Sciences, Vapi, India) is commonly used for transcatheter valve-in-valve procedures in India. This study aimed to report in-hospital, 30-day, and 1-year outcomes of Myval patients who underwent TMViV in a single tertiary care centre in India., Methods: Symptomatic patients with surgical bioprosthetic mitral valve failure with New York Heart Association (NYHA) class III-IV symptoms, despite optimal medical therapy and high or very high risk for redo surgery, were assigned to TMViV following heart team discussions. Data were retrospectively collected and outcomes assessed., Results: Twenty patients were treated, with mean age 64.4 years, 60% were female, and mean Society of Thoracic Surgeons (STS) predicted risk of operative mortality score was 8.1. The failure mechanism was combined stenosis and regurgitation in 60% of patients. Technical success was achieved in 100% of patients. The mean postprocedure and 30-day gradients were 4.6±2.7 and 6.3±2.1, respectively. None of them had significant valvular or paravalvular leaks or left ventricular outflow tract obstruction. All-cause mortality at 1 year was 10%, and all survivors were in New York Heart Association (NYHA) class I or II., Conclusion: TMViV replacement with a Meril Myval can be safely performed with high technical success, and low 30-day and 1-year mortality., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)