Browsing by Author "Gonda, J.M."

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A Comprehensive and Pedagogical Treatment of the Origin, Selection, and Manifestations of Proximal Coupling in Magnetic Circuits
(John Wiley and Sons Inc, 2025) Ubaidulla; Gonda, J.M.; Rao, I.R.
Appreciation/understanding of the factors that affect proximal coupling in magnetic circuits and the manifestations of the effect of coupling due to magnetic proximity are of paramount importance in electrical engineering. In this paper and in another companion paper we endeavor dealing with each of the aspects critically and putting them in one place. Mainly three aspects—factors that affect the coefficient of coupling, expressing the coefficient of coupling in terms of the design parameters—thus showing the symmetry of the inductance matrix, and the factors that contribute to the deviation of the voltage/current ratios from turns-ratio is considered, with the introduction of a new factor—a measure of (a)symmetry between the magnetic paths seen by the associated coils. It is also attempted to counter the wide-spread myth that the proximal coupling imperfection is because of the air-medium and to highlight the fact that it can also arise because of and be controlled by providing controlled magnetic shunting between the associated coils—a very useful insight. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.
A Matrix Inversion-Based Algorithm for Economic Scheduling of Power Outputs of Thermal Units in an Electric Power System Without Losses
(Institute of Electrical and Electronics Engineers Inc., 2021) Rao, I.R.; Gonda, J.M.; Surampudi, S.T.
The economic load scheduling of thermal generating units in a power system is aimed at optimally allocating a stipulated load demand from the load dispatch center, among the several generating units in operation, in a power plant, with the objective of minimizing the overall cost of the generation, while satisfying all the equality (load-generation balance) and inequality (limits on the generating units) constraints of the plant. In the power system parlance, this is famously called as the economic load dispatch without losses, and generally considered cost curves for the thermal units are quadratic approximations. There are several algorithms in use, all of them being iterative in nature, like the Î»-iteration technique. This paper presents a matrix formulation of the same problem, that yields a matrix-based non-iterative, direct solution, with a matrix inversion. This technique is elegant and gives quick and accurate results. It is direct for the cases of schedule without violation of limits and requires minimal adjustments for cases of violating the limits. Few examples are considered, to demonstrate the effectiveness of the technique implemented in MATLABÂ® R2019a, and the results are presented. Â© 2021 IEEE.
A novel device to monitor mobilization of fingers during treatment for stiffness of tendons
(2010) Gonda, J.M.; Kamath, A.J.; Venkatesh Prasad, H.N.; Jagannath Kamath, B.
Conceptualization and development of a novel device to monitor mobilization of fingers of a patient suffering from post-traumatic stiffness of the tendons is presented in this paper. Effectiveness of the treatment depends largely on this component of recovery and is unfortunately beyond the scope of continuous vigil by the doctor. The major post-operative procedure is to keep flexing and extending the fingers, either independently or with external support, usually with the other hand. The patient has to do this diligently and hence monitoring this exercise is of concern. The proposed novel idea is a monitoring system which keeps track of the movements of the fingers using linear ratiometric Hall-effect sensors (Allegro-1321) and magnets attached to the fingers. This can provide reliable data to the doctor to ascertain whether the patient is actually doing his part in effecting a speedy recovery for himself, thus improving the overall efficacy of the treatment. Â©2010 IEEE.
A novel vector-locked loop scheme for synchronized extraction of harmonics
(2010) Bhat, R.A.; Gonda, J.M.; Sumam David, S.
The separation of the fundamental from a distorted waveform is an important component in the implementation of a custom power device. A novel scheme for a vector-locked loop (VLL) for synchronous extraction of harmonics/fundamental in a distorted periodic waveform is described here. An intuitive, though approximate, explanation is provided for the operation of the algorithm, focusing on the locking process and the filtering capability. Performance aspects are analysed and an approximate linear time-invariant model is presented to facilitate in the design. Moreover, a means for choosing design parameters to achieve the optimum performance is provided. Main features of the proposed VLL are its simplicity, excellent insensitivity to harmonics, noise rejection, availability of both fundamental and harmonics without additional processing, and the speed of operation. The claims are verified through extensive simulation studies in MATLABÂ®/SimulinkÂ®. Â© 2010 IEEE.
Investigation into facial expression recognition methods: a review
(Institute of Advanced Engineering and Science, 2023) Devarapalli, A.; Gonda, J.M.
Facial expression recognition (FER) is a rapidly emerging topic in computer vision that has gotten a lot of interest because of its numerous applications in fields including psychology, sociology, human-computer interaction (HCI), and security. FER seeks to recognise and analyse human facial expressions in order to determine emotions and other mental states. Several strategies, including feature-based, kernel-based, and deep learning-based methods, have been developed and implemented in FER in recent years. FER's major goal is to extract and identify the most discriminating elements that accurately represent the emotions expressed by facial expressions. The literature reviewed in this field shows that deep learning-based methods have outperformed traditional feature-based and kernel-based methods in terms of accuracy and robustness in recognizing facial expressions. However, these deep learning-based methods also pose several challenges, such as the need for large labeled-data-sets, robustness to different facial poses and illumination conditions, and generalization to unseen data. Despite these challenges, the field of FER is expected to continue growing, and future research will likely focus on addressing these challenges and improving the accuracy and robustness of FER systems. © 2023 Institute of Advanced Engineering and Science. All rights reserved.
Matrix Formulated Î»-Iteration Method for Economic Load Scheduling With B-Coefficients
(Institute of Electrical and Electronics Engineers Inc., 2022) Rao, I.R.; Gonda, J.M.; Surampudi, S.T.
The load-sharing real power among several generating units in operation across the entire power system mainly depends upon the overall operating cost. Thus there is a need to develop techniques to allocate the scheduled power to generating units to minimize the cost of generation while satisfying both equality (generation-load-loss balance) and inequality (limits on generations) constraints. In this work matrix formulated lambda- iteration method is proposed, where the functions or equations, that are required to solve the economic load scheduling problem are transformed into matrices. Transmission line losses are approximated using Kron's loss formula using B-Loss coefficients. This technique gives quick and nearly perfect (very less tolerance from load demand) results. As a case study, a 6 generators and a 15 generators systems data is chosen to obtain solution to the economic load scheduling problem using matrix formulated lambda- Iteration method. This technique is implemented in MATLABÂ® R2019a and the results are presented. Â© 2022 IEEE.
A novel device to monitor mobilization of fingers during treatment for stiffness of tendons
(2010) Gonda, J.M.; Kamath, A.J.; Venkatesh, Prasad, H.N.; Jagannath, Kamath, B.
Conceptualization and development of a novel device to monitor mobilization of fingers of a patient suffering from post-traumatic stiffness of the tendons is presented in this paper. Effectiveness of the treatment depends largely on this component of recovery and is unfortunately beyond the scope of continuous vigil by the doctor. The major post-operative procedure is to keep flexing and extending the fingers, either independently or with external support, usually with the other hand. The patient has to do this diligently and hence monitoring this exercise is of concern. The proposed novel idea is a monitoring system which keeps track of the movements of the fingers using linear ratiometric Hall-effect sensors (Allegro-1321) and magnets attached to the fingers. This can provide reliable data to the doctor to ascertain whether the patient is actually doing his part in effecting a speedy recovery for himself, thus improving the overall efficacy of the treatment. �2010 IEEE.
A novel vector-locked loop scheme for synchronized extraction of harmonics
(2010) Bhat, R.A.; Gonda, J.M.; Sumam, David S.
The separation of the fundamental from a distorted waveform is an important component in the implementation of a custom power device. A novel scheme for a vector-locked loop (VLL) for synchronous extraction of harmonics/fundamental in a distorted periodic waveform is described here. An intuitive, though approximate, explanation is provided for the operation of the algorithm, focusing on the locking process and the filtering capability. Performance aspects are analysed and an approximate linear time-invariant model is presented to facilitate in the design. Moreover, a means for choosing design parameters to achieve the optimum performance is provided. Main features of the proposed VLL are its simplicity, excellent insensitivity to harmonics, noise rejection, availability of both fundamental and harmonics without additional processing, and the speed of operation. The claims are verified through extensive simulation studies in MATLAB�/Simulink�. � 2010 IEEE.
Performance analysis of compensation current extraction techniques for 3Î¦, 3-wire shunt active power filter under unbalanced supply
(2009) Gonda, J.M.; Anantha Adithya, V.; Sumam David, S.
Actve power filters are effective in mitgating line current harmonics and compensating for the reactive power in the line. Many papers comparing the performance of active power filter extraction algorithms are found in the literature, but there is explicit mention about the suitability of any particular extraction algorithm under all conditions. Hence this paper is an attempt to compare the performance of direct methods of compensating current extraction algorithms for three-phase active power filters under different conditions of mains supply using Matlab/Simulinkâ„¢. Both transient and steady state conditions are considered. The compensating techniques under analysis are: synchronous detection method, sychronous reference frame method, id-iq method, instantaneous active reactive power theory (p-q theory) modied p-q theory, adaptive noise cancellation, notch filtering and Fourier based sinusoidal subtraction algorithms. Under balanced conditions all the compensatng techniques give proper result, but under balanced conditions only few of the compensating techniques work satisfactorily. In fact the equal resistance synchronous detection method and Fourier based sinusoidal subtraction algorithms perform better under extreme conditions. With proper implementation, sinusoidal subtraction algorithm performs better under both transient and steady state conditions. Â© 2009 IEEE.
Real-time implementation of a novel vector-locked loop for synchronous extraction of harmonics in power systems
(2012) Gonda, J.M.; Sumam David, S.
The extraction of the harmonics and or the fundamental from a distorted waveform is an important process in the implementation of custom power devices. Several schemes have been proposed in the past towards this. In this paper the principle of operation, performance, and design aspects of a novel scheme of a vector-locked loop (VLL) for synchronous extraction of the harmonics and or the fundamental from a distorted periodic waveform is briefly described and real-time hardware emulation results are presented. Main features of the VLL are: simplicity, excellent insensitivity to harmonics, noise rejection, availability of both fundamental and harmonics without additional processing, and the good speed of operation. Some results from the real-time hardware emulation of the scheme on a dSPACE-Modular system are presented and compared with the results from MATLAB®/Simulink®.
Real-time implementation of an amplitude-locked loop: A validation on the dSPACE DS1006-based platform
(2013) Gonda, J.M.; Sumam David, S.
The extraction of harmonics and/or the fundamental from a distorted waveform is an important process in the implementation of custom-power devices. Several schemes towards this have been proposed in the past. Among these, the algorithms based on synchronous (with respect to the supply voltages) extraction (both in phase and amplitude) have certain established advantages over the others. Amplitude-locked loops (ALLs) have been in use in signal-communication systems but are limited to sinusoidal inputs. There is a need for fast and rugged algorithms to synchronously extract harmonics and/or the fundamental from a distorted waveform in many power system applications. In this paper a real-time implementation of a novel scheme, which is based on an adaptation of an ALL, is presented for synchronous extraction of harmonics and/or the fundamental from a distorted periodic waveform. The operation of the algorithm, its performance, and its design aspects are briey discussed. The main features of this ALL are simplicity, speed of operation, noise rejection, availability of both fundamental and harmonics without much additional processing, and excellent insensitivity to distortion (robustness). Furthermore, it is applicable to single-phase or 3-phase systems. This paper reports a real-time hardware implementation of the algorithm, thereby validating it. The algorithm is implemented on a real-time hardware-emulation platform, a dSPACE modular system (configured around the DS1006 processor board). It is tested for various cases of interest and the results are presented. © Tübi?tak;.