New Approach for Stability of Perturbed DC-DC Converters

Hote, Yogesh V.,Choudhury, D. Roy,Gupta, J.R.P. The Korean Institute of Power Electronics 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.1

In this paper, a simple technique is presented for robust stability testing of perturbed DC-DC converters having multi-linear uncertainty structure. This technique provides a necessary and sufficient condition for testing robust stability. It is based on the corollary of Routh criterion and gridding of parameters. The previous work based on parametric control theory using Kharitonov's theorem and Hermite Biehler theorem gives conservative results and only the sufficient condition of stability, whereas the proposed method provides the necessary and sufficient condition for testing robust stability and it is computationally efficient. The superiority of the method is compared with the Edge theorem.

On Robust Stability of the Systems

Yogesh V. Hote,D. Roy Choudhury,J. R. P. Gupta 제어·로봇·시스템학회 2009 International Journal of Control, Automation, and Vol.7 No.3

In this paper, to check robust stability for higher order interval systems a step-by-step procedure is presented using simple conditions, on the basis of Routh criterion. In this, it is pointed out that there is no need to apply Routh criterion to all the four Kharitonov’s polynomials in some class of control system problems, and hence reduces the computational cost. Numerical examples illustrate the procedure.

Kharitonov’s Theorem and Routh Criterion for Stability Margin of Interval Systems

Yogesh V. Hote,J. R. P. Gupta,D. Roy Choudhury 제어·로봇·시스템학회 2010 International Journal of Control, Automation, and Vol.8 No.3

In this paper, it is shown that the gain margin and phase margin of interval system can be determined analytically using Kharitonov’s theorem and V. Krishnamurthi’s corollary on Routh criterion without using graphical and iterative techniques. Further, it is proved that the existing results of Anderson et al. [2] on the stability of low-order interval systems using Kharitonov’s theorem are only applicable for absolute stability of the interval system and it is not applicable for relative stability of the interval systems, i.e., for phase margin. The proposed technique and stability analysis for low-order interval systems are verified with examples.

New Approach for Stability of Perturbed DC-DC Converters

Yogesh V. Hote,D. Roy Choudhury,J. R. P. Gupta 전력전자학회 2009 JOURNAL OF POWER ELECTRONICS Vol.9 No.1

In this paper, a simple technique is presented for robust stability testing of perturbed DC-DC converters having multi-linear uncertainty structure. This technique provides a necessary and sufficient condition for testing robust stability. It is based on the corollary of Routh criterion and gridding of parameters. The previous work based on parametric control theory using Kharitonov’s theorem and Hermite Biehler theorem gives conservative results and only the sufficient condition of stability, whereas the proposed method provides the necessary and sufficient condition for testing robust stability and it is computationally efficient. The superiority of the method is compared with the Edge theorem.

A Simulation Study on Optimal IMC Based PI/PID Controller for Mean Arterial Blood Pressure

Sahaj Saxena,Yogesh V. Hote 대한의용생체공학회 2012 Biomedical Engineering Letters (BMEL) Vol.2 No.4

Purpose Blood pressure of postoperative patient, especially adult cardiac patient, increases due to hypertension which can be lowered by injecting an anti-hypertension vasodilator drug sodium nitroprusside (SNP). Monitor and control of dose of drug infusion on patient is necessary to reduce the blood pressure to a prescribed level, which is an important issue in biomedical engineering drug delivery problems. So, there is a need of advanced control system which improves the health of patient in less time and also reduces clinical expenses. Methods In literature, patient’s response to the infusion of drug (SNP model) is modelled. This model has five parameters that vary from patient to patient depending upon his sensitivity to drug. The main objective of our proposed work is to design a robust controller based on internal model control (IMC) structure that works effectively with different types of patient. Here, IMC based one-degree-of-freedom proportional integral (ODF-PI) and two-degree-of-freedom proportional integral derivative (TDF-PID) controllers are designed by utilizing the optimal value of SNP model gain k. Unlike the conventional PI/PID controllers, IMC based PI/PID controller has only one tuning parameter λ which is tuned on the basis of the maximum sensitivity MS. Results The resulting controllers achieve better robust performance criteria for nominal as well as sensitive and insensitive patients. Conclusions The proposed technique is stable, accurate and applicable to a wide range of physiological variations in patient parameters.

Internal Model Control Based PID Tuning Using First-order Filter

Sahaj Saxena,Yogesh V. Hote 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.1

The selection of filter plays an important role in internal model control (IMC) based controller design. As per the rule, for a minimum-phase delay free plant, IMC based controller is obtained by augmenting a filter. We suggest the use of first-order filter for controller design, which is then parameterized to a conventional PIDcontroller. The proposed scheme brings filter size reduction, closed-loop bandwidth enhancement, and easy formulationof the PID structure. The proposed scheme is applied to some class of linear and nonlinear processes. Further the hardware testing for velocity control of precision modular servo system which contains DC servomotoris carried out through this scheme. Quantitative comparison of servo, regulatory and optimal attributes of the proposedscheme with other popular IMC-PID control techniques depicts sharp reference tracking, good disturbancerejection and minimum integral error performance.

Order Diminution of LTI Systems Using Modified Big Bang Big Crunch Algorithm and Pade Approximation with Fractional Order Controller Design

Shivam Jain,Yogesh V. Hote 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.6

In this paper, a novel approach is proposed for the reduced order modelling of linear time invariant (LTI) systems. The proposed approach is a combination of modified Big bang big crunch (BBBC) optimization algorithm and Pade approximation technique. The beauty of the proposed approach is that the selection of solution space for BBBC algorithm is not entirely random, but structured via the use of Pade approximation approach. Hence, two principal criticisms of soft computing algorithms, i.e., random choice of solution space and larger simulation time are averted in the proposed technique. The proposed technique is substantiated via four different numerical examples from literature and compared with existing model order reduction (MOR) techniques. The concept of controller design is introduced via application of fractional order internal model control technique for load frequency control of power systems. Further, BBBC algorithm is employed to tune a boiler loop in power station. The results convey the efficiency and powerfulness of the proposed technique.

Nonrigid Image Registration using Efficient Similarity Measure and Levenberg-Marquardt Optimization

Vilas H. Gaidhane,Vijander Singh,Yogesh V. Hote 대한의용생체공학회 2012 Biomedical Engineering Letters (BMEL) Vol.2 No.2

Purpose Nonrigid image registration using a cubic B-splines transformation model is well known approach in medical imaging. Although, it is successfully applied to medical image registration applications, it exhibits computational complexity due to the lack of dedicated similarity measure and optimization algorithms. Therefore, the main purpose of this paper is to propose a simple and computationally efficient similarity measure with a suitable optimization algorithm. Methods In this paper, an efficient similarity measure is proposed for automatic nonrigid medical image registration. The proposed approach is based on Gerschgorin circle theorem and covariance matrix properties. In this approach,image registration is carried out by similarity calculation between two normalized images. The proposed similarity measure is optimized using the Levenberg-Marquardt back propagation (LMBP) algorithm. Results Experimental results for various 3-D magnetic resonance data volume and also clinically acquired 4-D CT image datasets are presented in order to show the effectiveness of the proposed approach. It is observed that the proposed approach is sensitive to a small nonrigid deformation field as well as the overlapping. Conclusions The various simulation results demonstrated that the proposed approach can be effective and promising option in complex 3-D medical image registration as well as in various image processing applications.

Effect of Non-Idealities on the Design and Performance of a DC-DC Buck Converter

Garg, Man Mohan,Pathak, Mukesh Kumar,Hote, Yogesh Vijay The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3

In this study, the performance of a direct current (DC)-DC buck converter is analyzed in the presence of non-idealities in passive components and semiconductor devices. The effect of these non-idealities on the various design issues of a DC-DC buck converter is studied. An improved expression for duty cycle is developed to compensate the losses that occur because of the non-idealities. The design equations for inductor and capacitor calculation are modified based on this improved expression. The effect of the variation in capacitor equivalent series resistance (ESR) on output voltage ripple (OVR) is analyzed in detail. It is observed that the value of required capacitance increases with ESR. However, beyond a maximum value of ESR (r_c,max), the capacitor is unable to maintain OVR within a specified limit. The expression of r_c,max is derived in terms of specified OVR and inductor current ripple. Finally, these theoretical studies are validated through MATLAB simulation and experimental results.

A physiology based model of heart rate variability

Wilhelm von Rosenberg,Marc-Oscar Hoting,Danilo P. Mandic 대한의용생체공학회 2019 Biomedical Engineering Letters (BMEL) Vol.9 No.4

Heart rate variability (HRV) is governed by the autonomic nervous system (ANS) and is routinely used to estimate thestate of body and mind. At the same time, recorded HRV features can vary substantially between people. A model for HRVthat (1) correctly simulates observed HRV, (2) reliably functions for multiple scenarios, and (3) can be personalised usinga manageable set of parameters, would be a signifi cant step forward toward understanding individual responses to externalinfl uences, such as physical and physiological stress. Current HRV models attempt to reproduce HRV characteristics bymimicking the statistical properties of measured HRV signals. The model presented here for the simulation of HRV followsa radically diff erent approach, as it is based on an approximation of the physiology behind the triggering of a heart beat andthe biophysics mechanisms of how the triggering process—and thereby the HRV—is governed by the ANS. The model takesinto account the metabolisation rates of neurotransmitters and the change in membrane potential depending on transmitterand ion concentrations. It produces an HRV time series that not only exhibits the features observed in real data, but alsoexplains a reduction of low frequency band-power for physically or psychologically high intensity scenarios. Furthermore,the proposed model enables the personalisation of input parameters to the physiology of diff erent people, a unique featurenot present in existing methods. All these aspects are crucial for the understanding and application of future wearable health.