Indian Institute of Technology Palakkad&nbsp;(IIT Palakkad or IIT PKD) is a public autonomous&nbsp;engineering&nbsp;and&nbsp;research&nbsp;institute located in&nbsp;Palakkad,&nbsp;Kerala. It was&nbsp;one of the five new&nbsp;IITs&nbsp;proposed in the&nbsp;2014 Union budget of India. The campus was inaugurated on 3 August 2015. The institute has 94 faculty, 978 students, and 63 non-teaching staffs.

IT Palakkad currently offers four-year Bachelor of Technology (B.Tech) and two years MS programmes in 8 different engineering disciplines including&nbsp;Computer Science, Electrical, Mechanical, Civil among others.

&nbsp;

IIT Palakkad

Commercial buildings consume significant portion of electricity in developed countries and air conditioning systems account for bulk demand within the buildings. These air conditioning systems handle large volumes of air and can be utilized effectively as thermal energy storage. This work is focussed on providing Demand Response (DR) ancillary service by adjusting electricity demand from air conditioning system according to grid requirements, considering occupant preferences for additional revenue. First, detailed component-wise mathematical model is developed for the air conditioning system. Subsequently, a transactive market based control algorithm including agent bidding strategies, and market clearing approach is proposed. The proposed control is designed considering the general requirements of the Energy Market Authority (EMA) Singapore's DR programme. Simulation studies are carried out and results show that proposed transactive control is effective in normal operating conditions as well as providing DR services according to market price signals. © 2020 IEEE.

World University root node

Department of Electrical Engineering

IEEE PES Innovative Smart Grid Technologies Conference Europe

Transactive control of air-conditioning systems in buildings for demand response

In this paper, we design erasure-correcting codes for channels with burst and random erasures, when a strict decoding delay constraint is in place. We consider the sliding-window-based packet erasure model proposed by Badr et al., where any time-window of width w contains either up to a random erasures or an erasure burst of length at most b. One needs to recover any erased packet with a strict decoding delay deadline of tau , where erasures are as per the channel model. Presently existing rate-optimal constructions in the literature require, in general, a field-size which grows exponential in tau , as long as frac {a}{tau } remains a constant. In this work, we present a new rate-optimal code construction covering all channel and delay parameters, which requires an O(tau {2}) field-size. As a special case, when (b-a)=1 , we have a field-size linear in tau . We also present two other constructions having linear field-size, under certain constraints on channel and decoding delay parameters. As a corollary, we obtain low field-size, rate-optimal convolutional codes for any given column distance and column span. Simulations indicate that the newly proposed streaming code constructions offer lower packet-loss probabilities compared to existing schemes, for selected instances of Gilbert-Elliott and Fritchman channels. © 1963-2012 IEEE.

Department of Data Science

IEEE Transactions on Information Theory

Rate-Optimal Streaming Codes for Channels with Burst and Random Erasures

Though the merits of matrix-based dual-active-bridge (MB-DAB) as a grid-connected Solid-State-Transformer (SST) submodule have been presented in literature lately, its operation and control in the cascaded configuration have not been explored. The objective of this paper is to present the operation and control challenges of the cascaded matrix-based dual-active-bridge (CMB-DAB) in detail, from the perspective of the Medium-Voltage-AC (MVAC) to Low-Voltage-DC (LVDC) conversion stage of a grid-connected SST. Subsequently, the control strategy required to eliminate the unavoidable power imbalance issue is explained comprehensively. The simulation results are presented for a 7-level 52.65 kVA CMB-DAB converter to demonstrate the inevitable power imbalance issue and the proposed control strategy as a mitigation technique. The proposed power balance controller (PBC) is observed to perform smoothly in adjunction with the LVDC bus control and remediate power imbalances during steady-state as well as transient-states by adding suitable phase-shift correction terms. © 2020 IEEE.

9th IEEE International Conference on Power Electronics, Drives and Energy Systems, PEDES 2020

Power balance control of cascaded matrix-based dual-active-bridge converter

In this paper, a three-phase matrix-based AC to DC power converter is presented considering all the practical implementation aspects for battery charging applications. Unlike some of the matrix-based proposal in the literature, the proposed converter uses only six gate drivers for converting three-phase AC to medium-frequency AC, which is then stepped down and rectified to an appropriate voltage for battery interface. Managing energy stored in transformer's leakage inductor is often a problem while utilizing single driver per matrix switch. An additional short-circuit leg is proposed to circulate the stored energy during zero vector periods of the proposed converter, thereby ensuring continuous path for the leakage energy. The analysis and design of the proposed converter is validated on a 2 kW experimental prototype and test results are presented for validation. © 2020 IEEE.

Analysis and implementation of a three-phase matrix-based isolated AC-DC converter with transformer leakage energy management

Cascaded H-bridge (CHB) multilevel converter is widely used for medium voltage motor drives, Static Synchronous Compensator (STATCOMs) and solid-state transformers because of its advantages such as modular design, low harmonic distortion of input current and lower grid-side filter requirements compared to two-level converters. Among the failures in active devices, detection and localization of open-circuit (OC) faults either due to bond-wire lift off (device-side failures) or malfunction of gate driver (drive-side failures) are extensively studied. In this paper, fault detection and localization methods proposed in literature for CHB multilevel converters are analyzed and compared with respect to the time taken for fault localization and additional sensor requirements. For ease of understanding, the methods are classified as model-based, feature-based and hardware-based, and suitability of each classification is recommended for different applications. © 2020 IEEE.

IECON Proceedings (Industrial Electronics Conference)

Survey of Open-circuit Fault Detection and Localization Methods Applicable to Cascaded H-bridge Multilevel Converters

We consider the problem {−Δu=λK(x)f(u)in B1 c,u=0on ∂B1,u(x)→0as |x|→∞, where B1 c={x∈Rn||x|&gt;1},n&gt;2, λ is a positive parameter, K belongs to a class of functions which satisfy certain decay assumptions and f belongs to a class of functions which are asymptotically linear and may be singular at the origin. We prove the existence of positive solutions to such problems for certain values of parameter λ. Existence results to similar problems in Rn are also obtained. Our existence results are proved using the Schauder fixed point theorem and the method of sub and super solutions. © 2020}, author_keywords={Asymptotically linear reaction term; Infinite semipositone; Method of sub and super solutions; Schauder fixed point theorem; Semilinear elliptic problems; Unbounded domains}, funding_details={Department of Science and Technology, Ministry of Science and Technology, IndiaDepartment of Science and Technology, Ministry of Science and Technology, India, DST, DST/INSPIRE/04/2014/002833}, funding_text_1={This research was supported by the INSPIRE faculty award, awarded by the Department of Science and Technology , Government of India ( DST/INSPIRE/04/2014/002833 ).}, references={Abebe, A., Chhetri, M., Sankar, L., Shivaji, R., Positive solutions for a class of superlinear semipositone systems on exterior domains (2014) Bound. Value Probl., 2014. , 9 pp; Allegretto, W., Huang, Y.X., A Picone's identity for the p-Laplacian and applications (1998) Nonlinear Anal., 32 (7), pp. 819-830; Amann, H., Fixed point equations and nonlinear eigenvalue problems in ordered Banach spaces (1976) SIAM Rev., 18 (4), pp. 620-709; Ávila, A.I., Brock, F., Asymptotics at infinity of solutions for p-Laplace equations in exterior domains (2008) Nonlinear Anal., 69 (5-6), pp. 1615-1628; Castro, A., Sankar, L., Shivaji, R., Uniqueness of nonnegative solutions for semipositone problems on exterior domains (2012) J. Math. Anal. Appl., 394 (1), pp. 432-437; Chhetri, M., Drábek, P., Principal eigenvalue of p-Laplacian operator in exterior domain (2014) Results Math., 66 (3-4), pp. 461-468; Cui, S., Existence and nonexistence of positive solutions for singular semilinear elliptic boundary value problems (2000) Nonlinear Anal., 41 (1-2), pp. 149-176; Drábek, P., Sankar, L., Singular quasilinear elliptic problems on unbounded domains (2014) Nonlinear Anal., 109, pp. 148-155; Fleckinger-Pellé, J., Gossez, J.-P., de Thélin, F., Principal eigenvalue in an unbounded domain and a weighted Poincaré inequality (2006) Contributions to Nonlinear Analysis, Progr. Nonlinear Differential Equations Appl., 66, pp. 283-296. , Birkhäuser Basel; Hai, D.D., On an asymptotically linear singular boundary value problems (2012) Topol. Methods Nonlinear Anal., 39 (1), pp. 83-92; Hai, D.D., Sankar, L., Shivaji, R., Infinite semipositone problems with asymptotically linear growth forcing terms (2012) Differ. Integral Equ., 25 (11-12), pp. 1175-1188; Hai, D.D., Williams, J.L., Positive radial solutions for a class of quasilinear boundary value problems in a ball (2012) Nonlinear Anal., 75 (4), pp. 1744-1750; Ko, E., Lee, E.K., Shivaji, R., Multiplicity results for classes of singular problems on an exterior domain (2013) Discrete Contin. Dyn. Syst., 33 (11-12), pp. 5153-5166; Lee, E.K., Sankar, L., Shivaji, R., Positive solutions for infinite semipositone problems on exterior domains (2011) Differ. Integral Equ., 24 (9-10), pp. 861-875; Rajendran, D., Tyagi, J., Existence of nonnegative solutions to positone-type problems in R̂N with indefinite weights (2010) Electron. J. Differ. Equ., 2010. , 16 pp}, correspondence_address1={Sankar, L.; Indian Institute of TechnologyIndia; email: lakshmi@iitpkd.ac.in}, publisher={Academic Press Inc.}, issn={0022247X}, language={English}, abbrev_source_title={J. Math. Anal. Appl.}, document_type={Article}, source={Scopus},

Department of Mathematics

Journal of Mathematical Analysis and Applications

Singular semilinear elliptic problems with asymptotically linear reaction terms

Binary neutron star mergers (BNSMs) are currently the most promising source of r-process thanks to the detection of GW170817. The estimated occurring frequency and the amount of mass ejected per merger indicate that BNSMs by themselves can account for all the r-process enrichment in the Galaxy. However, the decreasing trend of [Eu/Fe] versus [Fe/H] of disk stars for [Fe/H] ⪆ -1 in the solar neighborhood is inconsistent with the flat trend expected from BNSMs with a standard delay time distribution (DTD) ∝ t -1. This has led to the suggestion that either additional sources or modification to the DTD of BNSMs is required to match the observations. We investigate the effects of natal kicks received during the birth of neutron star binaries on the chemical evolution of r-process element Eu in the Milky Way by combining the results from the galactic dynamics code galpy with a one-zone Galactic chemical evolution model omega. We show that when key inputs from simulations of the inside-out disk evolution are combined with natal kicks, BNSMs can naturally reproduce the observed decreasing trend of [Eu/Fe] with [Fe/H] in the solar neighborhood without the need for modification to the DTD or additional r-process sources. © 2020. The American Astronomical Society. All rights reserved..