Browsing by Author "Mandal, S."

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A balancing between super transparency and conductivity of solution combustion derived titanium doped indium oxide: Effect of charge carrier density and mobility
(Elsevier B.V., 2018) Pujar, P.; Vardhan, R.V.; Gupta, D.; Mandal, S.
In this contribution, super transparent (~100%) and conducting In14Ti1O23 (Titanium doped Indium oxide; InTiO) films were reported via solution combustion processing with acetylacetone as fuel. Both bulk-powder and thin film systems were studied and revealed the efficacy of low temperature combustion synthesis which yielded crystalline InTiO powder at 150 °C and its film counterpart had shown pronounced crystalinity with temperature. Also, all films with varying annealing temperature were smooth with rms value ranging from 0.29 nm to 1.9 nm. In addition, the charge carrier density in all films found to be of the order 1019 cm?3, possessing highest transparency nearly equals to uncoated glass at an annealing temperature of 350 °C having maximum of ~67% metal-oxygen-metal framework (or lattice oxygen) confirmed via X-ray photoelectron spectroscopy. Also, the highest conductivity of 20 S/cm at an annealing temperature of 450 °C clearly conveyed the potential of solution combustion processing in the fabrication of ultra-transparent InTiO films with no sophistication in the film fabrication. © 2018
A comparative analysis of crustacean exoskeletons: structural, microstructural, morphological, and UV absorption studies
(Institute of Physics, 2024) Nowl, M.S.; Praveen, L.L.; Ambili, V.; Singh, S.; Samad, U.; Seikh, A.H.; Dutta, S.; Mandal, S.
This study aims to investigate the structural, thermal, and spectral characteristics, along with the ultra-violet (UV) absorption of various marine benthos exoskeletons, such as various species of crabs (Portunus sanguinolentus, Portunus pelagicus, Charybdis feriata) and mantis shrimp (Oratosquilla oratoria). Their unique properties and ability to survive in harsh oceanic environments make them interesting research subjects. This research utilized powder x-ray diffraction (XRD) analysis to determine the crystal structure of the benthic varieties. The sample surface was analyzed using high-resolution micrographs obtained from field-emission scanning electron microscopy (FESEM), which identified the presence of chitin and calcite in the marine benthos. This was further confirmed by differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FTIR). The optical characteristics were investigated using UV-visible spectroscopy. The proximate analysis revealed high protein content in the mantis shrimp exoskeleton compared to other crab species, highlighting its excellent UV absorption characteristics. Overall, this research has the potential to broaden our understanding of marine organisms, which can have potential applications in biotechnology and materials science to develop nature-inspired innovative materials sustainably. © 2024 The Author(s). Published by IOP Publishing Ltd.
A comparative study on enhancer and inhibitor of glycine–nitrate combustion ZnO screen-printed sensor: detection of low concentration ammonia at room temperature
(Springer, 2020) Manjunath, G.; Pothukanuri, P.; Mandal, S.
We report a comparative study on enhancing and inhibiting the sensing performance of Sr-doped ZnO (Sr0.01 Zn0.99O) and RuO2-activated Sr-doped ZnO heterostructured sensors towards the low concentration (? 50 ppm) of ammonia gas at ambient. Sub-microns sized with high specific surface area, high reactive, oxygen-deficient Sr-doped ZnO particles were synthesized at low temperature (196 °C) through facile glycine–nitrate solution combustion synthesis (SCS) method. Porous, adhered screen-printed film of Sr-doped ZnO with optical bandgap (3.22 eV) was dip-coated using 0.02 M RuCl3 aqueous solution to obtain RuO2 activation. Smaller crystallite size and lesser lattice distortion obtained with Sr-doping in ZnO enhance the gas response (S = 71) towards the 50 ppm of ammonia gas at room temperature. RuO2-activated Sr-doped ZnO sensor associated with lesser oxygen vacancies and a lower concentration of chemisorbed oxygen species due to passivation layer and no-spill-over activity of RuO2, which inhibits the gas response from 71 to 3. Sr-doped ZnO-based sensor shows high selectivity towards ammonia against 50 ppm of volatile organic compound (VOCs) vapor. Expeditious sensor kinetics (response time and recovery time) in the Sr-doped ZnO sensor was observed, in which smaller crystallite size offers a shorter distance for the diffusion of oxygen vacancies (Vo). Ultra-high-sensitive and selective sensors with ease and economical fabrication offer feasibility in industries and domestic applications where detection of the less concentration ammonia vapor is crucial. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.
A Design and Implementation of a Novel Multi-Stage Ultra High Gain DC-DC Converter with Active LC2D Network
(Institute of Electrical and Electronics Engineers Inc., 2023) Mandal, S.; Prabhakaran, P.
This paper presents a novel multi-stage ultra-high gain DC-DC converter with minimal components, including a single semiconductor switch. It achieves high voltage gain at lower duty ratios, reducing voltage stress on the switch and diodes. The converter utilizes a network of an active inductor, capacitor, and two diodes, known as LC2D network (also called as active switched inductor capacitor network (SLCN)). The analysis focuses on the converter's performance derived from the n-stage SLCN converter, with emphasis on the basic stage. The compact design makes it suitable for renewable energy, electric vehicles, and fuel cell applications. The working principle and steady-state analysis are explained, supported by simulation results to validate the theoretical analysis. This innovative converter offers exceptional performance and has various applications. Â© 2023 IEEE.
A Design and Implementation of a Novel Multi-Stage Ultra High Gain DC-DC Converter with Boost Cell Network
(Institute of Electrical and Electronics Engineers Inc., 2023) Mandal, S.; Prabhakaran, P.
This paper introduces a novel multi-stage ultrahigh gain DC-DC converter featuring a minimal component count, including a single semiconductor switch. This converter achieves substantial voltage gain even at lower duty ratios, effectively reducing voltage stress on both the switch and diodes. The proposed converter leverages two distinct boost cell configurations, namely the 2LC2D and C2D designs. The 2LC2D boost cell consists of two inductors, one capacitor, and two diodes, collectively forming an active switched inductor capacitor network (SLCN). On the other hand, the C2D boost cell comprises one capacitor and two diodes. The paper primarily investigates the converter's performance within the context of an n-stage SLCN converter, with a particular focus on the fundamental stage. Its compact design renders it well-suited for various applications, including renewable energy, electric vehicles, and fuel cells. The paper provides a comprehensive explanation of the working principle and steady-state analysis, accompanied by simulation results that substantiate the theoretical findings. This innovative converter demonstrates exceptional performance characteristics and exhibits significant potential across a wide spectrum of applications. Â© 2023 IEEE.
A facile, low temperature spray pyrolysed tungsten oxide (WO3): an approach to antifouling coating by amalgamating scratch resistant and water repellent properties
(Springer, 2020) Vardhan, R.V.; Kumar, S.; Mandal, S.
In this study, a facile spray pyrolysed hydrophobic robust tungsten oxide (WO3) films were deposited at an annealing temperature of 400°C on inexpensive glass substrates, using clear and homogeneous precursor solution containing tungsten hexachloride and 2-methoxyethanol. The 10 and 15 times sprayed films were polycrystalline with the monoclinic crystal structure, uniform with the submicron-sized grain morphology (size ~320–420 nm), with an average surface roughness ranging from 12 to 17 nm and transparent above 60% in the visible region with a thickness of 380 and 550 nm, respectively. Elemental existence of tungsten and oxygen was recognized on the surface of the films possessing the highest lattice oxygen percentage of 91.1. Increment in the scratch hardness of the films with the number of sprays compared to uncoated glass was identified. The films were hydrophilic in nature (water contact angle <8°), converted to hydrophobic (>120°) by treating chemically with octadecyltrichlorosilane to form a self-assembled monolayer on the top and the hydrophobicity remained same (~120°) even after a year. These films with unique and combined properties of scratch hardness and hydrophobicity can serve in the potential application as antifouling coatings. © 2020, Indian Academy of Sciences.
A Non-isolated Bidirectional Buck-Boost DC-DC Converter with Minimum Component Count
(Institute of Electrical and Electronics Engineers Inc., 2024) Mandal, S.; Prabhakaran, P.
This paper presents a novel non-isolated high gain DC-DC converter designed to perform bidirectional buck boost operations in both the power flow directions efficiently. The converter is engineered with an emphasis on simplicity, utilizing a minimal number of components. Its standout feature lies in its broad duty ratio range, enhancing adaptability to meet the specific demands of renewable energy sources and electric vehicle applications. Noteworthy for its straightforward control and design characteristics, the proposed topology employs small signal analysis and the K-factor method for controller design. To rigorously validate the performance, open-loop and closed loop simulations of the proposed converter are conducted using MATLAB Simulink, considering a power level of 300 watts. This comprehensive examination ensures a thorough understanding of the converter's behavior and effectiveness in various operational scenarios. Â© 2024 IEEE.
A Non-isolated Step-up DC-DC Converter Based on Modified Quadratic Boost and Cuk Converter
(Institute of Electrical and Electronics Engineers Inc., 2024) Mandal, S.; Prabhakaran, P.; Adib, M.
This paper presents a novel non-isolated high-gain DC-DC converter engineered for optimal efficiency. This converter boasts a remarkably simple structure and employs a minimal number of components. Its standout characteristic is its wide duty ratio range, which significantly enhances adaptability to suit the diverse requirements of renewable energy sources (RES) and electric vehicle (EV) applications. The proposed converter integrates the quadratic boost and modified Cuk converter designs to obtain enhanced gain and performance. Additionally, this converter offers the advantage of utilizing just one switch, leading to simplified circuitry and reduced complexity. Furthermore, the voltage stress across the switch is maintained at a low level, contributing to improved reliability and reduced cost. A brief analysis and simulation results are presented to validate the efficacy of the proposed converter. Â© 2024 IEEE.
A Novel Active Switched-Inductor Based Hybrid Boost-Cuk Converter with High Voltage Gain
(Institute of Electrical and Electronics Engineers Inc., 2023) Prasad, S.; Mandal, S.; Prabhakaran, P.; Arun Dominic, D.
This paper presents a novel transformer less high gain DC-DC converter based on active switched inductor. The proposed converter features high voltage gain with reduced voltage stress across the power switch compared to the state-of-the-art converter topologies with same component count. The continuous input current of the converter facilitates suitable interface of a low voltage solar PV source to DC or AC grid having higher voltage level. Moreover, due to its bidirectional feature, the proposed converter is capable of interfacing battery or ultracapacitor to the traction inverter in an EV drive train. This paper illustrates operating principle and steady-state analysis of the proposed converter. Dynamic modelling and controller design have been discussed to regulate input current and output voltage of the converter. To validate the efficacy of the proposed converter, closed-loop simulation results has been presented. Â© 2023 IEEE.
A Novel Bidirectional High Gain DC-DC Converter with Active Switched Inductor and Wide Voltage Conversion Ratio
(Institute of Electrical and Electronics Engineers Inc., 2023) Mandal, S.; Prabhakaran, P.
Energy storage devices are indispensable for ensuring voltage and frequency stability in renewable energy sources such as solar and wind. Distributed generation systems necessitate bidirectional DC-DC converters to facilitate charge and discharge operations in accordance with operational requirements. In this paper, we introduce a new bidirectional DC-DC converter tailored to achieve substantial voltage gain while minimizing switch stress and maintaining a minimal component count. The proposed converter operates in buck mode for one power flow direction and boost mode for the other, ensuring continuous input and output current and reduced charging/discharging ripple. Comprehensive details regarding the derivation, operational principles, and meticulous steady-state analysis of the proposed converter are presented in this paper. Furthermore, a dynamic model of the converter is provided, and the design of closed-loop controllers for current control modes is outlined. We present extensive analysis and simulation results to illustrate the efficacy and performance of this novel topology. In summary, this converter offers a promising solution for achieving high-efficiency energy transfer with significant voltage gain, making it suitable for a wide array of applications. Â© 2023 IEEE.
A Novel Bidirectional Modified SEPIC Converter with Wide Voltage Conversion Ratio
(Institute of Electrical and Electronics Engineers Inc., 2023) Mandal, S.; Prabhakaran, P.
A Novel, transformer-less, bidirectional DC-DC Converter based on modified SEPIC topology is proposed in this paper. In the proposed converter, an active switched inductor configuration is incorporated in the conventional SEPIC converter to achieve a wide voltage conversion ratio with reduced voltage and current stress across the components. The proposed converter supports bidirectional buck-boost (BBB) capability with low components. The proposed converter's operating principle and steady-state analysis are explained in detail for continuous conduction mode (CCM). Dynamic modelling of the converter is presented and closed-loop controllers are designed. The proposed converter operates in both current and voltage control modes. The design of voltage and current compensators are detailed in this paper. Detailed analysis and simulation results are presented to validate the theoretical analysis and performance of the proposed converter. Â© 2023 IEEE.
A Novel Bidirectional Modified SEPIC-Cuk Converter with Wide Voltage Conversion Ratio
(Institute of Electrical and Electronics Engineers Inc., 2023) Mandal, S.; Prabhakaran, P.
The paper proposes a novel transformer-less bidirectional DC-DC converter that achieves ultra-high gain and reduces voltage stress across components. This converter is based on modified SEPIC and CUK topologies, and its derivation, operating principle, and steady-state analysis are presented. The paper also includes dynamic modeling of the converter and the design of closed-loop controllers for voltage and current control modes. Detailed analysis and simulation results are provided to demonstrate the efficacy and performance of the proposed topology. Overall, this innovative converter offers a promising solution for high-efficiency energy transfer with ultra-high voltage gain in various applications. Â© 2023 IEEE.
A Novel Bidirectional Modified Zeta Converter With Wide Voltage Conversion Ratio
(Institute of Electrical and Electronics Engineers Inc., 2025) Mandal, S.; Prabhakaran, P.
High-gain, nonisolated bidirectional dc–dc converters (BDCs) play a vital role in interfacing energy storage systems with microgrids and electric vehicles (EVs). However, the existing converters often operate within a limited duty cycle range and involve high component counts and significant voltage stress for achieving desired voltage gain. This article presents a novel noncoupled high-gain BDC that efficiently operates in the boost mode for forward power flow and buck mode for reverse power flow. Based on a modified zeta converter topology, the proposed converter offers a simplified circuit structure and control strategy, requiring fewer components. It achieves wide voltage gain across an extended duty cycle range while minimizing voltage stress on most switches. A 200-W prototype has been developed and tested in the laboratory to validate the converter’s performance. To enhance efficiency, SiC MOSFETs are utilized, achieving a peak efficiency of 96%. Experimental results confirm the converter’s suitability for both open-loop and closed-loop configurations, highlighting its potential for diverse applications in energy storage systems and EVs. © 2013 IEEE All rights reserved.
A Novel Bidirectional Modified Zeta Converter with Wide Voltage Conversion Ratio
(Institute of Electrical and Electronics Engineers Inc., 2023) Mandal, S.; Prabhakaran, P.
A Novel, transformer-less, bidirectional and high-gain DC-DC converter is proposed in this paper, which is apt for the interface between two DC voltage levels in various applications, including microgrids. This converter achieves a wide voltage gain with reduced voltage and current stress across the components. The proposed converter supports bidirectional capability with low components. The proposed converter's operating principle and steady-state analysis are explained in detail for continuous conduction mode (CCM). Dynamic modelling of the converter is presented, and closed-loop controllers are designed. The proposed converter operates in both current and voltage control modes. The design of voltage and current compensators are elaborated. Detailed analysis and simulation results are presented in this paper to validate the theoretical analysis and performance of the proposed converter. Â© 2023 IEEE.
A Novel Boost Derived Input-Parallel Output-Series DC-DC Converter for Bipolar DC Microgrid
(Institute of Electrical and Electronics Engineers Inc., 2023) Prasad, S.; Mandal, S.; Prabhakaran, P.; Arun Dominic, D.
This paper illustrates a novel converter called Input Parallel Output Series Boost Cuk (IPOSBC) converter, designed specifically for low-voltage bipolar DC microgrid (BPDCMG) applications. The converter features a single-input dual-output configuration and utilizes an interleaved structure to minimize current ripple when connected to renewable energy sources like solar PV or storage unit like battery in the BPDCMG. The paper presents a dynamic model of the proposed converter and develops a closed-loop controller for current and voltage control operation. By connecting dispatchable sources such as batteries to the input terminals, the IPOSBC converter can also function in voltage control mode to regulate the bus voltage of BPDCMG system. Furthermore, the paper discusses an intriguing method to mitigate voltage imbalance in the BPDCMG without an active source, utilizing the IPOSBC converter as a DC compensator, like an active shunt filter or D-STATCOM in AC systems. Here, the converter operates without supplying or consuming power, except for converter losses. Simulation results depicting various operating modes are presented to validate the effectiveness of the IPOSBC converter. Â© 2023 IEEE.
A Novel High Gain Unidirectional Buck-Boost DC-DC Converter with Active Switched-Inductor Configuration
(Institute of Electrical and Electronics Engineers Inc., 2023) Mandal, S.; Prabhakaran, P.
A Novel non-isolated buck-boost DC-DC Converter is proposed in this paper for high voltage gain (HVG) applications. The proposed converter has a voltage gain of 2/(1-d) times that of the conventional buck-boost converter and provides this gain with fewer components. An active switched inductor (ASI) is incorporated in the proposed converter, to mitigate voltage and current stress on the components, particularly in the high-voltage section. Apart from HVG in buck-boost mode, the proposed converter provides noninverting output voltage, and continuous input current without using any coupled inductor and transformer. Hence, the proposed converter is compact and is suitable for renewable energy and fuel cell applications. One notable advantage of the proposed topology is the minimized voltage stress experienced by the switches and intermediate capacitors. Detailed explanations are given regarding the working principle and steady-state analysis of this converter. Furthermore, the dynamic modeling of the converter allows for voltage and current control operations, and simulation results are presented to verify the theoretical analysis. Â© 2023 IEEE.
A Novel Input-Parallel Output-Series SEPIC-Cuk Converter for Bipolar Voltage Balancing
(Institute of Electrical and Electronics Engineers Inc., 2023) Prasad, S.; Mandal, S.; Prabhakaran, P.; Arun Dominic, D.
This article describes a novel Input-Parallel Output-Series SEPIC-Cuk (IPOSSC) converter formulated for application in low voltage bipolar DC microgrid (BDMG) systems. The proposed bi-directional converter adopts a single input dual output configuration with inherited common ground and employs an interleaved-structure to reduce source current fluctuations when linked to sustainable energy sources (SES) such as solar PV or energy storage elements (ESE) like batteries. The article includes the development of a dynamic model for this proposed circuit and formulates closed-loop controller for precise current and voltage regulation. Additionally, by integrating dispatchable sources like a battery into the source terminals, the IPOSSC can operate in voltage regulation mode to effectively control the bus voltage. Furthermore, the article explores an intriguing approach to counteract voltage unbalance in BDMG systems without relying on an active energy source connected to the source terminal. It harnesses the IPOSSC capabilities as a DC compensator, similar to an active shunt filter or D-STATCOM in AC systems, with the converter only incurring losses and not supplying or consuming power. The article substantiates the efficacy of the IPOSSC converter through simulation results depicting its performance in various operating modes. Â© 2023 IEEE.
A Novel Input-Parallel Output-Series SEPIC-Cuk Converter for Bipolar Voltage Balancing
(Institute of Electrical and Electronics Engineers Inc., 2023) Prasad, S.; Mandal, S.; Prabhakaran, P.; Arun Dominic, D.
This article describes a novel Input-Parallel Output-Series SEPIC-Cuk (IPOSSC) converter formulated for application in low voltage bipolar DC microgrid (BDMG) systems. The proposed bi-directional converter adopts a single input dual output configuration with inherited common ground and employs an interleaved-structure to reduce source current fluctuations when linked to sustainable energy sources (SES) such as solar PV or energy storage elements (ESE) like batteries. The article includes the development of a dynamic model for this proposed circuit and formulates closed-loop controller for precise current and voltage regulation. Additionally, by integrating dispatchable sources like a battery into the source terminals, the IPOSSC can operate in voltage regulation mode to effectively control the bus voltage. Furthermore, the article explores an intriguing approach to counteract voltage unbalance in BDMG systems without relying on an active energy source connected to the source terminal. It harnesses the IPOSSC capabilities as a DC compensator, similar to an active shunt filter or DSTATCOM in AC systems, with the converter only incurring losses and not supplying or consuming power. The article substantiates the efficacy of the IPOSSC converter through simulation results depicting its performance in various operating modes. Â© 2023 IEEE.
A Novel Non-Isolated DC-DC Converter with Active Switched-Inductor for High Voltage Gain Applications
(Institute of Electrical and Electronics Engineers Inc., 2022) Mandal, S.; Prabhakaran, P.
A Novel, Transformer-less DC-DC Converter for high voltage gain (HVG) applications is proposed in this paper. The proposed converter consists of an active switched inductor for HVG with reduced voltage and current stress across the components. The proposed converter has a voltage gain of (3D+1) times than that of the conventional boost converter. The proposed converter uses fewer components and provides HVG with relatively small duty ratios. A good feature of the proposed topology is all the switches and intermediate capacitors have equal voltage stress. The proposed converter can support bidirectional operation with wide duty ratio variations. The working principle and steady-state analysis of this converter is explained in detail. Dynamic modelling of the converter is presented, and both voltage and current control operations can be carried out. To validate the theoretical analysis, detailed simulation results are presented. Â© 2022 IEEE.
A Novel Non-Isolated High-Gain Boost DC- DC Converter with Single Switch and Minimum Component Count
(Institute of Electrical and Electronics Engineers Inc., 2024) Mandal, S.; Prabhakaran, P.
This paper presents a novel non-isolated unidirectional DC-DC converter aimed to achieve substantial voltage gain while minimizing component stress and maintaining a low component count. The converter's architecture amalgamates modified Single-Ended Primary Inductance Converter (SEPIC) and traditional Cuk topologies, employing only a single switch. A comprehensive analysis of the derivation, operational principles, and steady-state characteristics of this novel converter is provided. Additionally, the paper encompasses dynamic modeling of the proposed converter and elucidates the design of closed-loop controllers tailored for current control modes. Extensive analysis and simulation results substantiate the effectiveness and performance of the proposed topology. This innovative converter offers a promising solution for efficient energy transfer, delivering exceptional voltage gain suitable across various applications. Â© 2024 IEEE.