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Item PV Powered Performance Enhanced Three-stage Cascaded quasi Z-source Inverter fed Induction Motor Drive(2015-09-03T10:00:48Z) Nisha, K C R; Sanjay, JainThis paper proposes the use of performance enhanced multi-stage Cascaded quasi Z-source Inverter (CqZSI) topology for adjustable speed drives in Photo Voltaic (PV) applications. For the same boost factor, a new PV powered three-stage CqZSI system has an advantage of lesser shoot-through duty ratio compared to the disadvantage of traditional ZSI with very less boost ratio, increased shoot-through ratio and high component stress at the power switches. A 25% reduction in shoot-through duty cycle is achieved by using the three-stage cascaded solution. The boost factor of the proposed system is 1.5 times higher than single-stage system for the same input voltage. Simulation of the three-stage CqZSI fed induction motor drive is done and verified by experimental results. The performance of the cascaded three-stage qZSI system is compared based on efficiency boost factor and shoot through performance. This paper illustrates that the performance enhanced CqZSI topology is a good alternative topology for efficient and highly reliable PV power generation system.Item Solar Powered Switched-Capacitor Reduced-source DC-link Impedance-source Inverter System(2015-09-03T09:52:57Z) Nisha, K C R; Sanjay, JainThe current fed impedance source inverter that was proposed earlier exhibits the same features of buck-boost inverter in a single stage. These Z-source inverters are more sturdy and reliable as they are vulnerable to electromagnetic noises. But the boosting gain of classical impedance source inverters is compromised by low modulation index and high component stress across the devices. To overcome these limitations of current fed impedance source inverter, this paper deals with a high performance switched capacitor reduced source DC-link Z-source. This utilizes the switched capacitor concept to the reduced source DC-link EZSI to achieve the strong boosting ability in short open-circuit period. Simulation of solar powered SC-DC-link EZ-source CSI system is performed. The proposed current-fed impedance-source topology has high boost ratio with less voltage stress than the classical current-fed inverters. The operating principle and the topological analysis are given. Boost factor performance and inductor current as a function of open-circuit ratio of the proposed SC-DC-EZSI system is compared with SC-EZSI system and the results are presented.Item Duality Theorem for Discrete Hartley Transform(2015-08-29T08:40:12Z) Madhukar, B.N; Sanjay, Jain; Satyanarayana, P.SThis paper presents a new property called the Duality Theorem for Continuous Hartley Transform (CHT). Hartley Transform is an integral transform related to the renowned Fourier Transform but has remained in the oblivion from mathematicians and engineers alike. Many of the properties of the Hartley Transform are akin to those of the Fourier Transform subject to minor differences. A formal derivation of the Duality Theorem corresponding to Continuous Hartley Transform is given which was hitherto not mentioned or derived in the literature. The usage of Duality Theorem helps in finding the time-domain function from the Hartley frequency domain and vice versa thereby reducing considerable labour involved in integration and computation time.Item Formant Estimation of Speech Using Discrete Hartley Transform(2015-08-04T07:34:25Z) Madhukar, B N; Sanjay, Jain; Satyanarayana, P. S.This paper presents a new method for formant estimation of speech signal using Discrete Hartley Transformapproach. Hitherto, the formant estimation of speech was carried out in temporal and frequency domains using Discrete Fourier Transform (DFT) based approach. A new approach of accomplishing this in the frequency domain using DHT, rather than using the DFT, is proposed. DFT, being a complex transform, takes more computation time for finding the formant frequencies of the speech signal, but DHT being a real transform takes less computation time to do the same with less memory requirement. The relationship between DFT and DHT is made use of for computing the formants, rather than using the DFT directly. The usage of DHT method is found to be optimal than using the direct DFT approach thereby saving implementation cost substantially in the formant estimation of speech signals. The analysis is done by comparing the usage of DFT directly on the speech signal and then using DHT, there by seeing the performance of these mathematical transforms based on computation time, which is used as a performance metric for validating the veracity of performance of the two discrete transforms concerned.Item PV Powered Switched-Inductor Embedded DC-link Impedance-source Inverter System(2015-06-19T05:16:51Z) Nisha, K C R; Dharmambal, V; Sanjay, JainBackground: The traditional embedded impedance-source inverter topology exhibits the disadvantages of low boost factor and higher cost due to additional PV sources. Objective: This research paper deals with the performance improvisation of embedded impedance-source inverter topology called Switched-Inductor DC-link Embedded Zsource Inverter (SL-DC-link EZSI). Switched inductor concept is employed to the reduced source DC-link EZSI to achieve the strong boosting ability in terms of short shoot-through period. Results: Simulation of PV powered SL-DC-EZSI fed induction motor drive is performed. The operating principle and the topological analysis are given. Boost factor performance, capacitor voltage and DC-link voltages as a function of shoot-through ratio of the SL-EZSI system is compared with the proposed SL-DClink EZSI system and the results are presented. Conclusion: PV powered Switched inductor DC-link EZSI topology is proposed and the results are presented. The propounded topology has the characteristics of high boost ratio, minimum shoot through period, reduced voltage stress and low cost.Item Duality Theorems For Infinite Fourier Cosine And Sine Transforms(2015-06-18T04:12:14Z) Madhukar, B N; Sanjay, Jain; Satyanarayana, P SThis paper presents two new properties called Duality Theorems, exclusively each for the Infinite Fourier Cosine and Fourier Sine Transforms respectively, which were hitherto not mentioned or given elsewhere in the literature. These two integral ransforms which are derived from the Fourier Integral and the Infinite Fourier Transform are well known in the mathematical and engineering fraternity and are used in a variety of applications. The Infinite Fourier Cosine and Sine Transforms have their own interesting properties. In this paper, we present formal derivations of the Duality Theorems for these two transforms. The usage of the Duality Theorems help in finding the time – domain function from the Infinite Fourier Cosine and Sine Transforms’ (frequency) domain and vice versa thereby reducing considerable labour and computation time involved in Integration, if a known Infinite Fourier Sine and Cosine Transform pair is known. The usages of the Duality Theorems have been exemplified with suitable illustrative examples.Item Cross Layer Analysis of Spectrum Sensing in the Cognitive Radio Paradigm(2015-06-03T10:34:57Z) Anandteerth, Mathad S; Mrinal, SarvagyaIn this paper, the performance of the carrier sense multiple access with collision avoidance (CSMA/CA) protocol at MAC layer with sensing errors at physical layer is investigated. Here the sensing errors are captured by modifying the Markov chain model widely used for the CSMA/CA analysis called Bianchi’s model. We investigate the throughput as a function of carrier sensing error probabilities: probability of missed detection and probability of false alarm for given CSMA/CA parameters. The normalized saturation throughput of CSMA/CA networks under the presence of sensing error is obtained. With imperfect carrier sensing, the false alarm error has an effect of extending the contention window size, and the missed detection error results in effects like shrinking the contention window etc. We also emphasize on the packet length (L) on the performance of the system under the presence of these errors.Item Duality Theorem For Infinite Hankel Transform(2015-05-06T05:16:07Z) Madhukar, B N; Sanjay, Jain; Satyanarayana, P. SThis paper presents a new property called the Duality Theorem for the Infinite Hankel Transform. Infinite Hankel Transform or simply Hankel Transform is an integral transform related to the renowned Fourier Transform that finds applications in electromagnetics, heat power and a host of other applications. A formal derivation of the Duality Theorem corresponding to the Infinite Hankel Transform is given which was hitherto not mentioned or derived in the literature. The usage of Duality Theorem helps in finding the time-domain function from the Hankel Transform domain and vice versa thereby reducing considerable labour and computation time, if a known Hankel Transform pair is available and the same has been exemplified with suitable illustrative examples.