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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Root loci and sensitivities of two distributed, lumped, active filter structures

Faick, John Carleton, 1949- January 1974 (has links)
No description available.
2

Problems concerning nonstationary random processes

Sondhi, Man Mohan, January 1957 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1957. / Typescript. Abstracted in Dissertation abstracts, v. 17 (1957) no. 10, p. 2237. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 81-83).
3

Analysis of the Twin-T notch filter

Veed, Alan McDonald. January 1962 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1962. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf 67).
4

New configurations for RF/microwave bandstop and lowpass filters /

Peddibhotla, Harish V. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 79-81). Also available on the World Wide Web.
5

A study of nonideal log domain and differential Class AB filters /

Tola, Abdullah Tahsin, January 1999 (has links)
Thesis (Ph. D.)--Lehigh University, 2000. / Includes vita. Includes bibliographical references (leaves 232-236).
6

Doubly adaptive filters for nonstationary applications

Peters, S. Douglas 10 July 2018 (has links)
This dissertation examines the performance of self-tuning adaptive filters in non-stationary environments and deals with extensions to conventional adaptive filters that lead to enhanced performance. A number of the available self-tuning adaptive filters, called doubly adaptive filters for the present purposes, are critically examined and three new schemes are proposed. The first and second are based on the normalized least-mean-squares (NLMS) adaptive filter, and their formulations are contrived to minimize the misadjustment in a convergent scenario and random walk scenario, respectively. The first of these filters, called reduced adaptation state estimation (RASE), achieves performance near that of the recursive-least squares (RLS) algorithm under known additive noise statistics and moderately correlated input samples. The development of the second proposed filter introduces the idea of having more than one adaptive filter applied in parallel to the same input and desired signals. This concept, called parallel adaptation (PA), is applied in both NLMS and RLS contexts in order to achieve optimal steady-state misadjustment in a random walk scenario. Numerous simulation results are presented that support the present analysis and demonstrate the effectiveness of the proposed algorithms in a number of different nonstationary environments. / Graduate
7

Analysis and control of unified active power filter

Muthu, Subramanian 06 November 2017 (has links)
The combined series and shunt active filters have been proposed to alleviate the power quality problems at the demand-side power systems. They provide compensation for load reactive power, load harmonics, unbalanced loads, utility harmonics, utility disturbances and utility imbalance. However, the conventional approach for the control of the combined active filter systems have resulted in large operating capacity of the shunt active filter because reactive power compensation involves only the shunt active filter. Furthermore, the harmonic mitigation problems are handled mainly by indirect harmonic compensation schemes rather than direct harmonic isolation schemes. This thesis presents the analysis and control of Unified Active Power Filter(UAPF) and proposes a novel concept of load reactive power compensation involving both the series active filter and the shunt active filter. This new control strategy of the combined active filter is to achieve the reduction in KVA rating of the shunt active filter and the optimal operation with increased efficiency. The thesis also applies discretetime sliding-mode control technique to enhance the performance of the combined active filter system in terms of fast dynamic response and effective solution to harmonic mitigation problems. The thesis also presents simulation and experimental results to provide verification of the proposed UAPF concept. In this thesis, the involvement of series active filter for reactive power compensation is achieved by controlling the phase difference between the load voltage and the utility voltage. The complete steady-state operating characteristics of UAPF are analyzed with the identification of the different operating modes of UAPF and the analysis of active and reactive power handled by the active filter components. The results of the analysis are shown to provide an insight about the load reactive power compensation by the series and shunt active filter. The reduction in ratings of the shunt active filter is demonstrated by an apparent power analysis of active filter components. The results of the analysis are also useful to design and select the optimal operating point for UAPF. The performance of UAPF to meet the stringent power quality standards are realized by applying discrete-time sliding-mode control schemes for the load voltage regulation and the active power factor correction. Various voltage and current control techniques used for three-phase voltage-source inverters are surveyed to identify the discrete-time sliding mode control technique as the suitable one. A generalized design procedure is derived for the control of power converter systems and the control scheme is extended to the load voltage control of shunt active filter and the line current control of series active filter. The control algorithms are developed to track a given load voltage and line current reference signals respectively. The effect of computational delay in DSP implementation is studied extensively and the control law is designed with the consideration for the computational delay. The systematic approach for the design of DC link voltage regulation is also presented in this thesis. A prototype experimental setup including the power circuit for UAPF and DSP based control circuit is built to implement the control and to verify the performance characteristics of UAPF. A real-time control algorithm is developed and is implemented on a DSP TMS320C40 system with PWM implementation by DMA without the intervention of CPU. The steady-state operating characteristics of UAPF is investigated by experiments. The operation of UAPF at the optimal operating point is shown to reduce the ratings of the shunt active filter and to improve the efficiency. The steady-state operation and the dynamic response of discrete-time sliding mode load voltage control and utility line current control are examined by simulation and experiments. The invariance property and the robustness property of the discrete-time sliding mode control are also demonstrated by the experimental results. With the discrete-time sliding mode control, the compensation characteristics of UAPF are shown to meet the stringent power quality standards. / Graduate
8

Audio band integrated active RC filter with digital frequency tuning.

January 2005 (has links)
Yeung Nang Ching. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 72-74). / Abstracts in English and Chinese. / ACKNOWLEDGMENTS --- p.I / ABSTRACT --- p.II / 摘要 --- p.III / TABLE OF CONTENTS --- p.IV / LIST OF FIGURES --- p.VII / LIST OF TABLES --- p.X / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Overview of filter --- p.1 / Chapter 1.1.1 --- History --- p.1 / Chapter 1.1.2 --- Application of analog filter --- p.2 / Chapter 1.1.3 --- Category of continuous time filters --- p.3 / Chapter 1.1.4 --- Problem issued from Active RC filter --- p.7 / Chapter 1.2 --- Motivation --- p.7 / Chapter 1.3 --- Outline --- p.8 / Chapter CHAPTER 2 --- FILTER FUNDAMENTAL --- p.9 / Chapter 2.1 --- Overview --- p.9 / Chapter 2.2 --- Terminology --- p.9 / Chapter 2.3 --- General Goals of Filter Design --- p.11 / Chapter 2.4 --- Standard Lowpass Filter Characteristic --- p.11 / Chapter 2.4.1 --- Butterworth --- p.11 / Chapter 2.4.2 --- Chebyshev --- p.12 / Chapter 2.4.3 --- Elliptic-Function --- p.13 / Chapter 2.5 --- Study on Different Tuning Approaches --- p.13 / Chapter CHAPTER 3 --- CURRENT DIVISION NETWORK (CDN) --- p.18 / Chapter 3.1 --- Overview of Current Division Technique --- p.18 / Chapter 3.2 --- Second Order Effects --- p.23 / Chapter 3.3 --- Working Principle of CDN --- p.23 / Chapter 3.4 --- Performances of CDN --- p.25 / Chapter 3.4.1 --- General Properties of CDN --- p.25 / Chapter 3.4.2 --- Input Resistances of CDN --- p.26 / Chapter 3.4.3 --- Noise Performance of CDN --- p.27 / Chapter CHAPTER 4 --- REALIZATION OF THE FILTER --- p.31 / Chapter 4.1 --- Overview --- p.31 / Chapter 4.2 --- Traditional Kerwin Huelsman Newcomb (KHN) Biquad --- p.31 / Chapter 4.2.1 --- State Variable Method --- p.31 / Chapter 4.2.2 --- KHN Biquad --- p.32 / Chapter 4.3 --- Proposed Filter --- p.33 / Chapter 4.3.1 --- Biquad with CDN --- p.33 / Chapter 4.3.2 --- A dvantages of Proposed Filter --- p.36 / Chapter 4.3.3 --- Schematic of Proposed Filter --- p.38 / Chapter CHAPTER 5 --- LAYOUT CONSIDERATION --- p.41 / Chapter 5.1 --- Overview --- p.41 / Chapter 5.2 --- Process Information --- p.41 / Chapter 5.3 --- Transistor Layout Techniques --- p.42 / Chapter 5.3.1 --- Multi-finger Layout Technique --- p.42 / Chapter 5.3.2 --- Common-Centroid Structure --- p.43 / Chapter 5.3.3 --- Guard Ring --- p.45 / Chapter 5.4 --- Passive Element Layout Techniques --- p.45 / Chapter 5.5 --- Layout of Whole Design --- p.47 / Chapter CHAPTER 6 --- SIMULATION RESULT --- p.49 / Chapter 6.1 --- Operational Amplifier --- p.49 / Chapter 6.2 --- Overall Performance of filter --- p.55 / Chapter CHAPTER 7 --- MEASUREMENT RESULT --- p.60 / Chapter 7.1 --- Measurement Setup --- p.60 / Chapter 7.2 --- Time Domain Measurement --- p.62 / Chapter 7.3 --- Frequency Domain Measurement --- p.63 / Chapter 7.4 --- Measurement of Non-Linearity --- p.66 / Chapter 7.5 --- Summary of the Performance --- p.69 / Chapter 7.6 --- Comparison on Tuning Ability --- p.70 / Chapter CHAPTER 8 --- CONCLUSION --- p.71 / BIBLIOGRAPHY --- p.72
9

Design and implementation of LTCC filters with enhanced stop-band characteristics.

January 2001 (has links)
Leung Wing-Yan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 131-135). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Background Theory --- p.3 / Chapter 2.1 --- Low-Pass Network Synthesis --- p.3 / Chapter 2.2 --- Maximally Flat Attenuation Characteristic --- p.5 / Chapter 2.3 --- Chebysheff Attenuation Characteristic --- p.6 / Chapter 2.4 --- Low-Pass to Band-Pass Transformation --- p.8 / Chapter 2.5 --- Impedance- and Admittance- Inverters --- p.9 / Chapter 2.6 --- Coupled-Resonator Filters --- p.13 / Chapter Chapter 3 --- New Circuit Topologies for Band-Pass Filters --- p.18 / Chapter 3.1 --- Locations of Transmission Zeros --- p.18 / Chapter 3.2 --- Circuit Topologies for Generation of Transmission Zeros --- p.18 / Chapter 3.3 --- Zeros at Lower Stop-Band (Category 1) --- p.21 / Chapter 3.3.1 --- Capacitor Insertions --- p.21 / Chapter 3.3.2 --- Design Equations for Configuration I --- p.22 / Chapter 3.3.3 --- Design Equations for Configuration II --- p.24 / Chapter 3.3.4 --- Coupling between Components --- p.28 / Chapter 3.3.5 --- Design Equations for Configuration III --- p.28 / Chapter 3.4 --- Zeros at Upper Stop-Band (Category 2) --- p.32 / Chapter 3.4.1 --- Inductor Insertions --- p.32 / Chapter 3.4.2 --- Design Equations for Configuration IV --- p.33 / Chapter 3.4.3 --- Design Equations for Configuration V --- p.35 / Chapter 3.4.4 --- Coupling between Components --- p.38 / Chapter 3.4.5 --- Design Equations for Configuration VI --- p.39 / Chapter 3.4.6 --- Design Equations for Configuration VII --- p.43 / Chapter 3.5 --- Zeros at Both Lower and Upper Stop-band (Category 3) --- p.46 / Chapter 3.5.1 --- Component Insertions --- p.46 / Chapter 3.5.2 --- Design Equations for Configuration VIII --- p.49 / Chapter 3.5.3 --- Design Equations for Configuration IX-XI --- p.49 / Chapter 3.5.4 --- Coupling between components --- p.50 / Chapter 3.5.5 --- Design Equations for Configuration XII --- p.51 / Chapter Chapter 4 --- Design Considerations --- p.52 / Chapter 4.1 --- Analytical Limitation --- p.53 / Chapter 4.1.1 --- "Conventional Band-Pass Filter, Configuration II, III, V and VI" --- p.53 / Chapter 4.1.2 --- Configuration I --- p.55 / Chapter 4.1.3 --- Configuration II --- p.57 / Chapter 4.1.4 --- Configuration IV --- p.59 / Chapter 4.1.5 --- Configuration VII-XII --- p.61 / Chapter 4.1.6 --- Summary --- p.61 / Chapter 4.2 --- Practical Limitation --- p.62 / Chapter 4.2.1 --- Configuration I --- p.64 / Chapter 4.2.2 --- Configuration II --- p.65 / Chapter 4.2.3 --- Configuration III --- p.67 / Chapter 4.2.4 --- Configuration IV --- p.69 / Chapter 4.2.5 --- Configuration V --- p.71 / Chapter 4.2.6 --- Configuration VI --- p.73 / Chapter 4.2.7 --- Summary --- p.75 / Chapter 4.3 --- Comparisons between Different Configurations --- p.76 / Chapter 4.3.1 --- Category 1 (Transmission Zeros at Lower Stop-Band) --- p.76 / Chapter 4.3.2 --- Category 2 (Transmission Zeros at Upper Stop-Band) --- p.79 / Chapter 4.3.3 --- Category 3 (Transmission Zeros at both side of the Stop-Band) --- p.82 / Chapter Chapter 5 --- LTCC Technology --- p.84 / Chapter 5.1 --- Definition --- p.84 / Chapter 5.2 --- Fabrication Process --- p.85 / Chapter 5.3 --- Material Used --- p.86 / Chapter 5.3.1 --- Conductive Materials --- p.86 / Chapter 5.3.2 --- Ceramic Materials --- p.87 / Chapter 5.4 --- Advantages of LTCC Technology --- p.87 / Chapter 5.5 --- Recent Development in LTCC Technology --- p.89 / Chapter 5.6 --- Design Rules --- p.90 / Chapter 5.7 --- Realization of Passive Elements in LTCC --- p.91 / Chapter 5.7.1 --- Capacitors --- p.91 / Chapter 5.7.2 --- Inductors --- p.96 / Chapter 5.7.3 --- Effect of Ground Plane on Inductance Realization --- p.99 / Chapter Chapter 6 --- Implementation and Characterization of LTCC Band-Pass Filter --- p.101 / Chapter 6.1 --- Design Procedures --- p.101 / Chapter 6.2 --- Schematic Design of LTCC Filters --- p.103 / Chapter 6.2.1 --- Category1 --- p.103 / Chapter 6.2.2 --- Category2 --- p.104 / Chapter 6.2.3 --- Category3 --- p.105 / Chapter 6.3 --- Design and Optimization --- p.106 / Chapter 6.4 --- Performance Evaluation --- p.117 / Chapter 6.4.1 --- TRL Calibration Method --- p.119 / Chapter 6.4.2 --- Experimental Results --- p.126 / Chapter Chapter 7 --- Conclusion and Recommendations for Future Work --- p.129 / References --- p.131 / Author´ةs Publication --- p.135 / Appendix A CAD Tool for LTCC Circuit Prototyping --- p.136 / Appendix B Computer Program 1 Listing --- p.153 / Appendix C Computer Program 2 Listing --- p.170 / Appendix D Computer Program 3 Listing --- p.172
10

A comparison and assessment of hybrid filter topologies and control algorithms

Chen, Lijun 16 June 2000 (has links)
The harmonic problem in power systems is gaining more attention as incidences correlated with harmonics increase. Conventional passive filtering techniques for harmonic mitigation have inherent problems, and purely active filters have the disadvantages of higher costs and ratings. Hybrid active filters inherit the efficiency of passive filters and the improved performance of active filters, and thus constitute a viable improved approach for harmonic compensation. To date, there have been several literature works comparing passive and active filters for harmonic mitigation. However, there are currently no comparisons of possible hybrid active filters. This thesis presents an assessment and comparison of hybrid active filters, including their topologies and control algorithms. Three different topologies of hybrid active filters are simulated in PSpice version 9.0 to verify their feasibility for harmonic compensation. From the simulations, all three topologies have better performance over passive filters for harmonic compensation and are insensitive to parameter variations. In addition, the simulated hybrid active filter ratings are lower than can be achieved with purely active filters. A modified "p-q" theory is introduced for control strategy, which is more feasible for extracting harmonic components for distorted load voltages. This thesis concludes with a comprehensive comparison of the hybrid active filter characteristics. / Graduation date: 2001

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