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Electrical Circuits Lab. 0903219 Series RC Circuit Phasor Diagram
Electrical Circuits Lab. 0903219 Series RC Circuit Phasor Diagram - Simple steps to draw phasor diagram of a series RC circuit without memorizing: * Start with the quantity (voltage or current) that is common for the resistor R and the capacitor C, which is here the source current I (because it passes through both R and C without being divided). Figure (1) Series RC circuit * Now we know that I and resistor voltage VR are in phase or have the same phase angle (there zero crossings are the same on the time axis) and VR is greater than I in magnitude. * Since I equal the capacitor current IC and we know that IC leads the capacitor voltage VC by 90 degrees, we will add VC on the phasor diagram as follows: * Now, the source voltage VS equals the vector summation of VR and VC: Figure (2) Series RC circuit Phasor Diagram Prepared by: Eng. Wiam Anabousi - Important notes on the phasor diagram of series RC circuit shown in figure (2): A- All the vectors are rotating in the same angular speed ω. B- This circuit acts as a capacitive circuit and I leads VS by a phase shift of Ө (which is the current angle if the source voltage is the reference signal). Ө ranges from 0o to 90o (0o < Ө <90o). If Ө=0o then this circuit becomes a resistive circuit and if Ө=90o then the circuit becomes a pure capacitive circuit. C- The phase shift between the source voltage and its current Ө is important and you have two ways to find its value: a- b- = - = - D- Using the phasor diagram, you can find all needed quantities in the circuit like all the voltages magnitude and phase and all the currents magnitude and phase. -
A Centrality Measure for Electrical Networks
Carnegie Mellon Electricity Industry Center Working Paper CEIC-07 www.cmu.edu/electricity 1 A Centrality Measure for Electrical Networks Paul Hines and Seth Blumsack types of failures. Many classifications of network structures Abstract—We derive a measure of “electrical centrality” for have been studied in the field of complex systems, statistical AC power networks, which describes the structure of the mechanics, and social networking [5,6], as shown in Figure 2, network as a function of its electrical topology rather than its but the two most fruitful and relevant have been the random physical topology. We compare our centrality measure to network model of Erdös and Renyi [7] and the “small world” conventional measures of network structure using the IEEE 300- bus network. We find that when measured electrically, power model inspired by the analyses in [8] and [9]. In the random networks appear to have a scale-free network structure. Thus, network model, nodes and edges are connected randomly. The unlike previous studies of the structure of power grids, we find small-world network is defined largely by relatively short that power networks have a number of highly-connected “hub” average path lengths between node pairs, even for very large buses. This result, and the structure of power networks in networks. One particularly important class of small-world general, is likely to have important implications for the reliability networks is the so-called “scale-free” network [10, 11], which and security of power networks. is characterized by a more heterogeneous connectivity. In a Index Terms—Scale-Free Networks, Connectivity, Cascading scale-free network, most nodes are connected to only a few Failures, Network Structure others, but a few nodes (known as hubs) are highly connected to the rest of the network. -
Admittance, Conductance, Reactance and Susceptance of New Natural Fabric Grewia Tilifolia V
Sensors & Transducers Volume 119, Issue 8, www.sensorsportal.com ISSN 1726-5479 August 2010 Editors-in-Chief: professor Sergey Y. Yurish, tel.: +34 696067716, fax: +34 93 4011989, e-mail: [email protected] Editors for Western Europe Editors for North America Meijer, Gerard C.M., Delft University of Technology, The Netherlands Datskos, Panos G., Oak Ridge National Laboratory, USA Ferrari, Vittorio, Universitá di Brescia, Italy Fabien, J. Josse, Marquette University, USA Katz, Evgeny, Clarkson University, USA Editor South America Costa-Felix, Rodrigo, Inmetro, Brazil Editor for Asia Ohyama, Shinji, Tokyo Institute of Technology, Japan Editor for Eastern Europe Editor for Asia-Pacific Sachenko, Anatoly, Ternopil State Economic University, Ukraine Mukhopadhyay, Subhas, Massey University, New Zealand Editorial Advisory Board Abdul Rahim, Ruzairi, Universiti Teknologi, Malaysia Djordjevich, Alexandar, City University of Hong Kong, Hong Kong Ahmad, Mohd Noor, Nothern University of Engineering, Malaysia Donato, Nicola, University of Messina, Italy Annamalai, Karthigeyan, National Institute of Advanced Industrial Science Donato, Patricio, Universidad de Mar del Plata, Argentina and Technology, Japan Dong, Feng, Tianjin University, China Arcega, Francisco, University of Zaragoza, Spain Drljaca, Predrag, Instersema Sensoric SA, Switzerland Arguel, Philippe, CNRS, France Dubey, Venketesh, Bournemouth University, UK Ahn, Jae-Pyoung, Korea Institute of Science and Technology, Korea Enderle, Stefan, Univ.of Ulm and KTB Mechatronics GmbH, Germany -
C I L Q LC Circuit
Your Comments I am not feeling great about this midterm...some of this stuff is really confusing still and I don't know if I can shove everything into my brain in time, especially after spring break. Can you go over which topics will be on the exam Wednesday? This was a very confusing prelecture. Do you think you could go over thoroughly how the LC circuits work qualitatively? I may have missed something simple, but in question 1 during the prelecture why does the charge on the capacitor have to be 0 at t=0? I feel like that bit of knowledge will help me with the test wednesday I remember you mentioning several weeks ago that there was one equation you were going to add to the 2013 equation sheet... which formula was that? Thanks! Electricity & Magnetism Lecture 19, Slide 1 Some Exam Stuff Exam Wed. night (March 27th) at 7:00 Covers material in Lectures 9 – 18 Bring your ID: Rooms determined by discussion section (see link) Conflict exam at 5:15 Don’t forget: • Worked examples in homeworks (the optional questions) • Other old exams For most people, taking old exams is most beneficial Final Exam dates are now posted The Big Ideas L9-18 Kirchoff’s Rules Sum of voltages around a loop is zero Sum of currents into a node is zero Kirchoff’s rules with capacitors and inductors • In RC and RL circuits: charge and current involve exponential functions with time constant: “charging and discharging” Q dQ Q • E.g. IR R V C dt C Capacitors and inductors store energy Magnetic fields Generated by electric currents (no magnetic charges) Magnetic -
Electrical Impedance Tomography
INSTITUTE OF PHYSICS PUBLISHING INVERSE PROBLEMS Inverse Problems 18 (2002) R99–R136 PII: S0266-5611(02)95228-7 TOPICAL REVIEW Electrical impedance tomography Liliana Borcea Computational and Applied Mathematics, MS 134, Rice University, 6100 Main Street, Houston, TX 77005-1892, USA E-mail: [email protected] Received 16 May 2002, in final form 4 September 2002 Published 25 October 2002 Online at stacks.iop.org/IP/18/R99 Abstract We review theoretical and numerical studies of the inverse problem of electrical impedance tomographywhich seeks the electrical conductivity and permittivity inside a body, given simultaneous measurements of electrical currents and potentials at the boundary. (Some figures in this article are in colour only in the electronic version) 1. Introduction Electrical properties such as the electrical conductivity σ and the electric permittivity , determine the behaviour of materials under the influence of external electric fields. For example, conductive materials have a high electrical conductivity and both direct and alternating currents flow easily through them. Dielectric materials have a large electric permittivity and they allow passage of only alternating electric currents. Let us consider a bounded, simply connected set ⊂ Rd ,ford 2and, at frequency ω, let γ be the complex admittivity function √ γ(x,ω)= σ(x) +iω(x), where i = −1. (1.1) The electrical impedance is the inverse of γ(x) and it measures the ratio between the electric field and the electric current at location x ∈ .Electrical impedance tomography (EIT) is the inverse problem of determining the impedance in the interior of ,givensimultaneous measurements of direct or alternating electric currents and voltages at the boundary ∂. -
Series Impedance and Shunt Admittance Matrices of an Underground Cable System
SERIES IMPEDANCE AND SHUNT ADMITTANCE MATRICES OF AN UNDERGROUND CABLE SYSTEM by Navaratnam Srivallipuranandan B.E.(Hons.), University of Madras, India, 1983 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF APPLIED SCIENCE in THE FACULTY OF GRADUATE STUDIES (Department of Electrical Engineering) We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA, 1986 C Navaratnam Srivallipuranandan, 1986 November 1986 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of The University of British Columbia 1956 Main Mall Vancouver, Canada V6T 1Y3 Date 6 n/8'i} SERIES IMPEDANCE AND SHUNT ADMITTANCE MATRICES OF AN UNDERGROUND CABLE ABSTRACT This thesis describes numerical methods for the: evaluation of the series impedance matrix and shunt admittance matrix of underground cable systems. In the series impedance matrix, the terms most difficult to compute are the internal impedances of tubular conductors and the earth return impedance. The various form u hit- for the interim!' impedance of tubular conductors and for th.: earth return impedance are, therefore, investigated in detail. Also, a more accurate way of evaluating the elements of the admittance matrix with frequency dependence of the complex permittivity is proposed. -
Impedance Matching
Impedance Matching Advanced Energy Industries, Inc. Introduction The plasma industry uses process power over a wide range of frequencies: from DC to several gigahertz. A variety of methods are used to couple the process power into the plasma load, that is, to transform the impedance of the plasma chamber to meet the requirements of the power supply. A plasma can be electrically represented as a diode, a resistor, Table of Contents and a capacitor in parallel, as shown in Figure 1. Transformers 3 Step Up or Step Down? 3 Forward Power, Reflected Power, Load Power 4 Impedance Matching Networks (Tuners) 4 Series Elements 5 Shunt Elements 5 Conversion Between Elements 5 Smith Charts 6 Using Smith Charts 11 Figure 1. Simplified electrical model of plasma ©2020 Advanced Energy Industries, Inc. IMPEDANCE MATCHING Although this is a very simple model, it represents the basic characteristics of a plasma. The diode effects arise from the fact that the electrons can move much faster than the ions (because the electrons are much lighter). The diode effects can cause a lot of harmonics (multiples of the input frequency) to be generated. These effects are dependent on the process and the chamber, and are of secondary concern when designing a matching network. Most AC generators are designed to operate into a 50 Ω load because that is the standard the industry has settled on for measuring and transferring high-frequency electrical power. The function of an impedance matching network, then, is to transform the resistive and capacitive characteristics of the plasma to 50 Ω, thus matching the load impedance to the AC generator’s impedance. -
Nonreciprocal Wavefront Engineering with Time-Modulated Gradient Metasurfaces J
Nonreciprocal Wavefront Engineering with Time-Modulated Gradient Metasurfaces J. W. Zang1,2, D. Correas-Serrano1, J. T. S. Do1, X. Liu1, A. Alvarez-Melcon1,3, J. S. Gomez-Diaz1* 1Department of Electrical and Computer Engineering, University of California Davis One Shields Avenue, Kemper Hall 2039, Davis, CA 95616, USA. 2School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China 3 Universidad Politécnica de Cartagena, 30202 Cartagena, Spain *E-mail: [email protected] We propose a paradigm to realize nonreciprocal wavefront engineering using time-modulated gradient metasurfaces. The essential building block of these surfaces is a subwavelength unit-cell whose reflection coefficient oscillates at low frequency. We demonstrate theoretically and experimentally that such modulation permits tailoring the phase and amplitude of any desired nonlinear harmonic and determines the behavior of all other emerging fields. By appropriately adjusting the phase-delay applied to the modulation of each unit-cell, we realize time-modulated gradient metasurfaces that provide efficient conversion between two desired frequencies and enable nonreciprocity by (i) imposing drastically different phase-gradients during the up/down conversion processes; and (ii) exploiting the interplay between the generation of certain nonlinear surface and propagative waves. To demonstrate the performance and broad reach of the proposed platform, we design and analyze metasurfaces able to implement various functionalities, including beam steering and focusing, while exhibiting strong and angle-insensitive nonreciprocal responses. Our findings open a new direction in the field of gradient metasurfaces, in which wavefront control and magnetic-free nonreciprocity are locally merged to manipulate the scattered fields. 1. Introduction Gradient metasurfaces have enabled the control of electromagnetic waves in ways unreachable with conventional materials, giving rise to arbitrary wavefront shaping in both near- and far-fields [1-6]. -
Phasor Analysis of Circuits
Phasor Analysis of Circuits Concepts Frequency-domain analysis of a circuit is useful in understanding how a single-frequency wave undergoes an amplitude change and phase shift upon passage through the circuit. The concept of impedance or reactance is central to frequency-domain analysis. For a resistor, the impedance is Z ω = R , a real quantity independent of frequency. For capacitors and R ( ) inductors, the impedances are Z ω = − i ωC and Z ω = iω L. In the complex plane C ( ) L ( ) these impedances are represented as the phasors shown below. Im ivL R Re -i/vC These phasors are useful because the voltage across each circuit element is related to the current through the equation V = I Z . For a series circuit where the same current flows through each element, the voltages across each element are proportional to the impedance across that element. Phasor Analysis of the RC Circuit R V V in Z in Vout R C V ZC out The behavior of this RC circuit can be analyzed by treating it as the voltage divider shown at right. The output voltage is then V Z −i ωC out = C = . V Z Z i C R in C + R − ω + The amplitude is then V −i 1 1 out = = = , V −i +ω RC 1+ iω ω 2 in c 1+ ω ω ( c ) 1 where we have defined the corner, or 3dB, frequency as 1 ω = . c RC The phasor picture is useful to determine the phase shift and also to verify low and high frequency behavior. The input voltage is across both the resistor and the capacitor, so it is equal to the vector sum of the resistor and capacitor voltages, while the output voltage is only the voltage across capacitor. -
Analysis of Magnetic Resonance in Metamaterial Structure
Analysis of magnetic resonance in Metamaterial structure Rajni#1, Anupma Marwaha#2 #1 Asstt. Prof. Shaheed Bhagat Singh College of Engg. And Technology,Ferozepur(Pb.)(India), #2 Assoc. Prof., Sant Longowal Institute of Engg. And Technology,Sangrur(Pb.)(India) [email protected] 2 [email protected] Abstract: ‘Metamaterials’ is one of the most 1. Introduction recent topics in several areas of science and technology due to its vast potential in various Metamaterials are artificial materials synthesized applications. These are artificially fabricated by embedding specific inclusions like periodic materials which exhibit negative permittivity structures in host media. These materials have and/or negative permeability. The unusual the unique property of negative permittivity electromagnetic properties of metamaterial and/or negative permeability not encountered in have opened more opportunities for better the nature. If materials have both parameters antenna design to surmount the limitations of negative at the same time, then they exhibit an conventional antennas. Metamaterials have effective negative index of refraction and are created many designs in a broad frequency referred to as Left-Handed Metamaterials spectrum from microwave to millimeter wave (LHM). This name is given to these materials to optical structures. The edifice building because the electric field, magnetic field and the blocks of metamaterials are synthetically wave vector form a left-handed system. These fabricated periodic structures of having materials offer a new dimension to the antenna lattice constants smaller than the wavelength applications. The phase velocity and group of the incident radiation. Thus metamaterial velocity in these materials are anti-parallel to properties can be controlled by the design of each other i.e. -
Electric Currents in Infinite Networks
Electric currents in infinite networks Peter G. Doyle Version dated 25 October 1988 GNU FDL∗ 1 Introduction. In this survey, we will present the basic facts about conduction in infinite networks. This survey is based on the work of Flanders [5, 6], Zemanian [17], and Thomassen [14], who developed the theory of infinite networks from scratch. Here we will show how to get a more complete theory by paralleling the well-developed theory of conduction on open Riemann surfaces. Like Flanders and Thomassen, we will take as a test case for the theory the problem of determining the resistance across an edge of a d-dimensional grid of 1 ohm resistors. (See Figure 1.) We will use our borrowed network theory to unify, clarify and extend their work. 2 The engineers and the grid. Engineers have long known how to compute the resistance across an edge of a d-dimensional grid of 1 ohm resistors using only the principles of symmetry and superposition: Given two adjacent vertices p and q, the resistance across the edge from p to q is the voltage drop along the edge when a 1 amp current is injected at p and withdrawn at q. Whether or not p and q are adjacent, the unit current flow from p to q can be written as the superposition of the unit ∗Copyright (C) 1988 Peter G. Doyle. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, as pub- lished by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. -
Modelling of Anisotropic Electrical Conduction in Layered Structures 3D-Printed with Fused Deposition Modelling
sensors Article Modelling of Anisotropic Electrical Conduction in Layered Structures 3D-Printed with Fused Deposition Modelling Alexander Dijkshoorn 1,* , Martijn Schouten 1 , Stefano Stramigioli 1,2 and Gijs Krijnen 1 1 Robotics and Mechatronics Group (RAM), University of Twente, 7500 AE Enschede, The Netherlands; [email protected] (M.S.); [email protected] (S.S.); [email protected] (G.K.) 2 Biomechatronics and Energy-Efficient Robotics Lab, ITMO University, 197101 Saint Petersburg, Russia * Correspondence: [email protected] Abstract: 3D-printing conductive structures have recently been receiving increased attention, es- pecially in the field of 3D-printed sensors. However, the printing processes introduce anisotropic electrical properties due to the infill and bonding conditions. Insights into the electrical conduction that results from the anisotropic electrical properties are currently limited. Therefore, this research focuses on analytically modeling the electrical conduction. The electrical properties are described as an electrical network with bulk and contact properties in and between neighbouring printed track elements or traxels. The model studies both meandering and open-ended traxels through the application of the corresponding boundary conditions. The model equations are solved as an eigenvalue problem, yielding the voltage, current density, and power dissipation density for every position in every traxel. A simplified analytical example and Finite Element Method simulations verify the model, which depict good correspondence. The main errors found are due to the limitations of the model with regards to 2D-conduction in traxels and neglecting the resistance of meandering Citation: Dijkshoorn, A.; Schouten, ends. Three dimensionless numbers are introduced for the verification and analysis: the anisotropy M.; Stramigioli, S.; Krijnen, G.