...rating of several hundred MVAs are quite common in generating stations. Synchronous generators are the primary energy conversion devices of the world’s electrical power systems today. Because the rotor speed is proportional to the frequency of excitation, synchronous motors can be used in situations where constant speed drive is required. In industry, synchronous motors are used mainly where constant speed is desired. In industrial drivers, therefore synchronous motors are not as widely used as induction or dc motors a linear version of the synchronous motor (LSM) is being considered for high speed transportation systems of the future. An important feature of the synchronous motor is that it can drop either lagging or leading reactive current from the ac supply systems. A synchronous machine is a doubly excited machine. Its rotor poles are excited by a dc current and its starter buildings are connected to the ac supply. The air gap flux is therefore the resultant of the fluxes due to both rotor current and stator current. In a synchronous motor if the rotor field winding provides just the necessary excitation , the stator will draw no reactive current; that is the motor will operate at a unity power factor. If the rotor excitation current is decreased, lagging reactive current will be drawn from the ac source to aid magnetization by tr rotor field current and the machine will...
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...required to operate all of the locomotive systems that we have learned about in the previous modules of this class. It also provides power for some equipment that will be described in this module for the first time. This module will introduce you to the auxiliary power system components and circuits. These include the auxiliary alternator, alternator excitation circuits, the battery charging circuit, and the auxiliary motor supply circuits. Sections Section 1: Auxiliary alternator Section 2: Alternator excitation circuits Section 3: Battery charging circuit Section 4: Auxiliary motor supply – cycle skipper circuits Section 5: Auxiliary motor supply – direct drive circuits Section 6: Auxiliary motor supply – contactor controlled circuits Objectives By the end of this module, you should: • Recognize the auxiliary alternator and understand how it works • Know the components of the traction and auxiliary alternator excitation circuits and understand how they operate • Know the components of the battery charger circuit and understand how they operate • Know the components of the auxiliary motor supply circuits and understand how they operate © 2006 General Electric Company. All rights reserved. The information contained in this document is the property of...
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...f(M) Experiment 7.1 2. Turn on the DC power supply and adjust the value of the rated excitation current according to the machine name plate. Then, start the motor by using the three phase AC power supply. 3. Measure the speed, armature current, excitation current, power factor and input power from 0 N.m until 2.5 N.m, including the rated torque/load value of 1.72 N.m. 4. Then, calculate the output power, reactive power and efficiency based on the measurements. 5. Represent the speed, armature current, power factor, output power and efficiency as functions of torque/load in a single graph and indicate the rated load on the graph. Analysis and Discussions Provide analysis and discussions based on the graph. Instruction Worksheet 3 of 3 Synchronous Motor Load Characteristic n, IL, cos φ, Pout, η = f(M) Experiment 7.2 Objective / Outcome: To determine the load characteristics of a synchronous motor at constant power factor, cos = 1. Procedure: 1. Establish the connections according to the previous diagram. 2. Apply the rated excitation current and start the motor by using the three phase switch. 3. With cos φ = 1, measure the speed, armature current, excitation current and input power from 0 N.m until 2.5 N.m, including the rated torque/load value of 1.72 N.m. TIPS: Since it is difficult to obtain the exact value of cos φ = 1, adjust the excitation current until the power factor swinging...
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...Cardiac Conduction To complete this worksheet, select: Module: Distribution Activity: Animations Title: Cardiac Conduction 1. What is the function of the Conduction System? All cells must contract in a specific sequence. This sequence is determined by the pathway known as the conduction system. 2. Cardiac cells are connective and autorhythmic. What does this mean? Connective cells, action potentials, (excitatory signals) can propagate from one cell to another via gap junctions. Autorhythmic cells can excite themselves spontaneously without stimulation of the nervous system and contract at a regular rhythm. 3. Cells from different parts of the heart’s conduction system have different natural rhythms. What are the average beats per minute at each of the following parts of the heart? a. Sinoatrial Node (SA) 100 bpm b. Atrioventricular Node (AV) 40-50 bpm c. Ventricles 20-40 bpm 4. What is the function of the SA Node? Describe how this happens. The healthy heart’s pacemaker, SA node triggers contraction because it depolarizes at a faster rate than other parts of the conduction system. 5. The AV node starts a series of events that leads to ventricular contraction. Describe this series of events. The AV node is the only connection between the atria and ventricles, once the signal passes the AV node, it propagates through the ventricular...
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...Style Guidelines for Final Year Project ReportsReal Time Implementation of Mixed Excitation Linear Predictive Vocoder Final Year Project Final Report A 4th Year StudentUmer Hamid 06-0063 Faraz Hussain 07-0597 Supervisor: Ms. Durdana Habib Real time optimized Implementation of the Mixed Excitation Linear Predictive Vocoder on the TMS320C6416 DSP [pic] Electrical Engineering Department National University of Computer and Emerging Sciences Islamabad Session 2009-2010 Abstract The purpose of our project is real-time implementation and optimization of a 2.4 Kbps mixed excitation linear prediction (MELP) speech-coding algorithm on a Texas instrument TMS320C64xx digital signal processor. The main emphases of the project is on efficient coding and optimization strategies in computationally intensive modules by exploiting fast L1/L2 memory architecture, 8-parallel data paths, enhanced direct memory access module and instruction set features of TMS320C6000 architecture. The implementation would be based on generic TMS320C6000 DSP series; the optimization techniques aimed are applicable to all types of DSP platforms. Lastly the enhanced DSP/BIOS features were used to implement a real time data handling technique to port the MELP vocoder for real time applications. Contents 1 Introduction 6 1.1 THE MELP SPEECH PRODUCTION MODEL 6 2 Development Process 29 2.1 DSP Architecture...
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...MODERN PRACTICAL GUIDE ON ELECTRICAL MACHINES G.A.N BRIGHT REPORT PRESENTATION 1. Title 2. Aim 3. Apparatus/Equipments 4. Procedure/Method 5. Theory/Results 6. Safety Precaution 7. Conclusion N/B: Safety Precaution must be minimum of four PART 1 SYNCHRONOUS MACHINE 1.1 INTRODUCTION A synchronous machine is an a.c machine in which the rotor moves at a speed which bears a constant relationship to the frequency of currents, in the armature winding. A synchronous machine is one of the important type of electric machines. Large a.c networks operating at constant frequency of 50Hz rely almost exclusively on synchronous generators, also called the alternators, for the supply of electrical energy. Private, stand-by and peak load plants with diesel or gas-turbine prime movers also have synchronous generators. Synchronous motors provide constant speed industrial drives with the possibility of power factor correction. Synchronous machine are generally constructed in larger sizes. Small size alternators are not economical. The modern trend is to build alternators of very large size capable of generating 500MVA or even more. The synchronous motor is rarely built in small sizes owing to superior performance characteristics and economical construction of induction motors. 1.2 OPERATING PRINCIPLE The operating principle of a synchronous machine is fundamentally the same as that of a d.c machine, but, unlike...
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...Research Report 2005-27 Double Side Control of Wound Rotor Induction Machine for Wind Energy Application Employing Half Controlled Converters D. Panda, T. A. Lipo* Rockwell Automation Advanced Technology Lab, Richmond Heights, Ohio 44143, USA, dpanda@ieee. org *Department of Electrical and Computer Engineering University of Wisconsin, Madison, WI 53706, USA, lipo@engr.wisc.edu isconsin lectric achines & ower lectronics onsortium University of Wisconsin-Madison College of Engineering Wisconsin Power Electronics Research Center 2559D Engineering Hall 1415 Engineering Drive Madison WI 53706-1691 © 2005 Confidential Double side control of wound rotor induction machine for wind energy application employing half controlled converters Debiprasad Panda 1, Thomas .A.Lipo 2 Rockwell Automation Advanced Technology Lab, Richmond Heights, Ohio 44143, USA, dpanda@ieee.org 2 Department of Electrical and Computer Engineering University of Wisconsin, Madison, WI 53706, USA, lipo@engr.wisc.edu 1 Abstract – A double side converter fed wound rotor induction machine control for a wind energy application is proposed in this paper. In order to reduce the cost of a wind generator system, a new configuration using half controlled converters for both the stator and rotor circuit as well as for the line side is proposed. The proposed controller reduces the required KVA rating of both machine side and line side converters, improves the efficiency of the wind generator, helps operating...
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...Introduction All system which possessing mass and elasticity are capable of undergoing free vibration. The main interest of such system is the natural frequency of the vibration. Natural frequencies are a function of system stiffness and mass. Generally, all real systems have infinite number of natural frequencies. Resonance, large vibration, will occur in a system when the forcing frequency of the system is equal to one of the natural frequencies. Generally, vibration is a form of wasted energy and normally is undesirable is most cases. It generates noise, instability and will consequently lead to system break down which is a disastrous effect. This project studies a model vibration of a four-cylinder engine which is mounted on a cantilever. This system can be modeled as a mass spring system so that the vibration of the system can be studied. These vibrations are mainly due to the unbalance of primary or secondary forces and couples. 1. Background The model engine consists of four cylinders mounted of a crank shaft with different crank phase angles. A DC motor with a variable speed control drives the shaft and makes the four-cylinder to rotate. The shaft is rotating at a constant angular speed, however, producing an acceleration on the pistons. Hence there are some inertia forces acting on the crank shaft due to these accelerations. The relative crank phase angles of the four cylinders can be adjusted by loosen three Allan screws...
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...higher coil short circuits detection became essential due to the large loss during the possible outage in power supply caused by coil short circuit. Therefore, the purpose of this work is to develop the interturn insulation field winding control procedures using the impulse actions. This method is more efficient comparing to the traditional method, which is associated with the time consumption and application complexity in an emergency. 2. Schematic diagram of the diagnostic tests Schematic diagram of the diagnostic tests for the methods associated with video pulse filing on the excitation winding turbogenerator is shown in (Fig. 1). [pic] Fig.1. Scheme for coil short circuit diagnosis in the winding rotor The impulse impact generator includes low-power DC source UG, allowing you to install the current not more than 10-15 A, capacitor C, connected to the source through the excitation winding; VT - diode, that may influence...
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...Varian Cary Eclipse Spectrofluorometer: (Fluorescence, Phosphorescence, Chemiluminescence) Table of Contents: Chapter 1: Introduction…………………………………………………….3 a. General Characteristics…………………………………………...3 b. Signal Theory…………………………………………………….3/4 c. Sample Type……………………………………………………...5 d. Advantages……………………………………………………….5 e. Disadvantages/Limitations……………………………………….5 Chapter 2: Instrumentation………………………………………………....6 a. Block Diagram…………………………………………………...6/7 b. Internal Design…………………………………………………..6/7 c. External Design…………………………………………………6/7 Chapter 3: Operating Instructions………………………………………….8 a. Start Up/Shut Down…………………………………………......8 b. Precautions…………………………………………………….....8 c. Fluorescence Scan………………………………………………..9 d. Phosphorescence Scan…………………………………………..13 e. Chemiluminescence Scan………………………………………...11 Chapter 4: References……………………………………………………...15 Chapter 1: Introduction a. General Characteristics Varian has been supplying essential tools for scientists engaged in drug discovery, life science, genetic engineering, neuroscience studies, health care, environmental analysis, and academic applications for over 50 years. Cary has been associated with high performance spectrophotometers for over 50 years. The Cary Eclipse Fluorescence spectrophotometer fit well within the Cary range, offering the excellent specifications and modern software that has become the Cary standard. The Spectrophotometer was designed...
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...SYNC shown in denominator in Figure 1. In the prelab: the circuit behavior has to be verified in OrCAD. The maximum clock frequency has to be calculated using timing specs of the flip-flops and multiplexers (logical gates) from datasheet. In the experiment: first, the functionality of the counter has to be tested with a pushbutton that controls the clock and a 7-segment LED display connected to the outputs. Finally, the counter sequence should be demonstrated with the logic analyzer synchronized with SYNC signal, 4inputs of the logic analyzer should be grouped into a bus. 3. Approaches Outputs of four D-flip-flops Q3Q2Q1Q0 serve as outputs of the counter. Next states Q*3Q*2Q*1Q*0 are formed from present states Q3Q2Q1Q0 with combinational excitation circuits. By design we understand determination of the minimal expressions for combinational circuits which excite flip-flop inputs D3, D2, D1, D0. Next states for unused states...
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...The human body is very complex and consists of various anatomical and physiological aspects. One such aspect that makes up the largest group of tissues in the body is muscle (Sherwood, 2013, p. 259). Muscles are identified as either striated or unstriated and either voluntary or involuntary. Of the various types of muscles, skeletal muscle contributes to 40% of the human body weight (Sherwood, 2013, p. 259). Skeletal muscle is controlled by the somatic nervous system, which means that it is a voluntary muscle. When considering appearance, it is a striated muscle meaning to say that it has alternating light and dark bands (Sherwood, 2013, p. 259). Skeletal muscle is made up several muscle fibers in which each muscle fiber consists of myofibrils,...
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...armature currents rotates at the same speed as that created by the field current on the rotor, which is rotating at the synchronous speed, and a steady torque results. Synchronous machines are commonly used as generators especially for large power systems, such as turbine generators and hydroelectric generators in the grid power supply. Because the rotor speed is proportional to the frequency of excitation, synchronous motors can be used in situations where constant speed drive is required. Since the reactive power generated by a synchronous machine can be adjusted by controlling the magnitude of the rotor field current, unloaded synchronous machines are also often installed in power systems solely for power factor correction or for control of reactive kVA flow. Such machines, known as synchronous condensers, may be more economical in the large sizes than static capacitors. With power electronic variable voltage variable frequency (VVVF) power supplies, synchronous motors, especially those with permanent magnet rotors, are widely used for variable speed drives. If the stator excitation of a permanent magnet motor is controlled by its rotor position such that the stator field is always 90o (electrical) ahead of the rotor, the motor performance can be very close to the conventional brushed dc motors, which is very much favored for variable speed drives. The rotor position can be either detected by using rotor position...
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...2 Overview For industrial tomography, the emphasis is usually on high speed data acquisition, rather than resolution. This lends itself to electrical tomography techniques, which although lacking the resolution of x-ray and MRI tomography, are nearly instantaneous. Examples of electrical tomographic imaging methods are Magnetic Induction Tomography (MIT), in which multiple measurements of coupling between magnetic excitation Sensitivity maps reconstruction of Magnetic Induction Tomography real data measurement technique through and sensing coils are used to determine the internal resistivity of an object. Object Image Figure 1.1: Object and imaged with electrical capacitance tomography Sensitivity maps reconstruction of Magnetic Induction Tomography real data measurement technique through 1.2.1 Magnetic Induction Tomography (MIT) Magnetic induction tomography (MIT) is a new and emerging type of tomography technique that is able to map the passive electromagnetic properties (in particular conductivity) of an object. Excitation coils are used to induce eddy currents in the medium, and the...
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... Fig 1. Two machines system When the generator electrical load is suddenly increased, the electrical power exceeds the mechanical power input. This power deficiency is supplied by the kinetic energy stored in the rotating system. The reduction in kinetic energy resulted turbine speed to drop and as well as the frequency of the generator. This change of speed can be adjusted by a governor, which is an attachment to a machine for automatic control or limitation speed; it controls the energy through the prime mover to control its power. Governor changes the input valve to change mechanical power output, thus bringing the speed to a new steady state. Another aspect to be considered in this analysis chapter is the application of the excitation system to the system. The exciter acts as the "backbone" of the generator control system. It is the power source that supplies the dc magnetizing current to the field windings of a...
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