... binary format; a field in the configuration files indicates which format is used A detailed description of the data file format is given in clause 6 3.4 Information file (xxxxxxxx.lNF) The information ... Part 24: Common format for transient data exchange (COMTRADE) for power systems 1 Scope and object This part of IEC 60255 defines a format for files containing transient waveform and event ... d’accompagnement est sous un format ASCII ou binaire Le fichier de configuration est en format ASCII Des informations complémentaires sur le contenu exact et le format du fichier de configuration
Ngày tải lên: 25/12/2013, 10:51
handbook for electrical engineers hu (6)
... constant K is 234.5°C for copper, 242°C for silver-alloyed copper used for hollow conductors, and 225°C for electrical conductivity aluminum Discharge coolant method For directly cooled ... pair of poles for a salient-pole machine; (b) flux form for typical pair of poles (current in field winding only) FIGURE 7-12 (a) Generalized sketch of one pair of poles for cylindrical ... for cylindrical rotor machine; (b) flux form for a typical pair of poles (current in the field winding only) Downloaded from Digital Engineering... the electrical angle between coil halves
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handbook for electrical engineers hu (8)
... applications For example, it is not uncommon for a single step-uptransformer to accommodate multiple hydro generators To maintain fault isolation between genera-tors for such a transformer-sharing ... main step-up transformer Smaller plants may only have provision for switching via a switchyard breaker on the high voltage side of the step-up transformer, the generator and transformerbeing connected ... spillway, etc Bulkhead gate A gate used either for temporary closure of a channel or conduit before dewater-ing it for inspection or maintenance or for closure against flowdewater-ing water Bulkhead
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handbook for electrical engineers (17)
... less than for overhead systems, but the average duration of an underground outage was 58% longer than for an overhead outage. In other words, for Beaty_Sec18.qxd 17/7/06 8:53 PM Page 18-4 Downloaded ... the website. POWER DISTRIBUTION [...]... used for r in Eq (18-2) r ϭ 0.528 !A for 7 strands, r ϭ 0.5585 !A for 19 strands, r ϭ 0.5675 !A for 37 strands, where r ϭ equivalent radius, in, ... equivalent circuit for both the voltage-drop and loss calculations Figure 18-6 shows the FIGURE 18-6 Uniformly distributed loads load representation and equivalent for uniformly distributed
Ngày tải lên: 21/03/2014, 12:12
handbook for electrical engineers (18)
... not exceed 15 A for 14 AWG, 20 A for 12 AWG, and 30 A for 10 AWG copper; or 15 A for 12 AWG and 25 A for 10 AWG aluminum and copper-clad aluminum after any correction factors for ambient temperature ... not exceed 15 A for 14 AWG, 20 A for 12 AWG, and 30 A for 10 AWG copper; or 15 A for 12 AWG and 25 A for 10 AWG aluminum and copper-clad aluminum after any correction factors for ambient temperature ... ceiling electrical service for conductors not larger than No 0AWG, not only for light and power but also for telephone and signal circuits The large internal-cellareas (normally on 6-in centers) afford
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handbook for electrical engineers (19)
... gearless drive system for ball mill Cycloconverter Drive. A unique application for large low-speed synchronous motors is for less ball-mill drives for the cement industry For a recently installed ... FIGURE 20-26 Equivalent circuit for circle diagram. Trang 26TABLE 20-2 Formulas for Calculating Circuit Constants fromTest Data for 3-Phase MotorsX1 X2 0.5X for single squirrel-cage or wound-rotor ... switching is done with a contactor for the slip-ring type, and with thyristors on the rotating rectifier assemblyfor the brushless type Except for the disconnection for starting, the synchronous-motor
Ngày tải lên: 21/03/2014, 12:12
handbook for electrical engineers,(21)
... (e.g.,sinusoidal control voltage or current) Using a stationary to rotating frame transformation, com- monly called the abc to dq transformation, the tracking problem can often be reduced to a regula-tion problem ... signals for the individual switches are derived using q(t) and the circuit topology For the waveforms in Fig 22-22, f s 60Hz and V in 2 kV Since the !3/2 # V in !3/2 # V in y S Trang 28 ANwaveform ... to simplification of control design for flyback converters [5] It should be noted that requirement of electrical isolation is not the only reason that a transformer or(coupled inductor) is used
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handbook for electrical engineers (22)
... higher voltages For delta-connected transformers, ferroresonance can occur for less than 100 ft of cable For this reason, many utilities avoid this connection on cable-fed transformers The grounded ... Unfortunately, this leaves the transformer without any load to damp out the resonance • Phase of a cable connected to a wye-connected transformer Downloaded from Digital... open 23.4.11 Transformer ... than a comparably-sized 15-kV-class transformer Therefore, damaging ferroresonance has been more common at the higher voltages For delta-connected transformers, ferroresonance... apparent), power
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handbook for electrical engineers (24)
... utility industry information system Such a system isshown in Fig 25-1 It depicts a typical information system which may be viewed as a combinationand integration of several functional information systems ... system.Distribution Construction Information System. This application supports the management of newinvestment and maintenance in the distribution area It provides information for planning, schedul-ing, ... control invest-Distribution Facilities Information System. This application provides the information required toplan, control, maintain, locate, account for, and manage the distribution facilities
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handbook for electrical engineers (25)
... technical literature for current mation, and for designations employed with superior-color lamps Special phosphors are also used infor-in fluorescent lamps designed for plant growth and for black-light ... fluorescent lighting Indeed, some electrical engineers specify cableswith single, oversized neutral conductors, cables providing a separate neutral for each phase, trans-formers designed to handle harmonic ... inherent in lamp manufacture and lamp materials make it impossible for each individual lamp to operate for exactly the life for which it was designed A typ-ical mortality curve of a large group
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handbook for electrical engineers (26)
... practical impossibility For this reason, themethods for determining withstand voltage for internal insulation are different Specifically, internal insulation is designed for a specific withstand ... diagram The Bewley diagram provides, for every point in a system, all the waves present and the time at whichthey arrive From this information, the actual voltage waveform at a specific point can be ... and currents gll (y, t) and i gll (y, t) through Karrenbauer’s transformation yields the following transformed equa-tions for the 3-phase line (Meliopoulos 1988) i abc (y, t) Ki gll (y, t)
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handbook for electrical engineers (27)
... safety or performance requirements for products or services, for example, standards for workshoes for those involved in electrical work to be “nonconductive with a reinforced toe” for safety purposes. ... TELECOMMUNICATIONS, AND INFORMATION TECHNOLOGY 28-33 Webpages of Interest to Those Searching for Standards-Related Information NSSN (National Standards System Network) (a free online information service ... ELECTROTECHNOLOGY, TELECOMMUNICATIONS, AND INFORMATION TECHNOLOGY International Information Technology (IT) Standards. When the need for international standards in the field of information technology arose, it
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handbook for electrical engineers
... electric circuit is a collection of electrical devices and components connected together for the purpose of processing information or energy in electrical form An electriccircuit may be described ... Ampere’s law is written first in integral form and then in differential form: (2-38)(2-39) An illustration of Ampere’s law may be seen in Fig 2-19 For more information, please refer to theWeb site ... called ac (for alternating current) sources.Figure 2-24 shows the standard symbol for an ac source The most gen-eral expression for a voltage in sinusoidal form is of the type (2-46)and, for a current
Ngày tải lên: 21/03/2014, 12:12
handbook for electrical engineers chuong (1)
... CONVERSION FACTORSH Wayne Beaty Editor, Standard Handbook for Electrical Engineers; Senior Member, Institute of Electrical and Electronics Engineers, Technical assistance provided by Barry N Taylor, ... entropy heat capacity Trang 6may occur For example, pA is the SI symbol for 10–12of the SI unit for electric current (picoampere),while Pa is the SI symbol for pressure (the pascal).The spelled-out ... expressed in compound form embrac-ing the SI units from which they are derived Examples are the volt per ampere for the ohm, the jouleper second for the watt, the ampere-second for the coulomb, and
Ngày tải lên: 21/03/2014, 12:12
Engineering materials for electrical engineers
... Trang 1ECE 331: Introduction to Materials for Electrical Engineers Course Objective Introduce fundamental concepts in Materials Science and how ... semiconductor devices Trang 2ECE 331 – Intro to Materials for ECEMaterials in ECE are: semiconductors, metals (e.g Al contacts), polymers (e.g encapsulants for LEDs) and insulators (ceramics such as silicon ... Intro to Materials for ECEIII-V examples GaAs InP InAs AlGaAs InGaAs InGaAsP G N InGaN III - V •Know your periodic table! •Find your old chemistry notes! Trang 4Materials Roadmap for Device Technologies:
Ngày tải lên: 24/05/2014, 12:25
handbook for electrical engineers hu (2)
... case. 3.1.8 Instrument Transformers The material that follows is a brief summary of information on instrument transformers as measure- ment elements. For more extensive information, consult American ... instrument transformers, and auxiliary devices. Further detailed information may be found in the Handbook for Electric Metermen, Edison Electric Institute. The practical unit of electrical energy ... instances, the rms value of a voltage or current is required, since the transformation of electrical energy to other forms involves the square of voltages or currents, and the transfer from direct...
Ngày tải lên: 21/03/2014, 12:12
handbook for electrical engineers hu (3)
... mechanical deformation of the alloy takes place at a temperature of about 720°C. Mechanical deformation may be performed by warm extrusion. Magnet size is limited by the amount of deformation needed ... unity for vacuum to slightly greater than unity for gases at atmospheric pressure, 2 to 8 for common insulating solids and liquids, 35 for ethyl alcohol and 91 for pure water, and 1000 to 10,000 for ... Fire-refined copper is a lower-purity grade intended for alloying or for fabrication into products for mechanical purposes; it is not intended for electrical purposes. Casting copper is the grade...
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handbook for electrical engineers hu (4)
... removal of modules, and calibration. Information Readout. The system readouts are to be designed to provide operators with accu- rate, complete, and timely information. Consideration must be given ... produced for further fission action. For a 1300-MW (electrical) light-water nuclear plant, a representative core assembly might involve 241 fuel assemblies each weighing approxi- mately 660 kg, for ... the average lifetime of the neutrons. Substituting for k inf and D gives Substituting 1/ for Σ ␣ (1 ϩ L 2 B 2 ) gives The balance equation for the delayed group is (5-14) Substituting gives and...
Ngày tải lên: 21/03/2014, 12:12
handbook for electrical engineers hu (5)
... HANDBOOK FOR ELECTRICAL ENGINEERS PRIME MOVERS 6-17 to h 1 − h 2 minus the small pump work h 4 – h 3 ϭ 3 (P 4 – P 3 )/J required, and the heat added to the cycle is equal to h 1 – h 4 . Therefore (6-4) ... stainless steels. The rotor may be a single forging, fabricated from a shaft and separate wheels, or constructed of forged elements welded together. The buckets forming the rotating portion of the steam ... a high-pressure hydraulic system to provide the force required. FIGURE 6-7 Mechanical governor for small turbines. Beaty_Sec06.qxd 17/7/06 8:31 PM Page 6-11 Downloaded from Digital Engineering Library...
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handbook for electrical engineers hu (7)
... poles. The oiling system for the bearings should be checked and the oil rings tested for freedom. The entire machine, particularly its air gaps, should be inspected for foreign material. Running ... coil equal to 1 V for a change of 10 8 linkages/s (Mx/s) for each turn of the coil, or E ϭ (⌬fT ϫ 10 –8 )/t V. If the flux lines are deformed by the motion of the coil conductor before they are broken, ... Institute (ANSI) C50.4 for dc machines includes lists of recommended tests for dc generators and motors. The IEEE Test Code for dc machines covers recommended methods to be used for these tests. 8.14...
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