ac power distribution and control

... succeeds and the packet is forwarded on every interface in OIL In our example, OIL for current multicast packet consists of interfaces S2 and E0, so the packet is forwarded on interfaces S2 and E0 ... never in the OIL; therefore, the packet is never forwarded back out of the RPF interface Copyright © 2000, Cisco Systems, Inc IP Multicast Distribution Trees and Control Protocols 2-5 Routers perform ... multicast packets were received via the interface that is on the most direct path to the source that sent the packets In the above example, each router forwards received multicast packets to each of...

Ngày tải lên: 11/12/2013, 14:15

... maintenance practices, including the training and work practices of personnel and the selection and operation of equipment 26 Power Transmission and Distribution THE PRIMARY SYSTEM The primary distribution ... real power to apparent power From Figure 1-5 Power factor = watts = cos θ EI where E = effective voltage, I = effective current, and θ is their angular displacement in phase Figure -5 Power Factor ... required capacity of facilities that would otherwise be required if based on connected loads or the sum of component load demands only Figure 1-3 Diversity Factor Load Factor Demand factors and diversity...

Ngày tải lên: 18/02/2014, 22:20

Ngày tải lên: 05/03/2014, 10:21

... appropriateness of the control sample below For each firm in our main and control samples we collect data on ownership and control The ownership data include the percentage of voting and cash flow (equity) ... are replaced) and of affiliation with a pyramidal business group in the main and control samples The comparison between the main sample and the control group proceeds as follows For each unifying ... this coding system, each firm can score 0, 0.5, or 1, in each year, and the maximal cumulative control change score for each firm is (representing a full control change in each year starting in...

Ngày tải lên: 07/03/2014, 01:20

... and (7) show the system can provide independent active and reactive power control by regulating the rotor current The proposed deadbeat power control, shown in Wireless Coded Deadbeat Power Control ... 3v1 L M and for the reactive power control by using (8) is: i2d (k + 1) = i2dre f = − 2Qre f L1 3v1 L M + λ1 LM (13) where: Pre f is the active power reference and Qre f is the reactive power reference ... power control, as shown in the equations (10) and (11), it is required to calculate the active and reactive power values, their errors, the stator flux magnitude and position, the slip speed and...

Ngày tải lên: 07/03/2014, 11:20

... Preface tion and space vector modulations are analyzed Unity -power factor control and active damping control for the current source rectifiers are also included Part Five, High -Power ac Drives, ... and current ratings Packaging High High Low Press pack Press pack Switching speed Turn-on (di/dt) snubber Turn-off (dv/dt) snubber Active overvoltage clamping Active di/dt and dv/dt control Active ... Simultaneous ␣ and ma Control 232 11.4.3 Power Factor Profile 235 11.5 Active Damping Control 236 11.5.1 Introduction 236 11.5.2 Series and Parallel Resonant Modes 237 11.5.3 Principle of Active Damping...

Ngày tải lên: 16/03/2014, 05:20

... shows a typical power factor correction capacitor switching event 33.3.3 Current Recordings FIGURE 33.5 Typical voltage waveform disturbance caused by power factor correction capacitor energization ... absence of standards, several manufacturers have developed proprietary ‘‘flicker’’ meters In recent years, an effort has been made to standardize the definition of ‘‘flicker,’’ and to standardize the ... examples of disturbance data in books such as The BMI Handbook of Power Signatures, Second Edition, and the Dranetz Field Handbook for Power Quality Analysis ß 2006 by Taylor & Francis Group,...

Ngày tải lên: 21/03/2014, 12:11

... System Modeling and Analysis William H Kersting 22 Power System Operation and Control George L Clark and Simon W Bowen 23 Hard to Find Information (on Distribution System Characteristics and Protection) ... Reactive Power Compensation Rao S Thallam 19 Environmental Impact of Transmission Lines George G Karady IV Distribution Systems 20 Power System Loads Raymond R Shoults and Larry D Swift 21 Distribution ... Utilization—Loads, Load Characterization and Load Modeling Andrew Hanson 27 Electric Power Utilization: Motors Charles A Gross VI Power Quality 28 Introduction S.M Halpin 29 Wiring and Grounding for Power Quality...

Ngày tải lên: 21/03/2014, 12:11

... machine built on Grandpa’s Knob, near Rutland, Vermont, in 1941 This turbine, called the Smith-Putnam machine, had a tower that was 34 m high and a rotor 53 m in diameter The rotor turned an ac ... Oklahoma, and Texas), the winds are strongest in the spring (March and April) and weakest in the summer (July and August) Utilities here are summer peaking, and hence need the most power when ... full-time at peak power They therefore must cut back part of the time because of the lack of water A combination hydro and wind plant can conserve water when the wind is blowing, and use the water...

Ngày tải lên: 21/03/2014, 12:11

... electrochemical reactions take place: an oxidation half-reaction occurring at the anode and a reduction half-reaction occurring at the cathode The anode and the cathode are separated from each other ... battery’s low specific energy and poor energy density make for a very large and heavy battery pack, which cannot power a vehicle as far as an equivalent gas-powered vehicle Lead–acid batteries should ... systems are quiet and non-polluting, and can be installed near load centers and existing suburban substations These have round-trip AC AC efficiencies in the range of 85%, and can respond to...

Ngày tải lên: 21/03/2014, 12:11

... layer and a back contact of an appropriate metal for ohmic contact, such as Au, Cu=Au, Ni, Ni=Al, ZnTe:Cu or (Cu, HgTe) The back contact is then covered with a layer of ethylene vinyl acetate ... their ‘‘speckled’’ surface appearance 3.1.1.3 Thin Silicon (Buried Contact) Cells The current flow direction in most PV cells is between the front surface and the back surface In the thin silicon ... protectors on input and output, ground fault protection circuitry, and maximum power tracking circuitry to ensure that the PV array is loaded at its maximum power point The PCUs act as current sources,...

Ngày tải lên: 21/03/2014, 12:11

... Remedial Action Schemes Individual Unit Control Switchyard, Spillway, Station Service Control and Monitoring Plant Real Power Control and Monitoring Automatic Voltage Control Water and Power Optimization ... Control Pump Storage Control Trashrack Control Forebay Selective Withdrawal Control Black Start Control Unit Auxiliaries Control Governor/Excitation Control/ Status Unit Load Control Unit Annunciation ... Local Control User Interface Station Service Local Control User Interface Spillway Local Control User Interface FIGURE 4.5 Relationship of local, centralized, and off-site control (From IEEE Standard...

Ngày tải lên: 21/03/2014, 12:11

... bars and end connections are required in the pole face to minimize and withstand the high heat of starting duty Direct current excites the rotor windings of salient, and non-salient pole motors and ... were a capacitor Shaft grounding and shaft voltage and grounding current monitoring can be employed to predict and prevent bearing and other problems 5.3 Performance 5.3.1 Synchronous Machines, ... criteria, and the knowledge of the stator current and cooling system effectiveness, the manufacturer can project the motor component heating, and thus insulation life, and the efficiency of the machine...

Ngày tải lên: 21/03/2014, 12:11

... DC Auxiliary Power Systems for Generating Stations Switchgear IEEE Standards Collection: Power and Energy-Switchgear, 1998 Edition Auxiliary Transformers IEEE Distribution, Power and Regulating ... plant and range in size from fractional horsepower to several thousand horsepower These motors may be supplied with the equipment they drive or they may be specified by the electrical engineer and ... and various special function relays 6.13 Maintenance and Testing A good plant design will take into account maintenance and testing requirements Equipment must be accessible for maintenance and...

Ngày tải lên: 21/03/2014, 12:11

... diesel and turbines with mass, and ‘‘self-commutating’’ units which could include microturbines and fuel cells, would require more stringent control packages due to their islanding and reverse power ... capabilities and power density characteristics, although some large battery installations could be used for peak shaving All of the storage technologies have a power electronic converter interface and ... current) with by-products of water, carbon dioxide, and heat The DC power can be used directly or it can be fed to a power conditioner and converted to AC power (see Fig 7.2) DC Current Flow Hydrogen...

Ngày tải lên: 21/03/2014, 12:11

... used voltage control method The capacitor reduces lagging -power- factor reactive power and improves the power factor This increases voltage and reduces current and losses Mechanical and thyristor ... Reactive Power Compensation Rao S Thallam 18-1 The Need for Reactive Power Compensation Application of Shunt Capacitor Banks in Distribution Systems—A Utility Perspective Static VAR Control ... Power System Reliability and Related Space Weather Climatology Geological Risk Factors and Geoelectric Field Response Power Grid Design and Network Topology Risk Factors Extreme Geomagnetic...

Ngày tải lên: 21/03/2014, 12:11

... longitudinal, transverse, and vertical directions, and the structure deterministically designed Using the loads and structure configuration, ground line reactions are calculated and used to accomplish the ... consideration as an International Standard References Carton, T and Peyrot, A., Computer Aided Structural and Geometric Design of Power Lines, IEEE Trans on Power Line Syst., 7(1), 1992 Dreyfuss, ... Valley, Electric Light and Power Magazine, 48(vii), 55–58, 1971 12 Pohlman, J and Lummis, J., Flexible Structures Offer Broken Wire Integrity at Low Cost, Electric Light and Power, 46(V, 144–148.4),...

Ngày tải lên: 21/03/2014, 12:11

... the surface Surface roughness increases and contamination accumulation accelerates aging 15 Erosion is due to discharge-initiated chemical reactions and a rise in local temperature Surface temperature ... brittle fracture Brittle fracture is initiated by the penetration of water containing slight acid from pollution The acid may be produced by electrical discharge and acts as a cathalizator, attacking ... fibers and the resin To improve quality, some manufacturers use E-glass to avoid brittle fractures Brittle fracture can cause sudden shattering of the rod 10.3.1.4 Interfaces Between Shed and Fiberglass...

Ngày tải lên: 21/03/2014, 12:11

... a line worker would have utilized a spacer cart to move out on the line to replace the spacer, or the line would have been lowered and the spacer replaced and the conductor strengthened The obvious ... spacer cart or whether it was physically able to withstand the tensions of lowering it to the ground By utilizing a helicopter and bare-hand work methods, the spacers were able to be replaced and ... at each tower and a helicopter is brought in and attached to a pilot line The ß 2006 by Taylor & Francis Group, LLC helicopter flies along the tower line and slips the pilot line in through each...

Ngày tải lên: 21/03/2014, 12:11