On utility distribution feeders in Software

Print PDF 417 in Software On utility distribution feeders

631 On utility distribution feeders
Make PDF 417 In None
Using Barcode creator for Software Control to generate, create PDF 417 image in Software applications.
Scan PDF 417 In None
Using Barcode decoder for Software Control to read, scan read, scan image in Software applications.
The X/R ratio of a utility distribution feeder is generally low Therefore, the magnification of harmonics by resonance with feeder banks is usually minor in comparison to what might be found inside an industrial facility Utility distribution engineers are accustomed to placing feeder banks where they are needed without concern about harmonics However, voltage distortion from the resonance of feeder banks may exceed limits in a few cases and require mitigation When problems do occur, the usual strategy is to first attempt a solution by moving the offending bank or changing the capacitor size or neutral connection Some harmonic problems associated with feeder capacitor banks are due to increasing the triplen harmonics in the neutral circuit of the feeder To change the flow of zero-sequence harmonic currents, changes are made to the neutral connection of wye-connected banks To block the flow, the neutral is allowed to float In other cases, it is more advan-
Generating PDF417 In C#
Using Barcode generator for Visual Studio .NET Control to generate, create PDF417 image in .NET framework applications.
PDF417 Maker In VS .NET
Using Barcode printer for ASP.NET Control to generate, create PDF 417 image in ASP.NET applications.
Downloaded from Digital Engineering Library @ McGraw-Hill (wwwdigitalengineeringlibrarycom) Copyright 2004 The McGraw-Hill Companies All rights reserved Any use is subject to the Terms of Use as given at the website
Creating PDF-417 2d Barcode In .NET Framework
Using Barcode creator for .NET Control to generate, create PDF-417 2d barcode image in VS .NET applications.
PDF 417 Generator In VB.NET
Using Barcode printer for Visual Studio .NET Control to generate, create PDF 417 image in .NET framework applications.
Applied Harmonics 236 Six
Barcode Drawer In None
Using Barcode drawer for Software Control to generate, create barcode image in Software applications.
Generate EAN / UCC - 14 In None
Using Barcode encoder for Software Control to generate, create GS1-128 image in Software applications.
tageous to aid the flow by putting a reactor in the neutral to convert the bank into a tuned resonant shunt for a zero-sequence harmonic Harmonic problems on distribution feeders often exist only at light load The voltage rises, causing the distribution transformers to produce more harmonic currents and there is less load to damp out resonance Switching the capacitors off at this time frequently solves the problem Should harmonic currents from widely dispersed sources require filtering on distribution feeders, the general idea is to distribute a few filters toward the ends of the feeder While this is not done frequently, the number of feeder filter installations is growing Figure 63 shows one example of a filter installed on an overhead distribution feeder This shortens the average path for the harmonic currents, reducing the opportunity for telephone interference and reducing the harmonic voltage drop in the lines The filters appear as nearly a short circuit to at least one harmonic component This keeps the voltage distortion on the feeder to a minimum With the ends of the feeder nailed down by filters with respect to the voltage distortion, it is more difficult for the voltage distortion to rise above limits elsewhere Harmonic flow studies should always be performed when large capacitor banks are installed in distribution substations One cannot count on system losses to damp out resonance at this point on the system, and magnification by resonance can be severe
Making GTIN - 13 In None
Using Barcode printer for Software Control to generate, create EAN 13 image in Software applications.
Generating Bar Code In None
Using Barcode creation for Software Control to generate, create barcode image in Software applications.
Figure 63 Filter installation on an overhead distribution feeder Oil-insulated, iron-core reactors are mounted on a separate pole from the capacitor bank and switches (Courtesy of Gilbert Electrical Systems)
Data Matrix Creator In None
Using Barcode printer for Software Control to generate, create DataMatrix image in Software applications.
Code-39 Creation In None
Using Barcode creation for Software Control to generate, create Code39 image in Software applications.
Downloaded from Digital Engineering Library @ McGraw-Hill (wwwdigitalengineeringlibrarycom) Copyright 2004 The McGraw-Hill Companies All rights reserved Any use is subject to the Terms of Use as given at the website
Generate ISBN - 10 In None
Using Barcode maker for Software Control to generate, create ISBN image in Software applications.
Code 39 Full ASCII Generation In None
Using Barcode generation for Font Control to generate, create Code 39 image in Font applications.
Applied Harmonics Applied Harmonics 237
Code 3/9 Reader In Visual C#
Using Barcode scanner for Visual Studio .NET Control to read, scan read, scan image in VS .NET applications.
Scanning Code 128C In .NET Framework
Using Barcode scanner for VS .NET Control to read, scan read, scan image in VS .NET applications.
632 In end-user facilities
UPC Code Recognizer In Visual C#.NET
Using Barcode scanner for .NET Control to read, scan read, scan image in .NET framework applications.
EAN-13 Drawer In None
Using Barcode drawer for Office Excel Control to generate, create GS1 - 13 image in Microsoft Excel applications.
When harmonic problems arise in an end-user facility, the first step is to determine if the main cause is resonance with power factor capacitors in the facility When it is, first attempt a simple solution by using a different capacitor size With automatic power factor controllers, it may be possible to select a control scheme that avoids the configuration that causes problems In other cases, there will be so many capacitors switched at random with loads that it will be impossible to avoid resonant conditions Filtering will be necessary Installation of filters on end-user low-voltage systems is generally more practical and economical than on utility distribution systems The criteria for filter installation are more easily met, and filtering equipment is more readily available on the market When the magnitude of harmonic currents injected by loads is excessive, industrial users should also investigate means of reducing harmonics by using different transformer connections and line chokes In office buildings, zigzag transformers and triplen harmonic filters can reduce the impact of triplen harmonic currents on neutral circuits Studies should be performed on all capacitors installed on the main bus in industrial systems At this location, there are insufficient line losses to dampen resonance Thus, when resonance coincides with a harmonic frequency that is a strong component in the load current, the resulting voltage distortion is often severe Resonance problems are often less severe when capacitors are located out on the plant floor on motors and in motor control centers This also has the benefit of reducing the losses in the system compared to simply placing the capacitor on the main bus Of course, this solution can be more costly than use of a single capacitor on the main bus due to the numerous installations required This assumes that the cables are sufficiently long to introduce enough resistance into the circuit to dampen the resonance In plants with short cables, it may not be possible to achieve significant harmonic reduction benefit 64 Harmonic Studies Harmonic studies play an important role in characterizing and understanding the extent of harmonic problems Harmonic studies are often performed when 1 Finding a solution to an existing harmonic problem 2 Installing large capacitor banks on utility distribution systems or industrial power systems 3 Installing large nonlinear devices or loads
Barcode Maker In Java
Using Barcode generator for BIRT Control to generate, create barcode image in Eclipse BIRT applications.
GTIN - 12 Maker In VB.NET
Using Barcode encoder for .NET framework Control to generate, create GS1 - 12 image in Visual Studio .NET applications.
Downloaded from Digital Engineering Library @ McGraw-Hill (wwwdigitalengineeringlibrarycom) Copyright 2004 The McGraw-Hill Companies All rights reserved Any use is subject to the Terms of Use as given at the website
Copyright © OnBarcode.com . All rights reserved.