1、 IEEE Guide for Identifying and Improving Voltage Quality in Power Systems Sponsored by the Transmission and Distribution Committee IEEE 3 Park Avenue New York, NY 10016-5997 USA 31 March 2011 IEEE Power +1 978 750 8400. Permission to photocopy portions of any individual standard for educational cla
2、ssroom use can also be obtained through the Copyright Clearance Center. iv Copyright 2011 IEEE. All rights reserved. Introduction This introduction is not part of IEEE Std 1250-2011, IEEE Guide for Identifying and Improving Voltage Quality in Power Systems. This guide was developed out of an increas
3、ing awareness of the incompatibility of some modern electronics equipment with a normal power system environment. Simply put, much new user equipment is not designed to withstand the surges, faults, distortion, and reclosing duty present on typical electric utility distribution systems or within the
4、 users facility. Notice to users Laws and regulations Users of these documents should consult all applicable laws and regulations. Compliance with the provisions of this guide does not imply compliance to any applicable regulatory requirements. Implementers of the guide are responsible for observing
5、 or referring to the applicable regulatory requirements. IEEE does not, by the publication of its standards, intend to urge action that is not in compliance with applicable laws, and these documents may not be construed as doing so. Copyrights This document is copyrighted by the IEEE. It is made ava
6、ilable for a wide variety of both public and private uses. These include both use, by reference, in laws and regulations, and use in private self-regulation, standardization, and the promotion of engineering practices and methods. By making this document available for use and adoption by public auth
7、orities and private users, the IEEE does not waive any rights in copyright to this document. Updating of IEEE documents Users of IEEE standards should be aware that these documents may be superseded at any time by the issuance of new editions or may be amended from time to time through the issuance
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9、ed through the issuance of amendments, corrigenda, or errata, visit the IEEE Standards Association web site at http:/ieeexplore.ieee.org/xpl/standards.jsp, or contact the IEEE at the address listed previously. For more information about the IEEE Standards Association or the IEEE standards developmen
10、t process, visit the IEEE-SA web site at http:/standards.ieee.org. Errata Errata, if any, for this and all other standards can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/updates/errata/index.html. Users are encouraged to check this URL for errata periodically. v Copyrigh
11、t 2011 IEEE. All rights reserved. Interpretations Current interpretations can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/interp/ index.html. Patents Attention is called to the possibility that implementation of thisguide may require use of subject matter covered by paten
12、t rights. By publication of thisguide, no position is taken with respect to the existence or validity of any patent rights in connection therewith. The IEEE is not responsible for identifying Essential Patent Claims for which a license may be required, for conducting inquiries into the legal validit
13、y or scope of Patents Claims or determining whether any licensing terms or conditions provided in connection with submission of a Letter of Assurance, if any, or in any licensing agreements are reasonable or non-discriminatory. Users of thisguide are expressly advised that determination of the valid
14、ity of any patent rights, and the risk of infringement of such rights, is entirely their own responsibility. Further information may be obtained from the IEEE Standards Association. vi Copyright 2011 IEEE. All rights reserved. Participants At the time this guide was submitted to the IEEE-SA Standard
15、s Board for approval, the Voltage Quality Working Group had the following membership: Dennis Hansen, Chair Russ Ehrlich, Vice Chair Fred Hensley, Secretary Adeoti Adediran Art Arneson Richard Bingham Math Bollen Reuben Burch Gary Chang Randy Collins Bill Garlatz Erich Gunther Mark Halpin Paul Hodges
16、 Randy Horton Bill Howe John Kennedy Albert Keri Scott Lacy Kevin Little David Luprek Mark McGranaghan Bill Moncrief David Mueller Marty Page Dean Philips Paulo Ribeiro Dan Sabin Andrew Sagl Bob Saint Kenneth Sedziol Mark Stephens Michael Swearingen Rao Thallam Timothy Unruh James Wikston Charles Wi
17、lliams Brian Wong The following members of the balloting committee voted on this guide. Balloters may have voted for approval, disapproval, or abstention. William J. Ackerman Ali Al Awazi G. Bartok Richard Bingham Oscar Bolado Chris Brooks Gustavo Brunello William Byrd Terry Chapman Arvind K. Chaudh
18、ary James Cleary Michael Coddington Terry Conrad Luis Coronado Alireza Daneshpooy Gary Donner Randall Dotson Michael Doyle Donald Dunn Gearold O. H. Eidhin Gary Engmann Fredric Friend Waymon Goch Edwin Goodwin Thomas Grebe Randall Groves Donald Hall Daryl Hallmark Dennis Hansen Jeffrey Hauber Lee He
19、rron Werner Hoelzl E. Horgan Innocent Kamwa Yuri Khersonsky James Kinney Joseph L. Koepfinger Jim Kulchisky Saumen Kundu Chung-Yiu Lam Greg Luri Jerry Murphy Michael S. Newman Joe Nims Carl Orde Lorraine Padden Bansi Patel M. Pehosh Percy Pool Ulrich Pohl Iulian Profir Michael Roberts Charles Rogers
20、 Thomas Rozek D. Daniel Sabin Bob Saint Bartien Sayogo Kenneth Sedziol Suresh Shrimavle Gil Shultz James Smith Jerry Smith Aaron Snyder John Spare Gary Stoedter K. Stump Michael Swearingen John M. Teixeira John Toth Joe Uchiyama Eric Udren Timothy Unruh Raul Velazquez John Vergis Ilia Voloh Carl Wal
21、l William H. Walter John Wang Daniel Ward Lee Welch Charles Williams Larry Young Xi Zhuvii Copyright 2011 IEEE. All rights reserved. When the IEEE-SA Standards Board approved this standard on 31 March 2011, it had the following membership: Richard H. Hulett, Chair John Kulick, Vice Chair Robert Grow
22、, Past Chair Judith Gorman, Secretary Masayuki Ariyoshi William Bartley Ted Burse Clint Chaplin Wael Diab Jean-Philippe Faure Alex Gelman Paul Houz Jim Hughes David Law Thomas Lee Hung Ling Oleg Logvinov Ted Olsen Gary Robinson Jon Rosdahl Sam Sciacca Mike Seavey Curtis Siller Phil Winston Howard Wo
23、lfman Don Wright *Member Emeritus Also included are the following nonvoting IEEE-SA Standards Board liaisons: Satish Aggarwal, NRC Representative Richard DeBlasio, DOE Representative Michael Janezic, NIST Representative Don Messina IEEE Standards Program Manager, Document Development Matthew J. Cegl
24、ia IEEE Standards Program Manager, Technical Program Development viii Copyright 2011 IEEE. All rights reserved. Contents 1. Overview 1 1.1 Scope . 1 1.2 Purpose 1 2. The power system . 1 2.1 Introduction . 1 2.2 Overview of power systems . 2 3. Identifying voltage quality in power systems . 5 3.1 In
25、troduction . 5 3.2 Basic types of voltage quality variations . 5 3.3 Steady-state (continuous) voltage quality characteristics 6 3.4 Disturbances 20 3.5 Conclusions . 25 4. Electric utilities and voltage quality . 25 4.1 Introduction . 25 4.2 Steady-state voltage quality in utilities 25 4.3 Utility
26、system disturbances 28 4.4 Conclusions . 30 5. Susceptibility of power system loads . 31 5.1 Types of susceptible loads . 31 5.2 Ride-through capability . 33 6. Power quality improvements for end users 34 6.1 End user wiring and grounding 34 6.2 Premium power solutions 35 6.3 End-user power conditio
27、ning (within the facility) . 37 6.4 Controlling harmonics . 44 6.5 Surge protective devices (SPDs) 46 6.6 Special considerations for variable frequency drives (VFDs) . 46 6.7 Special considerations for residential loads . 47 6.8 Economic analysis of power conditioning alternatives 47 Annex A (inform
28、ative) Glossary 49 Annex B (informative) Bibliography 52 1 Copyright 2011 IEEE. All rights reserved. IEEE Guide for Identifying and Improving Voltage Quality in Power Systems IMPORTANT NOTICE: This standard is not intended to assure safety, security, health, or environmental protection. Implementers
29、 of the standard are responsible for determining appropriate safety, security, environmental, and health practices or regulatory requirements. This IEEE document is made available for use subject to important notices and legal disclaimers. These notices and disclaimers appear in all publications con
30、taining this document and may be found under the heading “Important Notice” or “Important Notices and Disclaimers Concerning IEEE Documents.” They can also be obtained on request from IEEE or viewed at http:/standards.ieee.org/IPR/disclaimers.html. 1. Overview 1.1 Scope The reader of this guide will
31、 find discussions of ways to identify and improve voltage quality in power systems, as well as references to publications in this area. More specifically, this guide includes: a) Voltage quality levels from benchmarking studies b) Factors that affect power system performance c) Mitigation measures t
32、hat improve power system performance d) References to current relevant in-depth IEEE standards and other documents This guide only addresses subjects in depth where no other power quality reference does so. It is a “gateway” document for power quality that points the way to other documents in this f
33、ield. 1.2 Purpose The primary purpose in writing this guide is to assist power delivery system designers and operators in delivering power with voltage quality that is compatible with electrical end-use equipment. Another purpose is to point utility system customers toward power quality solutions th
34、at may exist in the power utilization system and equipment. 2. The power system 2.1 Introduction This subclause describes typical utility power systems. Understanding the basics of power system design and operation is helpful in understanding the voltage quality characteristics described in Clause 3
35、. Voltage IEEE Std 1250-2011 IEEE Guide for Identifying and Improving Voltage Quality in Power Systems 2 Copyright 2011 IEEE. All rights reserved. quality characteristics can be affected at various levels of a power system. Electricity is typically generated and delivered at either 50 Hz or 60 Hz. 2
36、.2 Overview of power systems Power systems are usually thought of as having three main divisions: generation, transmission, and distribution. Figure 1 is an oversimplified diagram of a typical U.S. electric power system. In reality, there are many exceptions such as the fact that some large industri
37、al customers are actually served by substations directly from the transmission system and some small generators may feed directly into the distribution system. Figure 1The electric power system Interconnection of the generation, transmission, and distribution systems takes place in an electrical sub
38、station. Substations may include transformers that raise or lower the voltage depending on the need. A substation that has a step-up transformer increases the voltage while decreasing the current, whereas a step-down transformer decreases the voltage while increasing the current for distribution. El
39、ectric power may flow through several substations between generating plants and consumers, and it may be changed in voltage several times. IEEE Std 1250-2011 IEEE Guide for Identifying and Improving Voltage Quality in Power Systems 3 Copyright 2011 IEEE. All rights reserved. The generation and trans
40、mission components are typically connected in an interconnected grid fashion. Within the “grid,” the transmission lines transport bulk power for long distances that typically cross multiple service territories and multiple utilities. Figure 2 shows a simple transmission system, referred to as a tran
41、smission network, illustrating how most of the substation buses have more than one source. In most circumstances, the loss of a single line or generator should not cause overloads within the remaining network. This offers a high degree of reliability because power can be maintained to most buses eve
42、n with the loss of a line or source. Figure 2Transmission network showing generators, substations, and line sections Distribution lines (commonly called primaries) are usually not interconnected but are designed in a radial fashion except in some cities that use a mesh distribution scheme. Radial di
43、stribution systems consist of a source originating at a substation in which the system voltage is stepped down (Figure 3). The distribution bus has breakers that feed lines (feeders) that carry the power to many customers in an area. There are usually line protective components (reclosers and fuses)
44、 downstream of the substation breaker on distribution lines. These components create situations in which only a portion of the distribution line may need to be de-energized to clear a fault (short circuit), thereby saving many customers on the line from experiencing interruptions unnecessarily. IEEE
45、 Std 1250-2011 IEEE Guide for Identifying and Improving Voltage Quality in Power Systems 4 Copyright 2011 IEEE. All rights reserved. Figure 3Distribution substation and example of recloser and fuses along line Power system voltages are typically expressed in line-to-line kV. The line-to-line voltage
46、 is 1.732 times the line-to-neutral voltage on wye systems. Practically all generation and transmission is three phase. Distribution lines typically leave the substation as three phase and may proceed that way for several miles. But they may also have lateral tap lines that are only providing two ph
47、ases or even a single phase, depending on the loads being served. Electrical services to customers may be from the transmission or the distribution system. Table 1 describes the various components and typical voltage ranges of the utility system. IEEE Std 1250-2011 IEEE Guide for Identifying and Imp
48、roving Voltage Quality in Power Systems 5 Copyright 2011 IEEE. All rights reserved. Table 1 Common parts of the power system Generation Converts sources of energy such as fuel, falling water, or nuclear material to electricity. Transmission Bulk power transport connecting generating stations to subs
49、tations serving load areas. Generally 230 kV to 765 kV. Long lines with few, if any, taps or customer connections. May be overhead or underground; underground circuits are short because of charging current limitations. Loading limits for lines and loading areas including normal, long-term emergency, and short-term emergency limits. Loading may be limited by system stability, voltage control, or conductor temperature. Loading follows a cycle with time of day, season, and weather. Subtransmission Not distinguished in many systems; lower level bulk power connect
