Electric Power System Reliability -2007
(including a summary of the 2007 NERC Reliability Standards and an OPS-X™ Simulator Training Exercise)
William H. Smith, P.E.
Powersmiths International is recognized by the North American Electric Reliability
Council as a continuing education provider that adheres to NERC Continuing
Education Program Criteria.
Cover by Rondee Wood
Contents
Preface iv
Introduction 1
Chapter 1. Resource and Demand Balancing 13
NERC Standards BAL-001, 003, 004, 005, 006
Chapter 2. Voltage Control and Reactive Power 35
NERC Standard VAR-001
Chapter 3. Power System Disturbance and Contingency Response 53
NERC Standard BAL-002
Chapter 4. Reliability Operating Limits and Reliability Coordination 65
NERC Standards IRO-004, 005, TOP-004, 007, 008
IRO-001, 002, 003, 014, 015, 016
Chapter 5. Transmission Congestion 89
NERC Standards IRO-006,
FAC- 005, 008, 009, 012, 013, MOD-001 thru 009
Chapter 6. Emergency Operations 115 NERC Standards EOP-001 thru 004
Chapter 7. Power System Restoration 127
NERC Standards EOP-005 thru 009
Chapter 8. Transmission System Operations 159
NERC Standards TOP-001, 002, 003, 005, 006
PRC-001 thru 022
Chapter 9. Interchange 195
NERC Standards INT-001 thru 010
Chapter 10. Transmission Planning 217
NERC Standards TPL-001 thru 006
Chapter 11. Cyber Infrastructure 243
NERC Standards CIP-001 thru 009
Chapter 12. Communications 263
NERC Standards COM-001, 002
Chapter 13. Personnel Performance, Training and Qualifications 267
NERC Standards PER-001 thru 004
Chapter 14. Facilities Design, Connections and Maintenance 273
NERC Standards FAC-001, 002, 003
Chapter 15. Power System Stability 281
Chapter 16. Power System Simulation 287
OPS-X Power System Simulator CD Insert
Answers to Questions 296
About the Author 297
Preface
Electric Power System Reliability-2007 will serve as an aid for those preparing for the NERC System Operator Certification exams and those seeking to familiarize themselves with the power system fundamentals necessary to fully understand and properly implement the NERC Reliability Standards.
This book is a summary of the NERC Reliability Standards to be effective in 2007 presented in the context of power system fundamentals, the understanding of which is required to properly implement those Standards.
The NERC Approved Reliability Standards are organized into fourteen topical blocks on the NERC website:
BAL—Resource and Demand Balancing
CIP—Critical Infrastructure Protection
COM—Communications
EOP—Emergency Preparedness and Operations
FAC—Facilities Design, Connections and Maintenance
INT—Interchange Scheduling and Coordination
IRO—Interconnection Reliability Operations and Coordination
MOD—Modeling, Data, and Analysis
ORG—Organization Certification
PER—Personnel Performance, Training and Qualifications
PRC—Protection and Control
TOP—Transmission Operations
TPL—Transmission Planning
VAR—Voltage and Reactive
This book is organized in sixteen chapters each addressing a fundamental of Power System Reliability. Rather than present the Reliability Standards strictly in the NERC alphabetic Standards blocks, the Standards are presented in the context of the appropriate power system fundamentals. This organization is designed to provide the technical information required to understand the Standards and provide relevance and perspective to highlight the purpose of each Standard or group of Standards. This presentation format is designed to frame each group of standards so that information can be more easily assimilated and retained by electric power system operating personnel.
Each chapter is designed around a fundamental of Power System Reliability and its associated NERC Standards. Background information is presented to explain the purpose, intent and technical relevance of the Standards in that group. Key requirements of the Standards are summarized. Finally, any remaining requirements from the Standards group are presented for completeness.
“Electric Power System Reliability-2006” was first offered in July, 2006. It was popular and served its purpose. For that reason I have not attempted to make major changes. “EPSR-2007” is an updated version of the 2006 book including the new and revised NERC Standards and some new questions to promote understanding.
This book is not intended as a complete and comprehensive representation of the NERC Reliability Standards. Power system professionals should continue to consult the NERC web site and other NERC publications for a comprehensive and current statement of NERC Reliability Standards and their requirements, measures and compliance levels.
vi
Introduction
Introduction
Background
The people of the United States and Canada were first introduced to the notion of electric power system reliability on November 9, 1965. On this date 30 million people in New York, New England and Eastern Canada were without power for up to 13 hours. The outage took months to investigate and eventually the cause was linked to relay settings. It was a classic case of a cascading or “domino effect” blackout. Complete system separation took about 7 seconds.
Since that time there have been at least six major cascading blackouts in North America depending upon the criteria for a “major blackout”. The most recent was August 14, 2003 when 50 million people in portions of New York, Pennsylvania, Ohio, Michigan and Canada were without power for extended periods of time.
Following the 1965 blackout, the North American Electric Reliability Council (NERC) was formed as a voluntary organization of the electric utilities of the United States and Canada.
Some of its activities are to:
• Set standards for the reliable operation and planning of the bulk electric system
• Monitor, assess and enforce compliance with standards for bulk electric system reliability
• Provide educational and training resources to promote bulk electric system reliability
• Assess, analyze and report on bulk electric system adequacy and performance
• Certify reliability service organizations and personnel
Since its inception in 1968, NERC has changed dramatically. It now is comprised of all segments of the electric industry.
• End-use customers
• Investor-owned utilities
• Federal power agencies
• Rural electric cooperatives
• State, municipal and provincial utilities
• Independent power producers
• Power marketers
Through the enactment of the Energy Policy Act of 2005, Congress created Section 215 of the Federal Power Act (FPA). Section 215 assigns to the Federal Energy Regulatory Commission (FERC or Commission) the responsibility and authority for overseeing the reliability of the bulk power systems in the United States, including the setting and enforcement of mandatory reliability standards. In February 2006, the Commission issued Order No. 672 establishing its requirements for certifying an industry self-regulating electric reliability organization (ERO), as envisioned in the legislation. On the basis of that Order, NERC filed its application to become the ERO in the United States on April 4, 2006. NERC concurrently filed for similar recognition with the federal and provincial governments in Canada.
On July 20, 2006 the Commission issued its Order Certifying NERC as the Electric Reliability Organization (ERO) and Ordering Compliance Filing, finding that NERC met the requirements of Order No. 672. In issuing the Order, the Commission directed NERC to provide additional information and file specific revisions to its rules within 90 days, which NERC has done.
On September 15, 2006 the National Energy Board of Canada announced a memorandum of understanding recognizing NERC as the ERO in Canada. NERC continues to work toward establishing a framework for the ERO in each province.
The Elements of Electric Power Systems
While many lessons have been learned since 1965 we continue to have blackouts. Power system loads continue to grow in size and complexity. Reliability expectations continue to rise. Power systems themselves become larger and more complex in response to growing load and customer expectations. Power systems become more difficult to analyze and operate.
In response, we continue to develop new control systems, power system operator training improves each year and through the evolution of NERC and the generation and transmission operating entity organizations, reliability is continually managed to meet growing systems and customer expectations.
The broad topic of Electric Power Systems can be presented in a discussion of its three basic elements: Power System Operations, Power System Economics and Power System Engineering. Each of these is relatively independent of the other except to the extent that they can create physical or practical limits or bounds on each other. Power system engineering must deal with the irrefutable laws of physics. While practically any type of system can be engineered to accomplish the goal of lighting the light bulb, there are the practical limits of costs and the complexity of operation.
Until 1965, the business of providing electric power was somewhat simplistic. That all changed when in one night we all realized how much our lives, economy, public safety and national defense had come to rely on electric power. With this “reliance” came the need for reliability and with reliability came the intersection of the elements of Operations, Engineering and Economics.
Operations, Engineering and Economics are related to the extent that they affect reliability. Before 1965, reliability was an outcome of somewhat independent operational, engineering and economic decisions. After 1965, reliability considerations became a major driver of coordinated operational, engineering and economic decisions. And in the 1970’s environmental considerations joined these elements as a driver of reliability considerations.
The System Planning function within most utilities became the coordinating body for developing reliability criteria and analyzing their impacts on system economics, engineering, environmental concerns and operations. The planning function developed detailed computer operational and economic models to show the performance and costs of various system configurations. Planners were tasked with making power systems reliable, environmental sound and economic. At times these objectives were found to be mutually exclusive. Making a power system economic can negatively impact reliability. Reliability comes with a cost. Power system planners had to exercise judgment and trade off these factors to meet cost, environmental and reliability objectives.
In this book, we will focus on the topic of Electric Power System Reliability or from this point forward simply “Reliability.” We will discuss how reliability requirements radiate out to impact economics, engineering, environmental considerations and operations.
NERC Reliability Initiatives
We have chosen to discuss Reliability not in the abstract or in an academic or probabilistic fashion but in the context of NERC and its primary responsibility for Reliability in North America.
Functional Model
NERC’s Reliability Initiatives emanate from its Functional Model. The following Introduction, Diagram, Purpose and Guiding Principles have been excerpted from the NERC Reliability Functional Model Version 3 document found on the NERC website.
NERC Functional Model Version 3
(excerpted from NERC Functional Model Document )
Foreword
This document replaces version 2 of the NERC Reliability Functional Model that the Board
of Trustees approved on February 10, 2004.
Historically, Control Areas were established by vertically integrated utilities to operate their
individual power systems in a secure and reliable manner and provide for their customers’
electricity needs. The traditional Control Area operator balanced its load with its generation,
implemented interchange schedules with other Control Areas, and ensured transmission
reliability.
As utilities began to provide transmission service to other entities, the Control Area also
began to perform the function of Transmission Service Provider through tariffs or other
arrangements. NERC’s Operating Policies reflected this traditional electric utility industry
structure, and ascribed virtually every reliability function to the Control Area.
Beginning in the early 1990s with the advent of open transmission access and restructuring
of the electric utility industry to facilitate the operation of wholesale power markets, the
functions performed by Control Areas began to change to reflect the newly emerging
industry structure. These changes occurred because:
1. Some utilities were separating their transmission from their merchant functions
(functional unbundling), and even selling off their generation,
2. Some states and provinces were instituting “customer choice” options for selecting
energy providers, and
3. The developing power markets were requiring wide-area transmission reliability
assessment and dispatch solutions, which were beyond the capability of many Control
Areas to perform.
As a result, the NERC Operating Policies in place at that time, which centered on Control
Area operations, were beginning to lose their focus, and become more difficult to apply and
enforce.
The NERC Operating Committee formed the Control Area Criteria Task Force (CACTF) in
1999 to address this problem. The task force began by listing all the tasks required for
maintaining electric system reliability and then organizing these tasks into basic groups that
it called “functions.” The task force then attempted to assign these functions to the basic
“reliability organizations” such as Control Areas or Regional Transmission Organizations.
But that didn’t work because the Control Areas themselves were unbundling some of the
functions they traditionally performed, and the emerging Regional Transmission
Organizations and Independent System Operators, while following structures as defined in
Order 2000, were not alike
.
Realizing that there was no longer a common reliability organization structure, the Task
Force decided to build a “Functional Model” consisting of the functions that ensure
reliability. Then, organizations — whether they are traditional, vertically integrated control
areas, regional transmission organizations, independent system operators, independent
transmission companies or so on — can “roll up” those functions they perform, and register
with NERC as one or more of the Responsible Entities. Since the initial efforts of the CACTF,
the model has been expanded to incorporate planning related functions. This Functional
Model framework enables NERC to write its reliability standards in terms of the Responsible
Entities who perform the reliability functions.
Excerpted and revised from Version 2 of the NERC Functional Model, February 10, 2004
Introduction
The NERC Reliability Functional Model (“the Model”) provides the framework for the
development and enforcement of NERC’s Reliability Standards, as follows:
• The Model defines the set of Functions that must be performed to ensure the
reliability of the bulk electric system. Each Function consists of a set of reliability
Tasks. The Model assigns each Function to a Responsible Entity, that is, the entity
responsible for ensuring the Function is performed. The Model also defines the
interrelationships between that Responsible Entity and other Responsible Entities
(responsible for performing other Functions).
• NERC’s Standards Development Teams develop Reliability Standards and assign
each reliability requirement within a standard to a Responsible Entity, as defined in