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The Synchrophasor Report

SEL Axion becomes first IEEE-certified PMU
Feb 19, 2016
Volume8, Issue2

In this issue of The Synchrophasor Report, Isaac West, a power engineer, highlights a recent certification that distinguishes the SEL-2240 Axion as the first and only IEEE-certified phasor measurement unit (PMU) in the world.

New synchroWAVe Central Release Focuses on Operations
Jan 1, 2016
Volume8, Issue1

In this issue of The Synchrophasor Report, Jared Bestebreur, an SEL power engineer, shares the new features of SEL-5078-2 synchroWAVe Central 1.8.

Simple In-Line Synchrophasor Network Emulation Using the SEL Real-Time Automation Controller (RTAC)
Oct 28, 2015
Volume7, Issue5

In this issue of The Synchrophasor Report, Jeff Otto, an automation engineer, briefly explains the necessary configuration of the SEL RTAC for highly controllable synchrophasor network emulation.

See Synchrophasor Data From Across North America for Free!
Sep 1, 2015
Volume7, Issue4

In this issue of The Synchrophasor Report, Jared Bestebreur, an SEL power engineer, announces the release of SEL’s online synchrophasors demo.

IEEE C37.118-2011 Synchrophasors Now in the SEL-735 Power Quality and Revenue Meter
Jul 1, 2015
Volume7, Issue3

In this issue of The Synchrophasor Report, Anaisha Jaykumar, SEL associate product engineer, describes PMU capabilities of the SEL-735 Power Quality and Revenue Meter.

Enhanced Synchrophasor Processing With the New SEL RTAC SVPplus Library
May 1, 2015
Volume7, Issue2

As a follow-up to the April issue, SEL-3555: Synchrophasor Processor, Jeff Otto, SEL automation engineer, details the advantages and interworking of the new SVPplus library for the SEL RTAC family.

SEL-3555: Synchrophasor Processor
Apr 1, 2015
Volume7, Issue1

In this issue, Darrin Kite, SEL automation engineer, discusses the capabilities and advantages of the new SEL-3555 Real-Time Automation Controller platform as a synchrophasor processor.

The Evolution of Synchrophasors
Apr 1, 2015
Volume7, Issue1

Charles Steinmetz first introduced the concept of using phasors to describe ac waveforms in 1893. In 1988 Virginia Tech researchers Dr. Phadke and Dr. Throp developed the first phasor measurement unit (PMU) that built upon Steinmetz’s concepts of measuring phasors by adding time stamps to the phasor data based on a common time reference, such as GPS. A time-stamped phasor value is simply called a synchrophasor, and it allows the comparison of measurements collected from geographically dispersed locations. It is synonymous with a PMU, which is a device that calculates the instantaneous voltage, current, and frequency.

Early in the 2000s, SEL was the first company to combine synchrophasor capability into protective relay products, thereby making PMUs much more affordable. Today nearly all SEL products support synchrophasor technology. This is paving the way for a new paradigm in how protection and control are implemented in the power system because the capability natively exists and simply needs to be "turned on." Now that synchrophasors are widely available from protective relays and meters, there are many applications that can leverage these data to improve the condition of our power system.

Modular PMU Solutions for Evolving Applications
Dec 1, 2014
Volume6, Issue5

As the demands of synchrophasor applications become more diverse, phasor measurement units (PMUs) must adapt to meet the changing needs. Challenges such as accurate time distribution, hard-to-reach measurement locations, and inadequate communications networks can seriously hinder the deployment of a synchrophasor system. While SEL has been integrating PMU capability into protective relays for over a decade, we wanted to create a new PMU with the flexibility to satisfy the measurement requirements of even the most demanding synchrophasor applications. This issue of The Synchrophasor Report highlights the SEL-2240 Axion as a versatile PMU solution.

Mitigating GPS Vulnerabilities
Nov 3, 2014
Volume6, Issue4

The Global Positioning System (GPS) is a global navigation satellite system that has found prolific use in applications such as navigation, construction, and precise time synchronization. As this technology has become a large part of power system applications for time synchronization in the past several years, threats and vulnerabilities have been identified, such as jamming, solar flares, and spoofing, that can affect the proper operation of power systems. This issue of The Synchrophasor Report explores concepts of designing resilient time-distribution systems for power system applications.

The SEL Real-Time Automation Controller: Bridging Technology Gaps With Extreme Versatility
Aug 1, 2014
Volume6, Issue3

SEL has been adding synchrophasor technology to protective relays at no additional cost since 2002. As of today, there are hundreds of thousands of SEL relays in the field with phasor measurement unit (PMU) capability. We love giving our customers the good news: “Your SEL relays are already PMU-capable—just turn on the functionality, and you’re in business!” This issue of The Synchrophasor Report highlights the SEL Real-Time Automation Controller (RTAC) as a protocol bridge between PMUs of the past and synchrophasor tools of the future.

Expand Archiving Capability With External Archives
Jun 2, 2014
Volume6, Issue2

A disturbance recording solution should provide sufficient versatility to allow easy integration with existing network infrastructure components, such as shared network storage and external hard drives. This issue of The Synchrophasor Report focuses on a new enhancement to SEL-5073 synchroWAVe Phasor Data Concentrator (PDC) Software that is sure to expand how and where your synchrophasor data are archived.

Correlate and Analyze Power System Data
Feb 3, 2014
Volume6, Issue1

This issue of The Synchrophasor Report highlights synchroWAVe Central’s new ability to correlate and analyze power system data. When combined with acSELerator Team SEL-5045 Software, relay event data are automatically populated and available for viewing in synchroWAVe Central. This allows users to easily access and perform detailed analysis for any event.

Life After Commissioning: Understanding and Tuning Your Synchrophasor System
Dec 2, 2013
Volume5, Issue7

One key focus of the synchrophasor community in 2013 is data quality. Regional coordination entities across the world are collecting synchrophasor data from utilities and recording metrics on data quality. This issue of the Synchrophasor Report focuses on tuning your phasor data concentrator (PDC) configuration to maximize high-quality data.

Increase Synchrophasor Data Reliability Using Port Mapping
Sep 2, 2013
Volume5, Issue6

In this issue of The Synchrophasor Report we will look at a way to provide redundant synchrophasor data between a utility and another organization, like an Independent System Operator (ISO) or a Regional Transmission Organization (RTO). Several ISOs and RTOs now have large synchrophasor systems that are bringing in data from utilities or transmission owners that may be more than 1,000 miles away. The value and importance of these data have increased and are now being integrated into operational and planning activities, thus the need for ensuring that the synchrophasor data reliably reaches the destination.

Using IP Multicasting in Your Synchrophasor System
May 1, 2013
Volume5, Issue4

This issue of The Synchrophasor Report discusses applying Internet Protocol (IP) multicast addressing as a way to communicate synchrophasor data across a wide-area communications network. Use of IP multicasting can be an efficient and convenient way to send phasor measurement unit (PMU) data and can minimize system settings changes as your synchrophasor system grows or changes over time.

Preserve Time-Stamped Information When Editing Synchrophasor .CSV Data in Microsoft Excel
Apr 1, 2013
Volume5, Issue3

Comma-separated value (CSV) is a common data format used to export IEEE C37.118 synchrophasor data. Periodically, it becomes necessary to edit the .CSV file directly. Spreadsheet applications are very useful for this purpose because data can be easily manipulated and calculations directly applied to a full set of data. One spreadsheet application in wide use is Microsoft Excel. If you have ever tried editing CSV synchrophasor data in Excel, you’ve probably found that the time-stamp column is improperly formatted so that synchrophasor applications are unable to import the edited data. This issue of The Synchrophasor Report will show you how to correctly format your data to retain the full precision of your synchrophasor time stamps.

Network Woes? Try WireShark.
Mar 1, 2013
Volume5, Issue2

Communications systems and network settings can be the largest sources of confusion when commissioning a synchrophasor system. In this issue of The Synchrophasor Report, we will highlight a software program called WireShark, which could prove to be the most versatile tool in your synchrophasor commissioning arsenal. WireShark is an open-source, multiplatform, packet analyzer. It non-invasively captures Ethernet traffic, decodes packets, and yes, it even understands IEEE C37.118-2005!

Got Latency?
Nov 1, 2012
Volume4, Issue5

One common concern with real-time synchrophasor systems is “how real-time is the data?” Or stated another way: “What is the latency between the point of measurement (at the phasor measurement unit) and the point of application?” In this issue of The Synchrophasor Report, we will look at the sources of latency and some new tools that can be used to measure latency. Knowing the latency at various points in the system is useful for a wide variety of system applications, such as configuring and commissioning the system. Also, understanding the communications system latency over time can provide a deeper understanding of how the system operates during periods of heavy and light communications traffic.

Commissioning a Synchrophasor System.
Jan 2, 2012
Volume4, Issue1

The relatively recent influx of DOE-sponsored synchrophasor projects has spurred the demand not only for synchrophasor technology, but more importantly, the know-how for commissioning such systems. This issue of The Synchrophasor Report covers some useful considerations for system commissioning as well as the services Schweitzer Engineering Laboratories Engineering Services (SEL ES) can provide for implementation assistance to customers in need.

Making Up for Lost Time: What Happens If I Temporarily Lose GPS Time?
Jun 1, 2011
Volume3, Issue3

In the April issue of The Synchrophasor Report, we discussed how synchrophasor measurements require a precise absolute time reference—one that provides better than 1 microsecond absolute accuracy. This time reference allows us to precisely measure voltage and current phasors across a wide area to better than 1 percent total vector error (TVE) as specified in the IEEE C37.118 Standard for Synchrophasors for Power Systems. Global Positioning System (GPS) satellite-synchronized clocks are the predominant means for providing precise time for phasor measurement unit (PMU) measurements. In this issue, we will examine ways to minimize the loss of the GPS time source.

It’s About Time: Synchrophasor Measurements Require a Precise, Absolute Time Reference
Apr 1, 2011
Volume3, Issue2

This issue of The Synchrophasor Report (TSR) covers accurate timing—one of the key technologies that make synchronized phasor measurements possible. As you know, synchrophasor measurements require a precise, absolute time reference. The IEEE C37.118-2005 synchrophasor standard specifies that a clock be accurate to better than 1 microsecond. This is to ensure that the total vector error (TVE) measured by a phasor measurement unit (PMU) is less than 1 percent. There are several clocks that provide this level of accuracy, including rubidium and cesium atomic clocks; however, they are expensive and sensitive to temperature and vibration. An alternative is to implement highly accurate reference clocks, such as the SEL-2401, SEL-2404, or SEL-2407, which are satellite-assisted clocks that use the Global Positioning System (GPS) as their absolute reference.

Protecting Synchrophasor Systems: Practical Steps to Secure Your System
Sep 1, 2010
Volume2, Issue5

Synchrophasor systems provide a new view of power system operation by providing real-time, accurate, time-aligned measurements from across the system. The most common use of these systems is for visualization and archiving of system data, with some customers using these systems for control and protection. Most synchrophasor systems installed today are not considered critical assets; however, SEL believes that security for synchrophasor systems should be treated similarly to other systems used in your power network. Furthermore, security must be considered as these systems communicate across large geographic areas, potentially involving untrusted communications channels and/or interconnecting with protection systems. This issue of The Synchrophasor Report discusses practical approaches to ensuring the security of your synchrophasor system.

Effectively Integrate More Photovoltaic (PV) Generation Sources Into the Grid
Jun 1, 2010
Volume2, Issue3

The SEL Distributed Coherent Systems group recently participated in a witness evaluation test as part of the U.S. Department of Energy (DOE) Solar Energy Grid Integration System (SEGIS) program. PV Powered, Inc., Northern Plains Power Technologies, Senus, Portland General Electric, and SEL partnered to demonstrate a smart islanding technique that uses synchrophasors in the Oregon Solar Highway project PV generation site. The project has 100 kW peak generation capability and supplies renewable power for lighting at the Interstate 5-Interstate 205 interchange at Tualatin near Portland. This issue provides an overview of the system configuration and the witness evaluation test.

Synchrophasors and Communications Bandwidth
Apr 1, 2010
Volume2, Issue2

Many customers are in the process of obtaining synchrophasor measurements from their power systems by installing phasor measurement units (PMUs). One concern with installing this new technology is how to get real-time synchrophasor information to a central location. This is of special concern for substations that are located at remote sites and typically have limited communications bandwidth. This article will review the communications standard defined for sending synchrophasor information and discuss different approaches for getting the right communications architecture for your needs.

Use Time-Synchronized Phasors for Real-Time Control
Aug 3, 2009
Volume1, Issue4

Utilities worldwide are rapidly deploying synchrophasors. Synchrophasors are no longer merely a research technology; rather, they are becoming preferred real-time power system solutions. This issue discusses ways to use the SEL-3378 Synchrophasor Vector Processor to detect an islanding condition and to create an adaptive load-shedding scheme.

Use the SEL-487E for Transformer Protection and Station PMU
Jan 1, 2009
Volume1, Issue1

Welcome to the premier issue of The Synchrophasor Report. We intend to provide a short, periodic update of what’s happening in the world of time-synchronized measurements along with practical applications of this new technology.