Summer 2008 Issue
The introduction of multiple sources of electric power of different types and with a wide range of power output represents a new challenge that our industry needs to deal with. Electric power plants have been mainly large, utility owned facilities, so far. Their characteristics and behavior under different system conditions have been studied for many years. This resulted in the development and imp... More


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Industry News

Breaker Controlled Switching System

The Toshiba Controlled Switching System (TCSS) for circuit breakers has been developed to provide a sophisticated solution to eliminate unwanted electrical transients. Based on practical operational experience gained since 1989 Toshiba is now launching a new controlled switching system using the latest digital control and network computing technologies. The new switching controller features both h... More

Complete IEC 61850 Process Bus

Solution GE Digital Energy delivers a complete IEC 61850 Process Bussolution for intelligent protection and control with the Multilin HardFiberTM System. Replacing the need for thousands of copper wires in a substation, the Multilin HardFiber System replaces the copper wires with a few fiber optic cables.Reducing this need to install and maintain copper wires, used for signaling and monitoring in ... More

Industry Awards For Outstanding Technical Achievement

The IEEE Board of Directors has named 295 IEEE Senior Members to Fellow Grade effective 1 January 2008. The list includes three representatives of the global PAC community - Dr. Bogdan Z. Kasztenny, Canada; Vahid Madani and Kenneth Martin, USA. The grade of Fellow recognizes unusual distinction in the profession and is conferred by the Board of Directors upon a person with an extraordinary record ... More

Lifetime Achievement Award

The IEEE Power Engineering Society (PES) Lifetime Achievement Award was established in 2007 to recognize exceptional power engineers for outstanding career-long contributions to the art and science of electric power engineering. The inaugural recipient of this new award is one of the most active members of the protection and control community - Stanley Horowitz. The citation for the award states... More

Make Complex Alarming Simple

Easy and economical means of annunciation The new Schweitzer Engineering Laboratories' SEL-2523 Annunciator Panel provides an easy and economical means of annunciation in existing and new applications. It can be applied for various industrial, utility, and commercial uses. The flexibility of the communications and alarm configuration in this product allow it to be applied with little or no hard-... More

New Compact Protection Relays - Siemens

Siemens enhances its portfolio with the new SIPROTEC Compact 7SJ80 and 7SK80 protection relays that share a brand - new and powerful hardware with well proven algorithms from SIPROTEC 4. The 7SJ80 relays can be used for line/feeder protection of high and medium voltage networks with grounded, low-resistance grounded, isolated or a compensated neutral point. The multifunctional 7SJ80 provides a dir... More

NovaTech acquires Bitronics

NovaTech LLC, a provider of electric utility and process industry automation has acquired from AREVA T&D their measurement business assets, including the complete Bitronics Measurement Product line, its PowerServe®, MultiComm and other high-performance electricity measurement instruments. (see www. The measurement products will continue to be designed and manufa... More

OMICRON among the 50 best employers in Europe

OMICRON electronics has been rated again among the 50 best European employers (small and medium sized workplaces) and has been awarded for it by the Great Place to Work Institute. The success is based on the employees and their personal commitment. OMICRON offers an interesting working environment which is characterized by open communication and teamwork which encourage personal development... More

P847 Phasor Measurement Unit

AREVA' s new P847 Phasor Measurement Unit (PMU) is used to measure power system data in real time and report to a Phasor Data Concentrator for visualization, data storage and most importantly for running a variety of 'on line' and 'off line' applications in wide area control and protection. It is GPS synchronized and exceeds the requirements of IEEE C37.118 Level 1 with enhanced performance under ... More

Technology News

BigDog - The alpha male of a robot family

Our industry is moving forward in an effort to address the numerous challenges it faces. New technologies, specifically multifunctional Intelligent Electronic Devices and advanced high-speed broadband communications, help in improving the security of the electric power system under different system conditions. But it is also always a good idea to have a look outside, at other domains, and see if... More

Internet Addressing

The continuous increase of substation protection, automation and control systems based on a local area network, and especially the success of IEC 61850 has resulted in a huge number of devices with Ethernet interfaces to be used in such applications. This is makes many protection specialists set the IP address of the relays to allow each device to talk to its peers over the substation LAN. Probabl... More

Solar Tree energy sollutions

The move towards use of green energy resources is welcomed with many mixed feelings. On one hand people understand that we can not continue producing electric power using fossil fuels, while at the same time they suffer of the NIMBY (not in my backyard) syndrome. To a great extent this is because people don't like the way transmission towers or wind turbines look. A good example of how this perce... More

Cover Story

Impact of Distributed Generation

Operating DGs in parallel with utility distribution systems is not without hazards. This article discusses the current technology in the interconnection of DGs to utility distribution circuits. Generators of 10MW or less are typically connected to the utility grid at the distribution level. Protection requirements to connect DGs to the utility grid had typically been established by each utili... More

IEC 61850 Update

IEC 61850 is Growing

As an example, object models for the control of hydro power plants that have been developed by WG18, have been published as IEC 61850-7-410 and not as IEC 62344, which was the originally assigned number. Similar, WG17 of TC57 has prepared object models for distributed energy resources (DER) based on logical nodes. This will be published this year as IEC 61850-7-420. The numbering scheme ... More

Lessons Learned

Analysis of Simultaneous Faults Using Short Circuit Simulations and Fault Records

On August 14th, 2005, the National Grid System Control Center reported that at 16:01:30 a lightning stroke caused a fault on the 115kV O-141S line near the company's Millbury #302 substation. The substation and faulted line configuration are shown in Figure 2. The circuit breakers O141 and 29-41 at Millbury #302 and O141S at Nashua St tripped correctly by the line protection relays. As per the... More

Challenges and Opportunities

Substation and Control Centers matching modern substations and control centers

Before going back in time - briefly When SCADA systems started to be implemented in Control Centers, most of the substations were protected and controlled by electromechanical devices and some substations had static (electronic) devices. This meant that all substation secondary systems were based on one kind of analogue technology. Except for remote measurements, that required one transducer for ... More

Intelligent Grid

Intelligent Grid

Are you ready to travel the road to the intelligent grid? Since the moment Thomas Edison commissioned the world's first power system in 1882, the electric power industry has continually moved forward - to improve the functionality, efficiency, and availability of electricity. Through evolutionary advancements in technology, the industry has transformed the way we generate, deliver, and cons... More


Line Current Differential Relays Operating over SDH/SONET Networks

Conventional line differential relays utilize methods of synchronization to ensure that samples compared by relays at all terminals of a power transmission line are taken at the same time instant. The techniques employed are generally based on the premise that propagation delays in the communication link are equal for both send and receive paths. However, this premise is not necessarily valid... More

Legal Issue

Possible Legal Concerns

Author: Iana Apostolova J.D When a major power disaster strikes, countless individuals are affected and the most effective means of achieving legal satisfaction is to file a class action lawsuit. A prime example of this situation and its aftermath is the North American blackout of 2003. This issue's column provides a peak into the Northeast blackout, and a recap of its legal consequences, the ou... More

Sysrem Control

Distributed Energy Resources and the IEC 61850 Standards

Under its Technical Committee (TC) 57, IEC is developing normative standards (the 61850 series) to support open-systems-based communications for electric power systems. The formal name of this body of work is "Communication Networks and Systems for Power Utility Automation". These standards will enable easy assimilation of components into an interoperable communication system to support "smart dis... More

The Guru

The Guru

PAC World: Please tell us about the place where you were born and your family? MW: I was born in Pretoria, South Africa in 1933. I lived there until 1941. Pretoria was known for its blue skies and wonderful climate. It had a 12 month growing season with European fruit and crops in winter and tropical produce in summer. Although the war broke out in 1939 with South Africa joining the Al... More


Introduction to the History of Differential Protection

Forerunners of Differential Protection Already at the end of the 19th century some engineers talked about differential protection- it was the comparison of voltages and currents in single phases. A first proposal in 1896 compared the voltages of the two phases of a DC system with the neutral phase. A balance beam relay with coils on both sides was balanced as long as the voltages were eq... More

I Think

Do we have Guts?

Author: Marco C. Janssen, UTInnovation, Netherlands One of the best known examples of such a rule is the "N-1" criterion that defines that one element can fail without affecting the overall performance of the system. With the introduction of various new solutions and technologies such as CIM, IEC 61850, XML, etc our industry is currently going through a step change process. But somehow I get th... More

Industry Reports

Cigre Session 2008

Special reports are prepared by industry experts and are available in advance at the CIGRE web site in order to allow participants to prepare and submit their contributions for the Discussion Meeting. A zipped file containing all special reports can be downloaded at: session.asp The file is: B5_Special_Report_2008.pdf. For the CIGRE 2008 Session the protection an... More

IEEE Power Systems Relaying Committee

Recent wide-area electrical disturbances have clearly demonstrated the vulnerability of the interconnected power system when operated outside its intended design limits and have shown that protective relay systems are very often involved in major wide area perturbations. This important topic was recently addressed by the IEEE Power System Relaying Committee (PSRC). The working group C12 has create... More

Conference Reports

2008 PowerGrid Europe, Milan, Italy

The 2008 PowerGrid Europe conference and exhibition was held in conjunction with PowerGen and Renewable Energy Europe from June 3 to 5 in the Fiera Milano City in Milan, Italy. This Northern Italian "capital" is a welcoming city for visitors from around the world. The city is not only famous for the Duomo and the Opera House La Scala, it has as well a reputation for exclusive shopping. Th... More

Georgia Tech FDA Conference

The 11th Annual Georgia Tech Fault and Disturbance Analysis Conference was held 19 - 20 May, 2008 in Atlanta, Georgia, USA. This year there was a change in the conference venue - the historical Fox Theater. During the two days of the conference authors from several countries presented the twenty two papers selected by the technical committee. The papers covered a wide range of... More

Georgia Tech Protective Relaying Conference, USA

The 62nd Annual Georgia Tech Protective Relaying Conference was held in Atlanta, Georgia, USA from 21 to 23 May 2008. The Fox Theatre was the conference venue. The move from the Georgia Tech Conference Center was caused by the increased number of participants - more than 350, predominantly from the United States, but also from other countries around the world - as far as South Africa. Mos... More

IX Technical Seminar on Protection & Control, Belo Horizonte, Brazil

The IX Technical Seminar on Protection and Control was held 1 - 5 June 2008 at Belo Horizonte, Brazil. The host city is the third largest in Brazil and the capital of the state of Minas Gerais. It is surrounded by the Serra do Curral Mountains, which serve as a natural backdrop. The convention center is part of the life and history of the city of Belo Horizonte. Minascentro was created t... More

Protection Conference, Monterey, Mexico

The application of Synchrophasors was the topic that was a strong point of discussion among the participants. The IX Simposio  Iberoamericano  sobre Protección de Sistemas Eléctricos de Potencia, IX SIPSEP (IX Spanish-American Symposium of Protection of Electric Power Systems) was held in Monterrey, México from May 20-23, 2008 at the Camino Real Hotel. This is the main Protection Confer... More

VLPGO WG 1 Synchrophasor Applications Meeting

The VLPGO (Very Large Power Grid Operators) is an international association of the greatest Power System Operators, created with the task to debate common subjects, mainly of technical nature. This association brings together System Operators from all over the world, with a minimum of 50,000 MW of installed capacity. VLPGO activities are conducted through thematic working groups, established ... More

WAMS Conference, St. Petersburg, Russia

Saint Petersburg, one of the liveliest and most cosmopolitan cities in Russia, was the venue of the 2nd International Conference on Monitoring Power System Dynamics Performance. This beautiful city was founded in the beginning of the XVIII century as the capital of the Russian Empire. It is impressive and famous over the world for its architectural heritage, mixing baroque, neoclassical and Rus... More

Book Review

Protective Relaying for Power Generation Systems

First edition With the penetration of distributed generators of different sizes and operating principles at different voltage levels of the electric power system, it is clear that understanding well the requirements for their protection is becomes essential for every protection specialist. Protective Relaying for Power Generation Systems is a book that covers a wide range of topics and can h... More


Protection, Photography and Music

We often talk about the art and science of electric power systems protection. Since there are many cases when formulas and algorithms do not help, we need to use our intuition and sense of beauty. That is probably why there are people like Fernando among us. Work and Hobby The call to write this note motivated me to think about the relation between my profession and my hobbies. My profession is ... More

Final Thoughts

BeijingSifang June 2016