The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The paper is a continuation in a series that identifies more of the developing issues in relay testing - what was once well understood in a protection element's response is today a challenge in testing modern protection systems. Modern algorithms and the complexity of the combined protection element(s) scheme logic creates variable and sometimes unacceptable testing results when compared to manufacturer...
The paper identifies real world issues where the engineering calculations used to compute the variables that go into a power system network model can fall short of reality. This not only impacts the viability of the simulation tool used, but worse the accuracy of the data it provides to configure and set today's modern IED protection relays. The faulty result is often hidden until a fault of circumstance...
The paper identifies more of the developing issues in relay testing - what has previously been well understood protection elements/functions used in designing feeder protection systems has become intertwined with modern complex programmable logic. The core issue is the same modern algorithms and combined protection element scheme logic that enables modern feeder protection to operate securely and...
This paper is part two of the subject title and identifies some of the developing issues in testing what has here to fore been well understood protection elements we commonly used in designing modern protection systems. The core issue is the complexity of today's combined protection element scheme logic that enables these “understood” protection elements to function more securely and reliably - but...
This paper discusses the traditional approach to field testing a series compensated line protection system. The problem domain is analyzed to establish the various test cases required to prove the local/remote protection system and the difficulty in using traditional testing methods in creating effective tests, whether local only or End-to-End tests. Techniques are identified to break down the testing...
This paper discusses the increasing interest in performing End to End testing on modern protection systems. There are many and varied approaches to this test method, from simplistic to overly complex. What is really required and what really makes this test method valuable? What are the technical challenges and how to resolve them? These and other questions are answered. This paper makes a comparison...
This paper identifies some of the developing issues in testing what has here to fore been well understood protection elements we commonly used in designing modern protection systems. The core issue is the complexity of the combined protection element scheme logic that enables these “understood” protection elements to function more securely and reliably - but also prevent us from using legacy testing...
Functional and application testing is the most widely accepted testing practice for protection and control systems and is required to ensure that a System Integrity Protection Scheme (SIPS) and each of its components are going to operate as designed under different system conditions. The paper discusses in detail the requirements for functional testing of devices and distributed functions used in...
Synchrophasor Standards have evolved since the introduction of the first one, IEEE Standard 1344, in 1995. IEEE Standard C37.118-2005 introduced measurement accuracy under steady state conditions as well as interference rejection. In 2009, the IEEE started a joint project with IEC to harmonize real time communications in IEEE Standard C37.118-2005 with the IEC 61850 communication standard. These efforts...
The paper discusses some of the engineering practices that have been used to design modern protection systems — most of which preclude the ability to field test them for either commissioning or routine testing requirements. This results in long term costs that far exceed the short term gain of the initial cost of the installed system. This paper makes specific recommendations to improve this “up front”...
This paper reviews the principles of digital design in protection and control systems across many industries — not just Power Systems — and explores why we still test them. The test methods used by other industries and the processes that mandate them are presented. Comparisons are made to our own energy industry and parallels made to what we should be improving on as an industry to ensure system security...
The paper discusses the typical utility approach to End-to-End testing and the suitability of using those results and documentation to satisfy the current revised NERC/FERC reliability standard PRC-005–2. This testing method provides great operational and economic advantages and analyzing problem areas in a protection scheme. Proper end to end testing techniques can greatly reduce the chances of wide...
This paper reviews past and present NERC/FERC requirements for relay testing of grid connected protection systems in the US/Canada with a focus on the final draft of PRC-005–2. It will attempt to clarify core requirements that are changing past testing philosophies and address practical testing methods for legacy relays and newer multifunctional digital relays. During the past decade, protective relays...
The paper reviews traditional CT testing and its inability to provide critical data necessary for relay transient response analysis. It then introduces a method for making improved field testing resulting in significantly more information about the CT, its performance in the given application and at the actual burden. Use of this expanded test data makes further analysis possible for transient simulation...
The paper analyzes the requirements for maintenance related testing in order to reduce the cost and potential problems related to such testing. It discusses the concept of monitoring versus testing based on the available monitoring functions in state-of-the-art multifunctional distance protection IEDs and the impact of IEC 61850 on the maintenance testing process.
Phasor Measurement Units (PMUs) are getting increasingly popular. Major incidents in the near past, such as the big blackouts in 2003 in the northeast of the USA and in Italy, have raised the interest in all means that support the observation of the condition of the electrical power network, assessing system stability, and predicting problems. PMUs are perceived to be valuable tools for this. The...
The philosophy of testing relay protection systems has changed very little in most utilities. However the devices themselves have changed greatly. Testing for some devices has been called into question as no testing at all has been proposed. This paper reviews why we tested in the past and what methods were used. The paper further reviews future testing needs and strives to bring a resolution to the...
Modern distance protection relays are complex multifunctional devices based on classical or advanced operating principles that impose special requirements for their testing. The paper analyzes the functionality, the functional hierarchy and the schemes typically available in distance relays. It then discusses the methodology for testing of such relays. Testing of individual protection and non-protection...
The paper discusses in detail the requirements for functional testing of devices and distributed functions used in SIPS. The methods for testing of such systems are proposed based on the testing of individual IEDs used in the system, distributed functions within a substation and between substations, complete SIPS and End-to-end testing of SIPS. Methods for the testing of complex SIPS, such as white...
Advanced distance protection relays are complex multifunctional devices designed to provide optimal performance under different system conditions and with the ability to use IEC 61850 communications for process and station bus applications. This imposes special requirements for their testing. The paper analyzes the functionality, the functional hierarchy and the schemes typically available in distance...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.