in this paper, design and application of a new digital protective relay based on fuzzy logicand value estimation to a radial power system protection was presented. a novel approach based onvalue estimation was investigated for the proposed fuzzy logic based protective relay. in addition to thetheoretical aspect of fuzzy logic, mathematical definition of value estimation, detection andmeasuremen...

Software models for protective relays offer an economic and feasible alternative to studying the performance of protective relays. Relay models have been long used in a variety of tasks, such as designing new relaying algorithms, optimizing relay settings and training personnel [1]. In order to be practical, software relay models must reproduce the actual operation of the physical relays. This ...

This document discusses applications of digital simulators in protective relay testing with an emphasis on end-user evaluation and testing of relays in laboratory facilities. A background on digital simulators and transient testing together with a description of a twoterminal simulator test setup are given first. Description of a transmission network model and its use for generation of transien...

Validation and diagnosis of relay operation is very important to protection engineers in fault analysis. This paper presents development of an expert system based automated analysis solution, which performs validation and diagnosis of digital protective relay operation in great detail by analyzing data contained in various relay reports and files. In the system, forward chaining reasoning is us...

Digital technology has advanced very significantly over the years both in terms of software tools and hardware available. It is now applied extensively in many area of electrical engineering including protective relaying in power systems. Digital relays have many advantages over the traditional analog relays. The digital relay is able to do what is difficult or impossible in the analog relays. ...

Advanced techniques for analysing operation of protective relays and related interactions with the power system are discussed. Three major issues are addressed: evaluation of existing physical relays, study of new and/or existing relays using relay models, and assessment of relay operation and its interaction with the power system using models of both relays and power system. The underlying app...

Power system protective relaying systems are striving to meet the demands of systems which are ever increasing in complexity. . High-speed digital relays must make decisions while the power system is still in transition. Understanding the operation and performance of microprocessor based relays requires new engineering tools. Current transformer (CT) and relay modeling are practical tools to ev...

This paper presents a novel methodology for testing modern protective relays. Its primary focus is a distance relay. The proposed methodology consists of both design and application testing. Design testing is aimed at assessing predictive relay behavior by measuring its real operating characteristic. Application testing has the form of transient testing and it is aimed at assessing the random a...

This paper presents five SIMULINK libraries for modeling, design, optimization and testing of digital protective relays. The new MATLAB based software package includes the following libraries: Relay Elements, Relays, Protection Systems, Input Signals and Tools. The paper presents the software package in detail. First, all the components are described including their functions and variety of ava...

Information systems and intelligent smart grid data analytics will have a critical role in managing the massive amount of data becoming available in power system substations. Digital protective relays are multi-functional intelligent electronic devices based on microprocessors, which are being installed in substations throughout the power grid. New digital relays are replacing old-fashioned ele...