Digital Protective Relays Problems and Solutions

Digital (microprocessor-based) protection relays (DPR) are dominating the global market today, essentially pushing all other types of relays out of the picture. These devices play a vital role in power operations for fields ranging from manufacturing, transportation, and communication to banking and healthcare.

Digital Protective Relays: Problems and Solutions offers a unique focus on the problems and disadvantages associated with their use, a crucial aspect that goes largely unexamined. While there is already a massive amount of literature documenting the benefits of using digital relays, devices as sophisticated as DPR obviously have faults and drawbacks that need to be understood. This book covers these, delving into the less familiar inner workings of DPR to fill a critical literary void and help decision makers and specialists in the field of protection relays find their way out of the informational vacuum. The book provides vital information to assist them in evaluating relay producers' claims and then choose the right product.

Tearing away the informational "curtain" that exists today, this book:

• Describes construction of functional modules of existing relays



• Analyzes drawbacks and problems of digital relays



• Details specific technical problems and their solutions



• Assesses dangers of intentional destructive electromagnetic intrusions



• Discusses alternative (non-microprocessor-based) protection relays, and problems related to international standards

Focusing on practical solutions, this book explains how to correctly choose digital relays and ensure their proper use while avoiding the many problems they can present. The author avoids mathematics and theory in favor of more practical, tangible information not easily found elsewhere. Setting itself apart from other books on the subject, this volume shines a light into the long hidden "black box" of information

Basic Components of Digital Protective Relays. Design and Functional Modules of Digital Protective Relays. Problems with the Reliability of Digital Protective Relays. Logic Inputs in Digital Protective Relays. Problems with Output Electromechanical Relays. Problems with External Power Supplies. Testing Digital Protective Relays. Electromagnetic Intrusions on Digital Protective Relays. Alternative (Nondigital) Protective Relays. Problems with International Standards. New Concepts for DPR Design. Index.

Vladimir Gurevich is with the Israel Electric Corporation in Haifa, Israel.