Gurevich Digital Protective Relays

Problems and Solutions
Erscheinungsjahr 2010
ISBN: 978-1-4398-3786-3
Verlag: Taylor & Francis
Format: PDF
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 422 Seiten

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 on DPRs, giving users a valuable tool to help them anticipate possible problems, something sorely lacking in the literature.

Zielgruppe

Specialists in the power industry and relay protection.

Autoren/Hrsg.

Gurevich, Vladimir

Fachgebiete

• Technische Wissenschaften Elektronik | Nachrichtentechnik Elektronik Bauelemente, Schaltkreise
• Technische Wissenschaften Elektronik | Nachrichtentechnik Elektronik Mikrowellentechnik

Inhaltsverzeichnis

Basic Components of Digital Protective Relays
Semiconducting Materials and the p-n Junction
The Principle behind Transistors
Some Transistor Kinds
General Modes of the Bipolar Transistor
Transistor Devices in Switching Mode
Thyristors
Optocouplers
Electromagnetic Relays

Design and Functional Modules of Digital Protective Relays
Overall Structure and Design of Digital Protective Relays (DPRs)
Analog Input Modules
Output Relay Modules
Digital (Logic) Input Modules
Central Processing Units (CPU)
Internal Power Supplies

Problems with the Reliability of Digital Protective Relays
Reliability Myth
The Real State of Affairs with DPR Reliability
What to Do with All These Problems?
"Intellectualization" of Protective Relays: Good Intentions or the Road to Hell?

Logic Inputs in Digital Protective Relays
Reliability of Logic Inputs in DPRs
Increasing Noise Immunity of the Logical Inputs in DPRs

Problems with Output Electromechanical Relays
The Analysis of Actual Operating Conditions of the Output Relays in Digital Protective Relays
Analysis of the International Standards and Technical Specifications
Improvement of DPR Output Circuits

Problems with External Power Supplies
Electromagnetic Disturbances in the Power Network
Applying Uninterrupted Power Supply
Other Problems in the AC Network
Problems in DC Networks

Testing Digital Protective Relays
Problems with DPR Testing
New View on the Problem
Modern Test Systems for Digital Protective Relays
Modern RPTS Problems
Offered Solutions
Digital Rate of Change of Frequency Relays, and Problems in Testing It

Electromagnetic Intrusions on Digital Protective Relays
Electromagnetic Vulnerability of DPRs
Lightning Strikes
Switching Processes and Electromagnetic Fields Generated by Operating Equipment
Issues with Control Cables Shielding
Distortion of Signals in the Current Transformer Circuits
Optical-Electronic Currents and Voltage Transformers
The Harmonics Impact on the Measured Current and Voltage on DPRs
The Quality of Voltage in the Supply Mains
Intentional Destructive Electromagnetic Impacts

Alternative (Nondigital) Protective Relays
Universal Overcurrent Protective Relays
Reed Switches Are New Perspective Elements for Protective Relays
Polarized and Memory Reed Switches
Power Reed Switches
Overcurrent Protective Relays with Reed Switches
Simple, Very-High-Speed Overcurrent Protection Relays
Reed-Based Devices For Overcurrent Protection of HV DC Equipment
The New-Generation Universal-Purpose Hybrid Reed: Solid-State Protective Relays

Problems with International Standards
The Basic International Standard on Electromechanical Relays (IEC 61810-1)
The International Standard on Solid-State Relays (IEC 62314-1)
The International Standard on Reed Switches (IEC 62246-1)

New Concepts for DPR Design


Index

Über Autor(innen)

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