Current transformers (CTs) are used throughout the world as current transducers for protective relays in industrial, commercial, and utlity applications. Standard ratings and application guides deal with the steady-state sine wave behavior of current transformers. Despite the use of recommended rules applied to avoid transient saturation, it always occurs in certain critical relay applications.
Analyzing and Applying Current Transfomers is a reference book written for professionals concerned with the application andf operation of CTs used as current transducers for input to protective relays in electrical power systems. This book presents transformer concepts that provide the fundamentals to understand the non-linear characteristics, accuracy ratings, and transient behavior of current transformers.
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Chapter 1 : Introduction
Chapter 2 : Current Transformer Equivalent Circuit
Chapter 3 : Volt-Time Area and Saturated Waveforms
Chapter 4 : The Excitation Curve
Chapter 5 : Computer Simulation
Chapter 6 : Flux Density Limit of The Volt-Time Area
Chapter 7 : The Criterion to Avoid Saturation
Chapter 8 : A Case History
Chapter 9 : CT Application Rules
Chapter 10 : Transformer Differential Relay Applications
Chapter 11 : Generator Differential Relay Application
Chapter 12 : Bus Differential Relay Applications
Chapter 13 : Percentage Slope Characterstics
Chapter 14 : Alpha Plane Differential Characterstic
Chapter 15 : Determining The Slope for a Given Degree of Saturation
Chapter 16 : Bus and Machine Differential Applications
Chapter 17 : The Effect of Remanent Flux on The Slope Setting
Chapter 18 : The Impact of High Fault Current on Overcurrent Protection
Chapter 19 : Limitations of an 80 A Instantaneous Setting
Chapter 20 : Defining a CT Selection Criterion
Chapter 21 : Implementing Instantaneous Overcurrent Elements
Chapter 22 : The Cosine-Peak Adaptive Filter
Annex A : Volt-Time Area Computer Simulation
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