IEEE Guide for the Application of Current Transformers Used for Protective Relaying Purposes

Title Page......Page 1
Participants......Page 3
CONTENTS......Page 5
2. References......Page 7
3. Definitions......Page 8
4. Current transformer characteristics and classification......Page 9
4.1 Current transformer equivalent circuit and phasor diagrams......Page 10
4.2 Current transformer secondary excitation characteristics......Page 11
4.3 Knee-point voltage......Page 12
4.4 Current transformer accuracy......Page 13
4.5 Dynamic characteristics......Page 17
4.6 The effects of remanence......Page 21
4.7 Fundamental transformer equation......Page 24
5.1 Current transformer burdens......Page 25
5.3 Long-term and short-term thermal ratings......Page 27
5.5 Connecting current transformers in series......Page 28
5.7 Auxiliary current transformers......Page 29
5.8 Bus configuration......Page 30
5.9 Current transformer location......Page 31
5.11 Determining current transformer steady-state performance using secondary excitation curves......Page 32
6.3 Saturation effects on differential relays......Page 33
7.1 Overcurrent relays......Page 34
7.2 Differential protection......Page 38
7.3 Distance protection......Page 55
7.4 Other types of high-speed protection......Page 56
Annex A—IEC standards on current transformers......Page 57
Annex B—List of IEEE standard C values and burdens......Page 59
Annex C—Remanent flux in current transformers......Page 60
Annex D—Bibliography......Page 61