Protection of electricity distribution networks / Juan M. Gers and Edward J. Holmes.

By: Gers, Juan M [author.].

Contributor(s): Holmes, E. J. (Edward J.), 1928 [author.] | Institution of Electrical Engineers.

Material type: materialTypeLabel

BookSeries: IEE power and energy series: 47.Publisher: London : Institution of Electrical Engineers, [2004]Description: xi, 342 pages : illustrations ; 24 cm.Content type: text Media type: unmediated Carrier type: volumeISBN: 9780863413575 (hardback); 0863413579.Subject(s): Electric power systems -- Protection

DDC classification: 621.319

Contents:

Introduction -- Calculation of short-circuit currents -- Classification and function of relays -- Current and voltage transformers -- Overcurrent protection -- Fuses, reclosers and sectionalisers -- Directional overcurrent relays -- Differential protection -- Distance protection -- Protection of industrial systems -- Industrial plant load shedding -- Protection schemes and substation design diagrams -- Installation, testing and maintenance of protection systems.

Holdings
Item type	Current library	Call number	Copy number	Status	Date due	Barcode	Item holds
General Lending	MTU Bishopstown Library Lending	621.319 (Browse shelf(Opens below))	1	Checked out	24/01/2022	00213312

Total holds: 0

Enhanced descriptions from Syndetics:

It is essential to provide suitable protection schemes for distribution networks in order to ensure that faults are quickly remedied. This reference guide uses detailed examples and exercises taken from actual case studies to explain the co-ordination and inception of protection schemes.

Bibliography: (pages 297-299) and index.

Table of contents provided by Syndetics

Preface and acknowledgements (p. xi)
Preface to 2nd edition (p. xiii)
1 Introduction (p. 1)
1.1 General (p. 1)
1.2 Basic principles of electrical systems (p. 3)
1.3 Protection requirements (p. 3)
1.4 Protection zones (p. 5)
1.5 Primary and back-up protection (p. 5)
1.5.1 Primary protection (p. 5)
1.5.2 Back-up protection (p. 5)
1.6 Directional protection (p. 7)
1.7 Exercise 1.1 (p. 9)
2 Calculation of short-circuit currents (p. 11)
2.1 Modelling for short-circuit current calculations (p. 11)
2.1.1 Effect of the system impedance (p. 11)
2.1.2 Effect of rotating machinery (p. 13)
2.1.3 Types of fault duty (p. 14)
2.1.4 Calculation of fault duty values (p. 16)
2.2 Methods for calculating short-circuit currents (p. 19)
2.2.1 Importance and construction of sequence networks (p. 22)
2.2.2 Calculation of asymmetrical faults using symmetrical components (p. 23)
2.2.3 Equivalent impedances for a power system (p. 26)
2.3 Supplying the current and voltage signals to protection systems (p. 26)
2.4 Calculation of faults by computer (p. 28)
3 Classification and function of relays (p. 31)
3.1 Classification (p. 31)
3.1.1 Construction (p. 31)
3.1.2 Incoming signal (p. 31)
3.1.3 Function (p. 32)
3.1.4 International identification of electrical devices (p. 32)
3.2 Electromechanical relays (p. 33)
3.2.1 Attraction relays (p. 33)
3.2.2 Relays with moveable coils (p. 34)
3.2.3 Induction relays (p. 35)
3.3 Evolution of protection relays (p. 38)
3.4 Numerical protection (p. 39)
3.4.1 General (p. 39)
3.4.2 Characteristics of numerical relays (p. 39)
3.4.3 Typical architectures of numerical relays (p. 40)
3.4.4 Standard functions of numerical relays (p. 41)
3.5 Supplies to the relay circuits (p. 43)
4 Current and voltage transformers (p. 45)
4.1 Voltage transformers (p. 45)
4.1.1 Equivalent circuit (p. 45)
4.1.2 Errors (p. 46)
4.1.3 Burden (p. 47)
4.1.4 Selection of VTs (p. 47)
4.1.5 Capacitor voltage transformers (p. 47)
4.2 Current transformers (p. 51)
4.2.1 Equivalent circuit (p. 51)
4.2.2 Errors (p. 52)
4.2.3 AC saturation (p. 52)
4.2.4 Burden (p. 53)
4.2.5 Selection of CTs (p. 53)
4.2.6 DC saturation (p. 59)
4.2.7 Precautions when working with CTs (p. 59)
5 Overcurrent protection (p. 63)
5.1 General (p. 63)
5.2 Types of overcurrent relay (p. 63)
5.2.1 Definite-current relays (p. 63)
5.2.2 Definite-time/current or definite-time relays (p. 66)
5.2.3 Inverse-time relays (p. 66)
5.3 Setting overcurrent relays (p. 66)
5.3.1 Setting instantaneous units (p. 67)
5.3.2 Coverage of instantaneous units protecting lines between substations (p. 68)
5.3.3 Setting the parameters of time delay overcurrent relays (p. 70)
5.4 Constraints of relay co-ordination (p. 73)
5.4.1 Minimum short-circuit levels (p. 73)
5.4.2 Thermal limits (p. 73)
5.4.3 Pick-up values (p. 75)
5.5 Co-ordination across Dy transformers (p. 86)
5.6 Co-ordination with fuses (p. 96)
5.7 Co-ordination of negative-sequence units (p. 96)
5.8 Overcurrent relays with voltage control (p. 97)
5.9 Setting overcurrent relays using software techniques (p. 98)
5.10 Use of digital logic in numerical relaying (p. 99)
5.10.1 General (p. 99)
5.10.2 Principles of digital logic (p. 99)
5.10.3 Logic schemes (p. 100)
5.11 Adaptive protection with group settings change (p. 102)
5.12 Exercises (p. 104)
6 Fuses, reclosers and sectionalisers (p. 109)
6.1 Equipment (p. 109)
6.1.1 Reclosers (p. 109)
6.1.2 Sectionalisers (p. 113)
6.1.3 Fuses (p. 114)
6.2 Criteria for co-ordination of time/current devices in distribution systems (p. 117)
6.2.1 Fuse-fuse co-ordination (p. 117)
6.2.2 Recloser-fuse co-ordination (p. 117)
6.2.3 Recloser-recloser co-ordination (p. 120)
6.2.4 Recloser-relay co-ordination (p. 122)
6.2.5 Recloser-sectionaliser co-ordination (p. 123)
6.2.6 Recloser-sectionaliser-fuse co-ordination (p. 123)
7 Directional overcurrent relays (p. 127)
7.1 Construction (p. 127)
7.2 Principle of operation (p. 128)
7.3 Relay connections (p. 128)
7.3.1 30[degree] connection (0[degree] AMT) (p. 129)
7.3.2 60[degree] connection (0[degree] AMT) (p. 129)
7.3.3 90[degree] connection (30[degree] AMT) (p. 130)
7.3.4 90[degree] connection (45[degree] AMT) (p. 131)
7.4 Directional earth-fault relays (p. 131)
7.5 Co-ordination of instantaneous units (p. 137)
7.6 Setting of time-delay directional overcurrent units (p. 141)
7.6.1 Pick-up setting (p. 141)
7.6.2 Time dial setting (p. 142)
7.7 Exercises (p. 146)
8 Differential protection (p. 149)
8.1 General (p. 149)
8.2 Classification of differential protection (p. 152)
8.3 Transformer differential protection (p. 152)
8.3.1 Basic considerations (p. 153)
8.3.2 Selection and connection of CTs (p. 154)
8.3.3 Percentage of winding protected by the differential relay during an earth fault (p. 159)
8.3.4 Determination of the slope (p. 161)
8.3.5 Distribution of fault current in power transformers (p. 162)
8.4 Differential protection for generators and rotating machines (p. 164)
8.5 Line differential protection (p. 164)
8.6 Busbar differential protection (p. 168)
8.6.1 Differential system with multiple restraint (p. 168)
8.6.2 High impedance differential system (p. 169)
8.7 Exercises (p. 170)
9 Distance protection (p. 173)
9.1 General (p. 173)
9.2 Types of distance relays (p. 174)
9.2.1 Impedance relay (p. 176)
9.2.2 Directional relay (p. 179)
9.2.3 Reactance relay (p. 180)
9.2.4 Mho relay (p. 181)
9.2.5 Completely polarised mho relay (p. 182)
9.2.6 Relays with lens characteristics (p. 183)
9.2.7 Relays with polygonal characteristics (p. 183)
9.2.8 Relays with combined characteristics (p. 185)
9.3 Setting the reach and operating time of distance relays (p. 185)
9.4 The effect of infeeds on distance relays (p. 188)
9.5 The effect of arc resistance on distance protection (p. 193)
9.6 Residual compensation (p. 194)
9.7 Impedances seen by distance relays (p. 195)
9.7.1 Phase units (p. 195)
9.7.2 Earth-fault units (p. 196)
9.8 Power system oscillations (p. 196)
9.9 The effective cover of distance relays (p. 199)
9.10 Maximum load check (p. 200)
9.11 Drawing relay settings (p. 203)
9.12 Intertripping schemes (p. 212)
9.12.1 Under reach with direct tripping (p. 213)
9.12.2 Permissive under reach intertripping (p. 213)
9.12.3 Permissive over reach intertripping (p. 214)
9.13 Distance relays on series-compensated lines (p. 214)
9.14 Technical considerations of distance protection in tee circuits (p. 215)
9.14.1 Tee connection with infeeds at two terminals (p. 215)
9.14.2 Tee connection with infeeds at all three terminals (p. 218)
9.15 Use of distance relays for the detection of the loss of excitation in generators (p. 219)
9.16 Exercises (p. 222)
10 Protection of industrial systems (p. 225)
10.1 Protection devices (p. 225)
10.1.1 Overcurrent relays (p. 225)
10.1.2 Direct acting devices in power and moulded-case circuit breakers (p. 225)
10.1.3 Combined thermal relay contactor and fuse (p. 226)
10.2 Criteria for setting overcurrent protection devices associated with motors (p. 226)
10.2.1 Thermal relays (p. 226)
10.2.2 Low voltage breakers (p. 227)
11 Industrial plant load shedding (p. 239)
11.1 Power system operation after loss of generation (p. 239)
11.2 Design of an automatic load shedding system (p. 240)
11.2.1 Simple machine model (p. 240)
11.2.2 Parameters for implementing a load shedding system (p. 241)
11.3 Criteria for setting frequency relays (p. 242)
11.3.1 Operating times (p. 242)
11.3.2 Determination of the frequency variation (p. 243)
11.4 Example of calculating and setting frequency relays in an industrial plant (p. 243)
11.4.1 Calculation of overload (p. 243)
11.4.2 Load to be shed (p. 243)
11.4.3 Frequency levels (p. 243)
11.4.4 Load shedding stages (p. 243)
11.4.5 Determination of the frequency relay settings (p. 244)
11.4.6 Verification of operation (p. 247)
12 Protection schemes and substation design diagrams (p. 251)
12.1 Protection schemes (p. 251)
12.1.1 Generator protection (p. 251)
12.1.2 Motor protection (p. 252)
12.1.3 Transformer protection (p. 258)
12.1.4 Line protection (p. 261)
12.2 Substation design diagrams (p. 261)
12.2.1 Single-line diagrams (p. 262)
12.2.2 Substation layout diagrams (p. 263)
12.2.3 Diagrams of AC connections (p. 264)
12.2.4 Diagrams of DC connections (p. 265)
12.2.5 Wiring diagrams (p. 266)
12.2.6 Logic diagrams (p. 268)
12.2.7 Cabling lists (p. 268)
13 Processing alarms (p. 269)
13.1 General (p. 269)
13.2 Alarm processing methods (p. 270)
13.3 Expert systems (p. 271)
13.4 Equivalent alarms (p. 272)
13.5 Rules (p. 273)
13.6 Finger printing approach (p. 273)
13.7 Hypothesis approach (p. 275)
14 Installation, testing and maintenance of protection systems (p. 283)
14.1 Installation of protection equipment (p. 283)
14.2 Testing protection schemes (p. 285)
14.2.1 Factory tests (p. 285)
14.2.2 Precommissioning tests (p. 285)
14.2.3 Periodic maintenance (p. 290)
14.3 Commissioning numerical protection (p. 292)
14.3.1 Setting the parameters (p. 292)
14.3.2 Performance tests (p. 293)
Bibliography (p. 297)
Appendix Solutions of exercises (p. 301)
Index (p. 339)