Short circuits in power systems : a practical guide to IEC 60 909

The first book to present a practical route to the correct design of electrical networks based on the rules set by IEC 60 909 international standard. The author incorporates his many years of experience in the design and planning of such electrical systems at Siemens, among others. The accompanying software allows users to perform all the necessary calculations with ease, greatly facilitating the planning of electrical systems conforming to the IEC standard.

Foreword	p. V
Symbols and Indices	p. XIII
1 Terms and Definitions	p. 1
1.1 Time behavior of the short circuit current	p. 3
1.2 Short circuit path in the positive-sequence system	p. 4
1.3 Classification of short circuit types	p. 5
1.4 Methods of short circuit calculation	p. 7
1.4.1 Equivalent voltage source	p. 7
1.4.2 Superposition method	p. 9
1.4.3 Transient calculation	p. 10
1.5 Calculating with reference variables	p. 10
2 General Information About IEC 60 909	p. 11
3 The Significance of IEC 60 909	p. 13
4 Supply Networks	p. 17
4.1 Calculation variables for supply networks	p. 17
4.2 Lines supplied from a single source	p. 17
4.3 Radial networks	p. 18
4.4 Ring networks	p. 18
4.5 Meshed networks	p. 19
5 Network Types for the Calculation of Short Circuit Currents	p. 21
5.1 Low voltage network types	p. 21
5.2 Medium voltage network types	p. 23
6 Systems up to 1 kV	p. 29
6.1 TN systems	p. 29
6.2 Calculation of fault currents	p. 31
6.3 TT systems	p. 34
6.4 IT systems	p. 35
6.5 Transformation of the network types described to equivalent circuit diagrams	p. 36
7 Neutral Point Treatment in Three-phase Networks	p. 39
7.1 Networks with isolated free neutral point	p. 42
7.2 Networks with grounding compensation	p. 43
7.3 Networks with low impedance neutral point treatment	p. 44
8 Impedances of Three-phase Operational Equipment	p. 47
8.1 Network feed-ins	p. 47
8.2 Synchronous machines	p. 49
8.3 Transformers	p. 51
8.3.1 Short circuit current on the secondary side	p. 52
8.3.2 Voltage regulating transformers	p. 57
8.4 Cables and overhead lines	p. 58
8.5 Short circuit current limiting	p. 70
8.6 Asynchronous machines	p. 71
8.7 Consideration of capacitors and non-rotating loads	p. 72
8.8 Consideration of static converters	p. 73
9 Impedance Corrections	p. 75
9.1 Correction factor K[subscript G] for generators	p. 76
9.2 Correction factor K[subscript KW] for power plant block	p. 77
9.3 Correction factor K[subscript T] for transformers with two and three windings	p. 79
10 The Method of Symmetrical Components	p. 81
10.1 Symmetrical components	p. 82
10.2 Impedances of symmetrical components	p. 85
11 Calculation of Short Circuit Currents	p. 91
11.1 Three-pole short circuits	p. 91
11.2 Two-pole short circuits with contact to ground	p. 93
11.3 Two-pole short circuit without contact to ground	p. 93
11.4 Single-pole short circuits to ground	p. 94
11.5 Peak short circuit current i[subscript p]	p. 97
11.6 Symmetrical breaking current I[subscript a]	p. 99
11.7 Steady state short circuit current I[subscript k]	p. 102
12 Motors in three-phase Networks	p. 105
12.1 Short circuits at the terminals of asynchronous motors	p. 105
12.2 Motor groups supplied from transformers with two windings	p. 107
12.3 Motor groups supplied from transformers with different nominal voltages	p. 107
13 Mechanical and Thermal Short Circuit Strength	p. 111
13.1 Mechanical short circuit current strength	p. 111
13.2 Thermal short circuit current strength	p. 112
13.3 Limitation of short circuit currents	p. 120
14 Calculations for Short Circuit Strength	p. 127
14.1 Short circuit strength for medium voltage switchgear	p. 127
14.2 Short circuit strength for low voltage switchgear	p. 128
15 Equipment for Overcurrent Protection	p. 131
16 Short Circuit Currents in DC Systems	p. 143
16.1 Resistances of line sections	p. 145
16.2 Current converters	p. 146
16.3 Batteries	p. 147
16.4 Capacitors	p. 148
16.5 DC motors	p. 149
17 Programs for the Calculation of Short Circuit Currents	p. 151
18 Examples: Calculation of Short Circuit Currents	p. 153
18.1 Example 1: Radial network	p. 153
18.2 Example 2: Proof of protective measures	p. 155
18.3 Example 3: Connection box to service panel	p. 158
18.4 Example 4: Transformers in parallel	p. 159
18.5 Example 5: Connection of a motor	p. 160
18.6 Example 6: Calculation for a load circuit	p. 162
18.7 Example 7: Calculation for an industrial system	p. 164
18.8 Example 8: Calculation of three-pole short circuit current and peak short circuit current	p. 166
18.9 Example 9: Meshed network	p. 168
18.10 Example 10: Supply to a factory	p. 171
18.11 Example 11: Calculation with impedance corrections	p. 172
18.12 Example 12: Connection of a transformer through an external network and a generator	p. 176
18.13 Example 13: Motors in parallel and their contributions to the short circuit current	p. 177
18.14 Example 14: Proof of the stability of low voltage systems	p. 180
18.15 Example 15: Proof of the stability of medium and high voltage systems	p. 182
18.16 Example 16: Calculation for short circuit currents with impedance corrections	p. 193
18.17 Example 17: Calculation with per-unit magnitudes	p. 195
Appendices Calculation Tools for Electrical Engineering	p. 197
1 The Elaplan program	p. 199
2 The KUBS plus Program	p. 251
Index	p. 261

Available:*

On Order

Summary

Summary

Table of Contents