AS 4372-1996

1 - AS 4372-1996 HIGH-VOLTAGE ALTERNATING CURRENT CIRCUIT-BREAKERS-INDUCTIVE LOAD SWITCHING
4 - PREFACE
5 - CONTENTS
7 - Section 1: General
7 - 1.1 Scope
7 - 1.2 Normative references
7 - 1.3 Auxiliary voltages and pressures
7 - Section 2: Transformer magnetizing currents
7 - 2.1 General
7 - 2.2 Transformer magnetizing current for circuit-breakers with rated voltages of 100 kV and above
8 - 2.3 Transformer magnetizing current for circuit-breakers with rated voltages below 100 kV
8 - Section 3: High-voltage motor switching tests
8 - 3.1 Applicability
8 - 3.2 General
10 - 3.3 Characteristics of the supply circuits
10 - 3.3.1 Supply circuit A
10 - 3.3.2 Supply circuit B
10 - 3.4 Characteristics of the load circuit
11 - 3.4.1 Motor substitute circuit 1
11 - 3.4.2 Motor substitute circuit 2
11 - 3.5 Test voltage
12 - 3.6 Test duties
12 - 3.7 Test measurements
13 - 3.8 Behaviour and condition of circuit-breaker
13 - 3.9 Test report
15 - Section 4: Shunt reactor current switching tests
15 - 4.1 Applicability
15 - 4.2 General
15 - 4.3 Test circuits
17 - 4.4 Characteristics of the supply circuit
17 - 4.5 Characteristics of the connecting leads
17 - 4.6 Characteristics of the load circuits
19 - 4.6.1 Load circuit 1
19 - 4.6.2 Load circuit 2
19 - 4.7 Earthing of the test circuit
19 - 4.8 Test voltage
20 - 4.9 Test duties
21 - 4.10 Test measurements
21 - 4.11 Test results
21 - 4.12 Test report
23 - Section 5: Application guide for a.c. high-voltage circuit-breakers for shunt reactor current switching
23 - 5.1 Appilcability
23 - 5.2 Purpose
23 - 5.3 General application conditions
23 - 5.3.1 Maximum voltage for application
23 - 5.3.2 Frequency
24 - 5.3.3 Shunt reactor load current
24 - 5.3.4 Fault interrupting capability
24 - 5.3.5 Break time
24 - 5.3.6 Transient overvoltages
25 - 5.3.7 Frequency of operation
25 - 5.4 Switching conditions
25 - 5.4.1 General
25 - 5.4.2 Shunt reactor and station characteristics
25 - 5.4.3 Circuit-breaker characteristics
26 - 5.5 Directly earthed reactors (basic overvoltage generation phenomena)
29 - 5.5.1 Current chopping
30 - 5.5.2 Chopping overvoltages
31 - 5.5.3 Recovery voltage across circuit-breaker
32 - 5.5.4 Re-ignitions
33 - 5.5.5 Re-ignition overvoltages
36 - 5.5.6 Oscillation modes
36 - 5.5.7 High-frequency current interruption
36 - 5.5.8 Multiple re-ignitions and voltage escalation
37 - 5.5.9 Energizing transients
37 - 5.6 Unearthed reactors
38 - 5.6.1 Current chopping
38 - 5.6.2 Recovery voltage across circuit-breaker
38 - 5.6.3 Chopping and re-ignition overvoltages
39 - 5.6.4 Application
41 - 5.7 Neutral reactor earthed reactors
42 - 5.7.1 Current chopping
42 - 5.7.2 Recovery voltage across circuit-breaker
42 - 5.7.3 Chopping and re-ignition overvoltages
42 - 5.7.4 Application
44 - 5.8 Limitation of overvoltages
44 - 5.8.1 General
44 - 5.8.2 Shunt reactor surge arrester protection
47 - 5.8.3 Circuit-breaker auxiliary equipment
48 - 5.9 Circuit-breaker testing
49 - 5.9.1 Auxiliary voltages and pressures
49 - 5.9.2 Load circuits
49 - 5.9.3 Test duties
49 - 5.9.4 Criteria for successful testing
49 - 5.9.5 Evaluation of circuit-breaker characteristics
50 - 5.10 Circuit-breaker specification
50 - 5.10.1 Dielectric withstand capability
50 - 5.10.2 Interrupting current rating
50 - 5.10.3 Shunt reactor rating
50 - 5.10.4 Shunt reactor current
51 - 5.10.5 Load side characteristics
51 - 5.10.6 Overvoltage limits
51 - 5.10.7 Earthing arrangement
51 - 5.10.8 Break time
52 - 5.10.9 Mechanical endurance
52 - 5.10.10 Tender information
53 - Annex A - Shunt reactor characteristics
53 - A.1 Shunt reactors rated 72,5 kV and above
54 - A.2 Shunt reactors rated below 72,5 kV
55 - Annex B - System and station characteristics
55 - B.1 System characteristics
55 - B.2 Station characteristics
57 - Annex C - General derivation of chopping and re-ignition overvoltages
57 - C.1 General
57 - C.2 Chopping overvoltages
60 - C.3 Re-Ignition overvoltages
63 - Annex D - Oscillation modes
63 - D.1 General
63 - D.2 Load side oscillations
63 - D.3 Re-ignition oscillations
65 - D.4 Interaction between phases
68 - Annex E - Application of laboratory test results to actual shunt reactor installations
68 - E.1 General
68 - E.2 Overvoltage estimation procedures
72 - E.3 Case studies
79 - Annex F - Statistical formulae for derivation of, chopping and re-ignition overvoltages
79 - F.1 General
79 - F.2 Chopping number independent of arcing time
79 - F.3 Chopping number dependent on arcing time
80 - Annex G - Bibliography

Applies to circuit-breakers which are used for switching of transformer magnetizing currents or currents of high-voltage motors and shunt reactors. It also applies to contactors used for switching the currents of high-voltage motors. This Standard is identical with and has been reproduced from IEC 1233:1994.

This report is applicable to circuit-breakers which are used for switching of:- transformer magnetizing currents, or- currents of high-voltage motors, or - currents of shunt reactors.It is also applicable to contactors used for switching the currents of high-voltage motors.

First published as AS 4372-1996.