The international standard covering insulation co-ordination is IEC 60071, which provides the definitions, principles and rules for insulation co-ordination for threephase systems having a highest voltage above 1 kV. The collective IEC 60071 document also provides an application guide along with a computational guide to insulation co-ordination and the modelling of electrical networks.

Chapter Contents:

• 2.1 Introduction
• 2.2 Classification of dielectric stress
• 2.2.1 Power frequency voltage
• 2.2.2 Temporary overvoltages
• 2.2.3 Switching overvoltages
• 2.2.4 Lightning overvoltages
• 2.3 Voltage-time characteristics
• 2.4 Rated withstand voltage levels
• 2.5 Factors affecting switching overvoltages
• 2.5.1 Source configuration
• 2.5.2 Remanent charge
• 2.5.3 Transmission line length
• 2.5.4 Compensation
• 2.5.5 Circuit-breaker pole scatter
• 2.5.6 Point-on-wave of circuit-breaker closure
• 2.6 Methods of controlling switching surges
• 2.6.1 Circuit-breaker pre-insertion resistors
• 2.6.2 Metal oxide surge arresters
• 2.6.3 Circuit-breaker point-on-wave control
• 2.6.4 Comparison of switching overvoltage control methods
• 2.6.5 Application of insulation co-ordination for ultra high-voltage technology
• 2.7 Factors affecting lightning overvoltages entering substations
• 2.7.1 Backflashover
• 2.7.2 Direct strike
• 2.7.3 Attenuation of lightning overvoltage
• 2.8 Methods of controlling lightning overvoltages
• 2.8.1 Location of surge arresters
• 2.9 Conclusions
• References

Inspec keywords: insulation co-ordination; power system simulation; transmission networks; IEC standards; distribution networks

Other keywords: AC distribution systems; international standard; IEC 60071; threephase systems; electrical networks modelling; insulation co-ordination; AC transmission systems

Subjects: Insulation and insulating coatings; Power system planning and layout; Distribution networks; Power system protection