Lightning is a transient, high-current electric discharge with the height in kilometre range. Cloud-to-ground lightning is less common than the other kinds of lightning (i.e. cloud-to-cloud and interclub lightning), but they are more important for protection studies of electric and electronic apparatus used in power systems, information technology systems, etc. The complete discharge, known as flash, has a time duration of about 0.5 s and is made up of various components, including stepped leader, return-strokes and dart leaders. The part of a flash, which has been of great interest for protection purposes, is the return-stroke phase.

Chapter Contents:

• 9.1 Introduction
• 9.2 General formulation
• 9.2.1 Time-domain formulation
• 9.2.2 Frequency-domain formulation
• 9.3 Numerical treatment
• 9.3.1 Method of moments
• 9.3.2 Time-domain formulation
• 9.3.3 Frequency-domain formulation
• 9.3.4 Lossy half-space problem
• 9.4 Various AT models
• 9.4.1 Time-domain AT model
• 9.4.2 Time-domain AT model with inductive loading
• 9.4.3 Time-domain AT model with non-linear loading
• 9.4.4 Frequency-domain AT model
• 9.5 Numerical results
• 9.5.1 AT Model
• 9.5.1.1 Current profiles
• 9.5.1.2 Line charge density profiles
• 9.5.1.3 Electromagnetic fields
• 9.5.2 ATIL Model
• 9.5.2.1 Current profiles
• 9.5.2.2 Current dispersion
• 9.5.2.3 Current wave propagation speed
• 9.5.2.4 Electromagnetic fields
• 9.5.3 AT model with non-linear loading
• 9.5.3.1 Current profiles
• 9.5.3.2 Current peak and current rise time
• 9.5.3.3 Electromagnetic fields
• 9.5.3.4 Current wave propagation speed
• 9.5.4 Frequency-domain AT model
• 9.5.4.1 Current profiles
• 9.5.4.2 Electromagnetic fields
• 9.5.4.3 Electromagnetic fields above lossy half-space
• 9.6 Summary
• References

Inspec keywords: lightning; method of moments; clouds; atmospheric techniques

Other keywords: information technology systems; high-current electric discharge; electric apparatus; interclub lightning; integral approach; electronic apparatus; antenna models; power systems; lightning return-stroke phase; cloud-to-ground lightning; moment method; flash

Subjects: Atmospheric electricity; Instrumentation and techniques for geophysical, hydrospheric and lower atmosphere research; Cloud physics