Table of Contents

1 Overview
  1.1 Scope
  1.2 Purpose
2 Normative references
3 Definitions
4 Criteria
  4.1 Safety codes and regulations
  4.2 Basic lightning impulse insulation level criteria
  4.3 Radio interference voltage and corona criteria
  4.4 Operating history
  4.5 Economic aspects
  4.6 Community acceptance
5 Substation insulation coordination
  5.1 Protective margins and arrester maximum continuous
      operating voltage
  5.2 Selection of basic lightning impulse insulation level
      and basic switch impulse insulation level
  5.3 Selection of electrical clearances
6 Electrical operating/design clearances
  6.1 General discussions
  6.2 Historical background
  6.3 Clearances based on lightning impulse conditions
  6.4 Clearances based on switching surge conditions
7 Electric maintenance/safety clearances
8 Substation voltage uprating and compact design
  8.1 BIL/System voltage ratio concept
  8.2 Other considerations
Annex A (informative) Bibliography
Annex B (informative) Example calculations

Abstract

Describes three-phase ac systems from 1 kV to 800 kV, provides recommended electrical operating and safety clearances and insulation levels in air-insulated electric supply substations; addresses insulation coordination procedures; provides design procedures for the selection and coordination of the insulation levels within the station as they relate to substation clearances; and addresses how reduced clearances in high-voltage ac substations will allow for compact bus arrangements and substation voltage uprating applications.

General Product Information

Published
Document Type	Standard
Status	Current
Publisher	Institute of Electrical & Electronics Engineers
Pages
ISBN
Supersedes	IEEE DRAFT 1427 : D14 2006