BS IEC 1000-3.6 : 1996

FOREWORD
INTRODUCTION
Clause
1 Scope
2 Normative references
3 Basic concepts
4 General principles
5 General guidelines for the assessment of emission
    levels
    5.1 Assessment of harmonic injection from
          distorting loads
    5.2 Harmonic impedance
          5.2.1 Simplified assessment methods
          5.2.2 Detailed manual calculations
6 Summation laws
    6.1 First summation law
    6.2 Second summation law
7 Emission limits for distorting loads in MV systems
    7.1 Stage 1: simplified evaluation of disturbance
          emission
          7.1.1 Weighted distorting power as a
                  reference value
          7.1.2 Relative harmonic currents as emission
                  limits
    7.2 Stage 2: emission limits relative to actual
          network characteristics
          7.2.1 Simplified approach based on the first
                  summation law

          7.2.2 General approach based on the second
                  summation law
    7.3 Stage 3: acceptance of higher emission levels
          on an exceptional and precarious basis
8 Emission limits for distorting loads in HV systems
    8.1 Stage 1: simplified evaluation of disturbance
          emission
    8.2 Stage 2: emission limits relative to actual
          network characteristics
          8.2.1 Assessment of the total available power
          8.2.2 Individual emission limits
    8.3 Stage 3: acceptance of higher emission levels
          on an exceptional and precarious basis
9 Emission limits for interharmonics
10 Emission limits for telephone interference effects
Annexes
A Example of the "worst case impedance curve" approach
B Example of the manual calculation of the harmonic
    impedance of a MV network at the PCC
C Example of particular rules for stage 1 limits in
    MV networks
D General case of MV loads spread along the feeders:
    sharing of emission
E Example of application of the approaches proposed for
    assessing emission limits
F Examples in some typical HV cases
G List of principal symbol letters, subscripts and
    symbols
H Bibliography

Defines principles for use as a basis for determination of the requirements for connection of large distorting loads (producing harmonics and/or interharmonics) to public power systems. The main concern is the provision of guidelines for engineering practices for ensuring adequate service quality for all connected customers.