EN IEC 60034-27-1:2018

Rotating electrical machines - Part 27-1: Off-line partial discharge measurements on the winding insulation

Publication date:   Dec 17, 2018

Scope

This part of IEC 60034 provides a common basis for:
- measuring techniques and instruments;
- the arrangement of test circuits;
- normalization and testing procedures;
- noise reduction;
- the documentation of test results;
- the interpretation of test results, with respect to partial discharge off-line measurements on the winding insulation of rotating electrical machines.
The measurement methods described in this document are applicable to stator windings of machines with or without conductive slot coating and to the stator windings of machines made with form wound or random wound windings. In special cases like high voltage rotor field windings, this document is applicable as well. The measurement methods are applicable when testing with alternating sinusoidal voltages from 0,1 Hz up to 400 Hz.
Interpretation guidelines are given in this document and are applicable only if all the following requirements are fulfilled:
- Measurements performed with power frequency of 50 Hz or 60 Hz, or when testing with power supply within a frequency range of 45 Hz to 65 Hz.
- Form wound windings and winding components such as bars and coils.
- Winding with conductive slot coating. This is usually valid for machines with voltage rating of 6 kV and higher.
For machines with random wound windings, form-wound windings without conductive slot coating, and testing at frequencies differing from power frequencies, the interpretation guidelines are not applicable. The testing procedures for off-line PD-measurements of this document can be used for assessing the uniform quality of manufacturing or/and the trending of these kind of windings as well as converter driven machine windings.
NOTE Testing of low voltage machines with so called Type I insulation systems is defined in reference [10]1.
Testing procedures for qualification of converter driven high voltage machines with so called Type II insulation systems are dealt with in IEC 60034-18-42 (in addition to the optional electric tests described therein).