DIN EN 60034-18-42:2017-12

This document describes the qualification tests for electrical insulation systems that, based on experience, can withstand partial discharges in any part of the insulation system during the entire period of operation (Type II). In other words, for the insulation system of stator/rotor windings of single-phase or multi-phase alternating current machines that are exposed to frequent voltage impulses, caused for example by converters with pulse width modulation (PWM), and which are expected to withstand the partial discharges that occur during operation. Such insulation systems are generally used in rotating machines that have windings with preformed elements and are usually rated for more than 700 V RMS. Electrical qualification tests are specified that are carried out on representative test specimens to demonstrate their suitability for use in operation with voltage converters. The qualification procedure is completely different from that used for Type I insulation systems according to DIN EN 60034-18-41 (VDE 0530-18-41) and involves accelerated aging of the insulated test objects under time-lapse conditions. The manufacturer needs a lifetime curve for the insulation system (as described in DIN EN 60034-18-32 (VDE 0530-18-32), which can be used to estimate the service life under operating conditions when using a converter. Particular emphasis is placed on the evaluation of the overhang corona shielding system, which should be tested with both sinusoidal and impulse voltage. If it can be shown that the insulation system offers an acceptable life under appropriate aging conditions, then it is suitable for use. The responsible committee is DKE/K 311 "Drehende elektrische Maschinen" ("Rotating electrical machines") of the DKE (German Commission for Electrical, Electronic and Information Technologies) at DIN and VDE.