WG 3 - TC 112/WG 3

IEC TS 61934:2024 is applicable to the off-line electrical measurement of partial discharges (PDs) that occur in electrical insulation systems (EISs) when stressed by repetitive voltage impulses generated from power electronics devices.
Typical applications are EISs belonging to apparatus driven by power electronics, such as motors, inductive reactors, wind turbine generators and the power electronics modules themselves.
NOTE Use of this document with specific products can require the application of additional procedures.
Excluded from the scope of this document are:
- methods based on optical or ultrasonic PD detection,
- fields of application for PD measurements when stressed by non-repetitive impulse voltages such as lightning impulse or switching impulses from switchgear.
This edition includes the following significant technical changes with respect to the previous edition:
a) background information on the progress being made in the field of power electronics including the introduction of wide band gap semiconductor devices has been added to the Introduction;
b) voltage impulse generators; the parameter values of the voltage impulse waveform have been modified to reflect application of wide band gap semiconductor devices.
c) PD detection methods; charge-based measurements are not described in this third edition nor are source-controlled gating techniques to suppress external noise.
d) Since the previous edition in 2011, there have been significant technical advances in this field as evidenced by several hundreds of publications. Consequently, the Bibliography in the 2011 edition has been deleted in this third edition.

IEC 61251:2015 describes many of the factors involved in voltage endurance tests on electrical insulating materials and systems. It describes the voltage endurance graph, lists test methods illustrating their limitations and gives guidance for evaluating the sinusoidal a.c. voltage endurance of insulating materials and systems from the results of the tests. This International Standard is applicable over the voltage frequency range 20 Hz to 1 000 Hz. The general principles can also be applicable to other voltage shapes, including impulse voltages. The terminology to be used in voltage endurance is defined and explained. This first edition of IEC 61251 cancels and replaces the second edition of IEC TS 61251, published in 2008. This edition constitutes a technical revision and includes the following significant technical changes with respect to the second edition of IEC TS 61251:
a) upgrade from Technical Specification to an International Standard;
b) clarification of issues raised since publication of IEC TS 61251.

IEC 60243-3:2013 gives requirements additional to those in IEC 60243-1 for the determination of the electric strength of solid insulating materials under 1,2/50 µs impulse voltage stress. This third edition cancels and replaces the second edition, published in 2001, and constitutes an editorial revision.
This publication is to be read in conjunction with IEC 60243-1:2013.

L'IEC 60243-2:2013 donne les exigences complémentaires à celles de la CEI 60243-1 pour la détermination de la rigidité diélectrique des matériaux isolants solides sous tension continue. Cette troisième édition annule et remplace la deuxième édition parue en 2001 et constitue une révision éditoriale.
Cette publication doit être lue conjointement avec la CEI 60243-1:2013.

IEC 60243-1:2013 provides test methods for the determination of short-time electric strength of solid insulating materials at power frequencies between 48 Hz and 62 Hz. This standard does not cover the testing of liquids and gases, although these are specified and used as impregnates or surrounding media for the solid insulating materials being tested. NOTE: Methods for the determination of breakdown voltages along the surfaces of solid insulating materials are included.

IEC 62068:2013 applies to electrical equipment, regardless of voltage, containing an insulation system, which is:
- connected to an electronic power supply, and
- requires an evaluation of insulation endurance under repetitive voltage impulses. This standard proposes a general test procedure to facilitate screening of electrical insulating materials (EIM) and systems (EIS) and to achieve a relative evaluation of insulation endurance under conditions of repetitive impulses. This first edition of IEC 62068 replaces IEC 62068-1:2003. It has been re-numbered as IEC 62068, as decided at the Plenary Meeting of TC 112 in Prague 2011. The main changes with regard to IEC 62068-1:2003 concern the terms and definitions which are now aligned, in part, on IEC;TS 61934 and IEC;TS 60034-18-42.

IEC/TS 61934:2011(E) is applicable to the off-line electrical measurement of partial discharges (PD) that occur in electrical insulation systems (EIS) when stressed by repetitive voltage impulses generated from electronic power devices. Typical applications are EIS belonging to apparatus driven by power electronics, such as motors, inductive reactors and windmill generators. Excluded from the scope of this technical specification are:
- methods based on optical or ultrasonic PD detection,
- fields of application for PD measurements when stressed by non-repetitive impulse voltages such as lightning impulse or switching impulses from switchgear.
The principal changes with regard to the previous edition concern the addition of:
- an Introduction that provides some background information on the progress being made in the field of power electronics;
- impulse generators;
- PD detection methods;
- a new informative Annex C covering practical experience obtained from round-robin testing (RRT);
- example of noise levels, as shown in new informative Annex D.

Presents the important material properties for polymeric materials used in outdoor insulation and, where applicable, lists the standardised test methods including the minimum requirements. If no standardised tests are available, then test methods reported in literature are summarised. This report is valid for insulating materials used in outdoor high voltage electrical applications with a system voltage greater than 1000 V a.c. having polymeric insulation including also such applications where the housing is an integral part of the devices e.g. in surge arrestors and cable terminations. The scope of this report is limited to the materials only. The performance of insulators in service depends on several factors such as the type of material, the design, environmental conditions etc. Consequently, the choice of materials that fulfil the requirements listed below is a necessary condition but does not guarantee satisfactory performance when used in outdoor insulation

Gives requirements additional to those in IEC 60243-1 for the determination of the electric strength of solid insulating materials under 1,2/50 ms impulse voltage stress.

Gives requirements additional to those in IEC 60243-1 for the determination of the electric strength of solid insulating materials under direct voltage stress.

Gives test methods for the determination of the short-time electric strength of solid insulating materials at power frequencies between 48 Hz and 62 Hz. It does not consider the testing of liquids and gases.

IEC/TS 61251:2008(E) explains many of the factors involved in voltage endurance tests on electrical insulating materials and systems. It describes the voltage endurance graph, lists test methods illustrating their limitations and gives guidance for evaluating the a.c. voltage endurance of insulating materials and systems from the results of the tests. The terminology to be used in voltage endurance is defined and explained. It should be emphasized that where this technical specification is concerned with materials, the results may not be directly applicable to the performance of insulating systems. Voltage endurance tests are used to compare and evaluate insulating materials with regard to their various applications in electrical systems. Determining the ability of electrical insulating materials and systems to endure a.c. voltage stress is complex. The results of voltage endurance tests are influenced by many factors so this technical specification should only be considered as an attempt to present a unified view of voltage endurance for simplified planning and analysis. Some documents for the various practical cases exist and others are being developed. The main changes with respect to the previous edition are listed below:
- extension of the scope to cover electrical insulating material and insulation systems;
- removal of references to short time dielectric breakdown strength measurements as an indicator of voltage endurance.

applies to electrical equipment, regardless of voltage, containing an insulation system, which is - connected to an electronic power supply, and - requires an evaluation of insulation endurance under repetitive voltage impulses. This standard proposes a general test procedure to facilitate screening of electrical insulation systems (EIS) and to achieve a relative evaluation of insulation endurance under conditions of repetitive impulses.