IEC 61788-17-2021 pdf free

IEC 61788-17-2021 pdf free.Superconductivity – Part 17: Electronic characteristic measurements – Local critical current density and its distribution in large-area superconducting films.
This part of IEC 61788 specifies the measurements of the local critical current density () and its distribution in large-area high-temperature superconducting (HTS) films by an inductive method using third-harmonic voltages. The most important consideration for precise measurements is to determine J at liquid nitrogen temperatures by an electric-field criterion and obtain current-voltage characteristics from its frequency dependence. Although it is possible to measure J in applied DC magnetic fields [20] [21], the scope of this document is limited to the measurement without DC magnetic fields
This technique intrinsically measures the critical sheet current that is the product of 4 and the film thickness d. The range and measurement resolution for 4c1 of HTS films are as follows.
— Jd: from 200 A/rn to 32 kA/m (based on results, not limitation).
— Measurement resolution: 100 AIm (based on results, not limitation).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
IEC 60050-815, International Electrotechnical Vocabulary — Part 815: Superconductivity (available at <http://www.electropedia.org>)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-815 apply. some of which are repeated here for convenience.
ISO and IEC maintain terminological databases tor use in standardization at the following addresses:
• lEG Electropedia: available at http://www.electropedia.org!
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 critical current maximum direct current that can be regarded as flowing without resistance practically
4 Requirements
The critical current density is one of the most fundamental parameters that describe the quality of large-area HTS films. In this document, J and its distribution are measured nondestructively via an inductive method by detecting third-harmonic voltages L’3cos(3, + 0). A small coil, which is used both to generate AC magnetic fields and detect third-harmonic voltages. is mounted just above the HTS film and used to scan the measuring area. To measure
precisely with an electric-field criterion, the threshold coil currents ‘th’ at which (.13 starts to emerge, are measured repeatedly at different frequencies and the E-J characteristics are determined from their frequency dependencies.
The target relative combined standard uncertainty in the method used to determine the absolute value of .f is less than 10%. However, the target uncertainty is less than 5% for the purpose of evaluating the homogeneity of 4 distribution in large-area superconducting thin films.IEC 61788-17 pdf download.