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Highlights the 35th Symposium on Electrical and Electronic Insulating Materials and Applications in Systems held in Tokyo, Japan on November 17-18, 2004. Topics discussed; Lecturers; Sponsors.

The peak current amplitude and front duration of lightning stroke current waveforms have conventionally been evaluated independently, and severe waveform assumptions are usually adopted in the current of lightning insulation designs. If lightning stroke waveform conditions are optimized, lightning insulation specifications of power facilities can be further rationalized. This paper proposes a new statistical technique to better evaluate lightning stroke current waveforms. The characteristics of lightning stroke current waveforms (i.e., that peak amplitudes correlate with front durations) are taken into account in this technique. The proposed technique was validated with various statistical tests. The front duration currently used in the design of the ultra-high-voltage system in Japan is 1.0 μs, but the potentially more accurate value of 1.7 μs was found when waveforms were evaluated with the proposed technique, and overvoltage analyses of gas-insulated switchgear show that overvoltages decrease with longer front duration. [ABSTRACT FROM AUTHOR]

Information about the twenty-second International Insulation in International Symposium on Discharge and Electrical Insulation in Vacuum (ISDEIV) which was held in Marsue, Japan on September 25-29, 2006 is presented. The symposium was hosted by the Vacuum Society of Japan. The conference was significantly altered to include developing vacuum microelectronics devices, surface modification technologies and other new vacuum plasma applications.

A new ac-dc comparator system of 20-1000 V has been developed at the National Metrology Institute of Japan (NMLJ) for the calibration of ac-dc thermal voltage converters (TVCs), which are used as national ac-dc transfer standards. The ac-dc transfer differences of high-voltage transfer standards were evaluated by a traditional step-up procedure. The voltage dependence of the ac-dc transfer difference was observed in the earlier step-up procedures over 300 V, as reported by the latest international intercomparison. The experimental results for high- voltage TVCs with several different range resistors at the NMU suggest that the voltage dependence may primarily be caused by input connectors of range resistors and the change in the resistance value of the resistor and TVC modules due to heating from resistors. This paper describes the voltage dependence improvement of ac-dc transfer differences over 300 V at the NMLJ. [ABSTRACT FROM AUTHOR]

The article reports on the mini-symposium on polymer nanocomposites held in Tokyo, Japan on September 28, 2005. It was sponsored by the Technical Committee on Dielectrics and Electrical Insulation and the Institute of Electrical Engineers of Japan. The meeting was convened by Toshikatsu Tanaka, Professor of Waseda University. Several research papers on polymer nanocomposites were presented during the symposium.

Information about several papers discussed at the meeting of IEC Working Groups (WGs) and Maintenance Team (MT) in the Japan Electrical Manufacturers' Association (JEMA) headquarters in Tokyo, Japan in April 16-20, 2007 is presented. Topics include the 10 IEC documents on coil insulation of rotating machines. It featured several machines including the IEC/TC112/WG3, IEC 60034-18-41/42, and PD inception voltage (PDIV)/PD extinction voltage (PDEV).

To mark 50 years of the DEIS, a series of review articles, written by recognized experts in various aspects of dielectrics and insulation, will be published in the Magazine during 2013. The first of these, also the first article in this issue, is ?Advances in Nanodielectric Materials Over the Past 50 Years? by Toshikatsu Tanaka from Waseda University, Japan, and Takahiro Imai from Power and Industrial Systems, Toshiba Corporation, Japan. Much information has been accumulated, and the applications of nanomaterials and nanotechnology are increasing rapidly. [ABSTRACT FROM AUTHOR]

The demonstration and verification tests of a 500 m High-Tc superconducting (HTS) cable were carried out at the CRIEPI laboratory in Yokosuka from March 2004 to March 2005. The HTS cable consisted of a cold dielectric core with nominal capacity of 77 kV and 1 kA that had an HTS shield layer. CRIEPI and Furukawa have conducted tests for investigating the basic properties of the cable and a long-term loading test for confirming 30-year operations. Moreover, we conducted an ‘over-loading test’ and a ‘cooling system fault test’ to investigate the reliability and safety of the cable. After all field tests, the cable was dismantled and taken away from the site to Furukawa's factory for internal inspection. No Ic degradation was found in the HTS conductor, but local degradation was seen in the HTS shield. These degradations might have arisen because protective layer for the shield did not have enough thickness but were within the acceptable range of about 5%. [ABSTRACT FROM AUTHOR]

Includes: Japan's First In-Grid Operation of a 200-MVA Superconducting Cable System [ABSTRACT FROM PUBLISHER]

Discusses the design of a novel device which has the ability to detect contamination on insulators on overhead transmission lines in Japan. Description of the device; Measurement of contamination on pilot insulators using the wiping method; Reference to studies conducted on measuring technologies in Japan and abroad.

Reports on the use of an optical fiber sensor developed in Japan in the thermal deterioration diagnosis of electrical insulation for power apparatuses. Key issues of interest; Analysis of pertinent topics and relevant issues; Implications on studies of dielectrics and electrical insulation.

Part III. Reports on the activities of several investigation committees relating to dielectrics and electrical insulation in the Institute of Electrical Engineers of Japan in 2004. Introduction of the application on nanocomposite materials to the field of dielectrics and electrical insulation; Key objectives of the institute in jump-starting a meeting on nanocomposites; Implications on studies of dielectrics and electrical insulation.