R & D of Superconductive Cable in Japan

Abstract

Super-ACE (Superconducting AC Equipments) project was started in 2000 fiscal year as a national project to research and develop superconducting AC power equipment. This project goal to develop basic technologies for high temperature superconducting (HTS) cable, HTS fault current limiter (FCL), HTS magnet for reactor and transformer. Main subjects of the cable study are development of: HTS conductor having 3 kA rated current with 1 W/m AC loss, cooling technologies for a 500 m HTS cable with 1 kA rated current, and analytical study of integrated HTS power system. This paper describes major results of studies on the HTS superconductors, and outline and some results of verification test of 500 m cable.

Stability Analysis of HTS Power Cable With Fault Currents

“…In Japan, the Tokyo Electric Power Company (TEPCO) project (66 kV/1 kA/100 m, three cores, cold dielectric, [2001][2002] [6] and the Super-ACE project (77 kV/1 kA/500 m, single core, cold dielectric, [2000][2001][2002][2003][2004][2005] [7] have been successfully completed. A new HTS cable project in Japan was started in 2007; it is supported by the Ministry of Economy, Trade and Industry (METI) and the New Energy and Industrial Technology Development Organization (NEDO) [8], [9].…”

Demonstration and Verification Tests of 500 m Long HTS Power Cable

“…Liquid nitrogen (LN2) is pressurized and forced-circulated. The details of the HTS cable structure should be referred to the other paper [4]. Fig.…”

Insulation design method of cold dielectric type superconducting power cable and its verification tests

“…Verification and demonstration tests of a 500-m 77-kV 1000-A HTS cable had been implemented in Yokosuka area, CRIEPI, Japan, from November 2003 to March 2005 [4,5]. The tests aimed to clarify many technical problems such as pressure loss property, thermomechanical behavior at cool-down and warm-up periods, LN2 flow property, current flow property of superconductors.…”

“…Moreover, a cold dielectric (CD) type electrical insulation system which is a composite insulation system consisting of liquid nitrogen (LN2) immersed insulation paper tapes contributes to reduce the cable outer diameter, which makes relatively easier replacement from aged conventional power cables laid in underground ducts to the HTS cables [3,4]. However, electrical insulation design method for the CD type HTS cable has not been established yet.…”

“…This paper firstly proposes the design method of the electrical insulation layer of the CD type HTS cable. Then, the proposed method is applied to the insulation design of a 500-m HTS cable tested in CRIEPI [4,5]. Moreover test results of its long-term and overvoltage tests are described and the adequacy of the proposed design methods is discussed.…”