Abstract: A high-Tc superconducting (HTS) power cable is considered to be a major candidate for the bulk power transmission device in the future. The HTS power cable with a cold dielectric type electrical insulation system can make the outer diameter of the HTS cable compact in order to replace the conventional XLPE cable laid in underground ducts. Therefore, establishment of the electrical insulation design, HV testing and evaluation methods is the most important in the realization of the HTS power cable. From these viewpoints, the electrical insulation design method and determination of testing voltages for a 500-m HTS power cable constructed for verification tests are discussed, and the result of the various tests are described in this paper.

Abstract: MV underground cable failures have been contributing to some 60% of annualized SAIDI for a number of years. Bulk of the reliability issues originated from MV underground cable joint failures. Special programs focused on skilled development of jointer and VLF Testing of cables were implemented over the last few years. Despite some early success, this approach is increasingly seen as being not sustainable as the fundamental issue of cable joint reliability and subsequent choice of cable joint technology is still unresolved. The choice of joint technology for MV underground cables has been a subject of much debate in the local industry in the midst of the growing evidence that the existing cable joint design is not performing well enough under the local operating environment. The approach towards seeking the long-term solution to the choice of cable joint technology is to conduct special performance-based laboratory testing. The methodology and tests are so designed as to expose the selected cable joints to extreme operational conditions and environment. Identified cable joint technologies and respective brands will later be further exposed to “extended field trials” before any standardization decision is made. This paper discusses the approach, methodologies and initiative in managing improvement effort of MV underground cable joint

Abstract: Publisher Summary This chapter presents the development and testing results of the 10-m long HTS power cable. A 10-m long, 3-phase, 10.5 kV/1.5 kA HTS power cable system has been built and tested. The warm dielectric cable includes 3 single-phase HTS cables using different winding schemes. The critical current of the cable is more than 2800 A and the total joint resistance of the conductor is less than 0.12 μΩ at 74 K. The AC loss measurements show the loss is less than 0.85 W/m at 74 K and 1.5 kA rms /50 Hz. Critical current of the HTS cable is more than 2800 A which exceeds the designed target. Long-time operation and thermal cycle tests indicate that the performance of the cable is stable. The joint resistances and ac losses of cable conductors are very low. This proves that joint weld technique and the methods to reduce AC losses of cable are very useful. The tests of HTS cable indicate that the design and development are successful.

Abstract: A 3-phase 10.5kV,1.5kA HTS cable 75m long under development will be put into trial-operation at the end of 2004.This paper analyses the distribution of the electric field of the 75m long HTS cable and presents design,process and testing of the overall insulation system.Pre-fabrication of insulation system for connection and termination was completed on a cable model consisting of cable, connection and termination imitating the real cable system and the voltage test was made on the cable system. During the 15kV AC voltage test,the PD measurement of the cable is less than 1pC.The model cable and cable system passed the 35kV AC voltage test.

Abstract: High voltage and high current testing methods for a very low frequency (VLF) composite bushing is presented. These measurements are performed at the Edgar Beauchamp High Voltage Test Facility (EBHVTF) in Dixon, California.