• Proceedings of the KIEE Conference
• /
• 1998.07d
• /
• pp.1425-1427
• /
• 1998

The thermal history of XLPE insulated cable during heating cycle voltage test specified by IEC 840 was examined by DSC(differential scanning calorimetry) method, of which the principal is on the basis of the phenomenon that the crystals in polyethylene are rearranged as it is annealed near/below the melting temperature. From the result, it can be estimated that XLPE insulation near the conductor was exposed at the temperature of about $100^{\circ}C$ with the electrical stress through the test.

• Proceedings of the KIEE Conference
• /
• 2004.04a
• /
• pp.12-14
• /
• 2004

Superconducting transmission power cable is one of interesting parts in power application using high temperature superconducting wire. One of import ant parameters in high-temperature superconduting (HTSC) cable design is transport current distribution because it is related with current transmission capacity and AC loss. In this paper, the transport current distribution at conducting layers was investigated through the analysis of the equivalent circuit for HTSC power cable with shield layer and compared with the case of without shield layer. The transport current distribution due to of the contact resistance and the pitch was improved in the case of HTSC power cable with shield layer from the analysis.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.12
• /
• pp.2065-2071
• /
• 2007

This paper suggests the harmonic effects on HTS(High Temperature Superconducting) power cable. HTS cable is regarded as not only one of the important countermeasure to supply high density power demand area, but also one of countermeasures greenhouse technology. However, with the development of digital society, the distribution line power is much contaminated with harmonics generated by various power electronic equipments. This paper describes how the HTS cable responds to the harmonic and increases AC losses caused by hysteresis phenomenon. EMTDC based harmonic simulation results are compared with AC loss measured values.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2003.10a
• /
• pp.281-283
• /
• 2003

High temperature superconducting power cable requires forced flow cooling. Liquid nitrogen is circulated by a pump and cooled back by cooling system. Typical operating temperature range is expected to be between 65K and 80K. Subcooler heat exchanger uses saturated liquid nitrogen boiling on the shell side to subcool the circulating liquid nitrogen stream that cools the HTS cable. The paper describes performance tests of the cooling system. The test items are heat exchanging performance of subcooler. pressure drop between supply and return lines, heat transfer coefficient inside former, cable cryostat heat leak and simulation of electrical load of HTS cable.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.1133-1135
• /
• 2004

Superconducting transmission power cable is one of interesting parts in power application using high temperature superconducting wire. One of important parameters in high-temperature superconducting (HTSC) cable design is transport current distribution because it is related with current transmission capacity and ac loss. In this paper, the transport current and magnetic field distributions at conducting layers were investigated through the analysis of the equivalent circuit for HTSC power cable with shield layer. The transport current distribution due to the pitch length and winding direction was improved in case of HTSC power cable with shield layer.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2002.08a
• /
• pp.64-68
• /
• 2002

According to the increasing power demand for the future construction of many underground cables will be required. However, construction of new ducts for power cables will be more difficult. Therefore, research work for realizing the high temperature superconducting(HTS) cable has advanced, where the development of electrical insulating system at cryogenic temperature is one of the major researches. For an electrical insulation design of HTS cable, it is important to understand not only breakdown but also partial discharge and dielectric loss($tan{\delta}$) in liquid nitrogen/paper composite insulation system. In this paper, we investigated breakdown characteristics in liquid nitrogen/paper composite insulation system for the application to HTS cable. And, we studied the breakdown characteristics of the multi-layer and butt gap of the insulation papers in liquid nitrogen. Also, we measured dielectric loss($tan{\delta}$) of the mini-model Cable made of TERLAM IPP.

• Proceedings of the KIEE Conference
• /
• summer
• /
• pp.424-426
• /
• 2004

As power demand increases gradually, the call for underground transmission system increases. But it is very difficult and high in cost to construct new ducts and/or tunnels for power cables in metropolitan areas. HTS (High Temperature Superconducting) cable has the several useful characteristics such as increased power density, stronger fields and/or reduced losses. Therefore HTS cable can allow more power to be moved in existing ducts, which means very large economical and environmental benefits. In these days, companies world-wide have conducted researches on HTS cable. A development project for a 22.9kV class HTS cable is proceeding at a research center and university in Korea. In this paper, we investigate the expected price of HTS cable to have a merit in viewpoint of economic aspect. First, life-cycle cost of conventional cable is calculated and based on this, the expected price of HTS cable is evaluated, which HTS cable is competitive against conventional cable.

• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.603_604
• /
• 2009

HTS tape is developed for the purpose of being applied to the power cable, motor and generator, etc. The resistance of conventional power cables is not changed a lot by over current condition. But HTS(High temperature superconductor)power cable has some different properties. The impedance of superconductor is changed due to the magnitude of current, temperature, and magnetic field. And the characteristics analysis of HTS power cable under many kind of fault conditions are important to apply real system. In addition the magnitude of over current is 10 times larger than rated current. In this paper, the characteristics of HTS power cable are analyzed when over current flows. Model cable used 2G wires was made and experimented. The results will be helpful to manufacture real HTS power cable.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2000.02a
• /
• pp.29-32
• /
• 2000

Superconducting transmission cable is one of interesting part in power application using high temperature super-conducting wire as transformance. One important parameter in HTS cable design is transport current distribution because it is related with current transmission capacity and loss. In this paper, we present the calculation theory of current distribution for multi-layer cable using the electric circuit model and in example, calculation results of current distribution and AC loss in each layer of 4-layer HTS transmission cable.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.18 no.1
• /
• pp.81-86
• /
• 2006

High temperature superconducting (HTS) power cable requires forced sub-cooled LN2 flow cooling. Liquid nitrogen is circulated by a pump and cooled back by cooling system. Typical operating temperature range is expected to be between 65 K and 77 K. The HTS power cable needs sufficient cooling to overcome its low temperature heat load. For successful cooling, the hydraulic characteristics of the HTS power cable must be well investigated to design the cables. Especially, the pressure drop in the cable is an important design parameter, because the pressure drop decides the length of the cable, size of the coolant circulation pump and circulation pressure, etc. This paper describes measurement and investigation of the pressure drop of the cooling system. In order to reduce the total pressure drop of the cooling system, the flow rate of liquid nitrogen must be controlled by rotational speed of the circulation pump.