• Proceedings of the KIEE Conference
• /
• 1996.07c
• /
• pp.1828-1830
• /
• 1996

In this study, We developed the optical fiber incorporated high-voltage underground power cable which is combined optical fibers with conventional high-voltage underground power cable. Optical-Unit that optical fiber is inserted in stainless tube is tested, and we got good results enough to safe optical fibers. Also we put the optical fiber incorporated high-voltage underground power cable to the test of electrical characteristics and optical characteristics, we knew that the electrical characteristics were the same characteristics as conventional high-voltage underground power cable and the transmission loss change was almost zero.

• Journal of Hydrogen and New Energy
• /
• v.21 no.3
• /
• pp.149-157
• /
• 2010

The electromagnetic characteristics of FCEVs (fuel cell electric vehicles) are much different from the existing combustion engine cars as well as hybrid, plug-in-hybrid, and pure electric vehicles due to the high voltage/current generated by a fuel cell stack which uses a compressed hydrogen gas reacted with oxygen. To operate fuel cell stack efficiently, BOP (Balance of Plant) is essential. BOP systems are used many not only for motors in water pump, air blower, and hydrogen recycling pump but also inverters for these motors. Since these systems or components are connected by high voltage cables, EMC (Electromagnetic compatibility) analysis for high voltage/current cable is the most important element to prevent the possible electric functional safety errors. In this paper, electromagnetic fields of high current/voltage cable for FCEVs is studied. From numerical analysis results, time harmonic magnetic field strength of high current/voltage cable have difference of 20～28 dB according to phase. EMI result considered ground effect of FECV at 10 m shows difference of 14.5 dB at 30 MHz and 2.8 dB at 230 MHz compared with general cable.

• Proceedings of the KIEE Conference
• /
• 2004.11b
• /
• pp.63-65
• /
• 2004

The recent advancement in the power electronic technique has increased the use of induction motor fed by inverter using high-frequency switching devices. Also the tendency is toward larger size and higher voltage. Therefore, The IGBT (Insulated-Gate Bipolar Transistor) that is high switching frequency element has been using increase. But, The switching surge voltage was occurred by high switching frequency of inverter has appeared a voltage doubling in the motor input terminal due to mismatching of cable characteristic impedance and motor characteristic impedance. Actually, The Switching surge voltage became the major cause to occur the insulation failure by serious voltage stress in the stator winding of induction motor. The short during rise time of switching surge and cable length is increased, the maximum transient voltage seen at the motor terminals increases. In this paper, Analyzed switching surge transient voltage of power cable pulling is used EMTP(Electromagnetic Transient Program) at the induction motor terminal and in cable.

• Corrosion Science and Technology
• /
• v.18 no.4
• /
• pp.117-120
• /
• 2019

Considering the tendency of development of electrification vehicles, development and verification of new evaluation technology is needed because of new technology applications. Recently, as the battery package is set outdoors of an electric vehicle, such vehicles are exposed to corrosive environments. Among major components connected to the battery package, rust prevention of high-voltage cables and connectors is considered the most important issue. For example, if corrosion of high voltage cable connectors occurs, the corrosion durability assessment of using an electric vehicle will be different from general environmental corrosion phenomena. The purpose of this study is to investigate the corrosion mechanism of high voltage cable connectors of an electric vehicle under various driving environments (road surface vibration, corrosion environment, current conduction by stray current, etc.) and develop an optimal rust prevention solution. To improve our parts test method, we have proposed a realistic test method to reproduce actual electric vehicle corrosion issues based on the principle test.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2003.11a
• /
• pp.27-30
• /
• 2003

Recently, on power system, it is used to high voltage of transmission and distribution due to safe power supply and have high quality and insulation in order to satisfy excellent insulator. Thus, according to underground of high voltage cable, is occurred break down by ground short. Therefore, it is used to high quality XLPE power cable to interrupt instantaneous voltage drop. If it appear inner defect for cable whose have high quality and insulation, it is reduced rapidly due to concentration of electrical field. After assemble to manufacture, in order to inspect cable condition, it is decided much inspection standard. In this paper, In inner defect of assembling cable at manufacture, for measure the variation of insulation condition by void. it tested the variation of insulating characteristics, using $\phi$-q-n distribution variation in partial discharge experiment.

• Transactions on Electrical and Electronic Materials
• /
• v.7 no.5
• /
• pp.224-229
• /
• 2006

Many studies have been done on the application of residual charge measurement in cable degradation diagnosis. In this paper, the behavior of residual charges measured with water-tree degraded XLPE sheets and cable are discussed. At charge injection process, the charge is injected by applying dc voltage as a conventional method, suddenly cut-off ac voltage or impulse voltage. Therefore the residual charge is influenced by the applying process. At charge release process, transient dc current flows when applying ac high voltage and also ac high voltage superimposed to dc low voltage. From the results, new diagnosis method is suggested.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1488-1489
• /
• 2007

This paper described the current rating methodology of high voltage connectors used for high efficient vehicles. Typically, temperature rise at rated current has been used to rate power contacts in automotive connector. However, for automotive applications, they are required to meet severe environmental conditions and high connector reliability. Therefore, it is very important to rate correctly an allowable current of automotive connector. We have measured the contact characteristics through current cycling at room temperature and at high temperature, as well as temperature rising and current carrying capacity by de-rating. From the above results, we have developed high reliable contacts with about 80 Amperes.

• Proceedings of the KIEE Conference
• /
• 1994.07b
• /
• pp.1652-1654
• /
• 1994

The Extra-high voltage XLPE cable is characterized by low transmission loss, large capacity, and high reliability. Conventionally, for XLPE cables of l54kV and above, aluminium sheath was used to be moisture barrier (thus preventing water tree deterioration of the insulation) and to protect cable core from physical stresses. However, as transmission capacity of the cable increases, so does the cable diameter and the corresponding aluminium sheath outer diameter and thickness. As a result, eddy-current loss in the sheath is increased, limiting the maximum current capacity of the cable itself. As an alternative to aluminium sheath, we have adopted stainless steel sheath with non-magnetic properties and a large resistivity, The new XLPE cable with stainless-steel sheath (CSZV cable) has drastically reduced eddy-current loss in the sheath.

• Journal of Electrical Engineering and Technology
• /
• v.9 no.4
• /
• pp.1369-1374
• /
• 2014

Most accidents of medium-voltage cables installed in nuclear power plants result from the initial defect of internal insulators or the initial failure due to poor construction. However, as the service years of plants increase, the possibility of cable accidents is also rapidly increases. This is primarily caused by electric, mechanical, thermal, and radiation stresses. Recently, much attention is paid to the study of cable diagnoses. To date, partial discharge and Tan${\delta}$ measurements are known as reliable methods to diagnose the aging of medium-voltage cables. High frequency partial discharge measurement techniques have been widely used to diagnose cables in transmission and distribution systems. However, the on-line high frequency partial discharge technique has not been used in the nuclear power plants because of the plant shutdown risk, degraded measurement sensitivity, and application problems. In this paper, the partial discharge measurement with a portable device was tried to evaluate the integrity of the 4.16kV and 13.8kV cable lines. The test results show that the high detection sensitivity can be achieved by the high frequency partial discharge technique. The present technique is highly attractive to diagnose medium voltage cables in nuclear power plants.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.56 no.7
• /
• pp.1236-1240
• /
• 2007

In order to evaluate if the high-Tc superconducting(HTS) power cable is operating stably, the characteristics of the HTS power cable should be found out. The properties of HTS tapes by measuring the voltage with respect to the current can be archived. But, the HTS power cable is different from the case of HTS tapes. This method is invalid because of the electromagnetic fields caused by other HTS tapes. In this paper, the stability evaluation of the HTS cable was performed by the following procedure. First, the voltage-current characteristics of HTS tape were measured and the electromagnetic field distributions of the HTS power cable with the external magnetic field were analyzed. Second, the losses of the HTS power cable were calculated using the result of the measurement and the analysis. Finally, the stable operation of the HTS power cable was evaluated on the basis of the losses of the superconducting cable.