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SF6 gas is widely used as interrupting medium for disconnecting switch and circuit breaker in power system whose voltage is above 72kV or medium voltage. Global warming effect of SF6, however, is well known and emission of this gas is strictly limited by regulation. As for research to find out substitute for SF6 gas, many works have worked out. Gleitzes [1] compared with SF6 and N2 and found out characteristic...
New concept of paper-based devices (we call “paper analysis chip”) and inkjet printer-like analyzer for clinical diagnostics has been presented. We proposed new liquid-handling mechanisms realized on the paper chips. An original paper material of the chips (we call it “functional paper”) was made by a newly developed paper-making process with adding SAP (super absorbent polymer). By using demonstrate...
We are developing integration and installation technologies of on-site water-quality monitoring network based on the model-based design technique, which allows us to check the performance quickly without building prototypes from its element level (micro-fluidics, micro-TAS) to the network level. In this paper, we describe newly developed model-based simulation platform suitable for micro-fluidic devices,...
New concept of paper-based devices (we call “paper analysis chip”) and ink-jet printer-like analyzer for clinical diagnostics was presented. An original paper material of the chips (we call it “functional paper”) was made by a newly developed paper-making process with adding SAP (super absorbent polymer). The quite a new liquid handling mechanism with an active injection port by accumulation of the...
In a search for mineral oil substitutes, we investigated the characteristics of environmentally friendly silicone oil and ester oil. The electrical performance was assessed in terms of the breakdown, streaming electrification characteristics and the volume resistivity. The burning characteristics of each oil were also investigated. The temperature dependence of the breakdown voltage in an oil unit...
We have developed 120-GHz-band wireless equipment that can transmit 10-Gbit/s data signal over a distance of more than 5 km. In order to increase the output power of the120-GHz-band wireless equipment, we used a millimeter-wave amplifier that integrates 0.08-μm-gate-length InGaAs/InP composite-channel high-electron-mobility transistors. The output power of the wireless equipment becomes 16 dBm. The...
We are developing elemental technologies for next-generation high-speed wireless links for transmitting program materials in live broadcasts. In particular, we are developing a 10-Gbps forward error correction (FEC) system for transmitting multiplexed HD-SDI wireless signals in the 120-GHz-band. The system can send error-free 10-Gbps data transmissions over a distance of 3 km. This paper describes...
In this paper, we investigated temperature decay of thermal plasmas due to polymer ablation using the inductively coupled thermal plasma (ICTP) irradiation technique. The features of the ICTP are no contamination and good controllability compared to arc plasmas with electrodes. The Ar-ICTP was directly irradiated to the polymer bulk materials placed at downstream region of the thermal plasma. Spectroscopic...
In this paper, we present 10-Gbit/s wireless data transmission with FEC that is used for optical fiber data transmission. We evaluated the gains of coding by using a back-to-back data transmission system and compared them with those in outdoor data transmission experiments.
In many cases, the vacuum circuit breaker is used as the single-break, and investigation is not conducted so much about the double-break vacuum circuit breaker. So, we are investigating the relation between the post arc current and the voltage distribution ratio in the double-break vacuum circuit breaker. In this investigation, the post arc current and the voltage distribution ratio were measured...
It is important to comprehend the interruption phenomenon of contact materials for aiming at adaptation to high voltage of vacuum circuit breakers. Then, we carried out measurement of arc energy and anode surface temperature and observation of vacuum arc by using the vacuum chamber. Moreover, we made prototype of new contact materials that was based on these tests result. And these contact materials...
Biodegradable polymer plasticizers, polycaprolactone (PCL) and polybutylene succinate adipate (PBSA) were blended with starch ester (SE), and their thermal properties and dielectric properties such as electrical conductivity, complex permittivity, and AC breakdown strength were examined. As a result, it has become clear that SE blends with PCL and PBSA can be used as electrical insulating materials...
In this study, investigation of the insulation performances of the silicone oil as an insulating medium is studied with aim of realization of environmental friendly electric power apparatus, which is considered to be flame retardant. This investigation is searching for the streaming electrification characteristics when silicone oil flows in consideration of cooling of electric power apparatus. In...
We introduce in this paper the sensitivity of two UHF couplers, disc-type measuring electrode and loop-type measuring electrode embedded in an epoxy insulator, for detecting partial discharge (PD) and diagnosing GIS. Each of the couplers has sufficient performance for detecting the electromagnetic waves up to 8 GHz. The attenuation characteristic of electromagnetic waves is changed depending upon...
The authors have studied insulation diagnostic technique of gas-insulated switchgear (GIS) by UHF method. It is known that PD-induced electromagnetic wave is affected by a discontinuity part of impedance such as L-shaped structure, spacers and so on. In this paper, we experimentally investigated influence of L-shaped structure on propagation properties of PD-induced electromagnetic wave measured with...
The authors have studied insulation diagnostic technique of gas-insulated switchgear (GIS) by UHF method. In this paper, we investigated the effect of spacer type (metal flange type (MT) or bush type (BT)) on the propagation properties of PD-induced EM wave in GIS with UHF method. Low pass filtering process for cut-off frequency of TE11 mode was used to eliminate the higher order mode above TE11 of...
Polymer ablation phenomenon by thermal plasmas was fundamentally investigated using the inductively coupled thermal plasma irradiation technique. It is greatly important to understand interactions between a thermal plasma and polymer materials, for example, for design of low voltage and high voltage circuit breakers. In the present experiment, the Ar induction thermal plasma was directly irradiated...
Many of natural energy power generations create electricity of DC current. On the other hand, many of load sides consume DC converted from AC. Therefore, conversion loss and CO2 emission may be able to reduce by adopting DC distribution. However, the interruption on DC current becomes difficult because zero point which exists in alternate current doesn't exist. To achieve the interruption becomes...
This paper describes experimental results of flashover characteristics of a medium voltage insulator to support an insulated cable using an impulse voltage generator. This experiment is targeted for direct lightning strokes to a distribution line. The lightning impulse voltage is applied to a cross arm to represent the direct lightning stroke. A flashover on the insulator occurs from the arm to the...
Epoxy/alumina nanocomposites were newly prepared by dispersing 3, 5, and 7 weight % nano-scale boehmite alumina particles in a bisphenol-A epoxy resin. Dispersion of alumina particles in the nanocomposite specimen was observed by scanning electron microscopy (SEM). Flexural properties, dynamic viscoelasticity, permittivity, partial discharge (PD) resistance, and electrical breakdown time were investigated...
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