Award type：International academic award (Japan or overseas)  Country：Japan

Award type：Award from Japanese society, conference, symposium, etc. 

Award type：Award from international society, conference, symposium, etc.  Country：Japan

Award type：International academic award (Japan or overseas)  Country：China

Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

Country：Japan

Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

Award type：Award from Japanese society, conference, symposium, etc.  Country：Japan

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1002/tee.70073

Open Access

Web of Science

Scopus

Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Last author,　Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Institute of Electrical Engineers of Japan  

<p>The concept of carbon neutrality has attracted significant attention, leading to a growing demand for circuit breakers that can be installed in DC electric power systems. Our research group has proposed a safe, rapid, cost-effective, and compact circuit breaker that combines the high current-limiting performance of fuses with the high-speed interruption function of power semiconductors. The objective of this study is to further develop this device into a system that can be defined as a true “circuit breaker” by introducing a fuse exchanger using a linear motor. The integration of the exchanger within the circuit breaker enables three critical functions: reclosing the current path, interrupting small currents, and preventing fuse explosions. To achieve these functionalities, a feedback switching control method was developed and experimentally verified under high-voltage conditions.</p>

DOI： 10.1541/ieejias.145.506

Scopus

CiNii Research

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.35848/1347-4065/ade83b

DOI： 10.35848/1347-4065/ade83b

Scopus

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEEE Access  

In a bipolar voltage source converter-based multi-terminal DC (VSC-MTDC) system, the power flow of the positive and negative pole networks can be controlled independently. This advantage allows bipolar systems to maintain operation with only the healthy pole even in the event of DC faults. However, existing power flow control methods for bipolar systems do not include the optimal mode-switching of each converter’s operation and may not be sufficiently reliable during fault conditions. Thus, this paper proposes a new control scheme considering coordination between the poles and flexibility in power shifting. The proposed method consists of two steps: (a) a mode-switching method of converters to maintain DC voltage stability during converter trips and (b) an active power dispatch control method to enable power shifting from the faulty pole to the healthy pole, mitigating the risk of power surplus and ensuring a robust response to AC grid stability issues. The power assurance coefficient ω mass,i is defined as critical factor for determining the interpolar power dispatch. The simulation results show that an average transmission power outage of approximately 220 MW can be prevented during a single-pole trip while maintaining the operation within the rated VSC capacity when ω mass,i is set to 0.5. This highlights the effectiveness of the proposed method in maintaining the system reliability and stability. Overall, the proposed method enhances the transmission capability by maintaining the operation within the rated capacity, enabling interpolar power shifting, and mitigating the AC grid instability during fault conditions regardless of the bipolar configuration.

DOI： 10.1109/ACCESS.2025.3542740

Open Access

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Institute of Electrical Engineers of Japan  

<p>A method for estimating the internal pressure rise when ground fault occur inside power cable terminations has not been established yet because the pressure rise due to a ground fault is a fast phenomenon that occur within a few milliseconds. In this study, a mock-up experiment was conducted in order to reproduce the first peak of the pressure rise when a ground fault occurs, by burning explosives in the insulators used in 110kV class cable terminations. The experimental results were compared with numerical analysis result, which was solved by the equation of state considering the generation of shock waves. The maximum pressure at the mock-up experiment was 11.4MPa at 2.2ms. Compared to a numerical result with an initial pressure of 10MPa in the combustion gas region, the maximum pressure of the numerical analysis was 25% higher and the time was 0.27ms faster than the result of the mock-up experiment. The local pressure rise could be reproduced approximately by this analysis method. If the strain of the sample and fluid leakage could be reproduced in the model, more accurate analytical results could be obtained.</p>

DOI： 10.1541/ieejpes.145.417

DOI： 10.1541/ieejpes.145.417

Scopus

CiNii Research

Publisher：Plasma Physics and Technology  

Direct current (DC) facilities are increasing with the spread of renewable energy such as photovoltaic power generation. DC series arc may occur in poor contact or disconnecting in the facilities and cause fire incidents. This paper presents DC series arc generation experiments in air considering actual failure conditions, and Wavelet transformation analysis of the measured current waveform. Using the obtained results, a method of detection of arc generation in low-voltage DC facilities is proposed.

DOI： 10.14311/ppt.2025.1.34

Open Access

Scopus

Publisher：Electrical Contacts Proceedings of the Annual Holm Conference on Electrical Contacts  

Reliable and cost-effective DC circuit breakers (DC CBs) are essential for DC power systems. In a previous study, we developed a hybrid DC CB that utilizes a current-limiting fuse as the main path. Additionally, the commutation path incorporates a single IGBT and a contactor connected in series to suppress the voltage across the IGBT. However, its practical implementation faces challenges related to operational delay and speed. In this study, the limitations of using a typical contactor, a plate-plate contactor, is first verified. To address these challenges, two novel contactor designs is proposed: a hemisphere-plate contactor and a sliding contactor. These designs are expected to reduce the duration between the commutation and interruption, thereby providing a promising solution to ensure reliable fault current interruption in hybrid DC CBs.

DOI： 10.1109/HLM51652.2025.11278304

Scopus

Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEEJ Transactions on Electrical and Electronic Engineering  

The current-limiting fuse uses silica (SiO2)-sand as arc quenching medium to increase a current-limiting performance during the DC arc quenching process. In order to increase the current-limiting performance of the fuse, a detailed understanding of an arc resistance (Formula presented.) rise process is necessary. This paper first carried out a 1000 A DC Cu arc quenching experiment using the silica-sand to obtain transient change in (Formula presented.), morphology of the arc, and arc temperature (Formula presented.) during the arc quenching process. As a result, a current decaying increased (Formula presented.). The arc was maintained in the cavity surrounded by the fulgurite during the current decaying process. The temperature of Cu/SiO2 arc was 25–8 kK at a current region of 950–400 A during the arc quenching process. Second, we theoretically calculated an electrical resistivity (Formula presented.), and a thermal diffusivity (Formula presented.) as vapor properties for the Cu/SiO2 vapor mixture. As typical results, the admixing of the SiO2 vapor into the Cu arc less increased (Formula presented.) of the Cu/SiO2 vapor mixture at (Formula presented.) between 25 and 5 kK. The (Formula presented.) of the Cu/SiO2 vapor mixture drastically increased due to only decay in (Formula presented.). In contrast, the admixing of the SiO2 vapor into the Cu arc significantly increased (Formula presented.) at (Formula presented.) between 15 and 8 kK. The present results indicate that an increase in (Formula presented.) and consequent rise in thermal energy dissipation from the arc is the main role of the silica-sand vapor mixed with Cu arc in the DC fuse during the arc quenching process. The increased thermal energy dissipation due to the SiO2 vapor admixing further decreases (Formula presented.) to rapidly rise (Formula presented.) and (Formula presented.) during the arc quenching process. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

DOI： 10.1002/tee.24156

Web of Science

Scopus

Language：English   Publishing type：Research paper (international conference proceedings)  

EPP-24-078/SP-24-019/HV-24-080

Language：English   Publishing type：Research paper (international conference proceedings)  

EPP-24-091/SP-24-032/HV-24-093

Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.1109/IECON55916.2024.10905360

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

PE-24-171/PSE-24-171

Authorship：Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers  

Concerning DC fuses equipped with silica sand (SiO2) as an arc quenching material, the authors have proposed an additive installation of silicone resin (C2H6SiO) on a fuse-element surface to improve the limitation and interruption ability of high DC. This paper describes the additive effect of the silicone resin on the transient resistance of the arc that has formed during the DC interrupting process in a model fuse, based on the measurement result that the arc resistance markedly rises with the silicone mass coated on the fuse element. This phenomenon is subsequently explained as resulting from a thermal diffusivity of high-temperature C2H6SiO/SiO2/Cu vapor. In other words, the mixing of C2H6SiO decomposition vapor into the arc can promote vapor temperature decay through the higher thermal diffusivity, resulting in a rapid increase in the electrical resistivity of the vapor during the DC interrupting process.

DOI： 10.35848/1347-4065/ad7432

Open Access

Web of Science

Scopus

Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Proceedings of the 2024 International Conference on Sustainable Energy: Energy Transition and Net-Zero Climate Future, ICUE 2024  

Due to the advantage of the system operation reliability and flexibility, the bipolar multi-terminal high voltage dc (MTDC) transmission has attracted worldwide attention for the integration of offshore windfarms. However, majority of existing operation methods and dc power flow algorithms are designed to control the monopolar MTDC system. It is difficult to implement the conventional control method for the monopolar system into the bipolar system due to the difference in the characteristics of dc power flow control scheme between the two configurations. Therefore, this paper proposes an operation method of the bipolar MTDC system composed of the dc power flow control scheme and mode-switching method. As a simulation result, the proposed method can realize the power sharing between each VSC and reduce the impact of the active power fluctuation on the AC grid connected to the system even when the single-pole trip occurs in the bipolar MTDC system.

DOI： 10.1109/ICUE63019.2024.10795532

Scopus

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

EPP-24-067/SA-24-035/SP-24-008

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

EPP-24-068/SA-24-036/SP-24-009

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

EPP-24-063/SA-24-031/SP-24-004

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

EPP-24-064/SA-24-032/SP-24-005

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

EPP-24-066/SA-24-034/SP-24-007

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Institute of Electrical Engineers of Japan  

DOI： 10.1541/ieejjournal.144.504

CiNii Research

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：The Institute of Electrical Engineers of Japan  

<p>For the realization of carbon neutrality and an advanced information society, we have previously developed a novel current-limiting circuit breaker composed of a fuse, a power semiconductor and a fuse exchanger. However, its feasibility has been confirmed only for fault current interruption in a low voltage range of 100-500V. In this paper, the current-limiting circuit breaker was successfully used for fault and load current interruption at DC 1.5kV, thus demonstrating the high versatility of the circuit breaker.</p>

DOI： 10.1541/ieejias.144.502

Scopus

CiNii Research

Publisher：Journal of Physics D Applied Physics  

A current-limiting and consequent direct current (DC) arc interruption requires an increase in arc resistance r a r c for a DC fuse. Flattery silica (SiO<inf>2</inf>) sand has been used as an arc quenching medium in fuses for decades. However, there are few reports about a novel arc quenching medium which enables more r a r c increases compared to flattery SiO<inf>2</inf> sand. This paper uniquely selected a novel arc quenching medium based on the following material properties: (1) electrical resistivity and thermal conductivity in the solid phase, (2) the possibility of r a r c increasing in the gas phase, (3) the possibility of electrical insulation after re-solidification, and (4) the cost of materials. As a result, we originally selected a powder mixture of silicon-nitride (Si<inf>3</inf>N<inf>4</inf>) and flattery SiO<inf>2</inf> sand as a promising novel arc quenching medium. Therefore, DC interruption experiments were performed using a Si<inf>3</inf>N<inf>4</inf>/flattery SiO<inf>2</inf> sand powder mixture under different Si<inf>3</inf>N<inf>4</inf> concentration conditions. As a result of 1000 A DC arc quenching experiments, the utilization of Si<inf>3</inf>N<inf>4</inf> powder with the flattery SiO<inf>2</inf> sand successfully increased the arc resistance r a r c during the arc quenching process. The increasing Si<inf>3</inf>N<inf>4</inf> concentration exhibited a further increase in r a r c during the arc quenching process. As a result of the r a r c increase, the arc quenching time was significantly shortened to 30 ms for 30 wt.% Si<inf>3</inf>N<inf>4</inf> conditions from 54 ms for the SiO<inf>2</inf> sand conditions. In addition, utilization of Si<inf>3</inf>N<inf>4</inf> powder achieved high insulation resistance over few MΩ after DC arc interruption. The above results clearly indicate that utilization of Si<inf>3</inf>N<inf>4</inf> powder with flattery SiO<inf>2</inf> sand can increase the DC interruption performance of the fuse.

DOI： 10.1088/1361-6463/ad2ab2

Open Access

Web of Science

Scopus

Publisher：Journal of Physics D: Applied Physics  

Recently, electric power equipment manufacturers released a joint statement with the aim of developing high-voltage electrical equipment completely free of fluorinated gases such as fluoroketones and fluoronitriles, which are considered as alternatives to S F 6 and artificially produced compounds of F. This paper considers air as a typical gas present naturally in the environment to investigate its high-temperature properties, including an air mixture with C 2 F 4 vapor injected from a polytetrafluoroethylene nozzle, for application as an arc-quenching medium in a high-voltage circuit breaker equipped with a nozzle. Chemical composition results for the reaction products at 300-3000 K show that the admixture of C 2 F 4 vapor causes a decrease in the molar number of O 2 contained in the air, owing to the production of O-containing compounds such as C O 2 and C O . Additionally, the results reveal that the admixture of C 2 F 4 vapor lead to the production of C F 4 as the predominant F-containing compound. Furthermore, the boundary condition for O 2 production in terms of O 2 molar number X O 2 and C 2 F 4 molar number X C 2 F 4 is formulated. Such evaluation of the mixture composition enables the determination of a reduced effective collision ionization coefficient α ˉ / N and a critical reduced electric field strength E c r / N , resulting in α ˉ / N = 0. The strength E c r / N for the mixture with 30%-100% C 2 F 4 molar fraction rises to approximately 150 Td (1 Td = 1 × 10 − 21 V m2) over 300-3000 K, which is 20-50 Td higher than that for high-temperature air unmixed with C 2 F 4 vapor. The variation in E c r / N is discussed in terms of predominant electron impact processes and the electron energy distribution function in the mixture.

DOI： 10.1088/1361-6463/ad2a15

Open Access

Web of Science

Scopus

Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.1109/IECON55916.2024.10905360

Web of Science

Scopus

Authorship：Last author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of Physics D: Applied Physics  

To improve the interruption capacity of a current-limiting fuse, a detailed diagnosis of the spatial electrical conductivity distribution inside the fuse arc under the current limiting phase around current zero is required, because this distribution determines the distribution of transient recovery voltage inside the fuse. However, well-established methodologies applicable to fuse arcs are lacking, so the spatial distribution remains unknown. This study presents a borescope-integrated spectroscopic system that simultaneously obtains single-shot recordings of the axial distributions of the electron density and arc temperature in the fuse arc just before extinction. Combining the electron densities and arc temperatures, we can identify the fuse arc composition and hence calculate the axial electrical conductivity distribution under the first Chapman-Enskog approximation. The electrical conductivity provided by this systematic methodology includes no large uncertainties, thus demonstrating its superiority against previous estimation methods of the electrical conductivity.

DOI： 10.1088/1361-6463/acf9b2

Open Access

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of Physics D: Applied Physics  

Most high-power electric fuses installed in DC distributions of automobiles employ silica sand (chemical formula SiO2) as arc quenching material to implement the limitation and subsequent interruption of high direct currents. This paper on arc quenching material describes the effects of the addition of silicone resin (chemical formula C2H6SiO) on SiO2 sand, based on the resistance of an arc discharge in SiO2 vapor mixed with silicone resin vapor. The measurement results obtained for the fuse operation of a model electric fuse show that the addition of silicone resin, e.g. an even coating of silicone resin on the surface of a Cu fuse element, attains a shorter arc quenching time. This phenomenon is subsequently explained based on the rise effect of an arc column resistance achieved by mixing with silicone vapor decomposition. The chemical compositions of high-temperature SiO2 vapor mixed with C2H6SiO vapor decomposition are evaluated to show the predominant chemical species at 30 000 K-5000 K for several C2H6SiO vapor concentrations, X C H . The results obtained for X C H of 10%-50% reveal that a H atom originating from C2H6SiO is present at high molar fractions above 0.1 over a wide temperature range of 12 000 K-5000 K. Further evaluations of the electrical resistivity ρ R for the high-temperature vapor show that mixing with C2H6SiO vapor contributes to a rise in ρ R at temperatures of 10 000 K-6000 K. A contribution analysis of the ρ R reveals that the rise effect of the ρ R is accomplished chiefly by the presence of a H atom that has dissociated from C2H6SiO.

DOI： 10.1088/1361-6463/acee92

Open Access

Web of Science

Scopus

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEEJ Transactions on Electrical and Electronic Engineering  

This paper was arranged a polymer cylinder around a Cu fuse-element to increase both an arc resistance (Figure presented.) during a DC arc quenching process and an insulation resistance (Figure presented.) after the DC arc quenching. The used polymer cylinder equips a narrow-section with a width (Figure presented.) made from the polymer. A position of the narrow-section was around an arc-ignition point of the Cu fuse-element. Silica-sand (SiO2-sand) was filled inside the polymer cylinder. Then, a damping DC with a prospective peak of 1000 A was energized to the Cu fuse-element. As an experimental result, (Figure presented.) was successfully increased with (Figure presented.) of the narrow-section. In addition, the rise in (Figure presented.) of the narrow-section also increased (Figure presented.) to more than 10 (Figure presented.) under the DC 1000 V application after the arc quenching. In order to interpret (Figure presented.) rise and high (Figure presented.) under the polymer cylinder arrangement, chemical composition, an electrical resistivity (Figure presented.), and a thermal diffusivity (Figure presented.) of Cu/SiO2/Polymer vapor mixture was also calculated. Based on the experimental result and calculation result, (Figure presented.) rise can be interpreted based on rise in (Figure presented.) and (Figure presented.) due to the polymer vapor admixing into Cu/SiO2 vapor mixture. In addition, increasing (Figure presented.) can also be interpreted by the polymer ablation of the narrow-section of the cylinder. The results are useful to further increase the interruption capacity of the DC fuse. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

DOI： 10.1002/tee.23911

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Scopus

Authorship：Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：English   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (bulletin of university, research institution)  

Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Proceeding - ELTICOM 2022: 6th International Conference on Electrical, Telecommunication and Computer Engineering 2022  

Power protection devices such as gas circuit breaker and current limiting fuse are key component for safety usage of electric system. During fault current breaking process high temperature arc can be formed inside these devices. The arc breaking is neccessary to achieve current interruption. High temperature gas properties of arc is very important factor to simulate the arc breaking process and to design the protection device. This paper briefly introduces calculation procedure of gas properties and discuss the importance of gas property analysis using the arc inside the limiting fuse as typical example. In addition, it is also introduced the relationship between gas property analysis and the quentum chemical calculation as recent trends.

DOI： 10.1109/ELTICOM57747.2022.10038272

Scopus

Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Lead author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.1109/ICEPE-ST51904.2022.9757094

Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

DOI： 10.1109/ICEPE-ST51904.2022.9756991

Language：Japanese   Publisher：ICEPE-ST 2022 - 2022 6th International Conference on Electric Power Equipment - Switching Technology  

It is strongly desired for DC fuse that a compatibility of high arc resistance(rarc) during a DC arc interruption and high insulation resistance(Rins) after the DC arc interruption. This paper describes a trial experiment of DC arc interruption under following conditions. (1) Copper(Cu)-element arrangement in silica-sand filling space(designated as "S-wo"), (2) Arrangement of a polymer fuse-case filled with the silica-sand around the Cu-element(designated as "S-CaseA"), and (3) Arrangement of a polymer narrow-section around an arc-ignition point of Cu-element in the silica-sand filled fuse-case(designated as "S-CaseB"). The damping DC with a prospective peak of 1000 A was energized to the Cu-element to ignite the DC arc. As a result, the compatibility of high rarc and high Rins was successfully achieved only under the S-CaseB condition. These high rarc and high Rins can be interpreted from the shrinking of arc conductive diameter by the silica-sand filled inside the fuse-case and formation of insulation layer by the ablation of the polymer-narrow section.

DOI： 10.1109/ICEPE-ST51904.2022.9757094

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Scopus

Language：Japanese   Publisher：ICEPE-ST 2022 - 2022 6th International Conference on Electric Power Equipment - Switching Technology  

With regard to HFO-1234yf mixed with CO2 as a buffer gas, this paper describes dielectric breakdown properties such as an electron attachment coefficient and a critical reduced electric field strength Ecr/N at 300-3000 K. First, this paper covers predominant molecular products through thermal dissociation and combination reactions for 20%HFO-1234yf/80%CO2 gas mixture. Secondly, dielectric breakdown properties of the mixture in consideration of the predominant gaseous molecular products are described to show that Ecr/N is 87-100 Td at 300-3000 K.

DOI： 10.1109/ICEPE-ST51904.2022.9757102

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Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEEJ Transactions on Electrical and Electronic Engineering  

Concerning DC arc quenching phenomenon in silica sand filling space, we have proposed a new method for raising an arc column resistance (rcol) by use of polymer-material arrangement. This paper reveals physical factors for rcol rise on the bases of experimental results using the following cylinders made of: (i) Quartz (SiO2) and (ii) PMMA ((C5H8O2)n) with various inner diameters ϕ. For ϕ = 2 mm case, rcol measured for a PMMA cylinder arrangement indicated higher rcol at low current region, while almost same rcol around current peak. For ϕ = 3 mm case, rcol for the PMMA cylinder was lower than rcol for the quartz case at high current region, while almost comparable between these conditions at low current region. For ϕ = 5 mm case, rcol were almost same during the arc quenching process. To discuss the effect of the rcol rise, the followings were also performed: (i) observation of cylinders after arc quenching and (ii) calculation of the electron density of SiO2/Cu or PMMA/SiO2 mixture vapors. It is concluded that, at high current region, rcol can increase due to the shrinking of the arc conductive diameter caused by the cylinder hole and the silica sand filled inside the cylinder hole. On the other hand, the admixing of the PMMA ablation vapor increases rcol at low current region in the present experiment. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

DOI： 10.1002/tee.23462

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Scopus

Authorship：Lead author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Last author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IEEJ Transactions on Electrical and Electronic Engineering  

In this study, experiments pertaining to direct current (DC) interruptions are performed in an arc-quenching chamber filled with silica sand. First, the arc column resistance is measured during DC arc-quenching to demonstrate the elementary aspects of the arc in the silica-sand-filled space. Subsequently, an arrangement comprising a polymer cylinder between electrodes in the silica-sand-filled space is proposed to increase the arc column resistance during DC arc-quenching. A polymethyl methacrylate (PMMA) cylinder is used in the experiments. Measurement results indicate that the arrangement of the PMMA cylinder causes the arc column resistance to increase approximately twofold in comparison with the no-PMMA cylinder arrangement. Finally, the effect of increasing the arc column resistance is discussed in terms of PMMA and silica vapor. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

DOI： 10.1002/tee.23368

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Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Journal of Physics D: Applied Physics  

For a high voltage SF6 circuit breaker equipped with a boron nitride (BN)-filled polytetrafluoroethylene ((C2F4)n nozzle, the predominant reaction products in a high-temperature SF6 mixture with vapor decomposition of C2F4 and BN at temperatures of 300-3000 K are determined based on calculations of equilibrium composition. The calculation is performed by considering the molecular products obtained by chemical reactions with boron atoms (e.g. BN, BS, BC, BF, BF2 and BF3), nitrogen atoms (e.g. N2, N3, CN, NS, NF, NF2 and NF3) and carbon atoms (e.g. CS, CS2, C2F4, CF2, CF3 and CF4). The results obtained for the C2F4-BN molar fraction X CFBN of 20%-80% reveal that BF3, N2 and CF4, the molecules originating from the nozzle material, are produced at high molar fractions over a range of 300-3000 K. Such an evaluation of the gas composition allows the derivation of a reduced collision ionization coefficient α/N and a reduced electron attachment coefficient η/N of the gas, considering various electron impact processes such as BF3 + e BF2 + F- and CF4 + e CF3 + F-. The evaluation subsequently enables us to determine a critical reduced electric field strength causing . The results suggest that the decomposed C2F4-BN mixture at XCFBN of 80% causes the reduction of to 110 Td in the range of 1000-2000 K at a gas pressure of 1.0 MPa. This strength is 20 Td lower than that determined separately for the SF6 gas mixture with only 80% C2F4 vapor decomposition, because of the CF4 molar fraction reduction in the SF6/C2F4-BN mixture.

DOI： 10.1088/1361-6463/abda80

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Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Institute of Electrical Engineers of Japan  

<p>DC arc interruptions were carried out under following two conditions: (1) silica sand filling without any cylinder arrangement (designation: Silica), and (2) The silica sand filling with a quartz cylinder arrangement (designation: SilicaQuartz). During these experiments, optical emission spectroscopy (OES) measurements were carried out to investigate an arc column resistance rise by the quartz cylinder arrangement. An arc temperature <i>T</i> and a Cu vapor concentration were evaluated from the OES results. As a result, <i>T</i> were measured to be around 24 kK for the Silica condition and 17kK for the SilicaQuartz condition at a current peak. The Cu vapor concentration under the Silica condition gradually decreased with <i>T</i> decaying. On the other hands, the quartz cylinder arrangement in the silica sand filling space drastically decreased the Cu vapor concentration during an arc-quenching process. This drastic decrease in the Cu vapor concentration is one of key factors to increase <i>r</i>_col under the cylinder arrangement in the silica sand filling space. This verification result can be useful to increase an interruption capacity of fuse.</p>

DOI： 10.1541/ieejpes.141.725

Scopus

CiNii Research

Language：English   Publishing type：Research paper (scientific journal)   Publisher：The Institute of Electrical Engineers of Japan  

<p>The gases used in high voltage electric power equipment are required to withstand against an externally applied electric field strength. It is therefore essential to find out the electrical insulation strength of the gas. However the high temperature gas formed after the current zero through the arc extinction process in a circuit breaker shows different insulation strengths from that at room temperature, because the high temperature gas consists of various molecular products different from the original gas at room temperature. The CF₃CFCH₂ (called as HFO-1234yf) at room temperature is known to have a remarkable electrical insulation property similar to SF₆. After describing the products generated in CO₂ gas mixture with O₂ and HFO-1234yf decompositions at temperatures below 3000K, this paper mentions dielectric breakdown properties of the mixtures in view of the molar fractions of the molecular products. Discussions are furthermore made to compare dielectric breakdown properties of CO₂ gas and CO₂/O₂ gas mixture at high temperatures.</p>

DOI： 10.1541/ieejpes.141.700

Scopus

CiNii Research

Authorship：Lead author   Language：Japanese  

Authorship：Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)  

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1361-6463/ab66d5

Web of Science

Scopus

Authorship：Lead author,　Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Lead author,　Last author,　Corresponding author   Language：English   Publishing type：Research paper (international conference proceedings)   Publisher：Proceedings of the 2019 5th International Conference on Electric Power Equipment - Switching Technology: Frontiers of Switching Technology for a Future Sustainable Power System, ICEPE-ST 2019  

This report describes experimental results on DC interruption for three experiments: (1) silica-sand filling (designation: Silica), (2) polymer cylinder installation without silica-sand filling (designation: P5-Air), and (3) polymer cylinder installation with silica-sand filling (designation: P5-Silica). The shape of polymer cylinder was fixed at an inner diameter of 5 mm and a length of 15 mm. A damping DC with a peak current of 750 A was supplied to an established experimental system. A current and a voltage between electrodes were measured during the current supplying period. As experimental results, the arc resistance between electrodes were measured to be 0.15 for Silica, 0.20 for P5-Air and 0.56 for P5-Silica at a peak current, respectively. This implies that silica-sand confined in the polymer cylinder effectively contributes to the arc voltage rise at around a peak current. During a current decaying periods, the arc resistance for P5-Air was measured to be almost same value for P5-Silica. This also implies that an interaction between the polymer and the arc rises the arc resistance during the current decaying period.

DOI： 10.1109/ICEPE-ST.2019.8928816

Scopus

Publisher：Proceedings of the 2019 5th International Conference on Electric Power Equipment - Switching Technology: Frontiers of Switching Technology for a Future Sustainable Power System, ICEPE-ST 2019  

The following three experiments were conducted as an attempt to raise the DC arc voltage during current interrupting process in silica sand. The purpose of the first experiment is to examine the influence of the interelectrode distance of the graphite electrode on the arc length. The three types of interelectrode distance were set in the arc quenching chamber and supplied a damping DC current. As experimental results, voltage between electrodes was not effectively rose with elongation in interelectrode distance in the silica sand. The purpose of the second experiment is to achieve further rise in the arc voltage. In this experiment, PA66-cylinder was arranged between electrodes. As the experiment result, arrangement of PA66-cylinder effectively increases the arc voltage. This may be because the expansion of the arc diameter was restricted to the interaction between the arc and the inner wall of the cylinder. The purpose of the third experiment is to investigate the influence of arc voltage rise effect on the inner diameter of the cylinder. The main factors causing the arc voltage rise are the effect of limiting the arc diameter by the inner diameter and the effect of ablating of silica sand.

DOI： 10.1109/ICEPE-ST.2019.8928782

Scopus

Authorship：Corresponding author   Language：Japanese   Publishing type：Research paper (conference, symposium, etc.)  

Authorship：Lead author   Language：English   Publishing type：Research paper (international conference proceedings)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：{IOP} Publishing  

DOI： 10.1088/1361-6463/ab1c9f

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Japan Society of Applied Physics  

The spatial distribution of the Ti vapor admixture ratio (X Ti) was determined together with Ti excitation temperature () from two-dimensional (2D) optical emission spectroscopy (OES) during Ti feedstock injection into an Ar induction thermal plasma (ICTP) torch for Ti nanoparticle synthesis. The X Ti is one important parameter affecting ICTP properties such as its electrical conductivity. The value of X Ti was estimated from the radiation intensity ratio of the Ar atomic line to the Ti atomic line, and obtained from 2D OES observation. Furthermore the electron density (n e) was also determined from the estimated results of and X Ti through the equilibrium composition. These 2D OES results revealed as 2500-4000 K at around the central axis of the ICTP torch, although it was higher than 4000 K in the off-axis region. In the off-axis region, X Ti and n e were much higher than in the on-axis region.

DOI： 10.7567/JJAP.57.036101

Scopus

Language：English   Publishing type：Research paper (scientific journal)   Publisher：IOP PUBLISHING LTD  

Using 20kW Ar-H-2 pulse-modulated induction thermal plasma (PMITP) with time-controlled feeding of feedstock (TCFF), numerous Si nanowires were synthesized rapidly at 1,000mgh(-1) without the intentional addition of catalysts. The PMITP + TCFF method is our original method for nanomaterial synthesis. The PMITP periodically provides a unique field including higher-temperature plasma during "on-time" and a lower-temperature plasma during "off-time". For rapid and efficient evaporation, metal-grade Si powder feedstock was intermittently injected synchronously into the generated Ar-H-2 PMITP. The synthesized products were analyzed using various analytical techniques. The synthesized products were Si nanowires 10-30 nm in diameter with a SiOx surface layer. (C) 2017 The Japan Society of Applied Physics

DOI： 10.7567/APEX.10.096201

Web of Science

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1361-6595/aa73ca

Web of Science

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： doi:10.1088/0022-3727/49/30/305501

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： doi:10.1088/0022-3727/47/19/195304

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

DOI： doi:10.1088/1742-6596/550/1/012026

Open Access

Language：Japanese  

CiNii Research

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6-029

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Venue：仙台   Country：Japan  

6-252

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6-251

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Venue：仙台   Country：Japan  

6-048

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Venue：仙台   Country：Japan  

6-046

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Venue：仙台   Country：Japan  

6-045

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1a-2

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Venue：長崎   Country：Japan  

EI-26-024/EPP-26-024/HV-26-024

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Country：Taiwan, Province of China  

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Venue：福岡   Country：Japan  

EPP-25-119/SP-25-036/HV-25-117

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Venue：福岡   Country：Japan  

EPP-25-121/SP-25-038/HV-25-119

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Venue：福岡   Country：Japan  

EPP-25-120/SP-25-037/HV-25-118

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Venue：Sendai   Country：Japan  

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Venue：大分   Country：Japan  

Event date： 2025.9

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Venue：長野   Country：Japan  

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Venue：長野   Country：Japan  

Event date： 2025.9

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Venue：長野   Country：Japan  

Event date： 2025.9

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Venue：長野   Country：Japan  

Event date： 2025.9

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Venue：長野   Country：Japan  

Event date： 2025.9

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Venue：長野   Country：Japan  

Event date： 2025.9

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Venue：長野   Country：Japan  

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Venue：沖縄   Country：Japan  

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Venue：福井   Country：Japan  

Event date： 2025.8

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Venue：名古屋   Country：Japan  

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Venue：名古屋   Country：Japan  

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Venue：名古屋   Country：Japan  

Event date： 2025.3

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Venue：東京   Country：Japan  

6-008

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Venue：東京   Country：Japan  

6-192

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Venue：東京   Country：Japan  

6-191

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Venue：東京   Country：Japan  

6-045

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Venue：東京   Country：Japan  

6-039

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Venue：東京   Country：Japan  

6-038

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Venue：東京   Country：Japan  

6-037

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Venue：東京   Country：Japan  

6-036

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Venue：東京   Country：Japan  

6-035

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Venue：東京   Country：Japan  

6-033

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Venue：東京   Country：Japan  

6-032

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Venue：東京   Country：Japan  

6-029

Event date： 2025.3

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Country：Thailand  

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Event date： 2025.2

Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：名古屋   Country：Japan  

Event date： 2024.11

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Country：Japan  

Event date： 2024.11

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Country：Japan  

Event date： 2024.11

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2024.11

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Venue：鹿児島   Country：Japan  

EPP-24-078/SP-24-019/HV-24-080

Event date： 2024.11

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Country：Malaysia  

Event date： 2024.11

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Venue：Chicago   Country：United States  

DOI： 10.1109/IECON55916.2024.10905360

Event date： 2024.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Pattaya   Country：Thailand  

Event date： 2024.9

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Venue：仙台   Country：Japan  

PE-24-171/PSE-24-171

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪   Country：Japan  

125

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪   Country：Japan  

238

Event date： 2024.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪   Country：Japan  

237

Event date： 2024.8

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Venue：岐阜   Country：Japan  

Event date： 2024.8

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Venue：岐阜  

Event date： 2024.8

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Venue：岐阜   Country：Japan  

Event date： 2024.8

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Venue：岐阜   Country：Japan  

Event date： 2024.8

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Venue：岐阜   Country：Japan  

Event date： 2024.8

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Venue：岐阜   Country：Japan  

Event date： 2024.8

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Venue：ひたちなか市   Country：Japan  

Event date： 2024.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：ひたちなか市   Country：Japan  

Event date： 2024.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：ひたちなか市   Country：Japan  

Event date： 2024.8

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Venue：ひたちなか市   Country：Japan  

Event date： 2024.8

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Venue：ひたちなか市   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：徳島   Country：Japan  

Event date： 2024.3

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Venue：Nagoya   Country：Japan  

Event date： 2023.11

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Venue：姫路   Country：Japan  

Event date： 2023.11

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Venue：姫路   Country：Japan  

Event date： 2023.11

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Venue：姫路   Country：Japan  

Event date： 2023.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：放電・プラズマ・パルスパワー/開閉保護/高電圧 合同研究会   Country：Japan  

Event date： 2023.11

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Venue：姫路   Country：Japan  

Event date： 2023.9

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Venue：Greifswald   Country：Germany  

Event date： 2023.9

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Venue：名古屋   Country：Japan  

Event date： 2023.9

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Venue：名古屋   Country：Japan  

Event date： 2023.8

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Venue：豊橋   Country：Japan  

Event date： 2023.8

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Venue：豊橋   Country：Japan  

Event date： 2023.8

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Venue：豊橋   Country：Japan  

Event date： 2023.8

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Venue：豊橋   Country：Japan  

Event date： 2023.8

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Venue：豊橋   Country：Japan  

Event date： 2023.8

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Venue：豊橋   Country：Japan  

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Venue：金沢   Country：Japan  

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Venue：金沢   Country：Japan  

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Venue：Kyoto   Country：Japan  

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Venue：オンライン   Country：Japan  

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Venue：東京   Country：Japan  

Event date： 2023.3

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Venue：名古屋   Country：Japan  

Event date： 2023.3

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Venue：名古屋   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋   Country：Japan  

Event date： 2023.3

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Venue：名古屋   Country：Japan  

Event date： 2023.3

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Venue：名古屋   Country：Japan  

Event date： 2023.3

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Venue：名古屋   Country：Japan  

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Venue：名古屋   Country：Japan  

Event date： 2023.3

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Venue：名古屋   Country：Japan  

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Venue：名古屋   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋   Country：Japan  

Event date： 2022.11

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Venue：Medan   Country：Indonesia  

Event date： 2022.11

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Venue：Okinawa, Japan   Country：Japan  

Event date： 2022.11

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Venue：Okinawa, Japan   Country：Japan  

Event date： 2022.11

Language：English   Presentation type：Oral presentation (general)  

Venue：Okinawa, Japan   Country：Japan  

Event date： 2022.11

Language：English   Presentation type：Oral presentation (general)  

Venue：Okinawa, Japan   Country：Japan  

Event date： 2022.11

Language：English   Presentation type：Oral presentation (general)  

Venue：Okinawa, Japan   Country：Japan  

Event date： 2022.10

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福井大学文京キャンパス   Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：オンライン   Country：Japan  

Event date： 2022.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.8

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Venue：オンライン   Country：Japan  

Event date： 2022.8

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Venue：Fukuoka/Hybrid   Country：Japan  

Event date： 2022.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学   Country：Japan  

Event date： 2022.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学   Country：Japan  

Event date： 2022.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学   Country：Japan  

Event date： 2022.6 - 2022.7

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Venue：Korea/Hybrid   Country：Korea, Republic of  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2022.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Korea/Hybrid   Country：Korea, Republic of  

Event date： 2022.3

Language：English   Presentation type：Oral presentation (general)  

Country：Korea, Republic of  

Event date： 2022.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Korea/Hybrid   Country：Korea, Republic of  

Event date： 2021.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.11

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.7

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン   Country：Japan  

Event date： 2021.6

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：オンライン   Country：Japan  

Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2021.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.11

Language：English   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：オンライン  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京電機大学  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京電機大学  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京電機大学  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2020.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東京電機大学  

Event date： 2019.12

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2019.12

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2019.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2019.10

Language：English   Presentation type：Oral presentation (general)  

DOI： 10.1109/ICEPE-ST.2019.8928816

Scopus

Event date： 2019.10

Language：English   Presentation type：Oral presentation (general)  

DOI： 10.1109/ICEPE-ST.2019.8928782

Scopus

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2019.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2019.7

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2019.7

Language：English   Presentation type：Oral presentation (general)  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2019.3

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2018.11

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2018.11

Language：English   Presentation type：Poster presentation  

Venue：Kanazawa   Country：Japan  

Event date： 2018.9

Language：Japanese   Presentation type：Oral presentation (general)  

Event date： 2018.7

Language：English   Presentation type：Oral presentation (general)  

Venue：Toulouse   Country：France  

Event date： 2018.7

Language：English   Presentation type：Poster presentation  

Venue：Toulouse   Country：France  

Event date： 2018.3

Language：English   Presentation type：Poster presentation  

Venue：Nagoya   Country：Japan  

Event date： 2017.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Chung Yuan Christian University   Country：China  

Event date： 2017.12

Language：English   Presentation type：Oral presentation (invited, special)  

Country：Japan  

Event date： 2017.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Taoyuan   Country：Taiwan, Province of China  

Event date： 2017.9

Language：Japanese   Presentation type：Oral presentation (invited, special)  

Venue：福岡国際会議場   Country：Japan  

Event date： 2017.7 - 2017.8

Language：English   Presentation type：Oral presentation (general)  

Venue：Montreal, Canada   Country：Canada  

Event date： 2017.7

Language：English   Presentation type：Oral presentation (general)  

Venue：Montreal   Country：Canada  

Event date： 2016.12

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Brisbane   Country：Australia  

Event date： 2016.7

Language：English   Presentation type：Oral presentation (general)  

Venue：Munich   Country：Germany  

Event date： 2016.6 - 2016.7

Language：English   Presentation type：Oral presentation (general)  

Venue：Kaohsiung convention center   Country：China  

Event date： 2016.5

Language：English   Presentation type：Oral presentation (general)  

Venue：Shanghai   Country：China  

Event date： 2016.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagoya   Country：Japan  

Event date： 2015.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagasaki   Country：Japan  

Event date： 2015.12

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagasaki   Country：Japan  

Event date： 2015.10

Language：English   Presentation type：Oral presentation (general)  

Venue：Hawaii, USA   Country：United States  

Event date： 2015.10

Language：English   Presentation type：Oral presentation (general)  

Venue：Honolulu   Country：United States  

Event date： 2015.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：東広島市   Country：Japan  

Event date： 2015.7

Language：English   Presentation type：Poster presentation  

Venue：Antwerp   Country：Belgium  

Event date： 2015.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Nagoya   Country：Japan  

Event date： 2015.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：平塚市   Country：Japan  

Event date： 2014.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Adelaide   Country：Australia  

Event date： 2014.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：札幌市   Country：Japan  

Event date： 2014.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：大阪市   Country：Japan  

Event date： 2014.7

Language：English   Presentation type：Poster presentation  

Venue：Toulouse   Country：France  

Event date： 2014.6

Language：English   Presentation type：Oral presentation (invited, special)  

Venue：Toulouse   Country：France  

Event date： 2014.3

Language：English   Presentation type：Poster presentation  

Venue：Nagoya   Country：Japan  

Event date： 2014.3

Language：English   Presentation type：Oral presentation (general)  

Venue：Morroco   Country：Morocco  

Event date： 2014.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：相模原市   Country：Japan  

Event date： 2014.2

Language：English   Presentation type：Oral presentation (general)  

Venue：Fukuoka   Country：Japan  

Event date： 2013.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Fukuoka   Country：Japan  

Event date： 2013.9

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：京都市   Country：Japan  

Event date： 2013.8

Language：English   Presentation type：Oral presentation (general)  

Venue：Cairns   Country：Australia  

Event date： 2013.8

Language：English   Presentation type：Poster presentation  

Venue：Cairns   Country：Australia  

Event date： 2013.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：名古屋大学   Country：Japan  

Event date： 2013.2

Language：English   Presentation type：Poster presentation  

Venue：Gero   Country：Japan  

Event date： 2012.10

Language：English   Presentation type：Oral presentation (general)  

Venue：Kyoto   Country：Japan  

Event date： 2012.8

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：富山県立大学   Country：Japan