Updated on 2024/09/19
工学博士 （ 1991.1 名古屋大学 ）
Others / Others / Electric Power Engineering and Electrical Machinery
Development of Superconducting Power Apparatus and Systems
Charging and Discharge Phenomena in High Voltage Power Apparatus
Development of Environmentally Benign Energy Apparatus and Systems
Nagoya University Graduate School, Division of Engineering
- 1990
Country： Japan
Nagoya University Faculty of Engineering
- 1985
Country： Japan
電気学会
IEEE
CIGRE
低温工学協会
放電学会
電気学会 電気学術振興賞論文賞
2023.5 電気学会
CIGREパリ大会日本論文優秀賞
2022.7 日本CIGRE国内委員会
電気学会 優秀技術活動賞（技術報告賞）
2022.6 電気学会
電気学会 電気学術振興賞論文賞
2018.5 電気学会
電気学会 優秀技術活動賞（技術報告賞）
2014.5 電気学会
電気学会 電気学術振興賞論文賞
2013.5 電気学会
電気学会 電気学術振興賞論文賞
2013.5 電気学会
低温工学協会 大島賞優良発表賞
2008.5 低温工学協会
電気学会 電気学術振興賞論文賞
2005.5 電気学会
電気学会 電気学術振興賞進歩賞
2003.5 電気学会
低温工学協会 大島賞優良発表賞
2000.5 低温工学協会
電気学会 電気学術振興賞論文賞
1996.5 電気学会
Improvement of AC Conditioning Effect in Vacuum by High Frequency Voltage Reviewed
R.Konagi, H.Kojima, S.Iitsuka, M.Kobayashi, N.Hayakawa
IEEJ Transactions on Electrical and Electronic Engineering 2024
コンデンサ形計器用変圧器の期待寿命評価方法および部分放電進展特性 Reviewed
永木雄也，林恭平，小島寛樹，吉田昌展，大谷彰，早川直樹
電気学会論文誌B 2023
Breakdown Charge Dependence of Counter Electrode Material Adhesion and Dielectric Strength after Spark Conditioning in Vacuum Reviewed
N.Kita, H.Kojima, N.Hayakawa, H.Fukuda, K.Yamamura
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION 2023
Volume Effect of Dynamic Breakdown Strength in Liquid Nitrogen under Transient Bubble Disturbance for Resistive Superconducting Fault Current Limiters Reviewed
N.Hayakawa, Y.Mori, H.Kojima
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 29 ( 1 ) page： 264 - 269 2022
Development of Sophisticated Cone-Type Insulating Spacer for 245 kV Class GIS by Functional Insulating Materials Reviewed
K.Okamoto, N.Hayakawa, M.Hikita, H.Okubo, K.Kato, N.Osawa
CIGRE Paris Session Vol. 10648 2022
Electric Field Grading and Discharge Inception Voltage Improvement on HVDC GIS/GIL Spacer with Permittivity and Conductivity Graded Materials (ε/σ-FGM) Reviewed
Rachmawati, H.Kojima, K.Kato, N.Zebouchi, N.Hayakawa
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 29 ( 5 ) page： 1811 - 1817 2022
Melting and Generation of Micro-protrusions on Cathode Surface during Spark Conditioning Process in Vacuum Reviewed
N.Kita, F.Kondo, H.Kojima, N.Hayakawa, H.Fukuda, K.Yamamura
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 29 ( 3 ) page： 1160 - 1166 2022
Breakdown Characteristics of Cone-type ε-FGM Spacer for Gas Insulated Switchgears Reviewed
Y.Miyazaki, H.Kojima, H.Masui, H.Mitsudome, H.Yanase, K.Okamoto, K.Watanabe, K.Kato, N.Hayakawa
Vol. 141 ( 10 ) 2021.10
Development of Insulation System to Prevent Local Carbonization inside Stator Core of a Product Inverter-fed Motor Reviewed
Vol. 141 ( 4 ) page： 260-268 2021.4
DC Electric Field Distribution under Gas-Conductivity-Dominant Condition in Gas-Solid Composite Insulation Systems Reviewed
Vol. 141 ( 2 ) page： 156-163 2021.2
Dielectric characteristics of liquid nitrogen / synthetic paper composite insulation system for extra high voltage HTS cable Reviewed
N.Hayakawa, K.Yamakami, T.Masuda, H.Kojima
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY Vol. 31 ( 5 ) 2021
Time and Space Transition of DC Electric Field Distribution Based on Emerging Field by Accumulated Charge in Gas-solid Composite Insulation Structure Reviewed
R.Nakane, N.Hayakawa, H.Okubo
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION 2021
Time Transition of Activated Conductivity Distribution in Air and Charge Accumulation in Air-solid Composite Insulation Systems under DC Partial Discharge Reviewed
R.Nakane, H.Kojima, N.Hayakawa
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION 2021
Electric Field Simulation of Permittivity and Conductivity Graded Materials (e/s-FGM) for HVDC GIS Spacers Reviewed International coauthorship
Rachmawati, H.Kojima, N.Hayakawa, K.Kato, N.Zebouchi
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION 2021
Alternative Test Method of Internal Arcing for Replacing SF6 by Air in SF6 Insulated Power Equipment Reviewed
M.Kotari, M.Iwata, H.Kojima, N.Hayakawa
Engineering Research Express Vol. 3 ( 035005 ) 2021
Partial Discharge Inception Voltage under Inverter Surge Voltage Considering Interactive Effects of Environmental Factors Reviewed
Vol. 140 ( 7 ) page： 349-356 2020.7
絶縁油-プレスボード複合絶縁構成における直流電界ストレスの時間・空間推移特性 Reviewed
中根龍一，加藤克巳， 早川直樹，大久保仁
電気学会論文誌A Vol. 140 ( 2 ) page： 56-63 2020.2
インバータ駆動機におけるカーボン遊離現象の基礎検討 Reviewed
吉武勇一郎，小島啓明， 笠井友樹，丸山正一， 小島寛樹，早川直樹
電気学会論文誌A Vol. 140 ( 1 ) page： 40-47 2020.1
Quench-induced Dynamic Breakdown Characteristics of HTS Pancake Coil Model in Liquid Nitrogen for Resistive SFCL Invited Reviewed
N.Hayakawa, M.Mimbu, Y.Mori, H.Kojima, S.Isojima, M.Kuwata
Journal of Physics: Conference Series (JPCS) Vol. 1559 page： 12100 2020
Fault Current Limitation Coordination of Multiple SFCLs in IEEE 14-Bus Test System Reviewed
N.Hayakawa, Y.Mori, H.Kojima
Journal of Physics: Conference Series (JPCS) Vol. 1559 page： 12138 2020
Resin injection behavior in process of manufacturing insulation spacer with permittivity gradient using computational fluid dynamics
Imai Takahiro, Hoshina Yoshikazu, Kojima Hiroki, Hayakawa Naoki
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 26 ( 5 ) page： 1669-1677 2019.10
Comparison of permittivity gradient in resin injected and simulated cone-shaped spacers
Imai Takahiro, Takeuchi Miwa, Hoshina Yoshikazu, Kojima Hiroki, Hayakawa Naoki
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 26 ( 5 ) page： 1678-1685 2019.10
Dynamic Breakdown Characteristics of a Pancake Coil Model for Resistive-Type Superconducting Fault Current Limiters
Hayakawa Naoki, Mimbu Masataka, Kojimao Hiroki, Isojima Shigeki, Kuwata Minoru
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY Vol. 29 ( 5 ) 2019.8
インバータサージ電圧下における巻線の部分放電開始電圧に及ぼす温度および湿度の複合的影響 Reviewed
梶武文，浅井洋光，小島寛樹，早川直樹
電気学会論文誌A Vol. 139 ( 1 ) page： 30-37 2019.1
Simulation on Discharge Inception Voltage Improvement of GIS Spacer with Permittivity Graded Materials (epsilon-FGM) Using Flexible Mixture Casting Method
Hayakawa Naoki, Miyaji Yoshitaka, Kojima Hiroki, Kato Katsumi
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 25 ( 4 ) page： 1318-1323 2018.8
Fault Current Limitation Coordination in Electric Power Grid With Superconducting Fault Current Limiters
Hayakawa Naoki, Maeno Yuya, Kojima Hiroki
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY Vol. 28 ( 4 ) 2018.6
Volume Effect of Dynamic Breakdown Strength in LN2 for Insulation Design of Resistive Superconducting Fault Current Limiters
Hayakawa Naoki, Ishida Kazuki, Mimbu Masataka, Kojima Hiroki, Isojima Shigeki, Kuwata Minoru
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY Vol. 28 ( 4 ) 2018.6
誘電率傾斜機能材料(ε-FGM)を用いたGISスペーサモデルの作製とSF6ガス中絶縁破壊電圧の理論的推定 Reviewed
宮路仁崇，小島寛樹， 加藤克巳，早川直樹
電気学会論文誌A Vol. 138 ( 4 ) page： 155-162 2018
Discharge Pattern Discrimination in Vacuum Interrupter with Non-contact Measurement of Shield Potential
Kong Fei, Kojima Hiroki, Hayakawa Naoki, Kimura Toshinori, Tsukima Mitsuru
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 24 ( 5 ) page： 3265-3269 2017.10
Optimum Breakdown Charge for Maximum Dielectric Strength in Spark Conditioning in Vacuum under a Non-uniform Electric Field
Kojima H., Takahashi T., Hayakawa N., Hasegawa K., Sakaki M.
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 24 ( 4 ) page： 2660-2665 2017.8
Electrical Insulation Characteristics and Mechanisms of Low Dielectric Loss Materials for High-Voltage HTS Cables
Hayakawa Naoki, Ishida Kazuki, Matsuoka Tatsuya, Kojima Hiroki
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY Vol. 27 ( 4 ) 2017.6
Breakdown Characteristics and Mechanisms of Liquid Nitrogen Under Transient Thermal Stress for Superconducting Fault Current Limiters
Hayakawa Naoki, Matsuoka Tatsuya, Kojima Hiroki, Isojima Shigeki, Kuwata Minoru
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY Vol. 27 ( 4 ) 2017.6
Calculation Model for Predicting Partial-discharge Inception Voltage in a Non-uniform Air Gap while Considering the Effect of Humidity
Rokunohe Toshiaki, Kato Tatsuro, Kojima Hiroki, Hayakawa Naoki, Okubo Hitoshi
IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION Vol. 24 ( 2 ) page： 1123-1130 2017.4
ナノ粒子添加絶縁油の交流電気絶縁破壊電圧の向上メカニズム Reviewed
小島寛樹，近藤貴文，花井正広，早川直樹
電気学会論文誌A Vol. 137 ( 2 ) page： 101-106 2017
平角線モータにおける部分放電開始電圧のばらつき低減方法 Reviewed
脇本亨，小島寛樹，早川直樹
電気学会論文誌A Vol. 136 ( 3 ) page： 121-127 2016
真空中沿面フラッシオーバ進展過程における絶縁物上過渡帯電存在時の実効的２次電子放出係数 Reviewed
中野裕介，小島寛樹，土屋賢治，早川直樹
電気学会論文誌A Vol. 136 ( 3 ) page： 128-134 2016
Pressure Dependence and Size Effect of LN2 Breakdown Characteristics under Transient Thermal Stress Reviewed
N.Hayakawa, T.Matsuoka, K.Ishida, H.Kojima, S.Isojima, M.Kuwata
IEEE Trans. on Applied Superconductivity Vol. 26 ( 3 ) page： 7700604 2016
Discharge Characteristics of Composite Insulation System with Floating Electrode and Solid Insulator in Vacuum Reviewed
F.Kong, Y.Nakano, H.Kojima, N.Hayakawa, T.Kimura, M.Tsukima
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 23 ( 2 ) page： 1219-1225 2016
Discharge Characteristics for Various Discharge Patterns under Negative Lightning Impulse Voltage in Vacuum Reviewed
F.Kong, Y.Nakano, H.Kojima, N.Hayakawa, T.Kimura, M.Tsukima
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 23 ( 2 ) page： 813-818 2016
Fabrication and Simulation of Permittivity Graded Materials for Electric Field Grading of Gas Insulated Power Apparatus Reviewed
N.Hayakawa, J.Ishiguro, H.Kojima, K.Kato, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 23 ( 1 ) page： 547-554 2016
Classification of Impulse Breakdown Mechanisms under Non-uniform Electric Field in Air Reviewed
H.Kojima, K.Hotta, T.Kitamura, N.Hayakawa, A.Otake, K.Kobayashi, T.Kato, T.Rokunohe H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 23 ( 1 ) page： 194-201 2016
Analysis of Conditioning and Damaging Process in Vacuum Based on Breakdown Probability Distribution Reviewed
H.Kojima, Y.Otake, T.Takahashi, N.Hayakawa, K.Hasegawa, H.Saito, M.Sakaki
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 23 ( 1 ) page： 43-48 2016
Control and Suppression of Impulse Surface Flashover in Vacuum Based on Discharge Development Mechanisms Reviewed
Y.Nakano, H.Kojima, K.Tsuchiya, N.Hayakawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 23 ( 1 ) page： 35-42 2016
Dependence of Spark Conditioning on Breakdown Charge and Electrode Material under a Non-Uniform Electric Field Reviewed
H.Kojima, T.Takahashi, N.Hayakawa, K.Hasegawa, H.Saito, M.Sakaki
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 23 ( 5 ) page： 3224-3230 2016
真空中の複合絶縁系における放電パターンの識別 Reviewed
孔飛，小島寛樹，木村俊則，月間満，早川直樹
電気学会論文誌A Vol. 136 ( 9 ) page： 594-602 2016
Measurement and Evaluation of Partial Discharge Inception Voltage for Enameled Rectangular Wires under AC Voltage Reviewed
T.Wakimoto, H.Kojima, N.Hayakawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 23 ( 6 ) page： 3566-3574 2016
Power Flow Control and Maintenance Strategy of Transformers in Transmission and Distribution Systems Reviewed
H.Kojima, K.Fukaya, N.Hayakawa, M.Hanai, H.Okubo
Vol. 135 ( 5 ) page： 316-321 2015
Quench-Induced Dynamic Breakdown Characteristics of LN2 and LN2/PPLP Composite Electrical Insulation System for Superconducting Power Apparatus Reviewed
N.Hayakawa, T.Matsuoka, S.Nishimachi, H.Kojima
IEEE Trans. on Applied Superconductivity Vol. 25 ( 3 ) page： 7700304 2015
Experimental Results of 275 kV-3 kA REBCO HTS Power Cable Reviewed
M.Yagi, J.Liu, S.Mukoyama, T.Mitsuhashi, J.Teng, N.Hayakawa, X.Wang, A.Ishiyama,
IEEE Trans. on Applied Superconductivity Vol. 25 ( 3 ) page： 5401405 2015
Fault Current Limitation Coordination in Power Transmission System with Superconducting Fault Current Limiting Cables (SFCLC) Reviewed
H.Kojima, T.Osawa, N.Hayakawa
IEEE Trans. on Applied Superconductivity Vol. 25 ( 3 ) page： 5401904 2015
Impulse Surface Flashover Development Associated with Transient Charging by Explosive Electron Emission in Vacuum Reviewed
Y.Nakano, H.Kojima, K.Tsuchiya, N.Hayakawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 22 ( 4 ) page： 2390-2397 2015
Size Effect on Breakdown Strength in Sub-cooled Liquid Nitrogen for Superconducting Power Apparatus Reviewed
N.Hayakawa, S.Nishimachi, H.Kojima, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 22 ( 5 ) page： 2565-2571 2015
真空中における突発的電子放出に起因する沿面フラッシオーバ進展過程の過渡帯電特性 Reviewed
中野裕介，小島寛樹，土屋賢治，早川直樹
電気学会論文誌A Vol. 134 ( 11 ) page： 578-584 2014
Influence of longitudinal temperature distribution on current limiting function of Superconducting Fault Current Limiting Cable (SFCLC) Reviewed
H.Kojima, T.Osawa, N.Hayakawa , M.Hanai, H.Okubo
Journal of Physics: Conference Series (JPCS) Vol. 507 page： 032026 2014
A Novel Electrical Insulating Material for 275 kV High-Voltage HTS Cable with Low Dielectric Loss Reviewed
N.Hayakawa, S.Nishimachi, O.Maruyama, T.Ohkuma, J.Liu, M.Yagi
Journal of Physics: Conference Series (JPCS) Vol. 507 page： 032021 2014
Pre-discharge and Flashover Characteristics of Impulse Surface Discharge in Vacuum Reviewed
Y.Nakano, H.Kojima, N.Hayakawa, K.Tsuchiya, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 21 ( 1 ) page： 403-410 2014
Technique for Discriminating the Type of PD in SF6 Gas Using the UHF Method and the PD Current with a Metallic Particle Reviewed
M.Hanai, H.Kojima, N.Hayakawa, R.Mizuno, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 21 ( 1 ) page： 88-95 2014
Physical Mechanisms of Partial Discharges at Nitrogen Filled Delamination in Epoxy Cast Resin Power Apparatus Reviewed
D.-E.A.Mansour, H.Kojima, N.Hayakawa, M.Hanai, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 20 ( 2 ) page： 454-461 2013
Status of 275 kV Class REBCO Superconducting Cable Development Reviewed
S.Mukoyama, M.Yagi, T.Mitsuhashi, T.Nomura, J.Ten, R.Nakayama, T.Ohkuma, O.Maruyama, Y.Aoki, T.Saitoh, N.Amemiya, A.Ishiyama, N.Hayakawa
IEEE Trans. on Applied Superconductivity Vol. 23 ( 3 ) page： 5402804 2013
Feasibility Study on Superconducting Power Flow Controller and Fault Current Limiter (SPFCL) Reviewed
N.Hayakawa, X.Mao, H.Kojima, M.Hanai, H.Okubo, N.Kashima, S.Nagaya, S.Sugimoto
IEEE Trans. on Applied Superconductivity Vol. 23 ( 3 ) page： 5600504 2013
Development of 66 kV and 275 kV Class REBCO HTS Power Cables Reviewed
O.Maruyama, T.Ohkuma, T.Masuda, Y.Ashibe, S.Mukoyama, M.Yagi, T.Saitoh, T.Hasegawa, N.Amemiya, A.Ishiyama, N.Hayakawa
IEEE Trans. on Applied Superconductivity Vol. 23 ( 3 ) page： 5401405 2013
部分放電メカニズムに基づくGIS中金属異物形状同定手法 Reviewed
小島寛樹，鈴木隆文，早川直樹，花井正広，大久保仁
電気学会論文誌B Vol. 133 ( 1 ) page： 114-120 2013
Integration of Asset Management and Smart Grid with Intelligent Grid Management System Reviewed
M.Hanai, H.Kojima, N.Hayakawa, K.Shinoda, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 20 ( 6 ) page： 2195-2202 2013
Charge behavior in Palm Fatty Acid Ester Oil (PFAE) / pressboard composite insulation system under voltage application Reviewed
H.Kojima. N.Hayakawa, H.Okubo, K.Kato, K.Kawanishi, H.Koide
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 19 ( 2 ) page： 419-423 2012
Estimation of Partial Discharge Inception Voltage of Magnet Wire under Inverter Surge Voltage by Volume-Time Theory Reviewed
N.Hayakawa, F.Shimizu, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 19 ( 2 ) page： 550-557 2012
Feasibility Study on High Temperature Superconducting Fault Current Limiting Cable (SFCLC) Using Flux Flow Resistance Reviewed
H.Kojima, F.Kato, M.Hanai, N.Hayakawa, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 22 ( 2 ) page： 4800105 2012
Current limitation and recovery function for superconducting fault current limiting transformer (SFCLT) Reviewed
J.Himbele, H.Kojima, N.Hayakawa, M.Hanai, H.Okubo
Physics Procedeia Vol. 36 page： 841-844 2012
Superconducting Fault Current Limiting Cable (SFCLC) with Current Limiting and Recovery Function Reviewed
H.Kojima, F.Kato, N.Hayakawa, M.Hanai, H.Okubo
Physics Procedeia Vol. 36 page： 1296-1300 2012
Recent Progress in Electrical Insulation Techniques for HTS Power Apparatus Reviewed
N.Hayakawa, H.Kojima, M.Hanai, H.Okubo
Physics Procedeia Vol. 36 page： 1305-1308 2012
周波数応答解析によるモータサージ電圧の推定と抑制 Reviewed
脇本亨，高橋芳光，木村統公，鳴海礼斗史，早川直樹
電気学会論文誌A Vol. 132 ( 8 ) page： 630-637 2012
Model Cable Tests for a 275 kV 3 kA HTS Power Cable Reviewed
S.Mukoyama, M.Yagi, T.Yonemura, T.Nomura, N.Fujiwara, Y.Ichikawa, Y.Aoki, T.Saitoh, N.Amemiya, A.Ishiyama, N.Hayakawa
IEEE Trans. on Applied Superconductivity Vol. 21 ( 3 ) page： 976-979 2011
Analysis of Current Limiting and Recovery Characteristics of Superconducting Fault Current Limiting Transformer (SFCLT) with YBCO Coated Conductors Reviewed
N.Hayakawa, T.Kito, H.Kojima, M.Hanai, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 21 ( 3 ) page： 1422-1425 2011
Current Limiting and Recovery Characteristics of 2 MVA Class Superconducting Fault Current Limiting Transformer (SFCLT) Reviewed
H.Kojima, M.Kotari, T.Kito, N.Hayakawa, M.Hanai, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 21 ( 3 ) page： 1401-1404 2011
Development Process of Impulse Surface Flashover on Alumina Dielectrics in Vacuum Reviewed
H.Kojima, N.Hayakawa, T.Ishida, H.Okubo, K.Tsuchiya
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 18 ( 3 ) page： 918-923 2011
Evaluation of UHF Method for Partial Discharge Measurement by Simultaneous Observation of UHF Signal and Current Pulse Waveforms Reviewed
M.Yoshida, H.Kojima, N.Hayakawa, F.Endo, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 18 ( 2 ) page： 425-431 2011
Progress in Development of Superconducting Fault Current Limiting Transformer (SFCLT) Reviewed
N.Hayakawa, H.Kojima, M.Hanai, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 21 ( 3 ) page： 1397-1400 2011
Conditioning Mechanism of Cu-Cr Electrode Based on Electrode Surface State under Impulse Voltage Application in Vacuum Reviewed
H.Kojima, N.Hayakawa, R.Nishimura, H.Okubo, H.Sato, H.Saito, Y.Noda
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 18 ( 6 ) page： 2108-2114 2011
部分放電の時系列測定によるGIS内部の欠陥状態識別 Reviewed
吉田昌展，鈴木啓介，小島寛樹，早川直樹，花井正広，大久保仁
電気学会論文誌B Vol. 131 ( 11 ) page： 905-911 2011
湿度の影響を考慮した気中不平等ギャップにおける部分放電開始計算モデルの開発 Reviewed
柳田憲史，加藤達朗，六戸敏昭，岩田健，小島寛樹，早川直樹，大久保仁
電気学会論文誌A Vol. 131 ( 12 ) page： 1017-1023 2011
Partial Discharge Activities under AC/Impulse Superimposed Voltage in LN2/Polypropylene Laminated Paper Insulation System for HTS Cables Reviewed
N.Hayakawa, R.Yamaguchi, U.Ukai, H.Kojima, F.Endo, H.Okubo
Journal of Physics: Conference Series (JPCS) Vol. 234 ( 032020 ) 2010
Charge Accumulation Effects on Time Transition of Partial Discharge Activity at GIS Spacer Defects Reviewed
D.A.Mansour, K.Nishizawa, H.Kojima, N.Hayakawa, F.Endo, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 17 ( 1 ) page： 247-255 2010
Dielectric Properties of Epoxy/Alumina Nanocomposite Influenced by Agglomerates Control Reviewed
M.Kurimoto, H.Okubo, K.Kato, M.Hanai, Y.Hoshina, M.Takei, N.Hayakawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 17 ( 3 ) page： 1268-1275 2010
Partial Discharge and Associated Mechanisms for Micro Gap Delamination at Epoxy Spacer in GIS Reviewed
D.A.Mansour, K.Nishizawa, H.Kojima, N.Hayakawa, F.Endo, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 17 ( 3 ) page： 861-867 2010
Permittivity Characteristics of Epoxy/Alumina Nanocomposite with High Particle Dispersibility by Combining Ultrasonic Wave and Centrifugal Force Reviewed
M.Kurimoto, H.Okubo, K.Kato, M.Hanai, Y.Hoshina, M.Takei, N.Hayakawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 17 ( 4 ) page： 1268-1275 2010
Development of 2 MVA Class Superconducting Fault Current Limiting Transformer (SFCLT) with YBCO Coated Conductors Reviewed
M.Kotari, H.Kojima, N.Hayakawa, F.Endo, H.Okubo
Journal of Physics: Conference Series (JPCS) Vol. 234 ( 032070 ) page： - 2010
Surface Charge Accumulation and Partial Discharge Activity for Small Gaps of Electrode/Epoxy Interface in SF6 Gas Reviewed
D.A.Mansour, H.Kojima, N.Hayakawa, F.Endo, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 16 ( 4 ) page： 1150-1157 2009
Dynamic Thermal Characteristics of HTS Coil for Conduction-cooled SMES Reviewed
H.Kojima, X.Chen, N.Hayakawa, F.Endo, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 19 ( 3 ) page： 2036-2039 2009
Current Limiting Characteristics of Parallel-Connected YBCO Coated Conductors for High-Tc Superconducting Fault Current Limiting Transformer (HTc-SFCLT) Reviewed
K.Omura, H.Kojima, N.Hayakawa, F.Endo, M.Noe, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 19 ( 3 ) page： 1880-1883 2009
*Time Variation of Partial Discharge Activity Leading to Breakdown of Magnet Wire under Repetitive Surge Voltage Application Reviewed
N.Hayakawa, H.Inano, Y.Nakamura, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 15 ( 6 ) page： 1701-1706 2008
*Partial Discharge Activity in Electrical Insulation for High Temperature Superconducting (HTS) Cables Reviewed
H.Okubo, H.Kojima, F.Endo, K.Sahara, R.Yamaguchi, N.Hayakawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 15 ( 3 ) page： 647-654 2008
*Self-recovery Characteristics of High-Tc Superconducting Fault Current Limiting Transformer (HTc-SFCLT) with 2G Coated Conductors Reviewed
H.Kojima, S.Ito, N.Hayakawa, F.Endo, M.Noe, H.Okubo
Journal of Physics: Conference Series page： 12154 2008
*Quench-induced Partial Discharge Characteristics of HTS Cables Reviewed
N.Hayakawa, S.Ueyama, H.Kojima, F.Endo, Y.Ashibe, T.Masuda, M.Hirose
Journal of Physics: Conference Series page： 12053 2008
Electrical Insulation Characteristics of HTS Cables under Quench-induced Thermal Stress Condition Reviewed
N.Hayakawa, S.Ueyama, H.Kojima, F.Endo, T.Masuda, M.Hirose
IEEE Trans. on Applied Superconductivity Vol. 17 ( 2 ) page： 1660-1663 2007
*Breakdown Characteristics of N2O Gas Mixtures for Quasiuniform Electric Field under Lightning Impulse Voltage Reviewed
H.Kojima, O.Kinoshita, N.Hayakawa, F.Endo, H.Okubo, M.Yoshida, T.Ogawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 14 ( 6 ) page： 1492-1497 2007
Technical Development on Partial Discharge Measurement and Electrical Insulation Techniques for Low Voltage Motors Driven by Voltage Inverters Reviewed
H.Okubo, N.Hayakawa, G.C.Montanari
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 14 ( 6 ) page： 1516-1530 2007
Partial Discharge Inception and Propagation Characteristics of Magnet Wire for Inverter-Fed Motor under Surge Voltage Condition Reviewed
N.Hayakawa, M.Morikawa, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 14 ( 1 ) page： 39-45 2007
Thermal Runaway Characteristics of Bi2212 Coil for Conduction-cooled SMES Reviewed
H.Kojima, N.Hayakawa, S.Noguchi, F.Endo, N.Hirano, S.Nagaya, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 17 ( 2 ) page： 1959-1962 2007
High-Tc Superconducting Fault Current Limiting Transformer (HTc-SFCLT) with 2G Coated Conductors Reviewed
H.Okubo, C.Kurupakorn, S.Ito, H.Kojima, N.Hayakawa, F.Endo, M.Noe
IEEE Trans. on Applied Superconductivity Vol. 17 ( 2 ) page： 1768-1771 2007
Streamer and Leader Discharge Propagation Characteristics Leading to Breakdown in Electronegative Gases Reviewed
N.Hayakawa, K.Hatta, S.Okabe, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 113 ( 4 ) page： 842-849 2006
Impulse and ac Partial Discharge Inception and Breakdown Characteristics of LN2/Polypropylene Laminated Paper Composite Insulation System Reviewed
H.Okubo, H.Kojima, F.Endo, K.Sahara, N.Hayakawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 113 ( 3 ) page： 664-669 2006
Common Insulating Properties in Insulating Materials Reviewed
S.Okabe, N.Hayakawa, H.Murase, H.Hama, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 113 ( 2 ) page： 327-335 2006
Simulation of Electrical and Thermal Behavior of High Temperature Superconducting Fault Current Limiting Transformer (HTc-SFCLT) Reviewed
C.Kurupakorn, H.Kojima, N.Hayakawa, F.Endo, N.Kashima, S.Nagaya, M.Noe, H.Okubo
Journal of Physics: Conference Series Vol. 43 page： 950-953 2006
Electrical and Thermal Characteristics of Bi2212/Ag HTS Coils for Conduction-cooled SMES Reviewed
N.Hayakawa, S.Noguchi, C.Kurupakorn, H.Kojima, F.Endo, N.Hirano, S.Nagaya, H.Okubo
Journal of Physics: Conference Series Vol. 43 page： 813-816 2006
N2O混合ガスの絶縁特性におけるシナジズム効果 Reviewed
早川直樹，木下修，小島寛樹，遠藤奎将，吉田昌展，小川達也，大久保仁
電気学会論文誌B Vol. 126 ( 11 ) page： 1164-1170 2006
Impulse Partial Discharge Characteristics and Their Mechanisms under Non-uniform Electric Field in N2/SF6 Gas Mixtures Reviewed
N.Hayakawa, Y.Yoshitake, N.Koshino, T.Ueda, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 12 ( 5 ) page： 1035-1042 2005
A Novel Technique for Partial Discharge and Breakdown Investigation Based on Current Pulse Waveform Analysis Reviewed
H.Okubo, N.Hayakawa
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 12 ( 4 ) page： 736-744 2005
Temperature Dependence of Critical Current at 4.2K–55K of Conduction-cooled Bi2212/Ag Wires Reviewed
H.Kojima, S.Noguchi, C.Kurupakorn, N.Hayakawa, M.Goto, N.Hirano, S.Nagaya, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 15 ( 2 ) page： 2550-2553 2005
High voltage requirements and test of a 10 MVA superconducting fault current limiter Reviewed
M.Noe, K.-P.Juengst, S.Elschner, J.Bock, F.Breuer, R.Kreutz, M.Kleimaier, K.-H.Weck, N. Hayakawa
IEEE Trans. on Applied Superconductivity Vol. 15 ( 2 ) page： 2082-2085 2005
Recovery Characteristics after Current Limitation of High Temperature Superconducting Fault Current Limiting Transformer (HTc-SFCLT) Reviewed
C.Kurupakorn, H.Kojima, N.Hayakawa, M.Goto, N.Kashima, S.Nagaya, M.Noe, K.-P.Juengst, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 15 ( 2 ) page： 1859-1862 2005
Dielectric Characteristics of HTS Cables Based on Partial Discharge Measurement Reviewed
N.Hayakawa, M.Nagino, H.Kojima, M.Goto, T.Takahashi, K.Yasuda, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 15 ( 2 ) page： 1802-1805 2005
CO2ガスのインパルス比と初期電子発生特性 Reviewed
越野尚人，木下修，早川直樹，五島久司，岡部成光，森井浩，大久保仁
電気学会論文誌B Vol. 125 ( 6 ) page： 568-574 2005
Partial Discharge Inception Characteristics of LN2/PP Laminated Paper Composite Insulation System for High Temperature Superconducting Cable Reviewed
N.Hayakawa, T.Kobayashi, M.Hazeyama, T.Takahashi, K.Yasuda, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 12 ( 1 ) page： 166-174 2005
Partial discharge characteristics of inverter-fed motor coil samples under ac and surge voltage conditions Reviewed
N.Hayakawa, H.Okubo
IEEE Electrical Insulation Magazine Vol. 21 ( 1 ) page： 5-10 2005
Electrical Insulation Characteristics at Cryogenic Temperature for High Temperature Superconducting Cables Reviewed
H.Okubo, N.Hayakawa
KIEE International Transactions on Electrophysics and Applications Vol. 4-C ( 1 ) page： 15-20 2004
高温超電導限流変圧器（HTc-SFCLT）の開発 Reviewed
クルパコン チャチャヴァン，早川直樹，鹿島直二，長屋重夫，大久保仁
電気学会論文誌B Vol. 124 ( 10 ) page： 1193-1199 2004
Development of High Temperature Superconducting Fault Current Limiting Transformer (HTc-SFCLT) with Bi2212 Bulk Coil Reviewed
C.Kurupakorn, N.Hayakawa, H.Okubo, N.Kashima, S.Nagaya, M.Noe, K.-P.Juengst
IEEE Trans. on Applied Superconductivity Vol. 14 ( 2 ) page： 900-903 2004
棒－平板電極における空気および窒素ガス中インパルス部分放電および絶縁破壊特性 Reviewed
斉藤 仁，森田啓一，吉川隆司，早川直樹，大久保仁
電気学会論文誌B Vol. 123 ( 2 ) page： 169-174 2003
Electrical Insulation Performance under Thermal and Electric Combined Stress for Resistive Superconducting Fault Current Limiters Reviewed
N.Hayakawa, M.Noe, K.-P.Juengst, H.Okubo
IEEE Trans. on Applied Superconductivity Vol. 13 ( 2 ) page： 1996-1999 2003
V-t characteristics for Partial Discharge Inception of High Temperature Superconducting Power Transmission Cables Reviewed
M.Hazeyama, N.Hayakawa, K.Matsuo, T.Masuda, H.Okubo
Physica C Vol. 372-376 ( 3 ) page： 1551-1554 2002
V-t Characteristics of Partial Discharge Inception in Liquid Nitrogen/PPLP Composite Insulation System for HTS Superconducting Cable Reviewed
H.Okubo, M.Hazeyama, N.Hayakawa, S.Honjo, T.Masuda
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 9 ( 6 ) page： 945-951 2002
Impulse Partial Discharge and Breakdown Characteristics of Rod-Plane Gaps in N2/SF6 Gas Mixtures Reviewed
H.Saitoh, K.Morita, T.Kikkawa, N.Hayakawa, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 9 ( 4 ) page： 544-550 2002
Partial discharge and breakdown mechanisms in ultra-dilute SF6 and PFC gases mixed with N2 gas Reviewed
H.Okubo, T.Yamada, K.Hatta, N.Hayakawa, S.Yuasa, S.Okabe
Journal of Physics D: Applied Physics Vol. 35 ( 21 ) page： 2760-2765 2002
Investigation of Electric Insulation Diagnosis of Solid Insulators in GIS by Partial Discharge Current Pulse Waveform Analysis (PD-CPWA) Reviewed
H.Okubo, A.Matsushita, S.Watanabe, N.Hayakawa, T.Kumai
IEEE PES T&D Vol. 2 page： 925-930 2002
Development of Superconducting Fault Current Limiting Transformer (SFCLT) with the Functions of Fault Current Suppression and System Stability Improvement Reviewed
H.Okubo, H.Kagawa, N.Hayakawa, N.Kashima, S.Nagaya
IEEE PES T&D Vol. 1 page： 301-306 2002
Experimental Study on Superconducting Fault Current Limiting Transformer (SFCLT) for Fault Current Suppression and System Stability Improvement Reviewed
H.Kagawa, N.Hayakawa, N.Kashima, S.Nagaya, H.Okubo
Physica C Vol. 372-376 ( 3 ) page： 1706-1710 2002
Partial Discharge Inception Characteristics under Butt Gap Condition in Liquid Nitrogen/PPLP Composite Insulation System for High Temperature Superconducting Cable Reviewed
M.Hazeyama, T.Kobayashi, N.Hayakawa, S.Honjo, T.Masuda, H.Okubo
IEEE Trans. on Dielectrics and Electrical Insulation Vol. 9 ( 6 ) page： 939-944 2002
Superconducting Fault Current Limiter
Pascal Tixador et al.（ Role： Joint author）
World Scientific Publishing 2018.12
Tailoring of Nanocomposite Dielectrics: from Fundamentals to Devices and Applications
T.Tanaka, A.S.Vaughan et al.（ Role： Joint author）
Pan Stanford Publishing 2016.10
環境調和型社会のためのエネルギー科学
長﨑正雅，早川直樹，他（ Role： Joint author）
（社）コロナ社 2016.1
ナノテク材料～ポリマーナノコンポジット絶縁材料の世界～
田中祀捷，早川直樹，他（ Role： Joint author）
（社）オーム社 2014.8
電気工学ハンドブック（第7版）
大久保仁，早川直樹，他（ Role： Joint author）
（社）電気学会 2013.9
超伝導現象と高温超伝導体
内藤方夫，早川直樹，他（ Role： Joint author）
エヌ・ティー・エス 2013.3
高分子絶縁材料技術とその実例・評価
大木義路，早川直樹，他（ Role： Joint author）
サイエンス＆テクノロジー 2010.3
電力システム工学
大久保仁，一柳勝宏，水野幸男，早川直樹，後藤泰之，松村年郎，鵜飼裕之，滝川浩史（ Role： Joint author）
オーム社 2008.12
High Temperature Superconductivity 1
（ Role： Joint author）
Springer-Verlag 2004.1
電力システム工学
大久保仁，中村光一，早川直樹，後藤泰之，内藤克彦，榊原建樹，松村年郎，田原徳夫（ Role： Joint author）
オーム社 1998.1
High-Temperature Superconducting (HTS) Transformer Experience and Applications International conference
Naoki Hayakawa
International Council on Large Electric Systems
Cryogenic Electrical Insulation - Common Techniques for Superconducting Power Application International conference
Naoki Hayakawa
International Conference on Applied Superconductivity and Electromagnetic Devices
Development of Superconducting Fault Current Limiting Transformer (SFCLT)
International Workshop on HTS Power Applications
Partial Discharge Measurement and Characteristics in Cryogenic Electrical Insulation for HTS Power Apparatus International conference
Cryogenic Dielectrics Workshop
Superconducting Fault Current Limiting Transformer (SFCLT) Project
International Workshop on HTS Power Applications
Quench-induced Dynamic Breakdown Characteristics of Superconducting Power Apparatus International conference
Workshop for Low Temperature High Voltage Problems in Electric Power Engineering
Partial Discharge Inception Characteristics of LN2/Polypropylene Laminated Paper Composite Insulation System for High Temperature Superconducting Cables International conference
Workshop for Low Temperature High Voltage Problems in Electric Power Engineering
革新的機能性絶縁材料の先導研究
2015.2 - 2016.2
エネルギー・環境新技術先導プログラム
Grant type：Competitive
「高電圧機器関連」領域の長期的研究課題に関する調査研究
2008.10 - 2009.3
イットリウム系超電導コイルの絶縁特性評価に関する研究
2008.4 - 2009.3
国内共同研究
インバータ駆動電動機の部分放電測定技術
2008.4 - 2009.3
企業からの受託研究
環境調和型エネルギー輸送技術としての超電導送電に関する研究
2007.4 - 2008.3
Grant type：Competitive
HV/EV用インバータ駆動モータのサージ絶縁性能に及ぼす環境要因の影響に関する研究
2007.4 - 2008.3
国内共同研究
インバータ駆動電動機の部分放電測定技術
2007.4 - 2008.3
企業からの受託研究
極低温電気絶縁に関する調査研究
2006.9 - 2007.3
企業からの受託研究
極低温電気絶縁に関する調査研究
2005.9 - 2006.3
企業からの受託研究
次世代ガス絶縁機器に適用する絶縁ガスの特性に関する研究
2005.4 - 2006.3
国内共同研究
超電導限流変圧器の導入効果に関する調査研究
2004.4 - 2005.3
企業からの受託研究
環境低負荷型ガスの基礎特性解明および次世代ガス絶縁機器適用に関する研究
2004.4 - 2005.3
国内共同研究
Innovative electric field control by functionally graded materials of conductivity in dc gas insulated electric apparatus
Grant number：18H01423 2018.4 - 2021.3
Authorship：Coinvestigator(s)
超伝導限流器の実用化に向けた高信頼度化と合理的設計・運用に関する研究
2017.4 - 2020.3
科学研究費補助金 基盤研究(B)
早川 直樹
Authorship：Principal investigator
Reliable and Rational Design and Operation of Superconducting Fault Current Limiters for Practical Use
Grant number：17H03215 2017.4 - 2020.3
Hayakawa Naoki
Authorship：Principal investigator
Grant amount：\18330000 （ Direct Cost: \14100000 、 Indirect Cost：\4230000 ）
This research investigates the application techniques of superconductivity with zero resistance toward a future electric power transmission system with low cost and low possibility of blackout. In particular, superconducting fault current limiters (SFCL) are expected to be developed and actually introduced in order to protect the system from blackout due to lightning and so on. Then, electrical characteristics of liquid nitrogen to maintain SFCL in superconducting state have been elucidated, and the highly reliable and rational design method of SFCL has been proposed. In addition, the effective introduction and operation methods of SFCL in the system have been proposed.
高温超伝導ケーブルの合理的絶縁設計・試験技術に関する研究
2009 - 2012.3
科学研究費補助金 基盤研究(B)，課題番号：21360128
早川 直樹
Authorship：Principal investigator
高温超伝導ケーブルの動的複合ストレス環境を考慮した高信頼度化に関する研究
2006.4 - 2008.3
科学研究費補助金 基盤研究（Ｂ），課題番号：18360135
早川 直樹
Authorship：Principal investigator
伝導冷却高温超伝導線材のクエンチ／熱暴走検出・保護技術に関する研究
2004.4 - 2006.3
科学研究費補助金 基盤研究（Ｂ），課題番号：16360138
早川 直樹
Authorship：Principal investigator
高温超伝導バルク導体を用いた超伝導限流変圧器の開発に関する研究
2002.4 - 2004.3
科学研究費補助金 基盤研究（Ａ），課題番号：14205040
早川 直樹
Authorship：Principal investigator
高電圧工学
2016
電磁理論
2016
電気エネルギー伝送工学
2016
Electric Power and Energy
2015
First Year Seminar A
2015
超伝導応用工学特論
2015
高電圧工学
2015
電磁理論
2015
電気エネルギー伝送工学
2015
高電圧工学
2014
電磁理論
2014
電気エネルギー伝送工学
2014
電磁理論
2013
First Year Seminar A
2013
超伝導応用工学特論
2013
電気エネルギー伝送工学
2013
線形回路論
2013
線形回路論
2012
電気エネルギー伝送工学
2012
電磁理論
2012
First Year Seminar A
2011
超伝導応用工学特論
2011
線形回路論
2011
電気エネルギー伝送工学
2011
電磁理論
2011
電気エネルギー伝送工学
2010
電磁理論
2010
電気エネルギー変換工学
2009
基礎セミナーＡ
2009
電磁理論
2009
送配電工学
1998.4 - 1999.3 （豊田工業高等専門学校）
送配電工学
1997.4 - 1998.3 （豊田工業高等専門学校）
