Development of Electric Impact Driver Integrated with Inductively Coupled Wireless Power Transfer
K. Uchida; R. Shinozuka; T. Tanaka
IEEJ Journal of Industry Applications, May 2024, [Reviewed]
Temperature dependence of impedance spectrum of charge-transfer processes in lithium-ion batteries with nickel-manganese-cobalt cathode and graphite anode
Y. Inui; S. Hirayama; T. Tanaka, Elsevier
Journal of Energy Storage, Nov. 2021, [Reviewed]
Performance Simulation of Tubular Segmented-in-series SOFC,Using Simplified Equivalent Circuit
S. Yoshida; T. Tanaka; Y. Inui
ECS Transactions(17th International Symposium on Solid Oxide Fuel Cell), Jul. 2021, [Reviewed]
Numerical Simulation of Planar SOFC Single Cell Fueled by Hydrogen, Nitrogen and Water Vapor Considering Fuel Gas Leakage From Cell Side
T. Tanaka; Y. Inui; G. Pongratz; V. Subotić; C. Hochenauer, Lead
ECS Transactions(16th International Symposium on Solid Oxide Fuel Cell), 2019, [Reviewed]
Evaluation of energy saving performance of residential SOFC CGS with heat pump water heaterYoshitaka Inui; Tadashi Tanaka; Satoshi Hirayama; Daisuke Ito, Recently, residential solid oxide fuel cell cogeneration system (SOFC CGS) has been put to the practical use. Considering this fact, in the present study, the authors evaluated the energy saving performance of the residential SOFC CGS. At first, the authors discussed what type of the back-up boiler is suitable for the residential SOFC CGS, and decided to focus on the heat pump water heater. Next, the authors carried out simulations of the operation pattern and performance of the residential SOFC CGS with heat pump water heater (SOFC/HP system) by using the measured results of the electric and hot water loads of an apartment in Fukuoka. As the nominal electric efficiency (LHV base) of the SOFC CGS, two cases of 50% and 60% were supposed. Performance simulations of the actually used residential systems of the conventional system with gas water heater, the all-electric system with heat pump water heater and the SOFC CGS with gas water heater (SOFC/GS system) were also carried out for comparison, It was made clear that the SOFC CGSs generally exhibit very high annual total energy efficiency. It is worthy of special mention that the total energy efficiency of the residential SOFC/HP system with the nominal electric efficiency of the SOFC CGS of 60% reaches one step higher level among them and exceeds the highest level of that of the SOFC/GS system., Institute of Electrical Engineers of Japan
IEEJ Transactions on Power and Energy, 2018,
[Reviewed] Energetic analyses of installing SOFC co-generation systems with EV charging equipment in Japanese cafeteriaT. Tanaka; H. Kamiko; K. Akiba; S. Ito; H. Osaki; M. Yashiro; Y. Inui, Energetic feasibility analyses were conducted when an SOFC CGS with EV charging equipment is installed in a facility with a high hot-water demand and a high thermo-electric demand ratio. The university cafeteria located on the Hitachi Campus of Ibaraki University in Japan was selected as an installation target because its electric and hot-water demands fulfilled the intended criterion of a high thermo-electric demand ratio. It was made clear that the merits of a co-generation system are not optimal in the case a gas water heater is selected as the backup hot-water supply. To solve the problems contributing to this bad result and to improve the performance, the authors next selected a heat pump water heater as the backup hot-water supply. It was made clear that this system possesses sufficiently high energy savings performance. It was also shown that the coexistence and co-prosperity of the cafeteria and EV charging equipment are successfully achieved. These results reveal that an SOFC CGS with EV charging equipment can be a feasible candidate for a future energy supply system installed in Japanese cafeteria, which is a facility with a large hot-water demand and a high thermo-electric demand ratio, by adopting a heat pump water heater, instead of the usual gas water heater, as the backup hot-water supply., PERGAMON-ELSEVIER SCIENCE LTD
ENERGY CONVERSION AND MANAGEMENT, Dec. 2017,
[Reviewed] Investigation of degradation and voltage response of lithium-ion battery based on impedance and electromotive force measurementYoshitaka Inui; Shinichi Sakamoto; Tadashi Tanaka, Detailed information on degradation process of lithium-ion batteries is essential to manage the batteries throughout their lifetime because degradation of the batteries associated with long-term usage is inevitable. To evaluate degradation degree of the batteries in detail, it is necessary to separately make clear the decrease in output power due to the increase in AC impedance and the decrease in battery capacity caused by the decrease in electromotive force. In this study, therefore, the authors at first propose a new evaluation method of detailed degradation process of lithium-ion batteries through measurements of AC impedance and electromotive force of degraded batteries. It is made clear that this proposed evaluation method can provide simple but detailed diagnosis of battery degradation degree, indicating usefulness of the proposed method. Next, as a first step for performance simulation of degraded lithium-ion batteries, the authors make clear that the already developed simulation method of battery transient voltage response, validity of which has been confirmed only for new batteries, is also applicable to degraded batteries., Institute of Electrical Engineers of Japan
IEEJ Transactions on Power and Energy, 2016,
[Reviewed] Development of PV Performance Evaluation Equipment Using Xe Flash Lamp and CR Series Circuit
T. NAGAYAMA; A. SUGAYA; N. IWATA; T. TANAKA; Y. Inui
The International Conference on Electrical Engineering 2016, 2016, [Reviewed]
Accurate and versatile simulation of transient voltage profile of lithium-ion secondary battery employing internal equivalent electric circuitT. Tanaka; S. Ito; M. Muramatsu; T. Yamada; H. Kamiko; N. Kakimoto; Y. Inui, This paper presents a new numerical simulation method to calculate transient voltage profiles of lithium-ion secondary batteries. The method employs circuit analysis of an internal equivalent electric circuit composed of an electromotive force, an LR parallel circuit, and eight CR parallel circuits. To demonstrate the accuracy and versatility of this approach, the authors measured the transient voltage responses of three types of test batteries with different output power densities, and compared these experimental data with simulation results. Battery performance was tested using different charge/discharge current patterns and a range of values for state of charge (SOC) and operating temperature. The accuracy of the proposed simulation method was confirmed for all test cases using the three different batteries and charge/discharge current patterns, demonstrating that the method is versatile and applicable to various lithium-ion secondary batteries regardless of type. Since the employed internal equivalent electric circuit is composed of only DC voltage source and linear R, L and C elements, all of general purpose software for electric circuit simulations can easily deal with the circuit. This advantage and the obtained results indicate that the proposed simulation method is a useful technique and offers a powerful tool to develop sophisticated battery control systems for various applications. (C) 2015 Elsevier Ltd. All rights reserved., ELSEVIER SCI LTD
APPLIED ENERGY, Apr. 2015
Energetic analysis of SOFC co-generation system integrated with EV charging station installed in multifamily apartmentT. Tanaka; H. Kamiko; T. Bando; A. Zaffirah; N. Kakimoto; Y. Inui; T. Maeda, The authors propose a solid oxide fuel cell (SOFC) co-generation system integrated with an electric vehicle (EV) charging station. To examine the feasibility of the proposed system, the authors numerically simulated the operation pattern of the proposed system, using the electric and thermal demands measured at a multifamily apartment from May 2003 to April 2004. Based on the simulation results, the authors calculated the overall efficiency of the system as well as the primary energy saving rate. The available electric energy for EV charging was also evaluated for the case of the proposed system installed in the multifamily apartment. As a result, it is made clear that the annually averaged overall efficiency reaches about 77% (LHV) and the expected primary energy saving rate exceeds 30% throughout the year. In addition, it is also found that sufficient amount of electric energy for EV charging can be obtained from the proposed system. Therefore, it can be concluded that the proposed SOFC system can successfully combine electrical/thermal energy co-generation and electric vehicle charging while maintaining high energy efficiency and good matching to energy consumption patterns. Crown Copyright (c) 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved., PERGAMON-ELSEVIER SCIENCE LTD
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, Mar. 2014,
[Reviewed] Energetic Analysis of SOFC Co-generation System Integrating with Charging Stand for Electric VehicleH. Kamiko; T. Tanaka; T. Bando; Z. Ayshah; N. Kakimoto; Y. Inui, The authors propose an SOFC (Solid Oxide Fuel Cell) co-generation system integrating with charging stand for EV (Electrical Vehicle) in this study. In order to study the feasibility of the proposed system, the authors calculate whole energy efficiency and amount of available electric energy for EV charging in the case the proposed SOFC co-generation system integrating with charging stand for EV is installed in an actually existing multifamily apartment. To get the whole energy efficiency and the amount of available electric energy for EV charging, the electric and thermal demands measured at the multifamily apartment from 2003 to 2004 are compared with the numerically obtained electric and thermal energy supplied from the proposed system. As a result, it is made clear that the whole energy efficiency reaches 75 % (LHV). In addition, it is also found that sufficient electric power for EV charging can be obtained from the proposed system. Therefore, it can be concluded that the proposed SOFC system, which plays roles of both co-generation and charging stand for EV, is reasonable from the viewpoint of both the energy efficiency and energy consuming pattern., IEEE
IEEE POWERTECH 2013, 2013,
[Reviewed] Numerical Simulation of Intermediate-temperature Disk Type Seal-less SOFC Fed with Partially Reformed MethaneT. Tanaka; Y. Inui; N. Chitose, Lead, Since natural gas containing methane as major component is the most promising fuel for the solid oxide fuel cell (SOFC), development of a numerical simulation code of the intermediate-temperature disk-type seal-less SOFC for methane fuel case is considered to be very useful. In this study, therefore, we develop a new simulation code for the single cell unit of this type of SOFC fed with partially reformed methane as the fuel gas, based on the existing simulation code for pure hydrogen. We calculate the current density versus single cell voltage (i-V ) curves of the single cell unit for various cases with a wide range of the cell temperature and prereformer temperature conditions and compare them with the corresponding experimental results. From the results, we confirm that the numerically obtained i-V curves coincide very well with the corresponding experimental ones in all cases. The variations of the i-V curves, which depend not only on the cell temperature but also on the prereformer temperature, are successfully simulated with a sufficiently high accuracy, indicating the validity of the newly developed simulation code. We also investigate the detailed influence of the cell temperature and prereformer temperature on the cell performance on the basis of the numerically obtained gaseous partial pressure profiles in the fuel channel and Nernst potential profiles in the cell, and clarify the reason why the prereformer temperature has obvious influence on the cell performance when the cell temperature is low, though the cell performance is almost independent of the prereformer temperature when the cell temperature is high. (c) 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc., WILEY-BLACKWELL
IEEJ Transactions on Electrical and Electronic Engineering, 2013,
[Reviewed] 高出力タイプリチウムイオン二次電池のパルス充放電時の電圧応答シミュレーション
田中正志; 乾義尚; 北村保彦; 朝倉章太, Lead
電気学会論文誌Ｂ分冊, 2011, [Reviewed]
Analytical Investigation of Cell Performance of Intermediate-Temperature Disk Type Seal-Less SOFC Fueled by MethaneT. Tanaka; Y. Inui; N. Chitose, Lead, We improve the existing simulation code of the intermediate-temperature disk type seal-less SOFC for pure hydrogen to make the simulation of methane fuel case possible. By using the simulation code, the current density - cell voltage (i-V) curves of a single cell are calculated and numerically obtained i-V curves are compared with the corresponding experimental ones. Through the comparison, validity of the improved simulation code is successfully confirmed. The influence of the pre-reformer temperature and the S/C ratio on the cell performance is also investigated through numerical simulations. As a result, it is made clear that optimization of the S/C ratio is very important to achieve high performance when both the cell temperature and pre-reformer temperature are low., ELECTROCHEMICAL SOC INC
ECS Transactions(12th International Symposium Solid Oxide Fuel Cell), 2011,
[Reviewed] Investigation on Transient Voltage Response of Lithium-ion Secondary Battery Degraded by Constant Current Charge/Discharge Cycles
T. Tanaka; M. Muramatsu; T. Takagi; N. Kakimoto; Y. Inui; S. Sakamoto
The Internationa Conference on Electrical Engineering 2011, 2011, [Reviewed]
Proposal of hydrogen co-production solid oxide fuel cell power generation systemTadashi Tanaka; Yoshitaka Inui, Lead, A hydrogen co-production solid oxide fuel cell power generation system that uses methane (natural gas) as fuel and can supply both electrical power and hydrogen is newly proposed. It is made clear that the system with the electrical power generation efficiency of over 35% and the overall system efficiency of over 70% can be realized by optimally selecting the gas flow configuration and the operating conditions. The decrease in the electrical power generation efficiency by the reduction of the air outlet temperature is compensated by the increase in the hydrogen production efficiency. This indicates that the operating mode changes depending upon the air outlet temperature without deteriorating the total system performance. The system performance under the part-load operation is also investigated, and it is made clear that the sufficiently high performance operation can be expected even under the part-load condition. © 2010 The Institute of Electrical Engineers of Japan.
IEEJ transactions on power and energy, 2010,
[Reviewed] Performance analysis of intermediate-temperature disk type seal-less solid oxide fuel cell using pure hydrogen as fuel
Tadashi Tanaka; Yoshitaka Inui; Chitose Norihisa; Takashi Miyazawa; Taner Akbay, Lead, 本研究では，純水素を燃料とする低温作動ディスク型シールレスSOFCの実験用単セルの1次元過渡動作特性解析コードを開発し，その解析コードを用いたシミュレーション結果と同条件の実験結果を比較することで，開発した解析コードの妥当性を検討した。また解析コードで対象とするSOFCの特徴である，電解質であるLSGMCの電子伝導性およびシールレス構造となっているセル出口部からのガスの逆拡散が単セルの発電性能に与える影響についても検討した。
IEEJ transaction of power and energy, 2009, [Reviewed]
平板型固体酸化物燃料電池スタックの3次元シミュレーション
乾義尚; 田中正志; 菅野智義
電気学会論文誌Ｂ分冊, 2008, [Reviewed]
Three Dimensional Analysis of Planar Solid Oxide Fuel Cell Stack Considering RadiationT. Tanaka; Y. Inui; A. Urata; T. Kanno, Lead, The authors have been engaged in numerical simulations of the planar type solid oxide fuel cell (SOFC) to make clear the dependence of the cell performance on its operating conditions. Up to now, the authors have already developed the simulation codes for the one channel region and the single cell plate in its cell stack. To calculate accurately the effect of radiation heat transfer from the cell stack surfaces, however, a code that can treat the whole cell stack is necessary. In the present study, therefore, the authors newly develop a three dimensional simulator. code of the planar SOFC stack, and the detailed effect of the radiation heat transfer is investigated. It is made clear that the conventional codes are sufficiently accurate, and the newly developed whole cell stack code is not inevitable to predict the maximum cell temperature. This is because the thermal conductivity of the cell materials made of ceramics is very small, and the central part of the cell stack is almost free from the influence of radiation heat transfer. On the other hand, the stack simulation is needed to calculate accurately the cell voltage because the radiation heat transfer reduces it when the ambient temperature is low. The bad influence of low ambient temperature on the voltage is, however, small and relatively high voltage is obtained even when the ambient temperature is very low. (C) 2006 Elsevier Inc. All rights reserved., PERGAMON-ELSEVIER SCIENCE LTD
Energy Conversion and Management, 2007,
[Reviewed] Analysis of Performance Characteristics of Intermediate-temperature Disk Type SOFC Using Pure HydrogenT. Tanaka; T. Kanno; T. Nakamura; Y. Inui; N. Chitose; T. Miyazawa; T. Akbay, Lead, In this study, a one-dimensional simulation code of intermediate-temperature disk type SOFC is developed. The single cell voltage-current density characteristic curves and the temperature dependence of the single cell voltage are calculated. The numerically estimated single cell voltage is about 0.02 V higher than that of the experimental result when the electronic conductivity of the electrolyte is not taken into consideration. To address this discrepancy, the electronic resistivity of 1500 Omega cm is incorporated in the simulation code. The numerically obtained single cell voltage coincides well with the experimental one in this case. The dependence of the single cell voltage on the cell temperature is also investigated. It is made clear that the single cell voltage takes the highest value when the cell temperature is about 760 degrees C for nominal current density of 0.3 A/cm(2)., ELECTROCHEMICAL SOC INC
ECS Transactions(10th International Symposium Solid Oxide Fuel Cell), 2007,
[Reviewed] Performance Simulation of Intermediate-temperature Disk Type SOFC Using Pure Hydrogen
T. Tanaka; T. Kanno; Y. Inui; N. Chitose; T. Miyazawa; T. Akbay, Lead
The International Conference on Electrical Engineering 2007, 2007, [Reviewed]
平板型固体酸化物燃料電池の流路内ガス分圧変動に起因する交流インピーダンスの数値解析
乾義尚; 中島丈晴; 田中正志
電気学会論文誌Ｂ分冊, 2006, [Reviewed]
Performance Simulation of Planar SOFC Using Mixed Hydrogen and Carbon Monoxide Gases as Fuel
Y. Inui; A. Urata; N. Ito; T. Nakajima; T. Tanaka
Energy Conversion and Management, 2005, [Reviewed]
