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Limitation of switching frequency to improve characteristics and suppression of input current distortion for critical mode PFC 限制开关频率以改善临界模式PFC的特性和抑制输入电流畸变
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-10-23 DOI: 10.1002/eej.23407
Ryuji Yamada, Ryunosuke Araumi, Keiji Wada
{"title":"Limitation of switching frequency to improve characteristics and suppression of input current distortion for critical mode PFC","authors":"Ryuji Yamada,&nbsp;Ryunosuke Araumi,&nbsp;Keiji Wada","doi":"10.1002/eej.23407","DOIUrl":"10.1002/eej.23407","url":null,"abstract":"<p>In critical mode power factor correction (PFC), the switching frequency is varied to achieve a sinusoidal input current waveform. Under certain conditions, a higher frequency increases the loss and noise. Meanwhile, the limitation of the switching frequency leads to an increase in input current distortion. This paper proposes a method to prevent an increase in distortion by compensating the pulse width at a limited frequency. Using this control method, critical mode PFC with a limited maximum switching frequency was evaluated. As a result, the total harmonic distortion of the input current was lower than that before the frequency limitation. Furthermore, the improvement in efficiency and the reduction in conducted EMI were confirmed.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72518592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Input voltage estimation method and suppression of distortion caused by DC voltage ripple for input current control of PFC PFC输入电流控制的输入电压估计方法及直流电压纹波畸变抑制
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-10-21 DOI: 10.1002/eej.23406
Ryuji Yamada, Ryunosuke Araumi, Keiji Wada
{"title":"Input voltage estimation method and suppression of distortion caused by DC voltage ripple for input current control of PFC","authors":"Ryuji Yamada,&nbsp;Ryunosuke Araumi,&nbsp;Keiji Wada","doi":"10.1002/eej.23406","DOIUrl":"10.1002/eej.23406","url":null,"abstract":"<p>This paper proposes a new method for input current control of power factor correction (PFC) with continuous conduction mode (CCM), which does not require input voltage detection. As a control method that does not use input voltage detection, pulse width modulation (PWM) with the inductor current as the modulated signal is already in practical use however, this approach has limitations for the range of inductance values used. In CCM-PFC, the input rectified voltage and low-frequency component of the voltage of the switching circuit are approximately equal in the stable state as well as proportional to the PWM signal. This study uses the previous modulated signal as the estimated voltage value to generate an instantaneous current command for feedback control. In addition, a method to suppress the influence of the DC voltage ripple by changing the voltage control gain according to the value of the DC voltage was employed. From the evaluation, it was confirmed that the harmonics of the input current were suppressed within the specified range of values.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88432755","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
MEMS Rogowski coil current sensor with spiral return coil 带有螺旋回线圈的MEMS Rogowski线圈电流传感器
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-10-19 DOI: 10.1002/eej.23408
Yoshiyuki Watanabe, Mutsuto Kato, Toru Yahagi, Hiroki Murayama, Naoya Yamada, Kenichi Yoshida, Kenichi Maehara, Yusuke Fukuda, Kazuyuki Sashida, Katsuya Ikeda, Kosuke Ikeda, Toshiyuki Takemori
{"title":"MEMS Rogowski coil current sensor with spiral return coil","authors":"Yoshiyuki Watanabe,&nbsp;Mutsuto Kato,&nbsp;Toru Yahagi,&nbsp;Hiroki Murayama,&nbsp;Naoya Yamada,&nbsp;Kenichi Yoshida,&nbsp;Kenichi Maehara,&nbsp;Yusuke Fukuda,&nbsp;Kazuyuki Sashida,&nbsp;Katsuya Ikeda,&nbsp;Kosuke Ikeda,&nbsp;Toshiyuki Takemori","doi":"10.1002/eej.23408","DOIUrl":"10.1002/eej.23408","url":null,"abstract":"<p>We have developed a MEMS Rogowski coil current sensor with spiral return coil. The Rogowski coil is formed on a silicon substrate clockwise and counterclockwise from the edges, for current detection and external magnetic noise compensation (device size 10 × 10 × 0.3 mm<sup>3</sup>, spiral coil 135 turns, via diameter 100 μm). When the slew rate (<i>di</i>/<i>dt</i>) was kept constant at 10 A/μs, and the current was changed by 5 A up to 40 A, MEMS Rogowski coil could detect current linearly. When the slew rate was changed by 10 A/μs up to 100 A/μs, it was found that the MEMS Rogowski coil could detect current almost linearly following the reference sensor. Hence, external noise compensation by the return coil has been confirmed.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78760966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Development of a hands-free electrolarynx for obtaining a human-like voice using the LPC residual wave 利用LPC残余波获得类人声音的免提电喉器的研制
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-10-18 DOI: 10.1002/eej.23409
Masaki Takeuchi, Yutaro Soejima, Jaesol Ahn, Kunhak Lee, Ken Takaki, Tohru Ifukube, Ken-Ichiro Yabu, Shinnosuke Takamichi, Masaki Sekino
{"title":"Development of a hands-free electrolarynx for obtaining a human-like voice using the LPC residual wave","authors":"Masaki Takeuchi,&nbsp;Yutaro Soejima,&nbsp;Jaesol Ahn,&nbsp;Kunhak Lee,&nbsp;Ken Takaki,&nbsp;Tohru Ifukube,&nbsp;Ken-Ichiro Yabu,&nbsp;Shinnosuke Takamichi,&nbsp;Masaki Sekino","doi":"10.1002/eej.23409","DOIUrl":"10.1002/eej.23409","url":null,"abstract":"<p>The conventional electrolarynx (EL) restores the voice of people who have lost their voice, however, its voice sounds like a robot and it occupies user's one hand. Therefore, we developed a hands-free wearable electrolarynx that improves the voice quality with the LPC residual wave as the vibration sound. Our device was able to reproduce sounds below 500 Hz, which is close to the fundamental frequency, but from 1700 Hz to 4000 Hz, the conventional EL continuously showed a frequency response closer to the spectrum of the user's vocal sound than our device. Thus, the periodic sound of the fundamental frequency band was found to be closer to human speech than individuality or sound quality.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82603229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Microfabrication of surface acoustic wave devices with AlN thin film deposited on half-inch quartz wafer 半英寸石英晶圆上AlN薄膜表面声波器件的微加工
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-10-14 DOI: 10.1002/eej.23412
Asahi Nagano, Kanato Kitamura, Shuichi Noda, Sunao Murakami, Kohei Iguchi, Sommawan Khumpuang, Shiro Hara
{"title":"Microfabrication of surface acoustic wave devices with AlN thin film deposited on half-inch quartz wafer","authors":"Asahi Nagano,&nbsp;Kanato Kitamura,&nbsp;Shuichi Noda,&nbsp;Sunao Murakami,&nbsp;Kohei Iguchi,&nbsp;Sommawan Khumpuang,&nbsp;Shiro Hara","doi":"10.1002/eej.23412","DOIUrl":"10.1002/eej.23412","url":null,"abstract":"<p>In this paper, we have fabricated surface acoustic wave (SAW) devices with six sets of interdigital transducers (IDTs) on half-inch wafers of quartz with deposited thin films of aluminum nitride (AlN). Firstly, AlN thin films have been deposited by reactive sputtering in Ar-N<sub>2</sub> gas mixture at 400°C with the high-power impulse magnetron sputtering (HiPIMS) system which was developed for microfabrication process in the localized clean environment with half-inch wafer (Minimal Fab). After that, IDTs of Al thin films have been prepared on the AlN thin films. The X-ray diffraction (XRD) pattern of the AlN thin films shows that the AlN films have <i>c</i>-axis (002) orientation. Furthermore, the frequency responses have been measured with four paired IDTs of the SAW devices, which were selected from six sets of IDTs as an input electrode and an output electrode. These results show device properties responding to the design of the IDTs and also suggest the potential of the fabricated SAW devices as the four-paralleled frequency filter and/or sensing system.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77526026","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Highly extendable passive current balancing interleaved high step-up boost converter using voltage multipliers 高度可扩展无源电流平衡交错高升压转换器使用电压乘法器
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-10-13 DOI: 10.1002/eej.23411
Kakeru Koyama, Masatoshi Uno, Hiroki Inohara
{"title":"Highly extendable passive current balancing interleaved high step-up boost converter using voltage multipliers","authors":"Kakeru Koyama,&nbsp;Masatoshi Uno,&nbsp;Hiroki Inohara","doi":"10.1002/eej.23411","DOIUrl":"10.1002/eej.23411","url":null,"abstract":"<p>High step-up boost converters with large input current capacity are necessary for low-voltage renewable energy sources, such as photovoltaic panels and fuel cells. Interleaved converters are a suitable topology for low-voltage, large input current applications. Conventional interleaved converters, however, face a variety of challenges, such as the necessity of additional current control loops for active current balancing, increased voltage stress of semiconductors, and poor extendibility. In this paper, highly extendable interleaved high step-up boost converters with a passive current balancing and reduced semiconductor voltage stresses are proposed. Current capacities and step-up conversion ratios of the proposed converters can be arbitrarily enhanced by extending the number of phases and voltage multiplier (VM) stages, respectively. The experimental results of 500-W prototypes demonstrated passive current balancing, reduced semiconductor voltage stresses, and enhanced step-up conversion ratios.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81692322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Development of a circuit breaker system using a linear motor with opposite magnetic poles 采用反向磁极直线电机的断路器系统的研制
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-09-25 DOI: 10.1002/eej.23388
Yasuaki Aoyama, Yu Hasegawa, Katsuhiko Shiraishi, Hiroaki Hashimoto, Hajime Urai, Daisuke Ebisawa
{"title":"Development of a circuit breaker system using a linear motor with opposite magnetic poles","authors":"Yasuaki Aoyama,&nbsp;Yu Hasegawa,&nbsp;Katsuhiko Shiraishi,&nbsp;Hiroaki Hashimoto,&nbsp;Hajime Urai,&nbsp;Daisuke Ebisawa","doi":"10.1002/eej.23388","DOIUrl":"10.1002/eej.23388","url":null,"abstract":"<p>The high-thrust linear motor with a lightweight and high-strength mover was developed for operating circuit breakers. The linear motor is composed of a lightweight mover that has permanent magnets sandwiched between magnetic poles and an armature with a three-dimensional magnetic circuit. The specifications and performance of the linear motor were determined to cut off current soundly. Then, a prototype of a fully electrically operated breaker using linear motor was investigated. The linear-motor-based operating mechanism designed for the circuit breaker reached the open-pole position in 13.2 ms from the start of movement. However, the time from opening to 0.5 cycle was 9.0 ms. In addition, the variation in breaking operation time was within 1 ms, which was expected that stable controlled operation.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77331799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Energy mix for net zero CO2 emissions by 2050 in Japan 到2050年，日本实现净零二氧化碳排放的能源结构
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-09-20 DOI: 10.1002/eej.23396
Takashi Otsuki, Hideaki Obane, Yasuaki Kawakami, Kei Shimogori, Yuji Mizuno, Soichi Morimoto, Yuhji Matsuo
{"title":"Energy mix for net zero CO2 emissions by 2050 in Japan","authors":"Takashi Otsuki,&nbsp;Hideaki Obane,&nbsp;Yasuaki Kawakami,&nbsp;Kei Shimogori,&nbsp;Yuji Mizuno,&nbsp;Soichi Morimoto,&nbsp;Yuhji Matsuo","doi":"10.1002/eej.23396","DOIUrl":"10.1002/eej.23396","url":null,"abstract":"<p>This study investigated cost-effective energy strategies for realizing net zero CO<sub>2</sub> emissions in Japan by 2050, employing an energy system optimization model with hourly electricity balances. The detailed temporal resolution enables the model to capture the intermittency of variable renewable energy (VRE) and the costs of system integration measures. Siting constraints on VRE, such as prohibiting solar PV and onshore wind developments in forests and offshore wind developments inside fishery rights areas, are incorporated in the model to reflect the environmental protection and social acceptance perspectives. Simulation results imply that a well-balanced power generation mix, combining renewables, nuclear, gas-fired with carbon capture and storage, as well as ammonia-fired, would contribute to curbing mitigation costs. In contrast, a simulation case with very high VRE penetration poses economic challenges. The average shadow price of electricity in 2050 in a 100% renewables case (RE100) is projected to be more than doubled from a reference case which is based on middle-of-the-road assumptions. Marginal CO<sub>2</sub> abatement cost in 2050 increases from 49,200 JPY/tCO<sub>2</sub> in the reference case to 75,300 JPY/tCO<sub>2</sub> in the RE100 case. The economic viability of high VRE penetration is improved by relaxing the siting constraints, although it may raise environmental and social concerns.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91235863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Verifying the calculation approach for radial suspension force based on the airgap flux density for SPM, consequent-pole, and bearingless AC homopolar motors 验证了基于气隙磁通密度计算SPM、结果极和无轴承交流同极电机径向悬浮力的方法
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-09-11 DOI: 10.1002/eej.23404
Takahiro Noguchi, Hiroya Sugimoto, Yusuke Fujii, Akira Chiba
{"title":"Verifying the calculation approach for radial suspension force based on the airgap flux density for SPM, consequent-pole, and bearingless AC homopolar motors","authors":"Takahiro Noguchi,&nbsp;Hiroya Sugimoto,&nbsp;Yusuke Fujii,&nbsp;Akira Chiba","doi":"10.1002/eej.23404","DOIUrl":"10.1002/eej.23404","url":null,"abstract":"<p>In this paper, a calculation method is proposed for the radial suspension force of a bearingless motor with a surface-mounted permanent magnet (SPM) rotor, a consequent-pole permanent magnet (CPM) rotor, and a homopolar permanent rotor (HPM). The radial suspension forces are calculated mathematically and analytically using the airgap flux density. It was confirmed that the proposed radial force equations are practical to calculate the suspension force based on the airgap flux density. The CPM bearingless motor and bearingless AC HPM have salient pole rotors that interact with the 2-pole Magnetomotive force (MMF) to generate 6- and 10-pole components. As a result, the radial suspension force of the CPM bearingless motor is generated by 8- and 6-pole, and 8- and 10-pole magnetic flux, whereas the bearingless AC HPM produces the radial suspension force by DC and 2-pole components. The shaft torque, the suspension force, and efficiency were also compared for SPM, CPM bearingless motors, and bearingless AC HPM. Consequently, the torque value of the CPM bearingless motor is quite close to SPM bearingless motor. Moreover, the suspension force of the CPM bearingless motor is quite close to bearingless AC HPM.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87467859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Novel dynamic wireless power transfer system using in-tire and in-wheel repeater coil for battery electric vehicles 基于轮内转发器线圈的新型电动汽车动态无线电力传输系统
IF 0.4 4区 工程技术
Electrical Engineering in Japan Pub Date : 2022-09-08 DOI: 10.1002/eej.23399
Hayato Sumiya, Eisuke Takahashi, Nobuhisa Yamaguchi, Keisuke Tani, Osamu Shimizu, Sakahisa Nagai, Hiroshi Fujimoto, Daisuke Gunji, Isao Kuwayama
{"title":"Novel dynamic wireless power transfer system using in-tire and in-wheel repeater coil for battery electric vehicles","authors":"Hayato Sumiya,&nbsp;Eisuke Takahashi,&nbsp;Nobuhisa Yamaguchi,&nbsp;Keisuke Tani,&nbsp;Osamu Shimizu,&nbsp;Sakahisa Nagai,&nbsp;Hiroshi Fujimoto,&nbsp;Daisuke Gunji,&nbsp;Isao Kuwayama","doi":"10.1002/eej.23399","DOIUrl":"10.1002/eej.23399","url":null,"abstract":"<p>In order to improve the mileage per charge of battery electric vehicles (BEV), dynamic wireless power transfer systems are being developed. There are some problems such as is the wide gap between coils when mounted under the floor of a vehicle, and the effect of foreign objects between coils on power transmission. In-wheel coils, in which the coils are placed inside the wheel, have been proposed as a solution to these problems. However, they a plastic wheel such as CFRP and cannot reduce the gap between coils. In this paper, we propose a coil configuration in which the coils are placed inside the tire and the wheel. This configuration has the advantage of using a conventional aluminum to reduce the gap between coils. The effectiveness of this method is demonstrated via simulations and experiments.</p>","PeriodicalId":50550,"journal":{"name":"Electrical Engineering in Japan","volume":"215 4","pages":""},"PeriodicalIF":0.4,"publicationDate":"2022-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75090766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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