著者
赤津 観 涌井 伸二
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.127, no.11, pp.1171-1179, 2007-11-01 (Released:2007-11-01)
参考文献数
10
被引用文献数
8 20

This paper proposed a calculation method of the torque and power density especially for the fractional-slot concentrated winding machines. The torque coefficient and the inductance coefficient to transform from m-slot/n-pole machine to 3-phase/2-pole machine are used. Some machines were designed and these torque densities and power densities are compared. Experimental results showed the effectiveness of the proposed calculation method and have good accordance with both calculation results and FEA results.
著者
藤井 保和 久須美 俊一 福谷 隆宏 岩井中 篤史
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.124, no.10, pp.1073-1079, 2004 (Released:2005-01-01)
参考文献数
22

This paper proposes an arc contact loss rate estimating method for Shinkansen trains with pantographs connected to bus cables. For the speedup of Shinkansen, it is necessary to judge whether the contact loss rate exceeds its standard value. As the standard of contact loss rate is provided from the viewpoint of contact strip wear caused by arcs, it is important to measure the amount of arc. The optical type contact loss measuring method which detects the contact loss by arcs is suitable for this purpose. It is difficult, however, to measure contact loss by this method in the daytime, because of the influence of outdoor light. To solve the above problem, we have developed an arc contact loss rate estimating method by using a contact loss simulation program on the basis of the complete contact loss rate measured by the current type contact loss measuring method which is effective in the daytime. Furthermore, we measured the contact loss rate simultaneously by the current and optical type contact loss measuring methods in the running tests of Shinkansen trains, and confirmed the validity of this estimation through a comparison of measured and simulated results.
著者
綾野 秀樹 北田 成祐 井口 雄紀 松井 義弘 伊東 淳一
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.140, no.6, pp.442-449, 2020-06-01 (Released:2020-06-01)
参考文献数
25
被引用文献数
4

This paper proposes a novel modulation technique that reduces both motor acoustic noise and switching loss. The conventional discontinuous PWM method can reduce the switching loss to a greater extent compared to the conventional three-phase modulation method; however, the acoustic noise of the motor increases. The proposed technique adjusts the zero-sequence voltage given to the voltage references in such a way that the discontinuous part of the conventional discontinuous PWM method is changed smoothly. The switching loss with the proposed technique can be reduced to 58% of that with the conventional three-phase modulation method. The experimental results show that the acoustic noise can be reduced to a greater extent with the proposed technique compared to that with the conventional discontinuous PWM method.
著者
高橋 勲 堀 和宇
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.117, no.1, pp.13-18, 1996-12-20 (Released:2008-12-19)
参考文献数
4
被引用文献数
3 24

This paper proposes a high power facter rectifier composed of only passive devices. It consists of a single phase diode rectifier having a L-C resonant circuit in parallel with the diode output and a series reactor to pumping up the charge stored in the resonant circuit capacitor. It enables wide current conduction width and decreases its peak value. As a result, harmonics in the input current is decreased and the power factor is improved, which will be satisfied the harmonic regulation enforced in near future.The absence of switching devices as FETs makes high reliability, high efficiency, strength to over load, and no radio noise. In this paper, it is shown input harmonic current components, output voltage, and other characteristics by charts for circuit design. Input power factor of 98.4%, the total harmonic distortion of 17.4%, and the efficiency of 93.3% are confirmed by experiment with rated condition of 1.0kW, 100V system.
著者
宮脇 慧 伊東 淳一 岩谷 一生
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society (ISSN:09136339)
巻号頁・発行日
vol.130, no.1, pp.43-50, 2010-01-01
参考文献数
11
被引用文献数
5 4

This paper proposes a high efficiency isolated DC/DC converter using series compensation. The proposed converter consists of a high efficiency resonance half-bridge converter and a series converter. The proposed circuit regulates the output voltage by the series converter, which provides only differential voltage between the input voltage and output voltage. Therefore, the circuit achieves high efficiency when the input voltage is close to the output voltage, because only the resonance converter operates.<br>In this paper, the approach used to obtain high efficiency with the proposed series compensation method is introduced. In addition, the fundamental operation and the design method of the proposed circuit are described. The validity of the proposed circuit was confirmed by experiment and loss analysis, with a maximum efficiency of 95.8%.
著者
竹上 栄治 樋口 幸治 中野 和司
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society (ISSN:09136339)
巻号頁・発行日
vol.129, no.12, pp.1137-1146, 2009-12-01
参考文献数
14

Robust DC-DC converter that can function with a single controller over a wide range of load and input voltages is required. In such a case, changes in the output voltage must be suppressed. We propose an aproximate two-degree-of-freedom (2DOF) digital controller that realizes the start-up response and dynamic load response independently. The controller makes the control bandwidth wider and suppresses the variations that occur in the output voltage due to sudden changes in loads and input voltages. In this paper, a new approximate 2DOF digital controller that involves the additinal zeros is proposed. The controller greatly suppresses the variations that occur in the output voltage due to sudden changes in loads and input voltages. This controller is actually implemented on a digital-signal-controller (DSP) and is connected to a DC-DC converter. Experimental studies demonstrate that this digital controller can satisfy the given specifications.
著者
宮脇 慧 伊東 淳一 岩谷 一生
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society (ISSN:09136339)
巻号頁・発行日
vol.133, no.9, pp.876-884, 2013-09-01
参考文献数
23

This paper discusses a bidirectional isolated DC/DC converter using the series compensation method. The proposed converter consists of a high efficiency resonance full-bridge converter and a series converter. This proposed circuit regulates the output voltage by the series converter, which provides only the differential voltage between the input voltage and the output voltage, which is close to the nominal voltage.<br>In this study, four types of auxiliary circuits are investigated in terms of loss. The relationship between the loss element and efficiency characteristics is clarified. The validity of the proposed circuit is confirmed by the loss calculation. Moreover, the experimental results confirmed that the proposed circuit, which converts 48V to 380V at 1kW, achieves a maximum efficiency of 95.5% at the nominal input voltage region.
著者
宮脇 慧 伊東 淳一 岩谷 一生
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌. D, 産業応用部門誌 (ISSN:09136339)
巻号頁・発行日
vol.131, no.10, pp.1175-1183, 2011
被引用文献数
1 2

This paper proposes a new circuit topology for a high efficiency isolated DC/DC converter using series compensation. The proposed converter consists of a high efficiency resonance half-bridge converter and a series converter. The series converter regulates the output voltage the provides only the differential voltage between the input voltage and output voltage. Therefore, the circuit achieves high efficiency when the input voltage is almost equal to the output voltage, because then only the resonance converter will operate.<br>In this paper, the approach employed to achieve a high efficiency by using the proposed series compensation method is introduced. In addition, the fundamental operation and the method of designing the proposed circuit are described. The suitability of the proposed circuit was confirmed by performing an experiment and loss analysis, maximum efficiency achieved was 96.2%.
著者
木村 雄希 岩谷 一生 栁 洋成 宮崎 敏昌
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.140, no.5, pp.372-377, 2020

<p>The use of triple active bridge (TAB) converters in distributed electric grids has attracted considerable attention because of their multi-directional power connection, insulation performance, and small size. However, there remains a problem with respect to the interaction between two current loops with TABs, and there are few solutions to this problem when an AC supply is connected to the system. In this paper, we propose a method to suppress the interference by using iterative control as the main approach, taking into account the occurrence of periodic disturbance in the TAB converter when connected to an AC system. In order to estimate the characteristics of the proposed method, a prototype is built and tested experimentally. As a result, it is confirmed that the measured grid current THD is within 5% and that he battery current ripple decreased by 84% at a maximum.</p>
著者
宮脇 慧 伊東 淳一 岩谷 一生
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌. D, 産業応用部門誌 = The transactions of the Institute of Electrical Engineers of Japan. D, A publication of Industry Applications Society (ISSN:09136339)
巻号頁・発行日
vol.133, no.3, pp.360-367, 2013-03-01
参考文献数
14
被引用文献数
2

This paper proposes a design procedure in the efficiency of a resonant type half-bridge converter for a high efficiency isolated DC/DC converter. The design procedure is based on the loss calculation. The relationship between the loss element and the efficiency characteristics was clarified. The loss analysis method based on the parameters of the circuit element is formulated. The analysis results agree well with experimental results. In addition, the highest efficiency of 96.8% is obtained using the half-bridge converter. Finally, design procedure in the efficiency was clarified using a design procedure flowchart.
著者
野中 作太郎
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.114, no.6, pp.631-637, 1994-06-20 (Released:2008-12-19)
参考文献数
18
被引用文献数
5 6

A suitable single-phase inverter for the utility interactive photovoltaic generation system is proposed. The single-phase PWM current source inverter has a novel circuit configuration which is added a auxiliary branch to the normal single-phase bridge circuit. In order to reduce the size and weight of the dc reactor, a double frequency parallel resonance circut (LC tank circuit) is inserted in the dc side of the inverter. In result, the double frequency voltage appeared in the dc side of the inverter due to the pulsation of the single-phase instantaneous power is perfectly suppressed by the tank circuit. The constant dc current without pulsation is supplied from PV array to the inverter. The inverter provide a sinusoidal ac current for domestic loads and the utility line with unity power factor.The virtual maximum power of the PV array can be obtained without any feedback control. In the system, the PV array can play an important role as a current-limitter by its V-I characteristics. Computed waveformes by simulation are shown. The excellent inverter equipment will be realized with smaller size and lighter weight than a conventional inverter.
著者
西田 保幸
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.115, no.4, pp.410-419, 1995-03-20 (Released:2008-12-19)
参考文献数
13

The harmonic pollution caused by ac-to-dc converters has been our great concern. To overcome the problem, several Power-Factor-Correction (PFC) converters have been developed and applied in practice in recent years.However, several power converter systems, such as motor drive system with a wide V/F control range, uninterruptible power supply system, and dc power supply system with an universal input voltage range, require an ac-to-dc converter or an off-line converter (pre-regurator) with a wide output-voltage control range to obtain high efficiency. But the most conventional PFC converters employ a Voltage-Fed or Current-Fed type topology and they have lower or upper limitation of the output-voltage control range. Thus, they do not realize sufficiently high system efficiency.On the other hand, a Buck/Boost converter has a wide control range of the output voltage and acts PFC operation under an appropriate control technique. Thus, the study of a possibility about the Buck/Boost ac-to-dc converter with PFC and a wide output-voltage control range is important to realize harmonic-free and efficient power conversion systems.In this paper, the author proposes a three-phase bridge-type ac-to-dc converter system with a high input power factor and a wide output-voltage control range. The controller of the proposed system includes following two new techniques. One is the “Pulse-Space-Modulation” to compensate modulation errors in conventional Pulse-Width-Modulation caused by dc current ripples or fluctuations of the current pulse amplitude. The other is a switching pulse pattern generator, using the idea of equivalent pulse current source for the bridge, to simplify the pulse pattern generation process.In the following, the paper describes the proposed converter system, the control and modulation principles, and experimental results that show the reliability and usefulness of the proposed Buck/Boost converter system. Finally, the paper concludes the contents of this paper.
著者
北原 文夫 岩本 孝雄 伊藤 聡 藤原 和紀 藤原 道雄
出版者
The Institute of Electrical Engineers of Japan
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.118, no.4, pp.534-541, 1998-04-01 (Released:2008-12-19)
参考文献数
8
被引用文献数
1 1

East Japan Railway Company (JR EAST) has developed advanced transport operation control system supporting super high-density railway in Tokyo metropolitan area. The system target is to revolutionize existing railway operation and to realize new safe and high efficient railway system. Autonomous Decentralized Transport Operation Control System has many features, including safe and steady traffic control, improved customers service and step by step system construction used by autonomous decentralized system technology. The system has been already introduced to Chuo-line in December of 1996 and is now under construction to expand to all of Tokyo metropolitan area.
著者
坂井 俊文 國廣 直希 大塚 邦晃 篠宮 健志
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.141, no.7, pp.552-560, 2021-07-01 (Released:2021-07-01)
参考文献数
24

This study presents a magnetic polarity detection method of an initial rotor position estimation for permanent magnet synchronous motor drives without a position sensor. The magnetic polarity detection method utilizes stator core magnetic saturation caused by the rotor magnet and uses current responses when a high frequency or impulse voltage is applied to the motor. Recently, capacity enlargement, miniaturization, and cost reduction of the motor have been steadily progressing and motors with complicated magnetic saturation characteristics are available. The authors have developed a new magnetic polarity detection method for initial rotor position estimation that is suitable for many motors having common or complicated magnetic saturation characteristics. In the proposed method, high-frequency voltage waves with different amplitudes are applied to the motor. The proposed method measures the motor current ripple components and can estimate the magnetic polarity by using the amount of d-axis inductance variation caused by magnetic saturation. The basic idea, computer simulation, and experimental results are discussed in this paper.
著者
沼辺 健史 西川 一弘
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.141, no.7, pp.513-519, 2021-07-01 (Released:2021-07-01)
参考文献数
10

In the future, a tsunami may occur in Japan due to a large earthquake. Railway companies must take measures for tsunami evacuation. In order to protect the lives of many people, we must ensure quick evacuation. However, train announcement for tsunami evacuation has become a major issue and currently takes too long. This study proposes train announcement for quick evacuation.
著者
松本 涼佑 奥田 大樹 深澤 紀子
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.140, no.10, pp.769-781, 2020

<p>A train schedule in Japan includes regular trains which is fixed on annual basis and pre-planned extra trains whose operation dates are not predetermined. Accordingly, in order to provide efficient transport services, a plan for the daily operation of extra trains must be established based on accurate passenger demand fluctuations forecasts by day/time. Therefore, we developed a method to forecast for the demand fluctuation by day/time on a certain day in the future. The method was developed by combining several fundamental waves, which are extracted by applying independent component analysis to actual ridership records with calendar information, and information on events which was held in target areas. We confirmed that the method has high accuracy by verifying its reproducibility and forecasting accuracy. In addition, the extra trains' operation planning system, which implements the forecasting method, can estimate the load factor of all trains between stations on the planning schedule based on the forecasted demand fluctuations. Then, the system can suggest an optimal extra trains' operation plan based on these values. We estimated the load factor based on forecasted demand fluctuations with the system, and we verified its accuracy. As a result, we confirmed that we can estimate the load factor with high accuracy.</p>
著者
弦田 幸憲 河村 篤男
出版者
一般社団法人 電気学会
雑誌
電気学会論文誌D(産業応用部門誌) (ISSN:09136339)
巻号頁・発行日
vol.125, no.11, pp.977-987, 2005 (Released:2006-02-01)
参考文献数
16
被引用文献数
4 9

We have proposed a high efficiency and high power chopper based on new soft switching scheme QRAS (Quasi-resonant Regenerating Active Snubber) and we studied the practical effectiveness and the novelty of the QRAS by the simulation and by the experiment. This time we made one-tenth prototype model actually and tested it by rating test, light load test, current discontinuous mode test and test out of resonance stable operation. We report the general evaluation of these test results and the possibility of the realization on the 80kW practical model is demonstrated by these successful test results. In addition, as an approach of the next study the feasibility test of 8kW SiC-QRAS is followed and the preliminary evaluation of efficiency rise using “Silicon Carbide (SiC)" power devices is given with the successful experimental results.