著者

塩井 太介 宮下 充 渡辺 大貴 日下 佳祐 伊東 淳一 中西 俊貴 小林 和博

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.520-531, 2021-07-01 (Released:2021-07-01)

参考文献数

30

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This paper proposes a multiport converter based on a flying capacitor converter topology for use in a battery management system. The proposed circuit operates in discontinuous current mode and pulse frequency modulation in order to reduce inductor volume. The circuit achieves load fluctuation compensation and maximum power point tracking of the photovoltaic (PV) system by deciding duty ratio based on load current and PV output current. According to the experimental results, an efficiency of more than 95.8% was achieved under all operation conditions. In addition, the maximum efficiency reached 98.8% at the rated load (750W). Furthermore, the inductor volume reduced by 85.5% compared to that of the conventional circuit using two inductors.

著者

塩井 太介 熊谷 崇宏 日下 佳祐 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.142, no.3, pp.198-205, 2022-03-01 (Released:2022-03-01)

参考文献数

31

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This paper proposes a low vibration stopping method by switching between the free-run and short-circuit braking modes of a compressor. Vibrations are generated by the bouncing of the rotor caused by load torque fluctuations. The proposed method suppresses the bouncing by stopping the motor during the suction process, thereby preventing the generation of a large torque. In order to stop the motor during the suction process, the proposed method switches from the free-run to short-circuit braking mode at the top dead center, which is the starting point of the suction process. Furthermore, the inrush current during the short-circuit braking mode is suppressed using a hysteresis current controller. The vibrations are evaluated under four pressure conditions using the conventional and proposed methods. The results show that, the proposed method achieves more than 50% reduction in the amplitudes of the vibrations at all four pressure conditions. Notably, the proposed method reduces the amplitude of the vibration by 71% under the high-pressure condition.

著者

熊谷 崇宏 伊東 淳一 日下 佳祐 佐藤 大介

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.12, pp.962-975, 2021-12-01 (Released:2021-12-01)

参考文献数

21

被引用文献数

1

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This paper proposes an automatic design method of typical parameters such as number of phases, number of poles, stack thickness, stator outer diameter, rotor outer diameter, and number of turns of a switched reluctance motor from the requirement of the N-T characteristic. In particular, a specific parameter related to the magnetic saturation is defined in order to arbitrarily determine how much to use the magnetic properties of the iron core material. In the proposed method, the typical motor parameters in order to realize a miniaturized volume which satisfies an input N-T characteristic are obtained by setting the parameter related to magnetic saturation, maximum electrical frequency, maximum current density, maximum copper loss, conductor slot fill factor, magnetic properties of material, and input voltage. The designed motor is analyzed using the Finite Element Method in order to validate the proposed method.

著者

桐淵 岳 財津 俊行 土井 昌志 日下 佳祐 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.3, pp.184-193, 2020-03-01 (Released:2020-03-01)

参考文献数

27

被引用文献数

5

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Servo drive motor systems using PWM inverters have become very popular in the industrial market owing to their excellent control over torque, speed and position. Recently, problems of EMI noise and complexity of wiring from 3-phase PWM inverter power line cables have become critical issues in factories. In addition, using the regenerative energy of a motor has become important. A DC bus system can be a solution to these problems and demands. However, the DC bus system for servo drives has a risk of system instability because of interference between the DC bus and the servo drives. In this paper, an impedance-based stability analysis method is proposed that can predict the stability by only using the I/O (impedance) characteristics instead of all the system properties. The experimental results show that this method is useful.