著者
矢田 智春 山田 洋明 花本 剛士
出版者
パワーエレクトロニクス学会
雑誌
パワーエレクトロニクス学会誌 (ISSN:13488538)
巻号頁・発行日
vol.40, pp.168-175, 2014-03-31 (Released:2016-04-08)
参考文献数
8

This paper proposes a novel co-operational control method of LED driver, consisting of voltage and current sourced flyback converters. In the proposed method, both the flyback converters are controlled by the LED reference current to obtain wide range variable light control from 10 % to 100 %. Digital computer simulation is implemented to confirm the validity of the proposed method and demonstrate that the minimum on time of the MOSFET is longer than 1 μs even under the operation of 10 % of the LED rated current.
著者
浦山 大 平地 克也
出版者
パワーエレクトロニクス学会
雑誌
パワーエレクトロニクス学会誌 (ISSN:13488538)
巻号頁・発行日
vol.41, pp.25-33, 2015-03-31 (Released:2016-08-03)
参考文献数
6

The switching of LLC converter becomes hard switching at the time of overload. In this study, we elucidated the mechanism of hard switching and the current path. The reason of hard switching is the commutation of magnetizing current to the secondary side. It is possible to make a judgement whether overload or not from the voltage value at the end of resonance. Voltage value can be obtained from the circuit constants. In this way, it becomes possible to judge the success or failure of soft switching from the circuit constants.
著者
酒井 拓也 竹下 みゆき 菅 郁朗
出版者
パワーエレクトロニクス学会
雑誌
パワーエレクトロニクス学会誌 (ISSN:13488538)
巻号頁・発行日
vol.35, pp.184-190, 2010-04-01 (Released:2011-02-25)
参考文献数
8

We have developed the new low-loss rectification circuit that needs neither external signals nor power sources for driving. This circuit creates the control power source for the circuit operation from reverse voltage. The direction of the current that flows in this circuit is detected from the voltage between the MOSFET's drain and source. The current is rectified by driving MOSFETs using this detection result. Also, the circuit has several types of MOSFETs connected in parallel. Types and numbers of MOSFETs are automatically selected to minimize the loss according to the magnitude of the current detected from the voltage between the MOSFET's drain and source. To create the power source and the signal for the rectification circuit, the circuit needs no inputs from outside like a diode. Therefore, this circuit can be easily substituted for a conventional diode. In operation tests, the minimum forward voltage drop was 0.04 [V] when the current was rectified. As a result, the forward voltage drop was less than 1/10 compared to conventional diodes, and the loss could be decreased extremely. Therefore, the miniaturization of the electric equipment that is radiation fin and fan becomes possible, too. The low-loss rectification circuit can save energies by substituting diodes for prevention of global warming.
著者
浜岡 孝二 Hanjoo Yoo Kwangkyo Oh
出版者
パワーエレクトロニクス学会
雑誌
パワーエレクトロニクス学会誌 (ISSN:13488538)
巻号頁・発行日
vol.31, pp.116-121, 2006-03-31 (Released:2010-03-12)
参考文献数
3

Korea is the foreign country that is the nearest to Japan. However, there are a few opportunities knowing the fact unexpectedly. The market which is different from Japan is formed by a difference of a habit/appetite culture. It is a very interesting market. Therefore I introduce a refrigerator in Korea and the market and technology of inverter.