An isolation power supply by phototransmission.
An isolation power supply by phototransmission was proposed, and the conversion efficiency and the electric characteristics of a prototype of the power supply unit were estimated. Infrared light emitting diodes (LEDs) and single-silicon-crystal solar cells were used as light sources and photovoltaic cells, respectively. A maximum conversion efficiency of 3.9% was achieved. The constant output voltage feedback system, which detects the change of the output voltage of the solar cells and controls the driving current of the LEDs, operates this power supply at maximum conversion efficiency independent of loads. The liquid-cooling structure of the power supply unit can keep the conversion efficiency nearly constant independent of the input power. The fabricated power supply has little capacitive leakage current and negligibly small internal noise.
Takahashi
K
K
Electronic Engineering, Faculty of Engineering, Saitama University, Japan.
Izawa
K
K
Morimoto
T
T
D011211:Electric Power Supplies; D004867:Equipment Design; D007259:Infrared Rays; D012993:Solar Energy