| 摘要 |
<P>PROBLEM TO BE SOLVED: To significantly reduce running cost by efficiently lighting a number of LEDs and simplifying maintenance while a circuit structure is very simple. <P>SOLUTION: The lighting system of a tunnel includes: a rectifier circuit 1 which rectifies full waves of an input three-phase AC power supply 9 and converts into a DC and outputs; an LED series circuit 3 connecting a plurality of LEDs 13 connected to an output side of the rectifier circuit 1 in series; a switching element 4 which is connected to the LED series circuit 3 in series, switches on and off, and adjusts a current of the LEDs 13; a coil 5 serially connected to the switching element 4; and a control circuit 6 for controlling a timing of switching on and off of the switching element 4. The lighting system of the tunnel includes a series circuit of the LED series circuit 3, the switching element 4, and the coil 5 connected to an output side of the rectifier circuit 1, and the control circuit 6 lights the LEDs 13 by switching on and off of the switching element 4. <P>COPYRIGHT: (C)2011,JPO&INPIT |
