| 摘要 |
PROBLEM TO BE SOLVED: To reliably and continuously light an LED(light emitting diode) by reducing a capacitance of a capacitor used in a smoothing circuit and suppressing a ripple current flowing into the capacitor in an LED lighting system used in a luminaire equipped with an inverter ballast. SOLUTION: This LED lighting system consists of a full wave rectifying circuit 41 to rectify a high frequency current from an inverter ballast, a smoothing capacitor 43 connected to the rectifying circuit through an inductance element 42 and an LED unit 44 in which n×m pieces of LED 11 connected to the smoothing capacitor are arranged. If a current and a voltage drop are set for 1 min. ampere and V min volt respectively at the time when the LED starts lighting and the maximum rated forward current and voltage drop are set for 1 max. and V max. respectively, the smoothing capacitor is set to have a capacitance to always maintain a higher output voltage than (n) v min. and a lower voltage value than (n) V max. when the LED is lighted, and the inductance element is set for a value to have a sufficient impedance value at a twice as much frequency from the ballast. |
