APPARATUS FOR CONTROLLING POWER OF LED

摘要

The purpose of the present invention is to provide an LED power control apparatus capable of improving a power factor, removing light flicker and being operated in an interval with a low dimming level, for a lighting power system having a triode for alternating current (TRIAC) dimmer installed therein. For this purpose, the present invention relates to a power control apparatus of a lighting device provided with a TRIAC dimmer, a bridge oscillation circuit unit, a PFC control unit, a DC/DC converter, and an LED light-emitting unit. The power control apparatus comprises: a balance high-frequency filter unit for filtering high-frequency signals included in input power and for outputting the input power to the bridge oscillation circuit unit after balancing the input power occurred by a phase difference between the positive direction and the negative direction of the input power caused by the TRIAC dimmer; a phase detection unit for outputting either PWM output signals or DC voltage to the DC/DC converter corresponding to a phase of voltage outputted from the bridge oscillation circuit unit; and a low-voltage control unit for controlling a part of the output power of the PFC control unit to be provided as driving power of the PFC control unit, by being driven if the output power of the PFC control unit lowers less than or equal to specific voltage. Therefore, the present invention can remove ripple of output power so as to remove light flicker that changes by time, and maintain a high power factor even if an input voltage phase of the TRIAC dimmer is controlled, and provide, even in low power voltage, stable power for the circuit unit for driving the PFC.