LED centralized DC power supply system and operating methods thereof

摘要

The invention provides a light emitting diode (LED) centralized DC (direct-current) power supply system and operating methods thereof. The proposed DC power supply system comprises a three-phase AC (alternating-current) input interface, a DC power supply output interface, N+1 three-phase PWM (pulse width modulation) rectifier modules, LED cluster loads and a power supply management module. The proposed operating methods are described as following: the power supply management module adjusts the duty ratio of the three-phase PWM rectifier modules, based on the control signals formed by synthesizing the information about voltage and current of the positive and negative output buses, the three-phase AC input ends, control signals and output of the three-phase PWM rectifier modules, hence AC voltage of power grid can be directly converted into adjustable DC voltage by the PWM rectifier.