Design of LED Lighting System Based on AC Bus Power Supply Mode with Low and Variable Frequency

Abstract

In this paper design of LED lighting system based on AC (alternating current) bus power supply mode with low and variable frequency is proposed. Mainframe output alternating current with 250V effective value and 200Hz low frequency by conversion after APFC rectification. Extension set adopting capacitor step-down mode supply electricity to 15~25W LED units. The circuit of capacitor step-down power supply has simple structure, low cost, output short circuit and less loss. As the frequency is increased from 50Hz to 200Hz, smaller capacity capacitor can be used to provide greater power, and the output voltage ripple is greatly reduced. Because of 200Hz low frequency current, the power supply system has less EMI, stable work, low cost and simple maintenance.