单级无桥Sepic谐振LED驱动电路及其APWM-PFM混合控制  

Single-stage bridgeless Sepic resonant LED driver and its APWM-PFM hybrid control strategy

作　　者：林中寅 林维明[1] 黄舒晨 郑勇[1] LIN Zhongyin;LIN Weiming;HUANG Shuchen;ZHENG Yong(Fujian Key Laboratory of New Energy Generation and Power Conversion,Fuzhou University,Fuzhou 350108,China)

机构地区：[1]福州大学福建省新能源发电与电能变换重点实验室,福建福州350108

出　　处：《电机与控制学报》2024年第9期106-124,共19页Electric Machines and Control

基　　金：福建省科技厅高校产学重大项目(2014H6012)。

摘　　要：针对传统两级式LED驱动电源中存在着半导体功率器件数目多,控制电路复杂,效率低,成本高,可靠性差等问题,提出一种单级无桥Sepic谐振LED驱动电路,通过将单开关无桥Sepic电路主开关管与半桥LLC电路下开关管复用集成单级LED驱动电路,减少了半导体功率器件数目,简化控制电路,提高了电路效率和工作可靠性。详细分析了所提出电路的工作原理和工作过程,深入开展了电路输入输出电压变比、网侧特性、软开关特性等稳态特性推导和电路关键参数设计,并针对所提出单级电路由于输入电压变化引起直流母线电压变动范围大等问题,分析设计了一种APWM-PFM混合控制策略。最后进行计算机仿真分析,并设计一台交流输入185~265 V_(rms)、额定输出2 A/96 W的实验样机,样机效率最高可达91.5%,PF最大值为0.995,THD最小为5.5%,不同交流电压下直流母线电压总体变化范围在60 V以内,实现直流母线电压限压。计算机仿真结果和实验结果验证所提出电路和混合控制策略的理论预期和有效性。Because of the existence of many power devices,complex control circuits,low efficiency,high cost and poor reliability,etc.in the traditional two-stage LED driver,a single-stage bridgeless Sepic res-onant LED driver was proposed,which is integrated by multiplexing the switching tube of the single-switch bridgeless Sepic circuit and the lower switching tube of the half-bridge LLC circuit.The operating principle and the operating process of the proposed circuit were analyzed.The steady-state characteristics of the proposed driver,such as voltage variable ratio,the line characteristics and soft-switching character-istics were analyzed in detail;then the proposed circuit’s key parameters were designed in detail.And a hybrid APWM-PFM control strategy was designed for single-stage circuits with a wide range of DC bus voltage variations caused by the change of input voltage.Finally,the computer simulation was carried out and an AC input 185-265 Vrms,rated output 2 A/96 W experimental prototype was set up.The efficien-cy of the prototype is obtained to be up to 91.5%,the maximum value of PF is obtained to be up to 0.995,and the minimum value of THD is obtained to be down to 5.5%,under the case of 265 Vrms AC input,the bus voltage can be controlled and the overall variation range to be within 60 V under different AC input voltages.The results of the computer simulation and the experiment have been obtained to verify the theoretical expectations and the validity of the proposed circuits and the hybrid control strategy.

关 键 词：LED照明 功率因数校正 单级无桥Sepic/LLC电路 软开关 直流母线电压APWM-PFM混合控制 

分 类 号：TM46[电气工程—电器]