A new low-cost energy-saving concept in the modern light-emitting diode (LED) illumination system is developed and implemented using an isolated single-ended primary inductance converter (SEPIC). The dimming scheme presented in this study is a single-step with negligible distortion in the AC mains current as compared to the traditional low-cost triode for alternating current (TRIAC) dimming system, which distorts the AC mains current wave-shape beyond sinusoidal nature due to the phase-cut techniques. This dimming concept is completely retrofitted, no additional arrangement is required to initiate the dimming as compared to a TRIAC dimmer or other controllers. The isolated SEPIC converter is modelled and analysed in detail using the state-space average technique. The stability of the designed converter and overall closed-loop control are verified using Bode-plot analysis. The full load converter efficiency is found around 93%, which is much higher than the conventional flyback topology-based LED driver. The concept presented in this study is tested with the help of a laboratory prototype with an LED load of 60 W.

中文翻译：

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使用隔离式SEPIC转换器的大功率LED照明中的新型无失真调光

使用隔离式单端初级电感转换器（SEPIC），开发并实现了现代发光二极管（LED）照明系统中的新型低成本节能概念。与传统的低成本交流三极管（TRIAC）调光系统相比，本研究中提出的调光方案是一个单步，交流电源电流的失真可忽略不计，它使交流电源电流波形失真超过正弦波性质由于采用了切相技术。此调光概念已完全翻新，与TRIAC调光器或其他控制器相比，无需额外的布置即可启动调光。使用状态空间平均技术对隔离的SEPIC转换器进行建模和详细分析。使用波特图分析验证了设计转换器的稳定性和整体闭环控制。满载转换器的效率约为93％，远高于传统的基于反激式拓扑的LED驱动器。这项研究中提出的概念是在具有60 W LED负载的实验室原型的帮助下进行测试的。