LED开关电源中铝电解电容性能退化模型的研究

Research on the Degradation Model of Aluminum Electrolytic Capacitors in LED SMPS

应用表明铝电解电容是开关电源中故障率最高的元件,是影响开关电源可靠性的最关键因素。针对LED开关电源中的铝电解电容性能退化进行了研究,首先研究了铝电解电容的失效机理,确定退化原因及其在电路模型参数上的表现形式,然后针对某实际的LED开关电源,设计了LED开关电源在线监测系统,以获取反映开关电容退化的数据。最后根据退化数据总结开关电容的退化规律,建立起开关电容的退化模型。

The aluminum electrolytic capacitors have the greatest failure rate in switching modes power supply （SMPS）, which is one of the most critical factors affecting the reliability of SMPS. The research on the degradation of aluminum electrolytic capacitors in LED SMPS was carried out. Firstly, the failure mechanisms of aluminum electrolytic capacitors were studied and the cause for degradation and the performing forms in circuit model＇s parameters were verified. Then the on-line monitoring system for a certain LED SMPS system was designed, which is used to obtain the data reflecting the degradation of aluminum electrolytic capacitors. Moreover, the degradation regulations were acquired according to the experimental degradation data, and the degradation model for aluminum electrolytic capacitors was build up.