基于维纳过程的光伏逆变器寿命评估方法

针对传统高可靠电子产品寿命评估方法难以有效获取充足的失效数据等难题,本文提出一种基于随机过程理论的光伏逆变器可靠性评估与寿命预计方法。首先,通过加速退化实验获取光伏逆变器性能退化数据,并选取输出功率作为表征其健康状态的性能参数；其次,采用典型一元维纳过程建立其性能退化模型,并利用最大似然法与贝叶斯理论更新退化模型参数；最后,依据光伏逆变器失效阈值实现其寿命估计,并预测逆变器在不同退化程度下的剩余使用寿命及其置信区间。实验结果验证了所提方法的有效性和准确性。

A Lifetime Evaluation Method Based on Wiener Process for PV Inverter

Aiming at the difficulty in obtaining sufficient failure data for the lifetime assessment of traditional high-reliability electronic products, a reliability evaluation and lifetime prediction method for photovoltaic inverters based on stochastic process theory is proposed in this paper. Firstly, the photovoltaic (PV) inverter performance degradation data is obtained by accelerated degradation experiment, as well as the output power is selected as its performance parameter. Secondly, the performance degradation model is established by the typical wiener process theory, and the maximum likelihood and Bayes method is used to estimate the degradation model parameters. Finally, lifetime estimation and remaining useful life prediction are realized according to the PV inverter failure threshold. The experimental results verify the validity and accuracy of the proposed method.