功率变换电路电解电容器故障预测方法研究.pdf

第24卷第1期
电子测量与仪器学报
b.24
2010年1月
JOURNAL OF ELECTRONC MEASUREMENTAND NSTRUMENT
DOI:10.3724/SP.J,1187.2010.00029
功率变换电路电解电容器故障预测方法研究
孙风艳王友仁崔江林华
南京航空航天大学自动化学院测试计量技术及仪器,南京210016
摘要:本文对功率变换电路中电解电容故障预测方法进行了研究,提出了一种基于快速傅立叶变换(FFT)与最小二乘
支持向量机(LS-SVM)相结合的故障预测方法。通过对电解电容失效机理进行研究,建立其等效电路故障模型,并选择等效串
联电阻(ESR)作为寿命特征参数、输出纹波电压和电容电流作为监测信号;通过FT对监测信号进行频域分析,计算ESR;利
用LS-SVM对ESR回归建模、预测。将提出的方法应用于Buck电路,对电解电容的故障进行预测。实验结果表明,该方法
可以准确的对电解电容故障进行预测。
关键词:电解电容器;故障预测;寿命特征参数;最小二乘支持向量机;快速傅立叶变换
中图分类号:1P206+.3文献标识码:A国家标准学科分类代码:460.4030
Research on failure prediction method of electrolytic
capacitor used in power conversion circuit
Sun Fengyan Wang Youren Cui Jiang Lin Hua
(College of Automatic Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China)
Abstract: Failure preiction met hod of electrolytic apacitor used in power converter circuit has been studied in
this paper. A method based on Fast Fourier Transform(FFT )and Least Squares Support Vector Machines(Ls-svm)for
the preiction of l rol ti air il s propose is, hrough the study of electrolytic capacitors failure
mechanism, the equivalent circuit model was established. Secondly, ESR was selected as the life characteristic parame-
ter, the output ripple voltage and the capacitor current were selected as monitoring signals. Then the monitoring signals
were transformed to frequency-domain space using FFT and ESR was calculated. Finally, the LS-SVM regression was
used to establish the ten of the characteristic parameter over time an o predict the future values. The proposed me-
thod is applied to Buck converter and predict the failure of electrolytic capacitor. The experimental results showed that
the method can be effectively applied in electrolytic capacitor failure prediction
Keywords: electrolytic capacitor fault prediction; life characteristic parameter; least squares support vector ma.
chines: fast Fourier transform
1引言
大功率等特点,是目前故障诊断和故障预测等领域
的研究热点和难点。在功率变换电路中,电解电
随着电子系统性能和复杂度的不断提高,其可容器由于其成本低、容量大,被广泛的应用于滤波和
靠性越来越受到人们的重视,研究其故障预测技术,电能储存、变换,但其发生故障的概率很大。大量研
对提高设备的可靠性并保障电子系统的可用性具有究表明,电解电容器在整个电路中的失效率高达
十分重要的实际意义。在电子系统中,功率变换电路60%?,其性能直接决定了电路的可靠性。因此,研
是一种特殊的电路,由于具有强非线性、难以建模、究电解电容器的故障预测技术具有十分重要的实际
本文于2009年5月收到。
章基金项目:国家自然科学基金(编号:60672034资助项目。
万方数据