TY - JOUR
T1 - Wear-out failure analysis of an impedance-source PV microinverter based on system-level electrothermal modeling
AU - Shen, Yanfeng
AU - Chub, Andrii
AU - Wang, Huai
AU - Vinnikov, Dmitri
AU - Liivik, Elizaveta
AU - Blaabjerg, Frede
N1 - Funding Information:
Manuscript received December 10, 2017; revised March 22, 2018; accepted April 17, 2018. Date of publication April 30, 2018; date of current version December 28, 2018. This work was supported by the Ubik Solutions LLC and financed in part by the Innovation Fund Denmark through the Advanced Power Electronic Technology and Tools (APETT) project, in part by the Estonian Centre of Excellence in Zero Energy and Resource Efficient Smart Buildings and Districts under Grant 2014-2020.4.01.15-0016 of the European Regional Development Fund, and in part by the Estonian Research Council under Project PUT1443. (Corresponding author: Yanfeng Shen.) Y. Shen, H. Wang, and F. Blaabjerg are with the Department of Energy Technology, Aalborg University, 9220 Aalborg, Denmark (e-mail: [email protected], [email protected], [email protected]).
Publisher Copyright:
© 1982-2012 IEEE.
PY - 2019/5
Y1 - 2019/5
N2 - In this paper, the wear-out performance of an impedance-source photovoltaic (PV) microinverter (MI) is evaluated and improved based on two different mission profiles. The operating principle and hardware implementation of the MI are first described. With the experimental measurements on a 300-W MI prototype and system-level finite-element method simulations, the electrothermal models are built for the most reliability-critical components, i.e., power semiconductor devices and capacitors. The dependence of the power loss on the junction/hotspot temperature is considered, the enclosure temperature is taken into account, and the thermal cross-coupling effect between components is modeled. Then, the long-term junction/hotspot temperature profiles are derived and further translated into components' annual damages with the lifetime and damage accumulation models. After that, the Monte Carlo simulation and Weibull analysis are conducted to obtain the system wear-out failure probability over time. It reveals that both the mission profile and the thermal cross-coupling effect have a significant impact on the prediction of system wear-out failure, and the dc-link electrolytic capacitor is the bottleneck of long-term reliability. Finally, the multimode control with a variable dc-link voltage is proposed, and a more reliable dc-link electrolytic capacitor is employed, which results in a remarkable reliability improvement for the studied PV MI.
AB - In this paper, the wear-out performance of an impedance-source photovoltaic (PV) microinverter (MI) is evaluated and improved based on two different mission profiles. The operating principle and hardware implementation of the MI are first described. With the experimental measurements on a 300-W MI prototype and system-level finite-element method simulations, the electrothermal models are built for the most reliability-critical components, i.e., power semiconductor devices and capacitors. The dependence of the power loss on the junction/hotspot temperature is considered, the enclosure temperature is taken into account, and the thermal cross-coupling effect between components is modeled. Then, the long-term junction/hotspot temperature profiles are derived and further translated into components' annual damages with the lifetime and damage accumulation models. After that, the Monte Carlo simulation and Weibull analysis are conducted to obtain the system wear-out failure probability over time. It reveals that both the mission profile and the thermal cross-coupling effect have a significant impact on the prediction of system wear-out failure, and the dc-link electrolytic capacitor is the bottleneck of long-term reliability. Finally, the multimode control with a variable dc-link voltage is proposed, and a more reliable dc-link electrolytic capacitor is employed, which results in a remarkable reliability improvement for the studied PV MI.
KW - Electrothermal modeling
KW - photovoltaic (PV) microinverter (MI)
KW - reliability
KW - wear-out
UR - http://www.scopus.com/inward/record.url?scp=85046350255&partnerID=8YFLogxK
U2 - 10.1109/TIE.2018.2831643
DO - 10.1109/TIE.2018.2831643
M3 - Article
AN - SCOPUS:85046350255
SN - 0278-0046
VL - 66
SP - 3914
EP - 3927
JO - IEEE Transactions on Industrial Electronics
JF - IEEE Transactions on Industrial Electronics
IS - 5
M1 - 8352545
ER -