DC-side faults mechanism analysis and causes location for two-stage photovoltaic grid connected inverters

• Published in: Microelectronics and reliability Vol. 126; p. 114229
• Main Authors: Ma, Mingyao, Xiong, Pengbo, Xiang, Nianwen, Wang, Hanyu, Meng, Xuesong
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2021
• Subjects: Fault causes location; Fault mechanism; Grid connected inverter; Hardware in the loop experiment; Fault causes location; Hardware in the loop experiment; Fault mechanism; Grid connected inverter
• ISSN: 0026-2714; 1872-941X
• DOI: 10.1016/j.microrel.2021.114229

Due to the deep coupling of the DC faults for the two-stage photovoltaic (PV) inverters, it is very difficult to determine the specific causes of DC faults. In terms of this issue, the fault mechanism of different causes is analysed and the obvious fault features are selected to locate the causes. Furthermore, a complete set of fault diagnosis process is proposed for DC overvoltage and undervoltage faults. An experimental platform for PV power generation system is used to simulate the deterioration of operating conditions and obtains various fault data. The results show that the correctness of fault mechanism analysis and the effectiveness of the proposed diagnosis process. •There are multiple fault causes coupling in DC side of photovoltaic inverter.•The changes of voltage, current and power are derived by fault mechanism analysis.•The differences of failure feature are used to locate the fault cause.•Online diagnosis of DC fault without additional sensors