The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 26, 2025
Filed:
Jan. 31, 2023
Southeast University, Jiangsu, CN;
SOUTHEAST UNIVERSITY, Nanjing, CN;
Abstract
The present invention discloses an isolation forest (IF)-based modular multilevel converter (MMC) open-circuit (OC) fault diagnosis method, including the following steps: sampling capacitor voltages of submodules (SM), constructing an isolation tree (IT) according to capacitor voltage data, and calculating a depth of each SM in the IT; and forming an IF based on the ITs, calculating average depths of the SMs in the IF, taking an SM with the minimum average depth as an output of the IT, and finally locating a faulty SM by an output buffer to realize accurate location of the faulty SM. Only capacitor voltages of SMs are involved, and no extra hardware resources are required. System parameters are not involved, construction of a system mathematical model and manual setting of an empirical threshold are not required, and the robustness is high. Faults are located using sparsity and difference of abnormal data based on unsupervised learning, mass data analysis and sample training are not required, and the method has the advantages of linear time complexity, small data volume, simple calculation process, low calculation cost, and the like.