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:
Oct. 14, 2025
Filed:
Mar. 24, 2021
Mitsubishi Electric Corporation, Tokyo, JP;
National University Corporation Yokohama National University, Yokohama, JP;
Kodai Okazaki, Tokyo, JP;
Kan Akatsu, Yokohama, JP;
MITSUBISHI ELECTRIC CORPORATION, Tokyo, JP;
NATIONAL UNIVERSITY CORPORATION YOKOHAMA NATIONAL UNIVERSITY, Yokohama, JP;
Abstract
Provided is a magnetic gap length estimating device in which neither a current sensor nor a current load is necessary, and a voltage at a connection-wire neutral point does not need to be measured. A magnetic gap length estimating device for estimating a magnetic gap length in an M-group N-phase rotating electric machine to be driven by an inverter includes: a voltage acquiring unit which acquires a no-load-induced line-to-line voltage induced under no load; and a magnetic gap estimating unit. The magnetic gap estimating unit includes: a spectrum analysis unit which converts the no-load-induced line-to-line voltage acquired by the voltage acquiring unit into amplitudes and phases for respective frequencies; a frequency analysis unit which extracts amplitudes and phases of a fundamental wave component and an N-order harmonic component of the no-load-induced line-to-line voltage; and an estimating-and-calculating unit which estimates the magnetic gap length.