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:
Feb. 02, 2021
Filed:
Aug. 16, 2018
Alstom Transport Technologies, Saint-Ouen, FR;
Davide Barlini, Milan, IT;
ALSTOM TRANSPORT TECHNOLOGIES, Saint-Ouen, FR;
Abstract
The present invention relates to a method for determining a state of a bearing of a three phase electric machine, the electric machine having a rotor, which is supported by the bearing, the electric machine being connected to a three phase inverter for supplying the electric machine with electric power, the three phase inverter being controlled to apply a pulse width modulation with a predefined scheme to create three phase currents, the method comprises: —determining a first phase current provided to the electric machine; —determining a second phase current provided to the electric machine, the second phase current being different to the first phase current; —determining the power spectral density of the park's vector based on the first phase current and the second phase current; —determining an amplitude of the power at a predefined frequency of the power spectral density, wherein the predefined frequency depends on the rotational speed of the rotor and the scheme of the pulse width modulation; —comparing the amplitude of the power at the predefined frequency with a predefined power value; and—determining, based on the comparison, whether a failure of the bearing has occurred or the bearing is degraded.