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:
Jan. 18, 2022
Filed:
May. 06, 2020
Bombardier Transportation Gmbh, Berlin, DE;
Johann Galic, Surahammar, SE;
Bombardier Transportation GmbH, Berlin, DE;
Abstract
A control circuit, a system and a methodof determining a position of a rotor in a permanent magnet motor PMin a state when the rotor is freely rotating, the motor being connected to a direct voltage linkvia an inverter circuit, wherein the inverter circuit is operable for connecting windings of a stator of said motor to the direct voltage link, the method comprising the following a step a) short circuitingthe windings of the stator of said permanent magnet motor, a step b) measuringa back electromotive force EMF of the short-circuited windings of the stator; and a step c) determiningthe position of the rotor by means of the measured back EMF.