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. 06, 2015
Filed:
Jul. 22, 2013
Robert Bosch Gmbh, Stuttgart, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
The invention relates to an operating state circuit for driving an inverter with half-bridges having respective switching devices, which inverter supplies an n-phase supply voltage to an n-phase electrical machine via phase connections associated with the respective half-bridges, where n≧1. The operating state circuit comprises an evaluation device, which is connected to the phase connections of the inverter and to input connections of the inverter and is designed to detect an input voltage of the inverter and phase currents at the phase connections of the inverter, and a drive device which is coupled to the evaluation device and is designed to switch the inverter from a short-circuit state to a freewheeling mode on the basis of the detected input voltage, wherein the evaluation device is designed to generate a freewheeling trigger signal and to output said signal to the drive device if the detected input voltage is lower than an adjustable freewheeling threshold value, and wherein the drive device is designed to change the respective switching devices of the half-bridges to an open state after receiving the freewheeling trigger signal only when the particular phase current detected at the associated phase connection has a zero crossing or a current direction coming from the inverter.