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:
Jun. 01, 2004
Filed:
Apr. 17, 2002
Dieter Eckardt, Herzogenaurach, DE;
Carsten Rebbereh, Erlangen, DE;
Siemens Aktiengesellschaft, München, DE;
Abstract
In a method and device for monitoring speed, in particular for monitoring the rotation speed of an electric machine, two processors are employed which monitor the speed using different checking modes and cross-compare results. The first processor executes a conventional control algorithm and checks on the basis of an estimated or measured value of the speed whether a speed limit has been exceeded. The second processor determines the actual output frequency, which is also indicative of the speed, of a converter either from actual current values, which are measured anyway, or by reconstructing the voltage from control signals of transistors. Both processors thus monitor if a rotation speed limit has been exceeded and/or execute corresponding response actions. The method also recognizes faults in the power section based on the evaluation of the phase current. The system can also be designed to manage pulling loads.