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:
Aug. 12, 2014
Filed:
Oct. 04, 2010
Joy Mazumdar, Norcross, GA (US);
Joy Mazumdar, Norcross, GA (US);
Siemens Industry, Inc., Alpharetta, GA (US);
Abstract
High-power synchronous motors are commonly used in mining operations, for example, in gearless draglines, gearless conveyor drives, and gearless mill drives. Substantial electromagnetic energy is stored in the inductive field windings. In the event of a system fault, such as a short in the direct current power source exciting the field windings, the electromagnetic energy needs to be discharged from the field windings. This electromagnetic energy is typically dissipated as waste heat through a resistor. Disclosed is a field discharge system in which the electromagnetic energy is captured and stored as electrical energy in a capacitor. If an ultracapacitor bank is used for storage, the charged ultracapacitor bank can be used as a backup or auxiliary power source for mining operations. The discharge time is sufficiently small that high speed circuit breakers are not needed to disconnect stator windings from the alternating current power source when a fault occurs.