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:
Apr. 10, 2007
Filed:
Feb. 24, 2006
Gary Randolph Fisher, Los Angeles, CA (US);
Gary Randolph Fisher, Los Angeles, CA (US);
Other;
Abstract
Two apparatuses are disclosed for controlling the speed of an AC synchronous motor-pump utilizing a series of stepped voltage pulses at the driving frequency. The first apparatus is an isolated variable frequency drive comprising step-down transformer, full wave rectifier and filter, micro-controller, driving-voltage array generator, gate driver, inverter bridgeand step-up transformer. The second apparatus is a non-isolated high voltage variable frequency drive comprising full wave rectifier and filter, low voltage, dual output power supply, micro-controller, driving-voltage array generator, gate driverand inverter bridge. Methods are given to determine voltage array values and pulse times to generate a stepped voltage approximation of a sine wave driving waveform.