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:
Mar. 21, 2023
Filed:
Jul. 22, 2020
Method for determining rectifier-stage output current or grid-side currents of a frequency converter
Danfoss Power Electronics A/s, Gråsten, DK;
Henrik Rosendal Andersen, Graasten, DK;
Danfoss Power Electronics A/S, Gråsten, DK;
Abstract
A method for determining rectifier-stage output current and/or grid-side currents (iu, iv, iw) of a frequency converter () having a passive rectifier (), an inverter (), a DC-link with a DC-link inductor (Ldc) and a DC-link capacitor (Cdc) between the rectification stage () and the inverter stage () is described. In a frequency converter the current information for the grid-side currents (iu, iv, iw) should be obtained without a current sensor at the grid-side (). To this end the method comprises the step of calculating a current in the DC-link () by using at least a voltage value (Urec) and characteristics of the rectifier () in the DC-link () and/or grid side currents to form a corrected current using the calculated current and a measured current or currents or a fraction of a measured current or currents, or a fraction of a measured current or currents.