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:
May. 19, 2026
Filed:
Jan. 18, 2024
Danfoss Power Electronics A/s, Gråsten, DK;
Zhi Gao, Chapel Hill, NC (US);
Stefan Schroeder, Munich, DE;
Markus Sjoblom, Holly Springs, NC (US);
Kenneth Dean, Ooltewah, TN (US);
DANFOSS POWER ELECTRONICS A/S, Gråsten, DK;
Abstract
A method for providing thermal protection for a pre-charge unit (PRC) in an electric power conversion system, such as a medium-voltage adjustable-speed drive with a step-up transformer and DC link. The method includes identifying the electrical and thermal parameters of the PRC, estimating the current through the step-up transformer of the PRC based on input voltage, and estimating the thermal level of the transformer from the current. A protection logic then compares the estimated thermal level to a pre-determined trip threshold and outputs a trip signal if the threshold is exceeded. The disclosure also covers an electric power conversion system configured to perform this thermal protection method.