US 11,747,366 B2
Current sensor for non-contact current measurement
Steffen Boettcher, Hanau (DE)
Assigned to VACUUMSCHMELZE GMBH & CO. KG, Hanau (DE)
Filed by Vacuumschmelze GmbH & Co. KG, Hanau (DE)
Filed on Jan. 18, 2022, as Appl. No. 17/577,469.
Claims priority of application No. 102021104752.8 (DE), filed on Feb. 26, 2021.
Prior Publication US 2022/0276283 A1, Sep. 1, 2022
Int. Cl. G01R 15/18 (2006.01); G01R 19/00 (2006.01); H01F 27/28 (2006.01); H01F 27/24 (2006.01)
CPC G01R 15/18 (2013.01) [G01R 19/0092 (2013.01); H01F 27/24 (2013.01); H01F 27/28 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A circuit, having:
an oscillator circuit with a magnetic core with at least one primary conductor magnetically coupled to the magnetic core, and with at least one secondary conductor magnetically coupled to the magnetic core, the oscillator circuit being designed to magnetize the magnetic core regularly in opposite directions up to a maximum value by controlling the at least one secondary conductor, and which is further designed to generate an oscillator signal which alternates from a first state to a second state, or vice versa, when the maximum value is reached;
a time measuring circuit which is designed to regularly determine a first time period and a second time period that the oscillator signal dwells in the first or the second state in an oscillation period; and
an evaluation unit which is designed to determine a difference between the first time period and the second time period and, based thereon, to determine a measured value for the effective primary current flowing through the at least one primary conductor.