公开(公告)号：US10859607B2

公开(公告)日：2020-12-08

申请号：US16275939

申请日：2019-02-14

Applicant: ABB Power Grids Switzerland AG

Inventor： Georg Müller ,  Klaus Bohnert ,  Andreas Frank ,  Philippe Gabus

IPC: G01R15/24 ,  G01R19/32

Abstract: A fiber optic sensor and related method are described, with the sensor including a cross-coupling element in the optical path between a polarizing element and a sensing element, but separated from the sensing element itself; with the cross-coupling element generating a defined cross-coupling between the two orthogonal polarization states of the fundamental mode of a polarization maintaining fiber guiding light from the light source to the sensing element thus introducing a wavelength-dependent or temperature-dependent sensor signal shift to balance wavelength-dependent or temperature-dependent signal shifts due to other elements of the sensor, particularly signal shifts due to the wavelength dependence of the Faraday effect or the electro-optic effect constant.

公开(公告)号：US10725073B2

公开(公告)日：2020-07-28

申请号：US15243713

申请日：2016-08-22

Applicant: ABB Power Grids Switzerland AG

Inventor： Xun Gu ,  Sergio Vincenzo Marchese ,  Klaus Bohnert ,  Andreas Frank

IPC: G01R15/24 ,  G01D5/26 ,  G01D5/353

Abstract: An interferometric sensor and related methods are provided, with a sensing element whereby a measurand induces a relative phase shift between two waves, at least one detector measuring an interference signal between the two waves, and further including a phase shift detection unit having as input the interference signal and determining a first measure representative of the principal value of the relative phase shift, and a contrast detection unit having as input the interference signal for determining a second measure representative of the cross-correlation between the two waves, and a further a processing unit for converting the first and second measures to a measurand value.

公开(公告)号：US11047885B2

公开(公告)日：2021-06-29

申请号：US16253755

申请日：2019-01-22

Applicant: ABB Power Grids Switzerland AG

Inventor： Klaus Bohnert ,  Andreas Frank ,  Yang Lin ,  Xun Gu ,  Georg Müeller

IPC: G01R15/24 ,  G01R19/32

Abstract: The optical interferometric sensor device comprises an integrated beam splitter having a first facet and a second facet with optical ports arranged therein. On the beam splitter, the beam splitting junctions as well as the optoelectronics-side ports and the sensing-side port are arranged with a mutual displacement along the direction of the first facet. This displacement reduces undesired interference effects caused by stray light. Also, a quarter-wave retarder is provided in a recess of the beam splitter with layers of soft adhesive adjacent to it in order to reduce stress.

公开(公告)号：US11143678B2

公开(公告)日：2021-10-12

申请号：US16954451

申请日：2017-12-22

Applicant: ABB POWER GRIDS SWITZERLAND AG

Inventor： Klaus Bohnert ,  Andreas Frank ,  Georg Muller ,  Lin Yang

IPC: G01R15/24 ,  G01R33/032

Abstract: In order to carry out the polarimetric detection of a measurand, light of two polarization states is passed through a sensing element, where the two states suffer a differential phase shift depending on the value of the measurand. In order to compensate for only imperfections of the device, a method is proposed that is based on calibration values obtained in a low-value regime of the measurand only. Yet the method can still be used for accurately determining higher values of the measurand.