公开(公告)号：DE59910014D1

公开(公告)日：2004-08-26

申请号：DE59910014

申请日：1999-02-12

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS ,  BRAENDLE HUBERT ,  BODOR PATRICK

IPC: G01L9/00 ,  G01L11/02

Abstract: The subject-matter of the present invention is a wavelength-coded fiber Bragg grating pressure sensor 1 which is suitable, in particular, for use in the case of high pressures and temperatures in oil drill holes. The sensor principle according to the invention is based on the fact that the hydrostatic pressure of a liquid or gaseous medium 11 is converted with the aid of a transducer 1 into a longitudinal fiber elongation or fiber compression. The transducer 1 comprises a measuring or pressure cylinder 7a which exchanges pressure with the medium 11, and a reference cylinder 7b which is shielded from the medium 11 or oppositely pressure-loaded. Temperature-compensated transducers 1 with a temperature-independent Bragg wavelength lambdB can be realized by introducing a suitable temperature dependence of the mechanical prestressing of the pressure sensor fiber 3 by selecting the materials, lengths and arrangements of the fiber holder supports 5a, 5b. A fiber Bragg grating temperature sensor 19, 20 can be provided, in addition. Also specified are transducers 1 with other cylinder arrangements 7a, 7b, and a wavelength-division multiplex configuration with several transducers 1.

公开(公告)号：BR0114748A

公开(公告)日：2003-12-23

申请号：BR0114748

申请日：2001-10-02

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS

IPC: G01L11/02

公开(公告)号：DE59905887D1

公开(公告)日：2003-07-10

申请号：DE59905887

申请日：1999-12-16

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS ,  BRAENDLE HUBERT

IPC: G01F1/44 ,  G01L1/24 ,  G01L11/02

Abstract: The present invention relates to a fiber laser pressure sensor 1 which is suitable in particular for measuring differential pressures and flow velocities v1 in oil boreholes. The fiber laser 2 according to the invention comprises two sensor fiber segments 5a, 5b subjected to different pressure loading, in which segments a birefringence proportional to the differential pressure DELTAp=p1-p2, and consequently a beat frequency, is induced between the polarization modes or spatial modes in the fiber laser 2. Exemplary embodiments with polarimetric monomode fibers 5a, 5b and/or with elliptical two-mode fibers 5a, 5b are specified. Furthermore, pressure-resistant multichamber sensor housings 25 and wavelength division multiplex arrangements are disclosed for the fiber laser pressure sensor 1. One advantage is that the pressure signal is wavelength-coded and thus highly insensitive to interference. It can be read out directly fiber-optically over large distances between the passively optical sensor head 1 and the optoelectronic measuring device 12, 17. One application concerns the measurement of a flow velocity v1 with the aid of a Venturi tube 23.

公开(公告)号：AU8946701A

公开(公告)日：2002-04-29

申请号：AU8946701

申请日：2001-10-02

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS

IPC: G01L11/02

公开(公告)号：DE10000306A1

公开(公告)日：2001-07-12

申请号：DE10000306

申请日：2000-01-05

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS ,  NEHRING JUERGEN

IPC: G01R15/24

Abstract: The current sensor has a sensor fibre (1) wound in a coil around the outside of a current conductor (S) in a Sagnac or reflexion interferometer configuration and coupled to at least one phase delay element (4,5), providing a temperature-dependent phase delay for compensating the temperature dependency of the Verdet constant of the sensor fibre.

公开(公告)号：CA2326960A1

公开(公告)日：2001-06-06

申请号：CA2326960

申请日：2000-11-28

Applicant: ABB RESEARCH LTD

Inventor： GABUS PHILIPPE ,  BOHNERT KLAUS ,  BRANDLE HUBERT

IPC: C03B37/15 ,  G02B6/10 ,  G02B6/255 ,  G02B6/34 ,  G02F1/01 ,  G02B6/16

Abstract: A method is described for producing a fiberoptic waveguide with a basic segment (11) and a phase shift segment (12), the basic segment (11) and phase shift segment (12) having fiber cores (K) of the same form and the fiber cores being aligned at a defined angle (.alpha.) to one another. In the method, use is made of an optical fiber (1) having a fiber core (K) of the abovenamed form, which fiber is twisted at least approximately by the abovenamed defined angle (.alpha.) and held fixed in this torsional position. Subsequently, a stress-relief zone (13) is heated inside the twisted fiber (1) until the torsion is released inside the stress-relief zone (13) and the basic segment (11) is produced on one side of the stress-relief zone (13) and the phase shift segment (12) is produced on the other side. In this case, the fixing of the torsional position is maintained until after solidification of the stress-relief zone (13).

公开(公告)号：NO20004276D0

公开(公告)日：2000-08-25

申请号：NO20004276

申请日：2000-08-25

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS ,  BRONDLE HUBERT ,  BODOR PATRICK

IPC: G01L9/00 ,  G01L11/02 ,  G01L

Abstract: The subject-matter of the present invention is a wavelength-coded fiber Bragg grating pressure sensor 1 which is suitable, in particular, for use in the case of high pressures and temperatures in oil drill holes. The sensor principle according to the invention is based on the fact that the hydrostatic pressure of a liquid or gaseous medium 11 is converted with the aid of a transducer 1 into a longitudinal fiber elongation or fiber compression. The transducer 1 comprises a measuring or pressure cylinder 7a which exchanges pressure with the medium 11, and a reference cylinder 7b which is shielded from the medium 11 or oppositely pressure-loaded. Temperature-compensated transducers 1 with a temperature-independent Bragg wavelength lambdB can be realized by introducing a suitable temperature dependence of the mechanical prestressing of the pressure sensor fiber 3 by selecting the materials, lengths and arrangements of the fiber holder supports 5a, 5b. A fiber Bragg grating temperature sensor 19, 20 can be provided, in addition. Also specified are transducers 1 with other cylinder arrangements 7a, 7b, and a wavelength-division multiplex configuration with several transducers 1.

公开(公告)号：NO20003406D0

公开(公告)日：2000-06-29

申请号：NO20003406

申请日：2000-06-29

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS ,  BRONDLE HUBERT

IPC: G01D5/353 ,  G01L1/24 ,  G01L11/02 ,  G02B6/02 ,  G02B6/10 ,  H01S3/06 ,  G01L

Abstract: The invention relates to a frequency-coded fiber laser pressure sensor (1) which is especially suitable for measuring isotropic pressures in oil wells. The sensor principle provided for in the invention is based on the fact that in a fiber laser (2) doped with Er a monomode or bimodal sensor fiber (5, 5a, 5b) is positioned whose pressure-related birefraction results in a frequency shift and beat frequencies between the orthogonal linear polarisation modes x, y or the spatial modes LP01 and LP11 line. The beat frequencies are easily measured using a frequency counter (19). Temperature-related variations in birefraction are compensated in a differential arrangement of two sensor fiber segments (5a, 5b). Fiber-integrated Bragg gratings (4a, 4b) with low bandwidths (0.2 nm) are especially suitable as laser end reflectors. The pressure sensor (1) is characterized by a large measurement range (100 Mpa) and a high triggering capacity , (kPa), is readily multiplexed and can be housed in a very compact, light-weight and robust pressure-resistant housing (25).

公开(公告)号：AU3244099A

公开(公告)日：1999-09-15

申请号：AU3244099

申请日：1999-02-12

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS ,  BRANDLE HUBERT ,  BODOR PATRICK

IPC: G01L9/00 ,  G01L11/02

Abstract: The subject-matter of the present invention is a wavelength-coded fiber Bragg grating pressure sensor 1 which is suitable, in particular, for use in the case of high pressures and temperatures in oil drill holes. The sensor principle according to the invention is based on the fact that the hydrostatic pressure of a liquid or gaseous medium 11 is converted with the aid of a transducer 1 into a longitudinal fiber elongation or fiber compression. The transducer 1 comprises a measuring or pressure cylinder 7a which exchanges pressure with the medium 11, and a reference cylinder 7b which is shielded from the medium 11 or oppositely pressure-loaded. Temperature-compensated transducers 1 with a temperature-independent Bragg wavelength lambdB can be realized by introducing a suitable temperature dependence of the mechanical prestressing of the pressure sensor fiber 3 by selecting the materials, lengths and arrangements of the fiber holder supports 5a, 5b. A fiber Bragg grating temperature sensor 19, 20 can be provided, in addition. Also specified are transducers 1 with other cylinder arrangements 7a, 7b, and a wavelength-division multiplex configuration with several transducers 1.

公开(公告)号：DE19807891A1

公开(公告)日：1999-08-26

申请号：DE19807891

申请日：1998-02-25

Applicant: ABB RESEARCH LTD

Inventor： BOHNERT KLAUS ,  BRAENDLE HUBERT

IPC: G01D5/353 ,  G01L1/24 ,  G01L11/02 ,  G02B6/02 ,  G02B6/10 ,  H01S3/06 ,  G01D5/28 ,  E21B47/06 ,  G02B6/124

Abstract: The fiber-laser pressure sensor (1) has a sensor fiber (5, 5a, 5b) of rotationally asymmetrical structure located between the end reflectors (4a, 4b) of the fiber-laser (2). An Independent claim is also included for a fiber-laser sensor (1) used especially for elongation or temperature measurement, comprising a double-refractive, preferably two-mode sensor fiber (5, 5a, 5b) located between the end reflectors (4a, 4b) of the fiber-laser (2).