| Patent application number | Description | Published |
|---|
| 20090039866 | Fiber-Optic Current Sensor With Polarimetric Detection Scheme - The current in a conductor is measured by exploiting the Faraday effect in a sensing fiber. The light returning from the sensing fiber is split into at least two parts, at least one of which is analyzed by a first circular analyzer for generating a first signal. A second part may e.g. be analyzed by a second circular analyzer, and a third part may be analyzed by a linear analyzer. By combining the signals obtained in this way, the current induced phase delay in the returning light can be measured efficiently and accurately. | 02-12-2009 |
| 20090290165 | OPTICAL HIGH VOLTAGE SENSOR - An electro-optical high-voltage sensor includes a waveguiding sensing fiber of an electro-optical material. The electrical field of the voltage to be measured is substantially parallel to the longitudinal axis of the sensing fiber. The sensing fiber carries two orthogonally polarized light waves, with the applied field affecting the birefringence between the waves. Using an electro-optical waveguiding fiber in this configuration allows the voltage between two widely spaced points to be accurately measured. | 11-26-2009 |
| 20110072858 | METHOD FOR MANUFACTURING A FIBER OPTIC CURRENT SENSOR WITH INHERENT TEMPERATURE COMPENSATION OF THE FARADAY EFFECT - A method is provided for tuning the fiber optic retarder of a fiber optic current sensor towards a desired temperature dependence, the sensing fiber is exposed to a magnetic field or corresponding electric current and the sensor signal as well as the signal's dependence on the retarder temperature are measured. From this initial sensor signal and its temperature dependence, a target sensor signal can be determined, at which the dependence on the retarder temperature equals a desired value. Then, the retarder is thermally treated until the sensor signal reaches the target value. The method obviates the need for repetitively measuring the temperature dependence during the tuning process. | 03-31-2011 |
| 20110074393 | TEMPERATURE COMPENSATED FIBER OPTIC CURRENT OR MAGNETIC FIELD SENSOR WITH INSENSITIVITY TO VARIATIONS IN SENSOR PARAMETERS - A fiber optic current or magnetic field sensor uses a sensing fiber in a coil for measuring a current or a magnetic field and has a retarder for converting between linearly polarized light and elliptically polarized light. The retardation of the retarder; its temperature dependence as well as its azimuth angle in respect to the plane of the fiber coil are optimized in dependence of the birefringence in the sensing fiber in order to minimize the influence of temperature variations and manufacturing tolerances on the overall scale factor of the sensor. | 03-31-2011 |
| 20110122654 | HIGH VOLTAGE AC/DC OR DC/AC CONVERTER STATION WITH FIBER-OPTIC CURRENT SENSOR - DC current in a high voltage AC/DC or DC/AC converter station can be measured via the Faraday effect in one or more loops of an optical sensing fiber located at the base of a bushing extending through a wall of the hall. This arrangement can exploit the base of the bushing being at ground potential, which can simplify mounting work and maintenance. | 05-26-2011 |
| 20110128655 | GENERATOR CIRCUIT BREAKER WITH FIBER-OPTIC CURRENT SENSOR - The current in a generator circuit breaker is measured using the Faraday effect of an optical sensing fiber looped around the breaker's conductor. The sensing fiber is arranged in a sensing strip, which can be mounted to the enclosure of the generator circuit breaker or to the conductor. Exemplary embodiments can have a wide measuring range and can easily be fitted to new or existing generator circuit breakers. | 06-02-2011 |
