Optical monitoring for power grid systems

Abstract

A monitoring system for a power grid includes one or more power transformer monitors. Each power transformer monitor includes a plurality of optical sensors disposed on one or more optical fibers that sense parameters of the power transformer. Each optical sensor is configured to sense a power transformer parameter that is different from a power transformer parameter sensed by at least one other sensor of the plurality of optical sensors. An optical coupler spatially disperses optical signals from the optical sensors according to wavelength. A detector unit converts optical signals of the optical sensors to electrical signals representative of the sensed power transformer parameters.

1 . A monitoring system comprising:
 one or more power transformer monitors of a power grid system, each power transformer monitor comprising a plurality of optical sensors disposed on one or more optical fibers, the optical sensors configured to sense internal parameters of a power transformer, each optical sensor disposed at a location within or on a power transformer and configured to sense an internal transformer parameter that is different from an internal transformer parameter sensed by at least one other sensor of the plurality of optical sensors;   one or more detector units, each detector unit configured to convert optical signals of the optical sensors of a corresponding power transformer monitor to electrical signals representative of the sensed transformer parameters; and   at least one optical coupler disposed between the one or more optical fibers and the detector units, the optical coupler configured to spatially disperse optical signals from the optical sensors according to wavelength.   
     
     
         2 . The system of  claim 1 , wherein each of the optical sensors are disposed on a single optical fiber. 
     
     
         3 . The system of  claim 1 , wherein at least one of the optical sensors is disposed on a first optical fiber and at least one of the sensors is disposed on a second optical fiber. 
     
     
         4 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense core strain. 
     
     
         5 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense a dissolved gas. 
     
     
         6 . The system of  claim 5 , wherein the dissolved gas is a hydrogen-containing gas. 
     
     
         7 . The system of  claim 1 , wherein at least one of the optical sensors is a Pd-coated fiber Bragg grating. 
     
     
         8 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense temperature. 
     
     
         9 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense partial discharge. 
     
     
         10 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense transformer core strain. 
     
     
         11 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense vibration. 
     
     
         12 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense a chemical. 
     
     
         13 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense corrosion. 
     
     
         14 . The system of  claim 1 , wherein at least one of the optical sensors is configured to sense moisture. 
     
     
         15 . The system of  claim 1 , further comprising one or more optical sensor configured to sense an electrical parameter. 
     
     
         16 . The system of  claim 1 , wherein each optical sensor operates within a different wavelength range and emanates output light in response to input light, the output light having a centroid wavelength that changes in response to the sensed internal parameter of the power transformer. 
     
     
         17 . The system of  claim 1 , wherein the optical coupler spatially disperses light according to wavelength. 
     
     
         18 . The system of  claim 1 , wherein the optical coupler comprises a linear variable filter. 
     
     
         19 . The system of  claim 1 , wherein the optical coupler comprises an arrayed waveguide grating. 
     
     
         20 . The system of  claim 1 , further comprising an optical multiplexer disposed between the optical fibers and the optical coupler. 
     
     
         21 . The system of  claim 20 , wherein the optical multiplexer comprises a time division multiplexer, the time domain multiplexer comprising at least one of:
 a set of M optical switches; and   a single 1×M optical switch.   
     
     
         22 . The system of  claim 21 , wherein the optical multiplexer comprises a wavelength division multiplexer. 
     
     
         23 . The system of  claim 1 , wherein the monitoring system comprises:
 multiple power transformer monitors; and   control circuitry communicatively coupled to each of the power transformer monitors.   
     
     
         24 . The system of  claim 23 , wherein the control circuitry includes the detection units and the detection units are communicatively coupled to each power transformer monitor by an optical communication channel. 
     
     
         25 . The system of  claim 24 , wherein the optical communications channel includes an optical sensor configured to detect intrusion attacks. 
     
     
         26 . The system of  claim 23 , wherein the control circuitry includes an analyzer configured to analyze the electrical signals and to predict, detect and/or diagnose one or more functional, state, and/or degradation conditions of the power transformer based on analysis of the electrical signals. 
     
     
         27 . A monitoring system comprising:
 one or more power grid component monitors for one or more components of a power grid transmission and distribution system, each power grid component monitor comprising a plurality of optical sensors disposed on one or more optical fibers, the optical sensors configured to sense parameters of the power grid component, each optical sensor disposed at a location within or on the power grid component and configured to sense a power grid component parameter that is different from a power grid component parameter sensed by at least one other sensor of the plurality of optical sensors;   one or more detector units, each detector unit configured to convert optical signals of the optical sensors of a corresponding power grid component monitor to electrical signals representative of the sensed power grid component parameters; and   at least one optical coupler disposed between the one or more optical fibers and the detector units, the optical coupler configured to spatially disperse optical signals from the optical sensors according to wavelength.   
     
     
         28 . The system of  claim 27 , further comprising an analyzer configured to analyze the electrical signals and to predict, detect and/or diagnose one or more functional, state, and/or degradation conditions of the power grid components based on analysis of the electrical signals. 
     
     
         29 . A method comprising:
 optically sensing multiple parameters of a power grid component of a power grid transmission and distribution system using multiple optical sensors on an optical fiber disposed within or on the power grid component, at least one of the optical sensors configured to sense a different parameter than other optical sensors;   combining the optical output signals from each sensor into a combined optical signal carried on the optical fiber;   spatially dispersing the combined optical signal according to wavelength; and   generating electrical signals in response to the spatially dispersed optical output signal, the electrical signals representing the sensed parameters of the power grid component.   
     
     
         30 . The method of  claim 29 , further comprising analyzing the electrical signals to predict, detect and/or diagnose one or more of a functional condition, a state, and/or a degradation condition of the power grid component based on analysis of the electrical signals. 
     
     
         31 . The method of  claim 29 , wherein:
 the power grid component is a power grid transformer; and   the optical sensors are configured to sense internal parameters of the power grid transformer, at least one of the optical sensors is configured to sense a different internal parameter than other optical sensors.