A system detects and/or predicts metal ion plating events of a metal ion energy storage device. The system includes an optical sensor disposed internally within or externally on a metal ion energy storage device wherein the optical sensor has an optical output that changes in response to strain within a metal ion energy storage device. A current sensor senses current through the metal ion energy storage device. Plating detection circuitry measures a wavelength shift in the optical output of the optical sensor and estimates a state of charge (SOC) of the metal ion energy storage device based on the current. An expected wavelength shift is determined from the estimated SOC. A plating event can be detected and/or predicted based on the difference between the expected wavelength shift and the measured wavelength shift.

A magneto-optical sensor can be used to measure electrical current with a very narrow pulse width as sensed by the magnetic field in the transmission line region of a pulsed power accelerator. Pulsed power accelerator experimental results agreed remarkably well with the Faraday effect theory, device physical model, and reference electrical current shunt data.

A method for detecting an electrical current longitudinal variation in a power transmission system including a power cable. Electric losses and their location along the cable length can be detected. Current variation in a grounded metallic layer of a power cable is measured from Faraday rotation of polarised light travelling in a single-mode optical fiber wound in a radially external position with respect to the grounded metallic layer. Measurements of the Faraday rotation are carried out by means of polarization-sensitive optical time domain reflectometry (POTDR) or by polarization-sensitive optical frequency domain reflectometry (POFDR) while a direct current is injected in the metallic layer.

Systems and methods detect abnormal conditions in electrical circuits by providing thermal imaging combined with non-contact measurements of current and voltage. Such systems may be implemented in a single test device, or in wired combinations, or in wireless communication implementations with multiple test devices and/or accessories, or in combination with one or more additional devices, such as a mobile phone, tablet, personal computer (PC), cloud-based server, etc. A thermal imaging tool that includes an infrared sensor may first discover and image one or more thermal anomalies in an object, such as an electrical circuit. One or more non-contact current or voltage sensors may be used to measure current and/or voltage, which allows for determination of the power loss at the measured location. The power loss may be used to determine an estimation of the abnormal resistive power losses in a circuit, as well as the costs associated therewith.

Systems and methods detect abnormal conditions in electrical circuits by providing thermal imaging combined with non-contact measurements of current and voltage. Such systems may be implemented in a single test device, or in wired combinations, or in wireless communication implementations with multiple test devices and/or accessories, or in combination with one or more additional devices, such as a mobile phone, tablet, personal computer (PC), cloud-based server, etc. A thermal imaging tool that includes an infrared sensor may first discover and image one or more thermal anomalies in an object, such as an electrical circuit. One or more non-contact current or voltage sensors may be used to measure current and/or voltage, which allows for determination of the power loss at the measured location. The power loss may be used to determine an estimation of the abnormal resistive power losses in a circuit, as well as the costs associated therewith.

A fiber optic sensor system for measuring electric currents, such as the associated with geomagnetic disturbances and electromagnetic pulses. A fiber optic sensor system is disclosed including at least one light source, one or more first optical fibers having a first end arranged to receive light from the light source(s) and transmit the light to at least one of the sensor, and one or more second optical fibers arranged to receive reflected light from the fiber optic sensors and transmit the reflected light to a light sensing element. Using the sensors and the system, it is possible to measure currents within a structure of interest, such as upon the grounded neutral of an electric power transformer, take multiple measurements of current at the same piece of equipment or at multiple locations, or measure current and other physical phenomena on separate materials or structures.

Optical techniques and sensor devices for sensing or measuring electric currents and/or temperature based on photonic sensing techniques in optical reflection modes by using optical dielectric materials exhibiting Faraday effects are provided in various configurations. The disclosed optical sensing technology uses light to carry and transmit the current or temperature information obtained at the sensing location to a remote base station and this optical transmission allows remote sensing in various applications and provide a built-in temperature calibration mechanism to enhance the measurement accuracy in a range of different temperature conditions.

Methods, devices and systems are described that can be used to measure small magnetic fields, such as nano-Tesla and sub nano-Tesla magnetic fields. An example magnetometer includes a core having a photonic material that receives and maintains the propagation of polarized light. The magnetometer's cladding includes a polymer-based magneto-optic (MO) material in contact with the core which surrounds at least part of the core. The core and the cladding are configured to allow at least a portion of the polarized light to enter the cladding to interact with the polymer-based MO material in presence of an external magnetic field. Measurements of the light's polarization state after interaction with the polymer-based magneto-optic (MO) material enable a determination of a strength of the magnetic field.

A fiber-optic current sensor includes an opto-electronics module, a sensor head and a connecting fiber connecting the opto-electronics module to the sensor head. The sensor includes a first and a second beam splitter, between which the measuring light runs in two branches. One fiber connector is arranged in each branch, for connecting a cable assembly to the opto-electronics module. The optical path lengths between the two connectors and the second beam splitter are different, such that light waves cross-coupled into an orthogonal polarization mode due to angular misalignment of the connectors become incoherent with the non-cross-coupled waves returning from the sensor head.

A three-dimensional surface potential distribution measurement apparatus includes: a laser light source; a Pockels crystal; a mirror; a light detector; a support structure which supports the aforementioned elements while maintaining a relative positional relationship therebetween; a movement driver which can move the support structure three-dimensionally; a rotary driver which supports the test object and can rotate the test object about an axis extending in a longitudinal direction of the test object; and a drive controller which controls the movement driver and the rotary driver. The drive controller coordinates a driving operation by the movement driver and by the rotary driver while maintaining a gap between the second end face of the Pockels crystal and a surface of the test object at a predetermined value such that the second end face of the Pockels crystal approaches all the surfaces of the electric field reduction system on the test object.