702 results about "Rogowski coil" patented technology

A current transformer includes a Rogowski coil, having an opening at the center in which a conductor penetrates, comprising, a printed circuit board having a plurality of layers forming at least first to fourth circuit board surfaces including a circuit board top surface, a circuit board bottom surface and circuit board conducting internal surfaces between the circuit board top surface and the circuit board bottom surface, a plurality of radial metal foils, each metal foil radiating from a center that is approximately the center of the opening, mounted on the first to fourth circuit board surfaces, a first winding formed by electrically connecting metal foils on the first and second circuit board surfaces with first plated through holes penetrating the first and second circuit board surfaces in a thickness direction of the printed circuit board, a second winding formed by electrically connecting metal foils on the third and fourth circuit board surfaces with second plated through holes penetrating the third and fourth circuit board surfaces in a thickness direction of the printed circuit board, a first return circuit line electrically connected with the first winding in series, a second return circuit line electrically connected with the second winding in series, and a pair of the first winding and the first return circuit line and a pair of the second winding and the second return circuit line being electrically connected in series.

A high-precision Rogowski current transformer, the Rogowski coil is realized in a single printed circuit board while maintaining both the outside field rejection of a traditional Rogowski coil, and the increased output voltage similar to the multiple printed circuit board Rogowski coil arrangements.

An exemplary camera module includes a lens mount, a lens unit, a magnet unit, a printed circuit board (PCB)-based Rogowski coil and a blade spring. The PCB-based Rogowski coil is fixed around the lens unit. The PCB-based Rogowski coil establishes an induced magnetic field when an electric current is applied thereto. The induced magnetic field interacts with the magnet unit to generate a magnetic force moving the lens unit telescopically. The blade spring includes a plurality of ribs. Each rib includes a moveable end connected with the lens unit and an opposite fixed end. The moveable end moves together with the lens unit with respect to the fixed end to cause the ribs to distort and generate an elastic force. The lens unit stops at a focal position when the magnetic force and the elastic force come to a balance.

The invention discloses a fault positioning method for a transmission line and belongs to the technical field of power systems. The fault positioning method comprises the following steps: arranging a Rogowski coil-based broadband core-through traveling wave detection device on the high-voltage transmission line; acquiring a current traveling wave signal of a three-phase line; performing singular value detection by applying the phase mode conversion and wavelet mode maximum principle; accurately identifying the traveling wave line mode wave head, and accurately determining the wave head arrival time by using a GPS high-precision clock; and measuring the wave speed of real-time traveling wave mode on line according to different wave head time difference information to realize accurate fault positioning. The fault positioning method has the advantages of effectively avoiding two main factors influencing the traveling wave fault positioning precision, along with high positioning precision and accurate and reliable fault positioning result.

An improved Rogowski coil is formed on a toroidal core made of a thermoplastic or other moldable material, the core having a preferably continuous groove or grooves extending around the core. The grooves correspond in size to magnet wire which registers within the grooves, thus controlling the specific location of the wires. The grooving may be helical. A return loop can be provided for return path cancellation, or a reverse winding can be added in a direction opposite to the direction of advancement of the main coil. In using the return loop, a resistive network can be added to improve the cancellation of the return path due to the effect of geometries. In addition, it can compensate for thermal and other variations.

A precision printed circuit board based Rogowski coil is formed including a printed circuit board including a first layer and second layer. The printed circuit board further defines an aperture for receiving an electrical path therethough. A first return path is defined about the aperture on the first layer of the printed circuit board, and a second return path—parallel to the first return path—is defined about the aperture on the second layer of the printed circuit board. A plurality of radial paths defined on the first layer of printed circuit board extend between the aperture and the first return path. A plurality of radial paths defined on the second layer of the printed circuit board extend between the aperture and the second return path. Each first layer radial path is connected with an adjacent second layer radial path to form a generally toroidally-shaped winding.

A Rogowski coil includes a core, a Rogowski coil winding disposed on the core, an insulator disposed on the Rogowski coil winding disposed on the core, and a conductive winding disposed on the insulator disposed on the Rogowski coil winding disposed on the core. The conductive winding includes an electrical connection structured to be grounded. When the conductive winding is grounded, the grounded conductive winding provides electrostatic shielding for the Rogowski coil winding of the Rogowski coil.

Current testing/measuring apparatus 10 comprises a flexible member 12 having a first end 14 and a second end 16. In use, the flexible member 12 is arranged to locate around a conductor 11 carrying a current to be measured. In particular, the current measuring apparatus 10 comprises a Rogowski coil. The ends of the flexible member 12 are coupled together in use but a gap is created between the ends. This distance can generate errors in the current measurement and the present invention provides compensation means 28 in the form of a compensation windings. The compensation windings comprise a planar spiral conductor provided on a printed circuit board to compensate for the separation distance between the first end and the second end.

A current sensor is disclosed. The current sensor includes a Rogowski coil disposed on a flexible printed circuit board with at least one active lead passing through the Rogowski coil.

The invention discloses a kind of current sensor, the character lies in: the feedback windings in the two symmetrical channels are connected in series, one end is accessed to the ground, the other end is accessed to one end of the sample resistance; the output of the symmetrical Hall elements are amplified, then carries on filter, voltage-current transform, current amplifying process, the output end is accessed to another end of the sample resistance, the detected voltage signal detected at two ends of the sample resistance; it also includes Rogowski coil, the two ends of the coil are connected in parallel to the sample resistance, the detected voltage signal of sample resistance is amplified, filtered and integral amplified, and transmitted to the computer; the computer process the data and transmits the detected current to the monitor to be displayed; the precision is higher than 0.5%. The power consumption is small, the temperature additional error is less than 0.1%/10 degrees centigrade, the structure is simple, and easy to be assembled, debugged and maintained.

A differential protection system for power transformers using Rogowski coils as current sensors can support an inrush current detection method based on sensing lows in the derivative of the sensed current. Effective detection of power transformer inrush conditions can enable blocking of a protection relay during inrush where the differential current may exceed a differential threshold value indicative of a fault without the presence of an actual fault. The outputs of the Rogowski coils, being proportional to the first time derivative of the sensed current, may be useful in the inrush detection method. Also, with reduced saturation concerns, the Rogowski coil protection system may employ a single slope response with increased sensitivity. A discrete time sampling technique for identifying low di/dt portions within the sensed current also may be useful in detecting power transformer inrush conditions.

An electrical switching apparatus includes a plurality of poles each having a Rogowski coil and a conductor passing through an opening thereof, and a processor circuit including a sensor circuit including a plurality of inputs each electrically interconnected with an output of the Rogowski coil of a corresponding pole. The sensor circuit further includes a number of outputs having values each corresponding to current flowing through the conductor, a memory including for each corresponding pole an offset value and a gain correction factor for the sensor circuit, and a gain correction factor for the Rogowski coil, a number of routines, and a processor cooperating with the sensor circuit and the routines to provide for each pole a corrected current value as a function of a corresponding one of the values, the sensor circuit offset value and gain correction factor, and the Rogowski coil gain correction factor.

The present disclosure describes a system for measuring current amplitude in a conductor, comprising at least one Rogowski coil, an integration circuit directly connected to the at least one Rogowski coil, a microprocessor circuit in communication with the integration circuit and configured to receive output from the integration circuit and to calculate energy data comprising current amplitude in the conductor. A method for measuring current in a conductor is also presented.

The invention relates to a current sensor for the polluted insulator leakage of an AC high-voltage electric transmission line, in particular to a current sensor for monitoring pollution flashover of an electric transmission line. The current sensor mainly comprises a Rogowski coil with an iron core, a copper shielding shell and a coaxial cable joint and is characterized in that the iron core of the Rogowski coil is in a two semi-circle ring shape and is provided with two windings; and the shielding shell consists of a hollow groove in the two semi-circle ring shape and an upper cover in the two semi-circle ring shape. The invention has the advantages of simple assembling and disassembling process, very convenient field assembly and disassembly, high leakage current measuring precision, wide frequency band, good linearity, safe and reliable operation, and the like, thereby being widely used for newly-established and operated high-voltage electric transmission lines.

The invention discloses an online fault monitoring device for a cable connector in a 10-35kV power distribution network. The online fault monitoring device comprises two current sensors, a difference module, an A/D convertor, a lower computer and a power supply module, wherein the two current sensors are mounted at the two ends of the cable connector in the 10-35 kV power distribution network; pulse current signals received by the current sensors are processed by the difference module to obtain induced voltage signals at the two ends of the cable connector, the induced voltage signals are converted into digital signals through the A/D convertor, and the digital signals are processed by the lower computer to obtain the insulation condition data of the cable connector. The invention further discloses a method for evaluating the system state of the online fault monitoring device for the cable connector in the 10-35kV power distribution network. The method adopts two rogowski coils for high-frequency electromagnetic coupling to respectively collect partial discharge pulse signals, so that the possibility of difference processing on the partial discharge signals of the cable connector is provided. After the signals are subjected to the difference processing, the partial discharge pulse signals can be amplified without distortion, interference signals from the outside can be effectively shielded, and the field interference is effectively restrained.

The current measurement apparatus comprises a Rogowski coil 20 comprising a wire or conductor which forms a coil 22 and returns through the coil 22 as a central conductor. The coil 22 and the central conductor are formed from a single conductor or wire and, therefore, no electrical join (for example, a solder join or crimp) is required at the end of the Rogowski coil. The wire 28 used to form the coil 22 and the central conductor 24 is insulated prior to forming the Rogowski coil. The insulated coating 30 provides better insulation between individual coils and also helps to provide a more even spacing between the coils.

The invention discloses a short-time slowly-varying high-current measuring device based on a (printed circuit board) PCB type Rogowski coil, and the short-time slowly-varying high-current measuring device comprises the PCB type Rogowski coil, a sampling resistor and signal receiving equipment, wherein an inertialess link integrating circuit and a variable interval (VI) switching circuit are additionally and successively arranged between the PCB type Rogowski coil and the sampling resistor; and the PCB type Rogowski coil is a PCB type Rogowski coil which is provided with symmetrically arranged wires on two faces and is provided with return wires. The short time slowly-varying high-current measuring device has the advantages that direct currents or low frequency high currents can be detected, the measuring bandwidth of the short time slowly-varying high-current measuring device can reach up to DC swung dash 200kHz, and the deficiencies of a conventional current sensor on the aspect of measurement of the direct currents or the low frequency high currents are eliminated; and since the PCB type Rogowski coil which is provided with the symmetrically arranged wires and is provided with the return wires is adopted by the short time slowly-varying high-current measuring device as a sensing head, complex electromagnetic interferences in a high-current system can be effectively eliminated, and a full-analog signal transmission manner is adopted by the device, so measurement errors can be effectively reduced.

Rogowski coil assemblies and methods for providing or forming Rogowski coil assemblies are provided. A Rogowski coil assembly may include a printed circuit board and a plurality of Rogowski coil sections mounted to an external surface of the printed circuit board by one or more respective circuit traces. The circuit traces may retain and connect the plurality of Rogowski coil sections.