79 results about "Faraday's law of induction" patented technology

The vibration sensor is composed of magnet and winding. Characters are that when sensor induces external vibration, relative motion between magnetic suspended magnet and magnet fixed inside sensor occurs. Vibration of suspended magnet causes change of flux through coil. Based on Faraday law of electromagnetic induction, coil generates induction electromotive force being direct proportion to vibration velocity. Features are: simple and compact structure without need of metal reed and spring for fixing suspended magnet, wider induced vibration frequency spectrum. The disclosed vibration sensor is new type passive speed type vibration sensor.

The invention designs an alternating magnetic field-resistant manganin current divider, which mainly comprises a manganin resistor and sampling end points of a current divider, wherein a wire is arranged on one side of the current divider; a sampling end point is arranged on both sides of the current divider and is connected with a sampling line; the sampling line on one side is pulled to the other side; and the manganin resistor is divided into two regions of the same area; meanwhile, the sampling line is fixed with the sampling line on the side and the two sampling lines are spirally stranded to extend. In the alternating magnetic field-resistant manganin current divider, the sampling line on the side close to the manganin resistor is pulled to the other side close to the manganin resistor, and the manganin resistor is averagely divided into two regions of the same area, so that induction voltage and electromotive force are produced on the sampling line on the other side close to the manganin resistor according to faraday law of electromagnetic induction when the current divider is interfered by an external alternating magnetic field and are balanced with the induction voltage and the electromotive force produced on the manganin resistor, namely the interference of the alternating magnetic field on the current divider can be prevented.

An electromagnetic and triboelectric hybrid energy collector for low-frequency movement is provided. The electromagnetic and triboelectric hybrid energy collector comprises an electromagnetic module, triboelectric modules and spring mass modules. The electromagnetic module includes a shell, a magnet frame, a magnet array, coil arrays, coil frames and coil magnetic conductive columns. The spring mass modules include respective springs, respective mass blocks and respective end caps. The triboelectric modules include multiple nano-friction power generation units which are connected in sequence. When the energy collector is excited to move a magnet assembly. The electromagnetic module generates voltage according to the Faraday's law of electromagnetic induction. The movement of the magnet assembly generated by external excitation may also cause contact and separation between triboelectric units to generate voltage.

The invention provides a compensating winding system of a power transformer with a single-phase four-column iron core structure. The compensating winding system comprises a left compensating winding and a right compensating winding wound on a left side column and a right side column, and a left compensating winding and a right compensating winding wound on an iron yoke, wherein the outlet end of the left compensating winding wound on the left side column is connected with the outlet end of the left compensating winding wound on the iron yoke, and the outlet end of the right compensating winding wound on the right side column is connected with the outlet end of the right compensating winding wound on the iron yoke. With the adoption of the compensating winding system, according to the Faraday law of electromagnetic induction, a main magnetic flux generated by windings, an additional magnetic flux generated by window-penetrating current and an induction magnetic flux generated by compensating windings can be generated in the iron core, the directions of the induction magnetic flux and the additional magnetic flux are always opposite, and the aim of inhibiting the additional magnetic flux generated by the window-penetrating current is effectively fulfilled.

The invention discloses a method for calculating the transmission torque of a permanent magnet magnetic coupler, and belongs to the technical field of permanent magnet transmission. The method comprises the following steps of firstly, enabling a fan-shaped eddy current region generated on a conductor disc to be equivalent to a circle, and calculating the total eddy current loss power of the conductor disc region according to the Faraday law of electromagnetic induction; and according to a topological structure of the permanent magnet magnetic coupler, establishing a magnetic circuit equivalentmodel containing the main magnetic flux, the leakage magnetic flux, the effective magnetic flux and the induced magnetomotive force; according to the design size of the permanent magnet magnetic coupler, calculating the permanent magnet magnetomotive force, the eddy current area induction magnetomotive force, the main magnetic flux magnetic resistance and the leakage magnetic flux magnetic resistance, and calculating the transmission torque of the permanent magnet coupler, and comparing the transmission torque with the result of a finite element calculation method. The method is a calculationmethod with the engineering practical application value, and is simple and is high in calculation efficiency and low in time cost.

The invention relates to a non-contact multi-point grounding detection method and system for a secondary circuit of a current transformer. A changing magnetic field is exerted on a neutral line in a secondary circuit; on the basis of Faraday's law of electromagnetic induction, whether a current is generated in the neutral line is determined; and only when two-point grounding occurs at the secondary circuit is the current generated in the neutral line. And if only one-point grounding occurs at the loop, no current is generated. The system comprises: a signal injection system, which is used for exerting a changing magnetic field perpendicular to the neutral line in the neutral line; a signal acquisition device, which is used for collecting the current of the neutral line; and a data processing and grounding criterion system, which is used for determining whether multi-point grounding occurs. According to the invention, the method and the system can be applied to a transformation substation for determination of current transformer secondary circuit multi-point grounding examination; and on the premise that normal running of the protection device is ensured to be not influenced, whether multi-point grounding occurs at the secondary circuit of the current transformer can be effectively detected.

The invention discloses an electromagnetic induction comprehensive experiment device capable of obtaining and recording all information of an electromagnetic induction process to be analysed and studied. A cylindrical permanent magnet (1) used by the device passes through a guide tube (3) upright fixed on a special bracket (4) and free falls to a magnet adsorption pad (5) by gravitation; two multi-tap induction coils (2) provided outside the guide tube and capable of moving up and down transmits all changing processes of an induced electromotive force, which is generated when the cylindrical permanent magnet (1) passes, to two passages of a digital storage oscillograph (6) to be displayed and stored. The invention also discloses a manufacturing method of the special bracket and the multi-tap induction coils. The device has a simple structure, is convenient to operate, realizes measurement of physical quantities such as gravity, magnetic force and the like while quantification-studying Faraday's law of electromagnetic and Lenz's law.

The invention belongs to the technical field of railway traffic, and particularly relates to a turnout switch rail point closure deformation device based on electromagnetism eddy excitement collection. The turnout switch rail point closure deformation device based on electromagnetism eddy excitement collection comprises a combined detection coil arranged on a stock rail. The dynamic changes and position states of a turnout switch rail are obtained through the combined detection coil, and multi-group and multi-point real-time data collection is carried out through a high-accuracy excitement collection sensor according to the Faraday law of electromagnetic induction. The turnout switch rail point closure deformation device based on electromagnetism eddy excitement collection further comprises a circuit controller. The circuit controller comprises an excitement circuit module, a transmitting and receiving circuit module, a processing circuit module and a wireless communication circuit module, wherein excitement circuit module is used for providing excitement for the detection coil; the transmitting and receiving circuit module is used for receiving data; the processing circuit module is used for processing signal data; finally, the data are sent to a computer server in a wireless communication mode; data collected by the combined detection coil are transmitted to a circuit control module via a cable. The turnout switch rail point closure deformation device based on electromagnetism eddy excitement collection has the advantages that turnout point closure deformation can be measured in a non-contact mode, accuracy is not affected by temperature changes, and the structure is simple.

The invention provides a thunder and lightning monitoring device of a wind power generator set. The thunder and lightning monitoring device comprises an optical fiber sensor, a thunder and lightning analyzer, a first optical fiber and a second optical fiber; the first optical fiber and the second optical fiber are connected between the optical fiber sensor and the thunder and lightning analyzer; the optical fiber sensor is arranged above an anti-thunder down lead which is arranged on the root portion of a blade; the thunder and lightning analyzer is used for sending first optical signals to the optical fiber sensor through the first optical fiber, receiving returned second optical signals through the second optical fiber and performing analysis on the second optical signals to generate thunder and lightning data. According to the thunder and lightning monitoring device of the wind power generator set, the safe accurate monitoring on the thunder and lightning condition of the wind power generator set can be achieved through the optical signal transmission and the optical measurement based on the Faraday's law of electromagnetic induction.

The invention relates to a rapid detection method and device for invalidation of a parallel single body in a serial-parallel battery pack, which are used for detecting the invalidation of each parallel single body battery. The detection method comprises: winding a spiral coil on the surface of each parallel single body battery in a single direction, and indirectly sampling the size and direction of current in the single body battery by utilizing a Faraday's electromagnetic induction law, so as to judge whether the single body battery is invalid or not based on the size and direction information of the sampled current. The detection method is simple, relatively low in cost budget and relatively high in practicability, and the size and direction of the current in a working process of each single body battery in the parallel battery pack are monitored, so that rapid detection of each single body battery in the parallel battery pack is effectively realized, and the accuracy and reliability of detection are realized; meanwhile, the safety and effectiveness of whole detection, and a battery performance predication capability are improved.

The invention discloses a vibration power generation device comprises a power generation part and a support part, wherein the power generation part comprises a top cover, an upper permanent magnet, a magnetostrictor and a lower permanent magnet which are sequentially laminated and fixed, a coil is wound around the magnetostrictor, and the support part comprises an elastic part and a base. During usage, pressure is applied to the top cover, so that the upper permanent magnet, the magnetostrictor, the coil and the lower permanent magnet downwards move together to cause change of the length of a magnetic path, the coil generates a changing magnetic field, and an induced electromotive force is generated in the coil according to a Faraday law of electromagnetic induction, namely electromagnetic power generation; and when the top cover is pressed, the base is extruded by the lower permanent magnet and is knocked, so that the magnetic path is closed, meanwhile, a generated counter-reacting force acts on the magnetostrictor, the changing magnetic field is generated in the coil according to an inverse magnetostriction effect, and the induced electromotive force is further generated, namely piezomagnetic power generation. The device is simple to design and comprises two power generation processes of electromagnetic power generation and piezomagnetic power generation, and the power generation efficiency is improved.

The invention relates to an analytical model method for the current conversion ratio and the phase difference of an open-type current transformer. The analytical model method comprises the following steps of: (1) establishing the principle model of the open-type current transformer; (2) deriving the magnetic path time-domain equation of the open-type current transformer according to an ohm law for magnetic path, calculating a circuit time-domain equation considering a secondary side load according to a Faraday law of electromagnetic induction and the ohm law, obtaining the actual current conversion ratio and phase difference calculation formulas of the primary side and the secondary side of the open-type current transformer by the magnetic path and circuit time-domain equations, so as to complete an analytical model for the current conversion ratio and the phase difference of the open-type current transformer. The analytical model established by the method disclosed by the invention has an important theoretical direction value on realization for compatibility between the current transformer for measurement and a current transformer for protection, and is capable of providing a theoretical basis for the error compensation of a split core type current transformer used for online calibration for an electric energy meter.

The invention discloses a magnetic dividing sensor used in electromagnetic prospecting, which uses Faradayí»s law of electromagnetic as base and adopts amorphous alloy with high magnetic conductivity as magnetic core. When measuring the frequency or the magnetic field, the output of the magnetic dividing sensor is in direct proportion with the frequency during the frequency range of the detecting signal; when measuring the time or the magnetic field, the output of the magnetic dividing sensor is in independence to the frequency during the frequency range of the detecting signal.

The invention discloses a magnetic core split type magnetic field energy collection device, and belongs to the field of independent environment energy collection design. Based on the Faraday law of electromagnetic induction, the relation between the shape of the magnetic field collecting device and the output power density is determined with the maximum improvement of the output power density as the target in the design process of the independent magnetic field energy collecting device. Secondly, according to magnetic core equivalence analysis, a magnetic field energy collection mode that thecylinder is optimized into a split type in the first step is determined, an effective magnetic conductivity expression is obtained, and the accuracy of the effective magnetic conductivity expression is analyzed; due to the advantage that the new shape is movable after the first step of optimization, the splitting distance of the magnetic field energy collecting device is optimized in the second step, and the two ends of the magnetic core are separated by the same distance to improve output; and finally, the structural stability of the collector is considered to determine that the 80mm split magnetic core is in an optimal shape. In the simulation, the output power is optimized to be 4.05 times of the original output power, and the power density is optimized to be 6.07 times of the originaloutput power.

The invention provides a faraday electromagnetic induction tester, which comprises a solenoid, an induction coil, a magnetic flux density sensor, a voltage sensor, a voltage linear change power supply, a data collector, and a computer. The solenoid is connected with the voltage linear change power supply; the induction coil is arranged outside the solenoid; the magnetic flux density sensor used for measuring the magnetic flux density at the position of the induction coil is arranged in the induction coil; the induction coil is connected with the voltage sensor used for measuring an induced electromotive force; both the magnetic flux density sensor and the voltage sensor are connected with the computer through the data collector; the data collector reads the data collected by the magnetic flux density sensor and the voltage sensor, and transmits the data to the computer. The faraday electromagnetic induction tester has simple structure, can quantitatively research the relationship between the induced electromotive force E and the magnetic flux density change rate Delta B/Delta t and the relationship between the induced electromotive force E and the coil turns n, thus verifying the faraday law of electromagnetic induction.

The invention provides a data acquisition system for a thunder and lightning three-dimensional magnetic field. According to the Faraday's law of electromagnetic induction, an antenna capable of sensing a thunder and lightning magnetic field is designed. According to the characteristics of cloud thunder and lightning magnetic pulses, a signal conditioning circuit and an A/D conversion circuit are designed. Two triggering modules are adopted as the control switch of an acquisition circuit. Finally, the interface of an upper computer is designed by using the Qt. The synchronous collection based on three paths of channels is adopted by the system, so that the peak information, the thunder and lightning occurrence time, the azimuth angle and the magnetic field change waveform of the thunder and lightning three-dimensional magnetic field can be recorded. After that, the recorded information is transmitted to the upper computer through a wireless network. According to the invention, effective data can be provided for the positioning and the early warning of the thunder and the lightning. Meanwhile, important parameters, such as the peak value, the waveform, the rising time and the like of the thunder and lightning current can also be estimated through the data inversion of the acquired three-dimensional magnetic field data. Therefore, the system provides a novel idea for the indirect analysis of thunder and lightning characteristics.

The invention discloses a Faraday law of electromagnetic induction experiment device and an experiment method thereof; the experiment device comprises a teaching variable-frequency power source, a teaching vibration table, a strong magnet, a square coil, and a teaching oscilloscope; the experiment method comprises the following steps: the teaching variable-frequency power source selects a proper AC voltage and frequency to provide power for the teaching vibration table; the strong magnet fixed on a teaching vibration table shaft vibrates up and down; the magnetic flux [phi] in the square coilmakes periodical changes, wherein [delta][phi] is decided by the strong magnet amplitude, and [delta]t is decided by a strong magnet vibration frequency (f=1/T); along with vibration amplitude and frequency changes, an induction electromotive force E=n[delta][phi]/[delta]t also changes; the vibration amplitude of the central bright spot in the oscilloscope can be observed, thus determining the induction electromotive force size and direction, and carrying out quantitative analysis via changing the amplitude and frequency. The Faraday law of electromagnetic induction experiment device and method can solve the Faraday law of electromagnetic induction difficulties and doubtful points in physics teaching, thus fully improving the physics teaching effect.

The invention provides a bicycle self-generating device based on Faraday law of electromagnetic induction. The device includes a magnet arranged on a bicycle front-wheel air nozzle and a canvas bag mounted on the bicycle front fork, a fixedly packaged generating device and an interlayer for receiving an electronic product to be charged are arranged in the canvas bag. When a bicycle moves, the magnet rotating along the wheel periodically changes the magnetic flux of the closed coil in a circuit structure to generate the induction electromotive force in cyclic variation, and the AC induction electromotive force is converted into a DC electromotive force being constant in the electromotive direction and stable in magnitude via the circuit structure to charge the electronic product. The device has the advantages of simple structure, low cost, and convenient detachment and carrying, and after the installation, the beauty of the bicycle is not influenced, and the popularization is facilitated.

The invention discloses a detection method and a device for partial discharge of a mobile transformer, comprising a detection host. The detection host is connected with a high frequency current sensor, a ultrasonic sensor and an ultrahigh frequency sensor. The ultrahigh frequency sensor is arranged at an oil discharge valve of the transformer to detect partial discharge of the transformer, detection frequency band of the ultrahigh frequency sensor is 500 MHz-1500 MHz; the ultrasonic sensor is arranged on surface of a shell of the transformer through adhesive to detect partial discharge of thetransformer, the detection frequency band of the ultrasonic sensor is 20 KHz-100 KHz; a core or clip lead of the transformer passes through center of the high frequency current sensor, according to Faraday's law of electromagnetic induction, varying electric fields generate varying magnetic fields, so that the high frequency current sensor can acquire local discharge signals. According to the detection method and the device for the partial discharge of the mobile transformer, detection technology such as ultrahigh frequency, ultrasonic wave, high frequency current and the like are adopted, thedevice can movably detect on site, detection efficiency of the partial discharge of mobile transformer is obviously improved.

The invention discloses an analysis demonstration instrument for Lenz law and Faraday law of electromagnetic induction. The analysis demonstration instrument comprises a bottom plate (5). A horizontal organic glass tube (10) is installed on the bottom plate. An electromagnetic induction coil (12) with a plurality of taps is fixed outside the tube. A circular magnet box (14) capable of freely sliding is arranged in the tube. Cylindrical magnets of different models are arranged in the box. A direct-current speed regulation motor (13) is arranged on the bottom plate and is placed on the rear side of the organic glass tube. A traction rope (11) is wound onto a motor shaft by one circle and then is connected with the magnet box through four fixed pulleys. One path of the electromagnetic induction coil (12) with the plurality of taps is connected with a measurement binding post, and the other path of the electromagnetic induction coil (12) with the plurality of taps is connected with a set of light emitting diodes which are connected in the anti-parallel manner. A voltage sensor is connected with the plurality of taps of the measurement binding post, and the voltage sensor is connected with a data processing device. According to the analysis demonstration instrument, the Lenz law and the Faraday law of electromagnetic induction can be demonstrated vividly and reliably, and students can easily understand the above laws.