174 results about "Eddy current effect" patented technology

The invention relates to the technical field of rotor unmanned aerial vehicle motors, in particular to an integrated motor for a rotor unmanned aerial vehicle in a dual-control mode. Comprising a motor stator which comprises a stator core, a stator winding and a stator seat, and the stator seat is fixedly connected to a driver shell; the motor rotor comprises a rotor iron core, rotor magnetic steel, a rotor shell and a penetrating type rotor through shaft, and the rotor through shaft is rotationally connected with the stator seat through a rotor bearing. Through topological innovation of the rotor through shaft integrated self-cooling fan, the rotating speed of the fan is automatically matched with the running state of the motor, and the active suppression of the junction temperature of a power device is realized by using the forced eddy current effect in the driver shell.

The invention provides an oil aliasing particle detection device based on a multi-frequency eddy current effect, which adopts a multi-mode electromagnetic sensing architecture, integrates three groups of orthogonally arranged solenoid coil detection units in a single detection channel, and respectively loads low-frequency (10-100kHz), intermediate-frequency (100kHz-1MHz) and high-frequency (1-10MHz) excitation signals with different characteristics, so as to detect the aliasing particles in the oil. Based on frequency domain response characteristic differences presented by different metal particles in high, medium and low frequency eddy current fields, a particle material-size-space distribution frequency domain characteristic matrix is constructed through multi-physics field coupling modeling, and synchronous identification and orthogonal decoupling of ferromagnetic particles and non-ferromagnetic particles are realized. According to the invention, the eddy current effect difference characteristics of metal / non-metal particles under excitation of different frequencies are utilized, and a signal decoupling algorithm is combined to realize accurate distinguishing of aliasing particles, so that the reliability of high-flux oil detection is remarkably improved; and a key technical support is provided for engineering application of a microfluid chip technology in the fields of engine wear monitoring, hydraulic system fault early warning and the like.

The invention relates to the technical field of electromechanical hydraulic systems, and particularly discloses a low-temperature cold start control method based on high-frequency injection, which comprises the following steps: analyzing a motor state, and carrying out observation and feed-forward compensation on disturbance caused by the motor state to a load torque and a viscosity coefficient through a sliding mode observer algorithm; according to the motor state, obtaining a state equation, constructing an extended sliding mode observer equation, deriving to obtain an observer error equation, and observing the load torque; analyzing the obtained load torque, wherein the motor load torque reflects the oil viscosity; high-frequency current injection, injection frequency control, skin effect enhancement and current amplitude control are carried out in a low-temperature state according to an oil viscosity result, copper loss and a high-frequency magnetic field eddy current effect are used for assisting heat generation, and according to a final oil viscosity result, when electromagnetic heat generation viscosity is reduced and a load is reduced, an injection voltage amplitude is gradually reduced. And after a normal starting condition is reached, switching to normal id = 0 control.

The invention discloses a planar two-dimensional micro-displacement sensor based on a four-quadrant eddy current effect, which comprises a detection coil array plate and a target conductor array plate which are parallel up and down, and is characterized in that the detection coil array plate is provided with four planar coils arranged in a shape like a Chinese character'tian 'on an insulating substrate; the target conductor array plate is provided with four metal panels which are arranged in a shape like a Chinese character'tian 'on an insulating substrate. According to the invention, identical excitation signals are introduced into four planar coils on a detection coil array plate, two-dimensional micro-displacement of the detection coil array plate relative to a target conductor array plate is converted into voltage signals of the four planar coils by using an inductance measurement circuit, and the four voltage signals are processed by using a microprocessor system; therefore, the two-dimensional plane relative displacement of the detection coil array plate and the target conductor array plate is obtained. The device is simple in structure, high in measurement precision and suitable for scenes requiring precise measurement of planar two-dimensional micro-displacement in severe environments such as dust and greasy dirt.

The embodiment of the invention discloses a lubricating grease heating device of a wind driven generator and a control method of the lubricating grease heating device, lubricating grease is located in a shell, and the lubricating grease heating device of the wind driven generator comprises a mounting disc, a heating coil, a circuit board, a temperature sensor and a control device. The installation disc is connected with the outer wall of the shell, the heating coil is connected with the installation disc, a heating circuit is arranged on the circuit board and connected with the heating coil, the heating coil is used for generating a variable magnetic field to enable the shell to generate an eddy current effect, and the temperature sensor is located in the shell and used for obtaining the temperature value of lubricating grease. And the control device is connected with the temperature sensor and is used for controlling the on-off of the heating circuit according to the temperature value. The control device controls the on-off of the heating circuit according to the temperature value and further controls the heating state of the lubricating grease, so that the temperature of the lubricating grease is kept within an ideal range, the lubricating effect of the lubricating grease is guaranteed, and the lubricating grease is prevented from being solidified and hardened due to low temperature.

The invention relates to the technical field of electromagnetic measurement, and discloses a measurement unit stabilization method and system, electronic equipment and a storage medium, and the method comprises the steps: obtaining three-dimensional displacement trajectory data in real time, and building a motion error compensation model containing a mechanical vibration direction vector and a phase offset; on the basis of asymmetric magnetic pole distribution, combined with phase difference calculation of a magnetic circuit gradient direction vector and a mechanical vibration direction vector, a closed loop current orthogonal to the mechanical vibration direction vector is generated on an interface to realize gradient isolation; based on a multi-branch common-mode suppression mechanism, an interference signal reaches a preset attenuation amplitude before a loop is closed through combination of a magnetic core impedance matching characteristic and an eddy current effect; and performing dynamic matching based on the displacement parameter and an electromagnetic interference attenuation result, adjusting a magnetic pole inclination angle in real time, and forming a closed-loop control path of magnetic field gradient compensation and mechanical vibration suppression. According to the invention, the stability and anti-interference capability of the measuring unit under severe working conditions can be improved.

The invention discloses an electric leakage detection method of an explosion-proof distribution box, particularly relates to the technical field of electric power safety in flammable and explosive environments, and is used for solving the problems of electric leakage signal attenuation and insufficient detection sensitivity caused by an eddy current effect of a metal explosion-proof shell. An original electric leakage signal of a wire in a box is obtained, and an eddy current compensation factor is constructed based on the material and thickness of a shell to carry out gain compensation; shell surface temperature distribution and three-dimensional magnetic field components are synchronously collected, and a compensation failure state is judged through collaborative analysis of high-temperature area migration acceleration and magnetic field polarization angle offset; when the compensation is effective, the area score of the space magnetic field rotation on the surface of the shell is calculated, and when the time change gradient exceeds a preset threshold value, the tripping action is triggered, the shielding effect of shell eddy current on weak electric leakage signals is broken through, and high-sensitivity electric leakage protection is realized while the explosion-proof integrity is maintained.

The invention relates to the technical field of foamed aluminum detection, and discloses a foamed aluminum insulation detection method based on an eddy current effect. The method comprises the following steps: dividing a foamed aluminum sample to be detected into a plurality of detection units, and collecting eddy current signal data, material structure data and environmental parameter data of each unit to form a multi-source detection data set; then, an insulation defect evaluation index and a material stability evaluation index are constructed according to the multi-source detection data set, and an initial defect value is generated through a preset threshold mechanism; and dynamically correcting the initial defect value based on the material relevance of the adjacent detection units to obtain a corrected defect value. And finally, generating a priority list according to the corrected defect value sequence, and outputting an insulation performance evaluation result in combination with a visual tool. According to the method, comprehensive and accurate detection of the insulation performance of the foamed aluminum is realized, a systematic and effective technical scheme is provided for identification and evaluation of insulation defects of the foamed aluminum, and the method is suitable for insulation performance detection scenes in the production and application process of the foamed aluminum.

The invention discloses a paper folding structure inductance type self-decoupling miniature six-dimensional force sensor, which belongs to the technical field of force sensors and comprises a base, a folding flexible circuit board, a metal shell, a communication cable, a coil inductance measuring circuit and an elastic body. The folding flexible circuit board comprises a coil array and an inductance measuring circuit, the coil array is folded on the upper surface and the four side faces of the base, the inductance measuring circuit is folded at the bottom of the base, and a communication cable is led out of the inductance measuring circuit. The metal shell is arranged above the base and surrounds the surface, except the bottom surface, of the folding flexible circuit board; an elastic body is arranged between the metal shell and the base. The elastomer converts six-dimensional force borne by the metal shell into six-dimensional displacement. According to the sensor, the characteristic that the eddy current effect is sensitive to normal displacement and insensitive to tangential displacement and rotation is utilized, self-decoupling measurement of six-dimensional displacement of the metal shell is achieved in combination with three-dimensional coil layout, and therefore self-decoupling six-dimensional force measurement is achieved, and the sensor can be integrated to the fingertip of the dexterous hand to provide endogenous tactile perception.

The invention relates to the technical field of electric energy metering, in particular to a high-precision voltage and current synchronous metering system of an alternating current and direct current integrated standard electric energy meter, which is characterized in that a hysteresis analysis module and an eddy current analysis module are used for respectively analyzing current signals to obtain a hysteresis intensity factor and an eddy current loss factor of the electric energy meter; a time scale weight and an instantaneous energy loss proportion are introduced through a hysteresis and eddy current coupling module, a comprehensive loss factor of an eddy current effect and a hysteresis effect is analyzed, self-adaptive distribution of weights of the eddy current effect and the hysteresis effect is realized, and primary compensation is performed on a current signal; the temperature compensation module analyzes the influence of the temperature on the electric energy meter, and performs temperature compensation on the voltage signal and the current signal. The system can effectively cope with complex dynamic working conditions, guarantees the temperature stability of measurement, cuts off the transmission and accumulation paths of errors from the source, improves the metering precision under AC / DC mixed signals, and guarantees the interpretability and reliability of the system.

The invention discloses a contact type micro-nano probe with a high dynamic response characteristic, which is characterized in that an optical measuring unit is arranged in a measuring cylinder, and a measuring head unit is arranged below the measuring cylinder; an elastic mechanism is arranged between the two circular ring seats in the measuring head unit, a suspension sheet is arranged in the center area of the elastic mechanism, one side of the suspension sheet faces a plane mirror in the measuring cylinder, a probe is installed on the other side of the suspension sheet, the elastic mechanism is a magnetizer, and permanent magnets are arranged on the two sides of the magnetizer respectively; for vibration transmitted to the elastic mechanism in the working process of the probe, the elastic mechanism and the permanent magnets on the two sides form a damping unit through the eddy current effect, the damping effect is generated, the elastic mechanism tends to be stable more quickly after the probe is triggered, and the high dynamic response characteristic of the probe is obtained.

The invention belongs to the technical field of magnetic suspension, and discloses an axial magnetic suspension bearing system modeling and controller design method based on different-element fractional order, which comprises the following steps of: 1, deducing a fractional order axial magnetic suspension rotor mathematical model which considers an eddy current effect and has four denominators through a Maxwell differential equation set; 2, designing a fractional order expansion state observer according to the mathematical model so as to obtain accurate state estimation and system disturbance; and step 3, designing a fractional order sliding mode controller based on the mathematical model of known disturbance. According to the method, the axial fractional order magnetic suspension bearing with four denominators is established by adopting a method based on Maxwell's equations, the adaptive capacity of a system to parameter change and uncertainty is enhanced by combining a fractional order sliding mode control strategy (FSMC) of a fractional order extended state observer (FESO), and it is ensured that the system can still work normally even under extreme working conditions. And the system can maintain good dynamic response and stability.

The invention discloses an alternating current ice melting optimization processing method and system for ice melting of a power transmission line. The method comprises the following steps: predicting ice layer thickness distribution data based on obtained surface temperature distribution data and environment data of a target line; calculating heat demand data according to the ice layer thickness distribution data and the efficiency data of the alternating current ice melting equipment; calculating current configuration data and frequency configuration data of the AC deicing equipment according to the heat demand data, and inputting the current configuration data and the frequency configuration data into a pre-constructed eddy current effect prediction model to obtain eddy current distribution data of the target line; performing judgment based on electromagnetic shielding effectiveness data obtained by quantifying the eddy current distribution data, and if the electromagnetic shielding effectiveness data is lower than a preset threshold value, inputting the eddy current distribution data and the heat demand data into a three-dimensional parameter space optimization model for solving to obtain a current distribution scheme; and executing a control instruction generated by the current distribution scheme. According to the method, stable operation of the power transmission line is realized.

This disclosure provides an X-ray imaging device and a wireless power transmission device with electromagnetic shielding. The wireless power transmission device includes: a first annular structure, on which a first frame is fixed, and a first winding is wound; a second annular structure, on which a second frame is fixed, and a second winding is wound; wherein the second annular structure is rotatable relative to the first annular structure; and a metal shielding assembly disposed relative to the first winding and / or the second winding, the metal shielding assembly being used to generate a reverse magnetic field based on the eddy current effect to weaken the main magnetic flux of the wireless power transmission device. This disclosure utilizes the reverse magnetic field generated by the metal shielding assembly based on the eddy current effect to weaken the main magnetic flux of the wireless power transmission device, thereby reducing magnetic field leakage and thus reducing electromagnetic interference of the wireless power transmission device.

The application relates to an axial-radial hybrid excitation magnetic bearing with a compensation winding, characterized in that the axial-radial hybrid excitation magnetic bearing comprises a rotor, an axial stator, a sleeve, a radial stator, a radial stator magnetic yoke, an axial control winding, a radial control winding, a permanent magnet ring and a compensation winding; the radial stator is arranged on the outer circumferential side of the rotor and comprises a plurality of radial stator iron core magnetic poles uniformly distributed in the circumferential direction and having the radial control winding wound thereon; two axial stators are symmetrically arranged on the upper and lower sides of the circumferential part of the rotor and the radial stator and the outer circumferential parts of the two axial stators are connected with the sleeve; the radial stator magnetic yoke is arranged on the outer circumferential side of the radial stator, and two permanent magnet rings are respectively arranged between the two axial stators and the radial stator magnetic yoke; the axial control winding is wound between the sleeve and the radial stator magnetic yoke; and two compensation windings are respectively arranged between the axial stators and the permanent magnet rings. The axial-radial hybrid excitation magnetic bearing has the advantages of compact axial and radial design, low power consumption, small volume, adjustable rigidity, inhibition of axial eddy current effect and high stability.

The present application relates to a kind of permanent magnet shielding motor vector control energy efficiency optimization method considering magnetic field lagging phase angle, belong to permanent magnet shielding motor control field.It is characterized by: by analyzing shield sleeve eddy current effect, the analytical expression of magnetic field lagging phase angle is derived using electromagnetic field theory;The lagging phase angle is introduced into permanent magnet flux linkage term to be corrected, and the eddy current loss of shield sleeve and stator iron loss are combined into equivalent iron loss component, and a system controllable loss model is constructed;Under the constraint of constant torque, the analytical expression of total controllable loss about direct-axis current is derived and the optimal direct-axis current given value is solved.The actual application introduces angle compensation in the coordinate transformation link of vector control system, and the optimal direct-axis current given value is sent into current regulator, the accurate decoupling of dq axis current is realized, the total loss of motor is reduced, so as to improve the overall efficiency of motor control system.

The invention relates to the technical field of nuclear facility pipeline heating. The invention provides a pipeline heating device and an in-reactor test facility. The pipeline heating device comprises a magnetic conduction layer, a heat conduction layer, a heat preservation layer and an electromagnetic induction coil, the magnetic conduction layer is made of a magnetic alloy material, and the magnetic conduction layer is enclosed and internally forms a heating area used for containing a pipeline; the heat conduction layer is located on the side, facing the heating area, of the magnetic conduction layer and used for transmitting heat of the magnetic conduction layer to the pipeline. The heat preservation layer wraps the side, away from the heating area, of the magnetic conduction layer. The electromagnetic induction coil is wound around the side, away from the heating area, of the heat preservation layer. The magnetic conductive layer made of the magnetic alloy material serves as a main absorption and conversion carrier of magnetic field energy, the eddy current effect can be remarkably enhanced, the problem that the heating efficiency is insufficient due to low magnetic conductivity of the austenitic stainless steel pipeline is solved, and the heating efficiency is greatly improved. The arrangement of the magnetic conductive layer can fundamentally avoid material microscopic damage caused by direct action of a magnetic field, and the safety is higher.

This invention discloses an R-T-B sintered magnet with reduced eddy current losses, its preparation method, and its application. The magnet has partition grooves on one or two orientation surfaces, where each orientation surface is perpendicular to the orientation direction of the magnet. The partition grooves extend through the magnet in a first extension direction but not in a second extension direction. The first extension direction of the partition grooves is perpendicular to the orientation direction of the magnet, and the second extension direction is parallel to the orientation direction of the magnet. By creating crisscrossing partition grooves on the magnet and filling them with an insulating layer, this invention increases the resistivity of a thin layer on the magnet's surface by a certain thickness, significantly reducing motor power loss due to eddy current effects. The insulating layer filling the grooves increases the resistivity of both the magnet surface and the grooves, effectively preventing conduction due to poor processing or current breakdown when the groove width is narrow. It also compensates for the reduction in mechanical strength caused by the grooving, ultimately resulting in a low-eddy-current, high-strength sintered magnet.

The invention provides a foreign matter detection system and method for an electric vehicle wireless charging system, and belongs to the technical field of electric vehicle wireless charging, and the foreign matter detection system comprises a double-comb-shaped self-resonance detection coil module, a high-frequency signal excitation module, a signal processing and detection module and a main control and discrimination module. The foreign matter detection method comprises the following steps: S1, calibrating initial parameters of a system and establishing a reference; and S2, real-time monitoring and foreign matter discrimination. According to the invention, the double-comb-shaped self-resonance detection coil module is designed, so that the adverse effect of an eddy current effect on a detection system is effectively eliminated in principle, noise in a detection signal is remarkably reduced, complete decoupling with a power magnetic field is realized, mutual independence of foreign matter detection and wireless energy transmission is ensured, a detection blind area is avoided, and the detection accuracy is improved. And a detection method based on orthogonal demodulation is introduced, so that the detection accuracy is improved.

The invention relates to the technical field of pipeline filters, in particular to a vertical pipeline filter which comprises a vertical mounting pipe and a transverse mounting pipe, the transverse mounting pipe is communicated with the vertical mounting pipe, a mounting disc and a partition disc are sequentially arranged in the vertical mounting pipe from bottom to top, and a closed cavity is formed between the mounting disc and the partition disc. A filtering and adsorbing assembly is arranged in the vertical mounting pipe and is of a conical structure, a plurality of flow guide pipes are circumferentially distributed at the narrower bottom of the filtering and adsorbing assembly around the conical inclined surface of the filtering and adsorbing assembly, a vortex structure is formed by the flow guide pipes, and the flow guide pipes are communicated with the transverse mounting pipe through a closed cavity; an eddy current assembly is arranged at the top end in the filtering and adsorbing assembly and comprises a wind shield of a conical structure, a plurality of rotating assemblies are sequentially arranged at the narrow bottom of the wind shield from bottom to top, and the rotating assemblies are sequentially enlarged from bottom to top and used for improving the eddy current effect.

The utility model relates to the technical field of anti-vibration, and discloses a high-damping anti-vibration seat of integrated circuit equipment, which comprises an anti-vibration seat and a base. According to the high-damping anti-vibration seat of the integrated circuit equipment, through the arrangement of the supporting seat, the base, the damping mechanism and the elastic mechanism, when the integrated circuit equipment is vibrated, the acting force borne by the supporting seat can be transmitted to the piston rod, the piston rod is forced to vibrate, and magnetorheological fluid is pushed to flow in the annular cavity; a magnetic field generated by the permanent magnet array enables magnetorheological fluid particles to form a chain-shaped structure, fluid shear stress is greatly increased, nonlinear viscous resistance is generated, meanwhile, vertical reciprocating motion of the piston rod cuts magnetic induction lines of the permanent magnet array, an eddy current effect is triggered, reverse electromagnetic damping force is generated, and the damping effect is improved. Therefore, magnetic circuit cutting and fluid extrusion are achieved while movement of the piston rod is achieved, a composite energy dissipation mechanism of electromagnetic damping and viscous damping is formed, and the energy dissipation efficiency and the resonance peak suppression efficiency are remarkably improved.

The utility model provides a heating plate, an electromagnetic heating device and a composite device, and relates to the technical field of battery manufacturing. The heating plate comprises a heating piece, an electromagnetic coil, a sensor and a controller. The heating piece is provided with a first mounting hole and a second mounting hole; the electromagnetic coil is arranged in the first mounting hole; the sensor is arranged in the second mounting hole; and the controller is simultaneously connected with the electromagnetic coil and the sensor. The electromagnetic coil is electrified through the controller to generate a magnetic field, magnetic lines of the generated magnetic field can generate an eddy current effect in the surface of the heating piece when passing through the surface of the heating piece, a large amount of heat energy can be generated due to the inherent resistance effect of the heating piece, the surface of the heating piece can be automatically and rapidly heated, and heating is more uniform; the sensor is arranged in the second mounting hole of the heating piece to detect the temperature of the heating piece in real time, the controller receives the temperature obtained by the sensor, the surface temperature of the heating piece is accurately controlled, and the heating efficiency and the heating quality are effectively improved.

The utility model relates to an electromagnetic heating temperature control drying machine, and relates to the field of powder stirring, drying and mixing. A multi-piece stirring paddle is arranged in a container barrel body, a magnetic guide sleeve is arranged on the periphery of the container barrel body, an electromagnetic heating coil is wound on one side, far away from the container barrel body, of the magnetic guide sleeve, a temperature sensor is further arranged, and the temperature sensor is fixed to the magnetic guide sleeve and the container barrel body through a mounting base and used for monitoring the temperature of materials in the container barrel body; wherein a water channel is arranged between the container barrel body and the magnetic guide sleeve, circulating water flows in the water channel, and the electromagnetic heating coil and the temperature sensor are both electrically connected with the control box. Under the condition, the electromagnetic heating is long in service life, safe and reliable, the electromagnetic heating coil does not generate heat, and the maintenance cost is extremely low; moreover, the mode is efficient, energy-saving and accurate in temperature control, an internal heating mode is adopted, internal components in the heating body generate heat due to electromagnetic induction and an eddy current effect, the hot start is very fast, and the product drying effect is good.

The invention discloses a non-contact iron object positioning detection and marking system, which is particularly suitable for a building template embedded nut positioning scene. The system transmits an alternating magnetic field through the electromagnetic induction module to penetrate through a non-metal obstacle (such as a wood board), detects an eddy current effect generated by an iron object (such as a pre-embedded nut) and outputs a 0-10V voltage signal; the central processing unit locks the geometric center position of the object according to the minimum voltage value, and realizes multi-mode feedback through visual color circle zooming, buzzing frequency change and threshold alarm; and after the user triggers the marking key, the execution module automatically performs annular mark marking at the position of the central point. According to the scheme, the problems of penetrability accurate positioning and automatic marking of hidden iron objects are solved, and the construction efficiency and safety are remarkably improved.

The invention provides an amorphous nanocrystalline sheet and a preparation method thereof. The preparation method of the amorphous nanocrystalline sheet comprises the following steps: winding an amorphous nanocrystalline ribbon into an amorphous nanocrystalline ring; pressing the amorphous nanocrystalline ring into a plane structure; the plane structure is placed in a mold and fixed, and then magnetic field annealing treatment and gum dipping treatment are conducted on the plane structure; performing glue layer curing treatment on the plane structure subjected to magnetic field annealing treatment and glue dipping treatment; and removing the mold, and cutting the plane structure after the glue layer is cured, so as to form the amorphous nanocrystalline sheet with internal layering. According to the preparation method of the amorphous nanocrystalline sheet, the interlayer eddy current effect is effectively reduced, the flatness and high magnetic conductivity of the amorphous nanocrystalline sheet are ensured, and the amorphous nanocrystalline sheet can be conveniently applied to various power electronic magnetic elements.

The present invention relates to a measuring device for measuring the diameter and depth of micro-holes by using the eddy current effect, belonging to the technical field of eddy current measurement. It includes a sliding table mechanism and a measuring mechanism; the sliding table mechanism includes a stepping motor, a ball screw and a sliding table; the output shaft of the stepping motor is connected to the input end of the ball screw; the sliding table is threadedly engaged on the ball screw to achieve position adjustment along the ball screw; the measuring mechanism includes a probe holder and an eddy current measuring probe; the eddy current measuring probe is fixedly arranged on the probe holder, and the detection part corresponds to the sliding table below. During measurement, the workpiece to be measured is fixed on the sliding table, and the sliding table driven by the stepping motor moves slowly and uniformly on the ball screw. The micro-holes on the workpiece to be measured affect the eddy current effect between the workpiece to be measured and the measuring coil on the eddy current measuring probe, resulting in a change in the inductance value of the measuring coil. By the characteristics of the change in the inductance value of the measuring coil, the measurement of the diameter and depth of the micro-holes on the workpiece to be measured is realized.

The application provides a metal film thickness measurement method and device for tungsten gate chemical mechanical polishing, comprising a sensor probe, a power module, a signal excitation module, a differential amplification module, a synchronous demodulation module, a data acquisition and processing module; the sensor probe comprises coaxially arranged excitation coils, detection coils and balance coils; the signal excitation module drives the three-coil resonance module to induce eddy current effect at the metal film to be measured; the differential amplification module converts the equivalent impedance change caused by the eddy current effect in the coils into a differential signal, and simultaneously improves the dynamic range through low-noise amplification; subsequently, the synchronous demodulation module multiplies the differential signal with a reference signal, and extracts a direct current component proportional to the signal amplitude through a low-pass filter; the obtained voltage amplitude signal is input into the data acquisition and processing module; the application can significantly amplify the weak signal related to the film thickness, effectively suppress common-mode noise, obtain nanometer-level thickness resolution, and has a high signal-to-noise ratio.

The utility model provides a contra-rotating ducted fan power device which comprises a ducted shell, a center body, a rotating mechanism, a supporting mechanism and a driving mechanism, the center body, the rotating mechanism, the supporting mechanism and the driving mechanism are arranged in the ducted shell, a ducted inner space is formed in the ducted shell, and the center body is arranged in the center of the ducted inner space. The rotating mechanism, the supporting mechanism and the driving mechanism are all connected to the center body, the supporting mechanism is connected to the middle position of the center body, the driving mechanism is in transmission connection with the rotating mechanism, and the rotating mechanism comprises a first rotating mechanism body and a second rotating mechanism body; according to the contra-rotating ducted fan power device, the rotating directions of the two rotating mechanisms are opposite, the contra-rotating rotating mode can balance torque generated by rotating blades, vibration is reduced, the stability of a system is improved, the service life of the system is prolonged, meanwhile, the contra-rotating blades neutralize the eddy current effect, tail flow kinetic energy loss is reduced, and the service life of the system is prolonged. Therefore, higher thrust efficiency is realized.

The invention discloses a motor self-adhesive coil heating system in a high-temperature airflow environment, and the system comprises an airflow guiding and preprocessing layer which employs a titanium alloy-ceramic composite channel and is internally provided with a spiral guide plate; the micro-channel heat exchanger is integrated, air flow is pre-cooled, and the air flow temperature is reduced; the self-adhesive coil efficient heating layer balances heating and heat dissipation through a layered winding process, the eddy current effect is enhanced through dense winding of the bottom layer, congestion of magnetic lines is relieved through sparse winding of the middle layer, and an induction heating coil is adopted for the top layer. Graphite radiating fins are embedded between the layers; the active heat dissipation enhancement layer is used for guiding out heat of the coil layer through triple mechanisms of a heat pipe array, a paraffin-based phase change material and a liquid cooling loop; and the intelligent heat management and control layer is used for deploying a fiber grating sensor to monitor a three-dimensional temperature field in real time, dynamically adjusting heating power and heat dissipation intensity in combination with a PID algorithm, setting a three-level temperature threshold value, triggering an emergency heat dissipation mechanism when extreme high temperature is detected, and synchronously sending a safety signal to the airflow pretreatment layer to optimize airflow parameters.

The invention relates to an automobile drive-by-wire pedal angle sensor, which comprises an inductance module circuit, a Hall module circuit and a Hall switch circuit, and is characterized in that when a pedal is treaded down, the inductance module circuit outputs a voltage signal to a conditioning chip for signal amplification, compensation and conversion, and finally outputs a corresponding tent signal; the Hall module circuit outputs a voltage signal to the conditioning chip for signal amplification, compensation and conversion, and finally outputs a corresponding tent signal; the Hall switch outputs a high-low level; at the moment, the current signal and the high-low level of the switch are transmitted to an automobile braking and control system, so that an ECU (Electronic Control Unit) takes corresponding measures to each related module of the automobile. On the basis of the eddy current effect principle, a heterogeneous structure is added, two paths of inductance output are added, four paths of signals can be redundant in pairs, and the risk of common cause failure is reduced.