Change Of Magnetic Flux Research Articles

Perbandingan Optimasi Kontroler Putaran Motor Permanent Magnet Syschronous Machine

Low torque low owned by PMSM (Permanent Magnet Synchronous Machine) required an excellent control model. PMSM uses the principle of faraday's law by rotating magnets in the coil by using other energy sources. When a magnet moves in a coil or vice versa. The engine rotation will change the magnetic force flux on the coil and penetrate perpendicularly to the coil so that a potential difference arises between the ends of the coil. The potential difference is caused by changes in magnetic flux. in order to get the best control method, a good speed control model is needed. In this study comparing PMSM speed control using PID, Fuzzy Logic Controller (LFC), and Adaptive Neuro-Fuzzy Inference System (ANFIS). The simulation results show that the best model on the ANFIS controller that is closest to Speed ​​Reff (300 rpm) is that ANFIS obtains the rotational profile with the smallest undershot, the fastest steady state, the best output current profile, the best torque profile, and the best voltage profile. The results of this study will be followed by the use of other Artificial Intelligence.

Eddy Current Damping System의 진동 저감 특성 평가

Generally, vibration absorber systems are composed of spring-mass systems to reduce the vibration of a structure, and there are also methods to simply increase damping to achieve a damping effect across a wide frequency band. One similar method is to use a mechanism in which the eddy current is converted into a mechanical damping effect. When an eddy current is generated by electromotive force due to magnetic flux change, the reaction force is generated by the eddy current’s circulation. In this study, the damping system using the reaction force was constructed to reduce the transmission of vibrations generating from internal fluid and the vibration reduction characteristics that are transmitted externally were analyzed. As a result, 8.2 % of the vibration reduction effect from primary excitation frequency was confirmed.

Basic requirements and operating modes for power transformers

Power transformers manufactured in the electrical engineering industry must be highly competitive in the world market in terms of reliability, economy, durability and other important aspects. The effect of the secondary coil MYuK I2w2 on the primary magnetic flux can be explained using the Lents rule. Definition of L e n ts rule: In a closed conductive circuit (chain) connected by an alternating magnetic current, an EYuK is formed in such a direction that the current it generates and the mechanical forces associated with it are inversely proportional to the change in magnetic flux. Basic requirements for power transformers: Power transformers manufactured in the electrical engineering industry must be highly competitive in the world market in terms of reliability, economy, durability and other important aspects.

Structural and cryogenic magnetic properties of rare earth rich RE11Co4In9 (RE = Gd, Dy and Ho) intermetallic compounds.

The crystal structure, magnetic properties and magnetocaloric performances of rare earth rich RE11Co4In9 (RE = Gd, Dy and Ho) intermetallic compounds are investigated systematically in this work. All compounds in this system crystallize in the orthorhombic Nd11Pd4In9-type structure with the Cmmm space group. The stacks of alternate RE and Co/In atomic layers with z = 0, 1 and z = 1/2 along the z-axis constitute the crystal structure. These compounds belong to the REx+yM2yXx family with x = 9 and y = 2, and the ratio of the AlB2-type and CsCl-type fragments in a unit cell is y : x, i.e. 2 : 9. The characteristic of multiple magnetic phase transition is revealed with a low magnetic flux density μ0H of 0.1 T for the present compounds. The ferromagnetic (FM) to paramagnetic (PM) phase transitions of the present compounds around their respective Curie temperatures (TC) are all second order phase transitions (SOPTs). Around the TC of 86, 37 and 20 K for Gd11Co4In9, Dy11Co4In9, and Ho11Co4In9 with a magnetic flux density change Δμ0H of 0-7 T, the values of the maximum magnetic entropy change (-ΔS) and temperature averaged entropy change (TEC) with 3 K span are 10.95 and 10.93 J kg-1 K-1 for Gd11Co4In9, 4.66 and 4.64 J kg-1 K-1 for Dy11Co4In9, and 12.29 and 12.09 J kg-1 K-1 for Ho11Co4In9, respectively. The corresponding values of relative cooling power (RCP) and refrigerant capacity (RC) are 538.1 and 405.9 J kg-1 for Gd11Co4In9, 213.9 and 165.9 J kg-1 for Dy11Co4In9, and 475.2 and 357.4 J kg-1 for Ho11Co4In9, respectively.

Simulation of the pulsating current traction motor

Design and improvement of traction electric engines ensuring reduction of the railway transportation power consumption is a current long-term objective. The objective is to develop technical requirements to the new electric engines, including implementation of the set haulage performance of locomotive, providing for constant power in the certain range of the running speed, as well as required properties in case of the supply network parameters change, selection of the weight and dimensions parameters ensuring fitting of the traction electric engines in the locomotive underframe, and other important tasks. The new technology is proposed for forecasting the engine properties using simulation modeling of the hauling features and electrical characteristics of engine in order to resolve the above mentioned objectives. The proposed pulsating current traction motor model takes into account the eddy currents effect on the processes of magnetic flux changes in the engine steel and the nature of electromagnetic processes in the engine. Electric component of the engine simulation model is added with the torque mechanical balance equation that allows assessing its operating properties to the full extent. Results of calculations are presented in the form of the engine electromotive force attenuation curve calculated for specific mode of operation at the armature current of 780 A and the initial value of electromotive force amounting to 525 V. Obtained parameter of attenuation correlates with the experimental data presented in the other information source. Value of determination factor between the specified curves certifies adequacy of the developed simulation model. Proposed model of engine and methodology of its design allows modeling its operation in transition and in static modes of operation. Engine properties obtained by means of the proposed simulation model n = f(iа) and M = f(iа) are almost similar to the properties of traction engine NB-514 in the entire range of the armature current change iа. Proposed simulation model allows designing pulsating current traction motor with the set operating properties, as well as studying the engine parameters effect on its energy indicators.

Soft Tactile Fingertip to Estimate Orientation and the Contact State of Thin Rectangular Objects

A soft tactile fingertip was developed to provide the contact feedback on characteristics of an object for performing automatic assembly of electronic parts, such as a thin circuit board. However, designing a tactile fingertip with simple design and minimal number of sensors that can estimate orientation and the contact state of an object is a challenging task. This letter presents the simple-structured soft fingertip sensitive to external forces. The fingertip can estimate the grasping force and orientation of a thin rectangular object, and the contact state between the object and the environment based on magnetic flux density (MFD) changes. Two Hall-effect sensors were fixed in parallel at the hard base, and four cylindrical magnets were embedded in the soft body of the fingertip. All parts except the magnets were 3D-printed to simplify the fabrication process. We applied a machine learning approach to define the relationship between the MFD of sensor outputs and object's characteristics. In addition, finite element simulations were performed to evaluate the designed structure. Experimental results verified that the proposed fingertip can estimate the orientation and gripping force of thin rectangular objects. Furthermore, it can successfully classify contact states of the grasped object based on the sensor outputs.

Analysis of a long-duration AR throughout five solar rotations: Magnetic properties and ejective events

Coronal mass ejections (CMEs), which are among the most magnificent solar eruptions, are a major driver of space weather and can thus affect diverse human technologies. Different processes have been proposed to explain the initiation and release of CMEs from solar active regions (ARs), without reaching consensus on which is the predominant scenario, and thus rendering impossible to accurately predict when a CME is going to erupt from a given AR. To investigate AR magnetic properties that favor CMEs production, we employ multi-spacecraft data to analyze a long duration AR (NOAA 11089, 11100, 11106, 11112 and 11121) throughout its complete lifetime, spanning five Carrington rotations from July to November 2010. We use data from the Solar Dynamics Observatory to study the evolution of the AR magnetic properties during the five near-side passages, and a proxy to follow the magnetic flux changes when no magnetograms are available, i.e. during far-side transits. The ejectivity is studied by characterizing the angular widths, speeds and masses of 108 CMEs that we associated to the AR, when examining a 124-day period. Such an ejectivity tracking was possible thanks to the multi-viewpoint images provided by the Solar-Terrestrial Relations Observatory and Solar and Heliospheric Observatory in a quasi-quadrature configuration. We also inspected the X-ray flares registered by the GOES satellite and found 162 to be associated to the AR under study. Given the substantial number of ejections studied, we use a statistical approach instead of a single-event analysis. We found three well defined periods of very high CMEs activity and two periods with no mass ejections that are preceded or accompanied by characteristic changes in the AR magnetic flux, free magnetic energy and/or presence of electric currents. Our large sample of CMEs and long term study of a single AR, provide further evidence relating AR magnetic activity to CME and Flare production.

Measurement of Metal Velocity in Sand Casting during Mold Filling

Melt turbulence during mold filling is detrimental to the quality of sand castings. In this research study, the authors present a novel method of embedding Internet of Things (IoT) sensors to monitor real-time melt flow velocity in sand molds during metal casting. Cavities are incorporated in sand molds to position the sensors with precise registration. Capacitive and magnetic sensors are embedded in the cavities where melt flow velocity is calculated by using an oscillator, the frequency of which is sensitive to changes in the close field permittivity, and change in magnetic flux, respectively. Their efficiency is investigated by integrating the sensors into 3D sand-printing (3DSP) molds for conical-helix and straight sprue configurations to measure flow velocities for aluminum alloy 319. Experimental melt flow velocities are within 5% of estimations from computational simulations. A major benefit of 3DSP is the geometrical freedom for complex gating systems necessary to reduce turbulence and access to mold volume for sensor integration during 3DSP processing. Findings from this study establish the opportunity of embedding IoT sensors in sand molds to monitor metal velocity in order to validate simulation results (2–5% error), compare gating systems performance, and improve foundry practice of manual pouring as a quality control system.

Toward a 0.33 W piezoelectric and electromagnetic hybrid energy harvester: Design, experimental studies and self-powered applications

In this paper, we present a 0.33 W piezoelectric and electromagnetic hybrid energy harvester to tackle the problem of efficiently harnessing energy from low-frequency vibrations. Two types of transduction cores-one piezoelectric element and two sets of magnets and coils, are embedded into a compact design. Several techniques are employed to enhance the performance of the harvester. A pair of truss mechanisms are added into the system to amplify the strain of the piezoelectric element. A stopper is used to induce impact to take advantage of the frequency up conversion effect as well as nonlinearity. We used an array made of multiple small cubic magnets and alternative magnet arrangement rather than one magnet block, for abrupt magnetic flux density changes. Experimental results based on a fabricated prototype validate the proposed techniques that work collectively and enable the harvester to yield a maximum peak power more than 0.33 W at resonance under an excitation of 0.70 g. We also examined the capability of the harvester for self-powered applications. The harvester displays excellent charging performance to millifarad or farad-scale capacitors. An LED array consisting of 99 diodes was lit up in real time. More importantly, experimental results indicate that not just can the harvester simultaneously power a temperature and humidity sensor, and a calculator, but also when the excitation stops, the remaining charges stored can power them for ~20.38 min and ~8.33 min, respectively. This study can be of great significance for high-performance energy harvesting and further development of self-powered sensing and battery-free electronic systems.

Study on the electromagnetic fields of a novel small-angle transducer used in high-precision inertial sensors

PurposeMicrosyn signal generators have been used in high-precision inertial sensors for their good structural stiffness and high sensitivity. However, as the stator and the rotor of the microsyn are both constructed of silicon-steel laminations with high permeability, an extremely small non-concentricity between the stator and rotor of microsyn will cause two random reaction torques acting on the output axis. As a result, difficulty arises in compensating for these random reaction torques. This study aims to investigate the electromagnetic fields of a novel angular transducer characterized by high sensitivity.Design/methodology/approachBased on the operation principles of the new transducer, the output voltage is decided by the time rate of change of the net magnetic flux of each output pole. The transient analysis of the electromagnetic field of the transducer is carried out by ANSYS Maxwell-3D.FindingsThe distributions of the magnetic flux of the transducer’s interior and eddy current on the rotor are consistent with the results of theory analysis. Moreover, the leakage flux mainly distributes nearby the excitation poles. The novel small-angle transducer also possesses a remarkably low reaction torque and power loss.Practical implicationsStudy on the electromagnetic fields of the new transducer not only provides a powerful basis to further improve the precision of the new transducer but also expands the scope of applications of the new transducer.Originality/valueThis new transducer is not only characterized by a high sensitivity, high linearity and fast response but also extremely low reaction torque and power losses. Thus, the new transducer is suitable for high-precision inertial sensors.

On the detection interfaces for inductive type tactile sensors

This study presents the investigation of detection interface for the inductive type tactile sensor consisted of a polymer encapsulated CMOS chip with coils and a magnetic bump. The normal tactile load will change the distance between the magnetic bump and coils, and the tactile load is then detected by the magnetic flux change of the coils. Thus, the detection interfaces include (1) the magnetic bump which acts as the contact interface, and (2) the coils (on the CMOS chip) which act as the signal pick-up interface. For the contact interface, the size and material of the magnetic bump will influence the magnetic flux of the inductive tactile sensor. The signal outputs resulted from the magnetic tactile bumps of different materials and sizes are studied. Moreover, the force responses, hysteresis measurements, and misalignment issues for magnetic bumps of different sizes are also investigated. For signal pick-up interface, two coil designs are presented to offer different sensing approaches for the inductive tactile sensor. Since the CMOS chip is implemented using the commercially available standard process (the TSMC 0.35 μm 2P4M CMOS process), multi-layer coils are achieved by using the four metal films.

A new weak-field magnetic DA white dwarf in the local 20 pc volume

We report the discovery of a new magnetic DA white dwarf (WD), WD 0011 − 721, which is located within the very important 20 pc volume-limited sample of the closest WDs to the Sun. This star has a mean field modulus ⟨|B|⟩ of 343 kG, and from the polarisation signal we deduce a line-of-sight field component of 75 kG. The magnetic field is sufficiently weak to have escaped detection in classification spectra. We then present a preliminary exploration of the data concerning the frequency of such fields among WDs with hydrogen-rich atmospheres (DA stars). We find that 20 ± 5% of the DA WDs in this volume have magnetic fields, mostly weaker than 1 MG. Unlike the slow field decay found among the magnetic Bp stars of the upper main sequence, the WDs in this sample show no evidence of magnetic field or flux changes over several Gyr.

Comprehensive Improvement of the Sensitivity and Detectability of a Large-Aperture Electromagnetic Wear Particle Detector.

The electromagnetic wear particle detector has been widely studied due to its prospective applications in various fields. In order to meet the requirements of the high-precision wear particle detector, a comprehensive method of improving the sensitivity and detectability of the sensor is proposed. Based on the nature of the sensor, parallel resonant exciting coils are used to increase the impedance change of the exciting circuit caused by particles, and the serial resonant topology structure and an amorphous core are applied to the inductive coil, which improves the magnetic flux change of the inductive coil and enlarges the induced electromotive force of the sensor. Moreover, the influences of the resonance frequency on the sensitivity and effective particle detection range of the sensor are studied, which forms the basis for optimizing the frequency of the magnetic field within the sensor. For further improving the detectability of micro-particles and the real-time monitoring ability of the sensor, a simple and quick extraction method for the particle signal, based on a modified lock-in amplifier and empirical mode decomposition and reverse reconstruction (EMD-RRC), is proposed, which can effectively extract the particle signal from the raw signal with low signal-to-noise ratio (SNR). The simulation and experimental results show that the proposed methods improve the sensitivity of the sensor by more than six times.

On the possibility of faster detection of magnetic flux changes in a single-photon counter by RF SQUID with MoRe–Si(W)–MoRe junction

The nonhysteretic mode of a RF SQUID with a MoRe–Si(W)–MoRe Josephson junction is analyzed in order to detect the states of a single-photon counter based on a superconducting quantum interferometer with a discrete Hamiltonian. The absorption of a photon with 10 GHz frequency brings the counter to the excited level causing tunnelling into the adjacent potential well and a change in the magnetic flux in the interferometer, which can be detected by the SQUID magnetometer. Measurement of a quantum system requires minimization of the back action of the signal read-out channel at the counter, high sensitivity, and speed of the magnetometer. The MoRe–Si(W)–MoRe contacts are optimized for various concentrations of tungsten (W) in silicon (Si) and barrier layer thickness. It is shown that using MoRe–Si(W)–MoRe contacts with a tungsten concentration of approximately 11% for the RF SQUID at excitation frequencies of ∼1 GHz makes it practically an ideal parametric upward frequency shifter with noise determined by the cooled amplifier.

Analysis of magnetic flux in magneto-rheological damper

Magnetorheological materials are a class of smart substances whose rheological properties can rapidly be varied by application of a magnetic field. The proposed damper consists of an electromagnet and a piston immersed in MR fluid. When current is applied to the electromagnet, the MR fluid solidifies as its yield stress varies in response to the applied magnetic field. Hence, the generation of a magnetic field is an important phenomenon in MR damper. In this research, the magnetic field generated in the damper was analyzed by applying finite element method using COMSOL Multiphysics and was validated using magnetic circuit theory. A quasi-static, 2D—Axisymmetric model was developed using parametric study by varying current from 0–3 A and the magnetic flux density change generated in the fluid flow gap of MR fluid due to external applied current was evaluated. According to the analytical calculations magnetic flux density generated at MR fluid gap was 0.64 Tesla and when calculated using FEA magnetic flux density generated was 0.61 Tesla for 1A current. There is a difference of 4.8% in the simulated results and analytically calculated results of automotive MR damper due to non linear BH curve consideration in Finite element analysis over linear consideration of BH relation in magnetic circuit theory.

Using an Arduino to demonstrate Faraday’s law

We present a semi-quantitative approach to visualize graphically Faraday’s induction law. Using an Arduino board, we can measure both the magnetic field inside a coil and the electromotive force. When we move a magnet close to the coil, it is possible to see on a graph that the electromotive force rises when the magnetic flux changes.

Design of energy harvesting wireless sensors using magnetic phase transition

Many countries have recently become interested in the deployment of cyber-physical systems (CPS) in industry and society for sustainable development. A CPS comprises a data acquisition function, a data storage function, and a network to transfer data. The move to deploy CPS in society makes it necessary to increase their energy efficiency and to find new energy sources. To overcome these energy-related issues, in this research we investigated the possibility of integrating data acquisition sensors with a recently developed energy harvesting system that combines the magnetic phase transition resulting from changes in temperature, and electromagnetic induction resulting from changes in magnetic flux. The proposed system can provide wireless temperature or velocity sensors that directly measure electromotive forces generated by a solenoid following Faraday's law without any additional energy input. Our proposed energy harvesting sensors have the potential to contribute significantly to the development of CPS in the near future.

Solar Quiet Region Jet by Eruption of Minifilament and Associated Change in Magnetic Flux

We observe a coronal jet around 22 : 08 UT on March 23, 2017, in a quiet region towards the north-east of the solar disk. A minifilament eruption leads to this jet. We analyze dynamics of the minifilament from its formation until its eruption. We observe that the minifilament starts forming around 15 : 50 UT. Then at a later time, it disappears but again appears and finally erupts as a blow-out jet around 22 : 08 UT. We study the evolution of photospheric magnetic field beneath the minifilament. Initially, we observe subsequent increase and decrease of positive magnetic flux. Prior to the initiation of the eruption, positive magnetic flux shows a continuous decrease until the minifilament disappears. The positive magnetic flux increases and decreases due to new positive flux emergence and cancellation of positive magnetic flux with negative magnetic flux, respectively.

Algoritma Persaingan Imperialis Sebagai Optimasi Kontroler PID dan ANFIS Pada Mesin Sinkron Magnet Permanen

Permanent Magnet Syschronous Machine (PMSM) has low torque, so good control is needed to be stable quickly. PMSM uses the principle of faraday experiments which is rotating a magnet in a coil or vice versa. When a magnet moves in a coil, there is a change in magnetic flux in the coil and penetrates perpendicular to the coil so that there is a potential difference between the ends of the coil, regarding this due to changes in magnetic flux. Magnetic flux can be changed by moving a magnet in a coil or vice versa by utilizing other energy sources. To get a good optimization result, the right control constants are needed. So that the best output is obtained. To get the right constants, a suitable and good method is needed, including using artificial intelligence. In this study using the Imperialist Competitive Algorithm (ICA) method. From the simulation results it was found that the best controller design in this study was ANFIS-ICA with the best profile, torque profile, voltage profile, and rotation profile. The largest current is 2.45 A, the smallest overshot torque is 0.48 pu, the largest voltage frequency is 9.84 khz, and the best rotation (close to the reference) is 700.02 rpm. The results of this study will be continued with the use of other artificial intelligence.

Kontrol Kecepatan Putaran Permanent Magnet Synchronous Machine (PMSM) Menggunakan PID, FLC Dan ANFIS

Permanent Magnet Syschronous Machine (PMSM) has low torque in a number of specific applications, so a good control model is needed. PMSM uses the principle of faraday experiments by turning a magnet in a coil by utilizing another energy source ... When a magnet moves in a coil or vice versa. Turning the engine will change the magnetic force flux in the coil and penetrate perpendicular to the coil so that there is a potential difference between the ends of the coil. That is due to changes in magnetic flux. To get the best control method, a comparison of several speed control models is needed. In this study comparing PMSM speed control without controller, using PID controller, using FLC controller, and using ANFIS controller. From the simulation results show that the best model on ANFIS controller, which is closest to the Speed reff (300 rpm) is ANFIS obtained the round profile with the smallest undershot of 300,015 rpm at t = 0.0055 seconds and steady state at 300.02 rpm at 0.004 seconds, obtained output current profile best on FLC = 3.39 A, while at ANFIS = 3.38 A, the best torque profile (the smallest overshot) is obtained on the ANFIS controller of 0.28 pu, the best voltage profile (most continuous) on the ANFIS controller is 300.03. The results of this study will be continued with the use of other artificial intelligence.