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A hybrid fluxgate and search coil magnetometer concept using a racetrack core

A hybrid fluxgate and search coil magnetometer concept using a racetrack core

1000 Hz compared to ∼ 5 × 10 −10 nT 2 Hz −1 for the ∼ 10 cm search coil on MMS and ∼ 3 × 10 −11 nT 2 Hz −1 for the ∼ 40 cm search coil on the Van Allen Probes (Hospodarsky, 2016). The coil and preamplifier design will need to be cou- pled with careful optimisation of drive frequency, the self- resonance frequency of the coil, and digitiser resolution to exploit the high search coil gain without exceeding the band- width of the analogue electronics or the digitiser. In particu- lar, the self-resonance of the coil should likely be optimised to align with the baseband search coil bandwidth. Combined with a higher-order low-pass anti-alias filter, this should im- prove the search coil performance while preventing interfer- ence between the search coil and fluxgate actions. It remains to be seen if the sensitivities of the two effects in a hybrid in- strument can simultaneously be made operationally useful. It is also possible that with sufficiently high instrumental sensi- tivity we will discover that the search coil action is contami- nated by Barkhausen noise, caused by periodically saturating the core, at a level that limits the usefulness of the search coil data. This sensor topology should miniaturise to platforms such as CubeSats for which multiple boom-mounted instru- ments are generally impractical, so a single hybrid instru- ment providing even modest sensitivity from DC to 10 kHz could be beneficial.
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Optimized merging of search coil and fluxgate data for MMS

Optimized merging of search coil and fluxgate data for MMS

The MMS mission (Magnetospheric Multiscale; Burch et al., 2015) is comprised of four satellites that are used to measure plasma processes in the Earth’s magnetosphere. The main mission target is the exploration of magnetic reconnection. To support measurements down to electron scales, the satel- lites are flying in a tight formation with distances down to 10 km. One of the main measurement quantities used to char- acterize plasma processes is the magnetic field. It is measured by three instruments which are part of the MMS FIELDS suite (Torbert et al., 2014): the analog fluxgate magnetome- ter (AFG), the digital fluxgate magnetometer (DFG) and the search coil magnetometer (SCM). As the measured plasma structures can have speeds from 10 to 1000 km s −1 , high measurement accuracy in both magnetic field magnitude and timing is required over a wide frequency range, e.g., to cal- culate speed and direction of a front crossing the tetrahedron satellite configuration.
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Magnetic Search Coil (MSC) of Plasma Wave Experiment (PWE) aboard the Arase (ERG) satellite

Magnetic Search Coil (MSC) of Plasma Wave Experiment (PWE) aboard the Arase (ERG) satellite

This paper presents detailed performance values of the Magnetic Search Coil (MSC) that is part of the Plasma Wave Experiment on board the Arase (ERG) satellite. The MSC consists of a three-axis search coil magnetometer with a 200-mm-long magnetic core. The MSC plays a central role in the magnetic field observations, particularly for whistler mode chorus and hiss waves in a few kHz frequency range, which may cause local acceleration and/or rapid loss of radiation belt electrons. Accordingly, the MSC was carefully designed and developed to operate well in harsh radia- tion environments. To ascertain the wave-normal vectors, polarizations, and refractive indices of the plasma waves in a wide frequency band, the output signals detected by the MSC are fed into the two different wave receivers: one is the WaveForm Capture/Onboard Frequency Analyzer for waveform and spectrum observations in the frequency range from a few Hz up to 20 kHz, and the other is the High Frequency Analyzer for spectrum observations in the frequency range from 10 to 100 kHz. The noise equivalent magnetic induction of the MSC is 20 fT/Hz 1/2 at a frequency of 2 kHz, and the null depth of directionality is − 40 dB, which is equivalent to an angular error less than 1 ◦ . The MSC on board the Arase satellite is the first experiment using a current-sensitive preamplifier for probing the plasma waves in the radiation belts.
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CLUSTER–STAFF search coil magnetometer calibration – comparisons with FGM

CLUSTER–STAFF search coil magnetometer calibration – comparisons with FGM

At higher frequencies for which the telemetry does not per- mit one to get the waveform, the onboard Spectrum Anal- yser is part of the STAFF experiment. In addition to the three search coil output signals, the Spectrum Analyser receives the signals from the four electric field probes of the EFW ex- periment. These are used to form a pair of orthogonal electric field dipole sensors. All five inputs (2 × E + 3 × B) are used to compute in real time the 5 × 5 Hermitian cross-spectral matrix at 27 frequencies distributed logarithmically in the frequency range 8 Hz to 4 kHz. The components in the spin plane are despun onboard. All channels are sampled simul- taneously, and the integration time for each channel is the same as the overall instrument time resolution, which can be commanded to values between 125 ms and 4 s. The five auto- spectral power estimates are obtained with a dynamic range of approximately 100 dB and an average amplitude resolu- tion of 0.38 dB. The ten cross-spectral power estimates are normalised to give the coherence. The precision of the phase depends upon the magnitude of the coherence: for a signal with magnitude in the highest bin, it is approximately 5 ◦
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CalMagNet – an array of search coil magnetometers monitoring ultra low frequency activity in California

CalMagNet – an array of search coil magnetometers monitoring ultra low frequency activity in California

A high pass analog filter rolls off the gain below 0.25 Hz to suppress the monotonic increase in signal strength at lower frequencies. An anti-aliasing, analog filter rolls off the gain above 12 Hz to suppress 60 Hz noise while still allowing de- tection of the first Schumann resonance. During calibra- tion, coil characteristics are optimized to achieve high co- herence between separate coils, greater than 99%. After field measurements during system testing, an additional filter was installed to further reduce 60 Hz noise contamination. An analog, 5-pole Butterworth filter with a 11.5 Hz cutoff fre- quency was installed to provide a total of 100 dB attenuation at 60 Hz.
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Investigation of VLF and HF waves showing seismo-ionospheric anomalies induced by the 29 September 2009 Samoa earthquake (=8.1)

Investigation of VLF and HF waves showing seismo-ionospheric anomalies induced by the 29 September 2009 Samoa earthquake (=8.1)

In order to clear up uncertainties for earthquake anomaly detection, this study is based on a few types of precursors and experiments. We have analyzed the variations of electro- magnetic spectrograms retrieved by ICE (Instrument Champ Electrique) and IMSC (Instrument Magnetic Search Coil) ex- periments data concerning the closest DEMETER satellite approaches to the Samoa earthquake epicenter from 1 Au- gust to 5 October 2009. The characteristics of Samoa earth- quake accompanied with its aftershocks information can be found in Table 1 and a map is shown in Fig. 1. Optimum distance between the satellite and the earthquake epicenter was selected in terms of DEMETER satellite altitude and earthquake zone radius. The radius of seismic area can be estimated using the Dobrovolsky formula R =10 0.43M where R is the radius of the earthquake preparation zone, and M is the earthquake magnitude (Dobrovolsky et al., 1979). To take into account this distance, data have been selected when orbits are at ± 10 ◦ in longitude and at ± 2 ◦ in latitude from the epicenter.
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Monitoring and Detection of Short Circuit Fault in Transformer

Monitoring and Detection of Short Circuit Fault in Transformer

The method used in [4,5]is based on leakage flux .this method is used during turn to turn faults in winding for sensing the leakage flux in these method some sensing device are placed next to HV winding.(it can be proximity sensor) leakage flux occurs during TTFs. In this TTF detection the gap between HV winding and sensing element should be allowable. If it affects the whole construction of tank and transformer then it is important to change a design. In case of online problem the circuit used for detection of TTF is get protected from high voltage surge and all not able to found faulty location of abnormal condition at winding. In [6] Search coil method , The search coil is placed near the HV winding in transformer is used to detection of turn to turn fault .In normal condition of search coil, core flux and particular part of leakage flux are passing through the search coil ,In search coils during TTF there is drop of fault in the particular part and rise in flux leakage where it results that decreasing in the magnetic flux line that are travel through the search coil, due to these the generated voltage in respective search coil will drop out. These structure has been presented in this paper is for up to 2.5 KVA transformer therefore it is mandatory to provide a insulation layer between the search coil in HV winding which is used for online application where high voltage power transformer get permanently installed .somewhere for small TTF travelling flux cannot be changed which is also enable to change. Therefore the high sensitivity does not get effectively by this method.
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Optimization Method of Magnetic Coupling Resonant Wireless Power Transmission System with Single Relay Coil

Optimization Method of Magnetic Coupling Resonant Wireless Power Transmission System with Single Relay Coil

Although the ICPT system has been applied successfully in electric vehicle charging, it still has many problems and challenges. References [4] and [5] optimize the electrical parameters involved in ICPT system. The presented algorithms can help us choose appropriate coil dimension and electrical parameter to cope with the issue of misalignment tolerance. The detailed analysis of different types of wireless charger topologies in electric vehicle charging applications are presented. The different winding designs for wireless transformer are described and compared [6].

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Online Full Text

Online Full Text

In this paper, the reactor was modeled with three different methods. In the first method, using laboratory data obtained from Amir-Kabir Olefin unit and the Table Curve 2D software, an optimal value of COT for Ethylene and Propylene is obtained. In the second method, using the Linde software, cracking reactor is simulated at actual temperature, pressure… of operation condition. In the third method, using modeling based on mass balance and energy on the differential element of the coil of reactor and using the model provided by Masoumi et al, the optimum Cot to produce Ethylene and Propylene is obtained. This model was selected because of its acceptable results in comparison with the results obtained from experimental and Linde software. In the third methods, the effect of temperature is studied with constant residence time and constant dilution steam ratio in reactor.
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Failure analysis of cylinder head valve spring in locomotives

Failure analysis of cylinder head valve spring in locomotives

In this project modelling and analysis has been borne out on different materials for helical spring. The materials chosen are chromium, vanadium steel material, low carbon structural steel material; the specifications, modelling and analysis is as follows. While entering the industry, analyses of failures have been taken place. Coil spring got more number of failures in the industry. While passing through the case file, the analysis of spring failures, load, heat and manufacturing defects has been founded. The result in failure has overcome through founding the machine to test the spring quality. Better check of the spring will result the quality of better spring and no more failure will be occurring in the spring. Heat should be applied to the spring has been found by using ANSYS software.
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Design of Manually Operated Mosquito Repellent Coil Making Machine

Design of Manually Operated Mosquito Repellent Coil Making Machine

A lever is used to move punch rod to downward position for stamping stroke and when released, energy stored due to stamping stroke used as an energy for return stroke. A stamping die is spiral coil shaped mold for spiral shape mosquito incense. A mosquito coil mold consists of cavities of spiral shape with ejecting coil mechanism for coil ejection. During stamping operation, mosquito incense material is filled in mold cavity, this has to eject in return stroke. Using ejecting plates in mold cavity, coil ejection is done smoothly. Another lever is used for pushing ejecting plate for coil ejection. Before design, we have taken some assumption for design, such as diameter of mosquito coil mold, and punch rod as 145mm and 18 mm. Shunt height is the distance between frame plate and the mold die cutting edge. This height represent stamping stoke length required to stamp mold on material.
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Wireless Power Transmission: A Practical Approach and Performance With “InTes Coil”

Wireless Power Transmission: A Practical Approach and Performance With “InTes Coil”

utilized equation, the obtained EMF of solenoid induction is 3.779258 J/C, and Telsa Coils EMF is 1.06223 J/C. Put the induction coil at a place where the highest EMF have obtained by Tesla Coil. Internal process occurred between Induction Coil and Tesla coil’s EMF. And adding these EMF created by Tesla Coil and Induction Coil. The obtained result or Sum of two different EMF is recognizing as Result 1.The EMF is transmitting through Tesla Coil so it is regarded as Transmitter coil. When we place induction coil at the place of Tesla coil where highest EMF created. The EMF of the Tesla coil working as conductor which convert the electricity. As per the law of electromagnetic induction, Due to changing electric current the conductor is creating electromagnetic waves. And that conductor is considering as an induction solenoid transmitter. So it is also creating EMF. And it is Result 2. We are combing Result 1 and Result 2, it is EMF of InTes Coil.
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Skin Effect in Eddy Current Testing with Bobbin Coil and Encircling Coil

Skin Effect in Eddy Current Testing with Bobbin Coil and Encircling Coil

Eddy current testing (ECT) is widely used in industry for detecting defects in metallic components and ensuring structural safety [1–5]. The technology has many advantages such as single-side testing, being noncontact, and being easy to realize automatic examination. It is well known that the amplitude of EC density is maximum on conductor surface and decreases exponentially with increasing penetrating depth. This phenomenon is called skin effect and is illustrated in Fig. 1. In the figure, the thickness of circular line represents the amplitude of EC density. Due to the skin effect, the capability of ECT for detecting buried defects is limited. To assess the speed of EC attenuation, the normalized EC density is computed by dividing the amplitude of EC density at any depth by the value on conductor surface. Then the speed of EC attenuation is defined as the reduction of normalized EC density per unit depth and is independent of the intensity of the excitation current. The depth at which the normalized EC density equals 1/e (36.7%) is referred to as skin depth. It is essential to have a prior knowledge of skin depth for designing excitation coil and selecting working frequency.
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Noncontact Driving System Using Induction Based Method and Integrated Piezoelectric Ultrasonic Transducers

Noncontact Driving System Using Induction Based Method and Integrated Piezoelectric Ultrasonic Transducers

ven in Table 1. The coils are classified into two groups. Coils in the first group (left column) were used to evalu- ate the effect of N while D was fixed at 1.5 cm. Those in the second group (right column) were used to determine the relation between D and the liftoff characteristic, d, between the Coil-1 and Coil-2. In experiments, both Coil-1 and Coil-2 have the same D and N. In Table 1, d is the liftoff distance between the two coils, and N was set so that each coil had nearly the same Z equip as the coil

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Designing And Implementation Of Wi-Tricity System Control

Designing And Implementation Of Wi-Tricity System Control

4.2.1.1 Coil Manufacturing (Normal Receiver Coil) 32 4.2.1.2 Transmitter coil is connected to 12V step down transformer 32 4.2.3.1 Schematic design of voltage regulator circuit and microcontroller 34 4.2.3.2 Schematic design of IR module and comparator circuit 35 4.2.3.3 Schematic design of transistor relay circuit 35 4.2.4.1 PCB layout design of Wi-tricity system control 36 5.1.1 Block Diagram Simple Wi-tricity System 39 5.1.2 Circuit diagram of simple Wi-tricity system 40 5.1.3 Prototype Model of simple Wi-tricity System with source frequency 43 5.1.4 Relationship between control signal (𝑓 𝑘 ) and voltage of receiver
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Chap 22 EM induction 12 S

Chap 22 EM induction 12 S

field , highest rate of magnetic line of force , highest rate of magnetic line of force being cut by the coil. Hence emf is maximum. being cut by the coil. Hence emf is maximum. • Similarly, when coil is perpendicular Similarly, when coil is perpendicular to the to the

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Design refinement and performance analysis of 12slot 8pole wound field salient rotor switched flux machine for hybrid electric vehicles

Design refinement and performance analysis of 12slot 8pole wound field salient rotor switched flux machine for hybrid electric vehicles

Abstract—Design parameter sensitivity study and performance analysis of 12Slot-8Pole wound field salient rotor (WFSalR) switched-flux machine (SFM) for hybrid electric vehicle (HEV) applications is presented in this paper. The proposed WFSalR SFM consists of 6 armature slots, 6 field excitation coil (FEC) slots and 8 rotor poles. The main advantage of these SFMs when compared with induction machines, synchronous machines, direct current (DC) machines etc is that all the active parts such that armature coil and FEC coil are located on the stator while the rotor part consists of only single piece iron. This makes the machine more robust, simple structure and more suitable to be used for high speed HEV applications. Non-overlap armature and field windings at the stator reduces the copper consumption and also the copper losses. First of all, the initial performance, the main structure and analysis based on two-dimensional Finite Element Analysis under certain limitations and specifications are discussed. Since the initial design fail to attain the maximum torque and power, therefore the performance of machine is enhanced by refinement of several design parameters defined in rotor, FEC and armature slot area. After design refinement, WFSalR FSM has achieved the maximum torque of 22.34 Nm and power of 5.27 kW at maximum field current density, J e of 30 A/mm
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Study on the Vibration Mechanism of the Relay Coil in a Three-Coil WPT System

Study on the Vibration Mechanism of the Relay Coil in a Three-Coil WPT System

Vibration is commonly known as a mechanical phenomenon whereby oscillations occur about an equilibrium point. Types of vibration include forced vibration, damped vibration, and so on. Forced vibration occurs when the object is forced to vibrate at a particular frequency via a periodic input of force. Thus, the vibration of the relay coil is a force vibration. In this study, the force analysis of the relay coil is given. In Figure 7(b), the relay coil can be regarded as a slender rod; the mass of the relay coil m may be concentrated in the geometric center of the relay coil; and the electromagnetic forces f 1 ( t ) or f 2 ( t ) acting on the relay coil are located at the geometric center. When a slender rod
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Design and Development of Mirnov Coil Sensor for Eddy Currents Experiment on Toroidal Vessel

Design and Development of Mirnov Coil Sensor for Eddy Currents Experiment on Toroidal Vessel

Mirnov coil is an induction coil sensor [1, 2], also called search coil sensor or pick up coil sensor or magnetic antenna. It is one of the oldest and well-known magnetic sensors. The induction sensor is practically the only sensor, which can be feasibly manufactured directly by its users unlike the Hall-effect type, magneto restrictive type or fluxgate-type sensors [1]. The technology used for the manufacturing of induction sensor is simple and the materials (winding wire) are commonly available in desired varieties. The operating principle of the coil sensor is nothing but the Faraday’s law of electromagnetic induction. When a varying flux ϕ passes through the coil with cross- sectional area A and number of turns n, a voltage V is induced at the terminals of the coil given by:
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ABSTRACT: The major objective of this project is to build up a device for wireless power transfer (WPT). Wireless

ABSTRACT: The major objective of this project is to build up a device for wireless power transfer (WPT). Wireless

ABSTRACT: The major objective of this project is to build up a device for wireless power transfer (WPT). Wireless power transfer can make an extraordinary change in the field of the electrical engineering which eliminates the use of conventional copper cables and current carrying wires. WPT is based on strong coupling between electromagnetic resonant objects to transfer energy wirelessly between them. The tuned magnetic fields generated by the primary coil can be arranged to interact vigorously with matched secondary windings in distant equipment but far more weakly with any surrounding objects or materials such as radio signals or biological tissues. But for very long distances, microwave transmission is used for the effective transfer of power.
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