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In this study, a low-cost, innovative, and non-intrusive rotor position detection system and the phase excitation algorithm were proposed for the external rotor switched reluctance motor (ERSRM). The benefits of the developed rotor position sensing system are its low cost and the accurate detection of the starting position of the rotor. Also, the rotor speed was calculated in real-time using the developed system. Another benefit is that the phase excitation signals are directly generated from this system. Therefore, the complexity of the control algorithm is reduced. To prove the effectiveness of the position sensing system, the motor was operated with the proportional–integral (PI) speed controller. The designed speed controller was implemented on the Texas Instruments (TI) TMS320F28379D Launchpad and experimentally tested. The control results given in section 4 showed that using the phase excitation signals coming from the developed Hall effect sensor-based rotor position detection system, the motor was operated successfully with low torque ripple. A comparison was made between the presented technique and the state of the art in terms of torque ripple, and it was explained in the conclusion section. [ABSTRACT FROM AUTHOR]

A Helmholtz-type electromagnetic emission device, which uses an oscillating magnetic field (OMF), with potential applications in biotechnological research, was built and validated. The coils were connected to an alternating current (AC) generator to generate a 0.5 to 110 mT field at their center. OMF measurements were performed with a Hall effect sensor with a digital signal connection (Arduino nano) and data output to a PC using LabVIEW v2017SP1 software. The fermentation process of the cocoa bean variety CCN 51, exposed to four levels of OMF density for 60 min (0, 5, 40, and 80 mT/60 min), was analyzed. Different variables of the grain fermentation process were evaluated over six days. The ANOVA test probed the device's linearity, accuracy, precision, repeatability, reliability, and robustness. Moreover, CCN 51 cocoa beans' EMF-exposure effect was evaluated under different OMF densities for 60 min. The results show the validity of the equipment under working conditions and the impact of EMF (electromagnetic fields) on the yield, deformation, and pH of cocoa beans. Thus, we concluded that the operation of the prototype is valid for use in biotechnological studies. [ABSTRACT FROM AUTHOR]

Fault-tolerant control (FTC) is a design methodology that ensures control systems continue to function even with component faults or failures. FTC is particularly used in Brushless DC Motors (BLDC), electric motors that use electronic commutation instead of brushes. These motors use three Hall effect sensors, placed 120 degrees apart, to accurately determine the rotor's position and control its speed and torque. This paper presents a methodology using electronic logic gates to compensate for sensor faults by analyzing the behavior of the Hall effect signals, translating them into binary language, and enabling continued control of the BLDC motor. This methodology improves the fault-tolerant capability of BLDC motors and ensures their continued functioning despite component failures. Simulation and validation results using Matlab/Simulink demonstrate the effectiveness of the proposed methodology in ensuring the continued operation of the BLDC motor despite component failures. The proposed fault-tolerant control strategy can enhance the reliability and performance of BLDC motors, making it a valuable tool for various industrial applications. [ABSTRACT FROM AUTHOR]

In this work we present the construction of a magnetic field meter (gaussmeter) with high sensitivity and detection from 1 to 80 mT, consisting of simple electronic components, with a proposal of application in an experimental setup for the generation of pure spin currents through the effect spin Seebeck. Through a USB cable, the device is powered and exchanges data with a computer via communication in C++ language with Arduino Uno, together with a LabVIEW graphical interface. To perform measurements in deep environments, such as inside electromagnets, a Hall probe was developed. The equipment also has an LCD screen. The magnetic field sensor used is the SS49E, with which it was possible to obtain measurements with appropriate resolution and range. The developed gaussmeter was used in the development of an experimental setup for investigations of the spin Seebeck and spin Hall effects, where it was possible to estimate the spin Hall angle for bilayers formed by a platinum (Pt) film grown on a YIG insulating magnetic film. Therefore, the developed gaussmeter has the potential to be used both in teaching and research environments and its main advantage is the low production cost, approximately US$ 22.00. [ABSTRACT FROM AUTHOR]

Insulation degradation may cause inefficient and faulty operation of transformers. The insulation failures in transformers mostly start with a Partial Discharge (PD) event. For both operational and cost reasons to ensure the best performance and functionality of transformers, early detection of PD events is of great importance. In this paper presents a novel PD detection technique by using a highly sensitive Quantum Well Hall Effect (QWHE) magnetic field sensor and compares the findings with an off-the-shelf silicon magnetic field transducer. The investigation of the QWHE for high voltage engineering problem such as PD detection is given first time in this paper. The aim of the study is to detect PD activity in pressboards immersed in mineral insulation oil experimentally using a new QWHE sensor. The measured experimental data from both sensors are decomposed by Empirical Mode Decomposition (EMD) and Wavelet Decomposition (WD) methods, and PD signals are analyzed comparatively. The results show that QWHE sensors provide more accurate and noise-free measurements allowing early and more accurate PD detections.

The procedure for determining the frequency-weighted RMS values of vibration accelerations in the case of petrol chainsaws proposes equal time shares of three operation modes of the chainsaw. In order to assess the actual operator’s vibration exposure, it is necessary to precisely determine the above-mentioned shares. In real-life conditions operation of chainsaws is characterized by frequent and significant rotational speed changes depending on the operation mode. Therefore, a prototype of dedicated device for measuring the rotational speed of a chain sprocket was developed. The article presents development requirements, encountered problems and their solutions, the prototype itself and functional test results.

Developing technology enables more accurate and efficient measurement with the help of low-cost sensors. Therefore, in this study, a gaussmeter that can be used for agricultural purposes was developed using a low-cost microcontroller development card. The developed low-cost gaussmeter includes an inexpensive magnetic field sensor, a microcontroller development card, and LabVIEW software. Magnetic field measurements, based on the optimization of the microcontroller-based gaussmeter, were developed with the HAL503 Hall Effect sensor with the help of LabVIEW software. A high regression was observed between the values obtained from the device and the results found from the calculations made using theoretical magnetic field formulas and the measured values. It was observed that it works with an average accuracy of 99.6% for 3 different thickness magnets. According to the developed measuring device results of 6, 8, and 10 magnets sizes, R2 values were evaluated as 99.8%, 99.7%, and 99.3%, respectively.

A Helmholtz-type electromagnetic emission device, which uses an oscillating magnetic field (OMF), with potential applications in biotechnological research, was built and validated. The coils were connected to an alternating current (AC) generator to generate a 0.5 to 110 mT field at their center. OMF measurements were performed with a Hall effect sensor with a digital signal connection (Arduino nano) and data output to a PC using LabVIEW v2017SP1 software. The fermentation process of the cocoa bean variety CCN 51, exposed to four levels of OMF density for 60 min (0, 5, 40, and 80 mT/60 min), was analyzed. Different variables of the grain fermentation process were evaluated over six days. The ANOVA test probed the device’s linearity, accuracy, precision, repeatability, reliability, and robustness. Moreover, CCN 51 cocoa beans’ EMF-exposure effect was evaluated under different OMF densities for 60 min. The results show the validity of the equipment under working conditions and the impact of EMF (electromagnetic fields) on the yield, deformation, and pH of cocoa beans. Thus, we concluded that the operation of the prototype is valid for use in biotechnological studies.

The ability to precisely measure magnetic fields under extreme operating conditions is becoming increasingly important as a result of the advent of modern diagnostics for future magnetic-confinement fusion devices. These conditions are recognized as strong neutron radiation and high temperatures (up to 350 °C). We report on the first experimental comparison of the impact of neutron radiation on graphene and indium antimonide thin films. For this purpose, a 2D-material-based structure was fabricated in the form of hydrogen-intercalated quasi-free-standing graphene on semi-insulating high-purity on-axis 4H-SiC(0001), passivated with an Al2O3 layer. InSb-based thin films, donor doped to varying degrees, were deposited on a monocrystalline gallium arsenide or a polycrystalline ceramic substrate. The thin films were covered with a SiO2 insulating layer. All samples were exposed to a fast-neutron fluence of ≈ 7 × 10 17 cm−2. The results have shown that the graphene sheet is only moderately affected by neutron radiation compared to the InSb-based structures. The low structural damage allowed the graphene/SiC system to retain its electrical properties and excellent sensitivity to magnetic fields. However, InSb-based structures proved to have significantly more post-irradiation self-healing capabilities when subject to proper temperature treatment. This property has been tested depending on the doping level and type of the substrate. [ABSTRACT FROM AUTHOR]

This paper proposes the rotor speed estimation of a squirrel cage induction motor fed by a sinusoidal power supply or an inverter based on the use of a Hall effect sensor installed between two stator slots of the machine. As well known in literature, inverter-fed induction motors usually contains a series of current harmonics and in case of rotor faults, such as broken bars, this operational condition becomes even more severe. The speed estimation has been extensively investigated for its use in control schemes, to compute output power or machine efficiency and particularly for fault diagnosis using motor current signature analysis. In this method, it is necessary an accurate speed estimation to prevent false positives and false negative indications. Therefore, the present research has been carried out by applying the Fast Fourier Transform and Hilbert Transform in the airgap signal measured by the Hall sensor, in order to estimate the rotational speed of the induction motor in a healthy condition and with broken rotor bars. This approach has been compared to the same signal processing techniques using the stator current phase, usually used for speed estimation in the state of the art solutions. The efficiency of this approach was evaluated from simulation and experimental tests, for motor running at distinct load torques, at very low slip conditions and considering a damaged rotor cage. The simulation and experimental results have shown a better accuracy with the measured or simulated speeds, using the airgap estimations when compared to those obtained from stator current processing. [ABSTRACT FROM AUTHOR]

Manyetik sıvı hipertermi (MFH) geliştirilmekte olan yeni nesil kanser tedavi yöntemlerinden biridir. MFH’nin pratik uygulamalarında ortaya çıkan zorluklardan biri manyetik nanoparçacıkların (MNP) sınırlı kontrolüdür. Bu sorunun üstesinden gelebilmek için MFH testlerinde yeni yaklaşımlar araştırılmaktadır. MNP salınımlarının bölgeselleştirilmesi sabit mıknatıs veya elektromıknatıslar tarafından üretilen manyetik alansız bölge (FFR) ve statik manyetik alan (SMF) gradyanları aracılığıyla sağlanabilir. Bu çalışmada elektromıknatıslara göre teknik ve ekonomik avantajlar sunmasından dolayı SMF kaynağı olarak sabit mıknatıslar tercih edilmiştir. Çalışma alanında ortaya çıkacak gradyan örüntülerini kestirebilmek için sonlu elemanlar yöntemi benzetimi kullanılmıştır. Gradyan örüntüsünün parametrik değişimlerle oluşturulacağı platform bilgisayar destekli çizim ortamında tasarlanarak 3B yazıcı ile üretilmiştir. Sabit mıknatıslarla üretilen gradyan örüntüsünün hedeflemeli MFH kullanımı için haritalanması bu çalışma ile ilk defa ele alınmıştır. Elde edilen bulgular tümör tipine göre hangi gradyan örüntüsünün kullanılabileceği hakkında bilgiler sunmaktadır.

In the development of smart home products, energy monitoring, and control systems, there is a significant need for precise and reliable electric current measurement. Most domestic appliances, whether residential or commercial, are powered by power cords with two wires. A reliable and accurate current probe would be required to detect current in two-wire power cables. Existing current sensors for two-wire power cables are complex, bulky (they use a magnetic core), and need full access to the power cord. In this paper a coreless, contactless current probe that requires only limited access of the space around the two-wire power cable is proposed. The sensor unit presented here measures the current accurately even for certain types of misalignments of the power cord. This makes the current measurement less sensitive to minor mechanical displacements, radius of the conductors, and the overall insulation thickness of power cord. In the proposed current probe, one-of-a-kind and highly reliable arrangement of magnetic field sensors, are used to measure the magnetic flux density caused by the current passing in the power cord. The current is computed using a derived mathematical formula which is expressed in terms of the voltage outputs of the magnetic sensors. To provide a clear understanding of the measurement process, an analysis using the Finite Element Method (FEM) is performed. The functionality of the proposed current probe is theoretically tested. Considering different sources of errors, an accuracy of less than 1.5% is obtained. [Display omitted] • The proposed current probe does not require 360° space around the power cord, this method requires only partial space by the side of the power cord. • The proposed probe enables distance-independent current measurement, varying based on power cord insulation thickness and diameter. • The probe offers efficient, simple, cost-effective current measurement in power cords with three magnetic sensors. • To keep up with the errors, mathematical analysis was done with finite length of the power cord. • In addition, FEM analysis validated in presence of ferromagnetic materials and with interference due to external magnetic field. [ABSTRACT FROM AUTHOR]

Hall effect sensor is a very frequently used sensor in mechatronic products. There is little information in the catalogue sheets about the application possibilities of this type of sensor. This article examines the configuration options of this sensor and how to use it to achieve the best measurement uncertainty and minimal hysteresis. [ABSTRACT FROM AUTHOR]

Copyright of Yuzuncu Yil Universitesi Journal of Agricultural Sciences (YYU J Agr Sci) is the property of Yuzuncu Yil University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The procedure for determining the frequency-weighted RMS values of vibration accelerations in the case of petrol chainsaws proposes equal time shares of three operation modes of the chainsaw. In order to assess the actual operator’s vibration exposure, it is necessary to precisely determine the above-mentioned shares. In real-life conditions operation of chainsaws is characterized by frequent and significant rotational speed changes depending on the operation mode. Therefore, a prototype of dedicated device for measuring the rotational speed of a chain sprocket was developed. The article presents development requirements, encountered problems and their solutions, the prototype itself and functional test results. [ABSTRACT FROM AUTHOR]

A mechatronic-based embedded system was used to measure and display the dynamic wheel axle torque and tractive force of different tractor-implement combinations. It included a special transducer to measure drive wheel torque of a tractor, and an embedded telemetry digital system to receive, process and record the data in SD card module. The observed dynamic wheel axle torque under various tillage operations using different implements were compared with the theoretical values using traction models of Brixius (1987), Wismer and Luth (1973) and Tiwari (2006) to find the model suitable for sandy clay loam soils. The results were compared using the gross traction ratio and motion resistance ratio. Maximum variation of (+) 35% was observed between the developed system and the theoretical calculated values using Brixius (1987) and Wismer and Luth (1973) models, while Tiwari (2006) model had maximum variation of (+)14 per cent.

Efficient health monitoring for identifying and quantifying damages can substantially improve the performance and structural integrity of engineered systems. Specifically, new advances in sensing technologies have pushed the research of large sensor networks to monitor complex mechanical structures. Given the need for health state monitoring, designing an optimal sensor framework with accurate detectability of failure modes has great significance. However, there is often little to no experimental data available for newly proposed mechanical systems; so a digital-twin method would make fault detection feasible for this applications. In this paper, a data-driven reliability-based design optimization (RBDO) approach is employed for sensor placement and fault detection of a permanent magnet synchronous motor (PMSM), which is a relatively new system for high power engineering applications. This system suffers from inter-turn and inter-phase short-winding faults, which can cause catastrophic failure of the whole structure. For PMSMs, current sensing and magnetic field sensing can be utilized for the detection of faults, but actual sensor placement has not been considered in recent literature. In this study, the first step is to create an FEA model of the PMSM for the simulation of faults, which serves as the digital twin. Next, a data-driven approach is implemented for sensor placement and classification of faults. The proposed method utilizes distance clustering for identification of various failure modes, which is suitable for many applications due to its high accuracy and computational efficiency. In addition, a genetic algorithm is implemented to determine the minimum number and optimal placement of sensors. This framework simultaneously searches for the optimal placement of sensors while training the classifier for detectability of system health states. Ultimately, the proposed methodology shows convergence to a solution with high accuracy for detection of faults, and is demonstrated on the novel system of a PMSM with magnetic field sensors. • Developed a new fault diagnosis method for permanent magnet synchronous motor (PMSM). • The study jointly considered sensor placement and PMSM fault detection. • A PMSM digital-twin was created with physics-based finite element modeling of faults. • Digital-twin models generated varying magnetic flux signals with different PMSM faults. • Optimized sensor placement was obtained using a reliability-based design approach. [ABSTRACT FROM AUTHOR]

Goal: Gauss Meter Model X01.  Gauss meter model X01 is the hand-held device designed to meet the needs of magnetic industry to measure magnetic fields accurately, provided high-end functionality and performance in an affordable laptop instrument. Magnet testing and sorting have never been easier. Additional features including calculating magnetic field intensity versus time and displaying magnetic field direction on a Graphical User Interface on Computer.  Introduction/Background:  Magnetic fields are invisible to the naked eye but yet there is a need to detect magnetic fields for applications in manufacturing industry and research. Applications include testing of electromagnetic machinery like electric motors to see if it works correctly, or to detect magnetic field properties like mapping landscapes. A gaussmeter can use Hall Effect sensors that utilize the Hall Effect to detect perpendicular magnetic field intensity. The Hall Effect causes a voltage to be developed between two terminals on a conductor if there is a perpendicular magnetic field and a current going through the conductor. There are a range of capabilities that are present in the market for gaussmeters. A gaussmeter can be simple enough to just tell users the magnetic field intensity as a scalar or it can have many advanced features including computer linking, 3-D sensing, and measurement of AC magnetic fields.   Advisor: Professor Henry Lee.  UCI Dean's Choice Award

The ability to precisely measure magnetic fields under extreme operating conditions is becoming increasingly important as a result of the advent of modern diagnostics for future magnetic-confinement fusion devices. These conditions are recognized as strong neutron radiation and high temperatures (up to 350 °C). We report on the first experimental comparison of the impact of neutron radiation on graphene and indium antimonide thin films. For this purpose, a 2D-material-based structure was fabricated in the form of hydrogen-intercalated quasi-free-standing graphene on semi-insulating high-purity on-axis 4H-SiC(0001), passivated with an Al2O3 layer. InSb-based thin films, donor doped to varying degrees, were deposited on a monocrystalline gallium arsenide or a polycrystalline ceramic substrate. The thin films were covered with a SiO2 insulating layer. All samples were exposed to a fast-neutron fluence of ≈7×1017 cm−2. The results have shown that the graphene sheet is only moderately affected by neutron radiation compared to the InSb-based structures. The low structural damage allowed the graphene/SiC system to retain its electrical properties and excellent sensitivity to magnetic fields. However, InSb-based structures proved to have significantly more post-irradiation self-healing capabilities when subject to proper temperature treatment. This property has been tested depending on the doping level and type of the substrate.

A low-cost teslameter based on a Hall effect sensor MLX90242 is proposed in this paper. The proposed teslameter is built around a PIC18F4550 microcontroller and it can measure magnetic flux density in the range between -55 mT and 55 mT. Temperature stability of measurements originates from the MLX90242 sensor itself. In order for the proposed transducer to be accurate, it has undergone a calibration procedure using a highly accurate teslameter employed as reference instruments and high-quality variable-field electromagnet. The proposed teslameter can store measurements on a PC via built-in USB communication. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. III43014]

This paper provide a preliminary study of a way exploitation energy compressed air converting it in rotational mechanical energy. To comply with this goal, a test bench was assembled with a 0.06 m3 air storage tank, a two piston pneumatic engine, a dynamometer with the electromagnetic breake and dynamic torque sensor to determine engine power, a control system with PLC to monitoring-controling the equipment and Also a data acquisition system to register the process variables. A variable time air injection system was included that was electronically controlled through a Hall sensor and a sync disc that It transformer the piston lineal position in a rotary position. The pneumatic engine was built from a two piston air compressor, the power obtained was 52 W and the rotational torque obtained was 2,5 N.m taking into account that the injection time influenced in the results. The efficiency obtained was between 7-11 %. [ABSTRACT FROM AUTHOR]

Wireless capsule endoscope (WCE) is a new diagnostic device that can be utilised for evaluating the whole digestive tract if effectively actuated. In this research, a new one degree of freedom (1DOF) actuation system based on a magnetic levitation concept is proposed for the capsule endoscope navigation system. The proposed system is used to move a permanent magnet inserted in WCE body by an arrangement of the current controlled electromagnetic actuator placed on a 3DOF movable frame. The aim of this study is to design a proportional–integral–derivative (PID) controller to suspend the capsule and keep it at a demand test region. DC and AC magnetic field‐based positioning systems using the Hall effect sensor and the coil sensor, respectively are used to provide the controller by capsule position feedback. Improvement of the position feedback accuracy based on AC magnetic field using discrete Fourier transform is presented. Realistic simulation design of the system is implemented using Matlab/Simulink environment to validate the PID controller. The navigation scheme is implemented practically utilszing digital signal processor to verify the effectiveness of the controller. Finally, simulation and experimental results of the capsule navigation system are presented to show the performance of the proposed controller. [ABSTRACT FROM AUTHOR]

The method of direct continuous measurement of the angle of attack of an aerophysical missile complex, with the use of a Hall effect sensor, when in motion in its path for the numbers of Mach of the flow М∞ ≤ 4.5, Reynolds along the forebody length ReL,∞ ≤ 108, acceleration а ≤ 32 g under the operation of a dual- thrust rocket engine (DTRE) is presented. The airborne electronic measurement system of the aerophysical missile complex, including the silicon Hall effect sensor as a sensor of the missile complex orientation in relation to the full vector of the Earth's magnetic field in this experiment, is described in detail. The Hall effect sensor has been installed between the two concentrators of magnetic flux from permalloy plates to amplify the Earth's magnetic field. The voltage in the magnetic field measurement channel has been determined by the dependence of u  K·H, where K is the meter conversion coefficient, H is the projection of the magnetic field intensity vector on the meter. A signal from the Hall effect sensor has arrived at the magnetic storage. Based on processing the path data on the angle of elevation, azimuth and range, it is found that the direction of a vector of free external stream velocity in flight of the missile complex with the operating DTRE has not changed, and the angle between the axis of this complex and the full vector of the Earth's magnetic field has been constant. This has enabled to conclude that the angle of attack in flight of the aerophysical missile complex is equal to zero with a precision of 0.3. The result corresponds to the known theoretical data and is important for the calculation of thermal flows, surface friction resistance, bottom resistance in the presence of laminar-turbulent transition, turbulent regime of wall boundary flow and its relaminarization on streamlined surfaces. Based on flight data, a scheme of the aerophysical complex for measuring the angle of attack of an uncontrolled supersonic rocket with the aim of studying its oscillations and the problem of flight stability in the active and passive sections of the trajectory is proposed. [ABSTRACT FROM AUTHOR]

Commonly, three Hall effect sensors are used to detect the rotor position in brushless motors. Since one of these sensors may fail and lead to unstable operation, fault-tolerant control (FTC) of Hall sensor drives has attracted renewed research attention recently to ensure very high reliability. This article presents simple combinatory functions to detect fails in Hall effect sensors based only on Hall sensors signals, which require just a memory of 3 b. The proposed method guarantees more reliability and overcomes erroneous alarms that can be triggered by previous fault diagnosis methods using the information on the observed acceleration, which may be the subject of unexpected variations and lead consequently to false diagnosis. In addition, the article opens the discussion about the BLDC startup with a faulty sensor, in order to perform FTC algorithms ensuring a long use of the motor given the difficulty to repair Hall effect sensors inserted between the coils inside the stator. To confirm the theoretical analysis, experimental results are reported and limitations on the performances of the faulty system in terms of fault detection and signal reconstruction algorithm are discussed. The proposed schemes circuits can be inserted in conventional drive systems or by being placed between the existing driver and the motor. [ABSTRACT FROM AUTHOR]

In order to develop a PM BLDC motor control system, which will be tolerant of selected faults, simulation work was first performed and then verified on a universal test stand. The results were published in earlier works. The next stage of works was the implementation of previously developed algorithms on the target research test stand – in this case, the prototype vehicle. This last stage of the laboratory work has been presented in this article, i.e. it has been presented the results of experimental research related to the reproduction of rotor angle position, used after the detection of a rotor position sensor fault. A new test stand with the laboratory prototype of a vehicle with two PM BLDC motors is presented. A zeroth-order algorithm (ZOA) was used as a fault compensation method. The effectiveness and usefulness of the previously proposed methods have been confirmed.

Online monitoring and diagnostics of permanent magnet synchronous motors (PMSMs) is becoming important with the increasing demand in PMSM applications. Most of the research effort focuses on motor current signature analysis (MCSA) as it can provide remote, online monitoring at low cost. However, all types of defects that produce asymmetries in the PMSM rotor or load produce identical rotor rotational frequency components. This is a serious limitation when applying MCSA since it can produce false indications and degrade the sensitivity of fault detection. The requirement of complex time–frequency analysis techniques is another limitation of MCSA for applications with speed variations. In this paper, the feasibility of using analog Hall sensor signals to complement MCSA for detection and classification of rotor- and load-related defects is investigated. It is shown that Hall sensors installed in machines for initial rotor position estimation can be used with minimal hardware modifications to detect and classify signatures produced by the rotor and load for cases where MCSA fails, even during transient conditions. Experimental testing performed on an interior permanent magnet synchronous motor (IPMSM) under eccentricity, local demagnetization, and load unbalance conditions shows that the reliability and sensitivity of fault detection in PMSM systems can be improved at low added cost. [ABSTRACT FROM AUTHOR]

This paper reports on a quantitative technique based on the Magnetic Flux Leakage (MFL) method, for the detection and interpretation of the MFL signals caused by rectangular hairline cracks in pipeline structures. This was achieved through visualization and 3D imaging of the leakage field. This research is aimed at detecting hairline cracks caused by granular bond separation, which occurs during manufacturing, leaving pipelines and steel structures with miniature cracks. The investigation compared finite element numerical simulation with experimental data. The response of the MFL probe scanned above a hairline crack was first predicted using an optimized 3D finite element model. The MFL signals associated with both the surface and far-surface cracks were compared. The results show that the depth, width and length of the various hairline cracks can be estimated by using the distribution pattern and strength of the (Bx), (By) and (Bz) components of the MFL signals. [ABSTRACT FROM AUTHOR]