Hall Sensor Research Articles

Method with reliable accuracy and fast speed for measuring operational current of HTS NI closed-loop coils in steady persistent-current-mode

This study proposes a method for measuring the operational current of high temperature superconducting (HTS) non-insulation (NI) closed-loop coils, which operate in the steady persistent-current-mode (PCM). HTS NI closed-loop coils are promising for many easily-quenching direct-current (DC) applications, where their performance is determined by magnetomotive forces, total number of turns, and dimensions. As the primary interface parameter in an application system, the operational current must be accurately and rapidly measured. Generally, this is achieved by dividing the measured magnetic field by the coil constant. However, even if the influence of the screening current induced field (SCIF) is not considered, existing methods for the coil constant may be disturbed by the performance and location of Hall sensors, or experience a long measuring period. Therefore, a relatively accurate and fast method is proposed in this study, which is based on adjusting the output current of the adjustable power supply and monitoring the coil voltage as an indicator. The proposed method was validated through experiments and simulations using an equivalent circuit model coupled with a finite element method (FEM) model, and its current accuracy can be equivalent to the resolution of the employed power supply. It was demonstrated that this method reduced the requirements for Hall sensor’s performance and location, and has a more reliable accuracy in contrast to the simulation method. Compared to the experimentally conventional method, the proposed method presents a significantly faster speed. The impact of the SCIF was considered and proven to be negligible for the tested pancake coils. Even for coils whose coil constant vibrates owing to the SCIF, this method can be adapted to directly measure various operational currents. Furthermore, it was demonstrated that the measurement error can be influenced by the current discrepancy among turns when the coil is not in the steady PCM, and a procedure for reducing this error was proposed.

A Low-Cost Three-Degree-of-Freedom Position Measurement Method of the Y-type Maglev Planar Motor Based on Hall Sensor

A Low-Cost Three-Degree-of-Freedom Position Measurement Method of the Y-type Maglev Planar Motor Based on Hall Sensor

ЦИФРОВАЯ МОДЕРНИЗАЦИЯ ЛАБОРАТОРНОЙ УСТАНОВКИ ПО ИЗУЧЕНИЮ СТРУКТУРУЫ ПОТОКА В АППАРАТАХ

A laboratory installation has been modernized to study the flow structure in apparatus with a stirrer and in tubular apparatus. The apparatus with the stirrer was replaced; the new apparatus is equipped with a frame stirrer. The rotation of the stirrer is carried out by a stepper motor, which made it possible to change the stirrer speed in a wide range. The support for the stepper motor on the device and the mount of the device to the laboratory stand were 3D printed from ABS plastic. As experiments have shown, for this device it is rational to use the rotation speed range from 100 to 400 degrees per second. The angular velocity value is randomly selected when the controller is turned on. It was decided to abandon analog measuring instruments, so water flow rates were measured with flow meters based on a Hall sensor. The salt concentration was measured using a TDS meter; for this purpose, the sensor was calibrated on solutions with different concentrations at different temperatures. Collecting sensor readings and sending them to the computer was carried out using an arduino duo microcontroller. To visualize the response curves on a computer, a program was written in the julia programming language. For a tubular apparatus, the change in the distribution of indicator concentration in the pipe is additionally shown. For this purpose, a partial differential equation for the diffusion model was solved. The values of the model parameter (back mixing coefficient) were determined based on a variety of experimental data depending on the water flow rate. A web server was created to store data for further processing of experimental results. The server allows, based on the results of the simulation, to determine the parameters of the cellular and diffusion models using several algorithms, as well as to simulate the heat transfer process in a tubular apparatus.

Investigating the effect of Hall effect sensor position error on BLDC motor torque

Investigating the effect of Hall effect sensor position error on BLDC motor torque

High-temperature Thermal Stability of a Graphene Hall Effect Sensor on Defect-engineered 4H-SiC(0001)

High-temperature Thermal Stability of a Graphene Hall Effect Sensor on Defect-engineered 4H-SiC(0001)

A fast continuous-time demodulation circuit for a Hall sensor with stack capacitor offset cancellation technique

A fast continuous-time demodulation circuit for a Hall sensor with stack capacitor offset cancellation technique

A testing platform for frequency response characteristics of linear Hall sensors

A testing platform for frequency response characteristics of linear Hall sensors

MEMS Accelerometer and Hall Sensor based Identification of Electrical and Mechanical Defects in Induction Motors and Driven Systems

MEMS Accelerometer and Hall Sensor based Identification of Electrical and Mechanical Defects in Induction Motors and Driven Systems

GaN Transistors’ Radiated Switching Noise Source Evidenced by Hall Sensor Experiments Toward Integration

GaN Transistors’ Radiated Switching Noise Source Evidenced by Hall Sensor Experiments Toward Integration

Optimizing Detection: Compact MobileNet Models for Precise Hall Sensor Fault Identification in BLDC Motor Drives

Optimizing Detection: Compact MobileNet Models for Precise Hall Sensor Fault Identification in BLDC Motor Drives

Temperature Tests of Miniature Ceramic/Antimony Hall Sensors for ITER and DEMO

Temperature Tests of Miniature Ceramic/Antimony Hall Sensors for ITER and DEMO

Electronic prototype for data collection in situ at the facilities of the Universidad Tecnológica de Altamira

Evaluation of renewable energy sources requires detailed and accurate information, as well as the analysis of natural parameters to discover and leverage new energy sources. This information is obtained through electronic devices. These parameters are crucial for developing policies and strategies, and for using and leveraging sustainable or clean energies. With the aim of collecting real-time weather data, a prototype weather station has been created. This prototype uses the ESP32 Nodemcu card and features Wi-Fi and Bluetooth functions to transmit data to MathWorks' "ThingSpeak" platform. In addition, various sensors have been incorporated to measure different climatic parameters, such as ambient temperature (DS18B20 sensor), humidity percentage (DHT22 sensor), barometric pressure (BMP180) and wind speed (anemometer based on a Hall effect sensor). The data collected can be analyzed with the main goa of gaining an accurate understanding of the climate in a specific region. Therefore, this prototype weather station provides a useful solution for obtaining real-time data on weather conditions.

RANCANG BANGUN ALAT UJI PERIFERAL ESP32 DEVKIT V1 - DOIT 30 PIN

The ESP32 DEVKIT V1 - DOIT 30 Pin Peripheral Board Test Tool is a module that can be used to test the ESP32 DEVKIT V1 - DOIT 30 Pin microcontroller board. The chip of the board is ESP32 developed by Espressif Systems. ESP32 has many features or peripherals that can be used in various projects. Built-in Internet of things (IoT) is one of the leading features that can connect the board to the internet without the need for additional modules from outside. Features or peripherals that can be tested on the ESP32 DEVKIT V1 - DOIT 30 Pin Peripheral Board Test Tool, are digital i/o, ADC & DAC, dual core system, built-in touch sensor, built-n hall sensor, Bluetooth, and Wi-Fi.

Active distance control in multi-capsule endoscopy via closed loop electromagnetic force between capsules.

Capsule endoscopy offers a non-invasive and patient-friendly method for imaging the gastrointestinal tract, boasting superior tissue accessibility compared to traditional endoscopy and colonoscopy. While advances have led to capsules capable of drug delivery, tactile sensing, and biopsy, size constraints often limit a single capsule from having multifunctionality. In response, we introduce multi-capsule endoscopy, where individually ingested capsules, each with unique functionalities, work collaboratively. However, synchronized navigation of these capsules is essential for this approach. In this paper, we present an active distance control strategy using a closed-loop system. This entails equipping one capsule with a sphere permanent magnet and the other with a solenoid. We utilized a Simulink model, incorporating (i) the peristalsis motion on the primary capsule, (ii) a PID controller, (iii) force dynamics between capsules through magnetic dipole approximation, and (iv) position tracking of the secondary capsule. For practical implementation, Hall effect sensors determined theinter-capsule distance, and a PID controller adjusted the solenoid's current to maintain the desired capsule spacing. Our proof-of-concept experiments, conducted on phantoms and ex vivo bovine tissues, pulled the leading capsule mimicking a typical human peristalsis speed of 1cm/min. Results showcased an inter-capsule distance of 1.94mm ± 0.097mm for radii of curvature at 500mm, 250mm, and 100mm, aiming for a 2-mm capsule spacing. For ex vivo bovine tissue, the achieved distance was 0.97 ± 0.28mm against a target inter-capsule distance of 1mm. Through the successful demonstration of precise inter-capsule control, this study paves the way for the potential of multi-capsule endoscopy in future research.

A Novel Combined Method for Measuring the Three-Dimensional Rotational Angle of a Spherical Joint.

To improve the measurement accuracy of the three-dimensional rotation angle of a spherical joint, a novel approach is proposed in this study, which combines magnetic detection by a Hall sensor and surface feature identification by an eddy current sensor. Firstly, a permanent magnet is embedded in the ball head of a spherical joint, and Hall sensors are set and distributed in the ball socket to measure the variation in the magnetic flux density when the spherical joint rotates, which are related to the 3D rotation angle. In order to further improve the measurement accuracy and robustness, we also set grooves on the ball head and use eddy current sensors to synchronously identify the rotation angle of the ball head. After the combination of two signals is performed, a measurement model is established using the RBF neural network by training, and the real-time measurement of the 3D rotation angle of the spherical joint is realized. The feasibility and superiority of this method are validated through experiments. The experimental results indicate that the measurement accuracy is substantially promoted compared to the preliminary measurement scheme based on spherical coding; the average measurement error of the single axis is reduced by 9'9″. The root mean square errors for the measurements of the 3D rotation angles in this proposed method are as follows: pitch angle α has an error of 1'8″, yaw angle β has an error of 2'15″, and roll angle γ has an error of 29'6″.

(Invited) Magneto-Mechanical Micro-Nano Devices with Electrodeposited Magnetostriction Films

Microsystems play an important role in IoT sensors and actuators in the recent information and communication society. Among these, actuators are important elements used in transmitters, acoustic devices, and optical elements, and for those devices, piezoelectric thin films have been used widely. Magnetostrictive materials are expected to have even greater actuation performance than that of the piezoelectric films, but in the magnetostrictive films integration technologies with a high performance have not yet been fully developed. We have developed the film deposition technologies for magnetostriction materials by electrodeposition and apply them to actuators and sensors [1,2]. The FeGa, TbDyFe, and FeCo magnetic materials are known as giant magnetostriction materials [3]. In this study, the film deposition method for these materials have been developed by electrodeposition. Tbe electrodeposition of rare earth elements is generally considered to be difficult, but in this study, by using Fe chelate as a catalyst, the magnetic films containing Fe and rare earth elements have been successfully deposited, and large magnetostriction are achieved. The TbDyFe films show magnetostriction of ~1000 [1]. In addition, large volume magnetostriction has been observed in these amorphous materials. The magnetostrictive materials are known to have a reverse magnetostriction effect, in which the magnetization of the magnetic material changes when it is subjected to strain. They are known to work as strain sensors based on magnetic measurements. In order to demonstrate the strain sensing, a bi-material cantilever of FeGa/Si with a Si Hall sensor integrated on the support has been developed, as shown in Fig. 1 [2]. The vibration of the cantilever can be detected from the magnetization change using the integrated Hall sensor. On the other hand, magnetostrictive actuators generally require an electromagnet to drive them, making them difficult to miniaturize the system. Therefore, an attempt has been made to drive magnetostrictive thin films by injecting spins into them using the spin Hall effect, giving angular momentum to the spins of magnetic materials and changing the spin fluctuations [4]. It is found that a large strain can be generated by spin injection into the TbDyFe film. The above results show that high-performance magnetostrictive films can be deposited by electrodeposition and can be applied to strain sensors and spin-current driven actuators, and are expected to be applied to the development of novel sensors and actuators [5].References H. Shim, K. Sakamoto, N. Inomata, M. Toda, N. V. Toan and T. Ono, Magnetostrictive Performance of Electrodeposited TbxDy(1−x)Fey Thin Film with Microcantilever Structures, Micromachines 11, 5 (2020) 523.T. Ezura, N. Inomata, T. Ono, Integration of Magnetostrictive Microsensor With Hall Element for Microstructure Resonant Detection, 21st International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers), (2021) 418-421.Mohammad Akita Indianto, Masaya Toa, Takahito Ono, Comprehensive study of magnetostriction-based MEMS magnetic sensor of a FeGa/PZT cantilever, Sensors and Actuators A 331, (2021) 112985.H. Arisawa, H. Shim, S. Daimon, T. Kikkawa, Y. Oikawa, S. Takahashi, T. Ono, E. Saitoh, Observation of spin-current striction in a magnet, Nature Communication 13 (2022) 2400.M. A. Indianto, M. Toda, T. Ono, Development of assembled microchannel resonator as an alternative fabrication method of a microchannel resonator for mass sensing in flowing liquid, Biomicrofluidics 14, (2020) 064111. Figure 1

Design of Voltage Transducer for Digital Signal Processing Development Kit in Implementation of a High Step-up DC-DC Converter

High step-up DC-DC converters are used in many industrial applications Especially, renewable energy systems that have a low output voltage and high output current need DC-DC converters with high voltage gain to meet the requirements of the grid-connected systems for a high output voltage. This study is aimed to design an implementation of hardware of the high step-up DC-DC converter’s measurement board prototype for digital signal processing (DSP) TMS320F28335 development kits. The vital parameter to detect for high step-up application systems is a sampling output voltage. This sample of output voltage is produced by using the voltage transducer (LV 25-P) with hall effect sensor in this research. A signal conditioning circuit includes an operational amplifier featuring unity gain buffer for the protection ADC of the DSP and a low pass filter circuit. Therefore, the requirements of the ADC of EZDSP TMS320F28335 development kit can be met by using this voltage transducer sensor and the signal conditioning circuit.

Development of bismuth metallic hall sensors for the HL-2A tokamak magnetic measurements

100 nm bismuth-based Hall sensors have been developed on the HL-2A tokamak recently. This paper reviews the process of manufacturing a Hall sensor with high sensitivity, including material selection, craft optimization, and platform testing. Magnetron sputtering and SiO2 glass substrate are proposed to reduce the thickness error. The sensitivity of the sensor is obtained by linear fitting, and the calibration accuracy is better than ±1 % when the magnetic field range is greater than 3 mT. The housing and mounting position of the Hall sensor are designed so that they can be compared with the pick-up coils in the upcoming discharge experiment.

Study on Various Position Sensing Technologies in Tractor Hitch Application

Conventionally, In the tractors, hitch position is obtained using a contact-based position sensor, the sensor is attached to the rockshaft mechanically with gears or linkages. In this arrangement, there are incidences of failures when working with heavy implements, as rockshaft is under severe loading conditions which tends to induce cracks or failures in sensor mechanical linkages mounting area. This results in machine downtime and rockshaft repair costs to the customer. These mounting threads in hardened Rockshaft reduce material strength which impacts the lifting capacity. There is associated difficulty at assembly line and further during maintenance for linkage installation and adjustments. Also, over the period, linkages develop a play at joints due to the friction. In the present work, we are sensing the Hitch position with contactless sensor technology. A contactless Hall effect sensor is selected, and proto setup has been designed to measure the hitch position by integrating the sensor and target. The prototype consists of a fixed Sensor and a rotating metal (ferromagnetic) piece placed inside a 3D printed casing. The profile of metal piece is such that when it is rotated about the axis, the distance between Sensor and metal piece changes gradually. This causes different output voltage at different amount of rotation in metal piece. Results from manual bench testing show that the concept is working. The sensor voltage output varies according to the hitch position in the bench setup. A high voltage value when metal piece is nearer to magnet and low value when its farther. A future step is to automate this setup on a tractor to remove errors due to manual rotation. This would be an enabler to analyze the sensor behaviors like hysteresis, repeatability, linearity more accurately.

A wide dynamic range diamond quantum sensor as an electric vehicle battery monitor.

To demonstrate the application capability of the diamond quantum sensor as an electric vehicle (EV) battery monitor, we (i) investigated the measurable current in a real car noise level and (ii) compared the linearity with conventional sensors. Consequently, (i) we could measure a 20 mA current pulse even under an external magnetic field of 80 µT, which is larger than that of 50 µT around the EV battery module in a real car during driving. The 20 mA pulse measurement corresponds to the EV battery state of charge estimation accuracy of 0.2% in the standard driving pattern, which is smaller than the present level of 10%. (ii) The linearity degradation seen in the Hall sensor near the upper limit of the measurement range was not seen in the diamond sensor. Although the Hall sensor and the shunt resistor showed linearity degradation in the current range of several tens of amperes or less, the degradation was smaller for the diamond sensor. The transverse magnetic field effect in the diamond sensor on the linearity was estimated to be less than 0.01% for a several-degree misalignment of the sensor surface to the magnetic field direction and under a 340 A current. This article is part of the Theo Murphy meeting issue 'Diamond for quantum applications'.