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Servo Feedback Devices and Motor Sensors
Published in Wei Tong, Mechanical Design and Manufacturing of Electric Motors, 2022
The Hall effect provides information regarding the type of magnetic pole and magnitude of the magnetic field. Sensors based on the Hall effect principle are called Hall effect sensors. A Hall effect sensor employs a magnetic phased array sensor passing through a magnetic field to produce a signal that is then interpolated to resolution. Though Hall effect sensors essentially are magnetic field sensors, they can be applied in many other types of applications for measuring position, velocity, force, current, pressure, temperature, etc. Among the various sensing technologies, Hall effect sensors have long been used in numerous industrial segments for their small sizes, ruggedness, ease-of-use, and relatively low cost [8.31]. They can operate at high frequencies and are not affected by environmental contaminants. Compared with other motion feedback devices, however, Hall effect sensors feature low sensitivity, low breakdown voltage, and susceptibility to temperature; all limit sensors to use in high voltage power systems. In addition, Hall effect sensors are less precise. Therefore, Hall effect sensors provide the simplest and least expensive solution for applications that do not require precise speed or position controls.
Power Converters Used in Body Systems
Published in Dorin O. Neacşu, Automotive Power Systems, 2020
The Hall effect was first noted by Dr. E. H. Hall, hence the name. If a certain type of crystal is carrying a current in a transverse magnetic field, then a voltage will be produced at right angles to the supply current (Figure 5.20). The magnitude of the voltage is proportional to the supply current and to the magnetic field strength. The Hall based position sensor is typically made from semiconductors such as silicon and germanium. The Hall-effect sensors work by measuring the Hall voltage across two of their faces when you place them in a magnetic field. Some Hall sensors are packaged into convenient integrated circuit chips with control circuitry and can be plugged directly into bigger electronic circuits.
Digital Transducers
Published in Clarence W. de Silva, Sensor Systems, 2016
The longitudinal arrangement of a proximity sensor, in which the moving element approaches the sensor head-on, is not suitable when there is the danger of overshooting the target, since it will damage the sensor. A more desirable configuration is the lateral arrangement, in which the moving member slides by the sensing face of the sensor. The sensitivity will be lower, however, with this lateral arrangement. The relationship between the output voltage vo and the distance x of a Hall-effect sensor, measured from the moving member, is nonlinear. Linear Hall-effect sensors use calibration to linearize their output.
A novel home automation distributed server management system using Internet of Things
Published in International Journal of Ambient Energy, 2022
P. Manojkumar, M. Suresh, Alim Al Ayub Ahmed, Hitesh Panchal, Christopher Asir Rajan, A. Dheepanchakkravarthy, A. Geetha, B. Gunapriya, Suman Mann, Kishor Kumar Sadasivuni
The Hall Effect sensor was preferred here for sensing load current because of physical isolation from the phase wire. To connect the current sensor, there is no necessity to damage the load supply wire because it senses the magnetic field produced by the wire. The amount of magnetic flux produced is directly proportional to the current flow. It is easy to install in the existing domestic wiring and there is no fire hazard and circuit break in sensor failure conditions due to the physical isolation. The output of the Hall Effect sensor is voltage that is directional proportional to the magnetic flux. The output of both temperature and Hall Effect sensor are in an analogue form. An external Analogue to Digital Converter is used to interface with Raspberry pi, because there is no internal or in-built ADC in the Raspberry pi. Here ADS1115 ADC is used to design the home automation system. It is a high precision 16-bit ADC which gives a maximum of 860 samples per second. It has four single-ended inputs and a programmable input gain amplifier for small signal conversion. The standard I2C mode is used for communication between the Raspberry pi and a 7-bit ADC addressing at 100 kilo-bits per second data rate. Relays are designed for switching the load because it has high load current switching capability. The load switching relay cannot be directly connected to the Raspberry pi GPIOs because the GPIOs can deliver only 20 mA of current at 3.3 V. An isolated transistor switching relay driver circuit is used to drive the relay. The isolation is necessary to protect the Raspberry pi from accidental high voltage back EMF from relay circuitry. To monitor the current drain using load, the Hall Effect sensor is connected to each load supply line. The status and power consumption of the load can be calculated based on the current drain.
Solar PV Combined Efficient Torque Control of BLDC Motor Using Salp Swarm Optimization
Published in Electric Power Components and Systems, 2023
G. Jayabaskaran, S. Suresh, B. Gopinath, M. Geetha
Additionally, the need for sensors to identify the rotor position with Back EMF estimation. To use Hall Effect sensors for this purpose. Hall Effect sensors are contactless sensors that use a magnetic field to detect the position of the rotor and generate an electrical signal proportional to the magnetic field. This signal can then be used to estimate the Back EMF of the rotor, allowing us to accurately identify its position. It is believed that using Hall Effect sensors will be the most reliable and efficient way to identify the rotor position.
A new self-calibration method for electronic current transformers
Published in Journal of the Chinese Institute of Engineers, 2018
Kun-Long Chen, Guan-Jie Huang, Nanming Chen, Wei-Jen Lee
Both quiescent output voltage and sensitivity of Hall-effect sensors are influenced by ambient temperature. Hence, the accuracy of the selected ECT based on Hall-effect sensors is also affected by the ambient temperature. This study proposes a self-calibration method which is aimed to automatically adjust (1) quiescent output voltage of Hall-effect sensors; (2) sensitivity for current measurement.