Difference:
The Hall device is a magnetic sensor. They can be used to detect magnetic fields and their changes, and can be used in various magnetic field-related occasions. Hall devices work based on the Hall effect. ?Hall devices have many advantages. They have a solid structure, small size, light weight, long life, easy installation, low power consumption, high frequency (up to 1MHZ), vibration resistance, and are not afraid of dust, oil, water vapor and salt spray, etc. contamination or corrosion.
Principle:
The Hall type uses the Hall model of the motor to determine the current motor movement state, and then the controller controls the controller based on the signals collected by the Hall. Three-phase output is used to power the motor so that the motor can continue to work normally.
The non-Hall type means that the motor does not have a Hall sensor. The controller determines the current motion state of the motor through current collection, and then controls the controller output to supply power to the motor so that the motor can work at full capacity.
Function:
The Hall-type motor and controller are stable during use, with large torque at startup and no abnormal noise.
Due to technical problems when using Hall-free motors and controllers, they are currently not very stable, especially in the initial stage, with poor stability and insufficient power.
Hall sensors are used in many places in electric bicycles, such as speed control handles, brake levers, and brushless motors.
Extended information:
The Hall sensor is a magnetic field sensor based on the Hall effect. The Hall effect is a type of magnetoelectric effect. This phenomenon was discovered by A.H. Hall (1855-1938) in 1879 while studying the conductive mechanism of metals. Later, it was discovered that semiconductors, conductive fluids, etc. also have this effect.
The Hall effect of semiconductors is much stronger than that of metals. Various Hall elements made using this phenomenon are widely used in industrial automation technology, detection technology, and information processing. The Hall effect is a basic method for studying the properties of semiconductor materials. The Hall coefficient measured through the Hall effect experiment can determine important parameters such as the conductivity type, carrier concentration, and carrier mobility of the semiconductor material.
According to the principle of the Hall effect, the size of the Hall potential depends on: Rh is the Hall constant, which is related to the semiconductor material; I is the bias current of the Hall element; B is the magnetic field strength; d is the thickness of the semiconductor material.
For a given Hall device, when the bias current ?I? is fixed, UH will completely depend on the measured magnetic field strength B. A Hall element generally has four lead-out terminals, two of which are the input terminals of the bias current ?I? of the Hall element, and the other two are the output terminals of the Hall voltage. If the two output terminals form an external loop, Hall current will be generated.
Generally speaking, the bias current setting is usually given by an external reference voltage source; if the accuracy requirements are high, the reference voltage source is replaced by a constant current source. In order to achieve high sensitivity, the sensing surface of some Hall elements is equipped with a coating alloy with high magnetic permeability; the Hall potential of this type of sensor is relatively large, but it saturates around 0.05T, and is only suitable for low-quantity, Used in small range.
A controlled current I is passed through both ends of the semiconductor sheet, and a uniform magnetic field with a magnetic induction intensity B is applied in the vertical direction of the sheet. Then, in the direction perpendicular to the current and magnetic field, an electric potential difference of UH will be generated. Hall voltage.
There is a Hall semiconductor chip in the magnetic field, and a constant current I passes through the chip from A to B. Under the action of Lorentz force, the electron flow of I is deflected to one side when passing through the Hall semiconductor, causing the film to generate a potential difference in the CD direction, which is the so-called Hall voltage.
The Hall voltage changes with the change of the magnetic field strength. The stronger the magnetic field, the higher the voltage. The weaker the magnetic field, the lower the voltage. The Hall voltage value is very small, usually only a few millivolts, but often The amplifier in the integrated circuit amplifies the voltage enough to output a stronger signal. If the Hall integrated circuit is used as a sensor, mechanical methods are needed to change the magnetic induction intensity.
A rotating impeller is used as a switch to control the magnetic flux. When the impeller blades are in the air gap between the magnet and the Hall integrated circuit, the magnetic field deviates from the integrated chip and the Hall voltage disappears. In this way, the change in the output voltage of the Hall integrated circuit can indicate a certain position of the impeller drive shaft. Using this working principle, the Hall integrated circuit chip can be used as an ignition timing sensor. Hall effect sensors are passive sensors that require an external power supply to work. This feature enables them to detect low-speed operations.
Reference: Baidu Encyclopedia-Hall Sensor