Working principle of current Hall sensor

- Mar 01, 2021-

The Hall principle current sensor is based on the two basic principles of Hall magnetic balance principle (closed loop) and Hall direct measurement (open loop).

The principle of the open loop current sensor: the magnetic flux generated by the primary current IP is concentrated in the magnetic circuit by the high-quality magnetic core, the Hall element is fixed in a small air gap, and the magnetic flux is linearly detected. After the Hall voltage is processed by a special circuit, the secondary side outputs the follow-up output voltage consistent with the primary side waveform, and this voltage can accurately reflect the change of the primary side current. The Hall current sensor can measure various types of current, from direct current to alternating current of several tens of kilohertz, and its working principle is mainly the Hall effect. When the primary wire passes through the current sensor, ① the primary current IP will generate magnetic lines of force, ② the primary magnetic lines of force are concentrated around the core, ③ the Hall electrode built into the core air gap can generate a size proportional to the primary magnetic line of force With a voltage of only a few millivolts, the electronic circuit can transform this tiny signal into the secondary current IS, and the following relationship exists.