The working principle of the inductive pressure sensor is that due to the different magnetic materials and permeability, when the pressure acts on the diaphragm, the size of the air gap changes, and the change of the air gap affects the change of the coil inductance.The processing circuit can convert the change of this inductance into a corresponding signal output, so as to achieve the purpose of measuring the pressure.This kind of pressure sensor can be divided into two types according to the change of magnetic circuit: variable reluctance and variable permeability.The advantages of inductive pressure sensors are high sensitivity and large measurement range; the disadvantage is that they cannot be used in high-frequency dynamic environments.
The main components of the variable reluctance pressure sensor are the iron core and the diaphragm.The air gap between them forms a magnetic circuit.When there is pressure, the size of the air gap changes, that is, the magnetoresistance changes.If a certain voltage is applied to the iron core coil, the current will change with the change of the air gap, thereby measuring the pressure.
In the case of high magnetic flux density, the magnetic permeability of ferromagnetic materials is unstable. In this case, a variable magnetic permeability pressure sensor can be used to measure.The variable permeability pressure sensor replaces the iron core with a movable magnetic element. The change of pressure causes the movement of the magnetic element, so that the permeability changes, and the pressure value is obtained.
Post time: Apr-13-2022