A magnetostrictive system in industrial automation doesn't directly convert vibrations into electrical power like a piezoelectric material would. Instead, a magnetostrictive system is used to measure mechanical vibrations or displacements and convert them into electrical signals for monitoring, control, or measurement purposes.
Magnetostriction is a property exhibited by certain materials, notably ferromagnetic ones, where their shape changes in response to an applied magnetic field. When an external mechanical force or vibration is applied to these materials, they experience slight changes in their dimensions due to the magnetostrictive effect. This change in shape results in a change in the magnetic properties of the material, which can be detected and converted into an electrical signal using appropriate sensing techniques.
In an industrial automation context, a magnetostrictive sensor consists of a magnetostrictive material (such as a nickel-based alloy) enclosed within a protective housing. The sensor is typically installed in the equipment or structure that needs to be monitored for mechanical vibrations or displacements. Here's a basic overview of how it works:
Setup: The magnetostrictive sensor is attached to the mechanical component or structure that is subject to vibrations or displacements.
Magnetic Excitation: A magnetic field is generated within the magnetostrictive material using a coil. This coil can be part of the sensor or external to it. The coil generates a pulsed magnetic field that interacts with the magnetostrictive material.
Vibration Detection: When the mechanical component or structure undergoes vibrations or displacements, the magnetostrictive material changes its shape slightly due to the magnetostrictive effect. This alters the magnetic properties of the material in the region of the coil.
Measurement: The changes in the magnetic properties are detected by the coil, inducing an electrical current within it. This electrical current is proportional to the mechanical displacement or vibration being measured.
Signal Processing: The induced electrical signal is then processed by electronic circuits and converted into usable data. This data can be used for various purposes, such as monitoring equipment health, controlling processes, or providing feedback for automation systems.
In essence, the magnetostrictive system acts as a transducer that converts mechanical vibrations or displacements into electrical signals that can be easily measured and processed. However, it's important to note that the primary function of such a system is sensing and measurement, not direct energy conversion like some other technologies (e.g., piezoelectric materials) might achieve.