A toroidal coil inductor, also known as a toroidal inductor or magnetic ring inductor, is a type of wound inductor electronic component with a toroidal magnetic core as its core component. Its magnetic core is typically made of materials such as ferrite or iron powder, and it features high Q value, low electromagnetic interference, and low leakage flux in a closed magnetic circuit. It is mainly used in high-frequency circuits, power conversion and filtering, electromagnetic interference suppression, and vehicle detection systems.
Its inductance can be calculated using the formula L=AL×N². In vehicle detection, it forms an LC oscillator with a capacitor; changes in inductance are converted into frequency shifts to achieve vehicle detection. Relevant national standards specify its inductance range. Its winding process largely relies on manual labor, which is one of the factors limiting production efficiency.
