Air core transformers, as the name itself suggests, are transformers that have air in their core, unlike other transformers that have some or the other sort of metal around which wires are wound. These are primary transformers that are used in various types of electronic radio and communication devices. The best usage is in small electronic applications like radio transmission.
How do air core transformers work?
The basic functioning and working of an air core transformer is based on the induction between two magnetically linked coils or windings – the primary and the secondary. The coils are generally constructed from insulated copper wire, which are wound on a non-magnetizing surface like a cardboard or plastic tube, because air core transformers do not contain any magnetic cores (as we’ve mentioned above). This is why unlike other transformers that create flux by utilizing their cores, air core transformers create flux using their windings and the air passing through them. Such mechanism results in zero dissipation of signal quality, zero distortion, and zero noise during operation. As a result, there is also no loss in terms of hysteresis and eddy currents.
Why are air core transformers preferred?
With a few benefits of air core transformers listed above, such as zero distortion, zero noise, zero signal quality dissipation, and zero losses, people are looking forward to using them. But, this is not all. There are a lot many more benefits that come with air core transformers. For instance, the absence of a solid metallic core makes air core transformers light in weight and small sized, which makes them an ideal option to be used in portable electronic devices.
Types of air core transformers
There are two main types of air core transformers used in electronic applications, namely cylindrical air core transformers and toroidal air core transformers.
Cylindrical air core transformers – As the name itself suggests, these are transformers having insulated copper wires wound on a cylindrical hollow non-metallic structure, with the primary copper coils being tapped at certain places, and the secondary winding being wound across the taps.
Toroidal air core transformers – These are transformers having insulated copper wires wound around a non-metallic ring-shaped structure, with each coil winding utilized separately. This ensures minimal effect of stray couplings, and a benefit for applications consisting of high frequencies.
Maintaining air core transformers
Just buying any air core transformer is not enough. You need to ensure that you are buying from a reputed and experienced manufacturer, such that every aspect of the transformer in terms of its performance and operation can be taken care of. For example, in cylindrical air core transformers, a guard winding can be wound around the primary winding to allow for effective impedance matching. This guard winding can be connected to antenna receivers to improve the transformer’s operation. Another way to improve the transformer’s performance is to connect a capacitor to the winding, such that the winding maintains a constant resonance of the tuning circuit.
Miracle Electronics is one such reputed transformer manufacturer in India who can help design the best quality transformer for your particular application.
