Toroidal transformers

InduComp’s toroidal cores have low specific core and eddy current losses. The low no-load losses allow customers to manufacture energy-efficient devices. The dimensions of the toroidal cores can be flexibly adapted to customer requirements. Depending on the transmitted power, a certain volume is needed, but the available space in the customer’s device can be utilized. The transformer can be mounted by filling the interior with polyurethane resin, allowing the transformer to be fixed with a screw through the central hole. Special toroidal winding machines distribute the turns evenly over the entire perimeter of the core. This winding technology provides very low magnetic leakage, so adjacent electrical circuits are less affected by magnetic noise. Due to this construction, toroidal transformers also have good magnetic coupling between the primary and secondary windings, and the low leakage inductance can be ignored when calculating load voltages. However, in the event of a short circuit, relatively large short-circuit currents can be observed, making protection with fuses generally unavoidable. Additionally, self-resetting thermal cut-offs (normally closed NC switches) or thermal fuses can be integrated as thermal protection.

Due to the described construction, high inrush currents can also occur when starting the transformer. Particularly high-power transformers with low winding resistance can create large inrush current peaks in the first periods until they stabilize.