What Is Ferroresonant?
A ferroresonant transformer is a non-linear transformer that is designed to provide passive voltage regulation, using magnetics only; that is, without any complex feedback circuits to monitor and adjust the output voltage level. It is designed to operate within a preset regulation band; typically set anywhere from 1%-4%. A non-linear transformer differs from a linear transformer in that the output voltage will not deviate outside of this regulation band, regardless of what happens on the input. The output of a linear transformer, on the other hand, is as the term implies, directly proportional to the input. That is, whatever happens on the input will directly affect the output. Ferroresonant transformers also have the unique characteristic of being able to store energy for up to 1/2 cycle because of its “tank circuit” design. When combined with an inverter and static transfer switch in a UPS application, this characteristic provides “ride-through” capability to allow for a completely u
