using combinations of saturated and unsaturated inductive devices, e.g. combined with resonant circuit

Full Title

Non-retroactive systems for regulating electric variables by using an uncontrolled element, or an uncontrolled combination of elements, such element or such combination having self-regulating properties > Regulating voltage or current > wherein the variable is AC > using combinations of saturated and unsaturated inductive devices, e.g. combined with resonant circuit