Ferroresonant battery charger with constant current finish rate

Abstract

Feedback and associated electronic control circuitry are eliminated in a battery charger incorporating a ferroresonant transformer for providing a constant current to a charging battery as typically required such as during the final hours of charging. The ferroresonant transformer includes an input primary winding, an output secondary winding, and a regulating winding in combination with a tuned reactor for maintaining transformer minimum output current constant, the precise value of which can be established by transformer and tuned reactor values as well as the value of a resonating capacitor. As the battery approaches full charge and the charger's current approaches minimum value, the charger's output voltage automatically is adjusted to maintain the selected current. The battery's state of charge which dictates the load on the charger changes the amount of energy flowing in the tuned reactor and regulating winding. As more energy is shifted to the regulating winding, the output voltage rises and vice versa. This change in voltage regulates the output current to the battery.

Dependencies are inferred from the claim text.