Abstract: A method of designing a high power factor integrated ferroresonant constant current source includes the steps of providing an input coil disposed about a ferromagnetic core and to be coupled to an AC voltage source. An output coil is to be coupled to a load. A control coil is coupled to a switch for regulating current output of the constant current source. A first capacitor coil is inductively coupled to the output coil and coupled to a capacitor to provide a first resonant sub-circuit having maximum gain, and a second capacitor coil is inductively coupled to the control coil and coupled to a capacitor to provide a second resonant sub-circuit to control resonant gain. A flux density (BPRI) is selected for a portion of the core around the input coils that is substantially lower than the flux density BCAP of a portion of the core around the capacitor coils.

Abstract: A controlled ferroresonant constant current source includes a ferromagnetic core accommodating the below-mentioned inductors. An input coil is to be connected to an alternating voltage source. An output coil is inductively coupled to the input coil, and is to be connected to a load. A control coil is inductively coupled to the output coil, and is to be connected to a switch for regulating the current output of the constant current source. A first capacitor coil is inductively coupled to the output coil, and is to be connected to a capacitor to provide a first resonant sub-circuit having maximum gain. A second capacitor coil is inductively coupled to the control inductor, and is to be connected to the capacitor to provide a second resonant sub-circuit to control resonant gain.

Abstract: A ferroresonant ballast for regulating the current level of gas discharge lamps includes a magnetic core for supporting coil windings. A first or input coil is wound about the magnetic core for supplying a changing input voltage. A second or capacitor coil is wound about the magnetic core and is induced by the first coil to generate an output voltage across an output or resonant capacitor. A third or lamp coil is wound about the magnetic core and coupled to a gas discharge lamp which is regulated at a constant voltage in response to the voltage generated across the output capacitor. The ferroresonant ballast may include a control circuit and inductor that is switchable coupled to the output capacitor for simulating core saturation.

Abstract: A ferroresonant transformer includes a three-legged magnetic core. The core includes a center leg, and first and second flanking legs. Each of the center and flanking legs have respective first and second longitudinal ends. The first flanking leg is positioned at an opposite side of the center leg relative to the second flanking leg. A first end-connecting portion magnetically couples the first ends of the center and flanking legs, and a second end-connecting portion magnetically couples the second ends of the center and flanking legs. The center leg defines a substantially non-magnetic space, such as an air gap, along a magnetic flux path extending along the center leg from the first end-connecting portion to the second end-connecting portion in order to reduce the total harmonic distortion of the ferroresonant transformer.