Abstract: A three-phase current limiter (30) for an alternating current system includes an AC magnetic circuit having at least one AC coil (35R1, 35S1, 35T1) for each phase of a 3-phase AC supply wound on a saturable ferromagnetic core and configured to subject respective AC coils for each phase to a common magnetic flux, and a DC magnetic circuit (34a, 34b) for biasing the AC magnetic circuit into saturation at normal conditions. In use the AC coils are connected in series with a load and during alternate half cycles of the AC supply at least one of the AC coils produces a magnetic field that opposes a magnetic field of the DC magnetic circuit. The AC coils (35R, 35S, 35T) for each phase are configured so that at least one of the AC coils exhibits unbalanced magnetic impedance relative to remaining ones of the AC coils for each phase.

Abstract: A method for magnetically inducing voltages in the secondary windings of a transformer without saturating its core. The method includes (a) applying to a first primary driven winding a first set of voltages, thereby generating (i) a first current in the first primary driven winding, (ii) a first magnetic field having a first quantum of energy, and (iii) a magnetically induced second set of voltages in the first secondary winding; (b) interrupting the first current, thereby causing the first magnetic field to collapse, and (c) not later than interrupting the first current, clamping the first primary driven winding to a third set of voltages, thereby magnetically inducing a fourth set of voltages in the first secondary winding. At least one of the fourth set of voltages is less than at least one of the second set of voltages.

Abstract: An uninterruptable power supply system for producing an AC voltage from at least one of a DC power source or an AC power source includes an input terminal configured to receive an AC voltage from an AC power source, and an inverter operative to produce an AC voltage at an output thereof from a DC power source. A ferroresonant transformer circuit includes a transformer having an input winding, a output winding, and a third winding that forms part of a resonant circuit that produces saturation in the output winding when an AC voltage on the input winding exceeds a predetermined amplitude. A transformer input control circuit is coupled to the input terminal and to the inverter output and is operative to couple at least one of the input terminal and the inverter output to the input winding.

Abstract: The present invention discloses a saturable reactor and a method for decoupling the interwinding capacitance from the frequency limitations of the reactor so that the equivalent electrical circuit of the saturable reactor comprises a variable inductor. The saturable reactor comprises a plurality of physically symmetrical magnetic cores with closed loop magnetic paths and a novel method of wiring a control winding and a RF winding. The present invention additionally discloses a matching network and method for matching the impedances of a RF generator to a load. The matching network comprises a matching transformer and a saturable reactor.

Abstract: In the voltage converter, a current flowing through a primary coil of a voltage transformer is turned on/off by FETs, an AC voltage induced at a secondary coil of voltage transformer is rectified and applied to a choke coil including two coils, a saturable choke coil and a flywheel diode are connected between two coils of the choke coil and the ground, and a saturable reactor is reset in response to the output voltage, whereby the output voltage is adjusted.

Abstract: A power supply for an electronic device such as the control circuitry of a thermostat. The power supply has a current transformer with a primary winding in series with the power line that is connected to the heating source, and a secondary winding coupled to the primary winding through a saturable magnetic core. A thyristor connected across the output terminals of the secondary winding establishes a momentary short-circuit condition when the voltage developed across the secondary winding exceeds a preset level in order to prevent the magnet core of the transformer from saturating.

Abstract: Power conditioning apparatus particularly suited for computer facilities and including non-linear input chokes connectable with line power. These chokes are structured having a center leg configured to define a varying gap having a narrowest flux transfer region located centrally with respect to a surrounding shell structure. The gap configuration expands uniformly outwardly from this narrowest region. The outputs of the input chokes are serially, magnetically coupled through primary windings to pulse saturable reactors of a synthesizing network which includes a capacitor bank and operates to synthesize a sinewave output. The capacitance values of the capacitor bank are selectively distributed between the primary, isolation windings and the pulse saturable secondary or regulator components of the synthesizer network to achieve important improvements in system efficiency.

Abstract: To regulate a supply voltage for a television receiver load circuit, such as the ultor voltage for a high voltage circuit, the primary winding of a transformer is coupled to a source of alternating input voltage for developing an alternating polarity voltage across a secondary winding of the transformer. A saturable reactor includes a magnetizable core with a reactor winding wound around the core. The reactor winding and the transformer secondary winding are conductively coupled to develop an alternating polarity voltage across the reactor winding. The transformer secondary winding is magnetically isolated from the saturable reactor such that the magnetic flux flowing in the reactor core does not link the transformer secondary winding. A capacitor is coupled to the saturable reactor winding for developing a circulating current that aids in magnetically saturating a portion of the reactor core associated with the reactor winding.

Abstract: A self-regulating power supply for a television receiver includes a transformer with a primary winding coupled to a source of input voltage for developing an alternating polarity supply voltage across a secondary winding. The supply voltage is stepped up, rectified and filtered to develop an ultor accelerating potential for the picture tube of the television receiver. A ferroresonant or self-regulating load circuit includes a saturable reactor having a winding coupled to the transformer secondary winding to provide regulation of the supply voltage, and thus, regulation of the ultor accelerating potential. The transformer secondary winding and the saturable reactor winding each comprises two winding sections, with each section having a terminal coupled to a common reference point, such as chassis ground.

Abstract: The primary winding of a high leakage inductance transformer is coupled to a source of alternating input voltage to develop alternating polarity output voltages across tightly coupled secondary windings, including a high voltage winding of the transformer. Various DC supply voltages, including the ultor voltage, are derived from the secondary winding output voltages. To regulate the secondary winding output voltages, a ferroresonant circuit comprising a capacitor and a saturable reactor is coupled as a load circuit to one of the transformer secondary windings. When the saturable reactor magnetically saturates during each half cycle of the alternating polarity output voltage, a circulating current is generated and flows between the saturable reactor and the capacitor.

Abstract: A source of high frequency alternating input voltage is coupled to the primary winding of a high frequency low voltage ferroresonant transformer of a television receiver power supply. A capacitor is coupled across the secondary output winding of the ferroresonant transformer, and generates a circulating current that magnetically saturates the secondary core portion of the transformer to regulate the alternating polarity output voltage developed across the secondary output winding. A step-up high voltage transformer includes a primary winding and a high voltage secondary winding tightly coupled to the step-up transformer primary winding. The regulated alternating polarity output voltage developed by the low voltage ferroresonant transformer is coupled to the primary winding of the step-up high voltage transformer without prior DC rectification of the ferroresonant transformer output voltage.

Abstract: A current isolator circuit generates an electrically isolated output current which is related to an input current. The current isolator includes a magnetically saturable transformer having a core and first, second, and third windings. The input current flows through the first winding, and the output current flows through the second winding. The third winding is driven by a periodic drive signal, which alternately drives the transformer between first and second magnetically saturated states. When a change in the input current occurs, the magnetizing current in the third winding changes, thereby causing a change in the time required to drive the transformer from the first to the second magnetically saturated state, and an opposite change in the time required to drive the transformer from the second to the first magnetically saturated state. The difference in saturation times is sensed and is used in controlling the magnitude of the output current flowing through the second winding.