Abstract: In accordance with an embodiment, a power supply circuit includes: a first transistor device comprising a first gate associated with a first transconductance and a second gate associated with a transconductance greater than the first transconductance; and a second transistor device including a third gate associated with a second transconductance and a fourth gate associated with a transconductance greater than the second transconductance. The second transistor device is configured to supply power to at least one load, the first and the third gates are controlled by a closed regulation loop, and the second and the fourth gates are controlled by a sampled reference voltage.

Abstract: An example controller includes: an absolute value circuit having a voltage output and first and second power inputs, the first and second power inputs adapted to be coupled to an alternating current (AC) power source, and a comparator having a comparator output and first and second comparator inputs, the first comparator input coupled to the voltage output, the second comparator input adapted to be coupled to an output terminal of a power factor correction (PFC) circuit, and the comparator output adapted to be coupled to a control input of the PFC circuit.

Abstract: This power conversion device includes: a base; a control substrate; a first rectification element; a second rectification element; a smoothing reactor; an output filter circuit portion; a first main circuit wire; a second main circuit wire; and smoothing capacitors. As seen in a direction perpendicular to a surface of the control substrate, at least some of the smoothing capacitors and a target region obtained by combining a region in which the first rectification element is disposed, a region in which the second rectification element is disposed, and a region between the first rectification element and the second rectification element, overlap with each other, and a low-potential-side connection point of each smoothing capacitor connected to the second main circuit wire, is disposed so as to overlap with the control substrate and a region obtained by extending the target region in a specific direction and a direction opposite to the specific direction.

Abstract: A power supply device may include a connector configured to electrically couple the power supply device to a conductor of the underground power lines; a voltage divider configured to receive an input voltage from the conductor, the voltage divider comprising a capacitor and divider voltage control electronics in series with the capacitor; and, a surge resistor in series with the capacitor and configured to provide impulse protection from surge events. The divider voltage control electronics may be configured to regulate an output voltage of the voltage divider to support variable loads on the voltage divider.

Abstract: A circuit and method provide improved trimming of a DCR sensing circuit where a sensing element is sensitive to self-heating or having a large tolerance. The circuit includes a resistive divider circuit coupled to a sensing element. The resistive divider circuit includes a trim resistor and two test points. Prior to trimming the trim resistor, an actual resistance of the sensing element is determined. A target voltage across the trim resistor to be trimmed is calculated according to the determined sensing element resistance and a known small trim current that is to be injected into the circuit during the trimming process. This injected trim current has a low current value so there is no self-heating of the sensing element. Then, the trim resistor is trimmed while injecting this small trim current into the resistive divider circuit and the voltage across the trim resistor is monitored.

Abstract: A control system for controlling a DC-DC voltage converter circuit is provided. An output voltage controller outputs a DC-DC voltage converter control voltage to an input control terminal to increase a switching duty cycle within the DC-DC voltage converter circuit when the low voltage is less than an output reference voltage. An input voltage controller reduces the DC-DC voltage converter control voltage at the input control terminal of the DC-DC voltage converter circuit when a high voltage is less than an input reference voltage to reduce the switching duty cycle within the DC-DC voltage converter circuit.

Abstract: A converter comprises an input stage coupled to a power source, wherein the input stage comprises a plurality of power switches, a resonant tank coupled to the plurality of power switches, a transformer coupled to the resonant tank, an output stage coupled to the transformer, an efficiency point tracking indicator coupled to the converter, a detector coupled to the efficiency point tracking indicator and a control circuit configured to receive an efficiency point tracking signal from the detector and adjust a switching frequency of the power switches based upon the efficiency point tracking signal.

Abstract: An induction heating apparatus is capable of stop heating without excessively boosting output voltages of a booster circuit and a power factor correction circuit. The induction heating apparatus includes a boosting function unit, an inverter circuit, and a booster circuit controller. The boosting function unit includes a power factor correction circuit and a booster circuit, and boosts an input direct-current power to a direct-current voltage having a peak value larger than the peak value of the input direct-current power by turning on/off a switching element. The inverter circuit includes a heating coil, and inputs the direct-current voltage output by the boosting function unit to generate a high frequency current in the heating coil by turning on or off a different switching element. The booster circuit controller stops a boosting operation of the boosting function unit without a prescribed delay from the stop of an operation of the inverter circuit.

Abstract: A power supply with a piezoelectric transformer is provided. A method for power conversion is also provided. The power supply includes a piezoelectric transformer and an oscillator circuit connected to the piezoelectric transformer. The oscillator circuit controls a sinusoidal voltage waveform at an input of the piezoelectric transformer to drive the piezoelectric transformer.

Abstract: Energy management of an electronic device using multiple electric power sources. The electric power sources may include a parasitic electric power source, a rechargeable electric power source, an intermittent electric power source, and a continuous electric power source. The electronic device further may include a power supply for receiving the electric power from the source(s) and supplying electric power to the various components of the electronic device that require power. The electronic device may include a source selector for controlling which power source supplies electric power to the power supply. Energy management of the electronic device may be configured to use a permanently exhaustible power source such as a battery only when other power sources are unavailable.

Abstract: The present invention relates to an electrical device for charging accumulator means (5), said electrical device comprising: a motor (6) connected to an external mains (11); an inverter (2) connected to the phases of said motor (6); and switching means (4) integrated into the inverter (2), said switching means (4) being configured to permit said motor (6) to be supplied and to permit the accumulator means (5) to be charged by the inverter (2). According to the invention, said electrical device further includes, for each phase of said motor (6), an RLC low-pass filter (18) connected, on the one hand, to the mid-point (16) of the phase of said motor (6) and, on the other hand, to ground.

Abstract: A contactless charging system is made up of an electronic device and a contactless charger 200 that recharges the electronic device in a contactless manner. The electronic device transmits a full charge command indicating completion of charge. Upon receipt of the full charge command, the contactless charger shifts to a charge stop state in which charge of the electronic device is not performed. In the charge stop state, the contactless charger generates a load check signal for checking whether or not the electronic device is placed in the contactless charger in a rechargeable state, and transmits the signal. Further, the contactless charger also generates a charge restart check command for checking whether or not the electronic device requests recharge in a charge stop state, and transmits the command.

Abstract: A switch controller is disclosed that adaptively controls the operating frequency of a switching power converter in order to improve one-time load response and repetitive dynamic load responses. During a transition from a high load to low load condition, the switch controller clamps the operating frequency of the switching power converter at an intermediate frequency for a period of time before allowing the operating frequency to return to a frequency associated with the low load condition. The clamped frequency is higher than the frequency associated with the low load condition thereby allowing improved response to a subsequent load change to a high load condition. Thus, the system improves dynamic load response without compromising no-load power consumption.

Abstract: The invention discloses a method and system to detect zero current conditions in a buck inductor by monitoring the voltage across the buck inductor. Once zero current and voltage conditions are present, an inverter circuit changes the operational state, i.e. conducting or non-conducting, of the switching transistors driving the lamps to reduce power loss associated with changing the operational state of switching transistors when under a load.

Abstract: A power factor correction device includes a rectifier for converting an AC input voltage into a DC input voltage, an output module for generating and outputting a DC output voltage, an intermediate inductor coupled between the rectifier and the output module, a power switch for controlling an inductor current of the intermediate inductor and generating a source voltage, a reset module for generating a reset instruction according to the DC input voltage, the DC output voltage and the source voltage, an SR flip-flop for outputting a latch result according to a set instruction and the reset instruction, and a set module for generating the set instruction in response to variation of the intermediate inductor or variation of the latch result.

Abstract: A power supply produces one or more conditioned and scaled output voltages with low noise. The power supply has various components to produce a plurality of higher output voltages from a plurality of taps of a multiplier or multiple isolated outputs. Components include an internal reference voltage circuit or an external voltage that generates a reference voltage and a sine wave power oscillator circuit and resonant circuit that generates an alternating current and voltage. The power supply has a controlled current source circuit connected to the sine wave power oscillator circuit for regulating the power level to the sine wave power oscillator. A control amplifier circuit controls the current level to the controlled current source circuit based on the error between the sampled output and the reference voltage. The resonant transform connected to the sine wave power oscillator circuit generates one or more scaled output voltages on one or more secondary windings.

Abstract: An electronic ballast including a rectifying circuit to provide a signal representative of the current signal associated with a buck inductor, a monitoring circuit to provide a monitoring circuit signal when the signal representative of the buck inductor is within a specified range, and a comparing circuit coupled to the rectifying circuit and the monitoring circuit and operable to alter the output of the power converter circuit driving the lamps in response to comparisons between the signals from the rectifying circuit and the monitoring circuit to control power conditions in the ballasts.

Abstract: Provided is a flux regulation method for use in a power converter, wherein the method is carried out by a flux bias controller. The flux bias controller includes a current detector which is configured to detect the primary current of the transformer of the power converter in a predetermined switching cycle, a DC bias processor which is configured to obtain the duty ratio control signal according to the sampled primary current outputted from the current detector for a switching cycle later than the predetermined switching cycle, and a PWM controller which is configured to generate driving signals to control the on/off operations of the switching circuit of the power converter according to the duty ratio control signal, thereby suppressing the DC bias of the transformer by regulating the duty ratio of the switch circuit.

Abstract: The invention provides a power converter and method for controlling same, comprising a plurality of switch elements, an inductive reactor, and at least two ports for the movement of electrical energy. Any energy-moving port may be made unipolar, bidirectional, bipolar, or bidirectionally bipolar. Ports may be equipped with sensing circuitry to allow the converter output to be controlled responsively to an input signal. The invention may be configured to be used in many ways, for example, as a power-supply, as an amplifier, or as a frequency converter. The invention may comprise energy predictive calculating means to obtain excellent transient response to line and load variations. The invention may also include a switch to create a low impedance path around the inductor to allow current to recirculate through the inductor when it is not needed at any of the ports.

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 superconducting magnetic energy storage (SMES) device (1) comprising a first coil (2) made of superconducting material, cooling means (3) for cooling the first coil to superconducting temperatures, a second coil (4) inductively coupled to the first coil (2) for inputting energy to, and/or outputting energy from, the first coil (2), and switching means (5) for switching the first coil (2) between a superconducting condition and a non-superconducting condition. The first coil (2) is arranged as a closed loop electric circuit having no connecting means mechanically connected to it for inputting or outputting energy. The switching means (5) comprises a third coil for the application or removal of a magnetic field for switching the first coil (2) between its non-superconducting and superconducting conditions. The invention also relates to a method of inputting energy to and/or outputting energy from the first coil (2) and to a power supply system.

Abstract: For use in a power converter having an inverter coupled to an output rectifier, a post-regulator, a method of operating the same and a power converter incorporating the post-regulator or the method. In one embodiment: (1) a switching circuit, having at least one controllable switch and coupled an output of the power converter, that receives an output voltage from the power converter and produces a phase-shifted waveform therefrom and (2) a transformer, having a primary winding coupled to the switching circuit and a secondary winding coupled to the rectifier, that delivers the phase-shifted waveform to the rectifier to regulate the power converter, thereby allowing the inverter to be unregulated.

Abstract: The blocking time maintenance circuit is applied to a resonant-transition ZVS power converter having saturable core reactors to induce a current in the primary of the transformer which enables ZVS. The circuit includes a peak detector for producing a signal having a magnitude proportional to an input voltage. A biasing mechanism, comprising a current source, is provided in order reset the saturable core reactors in a controlled manner. A control mechanism is connected to the peak detector and the current source in order to generate a reset current, the magnitude of which is correlated to the input voltage. In this manner, the volt-time product of the saturable reactors is varied, thereby maintaining the blocking time relatively constant over a wide range of input voltages and ensuring that the output voltage does not fall out of regulation.

Abstract: A system having reduced quiescent current drawn from a power supply. The system includes a device having a status. Moreover, the system includes a microcontroller, having an active and a sleep mode of operation, for polling the status of the device during the active mode, initiating a function in response to a change in the status during the active mode, and for conserving quiescent current drawn from the power supply during the sleep mode. The microcontroller generates an output signal at a first voltage level during the active mode and generates the output signal at a second voltage level during the sleep mode. The microcontroller, additionally, includes a sensor for switching the microcontroller from the sleep mode to the active mode. Furthermore system includes a storage device for charging to the first voltage level during the active mode, and for discharging to a third voltage level during the sleep mode for triggering the sensor to switch from the sleep mode to the active mode.

Abstract: A self-excitation type switch power supply unit with overcurrent protection. For adopting a simple and reliable current negative feedback protective circuit to coordinate with a complementary bridge circuit, a positive feedback circuit without DC biasing capacitive coupling, an oscillation-starting circuit of the AC power supply, etc., so that the self-excitation type switch power supply can become a practical power supply unit with simple circuitry, small size and low cost.

Abstract: A magnetically variable transformer having primary and secondary windings wound on a magnetic core wherein the transformer core with associated windings is placed in close proximity to an independently wound control coil. The control coil is positioned in one configuration on a focusing armature whose poles straddle the transformer core at positions on opposing sides. In a second configuration the transformer core is placed within the bore of the control coil and an optional focusing armature concentrates the magnetic field at the poles. Application of a control current forms poles at the control coil extremities and causes a change in permeability of the transformer core thereby altering the power output of the transformer inversely to the magnitude of the control current. The magnetically variable transformer controls a D.C. to A.C. inverter circuit which is useful in supplying power to a fluorescent lamp and other A.C. receptive loads. Additionally, a derived D.C.

Abstract: An LC resonant circuit. The resonant circuit includes a resonant capacitor and a transformer. The transformer comprises a magnetic core having a primary winding, secondary winding and control winding wound on the core. The primary winding is loosely coupled with the secondary winding. The resonant capacitor of the circuit is connected in series with the primary winding of the transformer. The control winding saturates the core in response to the application of direct current thereto to control the output of the resonant circuit.

Abstract: A superconductive system for receiving electromagnetic energy from an outside source, storing electromagnetic energy in two interacting forms of DC and AC electric current, and delivering electromagnetic energy to an outside load wherein the electromagnetic energy is charged into and discharged from the superconductive storing system exclusively via inductive coupling links. The electromagnetic energy is stored in the form of DC current in high-capacity superconductive coils with each coil connected into a superconductive permanent close loop circuit. The energy is then used to support electromagnetic oscillation in a superconductive oscillating circuit wherein it is stored in low capacity superconductive coils in the form of AC current. The superconducting oscillating circuit is then used to provide power to an outside source.

Abstract: A superconducting magnetic energy storage system for applying power to a load includes a superconducting magnet, the inductor of which is supplied with current via a source which may be preset to a desired value of current, and wherein a feedback loop responsive to a sensed current adjusts the source to provide the desired current. Energy from the superconducting magnet is transferred via a series of pulses of current from the magnet to a first capacitor for charging the capacitor to a desired voltage greater than the voltage at the superconducting magnet. A further transfer of energy, via a series of pulses of current, results in a charging of a second capacitor to a voltage lower than the voltage of the first capacitor. The second capacitor feeds the load.

Abstract: A detection circuit for use in an electrical power converter having at least one negative output rail, for detecting the voltage of the negative output rail and for converting the voltage to a positive output voltage. The detection circuit includes an input port for receiving the negative output rail voltage from an electrical power converter, an output port, a ground reference potential, a node having a voltage that is positive with respect to the ground reference potential, and a circuit for generating a measurement current from the node to the ground reference potential. The value of this measurement current is a function of the negative output rail voltage received at the input port. A circuit is further provided for generating an output voltage at the output port that is positive with respect to said ground reference potential and whose value is a function of said measurement current.

Abstract: A power source apparatus includes a transformer having a plurality of paired winding portions of primary and secondary windings wound around cores divided by a gap, a driver, connected to the primary winding of the paired winding portion, for switching energization of the primary winding of the transformer to generate a secondary winding voltage, and a selector for selectively driving one of the plurality of paired winding portions.

Abstract: In an inverter-type fluorescent lamp ballast, the inverter is powered from an ordinary electric utility power line by way of a rectifier means providing to the inverter a DC voltage having magnitude variations of about plus/minus 30% occurring at twice the frequency of the power line voltage. The inverter's output is a squarewave voltage of frequency averaging about 30 kHz and with amplitude modulations of about plus/minus 30%; which squarewave voltage is applied to a series-tuned L-C circuit. The fluorescent lamp is connected in parallel with the tank capacitor of this L-C circuit, thereby being provided with a current of magnitude proportional to the magnitude of the squarewave voltage. Within a significant range, the magnitude of the lamp current is a sensitive function of the frequency of the squarewave voltage; which frequency is modulated in such a way as to compensate for the variations in lamp current that would otherwise result from the amplitude modulation on the squarewave voltage.

Abstract: In a magnetron drive apparatus a high frequency voltage converted and outputted by a frequency converter is inputted to a primary winding of a transformer and a high voltage power outputted from a secondary winding of the transformer is rectified and supplied to an anode of the magnetron and a power outputted from a heater winding of the transformer is supplied to a heater of the magnetron. The magnetron drive apparatus comprises a magnetic flux leakage device disposed in a magnetic path formed by the primary and secondary windings of the transformer and increasing a leakage magnetic flux in the magnetic path; and a device for winding the secondary winding and the heater winding therearound in a position opposite the primary winding with the magnetic flux leakage device arranged therebetween.

Abstract: An inductive component for universal use in any electrical/electronic circuits, whose coefficient of self-induction (L) is independent of the signal, is constant, electrically controllable and can be varied significantly. The component (10) comprises two mutually independent, identical ring-shaped and self-contained ferro-magnetic cores (11, 12) which individually carry the partial windings (15.1, 15.2) of an induction winding (15) and jointly carry a control winding (17). The direction of coiling of the windings (15.1, 15.2, 17) is such that the magnetic fields produced by currents through the windings are mutually weakened, but in the other core (12) they are reinforced. The component (10) is connected via its induction winding (15) to a controlled circuit (25), and via its control winding (17) to a controlling circuit (27), or forms with its windings (15, 17) an element of this circuit (25, 27).

Abstract: A magnetic amplifier including a magnetic core having a primary leg, a secondary leg, and a control leg. A primary winding is wound about the primary leg of the magnetic core for generating a non-saturating magnetic AC flux in the magnetic core, and a secondary winding is wound about the secondary leg of the magnetic core. A control winding for conducting DC current is wound about the control leg of the magnetic core for controlling as a function of the DC current, without saturating the magnetic core, the reluctance of the control leg relative to the reluctance of the secondary leg. By controlling the relative reluctance, the amount of magnetic AC flux coupled to the secondary winding is controlled, thereby relative reluctance, the amount of magnetic AC flux econtrolling the output voltage provided by the secondary winding.

Abstract: A ferroresonant regulator for use in an inductively coupled high frequency power distribution system. A constant current resonant power source, comprising a sine wave oscillator (12), an amplitude controlled amplifier (16), a power amplifier (20), and an impedance matching transformer (24), provides current at a frequency of 38 kHz to a supply loop (68) that is installed in the floor of an aircraft passenger space. A current sensing transformer (32), and a voltage sensor (46) produce feedback signals that are used to control the amplitude of the current circulating in the supply loop, maintaining it substantially constant. A plurality of multiturn coils (70) are disposed proximate the supply loop. Connected to each of the multiturn coils is a saturable transformer (76), which includes a secondary winding attached to a load comprising an entertainment and passenger service system installed in each seat. A tertiary winding (106) on the saturable transformer is connected across a resonance capacitor (108).

Abstract: A power control device for a microwave cooking oven includes a regulator of the anode voltage of the magnetron and a heater voltage source. The anode voltage regulator includes a d.c. voltage bridge-type converter, a transformer, a rectifier and a filter. The heater voltage source includes a half-bridge d.c. to a.c. voltage converter. The half-bridge and bridge converters are controlled each by signals coming from the respective generators of pulse sequences.

Abstract: A DC-DC converter having a transformer having a primary winding and a secondary winding; means for supplying DC input voltage to the primary winding; at least one switching element connected between the DC input voltage supplying means and the primary winding; rectifying means; at least one saturable reactor having a first winding and a second winding, the first winding being connected between one end of the secondary winding which is positive while the switching element is in a turn-on state and the rectifying means; and reset control circuit means connected to the second winding of the saturable reactor for supplying reset voltage thereto in response to output voltage of the rectifying means. The first and second windings have such polarities that the reset voltage can reset the saturable reactor during a turn-off period of the switching element. This DC-DC converter enjoys less temperature rise in the saturable reactor and a lower level of noise generation.

Abstract: A power transfer circuit includes first and second windings (L1, L2) sharing a common magnetic core (101). Each winding has associated with it a parallel capacitor to thus form a pair of "tank" circuits. The first winding (L1) is connected at one end to a voltage supply and, at the other end, to ground through an FET switch (100,200). The switch (100,200) is turned on and off at a predetermined frequency and at a 50% duty cycle. The second winding (L2) and associated capacitor (C2) achieves parallel resonance at the predetermined frequency. Similarly the combined first and second windings (L1,L2) and associated capacitors (C1,C2) achieve parallel resonance at said predetermined frequency. The second winding (L2) need not be electrically connected to the first winding (L1) which transfers energy to it through the magnetic core (101). The transfer circuit efficiently couples power across a dielectric interface to a pickup coil (L3).

Abstract: A PWM inverter including a saturable core and a main circuit comprising a series circuit of a main winding and a resistor in which switching means applies a DC voltage across the main circuit by time ratio control with the polarity inverted alternately, and the on-off control of the switching means is accomplished by using a saturable transformer with a saturable core.

Abstract: A power supply is disclosed which comprises a ferroresonant circuit, the ferroresonant circuit including a transformer with a core of magnetic material, a primary winding, a secondary winding, and reactive means coupled with at least one of the windings. The transformer also has at least one bias winding. An alternating voltage is applied to the ferroresonant circuit, the alternating voltage having a frequency that is approximately equal to a resonant frequency of the ferroresonant circuit. An output circuit is coupled to the secondary winding. A signal from the output circuit is applied as a feedback signal to the bias winding to control DC flux bias of the core. In an illustrated embodiment, the means for applying an alternating voltage signal to the ferroresonant circuit includes an oscillator for generating alternating voltage control signals, and a switching circuit responsive to an input power source for generating the alternating voltage signals under control of the oscillator.

Abstract: A resonant forward converter at a switching frequency of 10 MHz provides a small volume point-of-load converter for distributed power systems. The leakage inductance of a transformer is made negligibly small relative to the magnetizing inductance of the transformer. This enables a resonant controllable switch on the primary side of a transformer and a secondary side rectified diode to be switched either on or off at the same time. The capacitance across the primary side switch and the secondary side diode rings with a resonant inductor connected in parallel with the transformer. Both the switch and diode, therefore, have zero voltage switching transitions. Further, the resonant inductor being connected in parallel with the transformer provides a resonant ring that is independent of load.

Abstract: A method and apparatus are disclosed for use with a battery powered inverter for powering a load through a ferroresonant transformer. The current flow through the inverter-ferroresorant transformer is sensed and is utilized to modulate the inverter's pulse width at a point, after a peak voltage but before saturation begins, when the slope of the inverter-ferroresonant transformer current with respect to time is at or near zero. A maximum current limiting feature can be provided in the method and apparatus of the present invention.

Abstract: A battery charger for incorporation into an electric-powered vehicle is disclosed. The charger includes a ferroresonant voltage-regulating circuit for providing an output voltage proportional to the frequency of an input AC voltage. A high frequency converter converts a DC voltage supplied, for example, from a rectifier connected to a standard AC outlet, to a controlled frequency AC voltage which is supplied to the input of the ferroresonant circuit. The ferroresonant circuit includes an output, a saturable core transformer connected across the output, and a first linear inductor and a capacitor connected in series across the saturable core transformer and tuned to resonate at the third harmonic of the AC voltage from the high frequency converter. The ferroresonant circuit further includes a second linear inductor connected between the input of the ferroresonant circuit and the saturable core transformer.

Abstract: An inductor structure is combined with a ferroresonant regulator as a filter inductor in one instance, and as a regulating inductor in another. In one example, a ferroresonant voltage regulator includes a pair of shunt filters at its output to reduce the low order odd harmonic content of the AC output. The filtering arrangement includes two LC shunt filters having their independent inductor windings wound on a single magnetic core unit. Auxiliary windings coupled to each of the inductor windings are placed in series with the output to buck any remaining harmonics.In a second instance, independent regulating inductors in a multiphase ferroresonant regulator are also realized on a single magnetic structure.

Abstract: The primary winding of a high leakage inductance power tranformer is coupled to a source of unregulated voltage and to a square wave voltage generator that includes first and second alternately conducting output switching transistors. A voltage controlled oscillator establishes the operating frequency of the voltage generator. A resonating capacitor is coupled to a transformer secondary winding that is loosely coupled with the primary winding. The capacitor forms a series tuned circuit with the leakage inductance between the primary and secondary windings of the transformer. The operating point of the tuned circuit voltage verses frequency characteristic curve determines the amplitude of the generally sinusoidal output voltage across the secondary winding, in accordance with the operating frequency of the square wave voltage generator. A feedback circuit senses the amplitude of the output voltage and varies the frequency of the voltage controlled oscillator to regulate the output voltage.

Abstract: A magnetically controlled switching regulator which controls an output voltage using a saturable reactor, wherein the saturable reactor is constituted by a first winding through which an output current flows and a second winding through which a reset current flows. The energy for resetting the saturable reactor is supplied from a capacitor in a smoothing circuit for an output voltage. A turn ratio between the first and second windings is set so that a sufficiently high reset voltage is obtained. Since the reset current of the saturable reactor does not flow through a transformer, the saturation of the transformer and a high increase in temperature thereof do not occur, so that the core of the transformer can be miniaturized and a high gain of the output voltage control circuit can be derived.

Abstract: A self-oscillating power converter utilizes a MOSFET power transistor switch with its output electrode coupled to a tuned network that operatively limits the voltage waveform across the power switch to periodic unipolar pulses. The transistor switch may be operated at a high radio frequency so that its drain to gate interelectrode capacitance is sufficient to comprise the sole oscillatory sustaining feedback path of the converter. A reactive network which is inductive at the operating frequency couples the gate to source electrodes of the transistor switch and includes a variable capacitance as a means of adjusting the overall reactance, and hence the converter's switching frequency in order to provide voltage regulation. A resonant rectifier includes a tuned circuit to shape the voltage waveform across the rectifying diodes as a time inverse of the power switch waveform.

Abstract: A deflection circuit is coupled to a horizontal deflection winding for generating scanning current in the winding. A retrace pulse voltage is developed across the deflection winding during the retrace interval. A flyback transformer is coupled to the deflection circuit and has retraced pulse voltages developed across windings thereof. A source of supply energy is coupled to a first winding of the flyback transformer and a load circuit, such as a high power audio circuit, is coupled to a second winding of the transformer and draws load current therefrom. A switched mode power supply is coupled to the source of supply energy and to the flyback transformer for controlling the transfer of energy between the source and the load circuit. A compensation circuit responsive to the operation of the switched mode power supply produces variations in current in an inductance coupled to the flyback transformer. These variations are indicative of variations in load current drawn by the load circuit.

Abstract: A switching power supply has a saturable transformer provided with first to fourth windings. The first winding is inserted in series in a first path from a DC power source to a primary winding of a power transmitting transformer. A main switch is inserted in series in the first path and controlled by an output of the second winding. The operation of the main switch is positively fed back through the saturable transformer. A capacitor is connected in parallel to a series circuit consisting of the main switch and the first winding. An auxiliary source for generating a predetermined direct current output is provided to drive the third winding by a polarity opposite to that of the first winding. An auxiliary switch is inserted in series in a second path from the auxiliary source to the third winding and controlled by an output of the fourth winding. The operation of the auxiliary switch is positively fed back through the saturable transformer.