Abstract: For use with a power converter having first and second power switches coupled between a converter input and a primary winding of a transformer to impress an input voltage across the primary winding, a voltage clamp circuit for, and method of, resetting the transformer and a power converter employing the clamp circuit or the method. In one embodiment, the clamp circuit includes: (1) first and second reset windings coupled between the first and second power switches, (2) first and second energy storage devices coupled between the primary winding and the first and second reset windings, respectively, and (3) first and second switching circuits, coupled to the first reset winding and the second reset winding, respectively, that provide an electrical path from the primary winding to the converter input through the first and second reset windings, respectively, when the first and second power switches are not conducting.

Abstract: An improved circuit and device uses a dual primary winding transformer, where the primary windings are connected in series, and where each winding has a center tapped ground. A series of four switches are attached to the ends of the two primary windings to sequentially feed the primary windings. The switches are controlled by a pair of oscillators, the first two switches on one primary winding controlled by a first oscillator, and the second two switches of the other primary winding controlled by a second oscillator. Both the first and second oscillator are controlled by a phase displacement controller which can vary the relative timing of the two oscillators to control the transformer output. A zero phase angle delivers maximum power, while a 180.degree. phase displacement delivers zero power, enabling precise control across the zero to full power spectrum. A series of feedback controls measure the current and voltage of the output of a rectifier bridge to even more closely control the power output.

Abstract: An improved circuit and device uses a dual primary winding transformer, where the primary windings are connected in series, and where each winding has a center tapped ground. A series of four switches are attached to the ends of the two primary windings to sequentially feed the primary windings. The switches are controlled by a pair of oscillators, the first two switches on one primary winding controlled by a first oscillator, and the second two switches of the other primary winding controlled by a second oscillator. Both the first and second oscillator are controlled by a phase displacement controller which can vary the relative timing of the two oscillators to control the transformer output. A zero phase angle delivers maximum power, while a 180.degree. phase displacement delivers zero power, enabling precise control across the zero to full power spectrum. A series of feedback controls measure the current and voltage of the output of a rectifier bridge to even more closely control the power output.

Abstract: A power factor correction controller is disclosed which extracts RMS information from a rectified AC input line voltage signal using a sample and hold analog to digital conversion approach. The controller then processes a digital word representing the RMS information through the application of a programmable mathematical function. The result is converted to analog form and provided as an input to an analog multiplier. The controller also monitors the output load power of an isolated boost converter circuit and linearly reduces the overlap delay time of a MOSFET transition switch when the load power decreases.

Abstract: A circuit for supplying power to a fluorescent lamp comprising a buck regulator with a high side drive. A dc battery is coupled to a drain of a first transistor. A source of the first transistor is coupled to an inverter for powering the lamp. A first control signal is coupled to a primary winding of a transformer. A first terminal of a secondary winding of the transformer is coupled to the anode of a diode. The cathode of the diode is coupled to the gate of the first transistor. A second terminal of the secondary winding of the transformer is coupled to the source of first transistor. The first control signal is activated to bias the first transistor through the transformer by charging the gate to a voltage higher than the control voltage due to the transformer turns ratio. A diode is coupled to capture a charge on the gate. A second transistor is coupled to the gate of the first transistor to drain the captured charge to ground, turning off the first transistor when a second control signal is activated.

Abstract: A voltage-suppressed voltage source which uses switching devices to maintain a high performance, stable DC voltage by suppressing unstable DC voltages and providing a stable supply of power to a load. The voltage source has a partial resonance circuit for reducing power consumed while a switching device in the voltage source turns `on` and `off`.When a first switching device is off, unsuppressed DC voltages are stored in a resonance capacitor. When the first switching device is turned on, a resonance current flows from the resonance capacitor through a resonance coil and a second switching device just before the first switching device is turned on. This resonance current also induces a suppression effect to the output voltage, and allows the voltage suppressing portion to pass a current in the same direction as when the first switching device is on.

Abstract: Here is disclosed a push-pull inverter characterized by a thin and small-sized boosting transformer improved to require a dielectric strength as low as possible and to be free from leakage current as well as noise. To realize such improvement, the boosting transformer is provided with a first secondary coil and a second secondary coil between which an impedance element such as a capacitor is connected so as to form together a serial circuit section, an output side of the first secondary coil is connected in a manner to have a same potential as a negative potential of a DC source and a load such as a fluorescent lamp is connected to the respective output sides of the first and second secondary coils.

Abstract: A DC power supply apparatus includes a rectifier circuit for rectifying an input AC voltage to develop a rectified voltage between two output terminals thereof. First and second smoothing capacitors are connected in series between the output terminals of the rectifier circuit. First and second voltages developed across the first and second capacitors are applied to first and second inverters which convert the applied voltages to high-frequency voltages, which, in turn, are applied to a transformer. The transformer develops a transformed high-frequency voltage which is converted to a DC voltage by a converter. A voltage detector detects the first and second voltages, and the detected first and second voltages are compared in a microprocessor. An inverter control circuit controls the first and second inverters in accordance with the result of comparison, in a sense to make the voltages across the first and second smoothing capacitors equal.

Abstract: A circuit technique that substantially reduces the boost-converter losses caused by the reverse-recovery characteristics of the rectifier is described. The losses are reduced by inserting an inductor in the series path of the boost switch and the rectifier to control the di/dt rate of the rectifier during its turn-off. The energy from the inductor after the boost switch turn-off is returned to the input or delivered to the output via an active snubber. The same technique can be extended to any member of the PWM-converter family.

Abstract: A DC-DC converter includes a transformer with two oppositely-wound primary windings, one on each side of a center tap, and at least one secondary winding connected to a load having a given capacitance. A reference voltage source is connected to the center tap of the transformer via an inductor so that the transformer is driven by a current source. Two switching devices are each connected in the return path of the reference voltage and in series with a respective primary winding. A control unit alternately and periodically connects the return path for the reference voltage to one or other of the primary windings. The control unit includes an oscillator generating squarewave signals has two complementary outputs connected directly to a control terminal of a respective switching device. The frequency of the oscillator is substantially equal to the resonant frequency of a circuit comprising the secondary inductance of the transformer and the capacitance of the load.

Abstract: A power converter for converting an input signal having an input DC voltage level to an output signal having a desired output DC voltage level. The power converter includes a switching converter having an input which receives the input signal and a floating differential output which includes a first output and a second output. The switching converter is operative to convert the input signal to an offset voltage equal to a difference between the desired output DC voltage level and the input DC voltage level. The offset voltage is generated across the first output and the second output of the floating differential output. The input signal is applied to the second output of the floating differential output to sum the input DC voltage level with the offset voltage and thereby produce the desired output voltage level at the first output.

Abstract: A single-stage power converter has an input-to-output transfer characteristic with two portions, each having a different operational characteristic, with each portion being selected by changing ONLY the duty-cycle of the power switching devices. At low input voltage the converter operates as a Boost converter, while operating as a Buck converter for greater input voltages. This transfer characteristic is provided by a circuit wherein the primary winding center tap of a split-primary power transformer is coupled through an inductive element, with one of the pair of push-pull power switching devices connected to each primary winding end. Secondary winding rectification and filtering provides the power supply output in the Boost mode, and a portion of the power supply output in the Buck mode.

Abstract: A power converter circuit provides low conversion losses, low generated noise and output power controllability. The circuit includes a controller, at least two transistors and an output network that provides impedance matching and operating point stabilization functions. The output network also enables zero voltage switching of the transistors, thus reducing radiated noise and minimizing (and possibly eliminating almost completely) switching losses. The controller circuitry includes an oscillator which is capable of self synchronizing to the resonant frequency of the components of the output network. Power modulation (e.g., for dimming of a lamp) is accomplished simply by desynchronizing and increasing the oscillator frequency. Thus, the control architecture allows the use of external parts of lower precision and cost while providing dimming capability in a single stage.

Abstract: A power source apparatus comprises a DC power source, a switching element, and a controller for performing an ON/OFF operation of said switching element at a predetermined switching frequency. The power source apparatus chops an output from the DC power source to control a DC output to be supplied to a load, or temporarily converts the output from the DC power source into an AC voltage to transform the DC voltage and supplies the transformed voltage to said load. The controller includes an external clock input terminal and a sync circuit for causing the switching frequency to coincide with a frequency of a clock applied to said external clock input terminal or a frequency which is an integer multiple of the frequency of the clock.

Abstract: A switching regulator composed of a push-pull converter with a buck or boost regulator connected upstream. The output inductance of the regulator is split into two separate inductances each of which is fed to one leg of the push-pull circuit. The push-pull converter is expanded to a resonance converter by means of resonance capacitors. This switching regulator has a high efficiency and is particularly suitable for use in satellite power supplies.

Abstract: An AC high-voltage power supply circuit, adapted for use in an image forming apparatus, for example in the separation charger of an electrophotographic copier, and capable of controlling the DC component of an AC high voltage, over a wide range including positive and negative regions. The power supply circuit includes, at the low voltage side of a secondary coil of an AC high-voltage transformer, a DC constant current circuit consisting of a transistor and a diode, a constant voltage circuit opposite in polarity to the DC constant circuit, and a detection circuit for detecting the DC component of a load current. The outputs of the constant voltage circuit and of the DC constant current circuit are controlled according to the output of the detection circuit. Such a device has a simple structure, provides a wider control range of the DC component including positive and negative regions, and has a lower power loss than previous power supply circuits.

Abstract: A low loss clamp circuit is provided for a dc to dc converter. The converter has a transformer with a secondary winding and a secondary circuit and a center tap primary winding. A dc voltage input is supplied to the primary winding center tap and to a circuit ground. A rectifier such as a bridge rectifier connects to two ends of the secondary winding and to the circuit ground to supply a dc output voltage. A pair of semiconductor switches such as FET switches are provided. Each end of the primary winding is connected through a respective switch to the common ground. The various circuits have energy storage means including the input capacitor 31 and input choke 32 in circuit with the primary winding. It will also be noted that the output capacitor 29 is a part of the energy storage means. This energy storage means is connected to return energy to the secondary circuit, not the primary circuit.

Abstract: A pulse width modulation DC to DC converter operates in an open loop mode to convert the DC output of the AC to DC converter to a desired, predetermined DC level using pulse width modulation techniques and a switching configuration substantially similar to that of the AC to DC converter.

Abstract: A command modulation system receives commands from a plurality of input sources, some local and some remote, and routes the commands to a plurality of commanded devices, which may be satellites. By use of the input sources, a user configures digital signal processors located in each of a plurality of modulation channels so that the channels have the desired modulation parameters. In this way, the system can be made to command a plurality of different types of commanded devices.

Abstract: An electrical power inverter having an output voltage waveform that closely corresponds to a reference waveform under a wide range of load conditions is disclosed. The present invention allows for excess energy present at the output port of the electrical power inverter to be coupled back to the input port to maintain the correspondence of the output voltage waveform with the reference waveform when the inverter is providing power to inductive or light resistive loads.

Abstract: An image forming apparatus includes: a photosensitive drum; a charging unit which is brought into contact with the drum and charges it; a developing unit for obtaining a visible image from an electrostatic latent image formed on the drum; a charge high voltage generation circuit for supplying an output which is obtained by multiplexing a high AC voltage with a high DC voltage with the charging unit; a development high voltage generation circuit for supplying an output which is obtained by multiplexing a high AC voltage with a high DC voltage to the developing unit; and a sync circuit for synchronizing a high voltage alternating current of the charge high voltage generation circuit and a high voltage alternating current of the development high voltage generation circuit. A ratio of the frequencies of the high voltage alternating currents of the development high voltage generation circuit and the charge high voltage generation circuit is set to an integer.

Abstract: Galvanic isolation device for direct current electrical signals or electrical signals likely to include a direct current component, which includes a transformer (T), reversible switch I for chopping the incident signal applied to one wind of this transformer reversible switch I' for chopping the signal obtained at the other winding of this transformer, controlled either in phase or in phase opposition with each other and filters (F1,F2) for filtering the chopped signals respectively obtained at windings of the transformer.

Abstract: A high voltage power supply having a low voltage input comprising a transformer having a primary winding, an input switching means coupled to the primary, first and second groups of secondary windings each of which are sub-divided into a plurality of component windings, and voltage converters coupled to each of the component windings for producing series output voltages of opposite polarities across the groups of secondary windings. First and second output switching means alternately switch the series output voltages to provide an intermediate voltage at a common point which is the input of a diode capacitor multiplier circuit thereby producing at its output a high voltage output.

Abstract: A current supply has a first voltage summing circuit with two inputs, one of which receives a signal that indicates a desired current level to be produced. A current source produces a current level at an output in response to a control signal received from the first voltage summing circuit. The current source output is coupled to a center tap of the primary winding of a transformer that has a capacitor connected across the end terminals of its primary winding. Separate transistors connect ends of the primary winding to a common node and a resistor couples the node to circuit ground. A sensor produces a voltage e.sub.i that is proportional to a magnitude of the current flowing through said capacitor. A second voltage summing circuit produces an output voltage e.sub.t equivalent to the sum of voltage e.sub.i and the voltage across the resistor and the output voltage e.sub.t is applied to the other input of said first voltage summing circuit.

Abstract: A digital controlled converter (100) for converting an input signal to a direct current signal having a clock generator (104) for generating a high frequency clock timing signal and a driver circuit (106) for controlling the passage of the high frequency clock timing signal within the converter (100). A power output stage (102) which provides an output signal is controlled by the driver circuit (106). A control loop (108) is provided for sensing and converting the output signal to a command signal. A latch (128) is utilized for latching the command signal and for controlling the state of the driver circuit (106). The latch (128) is reset at the rate of the high frequency clock timing signal and updated with the command signal to provide incremental correction to the output signal. The converter (100) comprises a transient response to variations in load proportional to the high frequency clock timing signal.

Abstract: A DC to AC power converter is disclosed which is connectable to a DC source, and including a first and second pair of switches which converts the DC source directly to AC by alternately switching between each of the first pair of switches at high frequency modulation, and between second pairs of switches alternately switching at each of the half cycles of the low frequency fundamental output voltage, for producing a positive pulse train and a negative pulse train. A transformer boosts the source voltage to the desired high voltage of the output of the converter circuit. A filter is connectable to an AC load and having a plurality of damping modes for extracting fundamental frequency from the output of the transformer, and having a control responsive to a signal for switching between damping modes. A sine wave oscillator generates a sine wave at the fundamental frequency. Feedback circuits maintain the AC output at the fundamental frequency.

Abstract: An unregulated D.C. input voltage (V.sub.IN) is processed by a high power chopper (34,36) to produce a first chopped signal having the same voltage as the input (V.sub.IN), and by a low power chopper (56,58) to produce a second chopped signal in synchronism with and having a lower voltage than the first chopped signal. The first and second chopped signals are algebraically combined by transformers (52,54) to produce an A.C. output signal which may be converted to D.C. (V.sub.OUT). The second chopped signal may be controlled to have the same polarity relative to the first chopped signal in which case the voltages add to increase the output voltage (V.sub.OUT), or to have the opposite polarity relative to the first chopped signal in which case the voltages subtract to decrease the output voltage (V.sub.OUT). The periods of addition and subtraction are alternated within the period of the first chopped signal.

Abstract: The invention relates to a magnetic control process for transfering energy in a static converter comprising a voltage source (E) and an almost sinusoidal current generator IQS serially coupled with the primary winding of at least one saturable current transformer (TP). The secondary winding of the current transformer (TP) feeds a control circuit (C) which regulates as a function of one parameter, voltage or current, of this secondary winding the demagnetization of the whole magnetic circuit (TP) according to the desired energy transfer. The invention also relates to a static converter for implementing the method.

Abstract: A driving circuit for an inverter microwave oven which includes a push-pull voltage type inverter circuit having two sets of switching element groups each provided with more than two switching elements connected in parallel to each other for switching the D.C. current supplied from a D.C. power source, a control device arranged to set a period for simultaneously turning OFF the two sets of switching element groups and to alternately turn ON the switching element groups by the same duty cycle, a step up transformer supplied, at its primary winding having a center tap, with A.C. current from the inverter circuit, and a voltage doubler rectifier circuit connected to a secondary winding of the step-up transformer for supplying electric power to a magnetron through a capacitor.

Abstract: A zero current/zero voltage resonant DC to DC converter operating at high frequency, utilizes the series/parallel approach to power conversion. A resonant transformer assembly is inserted into either the primary or secondary of the main transformer, to optimize the operating parameters of the converter.

Abstract: Minimal energy storage is required in complementary converters, a family of zero-voltage switching circuits which achieve non-pulsating input and output currents by employing a ripple-cancelling technique instead of conventional filtering. The input voltage in these circuits is divided between a primary winding of a main transformer and a primary winding of a second transformer referred to as a complement transformer. The turns ratios of the two transformers are adjusted so that the secondary voltage of the complement transformer cancels the ripple in the rectified output of the main transformer. The symmetry of these circuits allows an AC voltage waveshape to be impressed upon the main transformer, independent of the load current passing through it. If desired, a sinusoidal voltage can be produced across the main transformer with only a small resonant current, which can be achieved with minimal energy storage.

Abstract: Method and circuit arrangement for generating a sinusoidal line AC voltage from a DC voltage. For generating a sinusoidal line AC voltage from a DC voltage, the DC voltage is converted into a square-wave voltage having voltage pulses whose durations are controlled in accordance with the variation of the sinusoidal line AC voltage to be generated. The square-wave voltage is transmitted via a high-frequency transformer. Subsequently, the transmitted voltage pulses are respectively tapped and filtered for a given chronological duration. A secondary side of the high-frequency transformer is respectively shorted during pulse pauses caused by the sinusoidal control of voltage pulse durations for a simultaneous constant applied pulse frequency. In these phases, energy is transmitted back to the source of the DC voltage via the high-frequency transformer. As a result, the circuit arrangement can also be employed as a charging circuit.

Abstract: A circuit for regulating a parameter by means of a bidirectional current chopper structure suitable for transferring energy from an input network to an output network via the bidirectional current chopper structure, the current flowing through the structure being in the form of a triangular wave. The circuit is particularly suitable for space applications.

Abstract: Magnetic direct current to direct current converter with the input isolated from the output. A pulse generator from the feedback is incorporated in the feedback circuitry to regulate the output relative to the input.

Abstract: A high efficiency power conversion at high frequencies with zero voltage switching is obtained by using magnetizing current of a transformer or parallel inductance to charge the switch adjunct capacitance and other capacitance during the dead time. A transformer is prevented from being loaded during the dead time. Loading of the transformer during the dead time is prevented by directing the output inertial current to a capacitor instead of through the rectifiers to the secondary of the transformer. This can also be achieved by using synchronized rectification that provides pulse width modulated regulation on the output and ensures that the transformer secondary is separated from the inertial current of the output during the dead time. Voltage and current stresses on the switching devices and rectifiers are minimized. Zero voltage switching may be applied to inverters where the load is resistive.

Abstract: A self-oscillating inverted rectifier has a series-resonant circuit connected between a load and the selector terminal of an electronically controllable switch, the other terminals of which are connected respectively to d.c. sources of different potential. Phase detection and feedback circuits provide a rectangular control wave for connecting and disconnecting the resonant circuit to each d.c. source only at null transits of the current in the resonant circuit. The feedback circuit includes a control circuit supplied with a regulation voltage, which may be derived from the load, whereby the switch is intermittently prevented from connecting the resonant circuit to energizing d.c. for an integral number of half cycles of the resonant frequency. The load may be a high-frequency electrosurgical device or, more generally, a rectifier circuit providing accurately regulated d.c. power to a variable load.

Abstract: A circuit for regulating an electrical parameter to be servo-controlled by transferring electricity between two networks (11, 12), wherein the circuit (10) is a bidirectional current circuit providing electrical isolation between the two networks (11, 12). The circuit is particularly applicable to space applications.

Abstract: A fixed frequency resonant mode DC to DC converter maintains a constant DC output voltage using a saturable inductor or saturable transformer in series with an inductor and capacitor. The output voltage of the converter is derived from the voltage drop across the saturable inductor or saturable transformer. The series inductor and capacitor force current through a switch to have a value of zero. The switch is then operated when the current through it is zero.

Abstract: In a driving circuit for a stepping motor in which a phase current corresponding to a predetermined reference voltage is generated when an excitation signal for each phase of the stepping motor is being produced and a coil of the corresponding phase is excited by the phase current, the supply time of the phase current is controlled by the pulse signal of a pulse generator for varying the pulse width, thereby improving the rising state of the phase current.

Abstract: Regulation of an AC or DC voltage is achieved by processing a major portion of the prime power through a square wave inverter and a small portion of the prime power through a pulse width modulated switching regulator. The methods of regulation generally comprises the steps of: processing the unregulated input voltage to provide an output voltage; regulating an unregulated portion of the input voltage in response to a feedback signal indicative of the output voltage to provide a regulating voltage; and combining the regulating voltage with the output voltage to generate a regulated output voltage. The regulator circuit includes a square wave inverter circuit that produces a voltage in an output transformer, while a pulse width modulator regulates the output voltage in response to a feedback signal.

Abstract: A load is controlled by a pulse waveform from a source. The source and load are electrically isolated by using two monostable circuits to detect the leading and trailing edge of the pulse waveform, two pulse transformers to isolate the source and the load, and a bistable circuit to reconstruct the original pulse waveform.

Abstract: A start controlling circuit for delivering a start signal to a constant current generator to cause the latter to supply an output current to a load through which a load current flows. The load current is detected to produce a detection voltage indicative of the load current. A variable control voltage is converted into a first pulse sequence having a repetition period decreasing in response to a rise in the control voltage, and the first pulse sequence is processed into a second pulse sequence having a pulse width which increases in response to such a rise. The second pulse sequence is supplied to the constant current generator as the start signal. An error signal is produced representing the difference between the detection voltage and a gradually rising d.c. reference voltage. The error signal is amplified and applied as the control voltage. The reference voltage is varied when variations in the load result in a change in the load current.

Abstract: A regulator includes a switching transformer (TR) whose primary winding is divided into two halves through which current flows alternatingly via one respective switching transistor (Q1, Q2). The pulses on the secondary side of the transformer are rectified to attain the output voltage. The output voltage is controlled by pulse width modulated driver pulses for the two switching transistors. A protective circuit (12) with immediate effect terminates the currently applied driver pulse when the current flowing through the conductive switching transistor reaches a critical current value. A protective circuit (14) with delay effect prevents the generation of further driver pulses upon a further increased overload, this prevention being limited with respect to time. The protective system directly is controlled by the primary current of the power regulator.

Abstract: An improved DC to DC conveter is disclosed which is highly stable and has a highly regulated ouptut voltage. A pulse width modulator drives a switch for interrupting the flow of current through an inductor. A combination of feed forward and feedback control of the pulse width modulator is provided with the majority of control being provided by the feed forward component. The pulse width of the pulses from the width modulator is directly proportional to the feed forward and feedback components of the pulse duration control signal. Preferably, approximately 75%-90% of the pulse duration control signal is provided by the feed forward component.

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: In a dc-to-dc converter, alternating current or pulsating direct current produced by a cyclically switched power supply passes through semiconductor rectifiers or diodes. The rectifiers may be subject to unwanted conduction characteristics attributable to charge storage, which may result in cyclical current spikes during normal operation. A current sensor is coupled to sense a current which includes the cyclical spikes. A controllable attenuator or gain element couples the sensed current in a feedback loop to shut down the converter in the event of an overcurrent. To reduce the possibility of shut-down due to the normal cyclical current spikes, the attenuator or gain element is cyclically switched so as to reduce the sensitivity to the current spikes when they occur.

Abstract: A high-frequency resonant power converter transforms a relatively low D.C. input voltage to a relatively high A.C. link voltage to drive a resonant circuit. The high A.C. voltage appearing across a resonance circuit high-voltage capacitor is then transformed down to a relatively low value and rectified to obtain a desired relatively low D.C. output voltage. Use of a high A.C. link voltage eliminates low voltage operation of the resonance circuit, which would require very large resonant capacitors having high current ratings. Composite magnetic structures which combine a resonant inductor and a transformer are also disclosed.

Abstract: Disclosed is a resonant DC-DC converter which comprises an inverter for converting DC power into AC power, a rectifier connected to the AC output of the inverter through a resonant transformer for rectifying AC output power of the transformer to obtain DC power to be applied to a load, means for determining respective operation phases of a first, a second, a third and a fourth switching elements constituting the inverter in accordance with set signals indicating a voltage and a current to be supplied to the load, and a phase control circuit for controlling the respective operation phases of the first, second, third and fourth switching elements on the basis of an output signal of the phase determining means in a manner so that the first and second switching elements are alternately turned on with a phase difference of 180 degrees with respect to an operation frequency of the inverter, the third and fourth switching elements are alternately turned on with a phase difference of 180 degrees with respect to the o

Abstract: A power supply system including a DC-to-AC inverter stage and a voltage step-up transformer is intended to have the output voltage settlement with a minimal delay and suppressed bounce at the start-up of power supply to the load, and also intended to reduce the load voltage bounce caused by the leakage inductance and stray capacitance of a high tension step-up transformer.

Abstract: Magnetic direct current to direct current converter with the input isolated from the output. A pulse generator from the feedback is incorporated in the feedback circuitry to regulate the output relative to the input.