Abstract: The input side of a DC:DC converter emulates current fed topologies and replaces an active switch and associated components with a passive inductor, coupled between Vin and upper nodes of the primary transformer windings, that smoothes input current. Several output side topologies are disclosed that may be used with any input side configuration, and require no output snubbers. The output topologies use non-center-tapped secondary windings that are utilized 100% of the time. The output topologies advantageously use series-coupled capacitors, which configuration distributes voltage stress. The topologies advantageously provide two output voltages, Vo1 and Vo2≈Vo1, or Vo2≈−Vo1. The snubber-less output side topologies provide very low EMI content waveforms that may be switched at relatively high frequencies.

Abstract: An ON-LINE uninterrupted power supply (UPS) of this invention serving as a long term high quality power supply for web, telecommunication, security system, etc is characterized in detecting a ring signal from far end for ON/OFF control of an output power and in permitting omni-range input civil power to avoid any unstable output power.

Abstract: Zero voltage switching isolated boost converters that provide high efficiency power conversion between input and output DC voltages. The boost converters includes a voltage amplifying stage including first and second switching transistors, an input coupled inductor, and an output transformer. The voltage amplifying stage amplifies the DC input voltage which is transformed by the output transformer to produce the DC output voltage. A zero voltage control input circuit is coupled to gates of the switching transistors and to the output of the voltage amplifying stage. The input circuit generates synchronization signals that synchronize rising edges of gate drive signals applied to the switching transistors with a resonant circuit. This is achieved by observing the state of gate and drain voltages of the switching transistors and detecting the moment when both drains are low, and both gates are not high.

Abstract: A four quadrant power conversion topology comprising a multi-winding inductor, four switches, and four diodes is disclosed. The four quadrant power conversion is utilized in a number of power conversion devices such as a power efficient non-linear power amplifier that comprises the 4Q power conversion topology of the present invention and a switch-control-signal generator coupled to the 4Q power conversion topology. The switch-control-signal generator generates switch activation signals for driving the four switches of the 4Q power conversion topology.

Abstract: A high magnitude potential supply comprises a first circuit (220, 224) for generating a first signal related to an output high magnitude potential (KV) across a pair of output terminals (113 and ground) of the supply, a second circuit (210, 218) for generating a second signal related to a desired output current from the high magnitude potential supply, and a third circuit (Q2B, Q2C, Q7 and associated components) for supplying an operating potential (VCT) to the high magnitude potential supply so that it can produce the high magnitude operating potential. The third circuit has a control terminal (COMP terminal of 86). The supply further comprises a fourth circuit (86) coupled to the first (220, 224) and second (210, 218) circuits and to the control terminal (COMP terminal of 86).

Abstract: An uninterruptible power supply with sine wave AC output and energy recycle function is disclosed. The uninterruptible power supply makes use of a DC/DC converter to boost and convert the DC voltage of a battery set to a full-wave rectified shaped DC voltage. A microcontroller is provided to generate a full-wave rectified shaped DC reference signal to force the DC/DC converter to follow the reference signal for adjusting its output to a full-wave rectified shaped DC voltage. The full-wave rectified shaped DC voltage is converted by an inverter to a sine wave AC voltage for providing uninterruptible power. An energy recycle charger is further provided to recycle redundant energy to the battery set.

Abstract: Various systems and methods for providing soft-start and soft-stop to an asymmetrical half-bridge converter and a power supply employing such systems or methods. The power supply includes a power train including an asymmetrical half-bridge converter having an energy storage device coupled across a complementary switch thereof. In one embodiment, a conductive path is coupled across the energy storage device to substantially discharge the energy storage device and thereby reduce current stress in the complementary switch when the converter turns on. In another embodiment, a controller, coupled to the complementary switch, provides a drive waveform to drive the complementary switch. The controller increases a duty cycle of the drive waveform as the converter turns off.

Abstract: The invention relates to an inverter including an output regulating mechanism which is simplified in its construction and suitable for reduction of the manufacturing cost. The output regulating mechanism comprises a volume control adapted to be applied with an input voltage for said booster transformer periodically changing as the inverter oscillates, control means adapted to pulse-convert the output signal of the volume control and thereby to output a control signal which has been pulse width modulated according to the output signal of the volume control, and switching means provided on an input current path for the booster transformer so as to be turned ON and OFF with the control signal provided from the control means.

Abstract: A direct current to direct current power converter device includes a transformer having a primary winding and at least one secondary winding. A first inverter is connected to the terminals of the primary winding of the transformer. At least one second inverter is connected to the terminals of the secondary winding of the transformer or of each secondary winding of the transformer. The first inverter or the at least one second inverter assures the inverter function when a voltage to be converted is applied to its terminals and the rectifier function when the voltage to be converted is applied to the at least one second inverter or to the first inverter.

Abstract: A personal computer includes a DC to DC converter which employs a dual function capacitive energy storage device at the output rail of the converter. The energy storage device provides both a transition control function and a bulk or output function. In this manner, the size and expense of a separate bulk capacitor is advantageously avoided. The converter includes a switching transistor coupled to a bulk inductor. The switching transistor exhibits a high frequency switching rate which is sufficiently high to permit the inductor to directly replenish the capacitive energy storage device thus enabling the converter to withstand both major and minor load fluctuations without loss of voltage regulation at the output rail.

Abstract: A method for reducing audible monotonic noise in a power conversion system (10) using one or more controllable converters (20, 120, 26, and 136) includes generating a set of pulse width modulated (PWM) signals so that each converter has a different average switching frequency, and randomly varying successive cycle time intervals of the generated signals so that a respective instantaneous frequency shift relative to the respective average switching frequency of the converters is achieved over each of the time intervals.

Abstract: A DC link power converter apparatus including a first DC to DC converter, a DC to AC converter and a load balancing storage element. The first DC to DC converter has first and second DC ports and the DC to AC converter has a third DC port and has an AC port. The first DC port is connectable to a DC source and the second DC port is connected to the third DC port. The AC port is connectable to an AC load. The load balancing energy storage element is connected to the second DC port for decoupling the DC to DC converter from the DC to AC converter by supplying energy to the third DC port when a voltage at the second DC port is tending to decrease and for storing energy received from the second DC port when a voltage at the third port is tending to increase.

Abstract: A switching regulator with its less ripples, less switching loss, and low noise, which is capable of being miniaturized with high efficiency is provided. PWM control signals outputted from a terminal T6 of a pulse width control circuit IC1 are inputted to delay circuits DLa and DLb, respectively. The PWM control signal inputted to the delay circuit DLa, only a rise of which is delayed by a resistor Ra and a capacitor Ca, is applied to a gate of FET Q2 via a wave shaping circuit IC2. On the other hand, the PWM control signal inputted to a delay circuit DLb, only a fall of which is delayed by the resistor Rb and the capacitor Cb, is inverted via a wave shaping circuit IC2 and is applied to a gate of FET Q1 as an inverted control signal. Therefore, FETs Q1 and Q2 are turned ON/OFF in a predetermined period, and a pause period where FETs Q1 and Q2 are turned OFF is only a delayed constant period.

Abstract: A current controlled voltage boost circuit for a high voltage converter. The voltage boost circuit includes a boost converter connected to receive an input voltage and a control signal, and output an increased output voltage to the high voltage converter as a function of a control signal. The circuit further includes a current sensing circuit providing an output voltage proportional to the sensed input current to the high voltage converter. The output voltage from the current sense circuit varies a reference voltage that is compared to the boost converter output voltage by an error amplifier. The error amplifier, in turn, outputs a control signal to the boost converter such that the control signal controls the boost converter output voltage as a function of the input current to the high voltage converter.

Abstract: A high magnitude potential supply comprises a first circuit for generating a first signal related to a desired output high magnitude potential across a pair of output terminals of the supply, a second circuit for generating a second signal related to an output current from the high magnitude potential supply, and a third circuit for supplying an operating potential to the high magnitude potential supply so that it can produce the high magnitude operating potential. The third circuit has a control terminal. A fourth circuit is coupled to the first and second circuits and to the control terminal. The fourth circuit receives the first and second signals from the first and second circuits and controls the operating potential supplied to the high magnitude potential supply by the third circuit. A fifth circuit is provided for disabling the supply of operating potential to the high magnitude potential supply in certain conditions so that no high magnitude operating potential can be supplied by it.

Abstract: A drive arrangement for a switched output stage, such as an output stage of a gradient intensifier of a tomography apparatus has a pulse-width modulator and drive logic for producing at least two drive signals. The drive logic produces, for each drive signal, an edge of each on-phase pulse at a time made fixed corresponding to a time reference clock signal thereby allowing a fine adjustment of the on-phase of the power transistors of the switched output stage with low components costs, and a prescribed dead time between the individual on-phases is reliably adhered to.

Abstract: Boost Mode Regulator techniques are used to provide regulated a.c. or d.c. output from a.c. or d.c. sources. One embodiment involves regulation of the output of an a.c. source to provide a regulated d.c. voltage. The source inductance becomes part of the boost mode circuit, thus avoiding the losses associated with the addition of external inductors. When a three-phase alternator is the power source, the circuit comprises a six diode, three-phase rectifier bridge, three FET transistors and a decoupling capacitor. The invention involves shorting the output of the power source to allow storage of energy within the source inductance. During this time, the decoupling capacitor supports the load. When the short is removed, the energy stored in the inductances is delivered to the load. Because the circuit uses the integral magnetics of the source to provide the step-up function, the efficiency of the design can be quite high.

Abstract: A high voltage pulse generating circuit for powering klystrons, and the like. The circuit includes a source of D.C. power having positive and negative terminals, a flyback transformer having a primary winding and a secondary winding, the primary winding having first and second terminals for connection to the source of D.C. power, a sensor for generating a signal indicating the amplitude of the current in the primary winding, and a solid state switching circuit for coupling the source of D.C. power to the primary winding of the flyback transformer. The primary winding is coupled to the power source in response to a control signal, and decoupled from the power source when a predetermined level of current is detected in the primary winding.

Abstract: A starting system for a prime mover coupled to a generator includes a step-up inverter which converts DC power at a first voltage into AC power at a second, higher voltage. Halfwave pulses in the AC power are selectively applied to the generator by a pulse-population inverter coupled to the step-up inverter such that the generator is operated as a motor to supply motive starting power to the prime mover.

Abstract: A boost converter for a power factor correction circuit having application in a DC power supply for telecommunication equipment. The boost converter has a pair of independently controlled switches such as MOSFET in series with an inductor. A capacitor is in parallel with each switch and the lossless resonant discharge of the capacitors by energy stored in the inductor eliminates switch losses at turn on. As a result the converter may be operated at higher frequencies, thereby reducing the size and cost of magnetic components in the power supply.

Abstract: A four quadrant flyback converter, employable as part of a ringing signal generator, includes: (1) a transformer having first and second primary windings of opposite polarity and a secondary winding, (2) first and second switches that alternatively couple the first and second windings, respectively, to a source of DC input power and (3) a bidirectional switch coupling the secondary winding to an output of the converter, the first, second and bidirectional switches switchable to provide a continuous waveform at the output.

Abstract: A PWM controlling circuit includes a signal generator and two PWM controllers. The signal generator comprises an oscillator, a plurality of inverters, and two RC delay networks. The oscillator and the inverters are composed of elementary elements, respectively, such as diodes, resistors, inverters and capacitors. The PWM controlling circuit in accordance with the present invention can be implemented with low cost, and the duty cycles thereof are not limited to 50%.

Abstract: A converter has an assembly with a transformer primary and secondary windings and two pairs of primary and secondary choke windings wound around a core. Switching circuits are coupled between the transformer primary winding and the two primary choke windings. Each switching circuit has a capacitor, diode and a MOSFET. The MOSFETs are switched on and off in a cyclical manner to provide a continuous output current from a continuous input current by operating in a push-pull manner.

Abstract: Disclosed is a method for operating a communications signal transmitter and apparatus for carrying out the method. The method includes the steps of receiving a communications signal; sensing an amount of user demand; adjusting an output of a power supply that supplies operating power to a communications signal transmitter amplifier in accordance with the sensed demand so as to increase the output of the power supply when the sensed demand increases and to decrease the output of the power supply when the sensed demand decreases; and amplifying the received communications signal with the communications signal transmitter amplifier.

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: The present invention provides a transformer which uses bi-directional syronous rectification to transform the voltage of an input signal from one voltage level to another. The invention provides a transformer which requires less core volume, and hence mass, than conventional transformers, and includes a rectifier for transforming a first time varying input signal, such as a sinusoid or saw tooth signal, into a full-wave rectified voltage signal. A synchronous switch control generates first and second control signals in response to sampling the first time varying voltage signal. A floating drive buffer generates third control signals in response to receiving the second control signals. An AC switching stage transforms the full-wave rectified voltage signal into a first and second series of voltage pulses in response to receiving the first control signals. Each of the first and second series of voltage pulses has a pulse period, T, and a pulse width, .omega..

Abstract: A DC to DC converter repeatedly divides a first digital signal (26) into 8 time frames, and repeatedly generates a second digital signal (V.sub.S) during one of the 8 time frames. A DC input signal (V.sub.IN) is converted to a pulse width modulated signal (PWM) representative of the DC input signal, which is amplified and applied across a primary winding (4A) of an isolation transformer (4) during the one time frame. A second pulse width modulated signal produced across a secondary winding (4B) of the isolation transformer is rectified to produce a DC output voltage, which is compared to a reference voltage to produce a error signal. The error signal is transmitted across the isolation transformer during the one time frame and is used to adjust the pulse width modulating, to thereby regulate the DC output voltage.

Abstract: In an actuating and dual scanning integrated circuit, modulators 24 of respective programmable power regulators 11 transmit to respective power converters, energy transfer commands corresponding to programming performed in the circuit. Modulation of the modulators' output signals depends on the programming and on feedback received from output sites 7 that it controls. The circuit communicates through a series link with a main control system 28 so that the control system varies the circuit's programming and receives data corresponding to circuit performance.

Abstract: A voltage converter whose output voltage is determined by the duty cycle of at least one switch and which includes ripple steering circuitry, and a current source whose output current is determined by the duty cycle of at least one switch and which includes ripple steering circuitry. In some embodiments, the voltage converter includes at least one yoked switch pair, circuitry for controlling the duty cycle of the yoked switch pair, and ripple steering circuitry. Preferably, the voltage converter includes a transformer, an input side, an output side, and ripple steering circuitry implemented on the input side. Examples of voltage converters in the first class are forward converters, flyback converters, and full bridge forward converters.

Abstract: A converter has an assembly with a transformer having primary and secondary windings and two pairs of primary and secondary choke windings wound around a core. Switching circuits are coupled between the transformer primary winding and the two primary choke windings. Each switching circuit comprises a capacitor, diode and a MOSFET. The MOSFETs are switched on and off in a cyclical manner to provide a continuous output current from a continuous input current by operating in a push-pull manner.

Abstract: A universal input dimming circuit for coupling an isolated external control signal into a variable output power supply, particularly those used for driving fluorescent lamps. Circuitry is incorporated which allows to discriminate between a DC control voltage or a relatively low-frequency pulsewidth-modulated signal using the same pair of input leads. By appropriate conditioning and waveshaping, the circuit produces a pulsewidth-modulated output which is then coupled across an isolation boundary and then demodulated to provide a command signal to the dimming ballast.

Abstract: In a method of driving vibrating compressors having such a construction that a-c voltage is fed to a vibrating compressor by converting d-c voltage into a-c voltage with two MOS-FETs, the two MOS-FETs as switching elements are driven to convert d-c voltage into a-c voltage by changing the ON time of each of the MOS-FETs corresponding to suction and compression strokes in one cycle of the vibrating compressor to improve the operating efficiency of the vibrating compressor. To this end, suction and compression time in one cycle of the vibrating compressor is changed by means of a timer IC.

Abstract: A push-pull or forward switching power supply is operable over a voltage range of 4.5 to 40 volts at high efficiency. At low voltages a primary winding or pair of windings are activated by a PWM control to regulate the output current. At high voltages, an additional primary winding in series with each of the other winding or windings is also activated by a PWM control.

Abstract: Described is a drive circuit of a switching element for controlling a switching element.

Abstract: An apparatus for carrying out a current control and method therefor are disclosed in which the current control is such that no 0 vector defect is present by switching from a three-arm modulation method to a two-arm modulation method in the vicinity to a voltage saturation in a PWM inverter using the three-arm modulation method. The structure of the current control apparatus is such that in the PWM inverter using the three-arm modulation method having a time point data preparing section which prepares a time point data for the three-arm modulation mode from voltage vector times T .lambda., T.mu.

Abstract: Paralleled DC power supplies each comprise a half-bridge, resonant inverter (19-23) feeding a converter (25-28) connected to a common load 8. Current mode control (50-54) is provided (36) through a PWM IC (30) to which the output voltage (31) is fed back. Inverter capacitor imbalance is corrected (52, 55-59). Load sharing (71) is accommodated with offset compensating bidirectional buffer amplifier circuits (65-70, 74-76).

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 modular power supply system (10) is provided for providing a multiplicity of output voltages from a plurality of respective converter modules (70a-70n). Each of the converter modules (70a-70n) has an input coupled to a DC high voltage bus (22) from which a respective output voltage is generated. The voltage supplied on DC bus (22) is generated by a power factor corrected boost converter circuit (20) which is coupled to an AC input source (12). Further, a battery backup module (40) is coupled to the high voltage DC bus (22) for supplying backup power whenever the bus voltage drops below a predetermined level.

Abstract: In a voltage converter for switching mode, for example a push-pull voltage converter (GW), during a starting operation the switching-on pulses for the switching elements (S1, S2) are dimensioned to be of different length, specifically in such a way that the mean value of the energy-consuming current does not exceed a prescribed limiting value.By contrast with conventional methods, there is no regulation of the switching-on pulses, but the different switching-on times in a plurality of subphases are prescribed in a fixed fashion as a function of the inductance (LS) of the DC/DC voltage converter (GW).The method according to the invention ensures that the mean value of the inrush current cannot become substantially higher than a prescribed nominal value. This is advantageous, in particular, for the power supply of travelling wave amplifiers. FIG.

Abstract: An inverter/converter power supply system that employs pulse-width modulation controlled by an absolute-value representation of a reference wave. A low-frequency wave, such as a 60 hertz sine wave, is precision-rectified which then is the reference input of a pulse-width modulation controller (PWM). The PWM then produces a high-frequency square-wave signal whose pulse width changes as the amplitude of the rectified reference wave changes. The high-frequency square-wave signal is further rectified at an inverter/converter transformer secondary, whose output is filtered through a low-pass filter that removes the high-frequency component while minimizing the stored charge in the filter capacitor(s) to an amount easily drained by a small constant-current load across it. Feedback from the constant-current load to the PWM further adjusts the pulse-width to compensate for load variations and circuit losses.

Abstract: Pulse width modulating power supply circuitry is disclosed which manually or automatically controls the rail voltage setting of the amplifier circuitry. The maximum power rating of the amplifier will then be available to drive speakers with a pre-set impedance attached to the amplifier. A manual selection circuit provides a selector switch which places one or more resistors in parallel with a feedback resistor of a pulse width modulating controller which controls the setting of the rail voltages. In an automated mode the impedance of one of a set of speakers is measured at the time the amplifier is turned on and a resistor having a resistance appropriate to obtain maximum amplifier power output is placed in parallel with the feedback resistor in the pulse width modulating power supply controller by transformation circuitry. Light emitting diodes are wired into the resistor selection circuitry to provide an indication of circuit operation.

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 DC constant voltage circuit comprises a rectifier and a boosting chopper circuit controlled by a general purpose PWM control IC. The general purpose PWM control IC receives a reference voltage Vref which regulates the output voltage by pulse width modulation and produces a voltage having the same waveform and phase as the input current to improve the power factor of the output voltage. An AC constant voltage circuit comprises a common line connecting an AC input terminal and an output terminal, positive and negative boosting chopper circuits for boosting and chopping a half-wave rectified respectively in both positive and negative sides into a DC voltage and a DC-AC inverter for inverting the DC voltage into the AC output voltage. The positive and negative boosting chopper circuits are used as a filter for improving the power factor and adjusting the waveform and phase of the output voltage to be the same as the sine full waveform of the input voltage.

Abstract: A drive device for a push-pull stage includes a microcontroller in the form of a pulse-width modulator which, starting with a selected switching frequency, varies the pulse-duty ratio (modulation) of the pulse-width modulated output signal and which, with chronological delay, controls the push-pull stage. The push-pull stage has at least one upper and one lower power switch, and the microcontroller has three pulse-width modulation outputs. The actual pulse-width modulated output signal is delivered at the first output, the modulated signal plus a dead time is delivered at the second output and is supplied to the lower power switch as a drive signal, and the dead time by itself is delivered at the third output. The drive signal for the upper power switch is formed by the difference between the modulated signal and the inverted dead time is automatically decreased in the limit region of the modulation, i.e.

Abstract: A control apparatus for compressor with induction motor includes a microcomputer which evaluates an optimum number of rotations at which an operation efficiency of a compressor becomes a maximum when a frequency of an alternating current electric power applied to an induction motor in accordance with a change of a load. An inverter circuit is controlled by the microcomputer, and therefore, a voltage outputted from the inverter circuit is adjusted such that the induction motor becomes the optimum number of rotations.

Abstract: An inverter controlling a brushless motor includes a microcomputer detecting a rotational position of a motor rotor on the basis of comparison signals obtained by comparison of terminal voltages of respective windings of the brushless motor with a reference voltage, determining a commutation timing. The current flowing through a DC power line is detected by a shunt resistor and the detected current is sampled and compared sequentially by the microcomputer. The microcomputer obtains a compensation time period in accordance with the result of comparison. The commutation timing of each of switching transistors of the inverter is compensated with respect to a reference commutation timing by the obtained compensation time period. Alternatively, the microcomputer detects energization time periods of diodes as the commutation time periods on the basis of the comparison signals and determine the commutation timing from the detected commutation time periods.

Abstract: The bead source for the thermionic detector of a gas chromatograph is heated by the secondary winding of a transformer having a center-tapped primary and operating in the push-pull configuration. The voltage drop across the bead is compared with a preselected reference voltage and an error signal is generated. The error signal is used to control the output of a pulse width modulation control which supplies the transformer primary winding.

Abstract: The invention relates to a pulse-controlled converter, and a motor electric controller including such a converter. A first switch is controlled by pulses applied to its gate, these pulses being produced by a digital control unit linked to the gate of the first switch via a transformer. The transformer is linked to the digital control unit via a primary circuit and to the gate of the first switch via a secondary circuit. A second switch is directly controlled by the digital control unit. The secondary circuit includes a Zener diode and a resistor which are connected in series between a first terminal of a secondary winding of the transformer and the gate. The digital control unit generates a specific pulse synchronization sequence to control the converter so that problems of short-circuiting on the different bridge arms are avoided.

Abstract: A switching regulator having a series resonance push-pull converter (GW) and two clocked boost regulators (AR1, AR2) connected in series with the converter, wherein: the converter comprises a transformer (Tr) having two primary windings (w1, w2) which are galvanically isolated from one another, and two push-pull switches (S1, S2) each connected in series with a respective one of the primary windings; each of the boost regulators comprises a series inductance (L1, L2) and an output capacitor (C1, C2); and the boost regulators are connected to the converter to form two push-pull branches, each of the push-pull branches being composed of the series inductance of one of the boost regulators connected in series with a respective one of the primary windings and a respective one of the push-pull switches, and the output capacitor of each of the boost regulators constituting a resonance capacitor of the converter.

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.