Abstract: A SEPIC type voltage converter (101) comprises a transformer (40) having a primary winding (41) and a storage capacitor (33) connected in series, and a controllable switch (51) coupled in parallel with said series combination. The transformer has a first secondary winding (421) and a first rectifying diode (431) connected in series, and a first capacitor (441) coupled in parallel with said series combination, one terminal of said first capacitor (441) being coupled to an output terminal (451). The voltage converter also comprises feedback means (50; 53, 52) coupled to said output terminal (451) and controlling said controllable switch (51). The transformer further has a second secondary winding (62) and a second rectifying diode (63) connected in series, wherein this series combination is also coupled to said output terminal (451) in order to limit the voltage across the storage capacitor.

Abstract: An AC ripple current reduction circuit for an AC converter having: an AC voltage source at the input; a first capacitor across which the circuit output voltage is provided; a first, main inductor in series with the first capacitor and the input; an auxiliary circuit including a second capacitor and a transformer coupled to the main inductor, the secondary of the transformer being in series with the second capacitor; and a means for enabling the flow of a time varying voltage across the first and second capacitors that has a frequency much less than the ripple frequency of the current in the main inductor.

Abstract: A controller for use with a current-controlled frequency-modulated power factor corrector having a power switch therein, and a method of regulating the same. In one embodiment, the controller includes a sensing circuit configured to detect a sense current that is representative of an input current to the power factor corrector. The controller also includes a frequency modulation circuit, coupled to the sensing circuit, configured to provide a signal that causes at least one of: (a) an increase of a switching frequency of the power switch when the input current increases, and (b) a decrease of the switching frequency of the power switch when the input current decreases.

Abstract: A power converter module provides a regulated direct current voltage to a load, and includes a rectifier, a metal thin film capacitor, and a voltage regulating circuit. The rectifier has input rectifier terminals coupled electrically to an external alternating current power source, and output rectifier terminals. The metal thin film capacitor interconnects one of the input rectifier terminals of the rectifier to the external alternating current power source. The voltage regulating circuit provides the regulated direct current voltage from the output rectifier terminals to the load.

Abstract: A boost quantity detecting section (103) detects a boost quantity of an inductor (L11). An operational amplifier (113) of a control section (106) compares the boost quantity detected by the boost quantity detecting section (103) with a reference voltage (ES12). When a supply voltage supplied from an AC power source (100) reduces and an output voltage is unchanged, the boost quantity detected by the boost quantity detecting section (103) increases. When a signal level of a boost quantity detection signal is higher than the reference voltage (ES12), a control section (106) reduces a target level of a switching current. The target level of the switching current decreases, so that the output voltage decreases and energy loss due to boosting reduces.

Abstract: A motor control apparatus includes a fundamental wave current control system that controls a fundamental wave component of a motor current in an orthogonal coordinate system and a higher harmonic current control system that controls a higher harmonic component contained in the motor current in an orthogonal coordinate system. In the motor control apparatus, it is judged whether an output voltage from the power conversion device is in a saturated state, and a current control gain for the higher harmonic current control system is reduced if it is judged that the output voltage is in the saturated state.

Abstract: The present invention relates generally to the reduction of odd harmonics of phase angle controlled loads. One embodiment relates to an apparatus for reducing odd harmonic currents introduced into an alternating current (AC) supply by a load having a zero crossing detector and a processor coupled to the zero crossing detector. The zero crossing detector is coupled to the AC current supply for measuring voltage zero crossings of the AC current supply. The processor receives a user control signal for controlling the load, such as, for example, a speed control, determines phase angles required at the voltage zero crossings of the AC current supply to implement the user control signal, and selectively modulating the phase angles when they are in a predetermined range of undesired phase angles in order to selectively reduce odd harmonics within the AC current supply.

Abstract: A power supply device for low-voltage electronic residual current circuit breakers, comprising:

Abstract: A high density, multiple output switching power supply having internal, but externally accessible, mechanical programmability means, or computer generated programmability, whereby a mass-produced, fully tested standard base model can be stocked and reprogrammed at the distributor locations into any one of a multitude of substantially different models that is then delivered directly to the end user.

Abstract: The invention relates to a circuit for converting AC voltage in DC voltage for one or two consumers (Rm, Ra), in which a first part of the current is led via a large induction coil (L50) and a first rectifier (Gm) and a second part of the current via a second rectifier (Ga) before the large induction coil in the input side. As a result of the division of the supplied current the induction coil (L50) can be dimensioned accordingly smaller for smoothing the output voltage and, despite this, the circuit can at the same time satisfy relevant standard specifications.

Abstract: A cathodic corrosion inhibiting apparatus is disclosed which is characterized by outputting a substantially square-wave rectified output from a AC input. The square-wave rectified output has a substantially constant DC component and a minimal AC component which allows the output to minimize large oscillations in electromotive potential about a DC mean associated with traditional rectified cathodic protection apparatus. The apparatus of this invention is also designed to be remotely monitored and controlled and can include self-monitoring and control circuitry to maintain a given degree of corrosion protection to a metallic apparatus.

Abstract: An A.C./D.C. converter including a filtering capacitor and further including a first branch essentially including a first rectifying circuit and a current limiting circuit; a second branch essentially including a second rectifying circuit, the series voltage drop of which is limited to that of the switches forming it; and a selection circuit for selecting one of the two rectifying circuits.

Abstract: A power supply unit which supplies voltage to electric components, includes: a DC power supply (40) which supplies DC voltage to the electric components; at least one capacitor (C1), provided between the DC power supply (40) and the electric components, which charges the DC voltage; an input switch (SW1a) which connects or disconnects the capacitor (C1) and the DC power supply (40); and an output switch (SW1b) which connects or disconnects the capacitor (C1) and the electric components (semiconductor device under test); and a switching control unit (60) which charges the capacitor (C1) and supplies the DC voltage charged in the capacitor (C1) to the electric components. Thereby, the DC voltage to be supplied to the electric components or semiconductor device under test can be temporarily switched to low-noise DC voltage supplied from the charged-up capacitor (C1) during the test.

Abstract: A power-factor correction circuit of an electronic ballast for fluorescent lamps which includes an input full-wave rectification circuit for full-wave rectifying an AC input voltage from an AC input power source, a DC-link capacitor for supplying a DC-link voltage in response to an output voltage from the rectification circuit and a resonant inverter connected in parallel to the DC-link capacitor. The power-factor correction circuit comprises a charge pumping circuit disposed between the AC input power source and the rectification circuit, a valley-fill DC voltage supply circuit disposed between the rectification circuit and the DC-link capacitor, and a high-frequency full-wave rectification circuit disposed between the DC voltage supply circuit and the DC-link capacitor and connected to a secondary winding of a power transformer in the resonant inverter.

Abstract: A modified PWM space vector technique is described which includes a DC ripple voltage measurement scheme supplying feed-back to a DSP controller which then computes and generates the instantaneous PWM drives required for ripple voltage cancellation in a lightly filtered line voltage node, and executes the interface to the multi-phase power inverter circuitry. This preferably becomes a part of a closed loop motor speed control process. Use of the modified PWM drive in this manner greatly reduces the value of the filter capacitor required, allowing for the use of non-electrolytic capacitors having greater reliability and being available at lower cost.

Abstract: This invention provides a power supply device capable of widening a conduction period of an input current by a simple control to improve a power factor, and reducing a harmonic distortion of the input current. The power supply device comprises a rectifier circuit, a reactor, a power factor correction circuit having switching elements, capacitors and a reverse-current blocking rectifier elements, a smoothing capacitor for smoothing an output voltage of the power factor correction circuit to obtain a DC voltage, a pulse signal controller generating and outputting a pulse signal for turning on and off the switching elements, and a driver for receiving the pulse signal to drive a switching elements of the power factor correction circuit.

Abstract: In a load-side filter of an n-phase converter circuit arrangement, the capacitors are arranged in at least two n-phase capacitor groups, one of which is hard-grounded and the other of which is grounded with a high impedance via a grounding resistor.

Abstract: A method of reducing feedback action on a timely flow of current, which is drawn by a load from a network via rectifier, by active filtering of upper harmonics, which are superimposed on a network first harmonic, with a power factor corrector circuit with a pulse-width modulation of a switch signal which influences the current drawn from the network and flowing through a boost-converter, with the method including dividing a current path between the rectifier (2) and the load (10) in a plurality of parallel channels (It, Jt), and providing in each channel (It, Jt) a similarly active filter, with switch signals of both active filters having a substantially same pulse-width modulation and being phase-sifted relative to each other so that a reduced ripple of the total current, which results form cumulative superimposition of currents in separate channels, is produced at a network input (9); and an active filter for effecting the method.

Abstract: A technique for powering telephone lines using an unbalance current source and current sink; and a technique for improving attenuation/frequency distribution and return loss (impedance matching) of transformer-coupled wire-line communications circuits by using secondary series capacitance and an AC current pump signal source; and a generation of ringing voltage as positive voltage pulses with respect to a negative power supply voltage; and a technique for removal of AC power ripple by using an active linear floating filter for the purpose of powering telephone line circuits, and a technique for injection of real time tone samples into T1 transmissions circuits by use of a T1 framer idle code register.

Abstract: A single phase power supply for electric arc welders comprising: a full wave rectifier forming the input of said power supply; a valley fill power factor correcting circuit for controlling input current flow to the rectifier and creating an high crest factor intermediate voltage; a converter forming the output of the power supply for converting the intermediate voltage into a generally ripple free DC voltage; and, switching means in the converter for controlling the output voltage of the converter to a level in the general range of 20-100 volts for welding.

Abstract: The present invention is a method and apparatus of providing EMI filtering through the implementation of a voltage sense circuit that is used in conjunction with a power correction circuit in an electromagnetic (EMI) filter system. The apparatus comprises a filter that receives an alternating current signal, where the filter has an input terminal and an output terminal. The apparatus also comprises a power correction circuit having a voltage reference input terminal and an output terminal. A voltage sense circuit having an input terminal is coupled to the input terminal of the filter. The voltage sense circuit has an output terminal that is coupled to the voltage input terminal.

Abstract: A power supply includes a diode bridge rectifier. The diode bridge rectifier output provides direct current to a primary capacitor. A current-limiting resistor is connected in series with the rectifier output and the primary capacitor. The current-limiting resistor acts to limit inrush current to the primary capacitor when the power supply is turned on. A triac is coupled in parallel with the current-limiting resistor. When charged, the primary capacitor provides a primary signal and primary current to a switched load, which includes a first winding of a transformer and a load switching device. The transformer also has a second winding connected in series with the triac's gate terminal. When the primary signal reaches a satisfactory level, the load switching device switches the load, causing current transients in the first winding. The first winding current transients, in turn, induce current in the second winding and in the triac gate terminal.

Abstract: A unity power factor power supply includes a boost converter. The boost converter draws current in phase with the input voltage by operating as a current regulator having a current reference control signal which tracks the line voltage waveform. A sample and hold technique is utilized to accommodate single cycle step input compensation and to reduce harmonic distortion over a wide input frequency range.

Abstract: A device and method for reducing low frequency electromagnetic fields in an electric blanket includes an input, a rectifier filter, and a pair of closely spaced resistance wires. The input is connected to a 60 Hz AC power source to supply power to the electric blanket. The rectifier filter rectifies the input signal and filters out any high order components. The rectifier filter provides a filtered DC signal to apply across the paired resistance wires. In one embodiment, the device and method includes an output for connecting to a conventional electric blanket where the rectifier filter provides a filtered DC signal to the output.

Abstract: The alternative power system provides microprocessor grade, filtered output power capable of replacing standard NiCad battery packs in portable electronic devices. The invention makes use of capacitor banks comprised of capacitors having different values, whereby the individual capacitors act as individual filters to substantially eliminate all transients which are present in the source of power, which is typically provided by rechargeable batteries on a host system, such as a forklift or hand truck.

Abstract: Apparatus and method for eliminating cross conduction of self-driven synchronous rectifiers in power converters caused by non-idealized ringing of parasitic capacitances and inductors. In an exemplary embodiment, the apparatus includes synchronous rectifiers or some hybrid topology having at least one synchronous rectifier coupled to a damping circuit having at least one switching device. The switching device is activated (ON) at a time when at least one of the synchronous rectifiers is supposed to remain inactive (OFF). Accordingly, when the switching device is ON, the device effectively dampens any ringing present at the synchronous rectifier that may cause the rectifier to inappropriately transition ON. The damping circuit of the present invention utilizes the same signals present to control the synchronous rectifier(s) and requires no additional control circuitry. Additionally, the damping circuit dramatically improves the efficiency of self synchronous power converters and is topology independent.

Abstract: A PWM based converter including a Y-.DELTA., Y--Y transformer (or a .DELTA.--.DELTA., .DELTA.-Y transformer) wherein the Y-.DELTA. portion of the transformer phase shifts input voltage by 30.degree. with respect to the Y--Y portion of the transformer and thereby eliminates many low order supply line harmonics. The rectifier also includes two series connected PWM switching rectifiers, one rectifier receiving input voltages from the Y--Y portion of the transformer and the other rectifier receiving input voltages from the Y-.DELTA. portion of the transformer, and a controller for controlling the first and second rectifiers so as to eliminate low order harmonics on the supply lines that are not eliminated by the transformer. A capacitive bank is required between each rectifier and the transformer.

Abstract: A capacitor arrangement across a direct current bus provides a high ripple current capability and high capacitance at a low cost. The circuit is used in electronic power conversion devices such as electric motor drives and inverters. A combination of film capacitors and electrolytic capacitors are used in the circuit and are placed across the dc bus. The film capacitors carry substantially all of the ripple current, while the electrolytic capacitors provide the majority of the capacitance. A resistor and a diode are used to isolate the electrolytic capacitors from the ripple current. This results in a low cost compact bus capacitor configuration.

Abstract: An internal AC adapter which incorporates a space efficient EMI filter is positioned within a main chassis portion of a portable personal computer having at least one energy-demanding component also positioned within the main chassis portion. The internal AC adapter, which converts alternating current received from an alternating current main to direct current for transmission to the energy-demanding components, includes a first connector for electrically connecting the internal AC adapter to the alternating current main, a bridge rectifier circuit having an AC input side electrically connected to the first connector and a DC output side and a space efficient electromagnetic interference filter having an input side electrically connected to the DC output side of the bridge rectifier circuit and an output side. The bridge rectifier circuit converts alternating current received from the first connector to direct current for transmission to the electromagnetic interference filter.

Abstract: The present invention relates to a device for improving the harmonic ratio sent back onto the mains in a rectified power supply including a rectifying bridge and at least one capacitor connected to a first output terminal of the rectifying bridge. Between the second terminal of the capacitor and a second output terminal, a first charge path including a resistor is provided, as well as a second switchable discharge path, associated with means for switching on the discharge path only after the supply voltage has transmitted through a maximum.

Abstract: An air conditioning device is arranged such that an output voltage from a commercial power source is converted into a direct current by a rectifying circuit and a smoothing condenser. Thereafter, it is further converted into an AC voltage having a variable frequency by an inverter under the control of a microcomputer, thereby supplying it to a power compressor. Between the rectifying circuit and the smoothing condenser, an active filter is provided for shaping an input current to be an approximate sine wave almost in phase with an input voltage by switching a power transistor. The switching control section and the microcomputer for controlling the switching are activated independently by separately provided power sources. The switching control section supplies a high level signal when the active filter is a normal condition, and supplies a low level signal when the active filter is abnormal.

Abstract: An AC-to-DC power converter achieves greater than 80 percent power factor correction with greater than 75 percent efficiency using only one power switch, only one magnetic component, only one control loop, and a storage capacitor. The only magnetic component is a transformer having first primary winding, a second primary winding, and at least one secondary winding. During a first time interval of the period of the AC input current, the second primary winding is energized with energy previously stored in a storage capacitor. During a second time interval of the period of the AC input current, the first primary winding is energized with energy of an input current flowing through the AC input terminals. As a result, the AC-to-DC power converter drawns input current for an extended period of time before the point in time when the input voltage peaks and also for an extended period of time after the point in time when the input voltage peaks.

Abstract: To substantially reduce harmonic distortion and improve the power factor of n operating circuit for a fluorescent lamp, a smoothing circuit (G) is interposed between the outputs from a power rectifier (GL) and an inverter (WR) supplying the fluorescent lamp (L) with high-frequency energy. The smoothing circuit includes a two electrolytic capacitor (C1, C2)--three diode (D1, D2, D3) network, which is so connected, and the diodes so polarized that, during charging of the capacitors, a series circuit is established with one (D2) of the three diodes in series with the two capacitors. For discharge of the capacitors to supply the inverter when the rectified voltage is lower than the capacitor voltage, the two capacitors (C1, C2), through the other two diodes (D1, D3), are connected in parallel to supply the inverter. To substantially reduce harmonic distortion to less than about 30% and improve the power factor of the circuit to above 0.

Abstract: A power conversion circuit, in which a flyback converter is modified with additional elements to provide both dissipationless snubbing and also input ripple cancellation. This is achieved by appropriate connection of an additional winding to the isolating transformer, without any need for a second transformer. The configuration of the secondary is conventional, and the switching transistor is connected in series with the primary winding across DC inputs (taken e.g. from a full-wave-rectified line voltage). The additional winding is connected on the primary side, and preferably has a near-unity turns ratio with the primary which is the inverse of the coupling coefficient. However, the additional winding is not connected between the two DC inputs, but instead has one end coupled through an intermediate capacitor to the corresponding end of the primary, and the other end coupled through a capacitor to the negative DC input.

Abstract: A circuit arrangement for generating at least a DC output voltage (at 18, 19) from an at least substantially sine-shaped AC input voltage (at 2, 3) of a first frequency by a first rectifier arrangement (1) to which the AC input voltage can be applied (at 2, 3) and which has a DC output (4, 5) from which a rectified voltage is obtainable, a first inductance (6), a second rectifier arrangement (7) and a first filter capacitance (8) which, in this order, constitute a series arrangement connected parallel to the DC output (4, 5), a switched-mode power supply (9) having two input terminals (10, 11) with which it is arranged parallel to the first filter capacitance (8) and between which it includes a series arrangement of a second inductance (12) and a switching device (13) which is alternately switchable in the conducting state and in the blocked state at a second frequency and from which the DC output voltage(s) is (are) obtainable (at 18, 19), as well as a first control capacitance (23) by which the junction poi

Abstract: An internal AC adapter which incorporates a space efficient EMI filter is positioned within a main chassis portion of a portable personal computer having at least one energy-demanding component also positioned within the main chassis portion. The internal AC adapter, which converts alternating current received from an alternating current main to direct current for transmission to the energy-demanding components, includes a first connector for electrically connecting the internal AC adapter to the alternating current main, a bridge rectifier circuit having an AC input side electrically connected to the first connector and a DC output side and a space efficient electromagnetic interference filter having an input side electrically connected to the DC output side of the bridge rectifier circuit and an output side. The bridge rectifier circuit converts alternating current received from the first connector to direct current for transmission to the electromagnetic interference filter.

Abstract: An electrical power converter system having a power factor correction circuit and a switching power converter. The power factor correction circuit converts the AC line voltage into an unregulated DC voltage referred to as the PFC voltage, which supplies an unregulated DC input voltage to the switching power converter. The switching power converter converts the unregulated DC input voltage into one or more regulated DC output voltages. The PFC voltage automatically adjusts to an appropriate value for achieving the desired power factor correction, converter efficiency, and converter temperature. In a preferred embodiment, the value of the PFC voltage is adjustable in response to a control signal produced by a PFC control circuit. The PFC control circuit measures the peak value of the input line current to determine whether the power factor is acceptable. If the power factor is acceptable, the PFC voltage will be maintained at a relatively low value.

Abstract: A digital signal processor implemented monitoring circuit for detecting phase and magnitude disruptions in multi-phase alternating current input signals. A phase lock loop receives multi-phase alternating current input signals and provides one set of alternating current output signals in phase with a time average of the multi-phase alternating current input signals and provides a second set of alternating current output signals phase shifted in relation to the first set of output signals. In a three phase system the phase lock loop provides six alternating current signals. A demodulation circuit multiplies the first set of output signals from the phase lock loop circuit with the multi-phase input signals to produce demodulated sets of signals. An output circuit coupled to the demodulation circuit sums the first set of demodulated signals to provide a first source quality signal. The second set of demodulated signals is also summed to provide a second source quality signal.

Abstract: An electromagnetic interference reduction circuit incorporated into a pulse width modulator in a power factor corrector circuit, and which serves continuously to vary the operating frequency of the width modulated output of the pulse width modulator so that the fundamental component of said output is spread over a relatively wide bandwidth. The frequency of the width modulated output varies continuously in direct proportion to the voltage from a rectified alternating current sine wave voltage source in order to spread the electromagnetic interference in the circuit over a wide bandwidth.

Abstract: Power factor is increased and harmonic distortion is decreased in a boost circuit by varying the current drawn in phase with the ripple voltage from a rectifying bridge. The boost circuit includes a series connected inductor and switching transistor and the control electrode of the switching transistor is connected to a second inductor. The second inductor is magnetically coupled to the first inductor and provides feedback for sustaining high frequency oscillations in the boost circuit. A third inductor is magnetically coupled to the first and second inductors and to the control electrode of the switching transistor. The voltage from the third inductor is rectified and filtered to remove the high frequency pulses but not the ripple and the voltage is coupled to the control electrode of the switching transistor for changing the power consumed by said boost circuit in phase with the ripple.

Abstract: A power supply for use in electronic apparatuses is disclosed, and the power supply is provided with a switching control circuit for controlling the switching operations of a switching device of a rectifying portion, thereby making the switching device more efficiently operate. In the case where an over-voltage is supplied, the switching device is prevented from being damaged. There is added a tertiary coil in the transformer for inducement of a voltage, and a switching circuit is added to it, so that the switching control circuit should be switched in synchronization with a main MOS transistor which is connected to a primary coil of the main transformer. Thus, the switching operations of the switching device is made more efficient, and the switching device is protected, as well as making it possible to carry out a high density design. Therefore the power supply can be applied to all kinds of electronic apparatuses.

Abstract: A power factor control system for a rectifier is operative through the generation of estimators of control input parameters (a peak squared input AC voltage E.sub.m.sup.2 and load power) and by the use of these substantially ripple free signals controls a boost, buck, buck-boost, SEPIC or other related type converter at the input to the rectifier. The generation of these parameters allows the derivation of a programmed current i.sub.p used to control the wave form of the actual input current. The control procedure is based on a quarter cycle averaged power basis. The input power is derived from the rms values of the input voltage and current. Given the output power and its deviations in power due to load changes, the programmed current i.sub.p is determined by deriving an input conductance of the rectifier and combining it with the input voltage.

Abstract: A magnetic circuit with several magnetic components integrated on one or more common magnet cores is utilized in a current supply circuit known per se. The circuit comprises a transformer, the secondary winding ends of which are connected to uniform electrodes of a pair of rectifier diodes, the second electrodes of which are connected to one output terminal of the power supply circuit. Additionally, it includes two reactive components, and the first electrodes of the diodes are connected to the second output terminal of the power supply circuit via one of the reactive components. The number of turns of the two reactive components is essentially chosen to equal the number of secondary turns on the transformer. The two reactive components are positioned on each separate core part so that the resulting magnetic flux in common core parts substantially equals the difference between the magnetic flux of the two core parts, and the secondary winding of the transformer is positioned on the common core parts.

Abstract: Since a plurality of AC power supplies have output voltages controlled independently from each other and separate reference potential bus bars are connected with reference potential terminals of a plurality of DC power supplies connected with the different AC power supplies, respectively, power supply ripples contained in DC supplied to an electronic device can be reduced and it is possible to suppress generation of a beat produced by the fact that power supply ripples having frequencies deviated from each other interfere with each other. In this way fluctuations in the voltage of DC supplied to the electronic device are decreased and a working margin test for LSIs within the electronic device can be effected easily with a high reliability.

Abstract: A switching power supply converts DC to DC voltages. The switching power supply has multiple phase time delayed voltage generating circuits and a single switching power supply regulator circuit. The multiple phase time delayed voltage generating circuits are then synchronized with a pulse period of the switching power supply regulator circuit to achieve the conversion.

Abstract: In order to initiate the automatic regulation of the operating current of a current source in a power supply unit upon closing the operating load circuit connected to the current source, it is proposed that the current source is controlled by presetting the circuit parameters such that the current flowing in the operating load circuit upon closing the operating load circuit reaches a preset or desired value. The current regulation is brought into effect as soon as the difference between the effective value and the preset desired value of the current flowing in the operating load circuit falls below a predetermined threshold value. For this purpose, a regulation circuitry is provided, comprising a voltage regulator, a current regulator and a switching circuitry with a threshold value circuit. The switching circuitry generates a switching signal which effects the change from the initial voltage regulation to the subsequent current regulation as soon as the operating current exceeds a preset value.

Abstract: A circuit in a power system for suppressing an AC ripple superimposed on a bus signal on a bus includes a first circuit for producing first and second signals having a frequency substantially equal to the AC ripple frequency wherein the second signal is a phase quadrature of the first signal, a second circuit for combining these signals with a signal representing the bus signal having the AC ripple superimposed thereon so as to derive a control signal having substantially the same frequency and phase as the AC ripple, and a third circuit responsive to this control signal so as to substantially suppress the AC ripple on the bus.

Abstract: An improved commutation arrangement for an AC to AC or AC to DC energy converter circuit is disclosed. The improved arrangement uses turn-off capable commutation switches to enable modification of the operating waveforms in the cycloconverter. The modified waveforms include an operating concept wherein in lieu of always switching to the next lagging phase (as is done with conventional cycloconverters), an intervening switch is made to the leading phase when the output voltage is less than one-half of the maximum value. The disclosure includes mathematical consideration of source machine power factor, output waveform ripple content, interphase transformer characteristics, engine starting usage, and other refinements of the commutation arrangement.

Abstract: A power rectifying circuit (10) for converting an AC power signal to DC which includes a plurality of rectifiers (20) that receive power from a single AC power source (12). The AC power signal is power split amongst the plurality of rectifiers (20). Each power split signal is phase shifted by an incremental amount of phase shift and provided to on of the rectifiers (20). The rectified DC output of each rectifier is summed together and provided to a load (22) as DC power.

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.