Abstract: A controlled rectifier equipment with sinusoidal waveform supply current is provided, in which equipment an inexpensive AC current transformer can be used as an AC current detector. The AC current transformer is used as an AC current detector. A DC component eliminating circuit including a low pass filter which cuts off the frequency component of commercial AC power supply is arranged on the line between an current controller in a current control system and a modulation circuit in the conduction control signal generating circuit. The circuit is formed so that a DC offset component which is generated in a controlled rectifier equipment may be eliminated.

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: In a pulse width modulation-controlled, switched bridge, DC converter, the phase angle (44, 45) of the AC mains (4) is provided without sensing the voltage thereof, by a phase-locked loop (47) having one input (75) derived (126) from the in-phase voltage command Vde* (61) and another finit (77) approximating the line frequency; the phase-locked loop is initialized at a phase angle &thgr;init(76) equal to the arctangent (124) of the in-phase Vdest, and quadrature Vqest representation of estimated line voltages ere, ese, ete (119-121) derived during an initialization cycle from reconstruction of the fundamental component of the AC main currents at a phase angle (93) changing with said frequency. Reconstruction includes providing the discrete Fourier transform (DFT, 81) of signals indicative of currents (37) in the AC mains and the inverse DFT (122) of the resultant Fourier coefficients eia, eib.

Abstract: To enable a relatively constant output voltage at a DC/DC converter of a field device during a predictable time after shut-down of energy supplied to the DC/DC converter there is proposed a load voltage controller having a comparison unit adapted to compare the load voltage signal (Uo) with an externally supplied load voltage reference signal (Uref). When the load voltage (Uo) exceeds the load voltage reference signal (Uref) an energy buffer stores supplied energy for subsequent resupply to the load of the field device.

Abstract: A modular DC power distribution system. A physically discrete input conversion module is utilized for converting a source AC signal to a high voltage DC signal. Multiple universal mounting sites are provided in a power supply backplane for engaging one or more of such input conversion modules. Within the power supply backplane, the high voltage DC signal is delivered to a DC distribution bus. A physically discrete DC step-down module is utilized for converting the high voltage DC signal from the DC distribution bus to a point-of-load DC signal distributable to application boards. The power supply backplane includes multiple universal mounting sites wherein one or more DC step-down modules may be installed or removed. In another embodiment, the DC power distribution system of the present invention includes a pre-charge system for permitting the input conversion modules and the DC step-down modules to be hot plugged into the power supply backplane.

Abstract: A power conversion system utilizes an inductive device having a magnetic core formed of a plurality of wires that extend through the inductive device, and beyond its electric windings. The ends of the wires are formed around the electric windings, meet, and are connected together enveloping the magnetic core and windings forming a complete magnetic circuit. The inductive device may be a transformer used in a power supply, inverter, or other device with two or more windings, a choke coil with only one winding used in a ballast, power supply, inverter, or other inductive device. The power conversion system may further include a rectifier, a filter, and a regulator a so called analog system or components as in a switch mode system.

Abstract: The invention relates to an apparatus for initial charging of the output capacitors of a three-phase three-point pulsed rectifier system. According to the invention, a thyristor is arranged in each phase between the input terminal and is connected in the current flow direction to the anode of the freewheeling diode, and an initial charging path is connected in parallel with this thyristor. The circuit for actuating the thyristor is activated after completion of the initial charging; the reference voltage is applied to the negative input of the comparator.

Abstract: The electrophoresis apparatus comprises rectifier (A) which rectifies an AC current from a universal AC power source and outputs a rectified wave, an electrophoresis cell and an electric controller which applies an electric output from the rectifier (A) to a carrier disposed in the electrophoresis cell, the elastic controller comprising a controller (3) for indirectly controlling, in accordance with external inputs, a driving section (6) which controls an electric output from the rectifier circuit. The electrophoresis cell unit defines a recess for receiving the electric controller, and a cover is positionable over the electrophoresis cell unit. The cover includes a cover terminal, where the cover and cover terminal are shaped to electrically connect an output terminal of the electric controller to an input terminal of the electrophoresis cell unit when the cell covers the electrophoresis cell unit.

Abstract: In a downconverter for supplying a DC current to a lamp, power feedback is achieved by adding a high frequency-operated switch and a capacitor to the topology. The power factor is improved thereby.

Abstract: For use with a power plant having a rectifier and a backup battery coupled to a variable load, a system for, and method of, assessing a capacity of the backup battery. In one embodiment, the system includes: (1) a controller, coupled to the rectifier, that controls an output current of the rectifier to maintain a discharge current of the backup battery at a substantially constant level and (2) a voltage sensor, coupled to the backup battery, that measures a voltage of the backup battery.

Abstract: A controller or a method for regulating a non-isolated power factor corrector and a power factor corrector employing the controller or the method. The power factor corrector is adapted to provide a DC output voltage at an output thereof. The power factor corrector has first and second power switches, coupled to an input thereof, that receive unrectified AC power. In one embodiment, the controller includes: (1) a sensor, coupled proximate the input, that senses a polarity of the unrectified AC power and (2) a drive circuit, coupled to the sensor, that: (2a) closes the first power switch and modulates the second power switch to regulate the DC output voltage when the polarity is negative, and (2b) closes the second power switch and modulates the first power switch to continue to regulate the DC output voltage when the polarity is positive.

Abstract: An output voltage of a rectification smoothing circuit is compared with a reference voltage. When a reduction in the output has been detected, an A/D converting circuit converts a result of the comparison which is negatively fed back by an output voltage feedback circuit to obtain a control signal for a bidirectional switch element inserted into a primary side of a transformer so as to turn ON or OFF synchronously or asynchronously with a commercial power supply via an intermittent control circuit.

Abstract: A method of controlling a supply of electric power to an electric load and a circuit thereof are disclosed. The circuit includes a control voltage generating part means for generating a control voltage which decreases over time, an amassing part for amassing the control voltage upon a voltage signal increasing over time and discharging the amassed voltage nearby a zero crossing point of AC voltage from the AC source in order to generate a saw-tooth wave, a trigger signal generating part for generating trigger signals based on the saw-tooth wave, wherein the phase angle of the trigger signals varies depending on the saw-tooth wave, and a switch part for supplying electric energy from the AC power source to the electric load in response to the trigger signals. Therefore, electric power being supplied to an electric load fades out.

Abstract: In a multi-phase AC/DC converter provided with an artificial neutral point a voltage sensing circuit is provided. The voltage sensing circuit comprises three small windings connected to a first common point and to three impedances. In the circuit, the voltage between the first common point of the windings and a second common point of the impedances is measured. The voltage is indicative of the current flowing in the artificial neutral point. By using such a circuit the current sensing in the neutral point can be simplified and the multi-phase AC/DC converter made at a lower cost.

Abstract: A multi-motor drive in which the resonance existing between one or more output filter capacitors of a current source inverter and an a.c. induction motor is reduced. The inverter features a switching pattern generator which controls the power switches of the inverter based on a reference current. A control loop, connected to the switching pattern generator, measures the load current or voltage and generates a nominal reference current based on an error therein; determines a damping current based on the voltage at the terminal; and determines the reference current supplied to the switching pattern generator by subtracting the damping current from the nominal reference current. The invention essentially simulates the use of a physical damping resistor connected in parallel with each output filter capacitor, but without the corresponding energy loss.

Abstract: A switching regulator device for charging applications includes a transformer (18) which receives an AC input signal from an AC source (12) which is then rectified with a bridge rectifier (24). A regulation control circuit (26) is provided for regulating the output level of the bridge circuit (24) to a load (20). The regulation circuit (26) includes a switching element (62) which is operable to draw current from the AC source (12) in a periodic manner. The on/off duty cycle of the control to the switching element (62) will allow energy to be stored in a leakage inductance (36) of the transformer (18). The transformer (18) therefore comprises the switching inductance of a switching power supply with the leakage inductance (36) designed to provide adequate regulation for the voltage and current supplied to the load (10).

Abstract: An ac/dc converting circuit adapted to output a direct voltage that is higher than a full wave rectified voltage of an alternating input voltage is provided which includes an alternating current filter, and a condenser with a positive electrode and a negative electrode coupled to a dc output side of a full wave rectifying circuit. The full wave rectifying circuit includes a switching portion having upper and lower arms each having a semiconductor rectifying element and a self-commutated semiconductor switching element, and a rectifying portion having upper and lower arms each having a semiconductor rectifying element. The semiconductor rectifying elements in the upper arms of the full wave rectifying circuit has a common cathode coupled to the positive electrode, and the semiconductor rectifying elements in the lower arms has a common anode coupled to the negative electrode.

Abstract: A power conversion apparatus includes a current component control section which outputs q axis and d axis negative-sequence components and q axis and d axis positive-sequence components based on a detected current value or a voltage value, a current component control which compares a current component with the current instruction value from an instruction value generator and outputs to an adder/subtractor the result, a converter converting a control signal output from the adder/subtractor into three-phase components, and an adder adding these three-phase components to respective phases and outputting the result to a power conversion section.

Abstract: A multistandard rectified supply circuit comprises, across a full wave rectifying bridge, at least one storing element associated with a charge path comprising first unidirectional conductive elements of a first polarity and with a discharge path comprising second unidirectional conductive elements of a second polarity so that the storing means is differently charged and discharged. A switch cancels the effect of at least one of the first and second unidirectional elements so that the storing element is charged and discharged through a same path.

Abstract: A lighted water globe comprises a base having a hollowed interior and a water filled glass dome arrangement supported on the base. The glass dome arrangement has a lower portion accessible within the base interior and the lower portion has a window through which light may pass. A bundle of fiber optic elements is disposed within the glass dome arrangement, the fiber optic elements terminating at an end of the bundle adjacent the window. A light source is disposed in the base interior directing light to the bundle end through the window. A music box movement provides mechanical power to rotate an effects wheel to dynamically alter the light as it passes from the light source to the window and on to the bundle end of the fiber optic elements, creating interesting and changing lighting effects. The internal objects within the water globe may be made from a material which glows in the dark.

Abstract: An ac/dc converting circuit adapted to output a direct voltage that is higher than a full wave rectified voltage of an alternating input voltage is provided which includes an alternating current filter, and a condenser with a positive electrode and a negative electrode coupled to a dc output side of a full wave rectifying circuit. The full wave rectifying circuit includes a switching portion having upper and lower arms each having a semiconductor rectifying element and a self-commutated semiconductor switching element, and a rectifying portion having upper and lower arms each having a semiconductor rectifying element. The semiconductor rectifying elements in the upper arms of the full wave rectifying circuit has a common cathode coupled to the positive electrode, and the semiconductor rectifying elements in the lower arms has a common anode coupled to the negative electrode.

Abstract: A three-phase controlled rectifier bridge for converting alternating current to direct current includes six segments for each of the positive and negative polarities of each of three AC phases. Each of the segments has a semiconductor controlled rectifier element responsive to a control signal to control current conduction within the segment. A conduction monitor, which is provided for each of the AC phases, monitors a corresponding one of the AC phases to provide a conduction monitor signal. A first shunt current sensor senses current of the segments for the positive polarity of the AC phases and provides a first current signal. A second shunt current sensor senses current of the segments for the negative polarity of the AC phases and provides a second current signal.

Abstract: An apparatus for converting three phase AC supply line voltages to DC voltage on a DC bus, the apparatus including a master converter subsystem and at least one slave converter subsystem wherein each subsystem includes a current regulator, a PMW modulator and a converter, the master converter linked to the supply lines and the slave converter linked to the supply lines via intermediate lines, each regulator receiving a current command signal and generating modulating signals, each modulator using a carrier signal and modulating signals from a corresponding regulator to generate control signals to control a corresponding converter, the intermediate lines linked to a common mode choke for essentially eliminating common mode currents in the intermediate lines.

Abstract: In a direct-current power supply system, an alternating current outputted from an AC power supply is converted by a second diode bridge circuit into a direct current. The direct current is smoothed by voltage doubler capacitors and a smoothing capacitor. A reactor is inserted into an input side of the second diode bridge in series. Detecting circuit is operatively connected to the AC power supply for detecting a zero-crossing point. When the zero-crossing point is detected by the detecting circuit, control means is adapted to firstly switch a switching element on for a first predetermined period of time and, after a predetermined delay period of time has passed since the switching element is firstly switched on, adapted to secondly switch the switching element on for a second predetermined period of time.

Abstract: A boost converter having multiple L-C branches and a method of operating the same. The boost converter includes first, second and third phase inputs and an output. In one embodiment, the boost converter includes first and second switches coupled between corresponding rails of the output. The boost converter also includes first, second and third capacitors that form first, second and third L-C series branches, respectively, with a first inductor. The first, second and third L-C series branches are coupled between the first, second and third phase inputs, respectively, and a node between the first and second switches. The first and second switches cooperate progressively to employ a voltage across the rails less a voltage across the first, second and third capacitors to discharge currents through the first inductor and thereby reduce input current total harmonic distortion (THD) on all three of the phase inputs.

Abstract: An internally programmable power supply for use with an AC input voltage supplied to an input terminal for producing a DC output voltage. At least one power conversion module is providing having an input and an output. The input of the at least one power conversion module is adapted to be connected to the AC input. The at least one power conversion module includes rectifier means for converting the AC voltage to a DC voltage and a filter to provide the DC output voltage. A digital controller is connected to at least one power conversion module and includes a feedback network having a plurality of feedback components for forming a feedback loop. A microprocessor is provided and a keyboard accessible to the user is coupled to the microprocessor. A logic device is coupled to the microprocessor and is provided with a logic programming interface.

Abstract: Various DC/DC converter topologies having improved electromagnetic interference (EMI) characteristics and methods of providing dual DC outputs with such converters. One embodiment of one DC/DC converter having dual, EMI-quiet outputs includes: (1) a first subcircuit, having a series-coupled first switch, first inductor and first capacitor and an output across the first capacitor, coupled between first and second DC input rails, (2) a second subcircuit, having a second switch, second inductor and second capacitor and an output across the second capacitor, coupled between the first and second DC input rails in anti-parallel with the first subcircuit, (3) a first diode coupling a node between the first switch and the first inductor and a node between the second inductor and the second capacitor and (4) a second diode coupling a node between the first inductor and the first capacitor and a second node between the second switch and the second inductor.

Abstract: A low power high efficiency power supply provides a high voltage level output, which can be used to drive a variety of devices. The power supply uses controlled feedback to a comparator, which in turn drives an AND gate logic device. The comparator drives the AND gate logic device to gate an input clock signal the output of the AND gate logic being supplied to a resonant circuit that is at or near the resonant frequency of the input clock signal. The output of the resonant circuit is rectified to provide the final voltage output. The final voltage output is attenuated and supplied as feedback to the comparator.

Abstract: A three-phase boost converter having wye-connected input capacitors and a method of operating the same. The boost converter includes first, second and third phase inputs and an output. In one embodiment, the boost converter includes first, second and third inductors coupled to the first, second and third phase inputs, respectively, and operable in a discontinuous conduction mode (DCM). The boost converter further includes first and second switches coupled between corresponding rails of the output. The boost converter still further includes first, second and third capacitors coupled between the first, second and third phase inputs, respectively, and a node between the first and second switches. The first and second switches cooperate progressively to employ a voltage across the rails less a voltage across the first, second and third capacitors to discharge currents through the first, second and third inductors, respectively, and thereby reduce input current THD on all three of the phase inputs.

Abstract: A rectifier control system with rectifiers connected in parallel operates constantly by ensuring balance between the rectifiers with respect to output voltage and current. The rectifiers apply a DC voltage to a single DC bus. Current detectors associated with the rectifiers detect the bus current flowing through the DC bus. Voltage control circuits associated with the rectifiers control the DC voltage to coincide with a voltage command value. Command value generating circuits associated with the rectifiers correct the voltage command value with a signal proportional to the detected bus current or a signal obtained by integrating or amplifying the bus current with an amplifier having a first order lag characteristic.

Abstract: A programmable, low-current voltage source for small-signal electronic equipment, such as portable cellular telephones, is achievable by generating and applying a bias voltage and a reference voltage across a voltage divider circuit. Consequently, a low-current output voltage is generated at the center junction of the voltage divider circuit. Adjustment of the low-current output voltage level is accomplished by adjusting either the bias voltage level and/or the reference voltage level. The adjustment of the bias voltage level and/or the reference voltage level, in turn, is controlled by a programmable, microprocessor-based waveform generator.

Abstract: A power converter including a star converter module network and a star resistive network. A feedback network monitors the voltage difference between the nodes of the star converter module network and the star resistive network, and provides a signal for each phase of an AC supply corresponding to the voltage difference. An output sensing means senses the output voltage across output terminals and produces a demand signal based on a comparison of the output voltage with a required value. A controller produces a control signal based upon this comparison for each phase, and the control signal is used to control a corresponding converter module. Applications include power converters for supplying an isolated supply from a multi-phase main supply not having a neutral connection.

Abstract: An AC-DC converter includes an adjusting unit 13 which operates to zero the difference between a DC output voltage instruction value and a DC output voltage detection value; and a modulator 16 which compares a carrier wave based on an output signal of the adjusting unit 13 with a modulating wave to output drive pulses, a switching element 3 is turned on and off with the drive pulses to provide a DC output voltage which is higher than a full-wave rectification voltage of an AC input voltage. In order to obtain the carrier wave, the AC-DC comprises further includes an AC input voltage polarity detector 7, a PLL circuit 11, and a multiplier 14 for multiplying the sine wave by an output signal of the adjusting unit 13.

Abstract: A multi-output switching power unit which can substantially prevent an output power supply of an auxiliary output power circuit from dropping significantly when a load a is light and which has a reduced loss in the output path. A voltage up capacitor 20, a first diode 21, a second diode 22 and a series regulator 13 are provided in the auxiliary output power circuit 9 including a choke rectifier circuit 4. When the load a is light and an output voltage V2 of the auxiliary output power circuit 9 drops to below the predetermined voltage of the series regulator, the series regulator 13 is put into a conductively connected state.

Abstract: An AC-to-DC converter and regulator normally receives power from an AC utility line and provides a stable DC output to a load, such as the power amplifier and transmitter of a cell site. The DC output, or a separate dedicated output from the converter, is used to charge a backup battery when AC power is available. If AC power is interrupted, the backup battery provides power to the load by way of a separate DC-to-DC differential converter. The battery is connected in parallel with the differential converter input, but in series with the differential converter output. Thus, the differential converter receives operating power from the battery, and outputs a voltage which is summed with the battery output to drive the load. A control circuit for the differential converter senses the voltage provided to the load, and supplies a signal to the differential converter to adjust its output as necessary to maintain the optimum aggregate output to the load.

Abstract: A three phase input, boost power supply comprises first, second and third rectifiers for respective phases of the three phase input. First, second and third boost inductors are interposed between the first, second and third rectifiers, respectively and respective phases of said three phase input. A low pass filter is interposed between the boost inductors and the three phase input. A chopping switch is connected to an output of at least one of the rectifiers in parallel with a load to boost a voltage of the load. A current sensor is connected between the rectifier output and the load. The switch is activated in response to the current sensor sensing approximately zero current flow. The subsequent rate of current rise is proportional to the magnitude of the input voltage. The switch is deactivated based in part on a comparison of the load voltage to a reference voltage. Thus, the input current for each phase has nearly unity power factor, even when one phase drops out.

Abstract: Methods, circuits, and kits for converting battery powered smoke detectors to AC power include a power converter which converts standard household AC voltage to a DC voltage suitable for use by a battery powered smoke detector and a battery clip connector for connecting the power converter to the battery clips of a battery powered smoke detector. According to one embodiment of the invention, a light emitting diode is coupled to the battery clip connector to indicate the presence or absence of DC voltage at the smoke detector. According to another embodiment of the invention, several battery powered smoke detectors are coupled to a single power converter. In yet another embodiment of the invention, several battery powered smoke detectors are provided with an AC power supply having an automatic battery back-up power supply. Preferred aspects of the invention include: providing the battery backed-up AC power supply with a battery tester and providing fuses for each smoke detector and for the battery.

Abstract: An improved power factor DC power supply in accordance with the present invention (100 or 200) employs a power factor correcting network (120), a full-wave rectifier means (122), a pair of filter capacitors (124 and 126), and three current steering diodes (128, 130 and 132). The power factor correcting network (120) includes both an inductor means (136 and 240) and a capacitor (138), the combination configured to improve the power factor DC power supply (100 or 200) presents to the AC power-line (102) by reducing the level of harmonic currents the DC power supply generates on the AC power-line. The filter capacitors (124 and 126) are configured with the current steering diodes (128, 130 and 132) such that the filter capacitors are charged in series and discharged in parallel.

Abstract: A transient voltage protection circuit includes a normally closed switch connected between a rectifier circuit and a DC to DC converter. This switch is caused to switch to a current limit state when the voltage input to the DC to DC converter exceeds a first predetermined value, thereby protecting the DC to DC converter from voltages that exceed the converter's operational limits. The switch is returned to its normally closed state when the voltage input to the converter drops below a second predetermined lower value. A capacitor connected across the input terminals of the converter is charged up when the switch is closed and functions to supply power to the DC to DC converter when the switch is in its current limit state.

Abstract: An AC-DC converter which allows an input current of an input AC power source to have harmonic currents of reduced levels and which supplies a stabilized output DC voltage to a load is realized by a simple circuit configuration. The converter has: a converter circuit consisting of a choke coil which receives a rectified voltage from a rectifying circuit, a switch element, and a diode; a smoothing capacitor which smooths the output voltage of the converter circuit and supplies the smoothed voltage to a load; and a control circuit consisting of a current detection circuit, a voltage detection circuit, and a pulse-width control circuit. In order to stabilize the output voltage, the switch element is turned on and off so that the peak value of the input current of the converter circuit is limited in a DC-like manner, thereby allowing the input current to have a trapezoidal waveform.

Abstract: A circuit for driving a gas discharge lamp load and including an EMI and transient supply filter coupled to an input source, a rectifier coupled to the filter, a power inverter coupled to the rectifier, a load including a transformer coupled to the power inverter, and a control circuit coupled to the power inverter and the load. A feedback circuit couples the load transformer to the AC side of the rectifier to create a path for transferring a feedback voltage over the rectifier to cause the rectifier to conduct current over a substantive portion of each cycle of the AC input voltage.

Abstract: A power source device minimized in size with required number of switching and energy-storing elements for a power conversion reduced is provided by connecting a first energy-storing element through a first switching element in parallel to a power source, connecting a load circuit having a parallel connection of a voltage stabilizer and a load through a second switching element in parallel to the first energy-storing element, connecting an ON/OFF controller to the first and second switching elements for their controlling, and providing a voltage controller including a second energy-storing element and further switching elements for controlling an output voltage to the load circuit through switching operation of the further switching elements.

Abstract: Circuit arrangement for an inductive load with a rotor and at least one winding, a DC-voltage intermediate circuit and at least one switchable semiconductor rectifier of a power stage connected to the winding for passing a current therethrough, and a current regulator subject to hysteresis for regulating the current, includes control electronics connected to the current regulator for prescribing the hysteresis and the frequency of the current regulator, respectively, as a function of the current.

Abstract: The present invention is directed to a novel converter for interposition between an AC power source and a DC load capable of maintaining a substantially unity power factor independent of the impedance of the load. According to the invention, the converter has rectifying circuit to provide DC power to a DC power output circuit from an AC source, circuit for varying the impedance seen by the AC source in the DC output circuit, and circuit responsive to a shift in AC input current away from an in-phase relation with the voltage of the AC source under loading of the DC power output circuit for controlling said impedance varying circuit in a direction to return the AC current towards in-phase relation with the AC voltage. More particularly, according to the preferred form of the invention, the circuit for varying the impedance seen by the AC source in the DC output circuit includes a resonant circuit interposed between the rectifying circuit and the DC output circuit and connected to deliver DC power thereto.

Abstract: In an AC-powered power supply with a bipolar controller V controlling the instantaneous value of a control quantity measured by a sensor F.sub.1 to a predetermined setting within a deviation of less than 0.1% at 1 Hz via the output DC current I.sub.o, and with an adjustable rectifier EQ followed by a charging inductance L.sub.1 and a filter capacitor C.sub.1, whereby the output of controller V is electrically connected to the output line of the power supply, the output of controller V is AC-decoupled from filter capacitor C.sub.1 by a decoupling inductance L.sub.2, two potentials V.sub.o +V.sub.1 and V.sub.o -V.sub.2 are supplied to controller V, and a sensor F.sub.2 is provided for the output current I.sub.2 of controller V, which feeds an output signal to a control unit CTR which controls rectifier EQ in such a way that the mean value of output current I.sub.2 of controller V is regulated to a minimum value.

Abstract: A power supply is adapted to be connected to single or multiple phase power lines providing alternating current, for delivering power to a load. The supply has an energy storage device for storing and then delivering electrical energy to the load. An inductive system is adapted to be coupled to the power lines for inductively storing and discharging energy. A switching system is coupled to the inductive system for switching a flow of bidirectional current through the inductive system to alternately (a) store energy in the inductive system from the power lines and (b) convey energy from the inductive system and the power main to the energy storage device. Also included is a controller coupled to the switching system for operating it at a repetition rate exceeding that of half cycles of the power lines.

Abstract: A circuit is provided for generating a current that is a harmonic of the frequency of the utility system and which is of a selected amplitude and phase to reduce the total harmonic distortion of a system that converts alternating current to direct current, or vice versa. The DC signal is sampled and by controlling switches, a sinusoidal current at the desired harmonic is generated, and is provided to a neutral of a transformer that injects this current into the multiphase AC system used by the utility in a very low cost, easily controlled, and highly effective manner. In a second embodiment, the injection current is provided to a common junction of a magnetic device.

Abstract: A full wave rectifier includes an amplifier having a minus input, a plus input and an amplifier output; an input resistor connected between a circuit input and the minus input; and a current bridge having an output terminal connected to the circuit output, a first terminal connected to the minus input and a second terminal connected to the amplifier output. The current bridge includes a first current mirror circuit and a second current mirror circuit. The first current mirror circuit includes a first current source and a second current source, a source end of each current source of the first and second current sources being connected to the first terminal, a drain end of the first current source being connected to the second terminal and a drain end of the second current source being connected to the output terminal.

Abstract: An arrangement is provided for accurately sensing the source voltage of a high-impedance source while supplying a variable burden. A current-sensing element is connected in series with a load circuit across a high-impedance source. The load circuit includes a variable burden load. A shunt regulator is connected with the variable burden load and is arranged to operate so that the combination of the shunt regulator and the variable burden present a controlled, nearly constant burden to the high-impedance source. The source voltage of the high-impedance source is sensed via the voltage across the series current-sensing element. While the output voltage is directly proportional to the burden, the output current is essentially unaffected by small variations in the burden.

Abstract: After an AC voltage was rectified and smoothed, it is stepped up by a chopper circuit. Another winding is magnetically coupled to a choke coil of the chopper circuit so as to have the same polarity. An inductance for adjusting a current is connected serially with another winding. A current of a phase opposite to a phase of a current flowing in the choke coil is generated in another winding, thereby setting off a ripple current flowing in an input smoothing capacitor.