Abstract: A power supply circuit having a higher power factor and decreased current crest factor. The circuit preferably comprises an input circuit for receiving an input AC voltage and rectifying this voltage and an output circuit for providing a DC output voltage. A pulse-width-modulation circuit intercouples between the input and output circuits and includes a controlled circuit adapted to pass input AC current in pulse-wide increments with the pulse-width varying in inverse proportion to the AC voltage. In this manner, when the instantaneous AC voltage is low, the pulse widths are wider and conversely when the voltage is high, the pulse widths are narrower. In one version of the invention, the pulse width modulation is carried out by a programmed variable ratio transformer.

Abstract: In a DC-DC converter of the type in which an inductance stores energy when a main switching transistor is turned on and releases the stored energy when the main switching transistor is turned off, a semiconductor active element is used as a flywheel element which is turned off when the main switching element is turned on, but is turned on to provide the path for the current established by the release of the stored energy, and the signal which is substantially in synchronism with the switching operation of the main switching transistor is applied to the control terminal of the semiconductor active element so as to cause it to turn on and off.

Abstract: Spikes occurring on an AC line and coupled through an AC to DC converter are substantially decoupled from a DC load of the converter even though the converter includes a supply transformer and a shunt electrolytic filter capacitor, by a circuit comprising a shunt network including a bidirectional breakdown means having a predetermined threshold conduction level with a dead band series connected with a capacitor. The capacitor is a low impedance capacitive reactance to high frequency components in pulses developed by the converter in response to the spikes, and a high impedance to ripple of the line derived by the converter. The high frequency components are supplied by the breakdown means to and through the capacitor to momentarily interrupt the flow of current from the converter to the load when the pulses are derived. A low pass filter connected in series with the shunt network and the load has a cut-off frequency lower than the ripple frequency.

Abstract: Disclosed is an electrical power system adapted to receiving power from a source of alternating current, typically a small alternator, and supplying a direct current potential to a load. This power system includes two stages, the first stage comprising switchable rectifying devices such as silicon controlled rectifiers which interact with the impedance of the alternator or other source of alternating current power as a switching regulator to create an intermediate direct current potential.The second stage operates from this intermediate direct current potential to produce a slightly lower output voltage, and creates a more accurate regulation than is possible with the first stage alone, the second stage greatly reduces ripple and high frequency noise components contained on the output of the first regulator stage. The second stage serves as an active low pass filter tuned to a desired DC voltage.

Abstract: A high voltage converter converts an incoming high frequency pulse voltage to a direct voltage at a level which can be varied by varying the pulse width. The converter contains a transformer (T) with its primary side (p) connected to a pulse source (U) and to a controllable switch (K). The secondary side of the transformer is divided into two sections (s.sub.1, s.sub.2). One section (s.sub.1) is connected to a rectifier in the form of a conventional voltage doubler circuit (D1, D2, Cd1, Cd2) with capacitors in parallel with the secondary winding sections (s.sub.1, s.sub.2). The other section (s.sub.2) is connected to a rectifier bridge (D3-D6) and a smoothing filer (L.sub.f, C.sub.f). The converter output is the doubler circuit output in series with the smoothing filter output.

Abstract: A-C energy, from an a-c power system, is converted by a phase-controlled SCR rectifier bridge, which is followed by a series-connected filter choke and a shunt-connected filter capacitor, to d-c power for delivery via a d-c bus to a load, such as an inverter and an a-c induction motor driven by the inverter. When there is a decrease in load demand, for example when the motor speed is to be reduced, fast speed control is obtained by regenerating power back into the a-c power system from the load. Power flow through the d-c power supply is reversed by means of a switching network, interposed between the filter choke and capacitor, having a pair of reverse SCR's for cross-coupling the positive and negative lines of the d-c bus. When the reverse SCR's are fired into conduction, the connections between the filter capacitor and the bridge's output terminals are effectively reversed, thereby facilitating power flow from the load to the a-c power system.

Abstract: To provide a power rectifier for connection to an a-c power network which has low ripple at the d-c output, and low harmonic content at the a-c side, particularly for feeding a d-c - a-c inverter frequency generator providing output in the audio or low supersonic range for supply of gas discharge or fluorescent lamps, a wave-shaping network is connected to the a-c side of a standard bridge rectifier unit such that the a-c power applied to the rectifier is of approximately trapezoidal or rectangular or square-wave shape; a suitable network is the combination of an inductance (D) and a storage capacitor(C1) in a T-network or in a series resonant circuit, in which the quadrature VA of the choke (D), at network frequency, is about 60% of the power to be supplied by the rectifier, with a capacitor (C1) in a T-network configuration of such value that the resonant frequency of the L/C circuit is about 2.2 to 2.6 times network frequency or equal to network frequency, when in a series resonant circuit.

Abstract: The disclosed dual mode direct current power supply comprises an AC transformer, a pair of DC output terminals, and first and second rectifier-filter circuits connected in parallel between the transformer and such terminals; the first circuit comprising first rectifiers for producing first rectified pulses, a first capacitor adapted to be charged to the peak voltage of such pulses, and an electronic voltage regulator including a series transistor; the second rectifier-filter circuit including second rectifiers for producing second rectified pulses, a choke input filter including an inductance and a second capacitor adapted to be charged through the inductance to the average voltage of the second pulses, and a series diode; the regulator causing the transistor to be nonconductive at high DC output voltage and then conductive increasingly in response to decreasing output voltage whereby the first rectifier-filter circuit supplies an increasing share of the load current.

Abstract: A circuit for use in a multiphase regulated supply to provide regulation of the ripple current contained in the filtered d.c. output signal of the supply. The supply regulates its output voltage and/or current by controlling the conduction time of the switching elements contained in the rectifier portion of the supply. The switching element conduction time is controlled by controlling the generation of firing pulses to the switching elements as a function of an error control signal which is equal to a first error signal. This signal is equal to the amount by which the actual value of said voltage and/or current deviates from a reference value of said parameter. When the ripple regulation circuit is included in the supply, a second error signal is generated which represents the deviation of the d.c. value of the ripple from a predetermined reference.

Abstract: A power source system, which comprises a converter for converting AC power on an AC bus into DC power, a damped filter connected between the AC bus and ground and including a capacitor and an inductor, a diode-rectifying circuit for taking out and rectifying fundamental and harmonic waves produced across the inductor in the damped filter and a circuit for connecting a DC output circuit in the diode-rectifying circuit in series with a DC output circuit in said converter, and in which the rectified output is regeneratively added to the output of the converter.

Abstract: A switching regulator circuit for utilization with power supplies supplying a high DC output current including a plurality of control rectifiers and inductive reactors with sequential gating of the rectifiers at regular intervals for providing overlapped output current pulses from the reactors. An output circuit receives the rippled current comprised of the overlapped output current pulses for reducing the ripple therein. The output circuit includes a choke in series with the output which induces phase shift between the rippled current and the output current. A sensing winding associated with the choke eliminates the phase shift voltage for forming a feedback signal as an input to a control circuit. The control circuit utilizes the feedback signal to control the rate at which the rectifiers are gated sequentially.

Abstract: Circuit for the compensation of harmonic currents in a network, including a wideband highpass filter having a choke connected in parallel with a damping resistor and a capacitor connected in series therewith, and a harmonic converter connected to the highpass filter.

Abstract: AC to DC converters used in high-voltage direct-current power transmission lines produce objectionable harmonics. The composite filter herein described is actively tuned for the eleventh and thirteenth harmonics in addition to providing a low impedance path for the higher order harmonics, thereby eliminating such undesired harmonics so that they will not be transmitted over power lines where they can cause telephone interference, undesired heating of electrical equipment and other difficulties.

Abstract: An electronic power supply utilizes a full wave bridge rectifier circuit whose alternating current voltage source is derived from a multi-primary and multi-secondary winding transformer whose windings are selectively disposed in series or parallel circuits, thereby enabling the apparatus to be effectively employed on a wide variety of A.C. voltage sources. Two adjacent legs of the bridge rectifier employ S.C.R.'s gated simultaneously symetrically by pulses obtained from a unijunction transistor driven by the output of an operational amplifier whose input terminals are coupled to voltage and current sensing networks located at the output terminals of a filter coupled to the D.C. side of the full wave bridge.

Abstract: A high power factor AC to DC converter circuit includes a rectifier circuit coupled to an AC potential source and providing a full-wave rectified pulsating DC potential to a switching regulator circuit with a radio frequency current filter connected in circuit with the rectifier and switching regulator circuits to provide a pulsating DC current in phase with and of at least 50% duration of said pulsating DC potential whereby a power factor of at least 90% is effected.

Abstract: An active filtration system is described which may be particularly useful for filtering undesired harmonics of the fundamental AC frequency produced by AC to DC or DC to AC conversion. The filtration system of the invention produces currents of a phase, frequency and magnitude for injection into the AC system such that the undesired harmonic currents to be filtered sum with the injected currents giving a net zero current at the undesired harmonic frequency. The system can incorporate existing passive filtration elements and provides a high-impedance parallel-filtration network to prevent the filteration system from acting as a "sink" for the ambient harmonics generated elsewhere in the AC system. Because the frequency, phase and magnitude of the injected currents are controlled, the filter of the invention remains highly effective even when these quantities and the filter component values vary.