Abstract: An electronic method and apparatus are described for an isolated, universal input, power supply in the form of a single-ended resonant converter that utilizes capacitive energy storage versus magnetic energy storage, for converting an ac or DC input voltage to a variable voltage and current DC output or a variable ac output voltage, current, frequency, or phase. The preferred topology is a direct ac to ac, single-ended resonant converter using a single switch (4) and integrated magnetic element (1) with inherent near-unity power factor. Advantages of this method include a significant reduction in global energy consumption, simpler circuitry, substantially lower cost, higher efficiency, and longer operational life.

Abstract: The present invention is a circuit for regulating the current across an impedance load. This current regulating circuit is comprised of a main current path including a first control path, a reference-current path including a similar, second control path, and a control means including a pulse generator, a current source controller and an operational amplifier for controlling the first and second control paths in parallel.

Abstract: A current mode hysteresis controller for an inverter circuit provides selectable hysteresis bands based on the level of current to be provided. In the preferred embodiment of the controller, selected upper and lower limits are provided with hysteresis band switching being performed by selecting the amplification factor of error signals used to control the current mode hysteresis controller.

Abstract: A circuit arrangement for supplying a load (15) with energy from a power supply mains (1 to 5; 21, 22, 23) conveying at least one alternating voltage (UW; R, S, T) includes a simple network to ensure both a uniform energy supply of the load (15) and a reliable suppression of interference from the load to the power supply mains and in the reverse direction by means of a rectifier arrangement (7 to 10) which for each terminal (4, 5; 21, 22, 23), of the power supply mains includes a rectifier stage (7, 8; 9, 10; 24, 25; 26, 27; 28, 29) constituted as a first branch of a bridge rectifier. For each rectifier stage an energy storage device (11; 12; 30; 31; 32) can be charged by and is connected to said stage in accordance with a complementary branch of the bridge rectifier. For each stage a switching element (13; 14; 33; 34; 35) is provided for connecting each energy storage device to the load.

Abstract: This invention provides a means for suppressing radiated electromagnetic radiation in high current AC/DC power supplies. This radiation is the result of rectifier diode transient noise which is propagated through the electrical network of the power supply. The transient noise is propagated through the electrical and mechanical connections of the diodes to the transformer secondary. These connections have stray impedance which allows high frequency noise to be propagated through them. The stray impedances can be modulated to suppress the high frequency noise propagation without adding discrete inductor or capacitor elements to the electrical network. The modulation of the stray impedances is accomplished by adjusting the current sharing between rectifier diodes. This is accomplished by splitting the parallel connection between rectifier diodes, and making the connection of the diodes to the transformer secondary at various points along the secondary.

Abstract: Disclosed is an apparatus for storing electrical energy in a superconducting coil. The secondary phenomenon of magnetic induction which limits the size of existing superconducting energy storage coils is overcome by utilizing two superconductor material coils coupled by mutual induction through a high permeability magnetic material. This eliminates induction in the superconductor material thus eliminating the difficulty of the destruction of superconducting capability because of secondary induction. This construction permits high current storage capability in a small volume.

Abstract: There is disclosed a circuit for generating a reference voltage including first means for lowering the the input bias below an externally applied voltage and reducing first the variation of the voltage level due to the applied voltage, second means for causing the flow of a current depending on the output of said first means to sense the applied voltage state and generating the reference voltage increased by the amount of voltage dropped through the resistance produced according to said current flow to the output terminal of said reference voltage when a fixed constant voltage is applied, and third means for charging and discharging a part of the applied current according to the applied voltage variation of said second means.

Abstract: An uninterruptible power supply includes removable individual power modules, which for example may be 10 kilowatts each and are removable from the overall system without adversely affecting the remaining modules. Each module by means of pulse width modulated switching converts the line AC to DC where it is stored by use of capacitors or a battery and then inverted from DC back to AC. This is done on a three-phase basis without need of any low frequency transformer connection. Common input and output control units provide for the basic pulse width modulated switching signals and other necessary signals.The efficiency and speed of the system is enhanced by the use of cascode switches, saturable cores in transformers and inductors, and a proportional base drive to the switching transistors.

Abstract: An AC polyphase motor drive includes a current-controlled inverter comprising a plurality of semiconductor devices made up of power switches, such as IGBTs, and diodes. Current sensors integral with respective ones of a first group of the semiconductor devices sense the current delivered to each of the motor phase windings and a controller compares the sensed currents to a set of command signals to control operation of a second group of the semiconductor devices.

Abstract: A high voltage power supply current regulator includes at least one high voltage rectifier diode having a plurality of pn junctions, said diode being adapted to be connected between a high voltage power supply whose current is to be regulated and a load such that the diode is reverse biased. A control circuit, operating at a voltage which is relatively low compared with the power supply voltage, controls the reverse current through the diode to the load. The reverse current constitutes the load current. The control circuit includes a light source for illuminating the pn junctions of the diode with a predetermined flux of photons, the reverse current through the diode being a function of the photon flux on the diode junctions.

Abstract: A control circuit is provided for controlling the on-time of a pair of switching transistors in a half bridge converter. The control circuit includes a first comparator for comparing the converter output voltage with a reference voltage. The control circuit also includes a circuit which generates a first signal indicative of the current through the primary winding of the converter output transformer. Also included is a circuit which generates a second signal indicative of the on-time of one of the switching transistors exceeding the on-time of the other switching transistor. The first and second signals are averaged and compared with the output voltage of the first comparator by a second comparator. The second comparator controls the on-time of the switching transistors. In this way, any imbalance in the on-time of the switching transistors is corrected by the control circuit.

Abstract: A power supply for providing multiple operating potentials to a load switching controller is capable of providing constant voltage d.c. outputs from any of a plurality of a.c. voltage sources including the full range of power supply voltages and frequencies commonly used in various geographic locations throughout the world. The power switching element on-time is controlled by sensing the output voltage levels and providing feedback control of the switching element. A status circuit provides an indication of either an overvoltage of an undervoltage condition.