D.c. Transformation, Inc.

Other

Avco Everett Research Laboratory, Inc.

Varentec, Inc.

United States of America As Represented by the Secretary of the Air Force

Auco Research Laboratory, Inc.

Rudolf Limpaecher

Alex Wilhelm Limpaecher

Erik R Limpaecher

In a general aspect, a charge transfer includes a transformer including a plurality of primary windings and a plurality of galvanically isolated secondary windings, a first plurality of resonant converters having input terminals connected in series to an input power terminal and having output terminals connected to different primary windings of the plurality of primary windings, a second plurality of resonant converters having input terminals connected to different secondary windings of the plurality of secondary windings and having output terminals connected to a galvanically isolated power terminal, and a control system for controlling a transfer of electric charge between the input power terminal and the galvanically isolated output power terminal including controlling a first plurality of switches of the first plurality of resonant converters and a second plurality of switches of the second plurality of resonant converters in a zero current soft switching mode.

Soft-switching high voltage power converter

In general, in one aspect, the invention relates to a method for delivering a controlled voltage. The method involves, during a first electric pulse delivered to a primary transformer, holding a first switching section open to isolate the controlled voltage, where the first electric pulse creates a first magnetic flux in a core of the primary transformer, and where the first magnetic flux generates a direct current (DC) magnetizing current. The method further involves receiving the controlled voltage from a voltage source using the DC magnetizing current at a first switching section, and upon termination of the first electric pulse, closing the first switching section to deliver the controlled voltage to the primary transformer.

Method and system for delivering a controlled voltage

An apparatus and method therefore transfers electric charge between a charge storage device (25) and a first power terminal (11) having a plurality of first-nodes. The method interchanges charge between the charge storage device and a first first-node of the plurality of first-nodes through an inductive section (22); and, when a predetermined charge has been interchanged between the charge storage device and the first first-node, replacing the first first-node by a second first-node of the plurality of first-nodes. Charge is interchanged between the charge storage device and the second first-node through the inductive section. Preferably, the ratio of the charge interchanged between the charge storage device and the first first-node and the charge interchanged between the charge storage device and the second first-node is equal to a ratio of the currents drawn from the first first-node and the second first-node. Charge can also be interchanged between the charge storage device and a second power terminal (12) using a similar method.

Charge transfer apparatus and method therefore

Method and apparatus for rectification derectification and power flow

A method of transferring energy from a power source into an output node including the steps of separately charging each of a plurality of energy storage elements from the power source; after the plurality of energy storage elements are charged, discharging a selected one of the energy storage elements through an inductive element into the output node; and as the selected energy storage element is being discharged through the inductive element, when its voltage reaches a preselected value, discharging another one of the energy storage elements through the inductive element into the output node.

Sequential discharge and its use for rectification

An electrical power transfer apparatus for connecting to a multiphase power line carrying a AC signal having a period of T.sub.AC, the apparatus including: a capacitive storage circuit; a plurality of charge transfer circuits connected to the capacitive storage circuit and each of which is connected to a different phase of the multiphase power line, wherein during operation the charge transfer circuits resonantly transfer power to and from the multiphase power line and capacitive storage circuit, wherein the resonant transfers to and from the capacitive charge storage circuit occur with a resonant frequency at least as great as 1/T.sub.AC ; and a control circuit coupled to the plurality of charge transfer circuits and which during operation causes the plurality of charge transfer circuits to transfer power between different phases of the multiphase power line via the capacitive storage circuit.

Compact and efficient power transfer system and method

A novel power conversion system includes an energy storage circuit including a plurality of capacitors forming multiple stages, wherein each of the multiple stages includes one or more of the capacitors; a charging circuit connected to the energy storage circuit and during a charging cycle charging the plurality of capacitors from a voltage source to a predetermined voltage; a circuit for inverting the polarity of the voltage across selected capacitors; and a discharging circuit connected to the energy storage circuit and during a discharging cycle extracting power from the plurality of connected capacitors at a transformed voltage. The energy storage circuit further includes an interstage coupling circuit that provides interconnections interconnecting the capacitor stages. During the charging cycle, the interstage coupling circuit assumes one of two modes and during the discharging cycle, it assumes the other of the two modes. In the first mode, the interconnections have low impedance and in the second mode, the interconnections have high impedance.

Compact and efficient transformerless power conversion system

A transformerless power conversion system including a plurality of capacitors connected in series; a charging circuit connected to the plurality of capacitors, the charging circuit charging the plurality of capacitors from a voltage source to a predetermined voltage; a circuit for inverting the polarity of the charge stored in selected capacitors of the plurality of capacitors, the polarity inverting circuit including a plurality of inductor circuits, each of which can be switchably coupled to a corresponding different one of the selected capacitors to form a resonant circuit which aids in inverting the polarity of a stored charge in that capacitor; and a discharging circuit for extracting power from the plurality of capacitors at a transformed voltage.

Disclosed is a new Transformerless Power Conversion System (TPCS) that allows a direct voltage step-up or step-down of DC or AC power without the use of magnetic core transformers. The operation is accomplished with solid state switching devices, capacitors, preferentially air core inductors and a switch control system. The conversion and step-up from AC to DC and the inverse process can be implemented with high efficiency and without the generation of harmonics. The transformer elimination in conjunction with high inversion frequency operation results in a low weight system without transformer core losses and third harmonic generation. For high ratio DC to DC transformation the TPCS transports the input charge directly to the output without requiring an AC link. The three distinct operations of charging, transformation, and energy discharge are typically in sequential order and allows a complete isolation between the input and output power grids. The TPCS allows complete power flow control and with it allows an improvement of power grid stability. A number of integrated TPCS modules can be configured to perform in a single system as a voltage transformation stage, a power converter or inverter, an output regulator, an AC phase angle corrector as well as a fast power interruption device. The architecture is specifically suited for high voltage DC power distribution systems with AC to DC conversion and step-up at the power station for HVDC transmission; DC to DC step down for DC distribution in place of AC; and final DC to polyphase AC power conversion near the bulk power consumers.

A spark gap switch is disclosed with a pumping system which utilizes flowing gas to replenish the interelectrode region between conductive pulses. The spark gap switch typically consists of a housing enclosing a gas filled chamber in which there are two end electrodes with an intervening trigger plane electrode that may be inserted at other than midplane. To initiate switch closure, a trigger pulse is applied between one end electrode and a trigger plane electrode causing the gas in the intervening gap to ionize and conduct and thereby bring on complete switch closure. To achieve proper gas flow each end electrode is configured as a truncated cone and gas is caused to flow from a multiplicity of ports spaced equidistantly around each cone base. The gas ascends the conical outer surface of each end electrode, sweeps over the crown and exhausts out through an opening in the center of each electrode. From a small plenum in the base of each end electrode some of the gas is exhausted out of the system while the larger fraction is recirculated. Recirculation is accomplished by jet pumps using pressurized fresh gas streaming from nozzles within the base plate structure of each end electrode to draw exhaust gas into mixing chambers. The resulting mixture of new and exhaust gas flows out of the multiplicity of ports spaced equidistantly around the base of each end electrode. The flow rate is controlled so that the flush factors are the same on each end electrode.

Spark gap switch with jet pump driven gas flow

A flowing gas laser utilizes a multilayer gas flow technique wherein laser gas is caused to flow in three distinct layers: an anode gas flow layer flowing adjacent the anode electrode of the laser; a cathode gas flow layer flowing adjacent the cathode electrode of the laser; and a lasing gas flow layer flowing between the anode and cathode layers and through the lasing region of the laser. A higher electron density is produced in the anode and cathode layers than in the middle lasing layer for fostering a higher electric field in the lasing layer and increased electrical efficiency of the laser. The multilayer gas flow technique is also useful in chemical processing devices for generating ozone or the like.

E-Beam maintained plasma discharge elecrodes

A fluidic amplifier or switch for supplying pulses of a power gas to be controlled which is insensitive to load impedance or back pressure. One arm of the fluidic switch comprising part of the gas injection path is coupled to a working outlet and the other arm is coupled through a sonic orifice to a vent outlet. An orifice is provided in the downstream end of the power gas injection path, the injection pressure is maintained at preferably at least about twice the maximum back pressure and a substitute gas is injected into the arm of the fluidic switch not carrying the power gas to be controlled. The two gases are each alternately supplied to the working outlet and the vent outlet. When the power gas to be controlled is supplied to the working outlet, the substitute gas is supplied to the vent outlet and when the substitute gas is supplied to the working outlet, the power gas to be controlled is supplied to the vent outlet to maintain the pressure constant across the working outlet orifice.

Fluidic switch

A high repetition rate high power spark gap switch of the type useful in pulsed lasers, radar systems and pulse-forming networks is enabled to operate with higher switching speed at high power levels by rapid chemical composition change cyclically made in the spark gap at high frequency with differing standoff voltage capabilities of different compositions produced in the gap in each cycle. The different standoff voltage capabilities are produced by injecting different gases under fluidic switching control.

Spark gap control

It has been discovered that plasma containment by a chamber having multi-pole magnetic cusp reflecting walls in combination with electronic injection for electrostatic containment provides the means for generating magnetic field free quiescent plasmas for practical application in ion-pumps, electronic switches, and the like. 1250 'Alnico V' magnets 1/2'.times.1/2'.times.11/2' provide containment in one embodiment. Electromagnets embodying toroidal funneling extend the principle to fusion apparatus.

Growing community of inventors

Topsfield, MA, United States of America

Rudolf Limpaecher