Quotables
"The production of too many useful things results in too many useless people."
Karl Marx
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 7269037 | Power supply with a direct converter A power supply includes a direct converter provided in the form of a two-phase or three-phase bridge circuit. The bridge branche of the direct converter includes a serial connection of any number of identical two-terminal networks, each having the following characte... | 09/11/2007 |
| 7239091 | Discharge lamp lighting apparatus for lighting multiple discharge lamps A discharge lamp lighting apparatus is provided for lighting a plurality of discharge lamps including one reference lamp and at least one controllable lamp. First variable inductance element and lamp current detecting unit are connected to the reference lamp, second... | 07/03/2007 |
| 7135653 | Multi-phase alternating current plasma generator A plasma generation system that is powered with an alternating current power source has been developed. The system includes a plasma generator that heats gas to a high temperature to form plasma. The gas is heated by passing through an electrical arc generated by el... | 11/14/2006 |
| 7116205 | Transformer and voltage supply circuit thereof for lighting tubes A transformer. The transformer drives a plurality of lighting tubes and comprises a coupling iron core, a first winding around the coupling iron core, a first bobbin disposed between the first winding and the coupling iron core, a plurality of second windings, indep... | 10/03/2006 |
| 7109667 | Discharge lamp driving apparatus A discharge lamp driving apparatus comprises a DC power supply, a control circuit, switching elements, a step-up transformer, and a lamp current controlling circuit. In the discharge lamp driving apparatus, the secondary side of the step-up transformer is connected ... | 09/19/2006 |
| 6930578 | Field adjustable phase shifting transformer A field-adjustable phase shifting transformer apparatus for canceling harmonic currents in a three-phase alternating current (AC) power distribution system includes a primary having a plurality of sets of contact points for receiving power from a three-phase AC powe... | 08/16/2005 |
| 6424552 | Multiphase transformer having main and auxiliary transformers A multi-phase transformer system is provided having a main transformer fed by an N-phase voltage and a separate auxiliary transformer fed by the N-phase voltage. Windings in the main transformer are connected to secondary windings in the auxiliary transfo... | 07/23/2002 |
| 6269009 | Compact polyphase electrical power converter having a single ferromagnetic core A polyphase generator for medical diathermy apparatus comprises a ferromagnetic ring core bearing two primary windings each of which has two winding portions positioned diametrically opposite one another. The winding portions in each case are connected in... | 07/31/2001 |
| 6169674 | Transformer, system and method to control harmonic distortion Harmonic distortion in a multiple phase power system is controlled by enabling different phase relationships to be set, and changed, in the field, between the devices being energized and the power source providing the energization. This has particular app... | 01/02/2001 |
| 5852553 | Harmonic neutralized voltage sourced inverter employing phase shifting interphase transformers Sets of phase shifting interphase transformers are used to combine the outputs of six-pulse static inverter stages to generate harmonic neutralized outputs with higher pulse counts. The phase shifting interphase transformers have a primary winding and at ... | 12/22/1998 |
| 5717586 | Single winding power converter The present invention provides smooth conversion of electric power between an AC line operating at a first voltage and a DC line operating at a second voltage bearing a fixed ratio to the first voltage. In one embodiment, polyphase AC is converted to ripp... | 02/10/1998 |
| 5666277 | Series-compensated converter station A series-compensated converter station in an installation for transmission of high-voltage direct current is connected to an alternating-voltage network (N) with three phases (A, B, C, respectively). The converter station comprises at least two direct-vol... | 09/09/1997 |
| 5541830 | Aerospace DC power supply having neutral point controller Dc aerospace power supplies include neutral point controllers to interconnect primary or secondary windings of the supplies into wye connected primary or secondary circuits. In power supplies having neutral point controllers in the primary circuits, the p... | 07/30/1996 |
| 5515264 | Optimized high power voltage sourced inverter system A voltage sourced inverter system includes an inverter for coupling to a DC power source and an interphase transformer bank coupled to the inverter. The inverter includes a number of poles for providing discretely displaced voltage waveforms to the interp... | 05/07/1996 |
| 5499176 | Pulse transformer circuit for isolating electrical signals A signal isolator circuit employing a pulse transformer overcomes the disadvantages of both prior art opto-coupler and pulse transformer signal isolator circuits by employing an active signal retrieval circuit which, in a higher accuracy configuration, re... | 03/12/1996 |
| 5455759 | Symmetrical, phase-shifting, fork transformer In 12-pulse and 18-pulse AC/DC converter systems a single wye connected auto transformer using appropriate segments of voltage from each phase connected in fork fashion is used to develop 6-phase and 9-phase voltages in a symmetrical manner such that inhe... | 10/03/1995 |
| 5434771 | Adaptive harmonic distortion control for parallel connected inverters A control for an inverter system having first and second inverters that produce inverter outputs wherein the inverter outputs are combined by an interphase transformer (IPT) to produce an AC output includes circuitry for detecting a magnitude of a harmoni... | 07/18/1995 |
| 5379207 | Controlled leakage field multi-interphase transformer employing C-shaped laminated magnetic core A multi-interphase transformer for use in power conditioners such as cycloconverters wherein polyphase input power sources with more than six phases and requiring interphase transformers for paralleling the polyphase outputs is disclosed, Such multi-inter... | 01/03/1995 |
| 5337227 | Harmonic neutralization of static inverters by successive stagger Quasi-harmonic neutralized inverter systems are provided with interphase transformers connected in a waffle tree configuration and each having a pair of inputs for receiving staggered voltage waveforms, wherein the stagger angle of the voltage waveforms r... | 08/09/1994 |
| 5148357 | Auto-connected hexagon transformer for a 12-pulse converter A 12-pulse converter of lower rating and minimal current harmonics is obtained with an auto-connected regular hexagon transformer including a delta winding in its center.... | 09/15/1992 |
| 5079499 | Transformer providing two multiple phase outputs out of phase with each other, and pumping system using the same A three-phase transformer includes six windings, disposed in three pairs, all of which six windings are serially interconnected. A desired turns ratio between the two windings of each pair establishes a desired phase shift between one three-phase output o... | 01/07/1992 |
| 5068774 | 24-pulse hexagon-type AC/DC static converter An AC/DC or DC/AC converter includes a single hexagon transformer with each side connected to opposite polarity DC terminals through two pairs of SCR devices gated in sequence synchronously with the frequency of the AC lines, gating in a pair lagging gati... | 11/26/1991 |
| 4933621 | Current chopping strategy for switched reluctance machines A method and apparatus are provided for controlling the switching devices in a switched reluctance machine bridge inverter having at least two switching devices per phase. One switching device is used for hysteresis band current chopping to regulate phase... | 06/12/1990 |
| 4912618 | Variable speed, constant frequency generating system with input transformer A variable speed, constant frequency generating system has a neutral forming autotransformer connected between a variable speed generator and an AC to AC converter. The converter includes a three-phase full wave-rectifier with positive and negative rails ... | 03/27/1990 |
| 4876634 | Multi-pulse converter system In a multiphase AC/DC converter system a single transformer is used having phase shifted tappings drawn from a polygonal succession of long and short windings wherein some of the windings carry only the difference between the outputted currents derived fr... | 10/24/1989 |
| 4833583 | Electric supply device for an ozonizer Device for supplying power from a three-phase network to an ozonizer comprising at least two discharge elements (3, 4) having a capacitive character, and comprising two single-phase step-up transformers (1, 2) having air gaps connected in a SCOTT circuit ... | 05/23/1989 |
| 4831352 | Rectifier transformer A rectifier transformer for supplying a predetermined alternating current to a rectifier includes: a transformer having secondary windings (cell windings) connected in a double star in such a manner that common terminal side conductors of the secondary wi... | 05/16/1989 |
| 4796173 | Low input voltage resonant power converter with high-voltage A.C. link A high-frequency resonant power converter transforms a relatively low D.C. input voltage to a relatively high A.C. link voltage to drive a resonant circuit. The high A.C. voltage appearing across a resonance circuit high-voltage capacitor is then transfor... | 01/03/1989 |
| 4758771 | Apparatus for driving AC motor This invention relates to an apparatus for driving an ac motor that includes a current controlled type power converter which produces an ac current or power having an arbitrary frequency at its output, a first switch provided to connect the power converte... | 07/19/1988 |
| 4698739 | 12-Pulse motor drive The present invention relates to an AC motor drive including two sets of inverters, wherein one transformer is converted on the output of one of the two inverters, the output of the transformer being connected in series with the output of the other invert... | 10/06/1987 |
| 4683527 | AC/DC or DC/AC converter system with outboard commutation inductors In a 12-pulse AC/DC converter of the hexagon type the rectifier switches are distributed in three groups for each polarity and for each polarity three coils are joined to the common pole and connected separately to the pairs of rectifier switches of a cor... | 07/28/1987 |
| 4680686 | Electric 3-phase supply device for an ozonizer A supply device connected to a 3-phase mains supply for an ozonizer comprising at least two capacitive discharge elements (7, 8). The device comprises two single-phase step-up voltage transformers (1, 2) having air gaps (5, 6) connected in a Scott circuit... | 07/14/1987 |
| 4625269 | High voltage D-C transmission power station with a generator transformer In the high voltage d-c transmission (HGU) power station in a block circuit, a three-phase generator feeds a 12-pulse high voltage d-c transmission (HGU) short coupler through at least one shifting transformer which serves for forming voltages of two thre... | 11/25/1986 |
| 4549258 | Inverter device using gate turn-off thyristors Herein disclosed is an inverter device which includes two or more groups of unit switching circuits connected in parallel with a d.c. power source and each having gate turn-off thyristors connected in series with each other. Further inclusive are current ... | 10/22/1985 |
| 4532581 | Circuit for reducing harmonics and pulsation in multiplex polyphase rectifying circuits or inverters, respectively provided with interphase reactors A circuit for reducing harmonics in the current on AC side and the pulsation in the voltage on DC side in a multiplex polyphase rectifying circuit or an inverter, each having an interphase reactor and plural rectifying circuits, wherein a plural number of... | 07/30/1985 |
| 4513240 | Method and apparatus for selective cancellation of subsynchronous resonance Apparatus and process for the selective cancellation of harmonic frequencies of current produced in a multiphase dynamic stabilizer. A plurality of multiphase dynamic stabilizers providing electrical stabilization are interconnected to a multiphase AC ele... | 04/23/1985 |
| 4498127 | Static converter with electric valves comprising a twelve-phase connection with two Graetz bridges for the suppression of harmonics 5 and 7 of network current There is disclosed an alternating current to direct current static converter which includes a three-phase transformer interconnected with two rectifier bridges to produce a twelve-phase connection for direct current output. The twelve-phase connection is ... | 02/05/1985 |
| 4488211 | Harmonic and pulsation reducing circuit used in a multiplex polyphase rectifier circuit A harmonic and pulsation reducing circuit used in multiplex polyphase rectifier circuits such as a multiplex polyphase rectifier, a branch reactor, an external commutated invertor, etc. which is characterized in that a rectifier circuit to rectify the ind... | 12/11/1984 |
| 4428150 | Electrode arrangement for electric weed killing apparatus Apparatus for destroying weeds in and around crop rows has a high voltage source of electricity mounted on a vehicle; a coulter wheel for connecting the high voltage source to the ground; a plurality of weed contacting electrodes carried on the vehicle an... | 01/31/1984 |
| 4366532 | AC/DC or DC/AC Converter system with improved AC-line harmonic reduction In a transformer-rectifier converter system, at least one inductance is inserted in the commutation path of two adjacent diode or thyristor devices in a cluster of three devices related to a common DC polarity pole, the reactance due to such inductance be... | 12/28/1982 |
