in

Ring binder mechanism

A ring binder mechanism includes an elongate plate having a longitudinal axis. Hinge plates are supported by the plate for pivoting relative to the elongate plate. Ring members are mounted on the hinge plates and moveable between a closed position and an open position. A control structure is supported by the elongate plate and controllably pivots the hinge plates to move the ring members between the closed and open positions. The control structure has a travel bar connected to the hinge plates for moving the hinge plates between the closed and open positions. A spring biases the travel bar toward the closed position.




in

Ring binder cover

A cover (10) is disclosed for holding objects such as papers and reports. The cover (10) is formed of a member (12) having a front cover (14), a spine (16) and a back cover (18), a ring binder (22) and a paper surround (24). The paper surround (24) encapsulates the ring binder (22) and secures it to the member (12). The cover can be either a top bound or side bound cover.




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Sheet holder and edge pattern making apparatus incorporating the same

A sheet holder for holding a sheet of paper and exposing an edge of the sheet, has a press for holding the paper sheet and exposing the edge, and a lever for operating the press. The lever is movable between a released position for placing of the edge of the paper sheet in the press and a holding position for operating the press. There is also an abutment for abutment by the edge of the paper sheet to position the edge relative to the press while the lever is in the released position. The abutment is associated with the lever for moving away from the edge of the paper sheet when the lever moves towards the holding position, thereby exposing the edge of the paper sheet.




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Binding assembly

A binder assembly for receiving and retaining articles and that includes a cover having a spine portion and at least one cover leaf portion and a first binder element and a second binder element having a plurality of first and second retaining fingers, respectively. The first and second binding elements are moveable between 1) an open position wherein articles are permitted to be removed from or mounted to the binder assembly, and 2) a closed position wherein articles mounted to the binder assembly are prevented from being removed. The binder assembly further includes an elongated retainer/lock constructed to releasably attach to the first and second binding elements in the closed position thereof with the spine portion of the cover therebetween for locking the first and second binding elements in the closed position and securing the first and second binding elements to the spine portion of the cover.




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Ring binder mechanism

A ring binder mechanism has an elongate housing, a pair of locking elements, a translation bar, a pair of elongate hinge plates having mating ring halves extending there-from, a plurality of mating ring halves, and an actuator. Movement of the actuator moves the hinge plates, translation bar, and locking elements to cause the ring halves to disengage so a user can place holed paper over the open ring halves, or closes the ring halves together to secure the paper with the closed-loop rings thus form while simultaneously locking the rings in the closed-loop configuration to prevent inadvertent opening.




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Binder apparatus

Binder apparatus are described. An example binder apparatus includes a housing, a first support rail positioned within the housing and a second support rail positioned within the housing. The binder apparatus also includes first and second closure members coupled to the respective support rails. The closure members are positioned on the respective support rails to enable locking elements of the closure members to interlock when the binder apparatus is in a closed position. The binder apparatus also includes a lever comprising tabs that are received by recesses defined by the support rails. An interaction between the tabs and the support rails enables the support rails to be moved relative to one another and the locking elements to be moved to an unlocked position.




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Self-supporting book

A book has a front cover having a first edge which is unconnected, and an opposing second edge which is connected to a spine. A back cover has a first edge which is connected to the spine and an opposing second edge which is connected to flexible joint or fold-line. The book has a third cover having a first edge which is connected to flexible joint and an opposing second edge which is connected to binding which contains pages and a stabilizing sheet.




in

File binder and document organizer

Disclosed herein is an organizer comprising a unique structural configuration to house and store both non-perforated documents and perforated documents. The organizer comprises a ring binder that is associated with an expandable compartment that is arranged peripheral to the ring binder.




in

Binding device

A binding device includes binding rod portions, coupling portions for coupling a plurality of the binding rod portions, and an axis portion serving as a center upon opening/closing of binding rods. The coupling portions have lower portions to which the axis portion is provided at a position close to base portions of the binding rods so that a leaf bound at the binding rod portions can be flipped along the binding rods and flipped through 360 degrees and leaves can make contact with each other with the axis portion sandwiched therebetween. The axis portion includes a shaft portion and receiving portions for the shaft portion. The receiving portions are provided to the coupling portions the shaft portion is disposed therein.




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Binder apparatus

Binder apparatus are described. An example binder apparatus includes a housing and a first carrier rail having a first longitudinal edge and a second longitudinal edge. The first carrier rail defining a notch adjacent the second longitudinal edge. The housing biasing the first carrier rail by engaging the first longitudinal edge. The binder apparatus includes a second carrier rail having a third longitudinal edge and a fourth longitudinal edge. The housing biasing the second carrier rail by engaging the third longitudinal edge. The second longitudinal edge hingably engaging the fourth longitudinal edge, the notch defining an opening having a first edge and a second edge opposite the first edge. The binder includes a slider having a control element extending therefrom. The control element comprising a first control surface and a second control surface. The first control surface to engage the first edge to urge the first and second carrier rails to an open position, the second control surface to engage the second edge to urge the first and second carrier rails to a closed position.




in

Binder clip

Placing sheets around a retainer or between a retainer and clamp and securing a clamp against the sheets and retainer for compressively fixing the pages against the retainer.




in

Binding device

A binding device includes a plurality of binding rings, a holding member which enables the binding rings to be disposed with a spacing therebetween, an operating member having a surface to which base portions of the binding rings are secured such that the binding rings are disposed with a spacing therebetween, the operating member including a pair of operating pieces movable in the holding member in a longitudinal direction of the holding member, and an opening-closing member which causes the binding rings to be changed in an opening direction. The opening-closing member includes an elastic member. The elastic member is provided in the operating member such that a distance between the operating pieces in an opening-closing direction of the binding rings is maintained at a distance enabling the pair of the operating pieces to be moved and is arranged to move the pair of the operating pieces defining the operating member relative to each other in respective opposite directions and so as to elastically urge the pair of the operating pieces in a direction allowing the binding rings to be held in an opened state.




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Ring binder

A ring binder, with a fixed bar (1), bearing hooks (2) and a moving bar (3), wherein the fixed bar (1) is immovably fixed on a spine plate of a folder; the bearing hooks (2) are fixed on the upper surface of the fixed bar (1); the moving bar (3) is movably lapped over one side of the fixed bar (1); the lower surface of the moving bar (3) and the lower surface of the fixed bar (1) are clamped and connected with each other; the moving bar (3) can rotate relative to the fixed bar (1) and slide along the length direction of the fixed bar (1); a spring (4) connected between the moving bar (3) and the fixed bar (1); and moving shackles (5) fixed on the upper surface of the moving bar (3). As the ring binder lacks a base plate, a housing, etc., both the opening and the closing of the binder are convenient and the cost of the ring binder is reduced.




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Binder

A binder includes a back part disposed between ring parts, each of the ring parts being openable and closable. to constitute a binder. A penetration hole is formed at a portion of the ring parts intersecting with the back part, thereby allowing the binder to expand and contract to a certain degree in a longitudinal direction thereof.




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Soft close ring binder mechanism with mating ring tips

A ring binder mechanism for retaining loose-leaf pages securely holds closed ring members together to prevent inadvertent loss of pages retained by the mechanism. The mechanism comprises a housing supporting two hinge plates for pivoting motion to open and close paired ring members mounted on the plates. Free ends of the paired ring members have interlocking configurations that securely join together when the ring members close. The configurations prevent misalignment of the closed ring members in all directions transverse to longitudinal centerlines of the ring members. The mechanism also includes locking elements that interact with the hinge plates to block their pivoting motion when the ring members are closed. This holds the free ends of the closed paired ring members together so that the interlocking configurations of the ring members remain interengaged.




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Page alignment device for scrapbooking

A scrapbooking page alignment device for temporarily aligning at least two adjacent scrapbook pages having retention receivers extending from their respective spine edges, the device comprising (i) a base; and (ii) two or more spaced retention posts extending from said base; where said retention posts are dimensioned to temporarily receive the retention receivers of the two adjacent scrapbook pages.




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Binder clip

A binder clip having flexible sidewalls biased to close around a rigid retainer for securing pages wrapped around the retainer or pinched by the binder clip and retainer for manually forming a book.




in

Recyclable ring binder apparatus with quick release ring metals

A recyclable ring binder apparatus comprises a ring metal incorporating a set of binder rings that are formed of a pair of ring halves. The ring metal can be firmly fastened to a spine section of a binder hardcover by utilizing a post and a small arched snap clamp with a tap. The tap of the snap clamp can be pressed around a neck of the post utilizing a quick release clipping mechanism. The snap clamp can be accessed with an index finger and slid away from the post to remove the ring metal from the hardcover. The ring metal, the hardcover, the snap clamp and the post can be quickly separated into their perspective categories due to the clipping mechanism. Hence, it retains conformance of all components of the ring binder apparatus for recycling without increasing development and production cost.




in

File binder and document organizer

Disclosed herein is an organizer comprising a unique structural configuration to house and store both non-perforated documents and perforated documents. The organizer comprises a ring binder that is associated with an expandable compartment that is arranged peripheral to the ring binder.




in

Binding device

A binding device is provided which allows reduction in profile. A binding device 10 includes: a holding member 16 having a length which allows a plurality of openable-closable binding rings 12 and 14 to be disposed with a spacing therebetween; an operating member 18 secured inside the holding member 16; and an opening/closing member 40. The operating member 18 includes a pair of operating pieces 30 and 32 on which the binding rings 12 and 14 are secured. For housing the opening/closing member 40, an opening/closing member housing portion 36 is provided in a manner such as to be recessed from a reverse side, opposite to a surface on which the binding rings 12 and 14 are secured, towards the surface side. The opening/closing member 40 is secured to the opening/closing member housing portion 36 of the operating member 18 on the reverse side opposite to the surface on which the binding rings 12 and 14 are secured, and is formed to, when the binding rings 12 and 14 are opened, cause the binding rings 12 and 14 to be changed in an opening direction so that the operating pieces are moved in a longitudinal direction of the holding member 16 and are held in a direction approaching an inner surface of the holding member 16, within the holding member 16.




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Binder with removable portfolio

The present invention is directed to an item holding assembly that may include a binder and portfolio with one releasably attached to the other enabling quick and easy separation for use of one independent of the other. In a preferred embodiment, binder and portfolio panels can overlie one another, particularly when releasably engaged in a manner that releasably attaches them. A flap, such as part of the panel or the panel of one is received in a pocket formed in the panel of the other to facilitate and preferably provide releasable attachment.




in

Unitary biochip providing sample-in to results-out processing and methods of manufacture

A biochip for the integration of all steps in a complex process from the insertion of a sample to the generation of a result, performed without operator intervention includes microfluidic and macrofluidic features that are acted on by instrument subsystems in a series of scripted processing steps. Methods for fabricating these complex biochips of high feature density by injection molding are also provided.




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Ring binder with interchangeable binder covers

A ring binder has a standard ring assembly having a ring base and upstanding rings, a ring assembly support having a plurality of indents positioned along its sides, a binder connector having a plurality of upstanding tabs, and a plurality of binder covers each having a center spine with a plurality of slots configured to accept each of the plurality of binder connector tabs. The ring binder is assembled by the insertion of the binder connector tabs into slots of the binder cover and then into the indents of the ring assembly support. The ring binder can be sold assembled or as a kit, which would include a plurality of interchangeable binder covers.




in

Ring binder mechanism

A ring binder mechanism includes a housing, a ring support, and rings for holding loose-leaf pages. Each ring includes a first ring member and a second ring member that are moveable between a closed position and an opened position. An actuator is mounted on the housing for moving the ring members from the closed position to the opened position. A travel bar has at least one locking element and is moveable between a locked position wherein the ring members are locked in the closed position and an unlocked position wherein the ring members are capable of being moved to the opened position. An intermediate connector operably connects the travel bar to the actuator. A portion of the intermediate connector is captured by and moveable with a wide section of a mounting groove in the travel bar so the intermediate connector can move relative to the travel bar.




in

Lever for a ring binder mechanism

A ring mechanism for retaining loose-leaf pages includes a housing and ring members for holding loose-leaf pages that are moveable relative to the housing between an open and closed position. An actuation system moves the ring members and includes hinge plates pivotally mounted on the housing and an actuator actuating pivoting movement of the hinge plates. A travel bar of the actuation system is moveable by the actuator between a locked position blocking pivoting movement of the hinge plates and an unlocked position allowing pivoting movement of the hinge plates. The actuation system is adapted to deform while moving the travel bar from the locked position toward the unlocked position to delay the pivoting motion of the hinge plates from the movement of the actuator.




in

Desktop loose-leaf base, and binder

A desk leaf base has a base formed of a trapezoidal tubular body in a trapezoidal shape in a side view, closed from a bottom surface to a certain height in both sides, and opened in an upper portion therefrom. An inclined front wall of the tubular body is removed from one side to the other side, in a range from the height to a higher height lower than a top surface. A binder mounted along an elongated top surface of the base has an elongated body and rings. The elongated body is mounted along the top surface of the base with an approximately same width as the top surface. The rings are mounted on the body and capable of opening and closing. Each ring includes linear portions that protrude from the body inclining upward on front and back sides when closing.




in

Ring binder mechanism having snap-in ring members

A ring mechanism has an elongate body made of a moldable polymeric material and rings for holding loose-leaf pages. Each ring includes a first ring member and a second ring member. The first ring members are movable relative to the housing and the second ring members between a closed position and an open position. At least one ring member for each ring is a separately formed ring member and comprises a ring portion and an anchor connected to the ring portion. The at least one separately formed ring member is formed separately from the body. The anchor of the separately formed ring member is secured to the body for pivoting movement relative to the body. The anchor can be received in a receptacle in the body adapted to receive the anchor.




in

Ring binder mechanism having unitary structure

A ring binder has an elongate body and rings. Each ring includes ring members moveable between open and closed positions. The ring members and body can suitably formed together as one piece from a moldable polymeric material. The binder suitably includes a retaining system operable to selectively and releasably hold the ring members in the closed position. When the ring members are in their open position, loose-leaf pages can be added or removed from the rings. Loose-leaf pages can also be moved from one ring member to another when the ring members are in their open position.




in

Ring binder mechanism having retaining system on ring members

A ring binder has an elongate body and rings. Each ring includes ring members moveable between open and closed positions. The body and rings are made of one or more moldable polymeric materials. The binder suitably includes a retaining system operable to hold the ring members in the closed position. The retaining system has interlocking formations adjacent ends of the ring members that are moveable between a retaining position in which the retaining system holds the first and second ring members in the closed position and a non-retaining position. The ring members and body can suitably be formed together as one piece from a moldable polymeric material.




in

Ring binder mechanism with self-locking actuator

A ring binder mechanism for holding loose-leaf pages has a housing having a cavity formed in the underside of a central portion of the housing. A pair of hinge plates are disposed between the sides for pivoting movement relative to the housing to open and close rings of the mechanism. The mechanism has an actuator moveable relative to the housing for opening and closing the rings. The actuator has a body, an opening arm extending from the body, a closing arm extending from the body, and a locking finger extending from the body. The closing arm extending into a space between the hinge plates and the central portion of the housing. The hinge plates extend between the opening and closing arms. The locking finger extends into the cavity in the central portion of the housing when the actuator is in the closed position.




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Contact organizing system and method

A contact organizing system has a ring device and a hole punching device. The ring device is shaped for holding the business cards. The hole punching device for adapted punching holes in the business cards. The hole punching device includes a hanging aperture through the hole punching device for hanging the hole punching device on the ring device.




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Document reading apparatus and document reading method

Provided is a document reading apparatus capable of suppressing a shock that may occur when a trailing edge of a tabbed sheet passes through a roller pair. In an image reading section, when a document to be read is the tabbed sheet, a timing to start separation of the roller pair in response to detection of a trailing edge of the document is delayed by a time period corresponding to a tab length with respect to the timing to start separation when a document other than the tabbed sheet is conveyed. Thus, it is possible to prevent the shock when the trailing edge of the tabbed sheet passes through the roller pair, and to thereby suppress image reading failure due to the shock.




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Actuating lever for a binder mechanism

An actuating lever for a binding mechanism includes a body formed of a first molded material. The body defines oppositely-facing surfaces, with at least one of the surfaces having a recess formed therein. The actuating lever further includes a grip member formed of a second molded material that is different from the first molded material. The grip member is molded at least partially into the recess.




in

Ring binder mechanism having dual time buffer actuator

A ring mechanism has an elongate housing and rings for holding loose-leaf pages. Each ring has ring members mounted on pivoting hinge plates for movement between open and closed positions. An actuator has opening and closing arms extending from an actuator body for opening and closing the rings. The mechanism has a travel bar moveable between a locked position in which a locking element blocks pivoting movement of the hinge plates and an unlocked position. The actuator has a flexible arm positioned to push the travel bar toward the locked position when the actuator closes the rings. At least a portion of the flexible arm is adapted to deform during closing in a manner that includes rotation in a first direction relative to the body of the actuator. Movement of the actuator to close the rings includes rotation of the actuator in the first direction relative to the housing.




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Controller that determines average output current of a switching circuit

A switching circuit (400) comprising an inductive component (406) including at least one winding; and a switch (404) is configured to transfer power from a voltage source (402) to the inductive component (406) in accordance with a switch control signal (412). The switching circuit (400) also comprises a controller (408) configured to integrate the voltage across the inductive component (406) in order to generate a signal representative of magnetic flux in the inductive component (406); and use the signal representative of the magnetic flux in the inductive component to account for a peak magnetization current value in order to control the switch (404).




in

Switched-mode compound power converter with main and supplemental regulators

In certain embodiments, the present invention provides a compound power converter in which the majority of power passes from input to output through only a single stage of power conversion. At least one embodiment includes a main converter with an auxiliary output. The auxiliary output energizes a reservoir that provides input power for a supplemental converter capable supplying the main output. The supplemental converter improves regulation and can provide holdover power for Power Factor Correction (PFC) or Uninterruptible Power Supply (UPS) operation.




in

Multi-level inverter control method and controller for a wind generation power system

A system, method, and apparatus for providing three level inverter modulation is disclosed. In one embodiment, control signals can be provided to control a three level inverter in a power converter based on at least one feedback signal.




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Additional electric power receiving method and device replacing conventional grounding with negative voltage source

An additional electric power receiving method replacing conventional grounding with a negative voltage source includes the step of transmitting electromagnetic wave or current from a power supply source to a rectifier, wherein a grounding end of the rectifier is in electrical communication with the negative voltage source, and the negative voltage source is selected from a negative potential intrinsic of an organism. A device applicable to the electric power receiving method includes a rectifier having an input end and two output ends, wherein the input end is in electrical communication with a power supply source, and rectified direct current is transmitted from the output ends. With the method and device, not only an increase in additional electric power obtained is achieved, but conversion efficiency and stability of current and electromagnetic wave is enhanced.




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Power converter having semiconductor switching element

Provided is a configuration in which it is possible to mount an applied voltage suppression circuit configured to prevent voltage breakdown of a semiconductor switching element, and a set voltage thereof can be inspected without damaging an IC or the like of a peripheral circuit. In a power converter having a semiconductor switching element, an applied voltage suppression circuit configured to suppress a voltage applied to the semiconductor switching element and at least one component of constituent components of a driving circuit which causes the semiconductor switching element to be turned off if the component is absent are transferred to and disposed on a slave substrate (separate unit) which is divided from and electrically connected to a master substrate including the semiconductor switching element, the driving circuit, a control circuit, and the like mounted thereon.




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Power supply, power management device applied to a power supply, and method for performing brown-out protection and overheat protection of a power management device

A power supply can provide brown-out protection and overheat protection. The power supply includes a rectifier, a transformer, and a power management device. The rectifier is used for receiving an alternating current voltage. The alternating current voltage has a voltage cycle. The transformer coupled to the rectifier has an inductor coupled to a switch for supplying an output voltage. The power management device is used for controlling the switch to make the inductor save power or release power. The power management device has a multi-functional pin coupled to the rectifier for receiving a detection voltage corresponding to a positive half cycle of the alternating current voltage. The multi-functional pin is also coupled to a thermistor for receiving an overheat protection signal.




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Alternating-current/direct-current converter

An alternating-current/direct-current converter includes a rectifier, a reactor, a capacitor, and a switching rectifier. The rectifier is configured to rectify alternating-current voltage output from an alternating-current power source, thereby converting the alternating-current voltage into direct-current voltage, and to output the direct-current voltage. The capacitor includes terminals. The switching rectifier is coupled to the AC power source and switchable to output the direct-current voltage to the capacitor.




in

Power converter and method for balancing voltages across input capacitors

A power converter and a method for balancing voltages across input capacitors are disclosed in the present application. The power converter includes: two DC input terminals; a first input capacitor and a second input capacitor; a first bridge arm and a second bridge arm connected in series with one another; and an output circuit configured to generate a signal required by the power converter based on the signals at a midpoint of the first bridge arm and a midpoint of the second bridge arm. The power converter further includes: a first voltage balancing unit and a second balancing unit configured to reduce a voltage difference between the first input capacitor and the second input capacitor. The power converter provided by the present application solves the problem of imbalance in the voltages across the first input voltage and the second input voltage.




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Circuits and methods for determining peak current

Embodiments include circuits and methods to determine peak current for current regulation. A control signal circuit monitors a current on the primary side of a transformer based a turn on time of a switch coupled to the primary side. The control signal circuit determines whether the monitored current exceeds an over-current protection threshold, and determines a duration that the monitored current exceeds the over-current protection threshold. The control signal circuit determines a peak primary current in the primary side based on the over-current protection threshold, the duration that the monitored current exceeds the over-current protection threshold, and the turn on time of the switch. The control signal circuit controls the turn on time for the switch based on the determined peak primary current.




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Switching power converting apparatus, switching controller for the same, and method of controlling a bipolar junction transistor of the same

A switching power converting apparatus includes a coil unit, a bipolar junction transistor (BJT) controlling power transfer through the coil unit, and a current sensing resistor sensing a current flowing through the BJT so as to produce a sensed voltage thereacross. A switching controller includes a current source supplying a first current, a current generating module generating, based on an input voltage associated with the sensed voltage, a second current, which is proportional to the current flowing through the BJT, a multiplexing module selecting one of the first and second currents as an output current, and a driving module outputting, based on the output current, a driving current, which is proportional to the output current, to the BJT to thereby conduct the BJT.




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Switching power supply

A flyback type switching power supply includes between P and N of a direct current output a sudden load change detector circuit, which normally has no power consumption, that detects only a transient fluctuation of a direct current output voltage, and starts the switching of a primary side semiconductor switch when there is no load or a light load, even when the semiconductor switch is in an off state, thereby enabling the detection of the direct current output voltage in a tertiary winding, and suppressing a drop in the direct current output voltage.




in

Power conversion system and drive chain comprising the power conversion system

Provided is a power conversion system that includes a first transformer adapted to be connected to an AC network, the first transformer including a first primary winding and two first secondary windings, and two power converters, each being connected to a first respective secondary winding. The system further includes a second transformer and a secondary electrical device, the second transformer including a second primary winding and two second secondary windings, each second secondary winding being connected to a respective first secondary winding, and the secondary device being connected to the second primary winding.




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Power-packet-switching converter with sequenced connection to link inductor

Methods and systems for managing link voltages in a power converter, where single phase, three phase or universal systems can be used. Common mode management refers to shifting of voltages in a particular direction to perform transition between input and output ports, in addition to maintaining soft switching property. Voltages in power converters can be freely increasing and decreasing, and thus damage to the circuit can be caused if these voltages change are not controlled.




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Printed circuit board

A power source circuit includes a switching circuit 4 that converts a direct current voltage obtained by converting an alternating voltage from an alternating power source input through a pair of power supply lines 2 and 3 into a predetermined direct current voltage by a switching operation. A fuse 5 is provided on one power supply line 2. A series circuit 9 including a first line bypass capacitor 7 and a resistor element 8 is connected between one power supply line 2 and a ground 6. A second line bypass capacitor 10 is connected between the other power supply line 3 and the ground 6. Imbalance of the circuit by an excess current protection element is prevented to reduce common mode noise.




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Grid-connected inverter and method for filtering AC output thereof

Disclosed is a grid-connected inverter and a method for filtering AC output thereof. The grid-connected inverter includes an AC output filter which includes two or more switchable filtering modules, with the power capacity of each filtering module corresponding to a different output power of the grid-connected inverter; a monitoring module which is used to perform realtime monitoring on voltage and current outputted by the grid-connected inverter; and a control circuit which is used to calculate an output power grade of the grid-connected inverter according to the voltage and the current monitored by the monitoring module and control switching to the filtering module having a corresponding power capacity according to the power grade, the power grade being selected from a plurality of power grades which are divided according to power capacities of the filtering modules.




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Even-level inverter

There is provided an even-level inverter, including: a voltage-dividing circuit dividing input DC power into an even number of voltage levels; a plurality of switching devices connected to individual nodes of the voltage-dividing circuit having the even number of voltage levels; and a bidirectional switching device connected to the individual nodes of the voltage-dividing circuit through at least one of the plurality of switching devices and including at least two transistors. According to the present invention, the bidirectional switching device is implemented without a diode to thereby reduce conduction loss caused due to an anti-parallel diode included in the related art bidirectional switching device, and a neutral point of the voltage-dividing circuit is electrically separated from the switching devices to thereby control reactive power.