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| Number | Title | Issue Date |
| 7898104 | Apparatus and method for dynamically balancing loading of a polyphase circuit A controller box comprises an array of switches for arbitrarily connecting loads to any selected power phase of a polyphase supply circuit. By evenly balancing the loads amongst the phases the efficiency of the total power delivered is thereby improved. ... | 03/01/2011 |
| 7732940 | Apparatus and method for reducing neutral line current using load switching method An apparatus for reducing a neutral current using a load switching method in accordance with the present invention includes a phase current detection unit for detecting a phase current in each of a top stage power line and a bottom stage power line, a load switching... | 06/08/2010 |
| 7692329 | Current sharing for multiphase power conversion Current sharing scheme based on input power and/or the power efficiency for a power stage with multiple phases and/or paralleled modules is described. According to the scheme, duty cycles of different phases/modules may be adaptively adjusted until the minimum input... | 04/06/2010 |
| 7646109 | System for distributing AC power within an equipment rack A system comprises a first equipment rack, a power distribution unit (PDU) and a plurality of rack connectors. The PDU is mounted in the first equipment rack and is configured to provide alternating current (AC) power that comprises a plurality of phases. The plural... | 01/12/2010 |
| 7425778 | Apparatus and method for compensating secondary currents used in differential protection to correct for a phase shift introduced between high voltage and low voltage transformer windings Provided is an apparatus and method for providing to a differential relay an operational vector-group compensation setting pair that automatically provides correction for a phase shift occurring between currents of at least two windings of a power transformer. The m... | 09/16/2008 |
| 7368830 | Polyphase power distribution and monitoring apparatus A polyphase power distribution and monitoring apparatus having sets of outputs for each phase of power and monitors for each phase of power disposed in the housing. Each monitor provides a visible display of current for an associated phase of power and an audible al... | 05/06/2008 |
| 7259477 | Uninterruptible power supply An uninterruptible power supply (UPS) system includes an AC power input configured to receive AC power from a single-phase AC power source or a multi-phase AC power source, a DC power source, an output circuit including a power output, a controllable switch configur... | 08/21/2007 |
| 7242110 | Control system for canceling load unbalance of three-phase circuit A control system for canceling load unbalance of a three-phase circuit includes phase current detectors for detecting phase currents caused to flow through a secondary circuit of a current transformer provided in high voltage distribution lines, respectively, phase ... | 07/10/2007 |
| 7230216 | Induction heating method and unit It is an object of the present invention to prevent temperature decrease in a border portion of each of heating coils and to enable to eliminate an influence given by the change in a load state. In order to attain this object, an induction heating unit according to ... | 06/12/2007 |
| 7196900 | Adaptable rack mountable power distribution apparatus Embodiments of a power distribution apparatus that is adaptable to be readily mounted within a variety of differing types of electronic equipment racks are herein described. One such embodiment provides power distribution apparatus having an upper mounting adapter. ... | 03/27/2007 |
| 7141891 | Intelligent power distribution system An intelligent power distribution system including one or more intelligent power strips. The power strips can each include an elongated housing that may be adapted for mounting in an equipment rack. The housing can include a first end, a second end and plurality of ... | 11/28/2006 |
| 6628009 | Load balanced polyphase power distributing system The invention is an apparatus and a method for connecting loads to a polyphase power distribution system in such a way that the loads on the individual phases of the system are balanced. The apparatus includes an equipment rack having multiple electrical ... | 09/30/2003 |
| 5142468 | Power conditioning system for use with two PWM inverters and at least one other load A coupling circuit (30) connects two three-phase pulse width modulated (PWM) inverter circuits (16, 18), used in conventional manner to power a first load (12), in order to independently power a second load (32). In a preferred embodiment, the two PWM inv... | 08/25/1992 |
| 4893069 | Ferroresonant three-phase constant AC voltage transformer arrangement with compensation for unbalanced loads A ferroresonant three-phase constant AC voltage transformer comprising three transformer iron cores with one for each corresponding input supply phase, primary windings and secondary windings formed on each of the transformer iron cores, series reactance ... | 01/09/1990 |
| 4868481 | Apparatus and method for balancing electrical currents in a multiple-phase system A current balancer for balancing one or more currents provided from a three-phase source to a load includes three current transformer/full-wave rectifier bridge sections and one or more saturable core reactors. Each of the current transformer/full-wave re... | 09/19/1989 |
| 4792703 | Earthed circuit for an electric railway car An earthed circuit for an electric railway car which is equipped with an electric circuit including an electrical apparatus for which a switching operation is performed by use of a power semiconductor device includes a first brush attached to one of the a... | 12/20/1988 |
| 4743864 | Power saving intermittently operated phase locked loop In an intermittently operative phase-locked loop, in order to prevent the oscillator frequency from significantly changing at the time of turning on of an electric power source, a point in time at which a phase difference between clock signals respectivel... | 05/10/1988 |
| 4574231 | Magnetic amplifier apparatus for balancing or limiting voltages or currents An apparatus for controlling electrical characteristics in an alternating current system includes a first level of magnetic amplifiers which are responsive to a primary direct current control signal. The magnetic amplifiers provide secondary control signa... | 03/04/1986 |
| 4352026 | Multi-phase current balancing compensator An apparatus which automatically balances the magnitudes of each phase current in a multi-phase power system includes electrical conductors, or phase lines, variable reactance evices, and control elements. Each phase line connects to a variable reactance ... | 09/28/1982 |
