Abstract: A heat sink apparatus for drawing heat from one or more devices and a method of attaching such a heat sink to one or more devices is provided. The heat sink includes a mounting surface, which draws heat into the heat sink where it is dissipated by fins. The heat sink can be mounted next to the device to be cooled with minimum insertion force since the weight of the heat sink is borne by the printed circuit board upon which the electronic device is installed. A rotatable cam is turned by the user, which engages a pivot arm. The pivot arm rotates a number of spring clips against the device thereby holding it in place. Onceina fully closed position, the cam locks into place to prevent the pivot arm and spring clips from rotating back to an open position. The spring clips affix the heat sink and maintains contact between the mounting surface and the device being cooled.

Abstract: An uninterrupted power supply (UPS) device with uninterrupted neutral from input to output utilizes the same converter for converting rectified AC power and battery power to positive and negative high voltage (HV) rails. A simple circuit is utilized for connecting the battery to the conversion components of the PFC circuit without adverse affect on the performance of the PFC circuit, and while holding the battery substantially connected to neutral. In a first embodiment, the circuit comprises a simple combination of four diodes and a pair of high pass capacitors arranged so that in both power line and battery supply modes the battery is balanced around neutral. In a second, preferred embodiment, one terminal of the battery is connected directly to neutral.

Abstract: Presented is a modular uninterruptible power supply system utilizing common power modules, and providing redundant coordinated control thereof. The system and method of the instant invention provides identical control logic within each of the individual power modules, thus dispensing with the requirement for a separate control module to control and coordinate the operating modes and parameters of the UPS system. A system is presented whereby a virtual master is established through an arbitration scheme at initialization of the UPS system. The master then assigns a virtual vice master to provide the redundant back up control should the virtual master no longer be able to perform its functions. Nearly simultaneous control of operational mode and state change functions is accomplished through a coordinated communications system including a high-speed communications bus and digital control logic lines.

Abstract: A battery terminal jumper clip is presented that is capable of providing series battery connection between adjacent batteries in a battery stack useful for an uninterruptible power supply. The battery terminal jumper clip accommodates tab type terminal connectors and utilizes a single piece unitary construction. Once inserted to provide series coupling between adjacent batteries, the battery terminal jumper clip prevents inadvertent removal by providing a snap-on locking surface for the tab terminal connectors. Lateral removal is also inhibited via axial retention surfaces on either side of the battery terminal jumper clip. A bus surface provides a current path between adjacent tab connectors in the series coupling, and mechanical connection is insured through the provision of at least tab retention clip.

Abstract: Provided is a multi-function, single-piece handle and modular electronic component incorporating same, and a method of inserting and removing the handle from the modular electronic component. The unitary structure of the handle includes insertion and extraction claws that aid in the insertion and extraction of the modular component from a rack mount upon rotation of the handle to an upward, and vertically extended position respectively. The handle also includes a stowage locking mechanism that maintains the handle in a stowed position on the front of the modular component. A rack locking mechanism is also provided integral with the handle to secure the modular component in its rack mount position. Affirmative user actuation is then required to allow the modular component to be removed therefrom. Outrigging mounting and support legs are also included to add rigidity and strength to the handle to allow it to be used to carry the modular component.

Abstract: Systems, methods and computer program products are provided for displaying a graphical user interface (GUI) within a display device of a computer, wherein GUI functions are provided independently of the computer operating system. GUI controls are configured to inherit at least one style property, such as color, shape and typography, from the operating system in order to maintain the look and feel of the particular operating system. A first panel, having a display area configured to display information associated with an application program executing within the computer, is displayed within the operating system desktop (or browser window). A second panel is displayed within the desktop (or browser window) and is positioned beneath the first panel. The second panel is movably associated with the first panel between a hidden position beneath the first panel and an exposed position adjacent the first panel.

Abstract: A connectionless paralleling and load sharing system and method for power sources are presented. The invention provides a dynamic feedback adaptive control system that enables proper load sharing among paralleled power sources without the need for interconnection therebetween. Only the individual source's voltage and current are sensed by its controller. These output parameters are then used to modify a reference voltage used by the controller to control the source's output waveform. This reference voltage compensation is accomplished through two feedback control loops, an outer loop for the voltage compensation and an inner loop for the current compensation. The outer loop includes an integration of the voltage error between the desired voltage and the actual voltage sensed at the source's output. The inner loop is filtered and operates in a proportional fashion to rapidly adjust the output.

Abstract: An uninterruptable power supply system for producing an AC voltage from at least one of a DC power source or an AC power source includes an input terminal configured to receive an AC voltage from an AC power source, and an inverter operative to produce an AC voltage at an output thereof from a DC power source. A ferroresonant transformer circuit includes a transformer having an input winding, a output winding, and a third winding that forms part of a resonant circuit that produces saturation in the output winding when an AC voltage on the input winding exceeds a predetermined amplitude. A transformer input control circuit is coupled to the input terminal and to the inverter output and is operative to couple at least one of the input terminal and the inverter output to the input winding.

Abstract: A power transfer apparatus includes a first switch operative to couple and decouple a first AC power source to and from an AC power bus responsive to a first control signal and a second switch operative to couple and decouple a second AC power source to and from the AC power bus responsive to a second control signal. A first switch control circuit generates the first control signal responsive to a first AC source voltage produced by the first AC power source and to a first inhibit signal and generates a second inhibit signal responsive to a state of the first switch. A second switch control circuit generates the second control signal responsive to a second AC source voltage produced by the second AC power source and to the second inhibit signal and generates the first inhibit signal responsive to a state of the second switch.

Abstract: A power converter includes first and second voltage busses and a neutral bus. A first switching circuit, e.g., a rectifier circuit, is operative to selectively couple an input node thereof to the first and second voltage busses. A balancer circuit is operative to selectively couple the neutral bus to the first and second voltage busses such that relative magnitudes of respective first and second voltages on the first and second voltage busses are controlled responsive to respective first and second rates at which the balancer circuit couples the first and second voltage busses to the neutral bus. A second switching circuit, e.g., an inverter circuit, is operative to selectively couple the first and second voltage busses to a load connected at an output node thereof.

Abstract: An electrical cabinet or chassis for an uninterruptible power system (UPS system) includes universal bays or slots that can receive either power modules or battery backs. The back plane of the slot has separate connector terminals for battery packs and power modules. The slots may also receive battery chargers if so desired. All of the slots of a chassis can be utilized to full capacity before another cabinet needs to be employed. The cabinet is also readily adaptable and can be easily reconfigured as desired without particular concern as to the number of power modules or battery packs that are being used. Sensors are provided which indicate the capacity of the cabinet that has been used (e.g. the number of slots still open and not used by a power module or a battery pack).

Abstract: Twelve-pulse rectifiers include a first controller that controls a first six-pulse rectifier, a second controller that controls a second six-pulse rectifier and a data network that couples the first controller and the second controller to exchange data therebetween. The first and second controllers preferably have a common architecture and preferably operate independently. Each controller preferably controls its associated six-pulse rectifier as a function of the current and/or voltage output of the associated six-pulse rectifier, preferably using conventional feedback control techniques. Moreover, the first controller also preferably controls the first six-pulse rectifier as a function of a second current at the second six-pulse rectifier output, and the second controller preferably controls the second six-pulse rectifier as a function of a first current at the first six-pulse rectifier output.

Abstract: A heat sink apparatus for drawing heat from one or more devices and a method of attaching such a heat sink to one or more devices is provided. The heat sink includes a mounting surface, which draws heat into the heat sink where it is dissipated by fins. The heat sink can be mounted next to the device to be cooled with minimum insertion force since the weight of the heat sink is borne by the printed circuit board upon which the electronic device is installed. a rotatable cam is turned by the user, which engages a pivot arm. The pivot arm rotates a number of spring clips against the device thereby holding it in place. Once in a fully closed position, the cam locks into place to prevent the pivot arm and spring clips from rotating back to an open position. The spring clips affix the heat sink and maintains contact between the mounting surface and the device being cooled.

Abstract: A power supply apparatus includes an AC input port and a rectifier circuit, coupled to the AC input port, that produces a DC voltage at a rectifier circuit output from an AC input voltage at the AC input port. The apparatus further includes a selective harmonic current inducing circuit, coupled to the rectifier circuit output, that induces a harmonic component in a current delivered to a load from the rectifier circuit output. The selective harmonic current inducing circuit may control a phase and a magnitude of the induced harmonic current component in order to achieve selective suppression of a harmonic input current at the AC input port. The power supply apparatus may further include a filter circuit, coupled to the AC input port, that selectively suppresses a first harmonic current at the AC input port. The selective harmonic current inducing circuit may control the phase and magnitude of the induced harmonic current component such that a second harmonic current at the AC input port is suppressed.

Abstract: A power supply apparatus includes an AC input port, an output port, and a bypass circuit that couples the AC input port to the output port. An AC/DC converter circuit, e.g., a rectifier circuit, produces a DC voltage from an AC input voltage at the AC input port. A DC/AC converter circuit, e.g., a current mode controlled inverter, controls current transfer between the output port and the AC/DC converter circuit responsive to a control input such that respective first and second component currents of a current delivered to a load coupled to the output port pass via respective ones of the bypass circuit and the DC/AC converter circuit. The DC/AC converter circuit may be operated such that current passing through the bypass circuit is constrained to be substantially in phase with the AC input voltage.

Abstract: A modular uninterruptible power supply is presented having multiple power modules installed therein. Each of the individual power modules contains an internal bypass circuit sized for its particular power module. Preferably internal bypass circuitry is sized to carry two per unit load. The system and method of the invention also includes internal control circuitry for each of the modular power modules that control transitions between the inverter and bypass modes of operation. This transition control is coordinated with the other controllers for the other modular power modules installed in the uninterruptible power supply. Both the high speed communication bus and a high level interrupt line are utilized to minimize the transfer break time between different modes of operation while ensuring that the inverter is never paralleled with the utility line voltage. To further minimize this transfer time, a solid state switching circuit is utilized to provide the initialization between operational modes.

Abstract: Presented is a center switching circuit and an inverter and an uninterruptible power supply (UPS) utilizing same. The center switching circuit selectively enables and disables power flow to and from the bus capacitors of an inverter or UPS. As such, the center switching circuitry effectively removes the bus capacitors from the circuit. This allows operation of the inverter or UPS in a high efficiency mode whereby input line voltage may be passed essentially without compensation to the output when the center switching circuit is open. Modulation of the center switching circuit during this mode provides soft charging of the bus capacitors so that they are available to source current in a double-conversion or DC boost mode upon degradation or loss of the line voltage. To supply output power from the bus capacitors, the center switching circuit is closed to associate these capacitors with the neutral.

Abstract: An uninterrupted power supply (UPS) device with uninterrupted neutral from input to output utilizes the same converter for converting rectified AC power and battery power to positive and negative high voltage (HV) rails. A simple circuit is utilized for connecting the battery to the conversion components of the PFC circuit without adverse affect on the performance of the PFC circuit, and while holding the battery substantially connected to neutral. In a first embodiment, the circuit comprises a simple combination of four diodes and a pair of high pass capacitors arranged so that in both power line and battery supply modes the battery is balanced around neutral. In a second, preferred embodiment, one terminal of the battery is connected directly to neutral.

Abstract: A heat sink apparatus for drawing heat from one or more devices and a method of attaching such a heat sink to one or more devices is provided. The heat sink includes a mounting surface, which draws heat into the heat sink where it is dissipated by fins. The heat sink can be mounted next to the device to be cooled with minimum insertion force since the weight of the heat sink is borne by the printed circuit board upon which the electronic device is installed. A rotatable cam is turned by the user, which engages a pivot arm. The pivot arm rotates a number of spring clips against the device thereby holding it in place. Once in a fully closed position, the cam locks into place to prevent the pivot arm and spring clips from rotating back to an open position. The spring clips affix the heat sink and maintains contact between the mounting surface and the device being cooled.

Abstract: A line-interactive single conversion uninterruptible power supply (UPS) utilizing a multiple tapped ferroresonant transformer and a square wave PWM inverter is presented. During normal utility line operation, the line voltage is not modified in any way, except for ferroresonant filtering and regulation. Tap control circuitry insures proper tap selection based on the utility input voltage. During tap transitions in utility out of specification operation, a second power source, such as an inverter, is operated to provide output power to the connected loads. The control of the inverter switching angles may be accomplished through a look-up table. This look-up table contains the converter pulse widths for monitored battery voltage. No output voltage feedback is required. Based on the inherent regulation provided by the ferroresonant transformer, the PWM control may be accomplished in course steps.