Abstract: A current control circuit (208) for a power converter (200) to control the switching thereof, wherein the current control circuit comprises a digital controller (210) using a logical input signal (226) to produce a logical control signal (212) with a fixed fundamental frequency for the power converter.

Abstract: An uninterruptible power supply (UPS) system (100) comprises a plurality of UPS units (UPS-1, UPS-2) connected in parallel. The controllers (130) of the units are programmed to implement a voltage calibration procedure and a current calibration procedure, in order that measurements of voltage and current made by sensors within the different units will agree. In the current calibration procedure, the load is disconnected (302) while one of the units is selected as a master and operates in a voltage control mode (VCM) (Steps 304-308). Each other unit is selected in turn and operated in a current control mode (310, 312). Current measurements made in the master unit are communicated (314) via a data bus to the selected unit and compared (316) with measurements made in the unit itself. The unit adapts its current sensing gains to match the master unit.

Abstract: Disclosed is a control circuit for control of a semiconductor switching device, such as an IGBT. The control circuit comprising a first feedback path between a first electrode and a control electrode of said semiconductor switching device which has a capacitance. The circuit is operable such that the capacitance in the first feedback path is dependent on the voltage level at said first electrode. In another embodiment the control circuit is operable such that a feedback signal begins to flow in the first feedback path immediately as the semiconductor switching device begins switching off, thereby causing a control action on the semiconductor switching device.

Abstract: The present disclosure relates to a controller, a circuit and method for controlling a power converter using pulse width modulation (PWM). At least one logic block (13, 15, 16) of the controller is configured to remove a command (4) which is configured to control the other power semiconductor switch (2) in a half-bridge (1,2) so that the other power semiconductor switch (2) remains in a non-conductive state while an antiparallel diode (6) allows an electric current (5) to pass in one direction, called the diode's forward direction, while blocking current in the opposite direction. In case the diode (6) is conducting instead of the other power semiconductor switch during the duration of the state of the command, the switching command (4) for the latter is omitted.

Abstract: Methods and apparatus are provided that can be used to control a set of power switches operating as a power converter.

Abstract: An uninterruptible power supply (UPS) system (100) comprises a plurality of UPS units (UPS-1, UPS-2) connected in parallel. Each UPS unit comprises a power converter (124) for supplying a share (i load 1, i_load—2) of a total load current (i_tot). The total load is shared automatically between UPS units of power ratings, in a proportionate manner. A controller 130 of each converter is arranged to establish real-time feedback control of a current supplied by the power converter. An exchange current (i_exch) for each converter represents an imbalance between an output current of the converter in question and output currents of the parallel converters. Exchange current sensing circuits of the parallel-connected UPS units are connected together. The controller steers the exchange current of each converter toward a value (i_exc_c) that is a non-zero proportion of a current (i_mut) sensed within the converter.

Abstract: A system for restricting mixing of air in a data center includes a plurality of racks, each of the racks having a front face and a back face. The system includes an enclosure for collecting air released from the back faces of the plurality of racks, the enclosure configured to substantially contain the air in an area between the first row and the second row and having a roof panel coupled to the first row of racks and the second row of racks configured to span a distance between the first row of racks and the second row of racks. The enclosure is configured to maintain a first air pressure inside of the enclosure that is substantially equal to a second air pressure outside the enclosure.

Abstract: A system and method for modeling airflow and temperature are disclosed.

Abstract: A system for regulating gas flow for a computer room containing computer components includes vents configured to direct gas from a gas supply toward the computer components, sensors disposed and configured to provide information regarding at least a first property associated with the computer components, and a controller coupled to the sensors and the vents and configured to effect a change in gas flow through a second one of the vents in accordance with a first value of the first property associated with a first of the computer components.

Abstract: A ventilation system for a fuel cell power module is provided. The ventilation system includes a ventilation enclosure for evacuating fluids from the fuel cell power module, the ventilation enclosure having an air inlet for providing ingress of air to the enclosure. The ventilation system further concludes a ventilation shaft in fluid communication with the ventilation enclosure and an evacuation pump arranged to exhaust fluid from the ventilation enclosure to a desired location.

Abstract: A power reduction aggregation system for controlling and measuring power usage at a plurality of individual user locations which includes a plurality of power reduction controllers and a power reduction module. Each power reduction controller is disposed at one of the plurality of individual user locations and includes a controller module and an energy consumption module. The controller module is configured to selectively control power to a plurality of loads associated with each of the individual user locations. The energy consumption module is coupled to the controller module and is configured to determine energy reduction indicia associated with at least one of the plurality of loads. The power reduction module is communicatively coupled to each of the plurality of power reduction controllers and is configured to determine an aggregate energy reduction estimate by combining the energy reduction indicia determined by the plurality of power reduction controllers.

Abstract: A front-end converter in an uninterruptible power supply system is described. In an exemplary design, a front-end converter includes a boost circuit having first and second inputs, positive, negative, and neutral output nodes, an inductor, AC inputs, a battery, and first and second devices. The boost circuit is configured to provide a positive capacitor voltage between the positive and neutral nodes and to provide a negative capacitor voltage between the negative and neutral nodes. The first device selectively couples the inductor to a first AC input or a positive port of the battery and the second device selectively couples a negative port of the battery to the second input. The inductor is coupled to the first input and is shared between an online mode of the converter and an on-battery mode of the converter. The battery is coupled through the inductor to the first input during the on-battery mode.

Abstract: In one aspect, the invention provides a system for power distribution. According to some embodiments, the system includes a rack mountable power distribution unit including a housing having a first end and a second end, the housing also including an outer wall defining a cavity within the housing, and fastening elements configured to allow the housing to be mounted within an electrical equipment rack. In accordance with these embodiments, the outer wall of the housing includes an opening extending linearly between the first end and the second end of the housing and a plurality of electrical conductors located within the cavity and oriented linearly between the first end and the second end. In accordance with further embodiments, the system includes a tap module.

Abstract: A power distribution unit disclosed herein includes a plurality of power outlets arranged in adjacent columns, the first and the second terminals of the power outlets in a first column formed along a first line, the first and the second terminals of the power outlets in a second column formed along a second line, ground terminals of the power outlets in the first column formed along a third line, and ground terminals of the power outlets of the second column formed along a fourth line, wherein the first line, the second line, the third line, and the fourth line are arranged in parallel, and wherein the plurality of power outlets are arranged in one of an arrangement in which the third and fourth lines are positioned between the first and second lines, and an arrangement in which the first and second lines are positioned between the third and fourth lines.

Abstract: A method and an apparatus for controlling distribution of power. The apparatus is used for controlling application of power to a plurality of devices including at least one master device and at least one controlled device. The apparatus includes: a power inlet constructed and arranged to receive power from a power source; a plurality of power outlets including at least one master power outlet (12M) and at least one controlled power outlet (12S); and means for generating a power profile of the at least one master device electrically connected to the master power outlet, determining a characteristic of a stand-by power consumption level of the at least one master device and controlling a supply of power from the power inlet to the at least one controlled power outlet in response to a comparison of a characteristic of power delivered to the at least one master device with the characteristic of the stand-by power consumption level.

Abstract: A system for restricting mixing of air in a data center includes a plurality of racks, each of the racks having a front face and a back face. The system includes an enclosure for collecting air released from the back faces of the plurality of racks, the enclosure configured to substantially contain the air in an area between the first row and the second row and having a roof panel coupled to the first row of racks and the second row of racks configured to span a distance between the first row of racks and the second row of racks. The enclosure is configured to maintain a first air pressure inside of the enclosure that is substantially equal to a second air pressure outside the enclosure.

Abstract: The invention is directed to a system for remote monitoring of a space and equipment. The space and equipment may, for example, be a sever room and associated network equipment. The system has network appliances, a server, and a client machine. The server receives data from a network appliance. The server may then deliver an application and data to the client machine for viewing and manipulating the data. The client machine may display the data as a mapping, displaying icons associated with the network appliances. The client machine may also graph the data. Further, the client machine may manipulate the organization of the data, the configuration settings of the network appliances, and store map and graph configurations.

Abstract: According to one aspect of the invention, a UPS includes an input configured to be coupled to an AC power source, a DC power source, an output configured to receive power from at least one of the AC power source and the DC power source, a first switched receptacle outlet coupled to the output and configured to be coupled to a first electrical load and a second receptacle outlet coupled to the output and configured to be coupled to a second electrical load. According to some embodiments, the UPS also includes a control unit configurable to provide a first configuration associated with the first switched receptacle outlet, where the first configuration is employed by the control unit to control a connection of the first switched receptacle outlet to the output independent of the second receptacle outlet.

Abstract: According to one aspect, embodiments of the invention provide a UPS comprising a plurality of electrical buses, a first AC/DC converter coupled to the electrical buses and configured to convert a first input AC voltage to a plurality of DC voltages, a second AC/DC converter coupled to the electrical buses and configured to convert a second input AC voltage to the plurality of DC voltages, a third AC/DC converter coupled to the electrical buses and configured to convert a third input AC voltage to the plurality of DC voltages, a first DC/AC converter configured to convert the plurality of DC voltages into a first output AC voltage, and a DC bus balancer configured to maintain voltages present on the electrical buses by transferring energy between the plurality of electrical buses.

Abstract: A system for cooling gas heated by passing the gas over heat-producing equipment to cool the equipment comprises a heat exchanger including a first heat transfer mechanism configured to transfer heat from the heated gas to a first coolant, and a first condensing module connected for fluid communication with the heat exchanger and including second and third heat transfer mechanisms, the first condensing module being configured to transfer heat through the second and third heat transfer mechanisms from the first coolant to second and third coolants in the second and third heat transfer mechanisms, respectively.