Abstract: A system including a transceiver that is in a first device and receives wirelessly or over a powerline and from a second device, (i) a voltage value of a voltage detected between bus bars of a power source, where the power source supplies power to a load, and where the load is distinct from the first and second devices, or (ii) a current value of a current detected by a current sensor and drawn from the power source by the load. A sensing module one of (i) if the transceiver receives the current, detects the voltage and timestamps the voltage value with a first timestamp, and (ii) if the transceiver receives the voltage, determines the current and timestamps the current value with a second timestamp. A parameter module determines a parameter of the load based on the voltage, the current, and the first and second timestamps.

Abstract: A system is disclosed for detecting if a remote device is associated with a power supply. The system may have a controller having machine readable, non-transitory executable code running thereon for varying a characteristic of a signal being applied to the power supply. The controller further may be configured to compare a measurement obtained from a measurement subsystem relating to a measured signal present at the remote device. The controller may also be configured to make a comparison between the signal being applied to the power supply and the measured signal obtained at the remote device, and to determine whether the remote device is electrically associated with the power supply.

Abstract: The disclosure provides systems and methods for regulating and distributing cooling fluid through a plurality of heat sinks, such as cold plates, using a flow regulator, which sets the total flow rate, in combination with one or more individual orifices that allow further flow distribution as required by individual cold plates, despite flow variations upstream of the orifices. An orifice can be coupled to an orifice holder, which includes a body to support the orifice, and which may be coupled (directly or indirectly) to an inlet of the cold plate. Alternative manners of coupling orifices in the fluid flow besides an orifice holder can be employed. Generally, the flow regulator(s) is coupled with a plurality of orifices and conduits through which the cooling fluid flows. Related system components can be assembled as a module for installation into a cooling system that includes other system components such as a pump, compressor or other pressure sources for the cooling fluid.

Abstract: An uninterruptible power supply (UPS) system has an inverter having an output coupled to a primary side of an output transformer. The UPS system has a controller having a dual gain voltage regulator for controlling the output voltage of the inverter of a UPS system that uses active and reactive current components of a load current flowing out an output of the UPS system.

Abstract: A cooling system for a data center in which equipment racks are disposed has a cooling unit and a controller coupled to the cooling unit. The cooling system includes temperature sensors at or near the cooling unit's air return inlet, at or near the cooling unit's air supply outlet, and at or near the equipment racks air inlet(s). The controller measures these temperatures. A relative humidity sensor is located at or near the air return inlet of the cooling unit. The relative humidity where the relative humidity sensor is located is measured by the controller using the relative humidity sensor. The controller calculates the dew point temperature from the temperature sensor and relative humidity. Using this dew point, which is essentially constant throughout the space being conditioned, and the temperatures from the other locations, the controller then calculates the relative humidity at each location.

Abstract: A multiple UPS system includes a plurality of multi-module UPS subsystems coupled to a power tie cabinet, each multi-module UPS subsystem having a plurality of UPS modules. The power tie cabinet includes one or more controllers, collectively referred to as PTC (power tie cabinet) controls. The PTC controls periodically determine a power error message for each of the multi-module UPS subsystems and pass it to the respective multi-module UPS subsystem. A controller of the multi-module UPS subsystem uses the power error message to determine error data that is provided to a power average control loop used in control of power sharing among the UPS modules of the multi-module UPS subsystem.

Abstract: A valve assembly comprising an inlet port, an outlet port, and a diaphragm configured to selectively allow communication between the inlet port and the outlet port, the diaphragm including a first side adjacent the ports and a second side opposed to the ports. The valve preferably includes at least one bleed path between the first side and the second side of the diaphragm with a one way flow device configured to allow flow from the first side to the second side of the diaphragm and prevent flow from the second side to the first side of the diaphragm. The valve may include a first bleed path from the inlet port to the second side of the diaphragm and a second bleed path from the outlet port to the second side of the diaphragm. Either bleed path, or both, may comprise a check valve mounted in the diaphragm.

Abstract: A heat exchanger can have a manifold which includes a plurality of laminated sheets that allow a customization of the heat exchanger. The design can allow for a more optimal flow of coolant to areas of high load, thereby making the temperature distribution across the heat exchanger more uniform, or intentionally non-uniform. Furthermore, the laminated sheets can allow multiple circuits to be employed in the heat exchanger such that different coolants can be utilized therein and maintained separate from one another. The tubes can be microchannel tubes. A single set of manifolds can be used with multiple heat exchanger cores to provide a more compact heat exchanger. Mounting features can be integral with a group of the sheets.

Abstract: When the preferred voltage source for a static transfer switch is a UPS, there can be a brief interruption in the voltage received from the UPS while the UPS is switching from economy mode to normal mode. Operation of the static transfer switch can be improved during such voltage disturbances. Specifically, the static transfer switch may be in data communication with the UPS and thereby made aware that the voltage disturbance is temporary. As a result, the static transfer switch can avoid an unnecessary transfer to an alternate voltage source.

Abstract: A method is provided for operating a static transfer switch to eliminate transformer inrush current in the presence of residual flux. The method includes: detecting an interrupt of electric power at an output terminal of the static transfer switch; controlling amplitude of voltage at the output terminal using phase fired control of one or more silicon controlled rectifiers interposed between a voltage source and the output terminal, where the amplitude of voltage is set at a value less than a peak value of the sinusoidal waveform; and increasing the amplitude of voltage at the output terminal incrementally until the amplitude reaches a peak value.

Abstract: A control method is disclosed that involves controlling zero-crossing operation of bridge arms in a UPS, wherein the UPS has a rectifying bridge with first and second switching transistors, a midline bridge arm with third and fourth switching transitors, and an inverter bridge arm with fifth and sixth switching transitors. The midline and rectifying bridge arms are controlled to cross zero synchronously. The inverter bridge arm is controlled to be disconnected during a period before a zero-crossing point of the rectifying bridge arm to a period after the zero-crossing point of the rectifying bridge arm. The periods before and after the zero-crossing point of the rectifying bridge arm are time differences between the zero-crossing points of the inverter bridge arm and the rectifying bridge arm. The influence of asynchronous zero-crossing between the PFC circuit and the inverter circuit on the UPS performance indices may be reduced by using the present control method.

Abstract: The present invention discloses a control method for a soft switch circuit in a switch power source, which generates an alternating primary power filter current by controlling first and second primary power switching devices to be closed and opened, and generates an intermittent alternating resonant current in the same direction as the primary power filter current in a resonant branch by controlling forward and backward auxiliary switching devices to be closed and opened to thereby achieve closing of the first and second primary power switching devices at a zero voltage, and which generates a balance current with the same magnitude as and in the opposite direction to the resonant current in the resonant branch in at least a period of time during the resting of the resonant current by further controlling the forward and backward auxiliary switching devices to be closed and opened to thereby achieve an average current of zero across the resonant branch in a switching cycle.

Abstract: A repetitive controller, a control method thereof and a feedback control system are disclosed. The repetitive controller includes an internal model section, a periodic delay module and a compensation module. An input quantity is input into the repetitive controller via an input terminal of the internal model section; the internal model section, the periodic delay module and the compensation module are connected in series. The repetitive controller further includes a particular frequency selection and passing module, connected in series with the internal model section, the periodic delay module and the compensation module or configured on a forward path of the internal model section. In the repetitive controller of the disclosure, a particular frequency selection and passing module is incorporated such that only the harmonic at the selected frequency are filtered out, thereby realizing the function of removing the harmonic at the particular frequency.

Abstract: This invention relates to a T-type three-level inverter circuit. The circuit includes an absorption unit.

Abstract: A pumped refrigerant cooling system having multiple pumping units for providing working fluid to a load to enable cooling of a space via the load. The pumped refrigerant cooling system operates the pumping units at less than capacity. When a pumping unit is deactivated, the output of the remaining pumping units is increased to maintain fluid flow.

Abstract: A system is disclosed for monitoring an electrolyte level in a battery cell and generating an indication of a fault condition when the electrolyte level drops below a predetermined acceptable level. The system may make use of a controller, an ultrasonic transmit circuit for transmitting an ultrasonic signal into an interior area of the battery cell, and an ultrasonic receive circuit for receiving the ultrasonic signal after it has been reflected from the interior area of the battery cell. The controller may use the reflected ultrasonic signal and a predetermined calibration signal representing the predetermined acceptable level of the electrolyte to determine when the electrolyte level has dropped below the predetermined acceptable level.

Abstract: A climate control system or a data center includes a computer room air conditioner (CRAC) and an air economizer. A control module determines whether outside air is suitable for use in cooling the data. If the outside air is suitable for use, outside air and not the CRAC is used to cool the data center when the dry bulb temperature of the outside air is below a minimum set point. The outside air is conditioned before it is introduced as supply air so that it is above a minimum temperature. If the outside air is suitable for use and the dry bulb temperature of the outside air is above the set point, the control module determines a cooling percentage of cooling of the data center to be provided by the CRAC and a cooling percentage to be provided by the outside air.

Abstract: A system and method of isolating an uninterruptible power supply system is disclosed that comprises bypassing an inverter section of the power supply to couple primary power to a load bus; and, thereafter, isolating the power supply by simultaneously uncoupling the power supply from the load bus and coupling the primary power to the load bus.

Abstract: A multiple UPS system has a plurality of UPS subsystems with a separate UPS data communications bus coupling a controller of each UPS subsystem to an associated controller of an associated tie cabinet. The multiple UPS system further includes a data communications tie bus that couples the controllers of the tie cabinets to each other. The controllers of the tie cabinets arbitrate power line based coordinating signals between the UPS buses without the use of auxiliary signals.

Abstract: A cooling system is provided that comprises: a refrigerant loop having a pump; an evaporator heat exchanger thermally coupled to a heat source, the evaporator plumbed in the loop; a condensing heat exchanger and a receiver plumbed in the loop; and an equalizing conduit plumbed between an inlet to the condenser and the receiver and comprising a flow regulating valve.