Abstract: A string combiner is provided for coupling multiple strings of series-connected photovoltaic (PV) panels in a PV array to downstream equipment, each string including positive and negative conductors. The combiner includes a combiner box containing a busbar connected to the protection devices for receiving and combining the currents from the multiple strings of PV panels, output terminals for connection to the downstream equipment, and a disconnect device within the combiner box and including a multi-pole switch connected to the busbar for disconnecting the downstream equipment from the multiple strings. A plurality of connectors are provided for connecting selected poles of the multi-pole switch to each other or to selected ones of the output terminals in either a grounded or an ungrounded configuration.

Abstract: Disclosed herein are a method of controlling the operation of battery modules in a battery system, which includes two or more battery modules or battery module assemblies, wherein the battery system further includes energy consuming loads for consuming charged energy, and the method includes, when a specific battery module or a specific battery module assembly is abnormally operated, connecting the abnormally operated battery module or the abnormally operated battery module assembly to the corresponding energy consuming load to forcibly discharge the charged energy, and a battery system that is capable of performing the battery system control method.

Abstract: When charge power or discharge power of each individual sodium-sulfur battery included in a plurality of sodium-sulfur batteries becomes 1/n (n is a natural number) or less of a rated output, individual sodium-sulfur batteries are sequentially stopped. This prevents the discharge power (or the charge power) of the sodium-sulfur battery from becoming minute, so that a battery depth (or a stored energy) of the sodium-sulfur battery can be accurately managed.

Abstract: A power supply includes multiple power cells and a master control system in communication with each of the power cells. The master controller includes a control processor configured to receive power cell control information and a host in communication with the control processor wherein the host is configured to receive command and status information.

Abstract: A method for wear leveling in an information handling system including multiple power supply units (PSUs) is provided. The method includes maintaining each PSU in one of multiple different operational states, collecting data relating to the use of each PSU, storing the collected data, and automatically changing the operational state of at least one of the PSUs based at least on the collected data regarding the use of each PSU in order to level the wear on the PSUs.

Abstract: The invention relates to a network with a number of terminals connected by lines. Data and a supply voltage for power supply of the terminals may be transmitted via said lines. At least one switching control unit and at least one switch device with a switch means are provided therefor. The switch means of the switch device may be activated or deactivated by means of operating the switch control unit. With activated switch means a terminal allocated to the switch device is switched on by being connected to a network voltage. With deactivated switch means a terminal allocated to the switch device is switched off by being disconnected from the network voltage.

Abstract: Disclosed herein are systems and methods for converting data samples representing alternating electric currents. The data samples may be obtained by sampling a first alternating electric current having a first frequency at a sampling frequency, sampling a second alternating electric current having a second frequency at the sampling frequency, and converting the data samples using a conversion algorithm to compensate for any discrepancy caused by the difference between the first frequency and the second frequency. The corrected data samples may be utilized to determine various characteristics of the alternating electric current, such as voltage magnitude, voltage phase angle, current magnitude, current phase angle, and other related attributes. In one application, the systems and methods disclosed herein may be utilized in connection with an intelligent electronic device used to couple a first electrical system, such as a power generator, to a second electrical system, such as a utility intertie.

Abstract: An apparatus for a photovoltaic system in which multiple poles are connectable with multiple fuses is provided. The apparatus includes a rotor configured to occupy at least first and second rotational angles, a disconnect unit including a plurality of interrupter housings respectively configured to connect at least one of the multiple poles with at least one of the multiple fuses in accordance with a rotational angle of the rotor, at least one of the plurality of the interrupter housings being mutually connectable, a transmission unit disposed and configured to electrically combine the multiple poles into a lesser number of the multiple poles, a housing sized to house the rotor, the disconnect unit and the transmission unit and an actuator arm disposed at the exterior of the housing and configured to be selectively actuated to cause the rotor to occupy the at least one of the rotational angles.

Abstract: An electrical switch apparatus for use in connecting and disconnecting a DC power source and a load includes first and second pairs of controllable electromechanical contacts coupled to the DC power source and the load for connecting the power source to the load when the contacts are closed, and disconnecting the power source from the load when the contacts are open. A controller is coupled to the electromechanical contacts and programmed to produce control signals for opening and closing the contacts. A diode is coupled to the electromechanical contacts to prevent electrical current from flowing from the load to the power source, and a controllable semiconductor switch is coupled to the controller and across the power source for momentarily short circuiting the source in response to a control signal indicating a transition of either or both of the first and second pairs of electromechanical contacts from a closed condition to an open condition.

Abstract: In one embodiment, each of a plurality of sites may produce surplus power. All or a fraction of the surplus power may be supplied to the power grid according to an agreement between the user of a site and an electric utility. A computer of the utility is in communication with a computer at each of a plurality of sites having a local power source. Terms of power provision that include an amount of power to be provided during a specified time of day is communicated between a site and the utility.

Abstract: A method and systems of adaptation of an active power supply set using an event trigger are disclosed. In an embodiment, a method includes providing power to a system load using an active power supply set. The active power supply set includes a power supply in an active mode. The method also includes detecting an event trigger. In addition, the method includes increasing a power mode of an additional power supply when the event trigger is detected. The method may include detecting an additional event trigger and decreasing the power mode of a unit of the active power supply set when the additional event trigger is detected.

Abstract: A photovoltaic system may include a DC to AC inverter, a voltage sensor configured to measure an input voltage from a photovoltaic array, and a controller configured to calculate a voltage differential.

Abstract: A method for providing power to devices in a network and coordinating actions of multiple power supplies on the network is described. The method may include maintaining connectivity of communication signals and ground between upstream and downstream portions of the network relative to a power supply, while terminating power from an upstream power supply and taking over power supply functions for downstream devices. This may be achieved by including a logic feature within one or more of the multiple power supplies that monitors a power status of an upstream power supply and/or the power status of the associated power supply. When the logic feature detects a power cycle, it initiates a coordinated power cycle of the associated power supply and/or other networked power supplies.

Abstract: A photovoltaic system includes: a photovoltaic generator comprising strings that each includes one or more photovoltaic cells; a power converter; switches; and a controller. The power converter is configured to convert direct current (DC) power provided by the photovoltaic generator into alternating current (AC) power, and to output the AC power. Each switch is associated with one of the strings and is configured to connect the associated string to the power converter when set to a first setting, such that power generated by the first string can flow to the power converter. Each switch is also configured to disconnect the string from the power converter when set to a second setting. The controller is configured to control the power provided by the photovoltaic generator by selectively connecting the strings of the photovoltaic generator to the power converter by controlling the settings of the switches.

Abstract: The invention relates to a redundant module for decoupling short-circuit currents in a redundant voltage supply. The redundant module comprises at least two power supply units, and the number of inputs corresponds at least to the number of power supply units. Each input is routed via a separate current path to a common current node of an output for providing an output current. Each current path forms a decoupling section, and at least one measuring element for measuring the input voltage, the input current, and/or the input power as well as a control element for regulation purposes are assigned to each decoupling section.

Abstract: The present invention proposes a method and a system for generating a bidirectional power flow between a DC component and an AC grid for a distributed power generation system using solar panels. The system includes an inverter that further includes a DC component for generating DC power and a single-stage DC-AC converter for converting the DC power into AC power by operating in one or more pre-defined modes. The AC power includes a reactive power component and an active power component.

Abstract: Systems, apparatuses, and methods for managing battery circuits in systems such as wireless communications service base stations are disclosed. An example apparatus includes a battery circuit having multiple strings of one or more serially connected batteries. The apparatus may be configured to rotate between battery strings such that one or more strings are maintained at or near an upper threshold while other string(s) are disconnected from the maintained string(s). The apparatus may also be configured to charge the battery circuit, to test the battery circuit, and to handle power failures.

Abstract: A power integrated circuit includes, in part, a multitude of controllers, a multitude of pulse-width generators, a multitude of output stages and a configuration matrix. Each controller is adapted to be responsive to a feedback signal and a reference signal to generate a control signal carrying pulse width information. Each control signal causes a difference between an associated output voltage feedback signal and the reference signal to be less than a predefined value. Each pulse-width generator is associated with and responsive to a different one of the controllers to generate a pulse-width modulated signal in response. The configuration matrix selectively couples the plurality of pulse-width generators to the output stages.

Abstract: A wind farm in which electrical power produced in the wind farm is transported via a wind-farm-internal network to a substation. Upon being transferred to an external network, the electrical power is transformed to a voltage which is higher by a selectable step-up ratio than the voltage in the wind-farm-internal network. The electrical load level on a wind energy installation in the wind farm is determined, and the step-up ratio is adjusted as a function of the electrical load level. Accordingly, it is possible to influence the voltage in the wind-farm-internal network such that the wind energy installations are subject to a lower electrical load level.

Abstract: DC-DC converters are described that employ a time-averaged modulated bypass diode to facilitate the efficient harvest of power in photovoltaic systems.

Abstract: For connecting a PV array via an inverter to an AC power grid, at first a DC link at the input side of the inverter is pre-charged from the AC power grid. A link voltage of the DC link is adjusted to a pre-set value with the inverter connected to the AC power grid, the pre-set value being lower than an open circuit voltage of the PV array, and then the PV array at its open circuit voltage is directly connected to the DC link, while the link voltage is continuously adjusted to the pre-set value.

Abstract: Power management circuitry (7-2,3,4) for converting a harvested voltage (Vhrv) to an output voltage (VBAT) applied to a battery (6) includes an inductor (L0) having a first terminal (3) coupled to receive the harvested voltage (Vhrv) and a second terminal coupled to a first terminal of a first switch (S0). The power management circuitry transfers the current generated by an energy harvester (2) to the battery if it (6) is not fully charged, and shunts the current away from the battery (6) to avoid overcharging if it is fully charged.

Abstract: An electronic assembly with two battery units includes a system module provided with a preset threshold value and a parallel circuit. The parallel circuit is coupled electrically to the system module, and includes first and second power diverter circuits. Each of first and second power diverter circuit consists of a diode member coupled electrically to a respective battery unit and the system module and an operation switch that is coupled electrically to the diode member in parallel manner and that is coupled electrically to the respective battery unit and the system module in such a manner that a normal bias voltage is existed between the respective battery unit and the system module.

Abstract: A marine power system comprises a motor for providing propulsion. It also comprises an energy storage unit (ESU) for storing and supplying energy to the motor. A prime power system is connected to the ESU and motor for selectively providing energy to these subsystems through a bus. The motor selectively receives energy from the prime power system and the ESU and can supply regenerative braking energy to the bus. The system can also accommodate multiple generator sets providing system power. The ESU can also provide starting power for the prime power system. Alternately, the prime power system drives a mechanical power system output shaft connected to the motor, and the marine system comprises an alternator driven by the prime power system output shaft. The ESU can transmit energy to the alternator. The prime power system can be located on a tugboat displacing a barge carrying the energy storage unit.

Abstract: A power source switching circuit includes a main source input terminal, an auxiliary source input terminal, a control circuit, a first switch, a second switch, and an output terminal. The control circuit is connected to the main source input terminal and the auxiliary source input terminal. The first switch is connected to the main source input terminal and the control circuit. The second switch is connected to the auxiliary source input terminal and the control circuit. The output terminal is connected to the first switch and the second switch. When the main source input terminal is at high level, the auxiliary source input terminal remains high level, the first switch is turned on, and the second switch is turned off by the control circuit.

Abstract: In an apparatus for connecting two generators to an electrical load, there are provided a first group of terminals that are adapted to be connected to a single remote controller provided independently and separately from the apparatus and provided with a start switch and a stop switch to be manipulated by an operator, a second group of terminals that are adapted to be connected to each remote control terminal of the generators, and an electronic control unit that is connected to the first and second group of terminals and starts/stops each of the generators by outputting signals to each of the generators through the second group of terminals in accordance with a start instruction signal and a stop instruction signal produced in response to the operator's manipulation of the start switch and stop switch and inputted through the first group of terminals, thereby enabling to start and stop generators to be run in parallel by using a single remote controller.

Abstract: Photovoltaic device comprising a photovoltaic generator comprising a number of photovoltaic cells, characterized in that it comprises at least one switch with a control device comprising a control capacitor (Ccde) and a control resistor (Rcde), linked to the switch so as to slow down the control of the opening of the switch, to allow at least one cell of the photovoltaic generator to switch from a short-circuit operating mode to an open-circuit mode, or vice versa.

Abstract: An output buffer is provided, to which first and second input signals are applied and that delivers an output signal. The output buffer includes a second offset switching stage installed in cascade downstream from a first switching stage. The second offset switching stage generates control points shifted in time with respect to memory points.

Abstract: An apparatus, system, and method are disclosed for providing alternating current (“AC”) power redundancy in power supplies. A first input module is configured to receive a first AC power input waveform. A second input module is configured to receive a second AC power input waveform. A first switch and second switch are controlled by a switching logic module to select one of the AC power input waveforms for use by a power supply. If the first AC power input waveform is present, then it is selected for use. If both the first and second AC power input waveforms are present, then the first AC power input waveform is selected for use. If only the second AC power input waveform is present then it is selected for use.

Abstract: A UPS is operated by deasserting a static switch drive signal, e.g., a gate signal to a thyristor, and then delaying provision of power from a converter circuit of the UPS, e.g., an inverter or other source of AC power, until after the switch has current commutated to an off state. For example, expiration of a predetermined time interval following deassertion of the switch drive signal may be detected, and the converter circuit may be enabled to drive the output of the UPS responsive to the detected expiration of the predetermined time interval. Alternatively, a current in the static switch may be detected, and the converter circuit may be enabled to drive the output of the UPS responsive to the detected current. The invention may be embodied as methods and apparatus.

Abstract: A compressor monitoring system includes current and voltage monitors, current and voltage averaging modules, a control module, and a switch. The current monitor measures a current drawn by a motor of a compressor. The current averaging module generates first and second average current values based on the current measured by the current monitor. The voltage monitor measures a utility power voltage. The voltage averaging module generates first and second average voltage values based on the voltage measured by the voltage monitor. The control module selectively generates a fault signal when a first ratio is greater than a first predetermined threshold and a second ratio is less than a second predetermined threshold. The first ratio is based on the first and second average current values. The second ratio is based on the first and second average voltage values. The switch deactivates the motor when the fault signal is generated.

Abstract: A method for reducing electromagnetic interference radiated from a power supply arrangement. A plurality of switching mode power supply units are connected to an external device. Each switching mode power supply unit includes a ground point. The radiated electromagnetic interference is reduced by synchronizing a switching frequency of each switching mode power supply unit, such that all of the synchronized switching mode power supply units have an identical switching frequency, thereby reducing the difference in electric potential between the ground points. A corresponding power supply arrangement.

Abstract: Methods, systems, and apparatuses for alternate power delivery are provided. A metering assembly includes a power meter module. The power meter module includes a power control module and a power monitor. The power control module is coupled to a transfer switch that receives both primary power and alternate power. The transfer switch has an output coupled to an electrical circuit load. The power control module is configured to receive a request from the transfer switch for the alternate power to be supplied through the transfer switch to the electrical circuit load. The power control module is configured to enable the transfer switch to supply the alternate power to the electrical circuit load in response to the request. The power monitor is configured to determine an amount of the alternate power provided to the electrical circuit load.

Abstract: A power system for connecting a variable voltage power source, such as a power controller, with a plurality of energy storage devices, at least two of which have a different initial voltage than the output voltage of the variable voltage power source. The power system includes a controller that increases the output voltage of the variable voltage power source. When such output voltage is substantially equal to the initial voltage of a first one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the first one of the energy storage devices. The controller then causes the output voltage of the variable voltage power source to continue increasing. When the output voltage is substantially equal to the initial voltage of a second one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the second one of the energy storage devices.

Abstract: A power cycler apparatus monitors a computer network for internet connectivity and cycles the power to connected networking devices when a loss of internet connectivity is detected. The power cycler may comprise remote power switches for resetting power to networking devices in remote locations. The power cycler may comprise a manual reset button for manually triggering a power reset cycle, which may be connected via a wired or wireless connection. The power cycler may restore power to the power outputs in a staggered fashion to allow each connected network device time to initialize before the next network device is powered on. The power cycler may feature a battery backup or uninterruptible power supply.

Abstract: Systems and methods for monitoring power devices that are connecting in a loop to a main power line are provided. A plurality of power devices that are connected in a loop to a power grid line may be provided. The loop may include a plurality of power lines. A disturbance within the plurality of power devices may be identified, and an impact of the identified disturbance on the plurality of power lines may be determined. A power output of one or more of the plurality of power devices may be adjusted based at least in part on the determined impact.

Abstract: A power system controller using a 2×2 decoupling controller, a model reference, and feedback with delay. Embodiments provide control of microgrid frequency F and voltage V. In addition, this technique can also be used to control the real and reactive power delivered from the microgrid to the connected macrogrid. The control engineering approach is the same in both cases, but the roles of the four variables involved are reversed.

Abstract: A scalable highest available voltage selector circuit determines the highest of n input voltages and connects the highest voltage to an output. The circuit has at least n circuit branches, each of which comprises n?1 “comparator” FETs connected between an input voltage and an output node, and a diode-connected FET connected between the output node and a current source. The junction of the diode-connected transistor and current source provides a control signal used by the other branches. Each of a branch's comparator FETs have their gates connected to a respective one of the other branches' control signals, such that they are driven on regeneratively when the applied input voltage is the highest of the n input voltages. Each branch also includes n?1 “shorting” FETs connected across the diode-connected transistor, arranged to be driven off when the applied input voltage is the highest, but which are otherwise driven on.

Abstract: A system and method for pre-detection in a power over Ethernet (PoE) system. A power sourcing equipment (PSE) is designed to measure a port voltage upon application of a small current source. A microcontroller controls the current source based on a comparison of the measured port voltage to a threshold voltage.

Abstract: An electrical power system architecture uses an auxiliary power unit as an electrical power source during taxi (ground idle) and approach idle (if required). Using the APU as a power source enables a low pressure spool driven electrical generator to be off-line when its speed is too low for it to operate effectively.

Abstract: An uninterruptible power supply device connects a battery for power-outage backup to the output side of an AC/DC converter. An input monitoring circuit monitors alternating current input of the AC/DC converter and outputs an alternating current input monitor signal E1. An output monitoring circuit monitors the direct current output of the AC/DC converter and outputs a direct current output monitor signal E2. A reactivation circuit outputs a reset signal to and reactivates protection circuits of the AC/DC converter when the state that alternating current input is provided and direct current output is not provided is determined based on the alternating current input monitor signal E1 and the direct current output monitor signal E2 upon turn-on of alternating current power.

Abstract: An object is to provide a duplex power supply for auxiliary machines. A power supply device includes a switching section that is connected to a direct-current link between a generator-side inverter and a grid-side inverter via an auxiliary machine power inverter for converting direct-current power supplied from the direct-current link into alternating-current power to form a first path, that is connected somewhere between a power-converting section and a utility grid to form a second path, and that is connected to auxiliary machines to form a third path, and the switching section switches between connection of the third path to the first path and connection of the third path to the second path.

Abstract: Distributed generation systems incorporate a distribution network and typically a number of distributed generators. It is possible that power islands may be created in substations incorporating a generator when that substation and generator is isolated from the distribution network by a circuit breaker. A problem arises when the power island is re-connected to the distribution network when the phase of electrical power supply in the previous power island is not synchronized with the power supply on the distribution network. Identifying such an out of phase nature is achieved utilizing application of test reactances, both capacitative and inductive, across the whole distribution network such that such test reactances are substantially unbalanced within a particular substation and in particular a distribution path for a generator so that there is a test reactance load imbalance which will identify out of phase operation and therefore control activation of the circuit breaker.

Abstract: An energy transfer circuit for connecting a load to multiple energy sources that can have different voltages. The energy transfer circuit connects the load and at least two energy sources, and has a control unit. The energy transfer circuit can transfer energy from at least one energy source to the load in response to the load's power demand; transfer energy from the load to at least one energy source in response to the load's charging current, and transfer energy between the energy sources. The energy transfer circuit also includes a first capacitor in parallel with the primary source and the load; a second capacitor in parallel with the secondary source, an inductor, a first switch between the inductor and the first capacitor, a second switch between the inductor and the second capacitor. The control unit opens and closes the first and second switches in response to the load and sources.

Abstract: A power supply selection/detection circuit to select one main power supply from a plurality of external power supplies includes a resistance element with one end connected to an external power supply and another end connected to the main power supply, a first voltage detector to receive a voltage of the external power supply and detect a voltage of the external power supply, a second voltage detector to detect a voltage between the ends of the resistance element, and a switch connected between the external power supply and a ground to short-circuit or open-circuit between the external power supply and the ground according to an output of the second voltage detector. The resistance element and the first voltage detector are disposed for each of the plurality of external power supplies, and the second voltage detector and the switch are disposed for at least one of the plurality of external power supplies.

Abstract: A system and method that offers the provision too rapidly and safely connect electrical generation sources, including inverters used by solar collecting panels, or wind turbines, and backup hydrocarbon fueled generators or any other supplemental power sources including storage batteries, fuel cells and future electric automobiles. Thus enabling the feeding of power to all circuits in the home or small business, not just isolated circuits in a structure. The system is compliant with electric codes, requires no costly rewiring inside the structure or in the electrical circuit panel and can be accomplished entirely from the outside of the home or small business adjacent to the electric service meter for the home or small business structure.

Abstract: A variable frequency transformer including: a first parallel circuit including at least two of the rotary transformers arranged in parallel and having an isolating circuit breaker connected to a rotor winding of each of the rotary transformers, and a separate synchronizing circuit breaker connected to a stator winding in each of the rotary transformers in the first parallel circuit; a first main transformer having a first winding connectable to a first power grid and a secondary winding connectable to the isolating circuit breaker in the first parallel circuit; a second main transformer having a first winding connectable to a second power grid and a secondary winding connectable to each of the synchronizing circuit breakers in the first parallel circuit, and a control system operatively connected to each of the synchronizing circuit breakers, the isolating circuit breakers and the drive motors for each of the rotary transformers.

Abstract: A load driving circuit that generates a desired voltage waveform to drive a load includes a target voltage waveform output section that outputs a target voltage waveform to be applied to the load. Power supply sections generate electrical power with voltage values different from each other. Negative feedback control sections between the power supply sections and the load supply electrical power from the corresponding power supply sections to the load and execute negative feedback control of a value of a voltage applied to the load for matching the voltage value and the target voltage waveform. A power supply connection section selects one of the power supply sections based on the value of the voltage applied to the load or the voltage value of the target voltage waveform and connects the selected power supply section to the load and disconnects the rest of the power supply sections from the load.

Abstract: A method is disclosed for producing electrical current by a fuel cell device, which inputs electrical current to an electrical network. A fuel cell device can be arranged to be parallel connected to the electrical network. A phase reference signal can be utilized in the inputting of the electrical current, and electrical current inputted to electrical network can be current controlled by a power transformer having a power stage. The fuel cell device can be switched off from the electrical network when a malfunction occurs in the electrical network. The fuel cell device can be changed, using the phase reference signal, to the switched off operation mode for performing voltage controlled operation of the power transformer. A controllable load can be used for maintaining a power stability between the voltage controlled power transformer and other parts of the fuel cell device.

Abstract: A selectable backup power supply device for providing power to a real time clock (RTC) and a memory unit is disclosed. The device includes a backup battery, a first power outputting unit and a second power outputting unit, wherein the backup battery outputs a backup voltage, the first power outputting unit is connected to the backup battery and the RTC for receiving the backup voltage and outputting a first supply voltage to the RTC, and the second power outputting unit is connected to the backup battery and the memory unit, for receiving the backup voltage and, in accordance with a selection signal, outputting a second supply voltage to the memory unit or stopping the output of the second supply voltage.