Abstract: A voltage equalizer includes: first, second, and third junction terminals respectively connected to a positive electrode of a first battery module, a positive electrode of a second battery module, and negative electrodes of the first and second battery modules; an equalizer circuit connected between the first and second junction terminals, and the equalizer forming a current path between the first and second junction terminals; a first indicator having a first displaying state that changes according to a voltage difference between the first and second junction terminals; a first comparator for outputting a first output voltage according to an input voltage that is input in proportion to a voltage between the first and third junction terminals; and a second indicator having a second displaying state that changes according to the first output voltage of the first comparator.

Abstract: Module-based energy systems are provided having multiple converter-source modules. The converter-source modules can each include an energy source and a converter. The systems can further include control circuitry for the modules. The modules can be arranged in various ways to provide single phase AC, multi-phase AC, and/or DC outputs. Each module can be independently monitored and controlled.

Abstract: A balance circuit for a set of battery cells includes a set of switch circuits and control circuitry coupled to the switch circuits. Each switch circuit of the switch circuits is coupled to a corresponding battery cell of the battery cells, and enables a bypass current to flow out a positive terminal of the corresponding battery cell if the switch circuit is turned on. The switch circuit includes a first switch having a first diode and a second switch having a second diode reversely coupled to the first diode. The second switch disables the bypass current if the second switch is turned off. The control circuitry balances the battery cells by controlling the switch circuits.

Abstract: A multilevel inverter includes an inner DC source group circuit that generates a plurality of voltage levels, and an outer DC source group circuit that generates a substantially sinusoidal output voltage. The substantially sinusoidal output voltage is generated using, at least in part, the plurality of voltage levels generated by the inner DC source group circuit. An H-bridge circuit supplies the substantially sinusoidal output voltage at alternating polarities to a load.

Abstract: A solar cell management system for increasing the efficiency and power output of a solar cell and methods for making and using the same. The management system provides an electric field across an individual solar cell, an array of solar cells configured as a panel, or a group of solar panels. The imposed electric field exerts a force on both the electrons and holes created by light incident on the solar cell and accelerates the electron-hole pairs towards the electrodes of the solar cell. Compared to conventional solar cells, these accelerated electron-hole pairs travel a shorter distance from creation (by incident optical radiation) and spend less time within the solar cell material, therefore the electron-hole pairs have a lower likelihood of recombining within the cells' semiconductor's material. This reduction in the electron-hole recombination rate results in an overall increase in the solar cells' efficiency and greater power output.

Abstract: A single-phase hybrid multilevel inverter capable of producing a higher number of output voltage levels using fewer power switches and DC voltage sources compared to existing multilevel inverters. The levels are synthesized by switching the DC voltage sources in series/parallel combinations. An auxiliary circuit is introduced to double the number of levels by creating an intermediate step in between two levels. In addition, a zero level is introduced to overcome the inherent absence of this level in the original circuit. To improve the total harmonic distortion, a hybrid modulation technique is utilized. A 300 W, a thirteen level multilevel inverter (including the zero level) was designed and constructed. The circuit was tested with a no-load, resistive load and resistive-inductive load. The experimental results closely match simulated and mathematical analyses.

Abstract: An energy storage system comprising a main bus, a transfer bus, and a pair of anti-parallel thyristors electrically coupled to the main bus and the transfer bus. The system also includes a first and second group of battery cells electrically coupled to the main bus and the transfer bus, and a switching network including a plurality of switches that selectively connect the first and second groups of battery cells to the main bus and the transfer bus. A controller controls the position of the switches and a bias voltage applied to the first and second thyristors so as to seamlessly transition power from the first group of battery cells to the second group of battery cells when the group of battery cells are being discharged and seamlessly transition power between the first group of battery cells and the second group of battery cells when the battery cells are being charged.

Abstract: An apparatus may include a group of distributed-input series-output (DISO) converters, each of which are actively controlled by a common maximum power tracking (MPT) controller. The common MPT controller is configured to actively control one of the DISO converters in the group of DISO converters to update a present group-peak power voltage of the one DISO converters while remaining DISO converters in the group of DISO converters are controlled to hold most recently grouped peak power voltages updated during their previously non-overlapping uniform time windows of active MPT control.

Abstract: Systems for converting a standard direct current (DC) power from solar panels into a rectified DC power signal for further conversion into alternating current (AC) power are described herein. In some example embodiments, the systems may include distributed power converters and a grid interface unit connected by a trunk cable. In some example embodiments, the power converters may be embedded in the trunk cable.

Abstract: A power conversion system comprises a plurality of power converter modules, each including a bi-directional DC to DC converter and a current controller, wherein the bi-directional DC to DC converter is connected to the current controller, for charging or discharging a DC power source according to a distribution command received from the current controller, and a voltage controller, connecting to the plurality of power converter modules, for generating a current command to the current controller, wherein the voltage controller generates a current command to the current controller of the power converter module according to the detected capacity and voltage of the DC power source, whereby the current controller generates the distribution command to the bi-directional DC to DC converter with the received current command.

Abstract: A multilevel inverter includes an inner DC source group circuit that generates a plurality of voltage levels, and an outer DC source group circuit that generates a substantially sinusoidal output voltage. The substantially sinusoidal output voltage is generated using, at least in part, the plurality of voltage levels generated by the inner DC source group circuit. An H-bridge circuit supplies the substantially sinusoidal output voltage at alternating polarities to a load.

Abstract: A multilevel inverter includes an inner DC source group circuit that generates a plurality of voltage levels, and an outer DC source group circuit that generates a substantially sinusoidal output voltage. The substantially sinusoidal output voltage is generated using, at least in part, the plurality of voltage levels generated by the inner DC source group circuit. An H-bridge circuit supplies the substantially sinusoidal output voltage at alternating polarities to a load.

Abstract: Tailoring the emission spectra of a solar thermophotovoltaic emitter away from that of a blackbody, thereby minimizing transmission and thermalization loss in the energy receiver, is a viable approach to circumventing the Shockley-Queisser limit to single junction solar energy conversion. Embodiments allow for radically tuned selective thermal emission that leverages the interplay between two resonant phenomena in a simple planar structure—absorption in weakly-absorbing thin films and reflection in multi-layer dielectric stacks. A virtual screening approach is employed based on Pareto optimality to identify a small number of promising structures for a selective thermal emitter from a search space of millions, several of which approach the ideal values of a step-function selective thermal emitter.

Abstract: According to one embodiment, a solar cell system includes a first solar cell including a first terminal and a second terminal, a second solar cell including a third terminal and a fourth terminal, and a voltage converter including a fifth terminal and a sixth terminal. The third terminal is electrically connected to the first terminal. The fifth terminal is electrically connected to the fourth terminal. The voltage converter causes a second absolute value to be smaller than a first absolute value. The first absolute value is of a difference between a first potential difference and a second potential difference. The first potential difference is between the first and second terminals. The second potential difference is between the first and fourth terminals. The second absolute value is of a difference between the first and third potential differences. The third potential difference is between the first and sixth terminals.

Abstract: A photovoltaic (PV) module sub-circuit for an energy generation system includes a plurality of PV sub-modules coupled together via external cables, the plurality of PV sub-modules includes a first PV sub-module and a second PV sub-module, a negative output terminal coupled to the first PV sub-module, a positive output terminal coupled to the second PV sub-module, and a plurality of connectors external to the PV sub-modules and coupling the PV sub-modules together to form the PV module sub-circuit. The sub-circuit further includes a bypass mechanism including a first terminal coupled to only the negative output terminal and the first PV sub-module, and a second terminal coupled to only the positive output terminal and the second PV sub-module, the bypass mechanism configured to prevent current flow in a first direction and allow current flow in a second direction opposite of the first direction.

Abstract: Controlling a power converter circuit for a direct current (DC) power source is disclosed. The power converter may be operative to convert input power received from the DC power source to an output power and to perform maximum power point tracking of the power source. The power converter is adapted to provide the output power to a load that also performs maximum power point tracking.

Abstract: The installation comprises: a DC-generating arrangement formed by electrical generators (PV1 . . . PVn) which are connected in series and located inside a local area, and supply a remote area with a total direct current that is the sum of the current generated by each of the electrical generators (PV1 . . . PVn); and an auxiliary power supply device (D) which is arranged inside the local area and provides the auxiliary system (E) with a supply voltage in the local area, wherein the auxiliary power supply device (D) is made up of a current-fed power converter (CP) electrically connected in series, respective input terminals (T1, T2), in the DC-generating arrangement between two connection points (p1, p2) of the electrical generators, located inside the local area.

Abstract: Introduced here are several embodiments of network switch modules having interfaces designed to enable use of different voltages or currents. Accordingly, a network switch may be able to support both optical interfaces and electrical interfaces on the same printed circuit board (e.g., a line card or a fabric card). In some embodiments, the printed circuit board includes a “booster stage” electrical interface that is designed specifically for optical interfaces. Such a design enables the components of a switch to operate with both electrical interfaces and optical interfaces.

Abstract: A photovoltaic power generation plant includes a plurality of photovoltaic generators cooperative in producing photovoltaic power. Coupled with the photovoltaic generators in the plurality of photovoltaic generators are respective sensor devices, the sensor devices including sensor circuits of the individual current-to-voltage characteristics of the photovoltaic generators. The sensor circuits in the sensor devices can be activated to sense the individual current-to-voltage characteristics of the photovoltaic generators, with the individual current-to-voltage characteristic being indicative of the functionality of each photovoltaic generator.

Abstract: A bidirectional insulated DC/DC converter includes a first single-phase 3-level inverter, a second single-phase 3-level inverter, and an insulated transformer. The first single-phase 3-level inverter generates a first AC voltage between output terminals based on a first DC voltage received from a first DC circuit. The second single-phase 3-level inverter generates a second AC voltage between output terminals based on a second DC voltage received from a second DC circuit. The insulated transformer includes a primary winding that receives the first AC voltage from the output terminals and a secondary winding that receives the second AC voltage from the output terminals.

Abstract: A circuit for controlling a first plurality of transistors connected in parallel and a second plurality of transistors connected in parallel, includes: a first plurality of stages, a respective one of the first plurality of stages being configured to supply a first control signal to a respective one of the first plurality of transistors; and a second plurality of stages, a respective one of the second plurality of stages being configured to supply a second control signal to a respective one of the second plurality of transistors. An output current of the respective one of the first plurality of stages is regulated based on a difference between a first value representative of a sum of output currents of each stage of the first plurality of stages and a second value representative of a sum of set points assigned to the first plurality of stages.

Abstract: The present disclosure provides a control method for improving conversion efficiency of a multi-channel MPPT input inverter, which implements high efficient operation of the inverter.

Abstract: A multiphase power converter circuit includes at least two single phase power converter circuits. Each single phase power converter circuit includes at least one converter series circuit with a number of converter units. The converter series circuit is configured to output a series circuit output current. A synchronization circuit is configured to generate at least one synchronization signal. At least one of the converter units is configured to generate an output current such that at least one of a frequency and a phase of the output current is dependent on the synchronization signal.

Abstract: A control unit of a power conversion device calculates a current target value and a voltage target value for a DC/AC converter on the basis of an output current target value, to control the DC/AC converter, and calculates a current target value for the DC/DC converter on the basis of the current target value and the voltage target value, and a voltage target value for the DC/DC converter, to control the DC/DC converter, thereby controlling output of an AC power. The control unit selects, as the voltage target value for the DC/DC converter, a greatest value at a present time, from among a DC voltage value of the DC power supply, an absolute value of a voltage target value for an AC side of the DC/AC converter, and a DC voltage lower limit value which is a predetermined value smaller than a peak value of the absolute value.

Abstract: A photovoltaic (PV) system includes a system control module that determines the presence of a microinverter chain termination end cap. The end cap includes an embedded circuit. The embedded circuit includes components having resistive, reactive, or impedance values. A signal source provides a signal through the microinverter chain. A parameter for a sensed signal detected by the system control module is used to determine the presence of the end cap using a change between the parameter for the sense signal and a reference parameter.

Abstract: A voltage balancing circuit is applied to a power supply system. The power supply system comprises N power storage devices. The voltage balancing circuit comprises: N switches, N capacitors and a controller; the N switches are respectively connected to the N serial power storage devices; the N switches are respectively connected to the first terminals of the N capacitors; the second terminals of the N capacitors are connected to a common neutral line; the controller is connected to the N switches through a control line to control the switching of the N switches. The voltage balancing circuit avoids power loss when balancing the voltage of a plurality of serial power storage devices, and is small in size and low-cost, and balances voltage quickly.

Abstract: A battery assembly device with charging and discharging protection is provided. The aforementioned device includes a plurality of serially connected battery modules and each of the battery module further includes one or a plurality of battery units, a plurality of serially connected first diodes which are parallel connected with the battery unit, a protection circuit including a second diode and third diode which are parallel connected to each other, and a fourth diode. Aforementioned protection circuit is serially connected with the battery unit and configured between two connection points of the battery module, electrode polarity of the second diode and electrode polarity of third diode at connection point are different, and the fourth diode are configured between the two connection points of the battery module and its electrode polarity are different with the connection point of the battery unit.

Abstract: A converter includes a plurality of switching elements, at least one capacitance, and a resonant circuit. The plurality of switching elements include a first switching element coupled to a first control signal line that controls switching of the first switching element, a second switching element coupled to a second control signal line that controls switching of the second switching element, a third switching element coupled to a third control signal line that controls switching of the third switching element, and a fourth switching element coupled to a fourth control signal line that controls switching of the fourth switching element. The plurality of switching elements, the resonant circuit, and the at least one capacitance operate to convert a first voltage into a second voltage that charges a first battery and a second battery.

Abstract: A power source is configured to include a plurality of batteries and a switching circuit that switches a state to and from a first state in which the electric power is supplied to the outside by the plurality of batteries being connected in series and a second state in which the electric power is supplied to the outside using remaining batteries without using a part of the plurality of batteries.

Abstract: A photovoltaic system includes voltage limiting devices that are connected in series. A voltage limiting device clips a corresponding photovoltaic string to limit a voltage of the photovoltaic string. Unclipping of clipped photovoltaic strings is coordinated by a central controller or in a distributed fashion by the voltage limiting devices based on monitored string conditions.

Abstract: An energy storage device and a DC voltage supply circuit. The energy storage device has at least two energy supply branches connected in parallel. Each of the energy supply branches has a multiplicity of energy storage modules having an energy storage cell module with at least one energy storage cell and a coupling device. The coupling device switches the energy storage cell module selectively into the corresponding energy supply branch or bypasses said energy storage cell module in the energy supply branch. The DC voltage supply circuit has a bridge circuit switchably connected to a first or a second of feed nodes coupled to output connections of the energy storage device.

Abstract: A method of estimating a line voltage is provided that includes configuring a capacitive probe to a power line, injecting a perturbation voltage onto the capacitive probe, where the perturbation voltage has a different frequency than a frequency of the line voltage, measuring, using a capacitive sensor, a retrieved perturbation voltage, where the retrieved perturbation voltage is dependent on a capacitance between the capacitive probe and a ground capacitance, using an appropriately programmed computer to track real time changes in the capacitance of the capacitive probe, and estimating a line voltage.

Abstract: The hybrid partial power processing system includes differential power processing converters DPPs having low power ratings, which are used to exchange differential power between two adjacent PV modules, or between PV modules and a line capacitor (Clin) connected in series within the same string. The exchange of differential power by DPPs is needed to track the maximum power point of each PV module in the string. The DC power optimizing converter (DC-PO) is a DC/DC power converter used to feed current (power) from a PV module to Clin. The DC-PO is driven to track the maximum power point (MPP) of one PV module, and the MPP of each one of the remaining PV modules in the string is tracked by a DPP.

Abstract: Disclosed is a power control system for a plurality of energy storage devices, including: a first converter configured to perform a voltage conversion, the first converter having one end connected to a first power system and another end connected to a direct current (DC) linker; a second converter configured to perform a voltage conversion, the second converter having one end connected to a second power system and another end connected to the DC linker; a first energy storage device configured to store electric energy; a direct current-to-direct current (DC-DC) converter configured to perform a voltage conversion, the DC-DC converter having one end connected to the first energy storage device and another end connected to the DC linker; a second energy storage device connected to the DC linker and configured to store electric energy, and a control device.

Abstract: A system and method for combining power from DC power sources. Each power source is coupled to a converter. Each converter converts input power to output power by monitoring and maintaining the input power at a maximum power point. Substantially all input power is converted to the output power, and the controlling is performed by allowing output voltage of the converter to vary. The converters are coupled in series. An inverter is connected in parallel with the series connection of the converters and inverts a DC input to the inverter from the converters into an AC output. The inverter maintains the voltage at the inverter input at a desirable voltage by varying the amount of the series current drawn from the converters. The series current and the output power of the converters, determine the output voltage at each converter.

Abstract: In order to distribute power over multiple direct current sources which are connected in parallel to an input-side direct voltage intermediate circuit of a DC/AC transformer, at least one of which direct current sources is connected to the direct voltage intermediate circuit via a DC/DC transformer, wherein the DC/DC transformer can be actuated to change the power fed into the direct voltage intermediate circuit by the direct current source, the power levels of the direct current sources are decreased differently in a decreased operating mode of the DC/AC transformer in which the power of the DC/AC transformer is decreased compared to the sum of the maximum power levels available from all the direct current sources, and by actuating at least the one DC/DC transformer via which the at least one direct current source is connected to the direct voltage intermediate circuit, variation in the power levels of at least one other direct current source is compensated dynamically.

Abstract: A monitoring and shutdown device for a solar photovoltaic (PV) module (20) has a control switch (11), a micro control unit (MCU) (10), a voltage acquisition unit (13), a temperature acquisition unit (14) and a power line communication (PLC) module (15). The control switch (11) connects to a power series circuit of the PV module. Output terminals of the voltage acquisition unit (13) and the temperature acquisition unit (14) connect to the MCU. The voltage acquisition unit (13) and the PLC module (20) connect to the power series circuit. The MCU (10) connects to the control switch (11), and determines whether over-voltage or over-temperature occurs to the PV module (20) by the voltage and temperature acquisition units (13, 14). For abnormal conditions, the MCU (10) sends a notification through the PLC module (15), and disconnects the PV module (20) from the power series circuit by the control switch (11).

Abstract: A method and module for monitoring a voltage of a power cell, sampling and holding a voltage of the power cell, and balancing a voltage of the power cell. In accordance with an embodiment, an interface circuit is capable of operation in a plurality of operating modes. In accordance with another embodiment, the interface circuit is coupled to a filter section.

Abstract: This disclosure generally relates to an energy generation system. In one embodiment, the energy generation system comprises a plurality of solar panels that are connected in a series electrical connection. The energy generation system further includes a short-string optimizer which outputs direct current electricity to a direct current bus.

Abstract: A method for forming and operating a multi-terminal power system, includes: connecting multiple sending terminals to a network of a power system; and local control of each sending terminal to behave as a constant-power source such that both output voltage and output current of the sending terminal may simultaneously vary in response to changing external circuit conditions while maintaining constant a product of the output voltage and the output current of the sending terminal. At least one sending terminal may include a capacitive output converter having a capacitor connected between two output terminals and a controlled current source connected in parallel to the capacitor, or an inductive output converter having an inductor connected to an output terminal and a controlled voltage source connected in series with the inductor.

Abstract: A photovoltaic panel with multiple photovoltaic sub-strings including serially-connected photovoltaic cells and having direct current (DC) outputs adapted for interconnection in parallel into a parallel-connected DC power source. A direct current (DC) power converter including input terminals and output terminals is adapted for coupling to the parallel-connected DC power source and for converting an input power received at the input terminals to an output power at the output terminals. The direct current (DC) power converter optionally has a control loop configured to set the input power received at the input terminals according to a previously determined criterion. The control loop may be adapted to receive a feedback signal from the input terminals for maximizing the input power. A bypass diode is typically connected in shunt across the input terminals of the converter. The bypass diode functions by passing current during a failure of any of the sub-strings and/or a partial shading of the sub-strings.

Abstract: Three or more photovoltaic cell units connected in series include a unit holding a voltage between output terminals, a first voltage holding unit group having a voltage holding unit holding a voltage between an anode-side terminal and a cathode-side terminal for each photovoltaic cell unit set with respect to each set of the (2k+1)th and (2k+2)th photovoltaic cell units connected in series to each other counted from the anode side, and a second voltage holding unit group having a voltage holding unit holding a voltage between an anode-side terminal and a cathode-side terminal for each photovoltaic cell unit set with respect to each set of the (2k+2)th and (2k+3)th photovoltaic cell units connected in series to each other counted from the anode side.

Abstract: Controlling a power converter circuit for a direct current (DC) power source is disclosed. The power converter may be operative to convert input power received from the DC power source to an output power and to perform maximum power point tracking of the power source. The power converter is adapted to provide the output power to a load that also performs maximum power point tracking.

Abstract: A method and apparatus for independently controlling multiple power converter sources. In one embodiment, the method comprises determining a ratio of a first set point for biasing a first DC source to a power converter and a second set point for biasing a second DC source to the power converter, wherein the first and the second DC sources are serially-coupled to one another and coupled to an input bridge of the power converter by a filter; and determining, based on the ratio, relative switching times for driving a first diagonal of an input bridge of the power converter and a second diagonal of the input bridge to bias the first DC source proximate the first set point and the second DC source proximate the second set point.

Abstract: An energy storage system includes: a plurality of slave power controllers connected to respective battery modules; and a master power controller configured to transmit a first signal to the plurality of slave power controllers and transmit a second signal for controlling synchronizations of the plurality of slave power controllers to the plurality of salve power controllers according to a reception time at which each of the plurality of salve power controllers receives the first signal.

Abstract: A network apparatus architecture is disclosed that includes one or more isolation circuits to accommodate a predetermined isolation voltage. Each isolation circuit enables an independent DC voltage to be selected along a network signaling path to accommodate different DC voltages of network circuits along the network signaling path. For example, DC isolation may be provided between a physical interface and a network circuit via one or more capacitors, optoelectronic isolators, coupled magnetic devices, or semiconductor devices. A network circuit may be powered by a power supply that is isolated from the rest of the network apparatus. The one or more isolation circuits and network circuits may be included in a system-on-chip, or application-specific integrated circuit.

Abstract: Systems and methods for modeling an electrical power system are disclosed. A computer and an analytics server are in network connection. The computer comprises a processor coupled with a memory. The memory is configured to maintain at least one engine element and a component database. The analytics server comprises a virtual system modeling engine and an analytics engine. The component database is operable to store power system components. The at least one engine element is operable to generate a virtual system model of the electrical power system and generate predicted output based on the virtual system model. The analytics engine is operable to monitor the predicted output and real-time output from at least one sensor of the electrical power system, and calibrate the virtual system model based on a difference between the predicted output and the real-time output.

Abstract: The invention relates to a system having an energy storage device and a DC voltage supply circuit, wherein the energy storage device has at least two energy supply branches, which are each coupled at a first output to at least one respective output terminal of the energy storage device in order to generate an AC voltage at the output terminals, and at a second output to a shared bus, wherein each of the energy supply branches has a plurality of energy storage modules connected in series. The energy storage modules each comprise an energy storage cell module having at least one energy storage cell and a coupling device having a coupling bridge circuit made from coupling elements. The coupling elements are designed to selectively connect the energy storage cell module to the respective energy supply branch or to bypass the energy supply branch.

Abstract: A battery monitoring device monitors a battery having a plurality of cell groups in which a plurality of cells is connected in series. The battery monitoring device comprises at one or more integrated circuit units, each of which corresponds to each cell group, that respectively measure the voltages of the cells of the cell group and performs cell balancing in order to adjust the capacities of the cells of the cell group; a control unit that controls the integrated circuit unit; and a power supply unit that supplies power to the control unit. The control unit causes the integrated circuit unit to start or to stop cell balancing, and sets a timer period for starting or stopping supply of the power.

Abstract: In order to protect reverse currents, several strings of a photovoltaic generator, which are connected in small groups respectively via a DC/DC-converter, parallel to a common DC voltage intermediate circuit, the current which flows over each of the DC/DC-converter is detected and if a reverse current is detected flowing through one of the DC/DC converters, the converter is stopped by controlling the DC/DC-converter.