Abstract: An insulated gate field effect transistor (IGFET) based converter circuit is described that includes a direct current input comprising a high voltage input and a low voltage input, an IGFET gate input, and an equivalent phase leg comprising a plurality of parallel-connected cells. The parallel-connected cells each include: a first wide bandgap IGFET having a first drain electrode connected to the high voltage input, a first gate electrode connected to a first gate control input, and a first source electrode; a second wide bandgap IGFET having a second drain electrode connected to the first source electrode, a second gate electrode connected to a second gate control input, and a second source electrode connected to the low voltage input; and a step-inducing inductor coupled to: the first source electrode of the first wide bandgap IGFET, and an output node. The step-inducing inductor is connected to the output node.

Abstract: A frequency support system arranged for providing frequency support to an AC grid. The system includes an ES arrangement, and a bi-directional DC/AC power electronic converter interface configured for connecting the ES arrangement with the grid. The ES arrangement includes a plurality of series connected ES groups, each ES group including a plurality of parallel connected ES modules, each ES module including an energy storage interfaced by a bi-directional power electronic ES converter configured for connecting the ES with a DC side of the converter interface.

Abstract: Systems, apparatuses, and methods are described for power conversion. The power conversion may be done by a plurality of power devices with different configurations. For example, the plurality of power devices may include one or more converters with an upside-up buck configuration and one or more converters with an upside-down buck configuration. The power conversion may be done by one or more power devices that may be configurable between different modes of configuration. For example, one or more power converters may be configured in either an upside-up buck configuration mode or an upside-down buck configuration mode. The selection of a certain mode of configuration of the converter may be permanent or non-permanent.

Abstract: Example embodiments of systems, devices, and methods are provided for electric vehicles that are subject to intermittent charging, such as rail-based electric vehicles, having one or more modular cascaded energy systems. The one or more modular systems can be configured to supply multiphase, single phase, and/or DC power to numerous motor and auxiliary loads of the EV. If multiple systems or subsystems are present in the EV, they can be interconnected to exchange energy between them in numerous different ways, such as through lines designated for carrying power from the intermittently connected charge source or through the presence of modules interconnected between arrays of the subsystems. The subsystems can be configured as subsystems that supply power for motor loads alone, motor loads in combination with auxiliary loads, and auxiliary loads alone.

Abstract: An adaptive control method for multiple inverters in parallel and a system with multiple inverters in parallel. The method average distribute the active power of each inverter unit by means of acquiring state information of inverter units, adjusting a reference voltage output by each of the inverter units based on a deviation between the output active power and the average active power, which is calculated by the state information, re-acquiring the state information and calculating a voltage component difference and a current component difference between the inverter units based on the adjusted reference voltage, and then adaptively adjusting the virtual impedance of the slave inverter unit according to the voltage component difference and the current component difference so that the output impedance of the slave inverter unit and master inverter unit is matched.

Abstract: The present disclosure provides a high-frequency uncontrolled rectifier-based DC transmission system for an offshore wind farm, including a DC system and an offshore AC system. The offshore AC system mainly includes wind turbines based on permanent magnet synchronous generators with full-scale power converters, AC submarine cables, and offshore step-up stations. The DC system includes an offshore station and an onshore station that are connected by DC submarine cables, where a converter of the offshore is a three-phase six-pulse uncontrolled rectifier bridge, while a converter of the onshore station is MMC. Each of the offshore AC system and the offshore station has a rated frequency far above 50 Hz, which can usually be chosen to be in a range of about 100 Hz to 400 Hz. The disclosed transmission system allows for a great reduction in construction costs and demonstrating great application potentials in actual engineering.

Abstract: A behind-the-meter system for controlled distribution of solar power to units in a multi-unit building connected to an electric power grid. The system includes a grid-tied inverter connectable between a solar power generator and the electric power grid sensors for measuring instantaneously power demand and solar power consumption of the units and solar power generation and switches for connecting and disconnecting the units from the solar power generator. A controller, connected to the sensors and the switches determines relative values of power demand and solar power consumption of the units based on the instantaneous measurements of the power demand and the solar power consumption, and controls the switches to distribute solar power from the solar power generator.

Abstract: Methods, apparatus, systems, and articles of manufacture are disclosed for regulated hybrid converters. An example apparatus includes an input terminal; an output terminal, a first converter circuit coupled between the input terminal and an intermediate node, the first converter circuit having a first switch node, a second converter circuit coupled between the intermediate node and the output terminal, the second converter circuit having a second switch node; a first inductor coupled between the first switch node and the second switch node, and a second inductor coupled between the second switch node and the output terminal.

Abstract: A power combining technique includes receiving a first voltage at a first input and a second voltage at a second input. The power combining technique further includes combining, with at least two power converters, power received from the first and second inputs into a single power rail. A power balancing technique further includes controlling the at least two power converters such that a first one of the power converters outputs an amount of current to the single power rail that is proportional to and/or equal to the amount of current output by another of the power converters.

Abstract: Disclosed is an adaptable DC-AC inverter system and its operation. The system includes multiple DC input sources as input to provide a stable operation under various conditions. DC input sources may be added to the system or removed from the system without impacting the functionality of the system. The disclosed system is suited for solar energy harvesting in grid-connected or off-grid modes of operation.

Abstract: A smart card inlay comprising an inductive antenna and a DC-DC converter. The inductive antenna is configured to (i) communicate wirelessly with a card terminal, and (ii) power card circuitry via inductive coupling to the card terminal. The DC-DC converter has an input coupled to the inductive antenna and an output connectable to card circuitry. The DC-DC converter is configured to receive an input power signal from the inductive antenna and convert that input power signal to an output power signal to send to the card circuitry, the output power signal matching the operating current and/or operating voltage of the card circuitry.

Abstract: Power distribution modules are configured to distribute power to a power-consuming component(s), such as a remote antenna unit(s) (RAU(s)). By “hot” connection and/or disconnection, the power distribution modules can be connected and/or disconnected from a power unit and/or a power-consuming component(s) while power is being provided to the power distribution modules. Power is not required to be disabled in the power unit before connection and/or disconnection of power distribution modules. The power distribution modules may be configured to protect against or reduce electrical arcing or electrical contact erosion that may otherwise result from “hot” connection and/or connection of the power distribution modules.

Abstract: A photovoltaic system includes a controller and plurality of photovoltaic strings that are independently controlled. The controller enables some photovoltaic strings to be in a maximum power point tracking state, and the remaining photovoltaic strings to be in a power output limited state. The system implements maximum power point tracking detection so that the maximum power point power and the maximum power point voltage are updated in real time. Further, the working status of the power supply system can be fed back in real time, so that the photovoltaic system can predict the capacity of an energy storage apparatus or regulate charging and discharging of the energy storage apparatus. After a curtailment state ends, the photovoltaic system is relatively quickly restored to the normal working state, so that a loss of generated power is reduced.

Abstract: An internal voltage generator of a smart card and a smart card including the same. The internal voltage generator may include: a mode detector that generates a mode signal indicating a contact mode or a contactless mode; a low-drop out (LDO) regulator including an error amplifier, where the LDO regulator is responsive to the mode signal to: in the contact mode, drive the error amplifier with a second driving voltage to generate an error voltage, and regulate the second driving voltage based on the error voltage to generate a first output voltage, and in the contactless mode, drive the error amplifier with the first driving voltage to generate the error voltage, and regulate the second driving voltage based on the error voltage to generate the first output voltage.

Abstract: A physical address determining method, apparatus, and device, and a storage medium, and belongs to the field of solar power generation, includes: controlling at least two slave nodes to sequentially start up, and detecting a change status of an input voltage of the master node; dividing a photovoltaic power generation system into a plurality of photovoltaic strings; and for each candidate photovoltaic string, controlling any slave node located in the candidate photovoltaic string to start up and other slave nodes to shut down, and using the physical address as a physical address of the candidate photovoltaic string. This disclosure provides a manner of automatically determining a physical address of a photovoltaic string, thereby implementing photovoltaic-string locating and expanding a system function range. When an anomaly occurs, the anomaly can be eliminated in a timely manner, thereby improving system stability.

Abstract: A momentary circuit interrupter in series connection with a mechanical switch to provide protection against short circuit faults in a DC power circuit. The momentary circuit interrupter injects a transient voltage pulse via a pulse transformer to reduce a DC fault current to near zero in a DC circuit branch, thus allowing the mechanical switch to disconnect the faulty branch under a near zero-current condition. The power electronic circuit on the primary side of the transformer controls the discharge of a plurality of pre-charged capacitors to generate the transient voltage pulse during the fault interruption process, but otherwise does not incur any power loss during normal operation. The secondary winding of the pulse transformer conducts the main DC current, and is highly conductive to minimize the conduction power loss.

Abstract: Battery management circuits include a first charging channel, a Cuk circuit, and a communication control circuit. A battery is charged through the first charging channel based on charging voltage and/or charging current provided by a power supply device. The battery includes a first cell and a second cell coupled in series. The communication control circuit is configured to communicate with the power supply device, to make magnitude of the charging voltage and/or charging current provided by the power supply device match a present charging stage of the battery, and the communication control circuit is further configured to send a drive signal to the Cuk circuit to drive the Cuk circuit to work, to make energy of the first cell and the second cell be transferred through the Cuk circuit to balance voltage of the first cell and voltage of the second cell.

Abstract: The disclosure discloses a photovoltaic power optimization system, comprising: a plurality of photovoltaic panels; a photovoltaic optimizing module array comprising a plurality of photovoltaic optimizing modules connected in series, each of the photovoltaic optimizing modules being electrically connected to at least one of the photovoltaic panels; an inverter electrically connected to an output terminals of the photovoltaic optimizing module array for converting a DC power into an AC power; and a data center unit communicates wirelessly with at least one of the photovoltaic optimizing modules, and also communicates with the inverter via power line.

Abstract: Embodiments relate to the field of photoelectric technologies, and provide a method for controlling photovoltaic power generation, a control device, and a photovoltaic power generation system. The method is applied to the photovoltaic power generation system. The system includes at least one photovoltaic string and a control device, the photovoltaic string includes at least one photovoltaic module, each photovoltaic module includes a photovoltaic unit and an optimizer that is connected to the photovoltaic unit, and the photovoltaic unit includes at least one photovoltaic component. The method includes: periodically sending, by the control device, an output voltage reference value update instruction to an optimizer in each photovoltaic string; and receiving, by the optimizer in each photovoltaic string, the output voltage reference value update instruction, and updating an output voltage reference value according to the output voltage reference value update instruction.

Abstract: Electrified vehicle electrical systems and formatting methods include arranging a first layer including one or more first electrical transmission lines each configured to carry electrical power at a first voltage to one or more electrical powertrain components of the electrified vehicle, arranging a second layer above at least a portion of the first electrical connection layer, wherein the second layer includes one or more second electrical transmission lines each configured to carry electrical power at a second voltage to one or more electrical power distribution components of the electrified vehicle, and arranging a third layer above at least a portion of the first and second layers, wherein the third layer includes one or more third electrical transmission lines each configured to carry electrical power at a third voltage to one or more input/output device components of the electrified vehicle.

Abstract: A power system comprising one or more power generators and a combiner. The system may be electrically connected to or include one or more loads. The combiner may have input terminals that are coupled to outputs of the power generators. The combiner may also have output terminals that are coupled to input(s) of the one or more loads. The power generators may be configured to transfer harvested power to the combiner, and the combiner may be configured to transfer the harvested power to the one or more loads.

Abstract: A DC power supply system includes: a DC bus serving as a bus bar for DC power supply; a natural energy power generator 30 that supplies generated power to the DC bus; a plurality of storage batteries that store the generated power from the natural energy power generator; a plurality of bidirectional DC-DC converters that connect the plurality of corresponding storage batteries to the DC bus; a power management apparatus that manages operations of the plurality of bidirectional DC-DC converters; and a target voltage corrector that calculates a correction value of a target value for the output voltage by using an average value of a plurality of actual measurement values of each output voltage of the bidirectional DC-DC converters. The power management apparatus individually controls the each output voltage of the bidirectional DC-DC converters by using each target value of the output voltages corrected based on the correction value.

Abstract: An integrated communication power system supplies power to a communication equipment, and the communication equipment includes a base station module and an antenna processing module. The integrated communication power system includes a first transfer switch, a first integrated conversion module, a DC conversion module, and an energy storage module. The first transfer switch selectively switches one of input sources and a renewable energy to be coupled to the first integrated conversion module to receive an input voltage. The first integrated conversion module converts the input voltage into a DC voltage, and the DC conversion module provides an output voltage to supply power to the antenna processing module according to the DC voltage. The energy storage module receives an energy storage voltage provided by the first integrated conversion module or the DC conversion module to supply power to the base station module.

Abstract: A switched capacitor (SC) power stage includes a first stage circuit with a set of switches coupled in series, a first flying capacitor coupled to a first node between a first and second switch and to a second node between a fifth and sixth switch, a second flying capacitor coupled to a third node between the second and a third switch and to a fourth node between a seventh and eighth switch, and a third flying capacitor coupled to a fifth node between a third and fourth switch and a second terminal coupled to the second node. A control circuit establishes a first configuration of the switches to precharge the first, second, and third flying capacitors to a first voltage, and a second configuration of the switches to precharge the first and second flying capacitors to a second voltage while the third flying capacitor remains charged at the first voltage.

Abstract: Provided is a method of controlling wind turbine converters of wind turbines parallel connected at a point of common coupling, the method including: generating for each converter within a same length of a pulse width modulation period a pulse, wherein the pulses start for different converters at different pulse start phases, wherein pulse start phase differences of the pulse start phases between at least two of adjacent converters are unequal.

Abstract: A master converter and a plurality of slave converters each have an input connected to an associated one of a plurality of power storage elements, respectively, and an output connected to an output terminal in parallel. The master converter converts the voltage of the associated capacitor based on a duty ratio for matching an output voltage to a voltage command value, outputs the converted voltage to the output terminal, and transmits a control signal indicative of the duty ratio to the plurality of slave converters via a signal insulation unit. Each of the plurality of slave converters converts the voltage of the associated capacitor in response to the control signal transmitted via the signal insulation unit and outputs the converted voltage to the output terminal. A correction means is configured to correct at least the duty ratio in the master converter such that the duty ratio in the master converter matches the duty ratio in each of the plurality of slave converters.

Abstract: A modular power supply system includes: a main controller, configured to output a main control signal; N local controllers, wherein each of the local controllers is configured to receive the main control signal to output at least one local control signal; and N power units, in one-to-one correspondence with the N local controllers, wherein each of the power units includes a first end and a second end, and the second end of each of the power units is connected to the first end of an adjacent one of the power units, each of the power units is configured to include M power converters, each of the power converters is configured to operate according to the local control signal, wherein the same local control signal controls the power semiconductor switches at an identical position in at least two of the M power converters to be simultaneously turned on and off.

Abstract: Implementations described and claimed herein provide systems and methods for supplying voltage to a load and battery. In one implementation, a first regulated DC-to-DC converter is electrically connected to a first energy source to down convert a first voltage supplied by the first energy source. A load is electrically connected to the first regulated DC-to-DC converter to receive the down converted first voltage. A second regulated DC-to-DC converter is electrically connected to the first regulated DC-to-DC converter to regulate the down converted first voltage to a second voltage. A second power source is electrically connected to the second regulated DC-to-DC converter to charge the second power source using the second voltage, and the second power source is switchably connectable to the load.

Abstract: Disclosed is a solid-state transformer having an uninterrupted operation ability under an AC/DC fault, in which bridge arms of a hybrid modular multilevel converter include half-bridge submodules and full-bridge submodules. The half-bridge submodules and the full-bridge submodules are connected with input ends of isolated dual-active-bridge converters via DC capacitors of the half-bridge submodules and full-bridge submodules; output ends of the isolated dual-active-bridge converters are connected in parallel to form a low-voltage DC bus; and a three-phase full-bridge inverter is connected to the low-voltage DC bus. The solid-state transformer may be provided with four ports including a medium-voltage AC port, a medium-voltage DC port, a low-voltage DC port and a low-voltage AC port which are beneficial to the interconnection of multi-voltage-level and multi-form AC/DC hybrid distribution grids. The solid-state transformer has the uninterrupted operation ability under the AC/DC fault.

Abstract: A multi-frequency uniformization carrier wave slope random distribution pulse width modulation method, includes: (1) selecting a required random carrier wave sequence and a modulating wave, and after the two are compared, generating a switch device drive signal for pulse width modulation; (2) determining a multiple n of an equivalent carrier frequency f of the random carrier wave sequence, and selecting a main circuit topology; and (3) inputting the switch device drive signal generated in (1) into the main circuit topology of (2) to perform multi-frequency uniformization carrier wave slope random distribution pulse width modulation. The disclosure can improve a frequency domain distribution bandwidth of a harmonic wave without changing the mean and variance of a random carrier wave sequence, and realizes uniform distribution of carrier waves and multiple harmonic peaks near a doubled frequency of the carrier waves in a wider frequency domain.

Abstract: The inventive technology, in certain embodiments, may be generally described as a solar power generation system with a converter, which may potentially include two or more sub-converters, established intermediately of one or more strings of solar panels. Particular embodiments may involve sweet spot operation in order to achieve improvements in efficiency, and bucking of open circuit voltages by the converter in order that more panels may be placed on an individual string or substring, reducing the number of strings required for a given design, and achieving overall system and array manufacture savings.

Abstract: A direct current-to-direct current (DC-DC) converter providing multiple operation modes includes a buck power stage configured to lower an input voltage, a boost power stage configured to increase the input voltage, and a multi-mode controller configured to control the buck power stage and the boost power stage, wherein the multi-mode controller is configured to generate a signal to control the buck power stage and the boost power stage according to the input voltage and an output voltage, and control the buck power stage and the boost power stage using the signal.

Abstract: A power conversion system is to be used with an energy source. A plurality of conversion units are used in series via their output with the energy source output. A positive pin of a first converter and the negative pin of a last converter of the series are for connection to an output (14, 16) of the energy source, and for each two neighboring converters in this series a negative pin of an upstream converter is connected to a positive pin of a downstream converter which both pins are decoupled from the energy source except for the positive pin of the first converter and the negative pin of the last converter. A master monitor unit is adapted to monitor the output power of the energy source and to control the input voltage of each conversion unit synchronously in dependence on the monitored output power. In this way, a set of conversion units are configured, with the conversion units sharing the output from the energy source. This provides a scalable system.

Abstract: Aspects of the present disclosure provide for a method. In at least some examples, the method includes controlling gate terminals of one or more transistors of a charger to operate the charger in a buck-boost mode of operation to generate a system voltage based on a bus voltage by performing power conversion through switching, determining that the bus voltage is greater in value than a voltage of a battery coupled to the charger, and controlling the gate terminals of the one or more transistors of the charger to operate the charger in a pass-through mode of operation to generate the system voltage based on the bus voltage without performing power conversion.

Abstract: A physical address determining method, apparatus, and device, and a storage medium, and belongs to the field of solar power generation, includes: controlling at least two slave nodes to sequentially start up, and detecting a change status of an input voltage of the master node; dividing a photovoltaic power generation system into a plurality of photovoltaic strings; and for each candidate photovoltaic string, controlling any slave node located in the candidate photovoltaic string to start up and other slave nodes to shut down, and using the physical address as a physical address of the candidate photovoltaic string. This disclosure provides a manner of automatically determining a physical address of a photovoltaic string, thereby implementing photovoltaic-string locating and expanding a system function range. When an anomaly occurs, the anomaly can be eliminated in a timely manner, thereby improving system stability.

Abstract: An electric power system is disclosed herein. The electric power system may manage and store electric power and provide uninterrupted electric power, derived from a plurality of electric power sources, to an electric load. The electric power system may contain an energy storage unit and generator assembly. The electric power system may connect to a power grid and renewable energy sources, and may charge the energy storage unit using the power grid, renewable energy sources, and/or generator assembly. The electric power system may be configured to determine load power usage and environmental factors to automatically and continuously modify a charging protocol to, for example, provide high efficiency and/or self-sufficiency from the power grid. The electric power system may operate entirely off-grid and may provide electricity to the load without interruption to power.

Abstract: A power conversion system according to the present disclosure includes a plurality of power converters for performing power conversion on AC power and is connected to a power grid of multi-phase power that is a combination of multiple alternating current sources with mutually different phases. Each of the plurality of power converters includes a power converter circuit, a setting unit, and a control circuit. The power converter circuit performs power conversion between either DC power or AC power and AC power supplied from any of the multiple alternating current sources. The setting unit selects one of the multiple alternating current sources as a target of the power conversion to be performed by the power converter circuit. The control circuit controls operation of the power converter circuit in accordance with selection made by the setting unit.

Abstract: Disclosed is a drive system and its operation for multiple DC-AC inverters working in parallel, for applications such as off-grid solar energy harvesting, which enables a stable operation under various load conditions. The disclosed drive system offers voltage and frequency synchronized sine wave output from each of the inverters, enabling stable operation of the entire system under differing load conditions.

Abstract: The invention relates to a grid synchroniser for connecting an AC output of a power converter to the AC grid mains. In one aspect the invention provides a grid synchroniser comprising an inverter controller to control an AC output of the inverter, the controller including a receiver to receive grid data from a grid sensor location remote from said inverter. In another aspect we describe techniques for rapid removal of charge from a control terminal of a power switching device such as a MOSFET, IGBT or Thyristor using a particular driver circuit.

Abstract: A device for preparing a high-voltage direct current transmission includes a first busbar which is connectable to a plurality of first energy generation or consumer units and a second busbar which is connectable to a plurality of second energy generation or consumer units. A transformer system includes a first primary coil which is connectable to the first busbar, a second primary coil which is connectable to the second busbar, and a secondary coil system which is inductively coupled to the first primary coil and the second primary coil to transform power routed on the first and second busbars to increased AC voltage. A converter system is connected to the secondary coil system to convert the increased AC voltage into DC voltage for the high-voltage direct current transmission. A converter station and an energy providing system are also provided.

Abstract: A control device for controlling a power source connected to an alternating-current (AC) power system includes: a frequency control unit that controls a frequency of the power source operating in a constant-voltage constant-frequency control scheme; a power calculation unit that calculates, when the frequency control unit varies a frequency of the power source, a variation of an effective power output from the power source; an arithmetic unit that calculates a frequency characteristics constant of the AC power system, based on a variation of the frequency of the power source and the variation of the effective power output from the power source; and a selection unit that selects a control scheme for the power source, based on the frequency characteristics constant of the AC power system.

Abstract: A method for testing a photovoltaic panel connected to an electronic module. The electronic module includes an input attached to the photovoltaic panel and a power output. The method activates a bypass to the electronic module. The bypass provides a low impedance path between the input and the output of the electronic module. A current is injected into the electronic module thereby compensating for the presence of the electronic module during the testing. The current may be previously determined by measuring a circuit parameter of the electronic module. The circuit parameter may be impedance, inductance, resistance or capacitance.

Abstract: A two-phase boost converter is provided. The converter includes a first boost converter coupled between an input node and a common node; and a second boost converter coupled between the input node and an output node, wherein the second boost converter comprises: a first transistor coupled between ground and an internal node, an inductor coupled between the input node and the internal node, a capacitor coupled between the internal node and the common node, and a second transistor coupled between the common node and the output node.

Abstract: Apparatus and method for controlling reactive power. In one embodiment, the apparatus comprises a bidirectional power converter comprising a switched mode cycloconverter for generating AC power having a desired amount of a reactive power component.

Abstract: If current path is switched via switching, voltage overshoot exceeding the device breakdown voltage may be generated. A flying capacitor circuit is provided, having a plurality of switching devices cascade-connected on a first surface of a substrate; a plurality of rectifier devices cascade-connected on a second surface of the substrate; and at least one capacitor provided in a wiring connecting main terminals of a switching device and a rectifier device that are associated with each other and included in the plurality of switching devices and the plurality of rectifier devices; and at least part of the wiring runs sandwiching the substrate in parallel.

Abstract: When the AC voltage effective value at an interconnection point is higher than a first threshold voltage, a solar-panel power conversion device controls an output of reactive power so that the voltage at the interconnection point matches a first target effective voltage. When the power generated from an energy creation apparatus is higher than a first reference power and the AC voltage effective value at the interconnection point is higher than a second threshold voltage, then a storage-battery power conversion device controls an output of reactive power so that the voltage at the interconnection point matches a second target effective voltage.

Abstract: A photovoltaic power plant system for power generation, comprising one or more photovoltaic clusters and one or more modular multilevel converters. Each photovoltaic cluster includes a number of photovoltaic strings connected to one or more MPPT DC/DC, converters connected to a common LVDC, bus. Each photovoltaic cluster includes a DC/DC converter including an input connected to the LVDC bus, and an output connected to a MVDC collection grid. Each of the one or more modular multilevel converters includes an input connected to the one or more photovoltaic clusters via the MVDC collection grid and an output connected to a transmission grid.

Abstract: One aspect of the present invention is an electric power transmission device that periodically shifts a frequency of a magnetic field to a plurality of predetermined shift values and that transmits electric power by utilizing the magnetic field. The device includes a plurality of power transmitters and an instructor. Each of the plurality of power transmitters configured to generate a magnetic field. The instructor outputs an instruction signal indicating a shift value to be shifted to each of the power transmitters to instruct the shift value to be shifted to each of the power transmitters. Further, the instructor instructs the shift value to be shifted in such a manner that at least a part of the magnetic fields of the plurality of power transmitters are different in frequency at the same time point.

Abstract: A traction voltage system in a vehicle includes a junction box with multiple connectors for electrical components, which components include electrical supplies and electrical loads, and an electronic control unit arranged to monitor current flowing flow to or from the components. A controller or a circuit breaker is arranged to control the supply of power to each respective component, and at least all but one of the connectors are provided with a current sensor arranged to transmit a signal representing detected current values to the electronic control unit. The electronic control unit is arranged to determine an instantaneous current value flowing to or from each component, to compare the instantaneous current value with a predetermined limit value for each connector, and to take action in response to the comparison. A method for controlling the traction voltage system is also provided.

Abstract: A configuration with which, even if the supply of power from a power supply portion ceases, the power from another power supply source can be instantly supplied to a power supply target is more easily achieved. In a backup circuit, a control unit causes a second voltage conversion portion to perform a voltage conversion operation in response to satisfaction of a predetermined first backup condition, and a power supply portion-side conductive path and an electricity storage portion-side conductive path are electrically connected to each other via a resistive portion when the control unit is causing the second voltage conversion portion to perform the voltage conversion operation. Furthermore, the control unit causes the first voltage conversion portion to perform a second operation in response to a predetermined second backup condition being satisfied when the control unit is causing the second voltage conversion portion to perform the voltage conversion operation.