Abstract: A UPS system includes UPS devices and a common bus. The UPS devices are configured to output respective backup voltages. The common bus electrically interconnects the UPS devices for receiving the backup voltages, and is configured to output to the UPS devices a greatest one of the backup voltages as a dominant voltage. Each UPS device is operable to detect the backup voltage outputted thereby, to compare the backup voltage with the dominant voltage, to determine whether a power recovery signal is received from the power supply equipment, and to vary the backup voltage with a descending trend, where the varying of the backup voltage is conducted at least based on the dominant voltage and the backup voltage.

Abstract: A power transmitter for transferring power to a power receiver using a wireless inductive power signal includes a power source provides a power source signal which may have level variations. A power signal generator generates a drive signal from the power source signal by a frequency converter which increases the frequency of the drive signal relative to the power source signal. A limiter restricts the power of the drive signal fed to the inductor to be below a threshold in repeating time intervals. A synchronizer synchronizes the repeating time intervals to the power source signal. In the power receiver, an inductor receives a power signal from the power transmitter, a load coupler decouples the power load from the inductor during the repeating time intervals and a synchronizer synchronizes the repeating time intervals of the receiver to the power signal. Communication units exchange data during the repeating time intervals.

Abstract: A power supply system includes a power conversion circuit, a conversion control circuit, an auxiliary power module, an electricity supply module and a power supply control circuit. The power conversion circuit converts an input power into an output power used as an output of the power supply system. The conversion control circuit is arranged for controlling an operation of the power conversion circuit according to a control power. The auxiliary power module is arranged for selectively outputting a first electrical power to the conversion control circuit. The electricity supply module is arranged for providing a second electrical power. The power supply control circuit is coupled to the auxiliary power module and the electricity supply module, and arranged for referring to at least the second electrical power to determine whether to provide the first electrical power or the second electrical power as the control power for the conversion control circuit.

Abstract: A method for detecting and preventing islanding includes issuing a command to an inverter connected to a power source, where the inverter is coupled to a power grid and supplies power to the power grid, the command causes a frequency of a waveform output by the inverter to vary, and the frequency of the waveform output by the inverter is a command frequency, determining that a amount of change of the command frequency is a constant value for a predetermined amount of time, removing the power supplied by the inverter from the power grid, and determining whether the power grid is valid.

Abstract: A circuit arrangement can be used for adapting the electroacoustic properties of an electroacoustic component. The circuit arrangement includes a first conductor loop and a further element. The first conductor loop includes a main loop and a negative feedback loop. The negative feedback loop has a sense of curvature that is opposite to a sense of curvature of the main loop. The negative feedback loop compensates for a coupling between the main loop and the further element.

Abstract: Disclosed are a wireless power transmitter and a power transmission method thereof. The wireless power transmitter includes a plurality of transmission resonance units, a detection power applying unit applying detection power to the transmission resonance units to detect a location of the wireless power receiver, and a current measuring unit measuring current generating from a transmission coil unit of the wireless power transmitter based on the applied detection power. The wireless power transmitter transmits the power through at least one transmitting resonance unit corresponding to the location of the wireless power receiver based on the measured current.

Abstract: A power supply ECU executes turn-on current control for controlling a turn-on current It to a target value Itr by adjusting a drive frequency f, turn-on current It indicating an output current Io of an inverter at a rising of an output voltage Vo of the inverter. Target value Itr is set to fall within a range where a recovery current is not produced in the inverter. In the turn-on current control, when a startup frequency indicating drive frequency f at a startup of the inverter is fa0, the control unit adjusts drive frequency f to be more than or equal to fa0. When turn-on current It is larger than target value Itr, the control unit adjusts drive frequency f in the direction toward startup frequency fa0.

Abstract: Various examples are directed to systems and methods for detecting an islanding condition at an inverter configured to couple a distributed generation system to an electrical grid network. A controller may determine a command frequency and a command frequency variation. The controller may determine that the command frequency variation indicates a potential islanding condition and send to the inverter an instruction to disconnect the distributed generation system from the electrical grid network. When the distributed generation system is disconnected from the electrical grid network, the controller may determine whether the grid network is valid.

Abstract: A method provides power to a subsea equipment electrical system underwater, without a wet-mated electrical connection. The method includes temporarily coupling a rotary coupling element of a power source to the subsea equipment and turning that element to generate electric power on board the equipment. Subsea equipment that implements the method comprises: an on-board electric power generator connected to an electrical load such as a rechargeable battery to charge the battery when the generator is driven; and a rotary coupling element that is turned by an external drive to drive the generator. Alternative subsea equipment to implement the method comprises: a stator, but not a rotor, of an on-board electric power generator, which supplies current to the load when an externally-driven rotor is positioned adjacent to the stator and turned relative to the stator. A power source having a generator rotor is docked with the equipment for this purpose.

Abstract: A vehicular system mounted to a vehicle includes: a power-feeding device that wirelessly feeds power to a power-feeding object device; a communication device that performs wireless communication with a predetermined portable device; and a control device that controls to stop a power-feeding operation of the power-feeding device when the communication device performs wireless communication with the portable device.

Abstract: A rectifier includes a first diode, a second diode, a first switch and a second switch. Each of the first switch and the second switch includes a controlling pole, a first connecting pole and a second connecting pole. A positive pole of the first diode, the second connecting pole of the first switch, and the controlling pole of the second switch are coupled to a first pole of an alternating current (AC) power. A positive pole of the second diode, the second connecting pole of the second switch, and the controlling pole of the first switch are coupled to a second pole of the AC power. A negative pole of the first diode and a negative pole of the second pole are coupled to an output pole, and the first connecting pole of the first switch and the first connecting pole of the second switch are grounded.

Abstract: A foreign object detector includes a plurality of first coils and a plurality of second coils. The plurality of first coils are arranged along an upper surface of a power transmission coil. The plurality of second coils are provided to correspond to the plurality of first coils, with the second coils each being arranged to face a corresponding one of the first coils. An outer shape of each of the plurality of first coils and each of the plurality of second coils is smaller than an outer shape of the power transmission coil when the power transmission coil is viewed two-dimensionally from above the power transmission coil.

Abstract: A resonant contactless electric energy transmitter configured to contactlessly supply electric energy to an electric energy receiver, can include: (i) a high frequency power supply configured to generate a high frequency AC power with a frequency that is the same as a leakage inductance resonant frequency, where the leakage inductance resonant frequency is obtained by detection of an output current of the high frequency power supply that corresponds to the high frequency AC power of a sequence of different frequencies during a frequency sweeping time period; and (ii) a transmitting resonant circuit comprising a transmitting coil, and being configured to receive the high frequency AC power from the high frequency power supply.

Abstract: A multi-functional automatic switching circuit for direct current ice melting and a switching method thereof are provided. The automatic switching circuit comprises at least one sub-switching circuit. The sub-switching circuit comprises a six-pulse current converter (R) with no saturable reactor, six reactors (L1a, L1b, L1c, L2a, L2b, and L2c), three three-phase knife switches (Sac1, Sac2, and Sac3), and five single-phase knife switches (SV1, SV2, SV3, SV4, and SV5). The sub-switching circuits in series connection or parallel connection, four direct current side switching knife switches (Sdc1, Sdc2, Sdc3, and Sdc4), an isolation knife switch (K), a breaker (QF) and a control and protection system (CP) may form an automatic switching circuit for six-pulse or twelve-pulse direct current ice melting.

Abstract: A method for controlling a power switching apparatus to solve problems including: setting a target time reaching a predetermined position immediately before a target phase by a time calculator during an opening and closing operation of a movable arc contact with respect to a fixed arc contact in a target phase at a predetermined average switching speed; and controlling an electric motor at a speed equal to or less than an average switching speed immediately before the target phase from an operation start time to the target time by a motor controller.

Abstract: A power supply system includes a plurality of electrical storage devices, a distributor configured to distribute electric power between the plurality of electrical storage devices in a desired distribution mode, and an electronic control unit. The electronic control unit configured to (i) set the desired distribution mode based on at least one of a magnitude relation between first rates of change in dischargeable power of the corresponding electrical storage device to a charge state value indicating a remaining level of charge of the corresponding electrical storage device, or a magnitude relation between second rates of change in chargeable power of the corresponding electrical storage device to the charge state value, and (ii) control the distributor such that electric power is distributed in the set distribution mode.

Abstract: A voltage measuring method for a supplying-end module of an induction type power supply system includes generating a coil signal on a supplying-end coil of the supplying-end module; clamping the coil signal to generate a clamp coil signal; performing signal processing on the clamp coil signal to generate a first signal and a second signal, respectively; generating a cyclic signal, a frequency of which is equal to a frequency of the coil signal; comparing the first signal and the second signal via a comparator to obtain a first time and a second time when the first signal and the second signal have an equal voltage level during a cycle of the cyclic signal; calculating a middle time of the first time and the second time; and sampling the clamp coil signal or the coil signal to obtain a peak voltage of the coil signal according to the middle time.

Abstract: A power supply circuit coupled to a power source for providing electronic energy to a workload includes a first switch, a control circuit, a first diode, and a backup power, in which the input of the first switch is coupled to the power source, the output of the first switch is coupled to the workload, the control circuit is coupled to the control terminal of the first switch for determining the state of the power source, the anode of the first diode is coupled to the power source, the cathode of the first diode is coupled to the first terminal of the backup power, the first terminal of the backup power is further coupled to the workload, when the control circuit determines that the power source is in a power-off state, a control signal is applied to the control terminal of the first switch to turn off the first switch.

Abstract: Relays having internal connections on both sides of their switches may be used in conjunction with a connector that integrates both the normal relay switch control lines with the sensing conductors of a control module for a battery module of an energy storage device. In this manner, sensing conductors may be routed along with the switch control lines for the relay instead of separately as described above. This integration reduces the complexity and cost associated with the energy storage device, because it reduces the number of separately routed lines and also eliminates the external connections for at least some of the sensing conductors.

Abstract: The invention relates to a method and system for controlling an engine (552) in a sweeper-scrubber. An electrical system alternator (554) provides power to at least one cleaning function (576, 578, 580) of a self-propelled hybrid vehicle and to driven wheels. The operational load is monitored, and the running state of an internal combustion engine (552) is controlled based on the monitored operational load. A threshold charge, of an electrical system battery pack (556) is maintained.