A method of providing a single structure multiple mode antenna is described. The antenna is preferably constructed having a first inductor coil that is electrically connected in series with a second inductor coil. The antenna is constructed having a plurality of electrical connections positioned along the first and second inductor coils. A plurality of terminals is connected to the electrical connections that facilitate numerous electrical connections and enables the antenna to be selectively tuned to various frequencies and frequency bands.

The invention relates to a method for power consumption and power input control in an electrical power supply network, wherein a control signal with an item of tariff information is generated by a signal station at a power supply and unidirectionally output via the power supply network, wherein the control signal is received by at least one receiving unit arranged in the power consumption network and the control signal received by the receiving unit is used for operation control of a power output unit/power input unit for a downstream power consumer/power generator. A device for power consumption/power generation control comprises a receiving unit for a control signal transmitted via a power supply network with means for converting the control signal and for generating switching processes for a power output/power input unit controlled by the receiving unit for connecting a downstream consumer/generator.

In the field of high voltage direct current (HVDC) power transmission networks there is a need for an improved power converter. A power converter, for use in a HVDC power transmission network, comprises first and second DC terminals, for connection in use to a DC network and between which extends at least one converter limb. The or each converter limb includes first and second limb portions which are separated by an AC terminal, for connection in use to an AC network. Each limb portion includes a switching valve, and the power converter including a controller programmed to control switching of the switching valves to control the flow of a converter current (I.sub.max) through the power converter and thereby in-use transfer power between the power converter and the AC network. The power transferred between the power converter and the AC network has an active component and a reactive component. The controller is further programmed in use to: (i) prioritize to a first extent the transfer of reactive power between the power converter and the AC network during a first operating condition, when the AC voltage (V) of the AC network lies outside a desired operating range, by allowing up to a first amount of the converter current (I.sub.max) to be a reactive current; and (ii) prioritize to a second extent, less than the first extent, the transfer of reactive power between the power converter and the AC network during a second operating condition, when the AC voltage (V) of the AC network lies within the desired operating range, by limiting the amount of converter current (I.sub.max) that can be a reactive current to a second amount, less than the first amount, the second amount being determined according to a measured operating frequency of the AC network.

Embodiments of this application provide a direct current bus voltage control method and apparatus, and a power system, and relate to the field of electric power technologies, to quickly identify a voltage between an inverter circuit and an alternating current grid, so as to timely control a voltage of a direct current bus, thereby improving stability of the power system. The method includes: obtaining an electrical parameter between the conversion circuit and the direct current bus; generating a predicted voltage between the inverter circuit and the alternating current grid based on the electrical parameter and a voltage prediction model; and controlling a voltage between the conversion circuit and the direct current bus based on the predicted voltage.

A system includes a transformer rectifier unit (TRU) including a backfeed sense module. A contactor is operatively connected to the TRU for selectively supplying DC power to a DC bus from the TRU with the contactor closed and isolating the DC bus from the TRU with the contactor opened. A contactor driver is operatively connected to receive a signal from the backfeed sense module and to control opening and closing of the contactor based on the signal. The contactor driver is configured to open the contactor upon receipt of the signal indicative of backfeed detected in the TRU.

Multi-port power adapters. At least one example is a method including: supplying a first bus voltage to a first device by way of a DC-DC converter coupled to a link voltage; supplying a second bus voltage to a second device by way of a second DC-DC converter coupled to the link voltage; converting an AC voltage to the link voltage by way of an AC-DC converter; selecting, by a shunt regulator, a setpoint for the link voltage based on the first bus voltage and the second bus voltage; and regulating the link voltage to the setpoint by the AC-DC converter.

A power supply circuit for an x-ray production system, which has an inverter circuit with an output for connecting the inverter circuit with an x-ray source of the x-ray production system, includes a rectifier circuit including an input to connect the rectifier circuit with a power supply network, the rectifier circuit further including an output to connect to an input of the inverter circuit; and a backup circuit including a plurality of electrical energy storage cells, the plurality of electrical energy storage cells being connectable in series between the input of the inverter circuit and the output of the rectifier circuit.

A system is described that turns off a high power, power supply when a device no longer needs high power. A low power, power supply or a rechargeable battery provides power to determine when the device again needs high power. The low power supply consumes a minimum possible power when the device does not need high power and the power rechargeable battery is not charged. That is, the high power and low power, power supplies are turned on or off based on the real time power consumption need of the device and the charged state of the battery. The power need of the device is monitored by a current shunt monitoring circuit and a control signal monitoring circuit.

A system is described that turns off a high power, power supply when a device no longer needs high power. A low power, power supply or a rechargeable battery provides power to determine when the device again needs high power. The low power supply consumes a minimum possible power when the device does not need high power and the power rechargeable battery is not charged. That is, the high power and low power, power supplies are turned on or off based on the real time power consumption need of the device and the charged state of the battery. The power need of the device is monitored by a current shunt monitoring circuit and a control signal monitoring circuit.

A method for dispatching an operation of a distribution feeder of electrical power into a grid with heterogeneous prosumers, the method comprising the steps of establishing a dispatch plan on a computer by using forecast data of an aggregated consumption and local distributed generation at the grid for a predetermined period, and operating the distribution feeder according to the established dispatch plan during the predetermined period.