Abstract: A power supply system includes an input terminal receiving an alternating current input; an output terminal connected to a load; a first switch, a second switch and a third switch; a rectification and charging-discharging module with one end coupled to the input terminal through the first switch and coupled to a battery through the third switch; a conversion module with one end coupled to the other end of the rectification and charging-discharging module via a direct current bus, and the other end coupled to the output terminal; and a bypass module with one end coupled to the input terminal, and the other end coupled to the output terminal through the second switch.

Abstract: A two-start helical heat exchanger comprises a helical baffle extending along a length of the heat exchanger and having first and second surfaces, wherein: the first surface of the baffle is arranged to provide a first helical fluid flow path for a first fluid; and the second surface of the baffle is arranged to provide a second helical fluid flow path for a second fluid, wherein the second fluid flow path is arranged in counter-flow with the first fluid flow path and a casing within which the baffle is mounted. The baffle is arranged such that first and second fluid flow paths are in thermal contact with each other through the baffle, and in thermal contact with the casing. The heat exchanger may be incorporated into a power converter, for example to cool the power converter. The heat exchanger may be used on an aircraft.

Abstract: The present disclosure concerns a current limiting circuit for a power converter, which may be used to limit charge and discharge currents for electrical power storage units. In an example embodiment, a current limiting circuit comprises: first and second field effect transistors, each having source, gate and drain connections, wherein the source connection of the first transistor is connected to the gate connection of the second transistor and the source connection of the second transistor is connected to the gate connection of the first transistor; and a resistor connected between the source connections of the first and second transistors, wherein drain connections of the first and second transistors are connectable between a DC electrical power supply and an electrical load for limiting a maximum current flowing between the electrical power supply and the electrical load.

Abstract: There is described a device for controlling an amount of current within a power distribution network by manipulating the amount of magnetic flux in the device and thus the impedance experienced by the power distribution network across the device. This is achieved by winding a plurality of coils about a magnetically permeable core and by providing the device with a magnetically permeable bridge element that is movable between a fully-open position at which the net magnetic flux generated in the core by alternating currents in each coil is zero, and a fully-closed position at which a net magnetic flux is present in the core.

Abstract: A two-start helical heat exchanger comprises a helical baffle extending along a length of the heat exchanger and having first and second surfaces, wherein: the first surface of the baffle is arranged to provide a first helical fluid flow path for a first fluid; and the second surface of the baffle is arranged to provide a second helical fluid flow path for a second fluid, wherein the second fluid flow path is arranged in counter-flow with the first fluid flow path and a casing within which the baffle is mounted. The baffle is arranged such that first and second fluid flow paths are in thermal contact with each other through the baffle, and in thermal contact with the casing. The heat exchanger may be incorporated into a power converter, for example to cool the power converter. The heat exchanger may be used on an aircraft.

Abstract: A thermal management device for dissipating heat from one or more electrical components in an aircraft, the thermal management device including: a heat spreader with a plurality of layers of annealed pyrolytic graphite, the heat spreader having higher thermal conductivity in a plane defined by the layers than in a direction perpendicular to the layers; a flow path for a cooling fluid defined through the heat spreader, such that at least a portion of the flow path is surrounded by the heat spreader, wherein the flow path is helical, around a central axis extending through the plurality of layers; and a housing encasing the heat spreader, the housing arranged to have one or more electrical components mounted there-on and to form a thermal interface between the heat spreader and one or more electrical components.

Abstract: In some examples, an electrical power system includes a differential bus including a high-side rail and a low-side rail, a power source configured to generate power, and a bulk capacitor coupled between the high-side rail and the low-side rail, the bulk capacitor configured to filter the power generated by the power source. The electrical power system also includes a converter configured to convert the power filtered by the bulk capacitor and a pre-charging circuit comprising one or more switches and a middle capacitor, the pre-charging circuit configured to pre-charge the bulk capacitor.

Abstract: There is described a device for controlling an amount of current within a power distribution network by manipulating the amount of magnetic flux in the device and thus the impedance experienced by the power distribution network across the device. This is achieved by winding a plurality of coils about a magnetically permeable core and by providing the device with a magnetically permeable bridge element that is movable between a fully-open position at which the net magnetic flux generated in the core by alternating currents in each coil is zero, and a fully-closed position at which a net magnetic flux is present in the core.

Abstract: A thermal management device for dissipating heat from one or more electrical components in an aircraft, the thermal management device including: a heat spreader with a plurality of layers of annealed pyrolytic graphite, the heat spreader having higher thermal conductivity in a plane defined by the layers than in a direction perpendicular to the layers; a flow path for a cooling fluid defined through the heat spreader, such that at least a portion of the flow path is surrounded by the heat spreader, wherein the flow path is helical, around a central axis extending through the plurality of layers; and a housing encasing the heat spreader, the housing arranged to have one or more electrical components mounted there-on and to form a thermal interface between the heat spreader and one or more electrical components.