Abstract: A converter (30) comprises first and second DC terminals (32,34) connectable in use to a DC network (40), the converter (30) including a converter limb (36) extending between the DC terminals (32,34), the converter limb (36) including first and second limb portions separated by an AC terminal (38), the AC terminal (38) connectable in use to an AC voltage, each limb portion including at least one director switch (44) connected in series with a waveform synthesizer between the AC terminal (44) and a respective one of the first and second DC terminals (32,34), the waveform synthesizers operable to control the modulation of an AC voltage waveform at the AC terminal (38), each director switch (44) operable to switch the respective waveform synthesizer into and out of circuit between the respective DC terminal (32,34) and the AC terminal (38); and a controller (56) programmed to selectively control the switching of the director switches (44) to switch both of the limb portions into circuit concurrently to form a cu

Abstract: Capacitive energy storage devices (CESDs) are disclosed, along with methods of making and using the CESDs. A CESD includes an array of electrodes with spaces between the electrodes. A dielectric material occupies spaces between the electrodes; regions of the dielectric material located between adjacent electrodes define capacitive elements. The disclosed CESDs are useful as energy storage devices and/or memory storage devices.

Abstract: A circuit for generating electrical energy is disclosed. The circuit uses a pulse generator in combination with a tube having a cavity therein. The tube can have material therein, such as solid material or fluid passing therethrough. A thyristor or other negative resistance is in series with the tube to increase a change of voltage with respect to time. A resultant energy applied to a load is larger than the energy supplied by the pulse generator due to the absorption of external energy by the tube.

Abstract: A circuit for generating electrical energy is disclosed. The circuit uses a pulse generator in combination with a tube having a cavity therein. The tube can have material therein, such as solid material or fluid passing therethrough. A thyristor or other negative resistance is in series with the tube to increase a change of voltage with respect to time. A resultant energy applied to a load is larger than the energy supplied by the pulse generator due to the absorption of external energy by the tube.

Abstract: Capacitive energy storage devices (CESDs) are disclosed, along with methods of making and using the CESDs. A CESD includes an array of electrodes with spaces between the electrodes. A dielectric material occupies spaces between the electrodes; regions of the dielectric material located between adjacent electrodes define capacitive elements. The disclosed CESDs are useful as energy storage devices and/or memory storage devices.

Abstract: An apparatus can comprise a circuit and an electrical element coupled to the circuit. The circuit can include a pulse generator to generate an electrical pulse having a first power and a load. The electrical element can be configured to receive heat that is converted into electrical energy by the circuit to apply a second power, greater than the first power, to the load.

Abstract: A converter (30) comprises first and second DC terminals (32,34) connectable in use to a DC network (40), the converter (30) including a converter limb (36) extending between the DC terminals (32,34), the converter limb (36) including first and second limb portions separated by an AC terminal (38), the AC terminal (38) connectable in use to an AC voltage, each limb portion including at least one director switch (44) connected in series with a waveform synthesizer between the AC terminal (44) and a respective one of the first and second DC terminals (32,34), the waveform synthesizers operable to control the modulation of an AC voltage waveform at the AC terminal (38), each director switch (44) operable to switch the respective waveform synthesizer into and out of circuit between the respective DC terminal (32,34) and the AC terminal (38); and a controller (56) programmed to selectively control the switching of the director switches (44) to switch both of the limb portions into circuit concurrently to form a cu

Abstract: Capacitive energy storage devices (CESDs) are disclosed, along with methods of making and using the CESDs. A CESD includes an array of electrodes with spaces between the electrodes. A dielectric material occupies spaces between the electrodes; regions of the dielectric material located between adjacent electrodes define capacitive elements. The disclosed CESDs are useful as energy storage devices and/or memory storage devices.

Abstract: Fault protection of a voltage source converter is provided. An apparatus has a chain-link circuit in series with a director switch. The chain-link circuit includes cells including an energy storage element and cell switching elements connected with anti-parallel diodes. Each cell switching element has a cell switching element controller. The director switch includes director switch units, each having a director switching element and a director switch unit controller. Each cell switching element controller monitors for a fault current and turns-off its associated cell switching element and reports a fault event to a fault controller. Each director switch unit controller monitors for a fault current and reports a fault event to the fault controller but the director switch unit control keeps its associated director switching element turned-on. The fault controller monitors for reports of fault events to order the cell switching elements of at least some of the cells to turn-off.

Abstract: A wearable heater and/or cooler device can include one or more fluid pumps, one or more conduits, and one or more chambers. The fluid pumps can be configured for generating flow of a fluid and comprise inlets and outlets. The conduits have first end portions and second end portions, and the first end portions of the conduits can be coupled to the outlets of the fluid pumps. The chambers can be coupled to second end portions of the conduits such that the fluid flows from the fluid pumps, through the conduits, and into the chambers. The chambers can be configured to enhance the desired thermal transport characteristics of the fluid for thermal transfer adjacent to a wearer's body.

Abstract: Embodiments for a voltage source converter are disclosed.

Abstract: An apparatus can comprise a circuit and an electrical element coupled to the circuit. The circuit can include a pulse generator to generate an electrical pulse having a first power and a load. The electrical element can be configured to receive heat that is converted into electrical energy by the circuit to apply a second power, greater than the first power, to the load.

Abstract: Capacitive energy storage devices (CESDs) are disclosed, along with methods of making and using the CESDs. A CESD includes an array of electrodes with spaces between the electrodes. A dielectric material occupies spaces between the electrodes; regions of the dielectric material located between adjacent electrodes define capacitive elements. The disclosed CESDs are useful as energy storage devices and/or memory storage devices.

Abstract: Capacitive energy storage devices (CESDs) are disclosed, along with methods of making and using the CESDs. A CESD includes an array of electrodes with spaces between the electrodes. A dielectric material occupies spaces between the electrodes; regions of the dielectric material located between adjacent electrodes define capacitive elements. The disclosed CESDs are useful as energy storage devices and/or memory storage devices.

Abstract: Capacitive energy storage devices (CESDs) are disclosed, along with methods of making and using the CESDs. A CESD includes an array of electrodes with spaces between the electrodes. A dielectric material occupies spaces between the electrodes; regions of the dielectric material located between adjacent electrodes define capacitive elements. The disclosed CESDs are useful as energy storage devices and/or memory storage devices.

Abstract: Capacitive energy storage devices (CESDs) are disclosed, along with methods of making and using the CESDs. A CESD includes an array of electrodes with spaces between the electrodes. A dielectric material occupies spaces between the electrodes; regions of the dielectric material located between adjacent electrodes define capacitive elements. The disclosed CESDs are useful as energy storage devices and/or memory storage devices.

Abstract: Capacitive energy storage devices (CESDs) are disclosed, along with methods of making and using the CESDs. A CESD includes an array of electrodes with spaces between the electrodes. A dielectric material occupies spaces between the electrodes; regions of the dielectric material located between adjacent electrodes define capacitive elements. The disclosed CESDs are useful as energy storage devices and/or memory storage devices.

Abstract: This application describes methods and apparatus for achieving voltage balancing of clamp capacitors of director switch units of a voltage source converter (VSC). An arm or director switch may be formed from a number of director switch units connected in series, each director switch unit having a semiconductor switching element such as an IGBT. Typically a clamp capacitor may be connected across the IGBT. In some arrangements a floating power supply may draw power from the clamp capacitor to provide power for the director switch unit. In the present application the director switch unit is operable in a voltage balancing mode such that the power drawn from the clamp capacitor varies based on the voltage across the clamp capacitor. In this way the power demand for power drawn from the clamp capacitor may have the characteristic of a resistive load.

Abstract: This application relates to methods and apparatus for fault protection in a DC power transmission network or grid that aid in determining the location of a fault in the network. The method involves, in the event of a fault, controlling at least one current limiting element of the network so as to limit a fault current flowing to below a first current level which is within the expected current operating range of the network in normal operation, i.e. a safe level. The fault current is then controlled to maintain a non-zero level of fault current flow and the characteristics of the fault current flow at different parts of the network are determined by fault current detection modules. The location of the fault is then determined based on the determined characteristics.

Abstract: An apparatus can comprise a DC power supply to generate a DC electrical signal, a pulse generator to generate an electrical pulse, and an electrical element. The pulse generator and the DC power supply can be electrically coupled together. The electrical element can receive the DC electrical signal and the electrical pulse. The electrical element can generate a magnetic field in response to receiving the DC electrical signal and cool in response to receiving the electrical pulse.