Abstract: A hybrid electrical and mechanical ship propulsion and electric power system, includes a first mechanical power plant configured to drive a first propeller via a first shaft. There is a second electrical power plant configured to drive a second propeller via a second shaft. The second electrical power plant includes HTS generators and a high temperature superconductor (HTS) motor interconnected to the second shaft. There is a first electrical network to which the HTS motor is connected in order to energize the HTS motor to drive the second propeller via the second shaft.

Abstract: A hybrid electrical and mechanical ship propulsion and electric power system, includes a first mechanical power plant configured to drive a first propeller via a first shaft. There is a second electrical power plant configured to drive a second propeller via a second shaft. The second electrical power plant includes HTS generators and a high temperature superconductor (HTS) motor interconnected to the second shaft. There is a first electrical network to which the HTS motor is connected in order to energize the HTS motor to drive the second propeller via the second shaft.

Abstract: A static synchronous compensator configured to be installed in and provide reactive power to a medium voltage electric distribution system. There is a multi-level cascaded H-bridge (CHB) converter in an enclosure, having a nominal operating voltage in the medium voltage range. There is a first electrical bushing connecting the medium voltage electric distribution system to the input of the CHB converter. There is a second electrical bushing connecting ground or floating ground to the output of the CHB converter. There is a cooling system, which circulates the cooling fluid between in the interior of the enclosure to cool the CHB converter. There is a controller to control the converter to output reactive power at a medium voltage level.

Abstract: A static synchronous compensator configured to be installed in and provide reactive power to a medium voltage electric distribution system. There is a multi-level cascaded H-bridge (CHB) converter in an enclosure, having a nominal operating voltage in the medium voltage range. There is a first electrical bushing connecting the medium voltage electric distribution system to the input of the CHB converter. There is a second electrical bushing connecting ground or floating ground to the output of the CHB converter. There is a cooling system, which circulates the cooling fluid between in the interior of the enclosure to cool the CHB converter. There is a controller to control the converter to output reactive power at a medium voltage level.

Abstract: An apparatus for harvesting solar power includes a photovoltaic array for generating a DC voltage; a discharge circuit for causing the DC voltage to decay from a first value to a second value; and an inverter circuit for transforming an output voltage from the discharge circuit into an AC voltage.

Abstract: A cryogenically-cooled HTS cable is configured to be included within a utility power grid having a maximum fault current that would occur in the absence of the cryogenically-cooled HTS cable. The cryogenically-cooled HTS cable includes a continuous liquid cryogen coolant path for circulating a liquid cryogen. A continuously flexible arrangement of HTS wires has an impedance characteristic that attenuates the maximum fault current by at least 10%. The continuously flexible arrangement of HTS wires is configured to allow the cryogenically-cooled HTS cable to operate, during the occurrence of a maximum fault condition, with a maximum temperature rise within the HTS wires that is low enough to prevent the formation of gas bubbles within the liquid cryogen.

Abstract: A method of controlling fault currents within a utility power grid is provided. The method may include coupling a superconducting electrical path between a first and a second node within the utility power grid and coupling a non-superconducting electrical path between the first and second nodes within the utility power grid. The superconducting electrical path and the non-superconducting electrical path may be electrically connected in parallel. The superconducting electrical path may have a lower series impedance, when operated below a critical current level, than the non-superconducting electrical path. The superconducting electrical path may have a higher series impedance, when operated at or above the critical current level, than the non-superconductor electrical path.

Abstract: A power electronic assembly includes a pair of thermally and electrically conductive plates, and semiconductor switching elements positioned between contact surfaces of the pair of conductive plates. A first of the semiconductor switching elements is positioned at a first region of the conductive plates, and a second of the semiconductor switching elements positioned at a second region of the conductive plates. At least one of the conductive plates includes an aperture positioned between the first region and the second region of the conductive plates, such that in a compressed state, a contact surface of the conductive plate associated with the first region is substantially parallel to and offset from that of the second region in a direction parallel to the direction of compression.

Abstract: A system for connecting a wind turbine generator to a utility power network includes a first power converter that converts an AC signal from the wind turbine generator to a DC signal and supplies a controlled amount of reactive current to the wind turbine generator. The system also includes a second power converter, connected in series with the first converter, which converts the DC signal from the first power converter to a line-side AC signal and supplies a controlled amount of current to the utility power network. A power dissipation element is coupled to the first and second power converters for dissipating power from the first power converter.

Abstract: In a general aspect, a power conversion system includes a power converter, a transformer, and a voltage adjustment device. The power converter is configured to receive a variable DC power generated by a power generation device and to convert the received DC power to AC power at a first voltage. The transformer is configured to receive the AC power from the power converter and to deliver AC power at a second voltage to a utility power network. The voltage adjustment device is configured to adjust the first voltage to a target value determined on the basis of a voltage of the DC power.

Abstract: In a general aspect, a power conversion system includes a power converter, a transformer, and a voltage adjustment device. The power converter is configured to receive a variable DC power generated by a power generation device and to convert the received DC power to AC power at a first voltage. The transformer is configured to receive the AC power from the power converter and to deliver AC power at a second voltage to a utility power network. The voltage adjustment device is configured to adjust the first voltage to a target value determined on the basis of a voltage of the DC power.

Abstract: A power electronic assembly includes a pair of thermally and electrically conductive plates, and semiconductor switching elements positioned between contact surfaces of the pair of conductive plates. A first of the semiconductor switching elements is positioned at a first region of the conductive plates, and a second of the semiconductor switching elements positioned at a second region of the conductive plates. At least one of the conductive plates includes an aperture positioned between the first region and the second region of the conductive plates, such that in a compressed state, a contact surface of the conductive plate associated with the first region is substantially parallel to and offset from that of the second region in a direction parallel to the direction of compression.

Abstract: A cryogenically-cooled HTS cable is configured to be included within a utility power grid having a maximum fault current that would occur in the absence of the cryogenically-cooled HTS cable. The cryogenically-cooled HTS cable includes a continuous liquid cryogen coolant path for circulating a liquid cryogen. A continuously flexible arrangement of HTS wires has an impedance characteristic that attenuates the maximum fault current by at least 10%. The continuously flexible arrangement of HTS wires is configured to allow the cryogenically-cooled HTS cable to operate, during the occurrence of a maximum fault condition, with a maximum temperature rise within the HTS wires that is low enough to prevent the formation of gas bubbles within the liquid cryogen.

Abstract: A cryogenically-cooled HTS cable is configured to be included within a utility power grid having a maximum fault current that would occur in the absence of the cryogenically-cooled HTS cable. The cryogenically-cooled HTS cable includes a continuous liquid cryogen coolant path for circulating a liquid cryogen. A continuously flexible arrangement of HTS wires has an impedance characteristic that attenuates the maximum fault current by at least 10%. The continuously flexible arrangement of HTS wires is configured to allow the cryogenically-cooled HTS cable to operate, during the occurrence of a maximum fault condition, with a maximum temperature rise within the HTS wires that is low enough to prevent the formation of gas bubbles within the liquid cryogen.

Abstract: In a general aspect, a power conversion system includes a power converter, a transformer, and a voltage adjustment device. The power converter is configured to receive a variable DC power generated by a power generation device and to convert the received DC power to AC power at a first voltage. The transformer is configured to receive the AC power from the power converter and to deliver AC power at a second voltage to a utility power network. The voltage adjustment device is configured to adjust the first voltage to a target value determined on the basis of a voltage of the DC power.

Abstract: An apparatus for harvesting solar power includes a photovoltaic array for generating a DC voltage; a discharge circuit for causing the DC voltage to decay from a first value to a second value; and an inverter circuit for transforming an output voltage from the discharge circuit into an AC voltage.

Abstract: A method of controlling fault currents within a utility power grid is provided. The method may include coupling a superconducting electrical path between a first and a second node within the utility power grid and coupling a non-superconducting electrical path between the first and second nodes within the utility power grid. The superconducting electrical path and the non-superconducting electrical path may be electrically connected in parallel. The superconducting electrical path may have a lower series impedance, when operated below a critical current level, than the non-superconducting electrical path. The superconducting electrical path may have a higher series impedance, when operated at or above the critical current level, than the non-superconductor electrical path.

Abstract: A superconducting transformer system is configured to be included within a utility power grid having a known fault current level. The superconducting transformer system includes a non-superconducting transformer interconnected between a first node and a second node of the utility power grid. A superconducting transformer is interconnected between the first node and the second node of the utility power grid. The superconducting transformer and the non-superconducting transformer are electrically connected in parallel. The superconducting transformer has a lower series impedance than the non-superconducting transformer when the superconducting transformer is operated below a critical current level and a critical temperature. The superconducting transformer is configured to have a series impedance that is at least N times the series impedance of the non-superconducting transformer when the superconducting transformer is operated at or above one or more of the critical current level and the critical temperature.

Abstract: A method of making a laminated superconductor wire includes providing an assembly, where the assembly includes a substrate; a superconductor layer overlaying a surface of the substrate, the superconductor layer having a defined pattern; and a cap layer; and slitting the assembly in accordance with the defined pattern of the superconductor layer to form a sealed wire. Slitting the assembly in accordance with the defined pattern may form multiple sealed wires, and the substrate may be substantially wider than the sealed wires.

Abstract: Power compensation is provided from a power compensation device to a utility power network carrying a nominal voltage. The power compensation device has a steady-state power delivery characteristic. The power compensation is providing by detecting a change of a predetermined magnitude in the nominal voltage on the utility power network and controlling the power compensation device to deliver, for a first period of time and in response to the detected change in the nominal voltage, reactive power to the utility power network. The power compensation device is controlled to deliver, for a second period of time following the first period of time, reactive power to the utility power network at a level that is a factor N(N>1) greater than the steady-state power delivery characteristic of the power compensation device.