Abstract: While motors or generators stacked in series may allow for higher operating voltages, such motors or generators may also exhibit instability. To minimize instability, the motors or generators may be controlled to have an approximately equal current. An example motor system may include motor stacks connected in series, each motor stack exhibiting a respective stack voltage and a respective differential power (based on a difference in power between motors in the motor stack). A control system may average the stack voltages to generate an average stack voltage and generate a nominal stack power corresponding to each stack voltage. The control system may receive the differential powers, combine each differential power and nominal stack power for the respective motor stack to generate first and a second motor powers, and control each motor stack using the first and second motor powers.

Abstract: In one aspect, a method is described. The method may include operating a plurality of circuit elements, and operating a plurality of magnetically-coupled power-balancing circuits. Each individual power-balancing circuit may be electrically coupled in parallel to a respective circuit element and each individual power-balancing circuit may include a first switch and a second switch (or perhaps more than two switches). The method may include designating one power-balancing circuit of the plurality of power-balancing circuits as a primary power-balancing circuit, and alternately toggling the first switch and the second switch of the primary power-balancing circuit in accordance with a first duty cycle.

Abstract: A method may involve transmitting power between a tethered aerial vehicle equipped with wind turbines for generating power and a ground station configured to interconnect the generated power to an electrical distribution network. The power may be transmitted using high voltage, high frequency AC electrical signals, and transformers at the ground station and the aerial vehicle can scale the AC voltage for use at the respective locations. Converters at the ground station and the aerial vehicle can then convert the transformed voltage to DC. The AC voltage may be transmitted through the tether at a resonant frequency of the tether based in part on an internal capacitance between multiple conductive paths on the tether.

Abstract: It can be difficult to remove atomically thin films, such as graphene, graphene-based material and other two-dimensional materials, from a growth substrate and then to transfer the thin films to a secondary substrate. Tearing and conformality issues can arise during the removal and transfer processes. Processes for forming a composite structure by manipulating a two-dimensional material, such as graphene or graphene-base material, can include: providing a two-dimensional material adhered to a growth substrate; depositing a supporting layer on the two-dimensional material while the two-dimensional material is adhered to the growth substrate; and releasing the two-dimensional material from the growth substrate, the two-dimensional material remaining in contact with the supporting layer following release of the two-dimensional material from the growth substrate.

Abstract: A method may involve transmitting power between a tethered aerial vehicle equipped with wind turbines for generating power and a ground station configured to interconnect the generated power to an electrical distribution network. The power may be transmitted using high voltage, high frequency AC electrical signals, and transformers at the ground station and the aerial vehicle can scale the AC voltage for use at the respective locations. Converters at the ground station and the aerial vehicle can then convert the transformed voltage to DC. The AC voltage may be transmitted through the tether at a resonant frequency of the tether based in part on an internal capacitance between multiple conductive paths on the tether.

Abstract: Disclosed are systems and rotor/stator assemblies with improved electrical isolation. An example rotor/stator assembly may include a rotor, a rotor housing, a rotor insulator, a stator, a stator plate, and a stator insulator. The rotor may be electrically isolated from the rotor housing by the rotor insulator, and the stator may be electrically isolated from the stator plate by the stator insulator. The stator may be disposed coaxial to the rotor. In some embodiments, the rotor/stator assembly may function as a motor, and the stator may be configured to cause the rotor to rotate about the stator in response to an input of electrical energy to the stator. Alternatively or additionally, the rotor/stator may function as an electrical generator. The rotor may be configured to rotate about the stator, and the stator may be configured to produce electrical energy in response to rotation of the rotor relative to the stator.

Abstract: While motors or generators stacked in series may allow for higher operating voltages, such motors or generators may also exhibit instability. To minimize instability, the motors or generators may be controlled to have an approximately equal current. An example motor system may include motor stacks connected in series, each motor stack exhibiting a respective stack voltage and a respective differential power (based on a difference in power between motors in the motor stack). A control system may average the stack voltages to generate an average stack voltage and generate a nominal stack power corresponding to each stack voltage. The control system may receive the differential powers, combine each differential power and nominal stack power for the respective motor stack to generate first and a second motor powers, and control each motor stack using the first and second motor powers.

Abstract: While motors or generators stacked in series may allow for higher operating voltages, such motors or generators may also exhibit instability. To minimize instability, the motors or generators may be controlled to have an approximately equal current. An example motor system may include motor stacks connected in series, each motor stack exhibiting a respective stack voltage and a respective differential power (based on a difference in power between motors in the motor stack). A control system may average the stack voltages to generate an average stack voltage and generate a nominal stack power corresponding to each stack voltage. The control system may receive the differential powers, combine each differential power and nominal stack power for the respective motor stack to generate first and a second motor powers, and control each motor stack using the first and second motor powers.

Abstract: A photo-voltaic (PV) power generating system and a control system for PV array string-level control and PV modules serially-connected into strings of PV modules. The system includes plural parallel strings of serially-connected power-generating photovoltaic modules that form a PV array, DC/DC micro-converters that are coupled to a DC voltage buss and to the output of a corresponding photovoltaic module or to the output of a string of photovoltaic modules; a gating or central inverter; and a control system. The micro-converters are structured and arranged to include at least one of: an active clamp device, a ground fault detection device, and a fractional power converter that injects power in series or in parallel with voltage or current from the power-generating portion onto the DC buss.

Abstract: A surge protection arrangement for protecting against an overvoltage condition in an electrical circuit having a power source and an electrical load includes a reactive component (such as a capacitor or an inductor) and a switching circuit connected to the reactive component. The switching circuit causes surge energy to flow to the reactive component in response to an overvoltage condition in the electrical circuit so that the surge energy is stored in the reactive component.

Abstract: A photo-voltaic (PV) power generating system and a control system for PV array string-level control and PV modules serially-connected into strings of PV modules. The system includes plural parallel strings of serially-connected power-generating photovoltaic modules that form a PV array, DC/DC micro-converters that are coupled to a DC voltage buss and to the output of a corresponding photovoltaic module or to the output of a string of photovoltaic modules; a gating or central inverter; and a control system. The micro-converters are structured and arranged to include at least one of: an active clamp device, a ground fault detection device, and a fractional power converter that injects power in series or in parallel with voltage or current from the power-generating portion onto the DC buss.

Abstract: A photo-voltaic (PV) power generating system and a control system for PV array string-level control and PV modules serially-connected into strings of PV modules. The system includes plural parallel strings of serially-connected power-generating photovoltaic modules that form a PV array, DC/DC micro-converters that are coupled to a DC voltage buss and to the output of a corresponding photovoltaic module or to the output of a string of photovoltaic modules; a gating or central inverter; and a control system. The control system is structured and arranged to control and manage each string of photovoltaic modules, to ensure that power delivered by the photovoltaic power generating system is not affected by photovoltaic modules or strings of photovoltaic modules that are not operating at maximum power transfer efficiency.

Abstract: An electronic semiconductor package is described. The package has a wide band gap electronic semiconductor device requiring heat removal. On one side of the electronic semiconductor device is a first, thermally-conductive, electrically-insulative substrate having a predetermined electrically-conductive wire pattern affixed thereto. On the other side of the electronic semiconductor device is a second, thermally-conductive, electrically-insulative substrate. A heat removal device is mechanically-coupled to the second substrate. The heat removal device is made of a graphite-metal or metal-matrix composite material and a fin array structure of the same material. The coefficients of thermal expansion of the heat removal device and the first and second substrates are matched to minimize internal and external stresses.

Abstract: A photo-voltaic (PV) power generating system and a control system for PV array string-level control and PV modules serially-connected into strings of PV modules. The system includes plural parallel strings of serially-connected power-generating photovoltaic modules that form a PV array, DC/DC micro-converters that are coupled to a DC voltage buss and to the output of a corresponding photovoltaic module or to the output of a string of photovoltaic modules; a gating or central inverter; and a control system. The control system is structured and arranged to control and manage each string of photovoltaic modules, to ensure that power delivered by the photovoltaic power generating system is not affected by photovoltaic modules or strings of photovoltaic modules that are not operating at maximum power transfer efficiency.

Abstract: A dietary supplement, in powder, capsule, pill, or packet form, suitable for weight reduction as well as for cholesterol lowering and general colon health, comprises a soy protein component in addition to a plurality of fiber components selected from the group consisting of soy fiber, oat fiber, psyllium, sesame flour, flaxseed, barley, indigestible dextrin, beet fiber, rice bran, guar gum, pectin, and carageenan.

Abstract: An electronic semiconductor package is described. The package has a wide band gap electronic semiconductor device requiring heat removal. On one side of the electronic semiconductor device is a first, thermally-conductive, electrically-insulative substrate having a predetermined electrically-conductive wire pattern affixed thereto. On the other side of the electronic semiconductor device is a second, thermally-conductive, electrically-insulative substrate. A heat removal device is mechanically-coupled to the second substrate. The heat removal device is made of a graphite-metal or metal-matrix composite material and a fin array structure of the same material. The coefficients of thermal expansion of the heat removal device and the first and second substrates are matched to minimize internal and external stresses.

Abstract: A monolithic wireless receiver suitable for use in a global positioning system (GPS) or other radio frequency (RF) application suitably includes a mixed-mode integrated circuit and a stacked memory device. The mixed mode integrated circuit appropriately includes a digital portion and an analog portion on a common die. The analog portion implements an RF receiver circuit, and the digital portion includes a signal processor that communicates with the RF receiver. The memory device appropriately communicates with the integrated circuit to store electronic instructions and data for the signal processor. The monolithic receiver may be conveniently integrated into a portable electronics device such as a camera, personal digital assistant (PDA), portable phone or the like to provide location sensing or other RF functionality.

Abstract: A monolithic wireless receiver suitable for use in a global positioning system (GPS) or other radio frequency (RF) application suitably includes a mixed-mode integrated circuit and a stacked memory device. The mixed mode integrated circuit appropriately includes a digital portion and an analog portion on a common die. The analog portion implements an RF receiver circuit, and the digital portion includes a signal processor that communicates with the RF receiver. The memory device appropriately communicates with the integrated circuit to store electronic instructions and data for the signal processor. The monolithic receiver may be conveniently integrated into a portable electronics device such as a camera, personal digital assistant (PDA), portable phone or the like to provide location sensing or other RF functionality.

Abstract: A plastic number plate cover that can be installed from the exterior of the housing faceplate of a public telephone and which is resistant to tampering. The cover includes an envelope-shaped pocket into which a number plate or card is inserted, and opposed cantilever arms each terminating in a tab having a beveled edge. The cover is inserted into a rectangular-shaped recess on the faceplate when the tabs are brought into contact with a recess edge, causing the arms to flex and allowing the beveled edges to slide past the recess edge. The cover may be fixed or removable once installed within the faceplate, depending on the structure of the tabs.