130 results about "Resistive loss" patented technology

PCT No. PCT / NZ95 / 00084 Sec. 371 Date Feb. 28, 1997 Sec. 102(e) Date Feb. 28, 1997 PCT Filed Sep. 14, 1995 PCT Pub. No. WO96 / 08683 PCT Pub. Date Mar. 21, 1996A solar concentrator for producing usable power as heat and / or electricity uses a self-steering heliostat 1502 to concentrate solar radiation 1509 onto an absorbing surface such as, or including, a solar cell array 1511 capable of absorbing power from the radiation, meanwhile removing heat (such as from long-wave infra-red radiation or resistive losses) from the surface with fluid heat transfer means 1503, 1504, then making effective use of that low-grade heat. Thus the solar cell array is kept relatively cool and a larger proportion of the solar energy incident on the reflector unit is used. The invention uses electricity 1506 from the solar cells to move a transporting fluid through a heat exchanger 1504. Excess electricity may be available for local storage or use 1510, or feeding 1512 to the power distribution grid. Applications include warming swimming pools 1501, heating hot-water supplies using excess electricity, or warming, lighting and ventilating open spaces.

A high power low RPM direct current electric motor is disclosed whereby the high power output is achieved in one of two ways or both. In the first case, the need for cooling is reduced simultaneously along with an increase in the utilization of the magnetic field present in the motor permanent magnets. This is achieved by wrapping the electromagnet core with windings that are capable of demagnetizing the rotor permanent magnets under stall conditions. Interlocking motor circuitry is provided which prevents the full activation of these motor windings until motor RPM values reach a safe level. This increases motor power while decreasing resistive losses in electromagnet windings. In the second case, the rotary portion consists of a large diameter relatively flat rotor containing permanent magnets and having built in vanes for moving air over the electromagnet stator windings providing forced air cooling.

A high power low RPM direct current electric motor is disclosed whereby the high power output is achieved in one of two ways or both. In the first case, the need for cooling is reduced simultaneously along with an increase in the utilization of the magnetic field present in the motor permanent magnets. This is achieved by wrapping the electromagnet core with windings that are capable of demagnetizing the rotor permanent magnets under stall conditions. Interlocking motor circuitry is provided which prevents the full activation of these motor windings until motor RPM values reach a safe level. This increases motor power while decreasing resistive losses in electromagnet windings. In the second case, the rotary portion consists of a large diameter relatively flat rotor containing permanent magnets and having built in vanes for moving air over the electromagnet stator windings providing forced air cooling.

A pulse-width modulated buck regulator includes a feedback control without having any external frequency compensation components to stabilize the feedback control loop irrespective of the reactive component of its load impedance. Additionally, the output voltage is maintained constant not only with feedback but also using a power supply voltage compensation scheme. Thus, the feedback control compensates for resistive losses, thus minimizing hardware. The output voltage is compared with first and second reference voltages. If the output voltage is greater than the first reference voltage, a counter's count is decremented. If the output voltage is less than the second reference voltage, the counter's count is incremented. The counter is disabled if the output voltage is smaller than the first reference voltage and greater than the second reference voltage. The duty cycle of the output voltage is varied in accordance with the counter's count.

A high efficiency control circuit for operating a switching regulator is provided. The switching regulator can regulate an output voltage no matter the input voltage is higher, lower, or close to the output voltage. The switching regulator has first, second, third and fourth switches. The control circuit can operate the switching regulator in buck mode, boost mode, or buck-boost mode. In a buck-boost mode, the control logic drives the four switches in an efficiency sequence for reducing energy consumption during the switch transition, on the other side, resistive loss owing to the energy transfer phase is also minimized. Furthermore, the invention is capable of control duty cycle limitation to fit the consideration of the linearity of the converter.

The field of the invention relates to minimization of resistive loss of solar panels in order to achieve maximum solar energy conversion efficiency, extracting more electricity power from available solar irradiance. Schemes are designed to take advantage of the geometrical and mechanical configurations of back contact solar cells to make better electrical contacts and connections so as to achieve maximum solar energy conversion efficiency and better power extraction.

It is described a high efficiency rectification stage using dynamic threshold MOSFET. The idea is to use the input signal to reduce the threshold voltage when the transistor has to be on, and to increase the threshold when the transistor has to be off. This allows reducing both the resistive losses and the leakage current. A matching network allows the generation of a second higher voltage signal to drive the control gates and the bulk, i.e. the wells, of the transistors. Further, a self-tuned front-end is provided to extend the bandwidth of the high-Q charge pump.

A notch filter suitable for attenuating certain frequencies of a radio-frequency signal includes an input for receiving the radio-frequency signal and an output for the output of a portion of the radio-frequency signal, first and second capacitive means, at least one inductor and a negative resistance circuit suitable for compensating the resistive losses of said at least one inductor. The inductor and the first and second capacitive means are placed to produce a resonator and the filter comprises a control device suitable for controlling the negative resistance circuit. The input impedance of the filter comprises a pole and a zero, with the pole depending on the second capacitive means and the zero depending on both the first and second capacitive means. The first and second capacitive means are variable and the control device is suitable for controlling the first and second capacitive means.

An inductor includes an elongate magnetic core, a coil wrapped around the core and a spacer that separates the coil from the core to provide a coolant passage between the coil and the core. The coolant passage may include an air passage that extends substantially parallel to an axis of the core and that has first and second openings proximate respective first and second ends of the core. The coil may include a twisted bundle of individually insulated conductors. The inductor may be housed in a flux-tolerant compartment, i.e., a conductive aluminum structure that supports eddy currents with relatively acceptable resistive losses.

The invention discloses three-dimensional graphene-based composite wave absorbing materials, and a preparation method thereof. The three-dimensional graphene-based composite wave absorbing materials are composite materials composed of magnetic nanometer iron-based compounds and three dimensional graphene; wherein uniform in-suit growth of the magnetic nanometer iron-based compounds in the three dimensional graphene lamellar structure is realized, the structure is stable, shedding is not easily caused. A series of different magnetic nanometer iron-based compound / three dimensional graphene composite wave absorbing materials can be prepared through controlling reaction conditions; the preparation method is novel; the production period is short; the cost is low; the repeatability is high; large scale production can be realized; important reference effect is provided for preparation of graphene-base composite wave absorbing materials. According to the preparation method, the magnetic nanometer iron-based compounds with high dielectric loss and magnetic loss and graphene high in resistive loss are combined, so that wide wave absorbing frequency range and high wave absorbing intensity areachieved, excellent wave absorbing performance at low frequency zone is achieved, and practical application requirements are satisfied.

In one embodiment, a magnetometer includes an electromechanical resonator coupled to a drive-and-detect (DD) circuit. The resonator has a deformable beam that is a part of a closed current path. By applying a periodic drive signal to a drive electrode located in proximity to the deformable beam, the DD circuit induces an oscillation of the beam. In the presence of a magnetic field, this oscillation changes the magnetic flux through the closed current path, thereby generating an oscillating electrical current in the path. Dissipation of this current due to resistive losses in the closed current path then dampens the oscillation of the deformable beam with a damping coefficient that depends on the magnetic-field strength. Using a sense electrode located in proximity to the deformable beam, the DD circuit detects the oscillation amplitude. Based on the detected amplitude, the DD circuit changes the frequency of the drive signal to find the resonant frequency. Since the resonant frequency depends on the damping coefficient, the magnetic-field strength can be deduced in a relatively straightforward manner from the resonant frequency.

A system and method directed to using a PV array and laser beamed-power for aircraft and satellites is provided. More specifically, a system and method directed to a PV receiver that reduces power losses caused by variations in irradiance is provided. The use of a sloped array with a grooved cover glass coated with reflective coating allows the system and method to receive the laser beamed power at an angle and reduce any losses while producing a maximum power output. In addition, the use of capacitors in parallel with the PV cells in the array reduces resistive losses caused by short-term optical fluctuations and assists in maximizing power output for the array.

It is described a high efficiency rectification stage using dynamic threshold MOSFET. The idea is to use the input signal to reduce the threshold voltage when the transistor has to be on, and to increase the threshold when the transistor has to be off. This allows reducing both the resistive losses and the leakage current. A matching network allows the generation of a second higher voltage signal to drive the control gates and the bulk, i.e. the wells, of the transistors. Further, a self-tuned front-end is provided to extend the bandwidth of the high-Q charge pump.

Disclosed herein is a light emitting electrical package having a first electrode layer comprising a substantially transparent nonmetallic conductive material, and a plurality of light emitting elements disposed on said first electrode layer. The first electrode layer comprises a peripheral region, and an elongated bus is disposed on at least a portion of the peripheral region and adjacent the first electrode layer. The elongated bus is configured to spread current across a length dimension of said first electrode layer. Also disclosed are elongated bus structure designed intended to reduce the resistive losses along a transparent nonmetallic conductive contact at its edge or periphery. One design for an elongated bus comprises: (1) a conductive adhesive / metal foil / conductive adhesive sandwich structure; (2) another design comprises a vapor deposited bus of one or more materials; and a further design employs (1) and (2) in tandem.

An inductor includes an elongate magnetic core, a coil wrapped around the core and a spacer that separates the coil from the core to provide a coolant passage between the coil and the core. The coolant passage may include an air passage that extends substantially parallel to an axis of the core and that has first and second openings proximate respective first and second ends of the core. The coil may include a twisted bundle of individually insulated conductors. The inductor may be housed in a flux-tolerant compartment, i.e., a conductive aluminum structure that supports eddy currents with relatively acceptable resistive losses.

The present disclosure shows a hybrid regulator topology that can be more easily integrated and that can maintain high efficiency across a wide output and input voltage range, even with a small inductor. The hybrid regulator topology can include two types of regulators: a flying switched-inductor regulator and a step-down regulator that divides the input voltage into an M / N fraction of the input voltage. The disclosed embodiments of the hybrid regulator topology can reduce the capacitive loss of the flying switched-inductor regulator by limiting the voltage swing across the switches in the flying switched-inductor regulator. The disclosed embodiments of the hybrid regulator topology can reduce the inductor resistive loss of the flying switched-inductor regulator by operating the flying switched-inductor regulator at a high switching frequency and with a small amount of current flow through the inductor.

A bus system for use in electrical distribution equipment includes a generally U-shaped arrangement of conductor conductors for supplying very high amperage (e.g., above 2000 amps) alternating current to the electrical distribution system. Compared to prior-art conductor arrangements, using the present arrangement, the conductor conductors of a phase can be fabricated from less copper, which is an expensive metal. They also achieve better thermal dissipation and current distribution and mitigate skin effects. As a result, resistive losses, which increase with increased temperature, are reduced.

The invention discloses a preparation method of a carbon fiber / glass fiber hybrid invisible composite material. The preparation method includes the following steps: with carbon fibers as core yarns and glass fibers as weaving yarns, spinning the core yarns and the weaving yarns to form carbon fiber / glass fiber covered yarns through a two-dimensional weaving technology; weaving the core fiber / weaving fiber covered yarns into cloth, and performing composite curing to the cloth and epoxy resin through a resin transfer molding process to prepare the carbon fiber / glass fiber hybrid invisible composite material. Through the carbon fiber / glass fiber covered yarn structure, electromagnetic wave can enter the interior of the covered yarns as most as possible by means of wave transmission performance of the glass fiber, and then the electromagnetic energy is converted into thermal energy or energy in other forms by means of resistive loss of the carbon fibers, thus dissipating the energy. The carbon fibers are employed as core yarns, so that the material is basically in a straight status, thereby effectively achieving the mechanical performance of the material. The hybrid invisible composite material has excellent mechanical performance.

A bus system for use in electrical distribution equipment includes a generally U-shaped arrangement of conductors for supplying very high amperage (e.g., above 2000 amps) alternating current to the electrical distribution system. Compared to prior-art conductor arrangements, using the present arrangement, the conductors of a phase can be fabricated from less copper, which is an expensive metal. They also achieve better thermal dissipation and current distribution and mitigate skin effects. As a result, resistive losses, which increase with increased temperature, are reduced.

A method and apparatus are disclosed for filtering a signal, such as a transmit communication signal with a configurable notch filter. The configurable notch filter may attenuate a set of frequencies near a selected notch frequency. In some embodiments, the configurable notch filter may include a variable resistor, a variable capacitor, a first inductor, and a second inductor. The variable resistor may be configured to compensate for resistive losses within the configurable notch filter. The variable capacitor may be configured to determine the set of frequencies to be attenuated.

The invention discloses a testing device for long term voltage induction and a partial discharge measurement test. The testing device for the long term voltage induction and the partial discharge measurement test uses a sine wave non-partial-discharge power source cooperatively with a non-partial-discharge exciting transformer, a non-partial-discharge compensation reactor, a non-partial-discharge voltage divider and other non-partial-discharge measurement devices, and completes the test according to a parallel resonance principle. Accordingly, in a parallel circuit composed of a non-partial-discharge variable frequency power source, a tested transformer equivalent capacitor and the non-partial-discharge compensation reactor, capacitive reactive power of a tested transformer is exactly equal to inductive reactive power of the non-partial-discharge compensation reactor, energy can be exchanged between the tested transformer equivalent capacitor and the non-partial-discharge compensation reactor, and the non-partial-discharge variable frequency power source does not need to provide reactive power to the non-partial-discharge exciting transformer and the non-partial-discharge compensation reactor, and only needs to provide resistive loss of a whole test circuit.

An electric machine includes a stator disposed about an axis in register with the rotor. The stator has a plurality of slots parallel to the axis. A plurality of windings with generally rectangular cross sections is provided with each winding having a first portion disposed radially inward of a second portion relative to the axis. At least two of the plurality of windings are at least partially inserted into each of the plurality of slots. The plurality of generally rectangular windings in each of the plurality of slots is configured to reduce resistive loss within the stator.

A method and apparatus are disclosed for filtering a signal, such as a transmit communication signal with a configurable notch filter. The configurable notch filter may attenuate a set of frequencies near a selected notch frequency. In some embodiments, the configurable notch filter may include a variable resistor, a variable capacitor, a first inductor, and a second inductor. The variable resistor may be configured to compensate for resistive losses within the configurable notch filter. The variable capacitor may be configured to determine the set of frequencies to be attenuated.

In one embodiment, a magnetometer includes an electromechanical resonator coupled to a drive-and-detect (DD) circuit. The resonator has a deformable beam that is a part of a closed current path. By applying a periodic drive signal to a drive electrode located in proximity to the deformable beam, the DD circuit induces an oscillation of the beam. In the presence of a magnetic field, this oscillation changes the magnetic flux through the closed current path, thereby generating an oscillating electrical current in the path. Dissipation of this current due to resistive losses in the closed current path then dampens the oscillation of the deformable beam with a damping coefficient that depends on the magnetic-field strength. Using a sense electrode located in proximity to the deformable beam, the DD circuit detects the oscillation amplitude. Based on the detected amplitude, the DD circuit changes the frequency of the drive signal to find the resonant frequency. Since the resonant frequency depends on the damping coefficient, the magnetic-field strength can be deduced in a relatively straightforward manner from the resonant frequency.

The current invention provides a fabrication method for large surface area, pinhole-free, ultra thin ion conducting membranes using atomic layer deposition on inexpensive sacrificial substrates to make cost effective, high performance fuel cells or electrolyzers. The resultant membrane electrode assembly (MEA) enables significant reduction in resistive losses as well as lowering of the operating temperature of the fuel cell. The invention further provides a method to deposit 3-dimensional surface conformal films that may have compositional grading for superior performance. In addition, the invention provides decoration and modification of electrode surfaces for enhanced catalytic activity and reduced polarization losses. The method of the current invention enables the MEA structure to be fabricated from the anode side up or the cathode side up, each with or without an incorporated anode current collector or cathode current collector, respectively.