147results about How to "Loss in efficiency" patented technology

A system (100) for connecting a fuel cell stack to an A.C. grid to provide power thereto is disclosed in which a voltage regulated D.C. bus (110) is provided to be coupled to the fuel cell stack, a bidirectional inverter (120) is coupled to the D.C. bus (110), and is to be coupled between the D.C. bus (110) and the A.C. grid. At least one D.C. auxiliary load (130) of the fuel cell stack is provided coupled to the D.C. bus (110). A D.C. to D.C. converter (140) is provided between the fuel cell stack and the D.C. bus (110).

An electroluminescent (EL) device including an illumination area having one or more primary EL emitters; a reference area having a reference EL emitter; a reference driver circuit for causing the reference EL emitter to emit light while the EL device is active; a sensor for detecting light emitted by the reference EL emitter; and a measurement unit for detecting an aging-related electrical parameter of the reference EL emitter while it is emitting light. The device further includes a controller for receiving an input signal for each primary EL emitter in the illumination area, forming a corrected input signal from each input signal using the detected light and the aging-related electrical parameter, and applying the corrected input signals to the respective primary EL emitters in the illumination area.

Apparatus for providing an analog drive transistor control signal to the gate electrode of a drive transistor in a drive circuit that applies current to an EL device, the drive circuit including a first supply electrode of the drive transistor and the EL device connected to a second supply electrode of the drive transistor, comprising a measuring circuit for measuring the current passing through the supply electrodes at different times to provide an aging signal representing variations in the characteristics of the drive transistor and EL device caused by operation of the drive transistor and EL device over time; a compensator for changing a linear code value in response to the aging signal to compensate for the variations in the characteristics of the drive transistor and EL device; and a linear source driver for producing the analog drive transistor control signal in response to the changed linear code value.

A method of setting a parameter of a peripheral device, the parameter controlling an operation of the peripheral device includes the steps of: a) collecting and storing a command issued for the peripheral device by an external device; b) analyzing a command issue pattern for the peripheral device based on the command stored in the step a); c) determining a most proper value of the parameter based on the command issue pattern; and d) setting the most proper value of the parameter determined in the step c) as a parameter for controlling the operation of the peripheral device.

In a Doherty amplifier (100), the amplifier's input is connected to a main device (102) via a first branch and to a peak device via a second branch. The first branch has a first frequency-dependent input impedance with a first real part and a first imaginary part. The second branch has a second frequency-dependent input impedance with a second real part and a second imaginary part. The first and second imaginary parts have opposite polarity. The first and 5 second imaginary parts have a same magnitude so as to compensate each other in the frequency band. The first imaginary part and the second imaginary part implement a first phase shift in the. first branch and a second phase shift in the second branch, respectively. The first and second phase shifts each have a magnitude of substantially 45 degrees substantially in the middle of the frequency band and are of opposite polarity. The phase difference of the 10 input signals to the main (102) and peak (104) devices stays largely constant over the frequency band.

A soap dispenser can be configured to dispense an amount of liquid soap, for example, upon detecting the presence of an object. Certain embodiments of the dispenser include a housing, reservoir, pump, and nozzle. In some embodiments, the dispenser includes a bypass passage, which can facilitate priming of the pump. In certain embodiments, the dispenser is configured to inhibit or avoid the formation of an air bubble that could obstruct the liquid soap from entering the pump. In some embodiments, the pump includes engaging gears, which can include a plurality of teeth with substantially pointed tips. In certain embodiments, the nozzle comprises a one-way valve, such as a duckbill valve. Some embodiments of the one-way valve are shaped or otherwise configured to provide certain biases to the valve, which can, for example, facilitate rapid opening and closing of the valve.

An annular circulation chamber is arranged in an interior of a compressor housing, which circulation chamber radially surrounds a main flow duct and extends from an intake region to an encircling circulation opening in a region of rotor blades of the compressor wheel. Between the circulation openings, the circulation chamber is delimited from the main flow duct by an annular contoured wall. The contoured wall is connected to the inner compressor housing by plural struts which are spaced apart from one another to different extents in the circumferential direction. As a result of the irregular distribution of the struts in the circumferential direction, generation of undesired vibration excitations can be reduced and / or eliminated.

A converter control device comprises: a voltage-zero-cross detection unit detecting zero cross of the alternate-current voltage and outputting a voltage zero-cross signal; a power-source-current detection unit detecting a power source current of the alternate-current power source; a bus-line-voltage detection unit detecting a bus-line voltage between terminals of the smoothing capacitor; a PWM-signal generation unit generating a PWM-signal for on / off-controlling the switching unit, based on the power-source current, the bus-line voltage and a bus-line-voltage command value as a target voltage of the bus-line voltage; a power-source voltage-state detection unit detecting a signal state of the alternate-current voltage based on the voltage zero-cross signal; and a fundamental-switching-frequency selection unit selecting a fundamental switching frequency of the PWM-signal based on the signal state of the alternate-current voltage. The PWM-signal generation unit generates the PWM-signal based on a fundamental switching signal having a fundamental switching frequency selected by the fundamental-switching-frequency selection unit.

A motor drive apparatus and motor drive method reduce vibration and acoustic noise by not requiring a non-activation period for rotor position detection, and enable stable, high efficiency motor drive. A control voltage generator generates a control voltage based on the frequency of the speed signal FG output from a speed detection unit, and the amplitude of the control voltage is controlled based on a torque control signal EC. The phase difference generator detects the phase difference between the control voltage and the zero cross signal of the motor current detected from the motor terminal voltages. A control voltage generator controls the phase of the control voltage so that the phase difference goes to zero, thus accomplishing sensor-less motor drive.