778results about How to "Good dynamic response" patented technology

An apparatus and method of control for converting DC (direct current) power from a solar photovoltaic source to AC (alternating current) power. A novel DC-to-AC power converter topology and a novel control method are disclosed. This combination of topology and control are very well suited for photovoltaic microinverter applications. Also, a novel variant of this control method is illustrated with a number of known photovoltaic DC-to-AC power converter topologies. The primary function of both control methods is to seek the maximum power point (MPP) of the photovoltaic source with novel, iterative, perturb and observe control algorithms. The control portion of this invention discloses two related control methods, both an improvement over prior art by having greatly improved stability, dynamic response and accuracy.

The method of the present invention turns off the line of LEDs of a backlight module behind the currently enabled scanline of a LCD device so that the transient behavior of the liquid crystal molecules are less obvious, thereby enhancing the dynamic response of the LCD device. For one type of embodiments, in accordance with the top-down scanning of the LCD device, the corresponding horizontal lines of the LEDs of the backlight module are turned off in a certain manner so that they exhibit a lighting (or, more precisely, darkening) pattern as if they are also “scanned” from top to down. For another type of embodiments, the horizontal lines of the LEDs of the backlight module are turned off and on simultaneously so that the backlight module actually “flashes” the LCD device.

A combined pressure and temperature transducer (10) particularly adapted for high temperature fluids has a sensing element assembly mounted at the tip of a tubular probe (20) which is arranged for placement in a fluid flow path. A sensing element (12) includes a pressure responsive diaphragm (12g) closing the open end of the tubular probe and being provided with piezo-resistive gauge elements bonded to the diaphragm. Wires are bonded between the gauge elements and a first, heat resistant, printed circuit board (PCB). The first PCB, together with the piezo-resistive elements, form a Wheatstone bridge. An inner connector (26) mounts elongated, axial stress absorbing contacts connecting the first PCB at one end of the inner connector with a second printed circuit board (PCB) mounted at the opposite end of the inner connector physically removed from the sensing element and first PCB and away from the fluid flow path. The second PCB mounts signal conditioning and amplifying electronics. An outer connector (38) and housing (42) mounts the second PCB and provides an electrical interface with transducer.

A sensor arrangement (1) for measuring a pressure and a temperature in a fluid is disclosed. The sensor arrangement (1) comprises a temperature sensitive electrical element (3) and a pressure sensing electrical element (6), the temperature sensitive electrical element (3) and pressure sensing electrical element (6) are both coupled to one side of a metallic membrane structure (4,16). The metallic membrane structure is arranged to pass on the temperature of the fluid which is at the other side of the membrane structure (4,16) to the temperature sensitive electrical element (3) and to pass on the pressure in the fluid to the pressure sensing electrical element (6). In this way a combined pressure and temperature sensor is obtained which is applicable in vehicle air-conditioning systems working with CO₂ as refrigerant.

An area-efficient capacitor-free low-dropout regulator based on a current-feedback frequency compensation technique is disclosed. An implementation of a current feedback block with a single compensation capacitor is used to enable capacitance reduction. The resultant low-dropout regulator does not generally require an off-chip capacitor for stability and is particularly useful for system-on-chip applications.

A voltage controller and method providing multiple modes of operation. Embodiments include pulse-width modulation (PWM), feed-forward (FF), pulse-frequency modulation (PFM) and skip operation (PWM-FF-PFM/SKIP). Controller embodiments have integrated MOSFET components, comparator hysteresis, oscillator feed-forward, fixed gain, and error amplifier (EA) limits thereby providing improved efficiency and noise immunity.

A powertrain for transmitting power in a vehicle includes a prime mover having a relatively slow transient response, and a storage device for storing energy in a predetermined form. A transmission includes an input driveably connected to the prime mover and an output driveably connected to vehicle drive wheels, producing a range of ratios of a speed of the output to a speed of the input that varies from negative to positive and includes zero. An energy conversion device, driveably connected to the prime mover and drive wheels, converts rotational power transmitted to the energy conversion device from the wheels and the prime mover to a form of energy that can be stored in the storage device, and drives the wheels using energy supplied to the energy conversion device from the storage device. A control device alternately transmits energy from the storage device to the energy conversion device, and transmits energy from the energy conversion device to the storage device.

The invention provides a low-voltage ride through (LVRT) control system of a photovoltaic inverter and a method thereof. The system comprises a solar cell panel, a photovoltaic inverter, a power grid and a controller, wherein the solar cell panel, the photovoltaic inverter and the power grid are sequentially connected; and the controller is respectively connected with the photovoltaic inverter and the power grid. The system and the method have the advantages that 1) when the power grid breaks down to cause power grid voltage balance sag, good dynamic response is provided, and grid-connected current can be steadily outputted by three phases of current sharing of the photovoltaic inverter; and 2) in unbalanced voltage sag, the positive and negative sequence voltage influence of the power grid can be eliminated by the control system, only the positive sequence current component is outputted, and the three-phase current sharing is ensured and has a lower harmonic component, so that the loss caused by the faults of the power grid is reduced, and the power supply reliability of the power grid is improved. The special situation of the unbalanced power grid is supported by the system, and the stable operation of the normal three-phase current sharing is guaranteed.

The invention relates to a four-degree-of-freedom optical measuring head based on semiconductor laser components. Including the probe mechanism and the target mirror mechanism; the probe mechanism includes semiconductor lasers, four-quadrant photodetectors, two-dimensional PSD position sensitive detectors, optical isolators and plano-convex lenses; the target mirror mechanism includes half-transparent mirrors and corner cubes; When used for measurement, the measuring head mechanism is fixed on the workbench, and the target mirror mechanism is fixed on the main shaft of the power head. The light beam emitted by the semiconductor laser is divided into two beams after passing through the polarizing beam splitter. One of the beams is incident on the half-mirror, and 50% of the light will pass through the half-mirror and enter the corner-cube prism, and then pass through the corner-cube prism. Reflected onto the four-quadrant detector, it is used as a reference beam for measuring two-dimensional linear displacement X, Y. The other half of the beam incident on the half-mirror will return along the original path and enter the beam splitter again, be reflected vertically to the plano-convex lens, and then be collimated and focused on the two-dimensional PSD by the plano-convex lens, which is used as the angle error (pitch angle , deflection angle) of the reference beam.

A digital slope compensation apparatus and method for a switched-mode power supply use a sensor for sensing and generating an analog inductor current (i_L) of the switched-mode power supply, a comparator (2) for generating a trigger signal according to a comparison of an analog current threshold level and the analog inductor current (i_L), and a pulse width modulator (PWM) for controlling the operation of a switched-mode power supply, wherein the pulse width modulator (PWM) is arranged to be triggered by the trigger signal of the comparator. A first analog to digital converter is arranged for converting an analog output voltage (V_out) of the switched-mode power supply into a digital output voltage, means are arranged for transforming the digital output voltage into a digital current threshold level (i_cmp) and a digital to analog converter is arranged for generating the analog current threshold level according to the digital current threshold level (i_cmp).

The invention relates to a rotary inertia identification method of an alternating-current servomechanism, the load inertia and the rotor inertia of a motor are regarded as a whole inertia, a servo system does an accelerated motion and a decelerated motion, so as to obtain the system output torque and the motor average rotate speed for a period of time. The average torque of the servo system can be obtained by the system output torque, the value of the whole inertia can be obtained according to the motor average rotate speed, the average torque of the servo system, and the total operation time of the accelerated motion and the decelerated motion of the system, that is, the rotary inertia of the alternating-current servomechanism can be identified. The invention does not need to singly identify the load inertia or the load torque for identifying the system rotary inertia, but causes the load inertia and the motor rotary inertia to be regarded as an inertia, and the identification of the system rotary inertia can be realized by combining the system output torque. The implementation of the method is simple, the use is convenient, the identified inertia precision is higher, and the method can be applied to the servo system inertia detection of a permanent magnetism synchronous servo-actuator.

The invention provides a finished hybrid power automobile torque distribution system and method based on parallel control and relates to the field of hybrid power automobile control. The finished hybrid power automobile torque distribution system based on the parallel control consists of a real system and an artificial system, wherein the real system is responsible for driving of actual running of a real automobile, the artificial system is responsible for real automobile modeling and controller parameter optimization in a real automobile real-time running state and parallel execution. The real system consists of a sensor detection circuit, a signal conditioning circuit, a controller and a liquid crystal display. The artificial system consists of a sensor detecting circuit, a signal conditioning circuit and a computer processing system. The finished hybrid power automobile torque distribution system based on the parallel control is simple in structure, easy to achieve and high in reliability, improves the engine fuel utilization rate, reduces emission and effectively improves the actual running performance and working efficiency of the real automobile within a whole service life.

The invention discloses a STATCOM (static synchronous compensator) control system adopting a droop control strategy and a control method thereof. The STATCOM control system adopting the droop control strategy comprises a direct-current side capacitor, a three-phase inverter bridge and an inductance-capacitance filter, wherein the direct-current side capacitor and the three-phase inverter bridge are connected in parallel and then connected with the inductance-capacitance filter, and the inductance-capacitance filter is connected to a PCC (Point of Common Coupling) of a power grid by a three-phase switch K through a coupling transformer T. The control method disclosed by the invention comprises the steps of real-time signal collection, computation of active power reference value P*, computation of reactive power reference value Q*, computation of frequency reference value omega* and voltage modulation amplitude reference value E*, computation of phase reference value Delta* and computation of voltage modulation signals; and only one PI (proportional integral) regulator and two droop control coefficients need to be regulated, thus the whole control method is easy to realize, and further the power system can better supply power to users safely, excellently and economically.

The invention relates to a special display platform for new energy automobile parts. The special display platform comprises a bottom board, wherein four universal wheels are symmetrically arranged on the lower end surface of the bottom board, through the four universal wheels, the special display platform can be moved to the needed display place, the mobility is good, and a rigid support device is mounted in the middle of the upper end surface of the bottom board; a rotation shaft is mounted on the middle part of the upper end surface of an operation table through a bearing, a display stand is welded to the upper end surface of the rotation shaft, and the upper end of the rotation shaft is mounted on a concave bracket through a bearing; the lower end of the concave bracket is welded to the operation table; a driven gear is mounted in the middle of the rotation shaft through a key, and is meshed with a drive gear, the drive gear is fixed on an output shaft of a rotation motor, and the rotation motor is mounted on the operation table through a motor base. With the special display platform, the function of simultaneously and dynamically displaying a plurality of new energy automobile parts can be achieved, meanwhile, the display height is adjustable, and the display effect is good.

A wind energy installation control device includes a wind rotor, a generator driven by the wind rotor, a torque control unit configured to control a torque of the generator, and a control system. The control system includes a detector configured to identify a grid dip and an end of the grid dip, a residual torque transmitter configured to provide a preset value for a torque of the generator after identification of the grid dip, and an initializer configured to initialize a component of the torque control unit at the preset value. Accordingly, upon return of grid power after a grid dip, the vibration behaviour of a wind power system can be significantly improved. Overload of a drive train upon return of grid voltage can thus be reduced.

The invention belongs to the technical field of automobile energy-saving equipment, and relates to a regenerative braking energy storage device for an electric automobile. An ultracapacitor module stores the regenerative braking feedback energy of the electric automobile and is connected in parallel with a storage battery to power an electric motor when the electric automobile starts and accelerates; an ultracapacitor charge-discharge controller is electrically connected with the ultracapacitor module, the storage battery and the driving controller respectively; the ultracapacitor charge-discharge controller is electrically communicated with the ultracapacitor module to control the charge-discharge process; and the driving controller is electrically communicated with the electric motor to achieve control operation of the electric motor. According to the invention, ultracapacitors store the regenerative braking feedback energy of the electric motor car to prevent adverse effects on the power supply of the electric automobile due to frequent charge and discharge, so as to achieve a long service life, and the ultracapacitors have high power density and good dynamic response.

The invention discloses a high-temperature ceramic base film thermocouple and a manufacturing method of the high-temperature ceramic base film thermocouple, and belongs to the field of sensor manufacturing technologies and high temperature measurement technologies. The high-temperature ceramic base film thermocouple sequentially comprises a ceramic base 1, a SiO2 layer 2, a first A12O3 layer 3, an interlayer 4, a second A12O3 layer 5, a thermocouple layer 6 and a third A12O3 layer 7. The high-temperature ceramic base film thermocouple has the advantages that (1) the SiO2 transition layer is adopted, so that binding force on the interface between an insulating layer and the ceramic base is enhanced; (2) the A12O3-Si3N4/A1N-A12O3 composite insulating layer is adopted, the excellent insulating performance is possessed, oxygen can be prevented from entering the high-temperature ceramic base film thermocouple, oxidization of a film on an inner layer is eliminated, and good dynamic response of a sensor is guaranteed; (3) thermal stress of the film caused by thermal loads is effectively reduced, and film forming quality and stability of the film are guaranteed.

A design method of an aeroelastic model for a long-span transmission tower-line system is disclosed. On the basis of boundary layer wind tunnel test data of a rigid model, a finite element model is utilized to calculate that relaxed Froude number similarity criterion of transmission towers, the influence of the elastic stiffness of a transmission line and two kinds of variable proportion transmission line models upon wind-induced response is changed, an aeroelastic model with long span is designed. The influence of material nonlinearity and gradient wind height of concrete filled steel tube onwind-induced response is further analyzed by the finite element model. The method has the advantages that the aeroelastic model of long span can be reasonably designed by increasing the elastic stiffness of the transmission line and adopting an accurate line length similarity ratio; consideration of the material nonlinearity of concrete-filled steel tubes has little effect on wind-induced response at design wind speed, and the wind-induced response decreases when considering the gradient wind height.

The related control system for crystal equal-diameter growth comprises: a crystal growing furnace, a crystal diameter detection part, a control part for crucible temperature, a control part for crystal tension speed to real-time gather crystal tension speed signal and feedback to regulate the speed by algorithm of Fuzzy control and PID control, and a common controller to receive all former signal. this invention improves control precision greatly as well as the one-draw yield.

The invention discloses a carbon-based resistive flexible pressure sensor. The sensor of a four-layer film structure comprises a flexible polyimide thin film layer, a silver electrode layer, a flexible graphene and oxidized graphene composite thin film layer and an oxidized graphene film insulated protective layer. When the pressure sensor bears a pressure or bending strain occurs, the bearing condition of the pressure sensor can be obtained by measuring the resistance change of the two ends of a silver electrode. The whole carbon-based resistive flexible pressure sensor is of a film-shaped structure, the flexibility is high, and the pressure sensor can work normal in any bending angle; the sensitivity is high, and the strain coefficient ranges from 2.1 to 3; pressure measurement ranges widely from 10Pa to 900kPa; the resolution is very high, dynamic response is super-rapid, and dynamic high-frequency pressure signals reaching 10kHz can be measured; and the stability is high, and the pressure sensor passes more than 8000 repeated stability test. The pressure sensor is simple in preparation technology, low in equipment cost, suitable for wearable equipment, and can be used for measurement of physical quantities as pressure and strain.