54 results about "Power capture" patented technology

Described is a system for wireless energy transfer for person worn peripherals. The system makes use of a technique referred to as strongly-coupled magnetic resonance to transfer energy across a distance without wires and enables efficient transfer of energy over distances of 10 to 18 cm or more. The system comprises a resonant power source, which could be embedded in a person's equipment vest or backpack receiving power from a central battery pack or micro fuel cell, and a resonant power capture unit which could be integrated with the helmet or hand held weapon, electronic device, and the like that may be carried or handled by a person.

A digital camera system providing a low-power image capture mode includes an image capture system, an image display and a power management system. The power management system is used to provide a normal image capture mode wherein captured digital images are displayed on the image display as they are captured, and a low-power image capture mode wherein captured digital images are not displayed on the image display as they are captured. A user interface includes a first user control for selecting between the normal image capture mode and the low-power image capture mode, and a second user control for initiating a video capture operation. The system is configured such that if the first user control is activated while a digital video is being captured, the power management system switches between the normal image capture mode and the low-power image capture mode without interrupting the video capture operation.

The invention discloses a variable speed-variable pitch combined control method of a variable speed constant-frequency wind turbine generator. According to the control method, an optimal rotating speed estimated value and a rotating speed reference value are introduced to respectively serve as reference quantities of rotating speed control and variable pitch control. A rotating speed PID controller performs torque command regulation according to the deviation of the optimal rotating speed estimated value and the rated rotating speed of the wind turbine generator, a variable pitch PID controller performs pitch angle command regulation according to the deviation of the rotating speed reference value and the rated rotating speed of the wind turbine generator, decoupling control between rotating speed control and variable pitch control is achieved, and interference between rotating speed control and variable pitch control is avoided. When wind speed fluctuates nearby the rated value and pneumatic power captured by the wind turbine generator is larger than rated power, the rotating speed reference value corresponding to a pneumatic power estimated value is larger than the rated rotating speed of the wind turbine generator, the variable pitch PID controller regulates a pitch angle command before a torque command output by the rotating speed PID controller reaches the rated value, and variable speed-variable pitch combined control is achieved in advance to control rotating speed of the wind turbine generator and overshooting of output power.

A timing circuit that can function as an accurate persistent node in an RFID tag includes a power capture circuit for capturing power from a power source, and a counter circuit that provides a count representing a progression of time. The count can then be compared to a reference value representing a time constant of the circuit.

It is described a method of determining a quality of an initial value for a blade pitch angle. An initial power captured by a wind turbine is measured, while the blade pitch angle has the initial value. The blade pitch angle is changed from the initial value to a first value in a first direction. A first power captured by the wind turbine is measured and the blade pitch angle is changed to a second value in a second direction being opposite to the first direction. Further, a second power captured by the wind turbine is measured, a power difference between the first power and the second power is calculated, and the quality of the initial value based on the calculated power difference is determined. Further, a control system, a wind turbine and a computer program are described.

The invention provides a wind power plant field-level yaw control method based on a laser radar wind measuring instrument. The method comprises the following steps that wind speed data and wind direction data of the corresponding positions are measured through laser radars which are arranged in the preset positions of a wind power plant and the laser radars are arranged in preset number; the windspeed data is processed to obtain a wind power plant local single-machine wake flow model; a wake flow model of the whole wind power plant is obtained through the local wake flow model; the current yaw angle correction factors of wind turbine generator sets are calculated according to the wake flow model of the whole wind power plant; the advance wind direction information is measured through thefront-row laser radars and serves as a compensation signal for yaw of the first-row wind turbine generator set; and the wind turbine generator set yaw control is carried out on the basis of a wind direction signal of a wind speed wind indicator and a current yaw correction signal and the compensation signal. According to the control method, the measurement cost can be saved, the accuracy of the wind power plant wake flow model can be improved, and the macroscopic yaw control precision and power capture of the wind power plant are improved, the generating capacity of the wind power plant is improved, and the service life of a yaw system is prolonged.

A system and method for delivering power and means of control to a variety of wireless apparatuses by wireless means. Specifically, the batteries, used for functioning of the wireless apparatuses are replaced with a power capturing modules, and the power for such a modules are delivered externally by means of electromagnetic or / and ultrasonic waives. This named waives, that are used for delivery of a power, are also used as a carriers for control commands that are used as a signal for adjustments and manipulations, necessary for regular functioning of the named miniature wireless apparatuses during their normal exploitation.

A changeable damping wave power capturing device driven by bidirectional screw rod is provided, which uses the ball screw device to capture the wave power and prevents the energy lost caused by complex mechanism. In addition, bidirectional reciprocating rectilinear motion is changed to unidirectional rotation by the ratchet wheel device, and then the rotating energy is imported to the generating set. Besides, the wave power capturing device driven by bidirectional screw rod uses the control device to detect wave energy and choose different generator, the control device could change the damping value and improve the efficiency that transforming wave energy.

An apparatus and method for extending the power-capture region of a wind turbine during certain operating conditions is disclosed. The actual set point of an operational parameter is selected so as to be maintained at a predetermined number of standard deviations away from an operating limit during certain operating conditions. For example, the operational parameter may be a rotor / generator speed and the operating condition may be a mean wind speed that exceeds a predetermined wind speed.

The invention discloses a wind turbine yaw control method. A wind turbine is a horizontal shaft wind driven generator. The wind turbine yaw control method includes the following steps: S1, sight linewind speed and wind direction data at the corresponding position are measured through a laser radar arranged on a cabin or a rotating shaft of the wind turbine; S2, inversion wind speed and wind direction data of the radar are obtained through the sight line wind speed and wind direction data measured by the laser radar; S3, the inversion wind speed and wind direction data are substituted into a wind evolution model, and predicted current wind information of the wind turbine is calculated; and S4, wind turbine yaw control is conducted according to the calculated evolution wind speed and wind direction information and current cabin wind direction deviation information returned by a wind indicator. Wind turbine yaw without speed impact is achieved, and yaw stability is improved; the yaw lifeinterval is optimized, the power capture of the wind turbine is improved, and thus the generating capacity of the wind turbine is increased; and the additional load is lowered, and the service life of a yaw system is prolonged.

The present invention provides a cooperative control method for accessing an offshore wind plant to a traditional high-voltage direct current system, belonging to the technical field of new energy generation high-voltage direct current grid connection. The method comprises the steps of: when a wind power plant is in grid connection with a sending-end alternating current bus of a high-voltage direct current system and the system is in a stable state, starting cooperative control; and when each control period is arrived, allowing the inverter of each wind turbine generator in the wind power plant employs reactive frequency control, and allowing a high-voltage direct current rectifier to employ active-based voltage control to achieve cooperative control of the wind power plant and the high-voltage direct current system. The cooperative control method can maintain voltage stability and frequency stability when the wind power plant accesses the traditional high-voltage direct current systemin a normal condition in a condition with no need for configuration of a static var compensator so as to perform real-time transmission of the maximum power captured by the wind power plant by the high-voltage direct current system, and the wind power plant can automatically perform compensation reactive power for the high-voltage direct current rectifier.

A partial pitch wind turbine is described wherein the wind turbine blade has an inner blade section designed for stall-controlled operation and an outer blade section designed for pitch-controlled operation. The different blade profiles for the different sections allow for the efficient operation of the blade while providing for the control of the wind turbine to effectively reduce blade root moments. The outer blade sections can be pitched out of the wind to reduce root moments due to the outer blade sections, while the increasing power capture of the inner blade section maintains nominal power output.

A power converter configured to improve power capture in a wind turbine during low wind speed operation is disclosed. The power converter converts the power generated by the alternator of the wind turbine into a suitable AC current for delivery to a utility grid or to an electric load independent of the utility grid. The power converter is configured to operate in multiple operating modes, utilizing both synchronous and non-synchronous control methods, to extend the operating range of the power converter. During non-synchronous operation, the power converter utilizes a modulation routine that may either vary the dead-time compensation period during a constant modulation period or vary the modulation period with a constant on-time. A seamless transfer between non-synchronous and synchronous control methods with low total harmonic distortion (THD) improves the range of power generation for wind generators.

The invention discloses a flexible direct-current transmission wind and wave hybrid power generation system. The flexible direct-current transmission wind and wave hybrid power generation system comprises a mouse cage type tower frame platform, a wind energy subsystem, a wave energy subsystem, a power regulation unit and a flexible direct-current power transmission station; wind power generation and wave energy power generation are combined, the characteristic that dynamic response of the wave energy subsystem is rapid is fully exerted, wind power generation fluctuation power restraining and tower frame platform inclination active regulation can be achieved, the mouse cage type tower frame platform supports the wind and wave hybrid power generation system, a rigid oval floating body passively regulates the inclination angle of a tower frame, the wave energy subsystem is inversely hung on a round platform, power generation and electric modes can be rapidly switched according to the station, and power grid scheduling power and tower frame inclination angle stability can be ensured; the power regulation unit achieves wind and wave maximum power capturing and power dual-way flowing; the flexible direct-current power transmission station finishes converging and feed of wind wave capturing power. Wind and power output power and tower frame inclination angle stability can be improved,the mounting and maintaining cost can be greatly reduced, and development of the wind and wave hybrid power generation system can be promoted.

It is described a method of determining a quality of an initial value for a blade pitch angle. An initial power captured by a wind turbine is measured, while the blade pitch angle has the initial value. The blade pitch angle is changed from the initial value to a first value in a first direction. A first power captured by the wind turbine is measured and the blade pitch angle is changed to a second value in a second direction being opposite to the first direction. Further, a second power captured by the wind turbine is measured, a power difference between the first power and the second power is calculated, and the quality of the initial value based on the calculated power difference is determined. Further, a control system, a wind turbine and a computer program are described.

The invention relates to an electromagnetic-friction composite nano generator based on rolling friction, and belongs to the technical field of energy sources. The electromagnetic-friction composite nano generator comprises a friction nano power generation unit, a coil type electromagnetic induction power generation unit and a mechanical power capture unit. Each friction nanometer power generationunit comprises a roller electrode array and a friction electric material array adhered to the outer surface of the central roller. The coil type electromagnetic induction power generation unit comprises a coil and a permanent magnet in the central roller. The mechanical power capture unit includes a central drum, a shaft, and an external energy harvesting component. According to the electromagnetic-friction composite type nano-generator, the central roller and the roller electrode are driven to rotate through input conversion of external fluid energy or rotation energy, alternating current isgenerated under the contact of the roller electrode and a frictional electricity material and the action of electromagnetic induction to be supplied to a load, and collection of the external fluid energy or the rotation energy is achieved and converted into available electric energy.

The invention relates to the technical field of removing contaminants in underground water. To improve water quality by hydraulic power capturing technology and obtain good effects, the technical scheme adopted by the invention is a PRB joint control-based hydraulic power capturing method for removing the contaminants in the underground water. The method comprises steps of: 1) determining the position and the scale of a pollution source, and determining the main contaminants in the underground water; 2) collecting hydrogeological data of an research area, and determining hydrogeological parameters including the permeability coefficient, the specific yield and the infiltration supplement coefficient of the research area; 3) determining the main parameters comprising the scale and the form of a hydraulic power capturing zone, pumping load of capturing wells, the number of the capturing wells, the distance among the capturing wells, the maximum capturing width, and stationary points according to hydrogeological conditions of the site; and 4) determining the effective distance between the hydraulic power capturing zone and the PRB according to the form and size of a contamination plume, thus ensuring effective joint control to remove the contaminants in the underground water. The method is mainly used for removing the contaminants in the underground water.

The present invention discloses a control method for outputting a maximum power through wave power generation. The method comprises the steps of: measuring a working speed of a generator by a sensor,performing Kalman filtering processing of a measured value, and obtaining a speed value after filtering; performing calculation processing of the speed value after filtering according to a maximum power acquisition algorithm, and obtaining a Q-axis desired current value; performing control signal obtaining processing of the Q-axis desired current value, and obtaining control signals; and performing control of a rectifier according to the control signals to allow the generator to work in the maximum power state. Feedback input of the maximum power control through adoption of the Kalman filtering is performed, namely, the actual measured speed is filtered to obtain a feedback input speed value being closer to reality, and therefore, the control strategy accuracy can be improved, the maximumpower can be more accurately captured and the efficiency of the whole wave power generation device can be improved. The present invention further discloses a control system for outputting the maximumpower through wave power generation, a control device for outputting the maximum power through wave power generation, and a computer readable storage medium which have the beneficial effects mentionedabove.

An airborne wind energy conversion system with a ground generator and unorthodox power capture or transfer means, including such embodiments as: a system with an ultra-long flexible wing, which serves both for power harvesting and power transfer; a system with a tethered wing, the tether having an airfoil cross section in at least a substantial part of its length and participating in power harvesting; a system with a very long semi-circular wing, harvesting and transferring wind power by its helical motion; a system in which a conventional wing both harvests wind power and excites waves in the tether, the waves transferring the power.

A method for testing an integrated circuit to reduce peak power problems during scan capture mode is presented. The method comprises programming a respective duration of a first time window for each of a plurality of cores and a cache on the integrated circuit. It further comprises counting the number of pulses of a first clock signal during the first time window for each of the plurality of cores and the cache. Subsequently, the method comprises staggering capture pulses to the plurality of cores and the cache by generating pulses of a second clock signal for each of the plurality of cores and the cache during a respective second time window, wherein the number of pulses generated is based on the respective number of first clock signal pulses counted for each of the plurality of cores and the cache.

The invention discloses an integrated control method and system for a wind generating set participating in system frequency modulation. The method comprises the steps of: obtaining system frequency, of a grid connection point of a wind power plant, the wind speed v of a generator set and the rotation speed of the motor of the generator set; performing active power control by an auxiliary speed controller and an auxiliary frequency controller; and performing active power control by the auxiliary speed controller, wherein the active power control comprises: determination of the sizes of the rotation speed of the motor of the generator set, the optimal rotation speed [Omega]opt corresponding to the wind speed v of the generator set and 1.01 [Omega]opt to obtain a corresponding first mark value and determine whether the auxiliary speed controller participates in control or not according to the first mark value. Through control of the rotation speed of the motor of the generator set by theauxiliary speed controller, when the active power injected to the power grid by the generator set is larger than the maximum mechanical power captured by the generator set, the rotation speed of the motor of the generator set is continuously decreased to finally cause a phenomenon of shutdown so as to improve the robustness of the system operation.

The invention provides a zero-voltage ride-through control method for a doubly-fed wind generator, and the method comprises the following steps: determining a resistance range of a dynamic active Crowbar hardware protection circuit and performing graded input so as to limit rotor side overcurrent, absorb excess energy and protect a rotor side converter; accelerating the attenuation of a stator flux linkage by improving a flux linkage active attenuation control strategy, so the problem that a double-fed fan is out of control for a long time due to repeated input of a protection circuit is avoided; the DC voltage conversion rate is reduced by improving a grid-side converter control strategy, and the DC bus voltage rapidly tends to be stable when a severe fault occurs; the power captured by awind wheel is reduced to a greater extent within the same time by improving the variable pitch strategy of the doubly-fed wind generator, so the risk of galloping caused by rotor rotating speed risedue to energy imbalance of a fan is reduced; and DStatcom reactive power compensation is added to help to quickly recover the system voltage after the fault. According to the method, the zero-voltageride-through capacity of the doubly-fed wind generator is improved through a comprehensive control method formed through the synergistic effect of the five strategies, and the safe and stable operation of a wind power system is guaranteed and maintained.