45results about How to "Improve frequency response performance" patented technology

The invention discloses a full-wind-speed frequency response control method for a doubly-fed wind generator. According to the method, frequency response control can be conducted by actively identifying wind speed intervals and modifying a drooping coefficient in a self-adaptive mode. Firstly, the relation between the load shedding rate and the suboptimum tip speed ratio of the doubly-fed wind generator is established according to a doubly-fed wind power unit characteristic curve given by a manufacturer; a full wind speed is divided into a first wind speed interval, a second wind speed interval, a third wind speed interval and a fourth wind speed interval according to the wind speed from low to high; the division criterion of the four wind speed intervals is updated online according to the current load shedding rate of the doubly-fed wind generator; when the real-time frequency of a system is lowered and exceeds a set dead zone threshold, the wind speed intervals are identified according to collected real-time wind speed signals; real-time unit spare capacity is calculated, the drooping coefficient is modified in the self-adaptive mode, and then frequency response control is completed. By means of the method, the frequency response capability of the medium-wind-speed interval and the high-wind-speed interval can be improved, and the rotating speed of the generator in the weak-wind interval and the low-wind-speed interval can be not lower than the minimum allowed rotating speed.

The invention relates to the technical field of electric power, particularly relates to an active and passive frequency response switching control method, and specifically a frequency response controlmethod in a high-power deficiency fault. According to the method, for a two-regional power grid, a number line is adopted for representing an inter-region call wire, and an imaginary line is adoptedfor representing a communication line; A region is a disturbed region and a B region is a non-disturbed region; firstly, a unit thermal power generating unit mathematical model is established; and 2,an interconnected power grid mathematical model is established. By adoption of the method, frequency response is changed from dispersed autonomous control into concentrated coordination control, fromfeedback control into feedforward control, and from correction control to preventive control, and the overall frequency responsiveness of the system is improved under the premise of not increasing frequency response facility, thereby improving frequency stability defense capability under high disturbance; and frequency decline can be stopped effectively in a high disturbance frequency decline stage, system low frequency load shedding can be avoided, the system can be recovered to be stable in a frequency recovery stage as soon as possible, and frequency oscillation in the active control process of the system can be avoided.

A method for driving a droplet ejection device having an actuator, including applying a primary drive pulse to the actuator to cause the droplet ejection device to eject a droplet of fluid in a jetting direction, and applying one or more secondary drive pulses to the actuator which reduce a length of the droplet in the jetting direction without substantially changing a volume of the droplet.

The invention discloses a high-frequency response porous PEDOT: 1. PSS thin-film material. The preparation method is based on a high-molecular polymer PEDOT/PSS (poly 3, 4-ethylenedioxythiophene/polystyrene sulfonate). The preparation method comprises the following steps of: adding a polar cosolvent DMSO (dimethyl sulfoxide) into a PEDOT/PSS aqueous solution; uniformly stirring, spin-coating filter paper with the mixed solution, putting the PEDOT: PSS thin film material into a drying oven, drying at 80 DEG C for 10 minutes, treating with concentrated sulfuric acid at room temperature for 12-24hours, washing with deionized water, and finally drying to obtain the high-frequency response porous PEDOT: PSS thin-film material. The supercapacitor prepared from the high-frequency response porousPEDOT: PSS thin-film material has the advantages of high energy density, small internal resistance and good high-frequency responsiveness.

The invention provides a wind power frequency modulation control method suitable for a high wind power penetration level, and relates to the field of wind power generation grid connection, and the method comprises the following steps: monitoring the frequency of a power grid in real time, calculating the instantaneous frequency of the power grid, and when the frequency deviation of the power grid exceeds a set dead zone range due to the disturbance of a power system, measuring the rotating speed of a fan, and when the rotating speed omega r of a fan rotor is larger than the allowable minimum rotating speed omega min, starting a virtual inertia control module of the doubly-fed wind turbine generator, wherein the fan actively participates in frequency modulation; calculating the active increment of the wind turbine generator; calculating the equivalent active power increment of the time domain; calculating an active reference value of the fan; and after the time delta t, gently switching the active power output of the fan to the maximum power tracking output power, so the rotating speed gradually recovers to the initial state. A virtual inertia control link is additionally added to a wind turbine generator rotor side converter controller, when the power grid frequency exceeds the limit due to disturbance, the virtual inertia control link participates in frequency modulation of a power system by use of the rapid throughput of kinetic power of the fan rotor, the frequency modulation response is faster, and the effect is better.

The invention discloses a cobweb-shaped flexible strain sensor capable of identifying a strain direction and a preparation method. The method comprises the following steps of mixing a conductive filler, a hot-melt adhesive and an N, N-dimethylformamide solvent, and carrying out ultrasonic dispersion to obtain a dispersion liquid, putting the granular thermoplastic polymer into a screw extruder, and extruding a pure thermoplastic polymer wire, drawing the wire material to pass through the dispersion liquid at a constant speed by utilizing a wire winding roller traction device, forming a uniformand thin conductive layer on the surface of the wire material, and printing the wire material into a cobweb-shaped array by utilizing a 3D printer after the wire material is completely dried, and fixing the wire at the center of the cobweb and the tail end of the longitudinal wire by using conductive silver adhesive to prepare the cobweb-shaped flexible strain sensor. The cobweb-shaped customizedstructure is rapidly prepared, and the sensor also has the function of identifying the strain direction, has the advantages of high linearity, high sensitivity, wide strain range, rapid response, lowhysteresis, good stability and the like, and has great potential in the application of wearable equipment.

The invention discloses a compensation controller. The compensation controller comprises an operational amplifier, a first resistor, a second resistor, a first capacitor, a second capacitor, a first switch, a second switch and a third switch; the compensation input end is connected with the reverse input end of the operational amplifier after being connected with the first resistor; the positive input end of the operational amplifier is grounded, and the output end is connected with the feedback output end; the first capacitor is connected with the compensation input end and the reverse inputend of the operational amplifier; the first switch and the first capacitor are connected in series; the second resistor, the third switch the second capacitor are connected in series, and then the integral end is connected with the output end of the operational amplifier, and the other end is connected with the reverse input end thereof; and the third switch and the second capacitor are connectedin series and then are connected with the second switch in parallel. The compensation controller is used for an accelerometer closed-loop control system, and the compensation modes can be changed according to different sensitive structures of the accelerometers, so that the system performance is improved, and the system stability is enhanced.

A bus driver circuit divides an internal data bus for an integrated circuit memory into at least two groups, designated by speed. A faster group of data lines and a slower group of data lines are placed in an interleaved fashion in order to provide a two group shielding solution. At the earliest opportunity following the reception of a read command, the data from memory banks in the memory is sorted into these two groups. For a DDR3 memory, the sorting method is based on the A2 column address, known as C2. All of the data is brought out of the banks in parallel and sorted as it enters the main amplifiers. These main amplifiers are also divided into two groups, faster and slower. Each amplifier then connects to a data line (G-line) of the same group. The clock assigned to the fast group fires right away, thereby connecting the data associated with the fast amplifiers to the fast data group. This data group then proceeds to the output buffers through the entire data path as fast as possible. The second, slower data group is started with a delayed clock signal and proceeds through the data path to the output buffer maintaining a fixed delay. Since the first and second data groups are not switching at the same time they act as shields to one another.

The invention discloses a frequency control method based on wind power consumption, comprising the steps as follows: A, calculating a wind power deviation of each sub-area in the control area; B, calculating a total wind power deviation of all sub-areas in the control area; C, distributing the total wind power deviation to each sub-area of the control area to adjust the regional control deviation,and calculating the adjusted regional control deviation after dynamic adjustment of each sub-area; and D, issuing a control command to the generator set in the sub-areas by the automatic power generation control system corresponding to the sub-areas according to the adjusted regional control deviation to realize the frequency modulation control. The invention is capable of sharing the frequency modulation responsibility equally among the sub-areas of the control area to further improve the current state of the frequency regulation of the power grid, so as to achieve the maximum complementaryfrequency modulation capability between the sub-areas, thereby ensuring safe and stable operation of the grid while improving the wind power consumption capacity of the grid.

The invention discloses a carbon nano onion film-based supercapacitor used in the field of alternating current line filtering. An electrode material of a carbon nano onion film with an interconnection structure is synthesized on the surface of a nickel sheet by adopting a chemical vapor deposition method; and a water-based electrolyte or an organic electrolyte is respectively utilized to assemble the carbon nano onion film-based supercapacitor for alternating-current line filtering. According to the carbon nano onion film-based supercapacitor, the advantage of high curvature of the carbon nano onion can be utilized, and the excellent frequency response performance and the high rate performance of the carbon nano onion can be fully exerted. And the super capacitor has high volume specific capacity, volume energy density and good working stability.

The invention relates to a giant dielectric thin film transistor, which is provided with a grid electrode, a semiconductor and a gate insulating layer located between the grid electrode and the semiconductor layer, wherein the gate insulating layer adopts a giant dielectric material; the relative dielectric constant is greater than 10000 at the frequency of 1kHz when the giant dielectric materialis in a ceramic block state, and the relative dielectric constant is greater than 500 at the frequency of 1kHz when the giant dielectric material is in a thin film state; and the giant dielectric material is a non-ferroelectric ceramic material. Compared with a TFT adopting ionic double electric layer to serve as the gate insulating layer, the giant dielectric thin film transistor of the inventionhas the advantage of good frequency response, the frequency response of an inverter is greater than 500Hz, and the circuit is low in consumption, thereby having good application potential in the field of displays. Meanwhile, the giant dielectric thin film transistor of the invention is prepared by adopting the non-ferroelectric material, so that there is no hysteresis phenomenon.

The invention relates to an exhaust valve plate for a compressor. A main body of the exhaust valve plate is of a three-layer composite structure. The three-layer composite structure comprises a firstmetal valve plate layer, a damping layer and a second metal valve plate layer. The damping layer is arranged between the first metal valve plate layer and the second metal valve plate layer in a clamped mode. Compared with metal exhaust valve plates in the prior art, the exhaust valve plate for the compressor adopts the composite structure that the damping layer is clamped between the two metal valve plate layers; an inventor finds that when the metal valve plate layers and the damping layer are combined by adopting a specific thickness and physical parameters, the composite structure can combine the advantages of both metal valve plates and a damping material, the stiffness and flatness required for the exhaust valve plate are reserved, the sealing performance in the compression process is ensured, the frequency response performance of the whole exhaust valve plate can also be improved, a frequency response curve is smoother, and especially vibration and noise when the exhaust valve plate is rebound to a valve seat can be reduced.

The invention discloses a method for optimizing the frequency feedback coefficient of a speed adjuster of a power generator. The method comprises the steps of 1, building a power grid node dynamics model containing the speed adjuster; 2, initializing parameters of a multi-objective particle swarm optimization algorithm; 3, calculating a performance objective function and a sparsity objective function of each particle in a particle swarm; 4, updating a common elite set and a feasible solution elite set; 5, updating a position vector Xpbest of personal guide particles, a position vector Xgbest of global guide particles, wherein the position vector Xpbest and the position vector Xgbest are shown in the descriptions; 6, updating the position and speed of each particle; 7, seeking a particle corresponding to a minimum sparsity objective function J2(Xm(kmax)) in the feasible solution elite set, setting the position vector of the particle as Xm(kmax) to obtain a feedback coefficient matrix Km, namely a final optimization result. By means of the method, the power grid frequency response performance can be improved while the cost price is lowered.