154results about How to "Guaranteed inhibitory effect" patented technology

The invention discloses a non-isolation type three-phase three-level V2G charge-discharge topological structure. The non-isolation type three-phase three-level V2G charge-discharge topological structure comprises a main circuit module and a control circuit module, wherein the main circuit module comprises three parts in cascading manner, including a DC/DC part, an H bridge balance circuit and a DC/AC part; a vehicle-mounted power battery is connected to a direct current positive bus and a direct current negative bus through a bidirectional half-bridge converter; the H bridge balance circuit and two voltage-division capacitors C1 and C2 are arranged between the direct current positive bus and the direct current negative bus, and the direct current positive bus and the direct current negative bus are connected with the output end of the bidirectional half-bridge converter in parallel; the direct current buses are connected with a diode clamping type three-level PWM converter; a three-phase alternating current power supply live wire is connected to connecting places of upper and lower bridge arms of each phase of the bridge arms through a three-phase LC filter; the direct current buses are positioned in the H bridge balance circuit; according to the H bridge balance circuit, an IGBT switch tube Tb1 is in anti-parallel connection with a rapid recovery diode, or the switch tube Tb1 with an in-vivo parasitic diode is connected with a one-way conducive free-wheeling diode Db1 in series to form one side bridge arm, and a balance inductor Lb1 is connected in the middle thereof; the other end of the balance inductor is connected to a direct current side middle point; the bridge arms on the two sides are connected with a shared negative electrode and a shared positive electrode; and namely, the upper ends of the bridge arms are both connected to the direct current positive bus while the lower ends of the bridge arms are both connected to the direct current negative bus.

The invention discloses a hydraulic pipeline fluid pulse active inhibition method based on a bilateral overflow principle. The method utilizes a piezoelectric ceramic direct drive type four-way slide valve as an executive component of fluid pulse active control, A and B ports of the slide valve are connected to same side branch of a hydraulic pipeline, and P and T ports of the slide valve are connected with an oil box; and a sine control signal drives the slide valve to finish a periodic motion process, the A and B ports realize twice overflowing through the P and T ports, namely bilateral overflowing, and the generated overflowing flow can completely counteract source pulse flow, thereby realizing the active inhibition of hydraulic pipeline fluid pulse. The active inhibition method provided by the invention has the advantages that (1) the motion frequency of the slide valve is one half of the flow pulse frequency of a hydraulic system to be eliminated; and (2) maximal overflowing flow can achieve the flow of the slide valve when a piezoelectric ceramics actuator is in maximum elongation quantity. The invention provides the fluid pulse active inhibition method for the hydraulic system which has the advantages of high speed, high pressure and high power density, and the fluid pulse active inhibition method is further easily practical.

The invention provides a mechanical arm impedance control method. A position-based impedance control method and a force-based impedance control method are fused; a joint position controller is arranged in the mechanical arm; the control architecture of an admittance controller combined with the inverse kinematics of the mechanical arm in the position-based impedance control method is replaced by the control architecture of a virtual impedance controller combined with a forward dynamics solver, an impedance controller in the force-based impedance control system is replaced by a control loop, sothat a reference impedance force Fimp obtained by a pose error of a Cartesian space through a reference impedance model is converged to an actually measured external force Fs, and then an FFC is output through a closed-loop force controller. According to the method, the control precision and the stability during interaction with the hard environment are ensured simultaneously in mechanical arm impedance control, and a new method is provided for motion control of the industrial mechanical arm.

The invention discloses a method for planting corn and cover crops, belongs to the field of crop planting, and particularly relates to a cultivating method of inter-annual crop rotation of corn and the cover crops. The technical problems of reduction of soil quality and non-point source pollution caused by large-scale use of chemical fertilizers, pesticides and herbicides in the corn planting process are solved. The cultivating method comprises the steps of 1, soil preparation in spring, 2, ridging and basal dressing, 3, sowing of corn, 4, sowing of the cover crops on ridges, 5, planting of the cover crops in furrows, 6, harvest of corn, 7, crushing of residual bodies of the cover crops and plowing in the spring of a next year, 8, ridging in the next year, and 9, field management in a second year. The cover crops such as gramineae are planted in the furrows, so that the field space is fully used, and the growth of weeds is avoided. The cover crops such as gramineae are planted in the furrows the biological yield is high, the absorption and utilization capacity for N in deeper layers of soil are good, and the protection effect for water resources and ecological environment is good.

The invention discloses a flexible satellite active vibration suppression method based on component force synthesis and fixed time convergence. The flexible satellite active vibration suppression method comprises the following steps of step 1, establishing a flexible satellite attitude dynamics model with two pairs of large solar panels, and simultaneously establishing a dynamic model of a piezoelectric intelligent material actuator; step 2, designing a fixed time convergence sliding mold controller; step 3, designing a disturbance observer for ensuring a double-layer self-adaptive law with fixed time convergence characteristics; and step 4, outputting a dynamic model of the piezoelectric intelligent material actuator, implementing processing by adopting a continuous component force synthesis control idea, generating a new control torque command to be applied to a flexible accessory to counteract the influence of elastic vibration, and ensuring the attitude stability of a satellite body. The flexible satellite active vibration suppression method has the advantages of high attitude control precision and strong robustness. Meanwhile, a continuous component force synthesis method is introduced into a closed-loop control process through a piezoelectric sheet attached to the flexible accessory, vibration is inhibited, and the system interference is reduced.

The invention discloses a compensation method for magnetic resonance gradient eddy current, the method is as follows: a plurality of reverse overswing modules with independent adjustable time parameter and range parameter are formed on the common gradient waveform generator; and a switching switch is added in each gradient channel for switching the each gradient channel at the main coil mode, shielding coil mode and common mode; then, adjusting the parameter for each gradient channel under the main coil mode and the shielding coil mode; finally, recovering all gradient channels to the common mode, adopting the algorithm optimization for optimizing pre-emphasis parameter and reverse overswing parameter; the method can improve the inhibitory effect of short time component of eddy current field while combining the pre-emphasis technology and self-shielding technology and keep the inhibitory effect of long time component of eddy current field.

The invention discloses a lithium nickel cobalt manganate/lithium nickel cobalt aluminate battery and a functional diaphragm for the lithium nickel cobalt manganite/lithium nickel cobalt aluminate battery as well as a production technology of the diaphragm and belongs to the technical field of battery diaphragms. The lithium nickel cobalt manganite/lithium nickel cobalt aluminate battery disclosedby the invention comprises a porous diaphragm base material and a functional coating layer which coats the surface of the base material; coating of the functional coating layer comprises a filling agent, an adhesive, a thickening agent, a dispersant and a stabilizer, wherein the stabilizer is selected from one or more of a combination of triethylenetetramine hexaacetic acid, diethylenetriamine pentaacetic acid, 1,3-diamino-2-hydroxypropane-N,N,N',N'-tetracetic acid, N,N-bi(2-hydroxyphenyl)ethylenediamine-N,N-diethylamine hydrochloride and dihydroxyethylglycine. By adopting the technical scheme provided by the invention, the shuttling of nickel, cobalt, manganese and aluminum metal elements can be effectively inhibited, so that the circulating performance of lithium nickel cobalt manganiteand lithium nickel cobalt aluminate ternary batteries is improved.

The invention discloses a compact full-balance type broadband filtering power divider which is of a central symmetry structure. Two cascaded three-wire coupling microstrip lines of which the two endsare loaded with chip capacitors and the wavelength is one eighth of that of the chip capacitors and a three-wire coupling microstrip line of which the wavelength is one fourth of that of the chip capacitors are arranged on a top metal layer. A central connection point is arranged between the middle microstrip line and the outer microstrip line of the quarter-wavelength three-wire coupling microstrip lines. Two grooves are formed in the metal ground, two metal patches and an isolation resistor connected with the two metal patches are arranged in the grooves respectively, and the four metal patches are connected with the outer microstrip lines of the two three-wire coupling microstrip lines with the one-eighth wavelength in a one-to-one correspondence mode through plated-through holes respectively. By cascading two three-wire coupling microstrip lines with one eighth wavelength and one three-wire coupling microstrip line with one quarter wavelength and combining the plurality of chip loading capacitors and resistors, the full-balanced broadband filtering power divider with the characteristics of small size, wide frequency band and low loss is obtained.

The invention relates to a Ka frequency range miniaturization broadband multimode auto-tracking feed source network. Two polarization degenerate modes of TE21 mode transmitted by center circular waveguide are coupled to four rectangular waveguide by adopting a four-arm circular polarization TE21 coupler. Two four-way polarization degenerate modes of the TE21 mode is combined into two two-way polarization degenerate modes of the TE21 mode by two broadband magic Ts. A left-handed or right-handed circular polarization difference mode is output by a broadband 90-degree electrical bridge. The TE21 coupler center circular waveguide is capable of simultaneously transmitting a TE11 mode. Due to the fact that the TE21 coupler is connected with a broadband circular polarization machine, and two polarization modes of a signal are respectively output from two ports of the broadband circular polarization machine, the Ka frequency range miniaturization broadband multimode auto-tracking feed source network is capable of simultaneously receiving a signal of double-circular polarization and a difference signal, and thereby the auto-tracking function is realized. The Ka frequency range miniaturization broadband multimode auto-tracking feed source network has the advantages of not only simplifying composition of the feed source network, reducing the volume and the weight of the whole device, but also reducing network construction, saving feed source cost and broadening working band of the feed source network.

The invention discloses a double-codebook multi-user multiple-input multiple-output (MU-MIMO) precoding method based on Schmidt orthonormalization, and belongs to the communication field. The precoding method includes the following steps: (1) constructing a codebook I according to the Grossmann space packing principle, then constructing a codebook II according to the Schmidt orthonormalization principle and considering the chordal distance between vectors, and storing the two codebooks together in a base station end and a mobile station, (2) carrying out channel estimation according to pilot signals sent by a base station, then going through precoding vectors in the codebook I, selecting out best matching code words, and sending indexes and corresponding signal interference plus noise ratio (SINR) values of the code words to the base station as feedback, (3) the base station ensuring a present precoding matrix in the codebook II according to the collected feedback information, and carrying out user scheduling on the basis. Through adoption of the method, an expanded space of the codebooks are enabled to be larger, moreover orthogonal property of the precoding matrix is guaranteed, and restraining capacity to color contribution index (CCI) is ensured. Meanwhile, the user scheduling scheme of the base station end enables the failure phenomenon of user matching not to exist.

The invention discloses a method and device for setting the critical gain of a power system stabilizer. The method comprises steps of constructing an electromechanical transient model for the single-machine infinite system of a generator to be tested; performing simulation by using electromechanical transient model according to a preset gain step from the preset initial gain of the power system stabilizer of the generator to be tested, so as to obtain the root trajectory of an excitation oscillation mode; according to a preset critical damping ratio threshold, processing the root trajectory ofthe excitation oscillation mode so as to obtain the critical gain of the power system stabilizer; inputting the critical gain of the power system stabilizer to the electromechanical transient model,performing time-domain simulation verification of a terminal voltage step so as to set the critical gain of the power system stabilizer of the generator to be tested. The method can reduce the actually measured error of the critical gain, set the gain value of the power system stabilizer, and further ensures the safe and stable operation of the power system.

The invention discloses an LLCL filter with an LRC (Longitudinal Redundancy Check) parallel passive damping circuit. A parallel damping circuit (7) is in tandem connection between a connection joint (3) of a bridge arm inductance (L1) and a grid-side inductance (L2) and a parallel resonance branch circuit; the parallel damping circuit (7) is formed by a damping resistor (Rd), a damped inductance (Ld) and a damping capacitor (Cd) which are in parallel connection; the LC resonance frequency of the parallel damping circuit is identical to that of the LLCL filter; two ends of the LLCL filter are provided with an inverter (1) bridge arm lateral output terminal (2) and a grid (3) terminal (4) after the bridge arm inductance (L1) and the grid-side inductance (L2) are in tandem connection; a series resonance branch circuit which is formed by an additional inductance (Lf) and a filter capacitor (Cf) is in bridge joint between the connection joint (3) and a common terminal (6) of the inverter (1) and the power grid (5). The LLCL filter with the LRC parallel passive damping circuit in a large-power grid-connected inverter can meanwhile satisfy the high-frequency filter effect, the damping loss and the system stability.

The invention relates to a gel product instant-dissolving novel dosage, and in particular relates to a gel product instant-dissolving block and a preparation method of the gel product instant-dissolving block. The preparation method comprises the following steps: adding water into a raw material so that the raw material is dissolved, and carrying out concentrating to obtain a gel solution; carrying out drying treatment on the gel solution, thus obtaining an irregular cellular gel body; grinding the gel body, and carrying out screening to obtain gel powder with the partical size not being smaller than 80 meshes; and wetting the gel powder by adopting 85-95 % alcohol, and carrying out compressing according to the compression ratio of 30%-60% for obtaining a block, wherein the obtained pressed block is the gel product instant-dissolving block. The gel product instant-dissolving block provided by the invention has the loose pore structure inside, has high superficial area/volume ratio, hasthe product density being 0.4-0.8 g/cm<3>, and can rapidly dissolve within 2min in hot water, in addition, the gel product instant-dissolving block is crisp in mouthfeel and can be directly orally administrated, and thus the convenient taking demand of consumers under different conditions can be satisfied.

The invention discloses a preparation method of a shale inhibitor with a filtrate reduction property. The method comprises the following steps: (1) adding an inorganic base to an n-amine solution, and uniformly mixing and stirring the inorganic base and the n-amine solution, wherein n is an integer larger than 1, the dosage of the inorganic base is 0.05-3% of the mass of the n-amine, preferably 0.5-1%; (2) adding an etherifying agent to the mixed fluid of the step (1), carrying out a reaction under 60-100 DEG C for 6-10 hours, preferably under 80-100 DEG C for 8-10 hours, the molar ratio of the etherifying agent to the n-amine is larger than 1.0, preferably 2.0-4.0; (3) reducing the temperature to indoor temperature after the reaction in the step (2) is over, and regulating the pH value of the solution to the neutral value so as to obtain the shale inhibitor with the filtrate reduction property. The preparation method is simple in preparation process and low in cost, the prepared shale inhibitor has good performance of shale inhibition and good filtrate reduction property at the same time, requirements for the performances of the shale inhibitor and a filtrate reducer which are used for a drilling fluid can be satisfied at the same time, one agent integrates multiple functions, and therefore, the actual problems of hydration, dispersion and swelling of clay shales, the collapse of a borehole wall, and the like can be solved.

The invention relates to a use of supersonic wave in sewage treatment biological denitrification. A short-distance nitration process is stimulated by supersonic wave so that sewage is subjected to high efficiency denitrification. The short-distance nitration comprises that in a microbe nitration reaction, ammonia nitrogen is oxidized into nitrite and nitrate is not produced A supersonic generator probe is arranged in an aeration tank of an activated sludge process-based sewage treatment system or is connected in a sludge return pipe in series so that the short-distance nitration is stably realized by a bioreactor. The microbe screening characteristics of supersonic wave realizes stimulation of activity of nitrite bacteria and inhibits activity of nitrite bacteria. Supersonic wave is convenient for operation, has stable effects and has a wide application prospect in a sewage treatment biological denitrification technology.

The invention discloses a high-performance lithium-sulfur battery diaphragm and a preparation method and application thereof, and belongs to the technical field of battery diaphragms. The high-performance lithium-sulfur battery diaphragm comprises a porous diaphragm matrix, and the porous diaphragm matrix is prepared from the following raw materials in percentage by mass: 20-40% of polyethylene, 0.5-10% of carbon nanotubes and 0.5-10% of conductive carbon black and/or graphene. The preparation process of the diaphragm comprises the following steps: blending and modifying polyethylene, carbon nanotubes and conductive carbon black and/or graphene through an extruder, and carrying out two-way stretching and extraction to prepare a honeycomb-shaped porous diaphragm matrix; and coating or compounding the surface of the porous diaphragm matrix with an inorganic nano ceramic layer to obtain the high-performance lithium-sulfur battery diaphragm. By adopting the technical scheme provided by theinvention, the shuttle effect of lithium polysulfide of the lithium-sulfur battery can be inhibited, and the use performance of the lithium-sulfur battery can be improved.

The invention discloses a multichannel low noise amplifier. The multichannel low noise amplifier comprises an LNA body, a second-level amplifier, a first duplexer, a low-frequency-band filter, a high-frequency-band filter, a second duplexer and a third-level amplifier, wherein the LNA body, the second-level amplifier and the first duplexer are connected in sequence, the output end of the first duplexer is divided into two branches, one branch is connected with the low-frequency-band filter, the other branch is connected with the high-frequency-band filter, the output end of the low-frequency-band and the output end of the high-frequency-band filter are combined to be connected to the second duplexer, and the output end of the second duplexer is connected with the third-level amplifier. According to the multichannel low noise amplifier, three-level amplification is achieved so that the gain of a signal can be high enough, the signal is divided into branches to be processed, multiple channels are achieved, out-of-band rejection of each branch of signal is guaranteed through a corresponding filter, the structure is simple, and performance is stable.

The invention discloses an optimal delay compensation method for active damping of an LCL-type converter. The method includes determining the delay time of a system to acquire an active damping control model; simplifying the active damping control model, and calculating the virtual impedance generated by an inner loop delay to acquire a resonance peak and the reason why the resonance frequency isaffected by the delay; from the perspective of resonance inhibition, determining the optimal compensation method: feedback coefficients plus lead phase compensation; designing a lead compensation device, determining the feedback coefficients, comparing the ideal and the corrected amplitude-frequency response figures, and verifying the optimality to acquire the optimal amplitude-frequency responsefigures. The optimal delay compensation method has the advantages that resonance frequency shifting and resonance peak amplification both caused by the delay during the active damping control can be suppressed, the stability margin of the system is improved, and the attenuation ability of the LCL to high-frequency harmonic waves and the high anti-interference ability to the grid-side impedance fluctuations are guaranteed.