Patents
Literature
Patsnap Copilot is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
Patsnap Copilot

1063results about How to "Inhibition loss" patented technology

Polyphase permanent magnet synchronous motor current waveform optimal control method

ActiveCN103490692AEffective amplitudeEffective Phase Gain ControlElectronic commutation motor controlVector control systemsControl vectorElectric machine
The invention discloses a polyphase permanent magnet synchronous motor current waveform optimal control method, comprising the following steps of A, current reference value coordinate transformation; B, current multiple proportion resonance regulation; and C, coupling compensation. In the control method, based on polyphase permanent magnet synchronous motor vector control, a polyphase synchronous rotating coordinate system current reference value is transformed to a current reference value of each phase in a polyphase static coordinate system through polyphase coordinate transformation, the current reference value of each phase and a current feedback value of each phase of a motor are respectively subjected to improved multiple superposition proportion resonance regulation, and a resonance separation method is introduced, decoupling is realized by feed-forward compensation, and floating tracking and harmful subharmonic restraining for highly dynamic property fundamental waves and usable subharmonic are realized. The method can restrain the adverse impacts, such as motor loss, torque ripple and vibration noise, caused by a harmful harmonic current of the polyphase motor, can explore the positive effects of the usable harmonic current, gives full play to the advantages of the polyphase motor and improves the system performance.
Owner:武汉长海电力推进和化学电源有限公司

STATCOM unbalance compensation control method based on modular multilevel converter

The invention discloses a STATCOM unbalance compensation control method based on a modular multilevel converter (MMC). The method comprises a converter compensation current dead-beat control method and a converter interphase circular current active damping control method. A comprehensive compensation current dead-beat control part is used for compensating active loss in the MMC by controlling active current, reactive current and negative-sequence current which are output by the MMC so as to eliminate unbalance of the current of a power grid and compensate reactive power; the interphase circular current active damping control method is used for summing by detecting the bridge arm current of upper and lower bridge arms of each phase and multiplying by 0.5 to obtain the circular current of each phase, and superposing the output of three-phase current passing through an active damping controller to dead-beat control output so as to inhibit the alternating current component of the circular current, reduce the current stress of converter devices and reduce the loss of the converter. Through the adoption of the method provided by the invention, compensation of the negative-sequence current and reactive current of unbalanced load of the power grid is realized, inhibition of the interphase double frequency circular current of the MMC is simple, the response speed is high and the stability is high.
Owner:HUNAN UNIV

Self-balancing pressure-resistant casing device

The invention discloses a self-balancing pressure-resistant casing device, and belongs to the technical field of a bathyscaphe pressure-resistant structure. The self-balancing pressure-resistant casing device is formed by sequentially sleeving and installing a ball-shaped inner casing, a ball-shaped middle casing and a ball-shaped outer casing around the ball center from inside to outside, wherein the ball-shaped inner casing and the ball-shaped middle casing are connected through a pair of symmetrical and coaxial connecting shaft assemblies; the ball-shaped middle casing and the ball-shaped outer casing are connected through a pair of symmetrical and coaxial connecting shaft assemblies; the axial lines of the two pairs of connecting shaft assemblies are mutually vertical, so that the ball-shaped inner casing and the ball-shaped middle casing can mutually rotate, and the ball-shaped middle casing and the ball-shaped outer casing can mutually rotate; each of the two pairs of connecting shafts is provided with a spring damper; the axial impact between the adjacent casings is resisted. The self-balancing pressure-resistant casing device has the advantages that a control system is simplified; the work reliability and the operation stability of a bathyscaphe are improved; the noise is a cabin is reduced; the work environment comfort of aquanauts is improved; the work safety of the bathyscaphe is improved; the material selective range is expanded; the thickness of the casings is reduced; the processing difficulty of the casings is reduced.
Owner:JIANGSU UNIV OF SCI & TECH

Method for preparing hydrophobic silicon dioxide

The invention relates to one kind of preparation methods of the hydrophobic silicon dioxide using coating, rubber, resin, agricultural chemicals or paper and so on., the characteristic of this method includes the following steps: 1)Select raw materials: according to the principle that the weight of the silicon hydride resin acceptor is 2 -20% of the water affinity silicon dioxide to select the silicon hydride resin acceptor and the water affinity silicon dioxide; 2)Mixing the silicon hydride resin acceptor and the O / W emulsion sparse hydration medicinal preparation below 0 degree C to 40 degree C, making the O / W emulsion sparse hydration medicinal preparation whose surface absorbs hydrolyze substance of the silicon hydride resin acceptor; 3)Contacting the O / W emulsion sparse hydration medicinal preparation made by the second step, with the surface absorbing hydrolyze substance with the water affinity silicon dioxide, and carrying on heat treatment for the mixture of the water affinity silicon dioxide and the O / W emulsion sparse hydration medicinal preparation, the process's temperature is 100 degree C to 130 degree C, the process's time is 20 to 100 minutes, gain the hydrophobic silicon dioxide. The hydrophobic silicon dioxide made by this invention has the high hydrophobic characteristic.
Owner:WUHAN UNIV OF TECH

Strawberry preservative containing functional amino acids

The invention provides a strawberry preservative containing functional amino acids. The strawberry preservative is characterized in that the strawberry preservative comprises 0.2-0.5g/L of gamma-aminobutyric acid, 0.3-0.5g/L of arginine, 5.0-10.0g/L of ascorbic acid, 7.5-10.0g/L of calcium chloride, 5.0-10.0g/L of acetic acid, 10.0g/L of chitosan, and the balance distilled water. The preparation method of the strawberry preservative comprises the following steps: dissolving ascorbic acid and acetic acid in distilled water, adding chitosan to the obtained solution, dissolving, uniformly mixing, and sequentially adding gamma-aminobutyric acid, arginine and calcium chloride. The strawberry preservative can substantially reduce the rotting rate of fruits and prolong the storage period and the shelf life of strawberries when the strawberry preservative is used for the preservation and fresh keeping treatment of the strawberries. Additionally, the ingredients of the preservative contain a proper amount of a food additive and are rich in the functional amino acids which comprise arginine and gamma-aminobutyric acid and have nutrition and healthcare effects on human bodies, so there is no toxicity residual, and the nutrition and healthcare effects of fruits and vegetables to the human bodies can be enhanced, thereby the preservative accords with the current preservative development direction and has a good exploitation application potential.
Owner:SHANDONG UNIV OF TECH

Short-circuit fault-tolerant vector control method for embedded hybrid magnetic material fault-tolerant cylindrical linear motor

The invention discloses a short-circuit fault-tolerant vector control method for an embedded hybrid magnetic material fault-tolerant cylindrical linear motor. The short-circuit fault-tolerant vector control method comprises the following steps: building a five-phase embedded hybrid magnetic material fault-tolerant cylindrical linear motor model; compensating normal thrust missing caused by a short-circuit fault phase and suppressing a thrust ripple caused by phase short-circuit current with non-fault phase current of the motor; and obtaining expected phase voltage by adopting a series of coordinate conversion and voltage feed-forward compensation strategies, and achieving a fault-tolerant vector control after the phase short-circuit fault of the motor by a zero-sequence voltage harmonic injection-based CPWM modulation mode. According to the short-circuit fault-tolerant vector control method, the motor can suppress the thrust ripple of the motor under the condition of a phase short-circuit fault-tolerant operation; more importantly, the dynamic property, the steady-state performance and the properties in a normal state are consistent; the switching frequency of a voltage source inverter is constant; a CPU is low in overhead; and a natural coordinate system only needs to counterclockwise rotate a certain angle in any phase short-circuit fault, so that the motor fault-tolerant operation can be achieved.
Owner:JIANGSU UNIV

Essence particle additive as well as preparation method and application thereof

The invention discloses an essence particle additive as well as a preparation method and an application thereof. The particle additive consists of a particle carrier, cigarette essence and a polymeric membrane, wherein the particle carrier is used for loading the cigarette essence, and the polymeric membrane is used for coating the particle carrier loaded with the cigarette essence; the particle carrier is composed of calcium carbonate particles, a molecular sieve, tea dust, microcrystalline cellulose or cellulose microspheres; the cigarette essence is isoamyl alcohol, phenethyl alcohol, menthol, linalool, terpinol or limonene; and the polymeric membrane is prepared from sodium alginate tech grade, carboxymethyl cellulose, hydroxyethyl cellulose or pullulan. According to the physical form of the cigarette essence, the essence particle additive can be prepared by a liquid-state method and a solid-state method. When being applied to the flavoring of a cigarette filter and the production of a cigarette, the essence particle additive has the beneficial effects that when the cigarette is not sucked, the volatilization and diffusion of the essence are restrained, and when the cigarette is sucked, the essence can be uniformly released without the dependence on external forces.
Owner:CHINA TOBACCO CHUANYU IND

Orchard grass intercropping method

The invention relates to the technical field of agriculture, and provides an orchard grass intercropping method. The method comprises the following steps: zones are divided, wherein grass is planted between orchard lines, and straws are laid within a range of 0.5m from tree trunks; plowing is carried out, wherein an EM inoculant is spread to grass planting zone soil, and plowing is carried out after 20-30 days; seed soaking is carried out, wherein grass seeds are soaked with the EM inoculant for 4-12h, and are air-dried at a shaded and ventilated place; sowing is carried out, wherein a sprinkler irrigation treatment is carried out with a diluted composite bacterial fertilizer, and uniform sowing is carried out with a sowing amount of 12-15kg/Mu when the soil is moist; management is carried out, wherein watering is carried out after sowing, and sprinkler irrigation is carried out with a diluted EM inoculant when seedlings uniformly shoot; and maintenance is carried out, wherein a grass height is maintained at 10-20cm, and a mixture of trimmed-off grass and straws is laid within a range of a tree base. The method has water-retaining, fertilizer-retaining and drought-resisting functions. With the method, farm chemical is not applied, and the effect of green manure is good. Chemical fertilizer is saved, and disease degree can be reduced from the source. Soil salinization can be effectively ameliorated, and fruits can be green and organic.
Owner:北京百丰生物科技集团有限公司

Degradable liquid mulching film and production method thereof

The invention relates to a degradable liquid mulching film and a production method thereof, particularly to an environment-friendly degradable liquid mulching film with straws as a basic raw material and a production method thereof. The degradable liquid mulching film is prepared from steaming slurry of crop straws (such as wheat straws, rice straws, cotton straws, wood shavings, and the like) or straws paper-making black liquor as a main raw material by a series of reactions, such as sulfonation, crosslinking and copolymerization, of macromolecules in the slurry or the black liquor, such as lignin, cellulose and polysaccharides, under the action of a film formation additive. The macromolecules in the degradable liquid mulching film have a large amount of hydrophilic groups which can effectively catch the water molecules evaporated and diffused from soil to the air, so as to prevent water evaporation and heat loss arising therefrom, thereby increasing the temperature and preserving soil moisture. The degradable liquid mulching film is helpful for increasing crop yield and improving crop quality; and the yield is higher than that by use of a plastic mulching film, and the per mu yield is increased by more than 5%. The degradable liquid mulching film can replace the conventionally used plastic mulching film.
Owner:SHANDONG SI DA KE BIODEGRADABLE TECH CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products