209 results about "Winding loss" patented technology

Cutout and/or keep away regions are etched in the winding structure near the gapped center leg of a magnetic core. This reduces eddy current losses caused by the leakage field and improves current uniformity and current sharing between windings thereby increasing converter efficiency. Windings closest to the air gap are suitably formed with both keep away regions and cutouts. Windings a little further away are formed with only cutouts and the windings furthest away are unchanged. This approach keeps the net winding losses low in the presence of a fringing field. The precise configuration is determined by the core structure, air gap and winding arrangements.

The invention relates to a large grid real-time scheduling method for accepting access of wind power, which belongs to the technical field of power system operation and control. The method comprises: according to the characteristics of wind power and load fluctuation and the control characteristics of generator sets, classifying the generator sets in the whole grid; acquiring the current plan, real-time output, connecting line plan, numerical weather prediction and other related information of each generator set; performing ultrashort period load prediction and wind power output prediction towork out the output regulation amount at next moment of real-time scheduling generator sets and construct an active real-time scheduling model with the smallest wind loss; working out the output regulation amount of the real-time scheduling generator sets including the wind power generator sets by using a simplex method; and transmitting the next output regulation amount of thermal power generator sets directly, and giving the output maximum value at next moment of the wind power generator sets. In the invention, the combined optimized scheduling of the wind power generator sets and traditional generator sets is performed to eliminate wind power generation prediction deviation and load prediction deviation in advance, so the wind power accepting capability of a power grid is improved to the maximum extent while the operation economy of the power grid is guaranteed.

This invention discloses an oil and smoke filtering device which includes at least two filtering pans that set vent holes. The holes on the border filtering pans set alternatively. Its character is in that the around of the vent holes has turned-over edge which faces the inside of the ventilator. It has such merits as good filtering effect, low wind loss, low noise, long non-maintain time which especially fits to the oil and smoke ventilator.

A solid dust suppressant is prepared by mixing 40-90% of a water-soluble high molecular polymer, 5-40% of water-soluble high molecular glue, 0-25% of a moisture absorption humectant, 0.5-5% of a flexibilizer, 1-5% of an antiseptic and 3-10% of an osmotic agent, and has the characteristics of high film forming strength, low brightness and moderate viscosity. The viscosity (at 25DEG C), the pH value, the wind loss rate (under 30mm/s wind speed 5mins, %), the cured layer thickness, the film tensile strength, the film elongation at break and the material bursting strength of the solid dust suppressant are not lower than 8.0mPa.s, 6.0-7.0, not greater than 0.40, not lower than 11.25mm, greater than 11mpa, greater than 13% and greater than 0.05mpa respectively, and the solid dust suppressant realizes difficult brittle rupture after film formation, has a long effective dust suppression time and an ideal dust suppression effect.

Computer-implemented methods of estimating insurance risk of one or more structures are described. The computer-implemented methods may be based on a combination of tree characteristic information and insurance loss data that are used together to calculate a Tree Proximity Score for the one or more structures through a computer processor. The tree characteristic information may include vegetation density data, tree height, tree geometric characteristics, and tree species information, and may be based on tree sensor data which may include satellite imagery, aerial imagery, or LiDAR. The insurance loss data may include wind loss data such as a wind loss frequency, severity, or ratio. The high level of correlation between the Tree Proximity Score and insurance loss data is shown in an example. The Tree Proximity Score may be used in the insurance industry in insurance policy implementation and underwriting.

A matrix transformer particularly suited to large voltage step-down, high current applications achieves increased good current sharing uniformity or air gap and electrical characteristics and reduced or eliminating termination losses, core losses and winding losses with a unitary magnetic core structure featuring sheets of magnetic material and a two-dimensional array of pillars on which windings, oriented in opposite directions on pillars that are adjacent in orthogonal directions, can be formed or placed comprising metallization on or embedded in a printed circuit board (PCB) structure. Magnetic flux density is reduced by at least one-half by dividing the magnetic flux in each pillar into two paths of increased width in the sheets of magnetic material. Magnetic flux density may be further decreased and flux uniformity improved by extending the sheets of magnetic material beyond a periphery defined by the pillar array.

The invention discloses an axial flux motor of a stator iron-core-free Halbach permanent magnet array. The motor includes two permanent magnet rotors, the rotors are mounted on a rotating shaft in the manner that permanent magnets of the rotors face each other, and a circular ring made of a high-molecular material is mounted between the rotors; radial guide grooves are regularly arranged in the circumferential directions of the front and back sides of the circular ring, and used for mount a stator winding coil with excitation lines; each permanent magnet rotor is composed of a magnetic conductive yoke of the rotor and a segmented permanent magnet mounted in the yoke; and 12 permanent magnets whose magnetizing directions are different from one another are mounted under each pair of poles, the axial magnetizing direction of the first permanent magnet is 0 degree, the difference between the magnetizing directions of the adjacent permanent magnets is 30 degree, and, thus, the Halbach array is realized, and the content of harmonic waves of air-gap flux density is greatly reduced. The axial flux motor has the advantages of high air-gap flux density sine degree, low winding loss, high structural intensity of the stator, good heat radiation effect, and high power/volume ratio.

The invention discloses a method for quickly discharging for an automobile high-voltage DC bus, comprising a main motor system and a plurality of electro-subsystems, wherein the main motor system is connected with the DC bus, the electro-subsystems are also connected with the DC bus and are connected with the main motor system in parallel, and each subsystem is driven by the motor. The invention also comprises a discharge resistor connected with the DC bus in parallel. The method comprises the following steps: (1) when the DC bus is in outage, the main motor serves as a first motor for controlling; a first motor controller sends a signal to the first motor; the first motor generates current to cause a motor winding to heat to dissipate capacitor voltage on the DC bus; and (2) when the first motor can not normally operate, the discharge resistor dissipates the capacitor voltage on the DC bus. On the premise of not influencing the automobile running state, the invention only uses motor winding loss to quickly dissipate electricity energy stored in each subsystem filter capacitor on the high-voltage DC bus; and no discharge resistor is required to be connected in parallel in each subsystem controller, thus improving system efficiency and lowering part cost. The invention can quickly discharge to capacitors connected on the high-voltage DC bus in parallel after cutting off high voltage; then, strong electricity and week electricity are almost synchronous during parking so as to simplify finished automobile control algorithm; and specially, passenger safety can be effectively ensured during emergency failure.

The invention belongs to the field of inductor design, and particularly relates to a high-frequency eddy current effect-considered semi-analytical calculation method for winding loss. The method comprises the following steps of: obtaining a complex permeability expression of a single isolated circular conductor in a uniform time-harmonic magnetic field; calculating complex permeability of homogenization of a multi-turn circular conductor coil; metering influences which consider a skin effect through importing an impedance corresponding to the skin effect; establishing a two-dimensional finiteelement model, and calculating magnetic field intensity of a space region so as to obtain magnetic field intensity of a conductor region and an air region; calculating total magnetic field energy eddycurrent loss stored by the conductor region and the air region by combining the magnetic field intensity, obtained via static magnetic field finite element simulation, of the conductor region and theair region; and calculating eddy current loss of a multi-turn conductor region, and summating skin effect eddy current loss and proximity effect loss to obtain total loss of a winding region. The method can be used for determining winding loss of multi-turn conductor coils and effectively decreasing the calculation workload, and is beneficial for engineering application.

The invention discloses a temperature field calculation method of a reactor based on multi-physical field coupling. Firstly, a three-dimensional simulation model of the reactor is established. Subsequently, based on the electromagnetic theory of field-circuit coupling, the current of each layer of reactor is calculated by the finite element method, and the winding loss of each layer is calculated,then the thermal density per unit volume of reactor is calculated. Finally, based on fluid-temperature coupling, the finite volume method is used to solve the temperature distribution of the reactorwith the unit volume heat density of the reactor as the heat source parameter. The temperature field distribution of the reactor calculated by the invention provides a theoretical basis for structuralperformance optimization of the reactor and online monitoring of the temperature.

The invention discloses a method for directly measuring the winding loss of a magnetic component, wherein the magnetic component includes a magnetic core and a winding. According to the method, an auxiliary winding is additionally wound on the magnetic core of the magnetic component; the auxiliary winding is open-circuited; an excitation source is applied to the magnetic component; a voltage relation between the port of the measured winding and the port of the auxiliary winding of the magnetic component, and current passing through the measured winding are measured through a measuring instrument; voltage between the ports is calculated, so that the voltage the lost of the measured winding can be obtained; and the power of the measured winding is obtained through calculation, and the power of the measured winding is the loss of the measured winding. The method of the invention is suitable for measuring the winding loss of any magnetic component under any excitation waveform condition and is also used for measuring the winding loss of a magnetic component in a power converter online. The method can embody influences on winding loss caused by a magnetic field, temperature and actual working conditions in a magnetic component and can also measure the loss of each winding of a multi-winding magnetic component. With the method adopted, winding loss can be separated from total loss. The method has the advantages of convenient measurement, quickness and low cost.

The invention discloses a printing press dry box comprising an air inlet arranged on the side wall of the dry box, and an air outlet arranged on a dry box top cover, multiple blast nozzles are arranged on the positions, horizontal to the air inlet, in the dry box, the blast nozzles directly face substrates on a guide roll assembly, multiple return ducts are arranged on a middle baffle of the dry box, the exits of the return ducts face towards the dry box top cover. The design of the dry box is reasonable, the V-shaped blast nozzles directly face the substrates on the guide roll assembly, so that the air circulation in the dry box can be guaranteed to be smooth, the heat wind loss is reduced, the energy saving is realized, clear patterns of presswork can be guaranteed, and the printing ink transfer is uniform.

A transformer assembly. In some embodiments, the transformer assembly comprises a transformer, comprising a magnetic core; a primary winding wound around the magnetic core, wherein the primary winding comprises one or two turns of a first conductive material; and a secondary winding wound around the magnetic core, wherein the secondary winding comprises a plurality of turns of a second conductive material, and wherein a diameter of the magnetic core is sized such that the transformer achieves a first inductance with a core loss comparable to a winding loss.

The invention discloses a multi-angle multi-surface multi-layer 360-degree air-supplying sinter ore cooling tower and belongs to the technical field of sintering equipment for iron making. The multi-angle multi-surface multi-layer 360-degree air-supplying sinter ore cooling tower is used for cooling sinter ores and recycling heat energy and consists of a feeding skew bridge, a distribution dust and waste air collection chamber, a dust collecting pipeline, a distributing device, a high-temperature heat energy recycling system, a boiler circulating air reutilization system, a medium-temperature cooling recycling system, a low-temperature cooling system and an unloading system. The sinter ores are uniformly packed into the cooling tower via the feeding skew bridge by a distributor; the high-temperature heat energy recycling system is used for sending utilizable hot air to a boiler; circulating air of the boiler is returned to a high-temperature section of the boiler by the boiler circulating air reutilization system so as to cool the sinter ores; cooling fans are uniformly mounted at a low-temperature section in the cooling tower in a layered way so as to cool the sinter ores; air vents and ventilating pipelines are respectively arranged at a medium-temperature section and the low-temperature section to realize flowing of cooling air inside the tower so that the sinter ores can be cooled. The multi-angle multi-surface multi-layer 360-degree air-supplying sinter ore cooling tower disclosed by the invention has the characteristics of being small in floor area, near in wind run, free of wind loss, high in wind utilization rate, high in heat energy collection rate, good in cooling effect and free of dust diffusion.

The embodiment of the invention discloses a consequent-pole permanent magnet biased bearingless doubly salient motor and a control method thereof, and relates to the technical field of a bearingless motor. The problems of winding loss and heat generation imbalance can be solved; the motor reliability is improved. The consequent-pole permanent magnet biased bearingless doubly salient motor is characterized in that iron cores of a stator/rotor are respectively of a salient pole structure; a groove is formed from a position, facing the surface middle position of an air gap (11), of each stator pole 1-1 to the edge position of the stator pole 1-1 in the anticlockwise direction; a permanent magnet is pasted in each groove; the polarities of the surface of each permanent magnet facing the air gap (11) are identical; an armature coil is wound on each stator electrode 1-1; each armature coil is sequentially connected in series to form an armature winding; each armature winding is respectivelyconnected with an external main circuit; every three stator poles 1-1 are wound with a suspension coil; the spatially and radially opposite suspension coils are connected in series to form a suspension winding and are connected with an external suspension control circuit. The consequent-pole permanent magnet biased bearingless doubly salient motor and the control method are applicable to high-speed application occasions of aerospace electric driving systems and the like.

The invention relates to a wireless power transmission magnetic coupling system structure parameter optimization method based on SSP compensation. The method includes: establishing an electromagneticfield calculation model of the single-turn planar spiral coil; obtaining the coupling coefficient of the single-turn planar spiral coil model and the single-turn average inductance of the transmittingcoil and the receiving coil by taking the maximum coupling coefficient between the transmitting coil and the receiving coil as a target; establishing a multi-turn coil magnetic coupling system simulation model to obtain a coupling coefficient and single-turn average inductance of the transmitting coil and the receiving coil at the moment, and comparing the coupling coefficient and the single-turnaverage inductance with a result obtained by the single-turn planar spiral coil model until difference values are smaller than a preset value; and finally, according to the number of turns of the transmitting and receiving coils and the parallel compensation capacitance value, obtaining transformer leakage inductance model resistance and inductance and compensation network parameters of the magnetic coupling system, and configuring circuit parameters. The method enables the system to obtain the minimum winding loss on the premise of guaranteeing the same output index.

The invention relates to a welding type fiber connector. The fiber connector comprises a ceramic pin assembly and a tail assembly, wherein the tail assembly can be passed through by an on-site optical fiber. A preset short optical fiber is arranged in the ceramic pin assembly and fusion is carried on the short optical fiber and a core wire of the on-site optical fiber, wherein the core wire passes through the tail assembly; a reinforced protective sleeved pipe is arranged at the fusion connection portion; and one end of the protective sleeved pipe is connected with the ceramic pin assembly. Advantages of the fiber connector are as follows: fusion is carried on a short optical fiber and a core wire of an on-site optical fiber, wherein the core wire passes through a tail assembly; it is notneeded to arrange a cold conjunction alignment precision mechanism in the connector, thereby simplifying the manufacturing technology; one end of a protective sleeved pipe is connected with a ceramicpin assembly, so that an overlapping amount between the end of the protective sleeved pipe and a cladding portion of the core wire of the fiber can be reduced; the protective sleeved pipe penetrates a centre bore of a spring, thereby shortening an occupied length of the protective sleeved pipe; a spring and an inner sleeve are installed in the tail assembly, thereby simplifying an on-site operation; and one end of the protective sleeved pipe is connected with the ceramic pin assembly and thus the protective sleeved pipe and the ceramic pin assembly can retreat synchronizedly, so that winding loss or damage of a short optical fiber can be avoided and thus the quality of the connector is reliable.

The invention relates to a hot wind distributor which is used for converting horizontal inlet wind to vertical outlet wind. The hot wind distributor comprises a volute casing and a wind guiding device which is installed inside an inner chamber of the volute casing; the volute casing which is provided with a wind inlet limits the hollow inner chamber; the wind guiding device comprises a circular-ring-shaped first base plate and a circular-ring-shaped second base plate which are oppositely arranged in a parallel mode; a first taper sleeve and a second taper sleeve are arranged in central holes of the first base plate and the second base plate; a wind outlet is formed between the first cone sleeve and the second cone sleeve; a plurality of arc-shaped guide plates are arranged between the first base plate and the second base plate. The hot wind distributor has the advantages of being small in tail portion wind loss and enabling the hot wind to be uniformly and straightly distributed.

The invention discloses a high-frequency transformer winding loss semi-empirical calculation method considering an end effect. The method comprises the steps of screening a decisive influence factor of an alternating-current resistance coefficient according to a geometric structure of a transformer; combining the decisive influence factors of the alternating current resistance coefficients, carrying out dimensionless processing, and determining a reasonable change interval of each dimensionless parameter; establishing a parameterized finite element simulation model of the high-frequency transformer, and calculating alternating-current resistance coefficients under the condition of different dimension parameter combinations; and selecting a fitting function, performing multivariable regression analysis, and calculating a correction coefficient to obtain a semi-empirical formula. The method is suitable for winding loss calculation of narrow foils and circular conductors under different filling rates and arrangement modes, the calculation amount and the calculation time required by optimization design are reduced, convenience and rapidness are achieved, and engineering application isfacilitated.

The invention discloses a torque ripple minimization fault-tolerance control method in loss of phase of a six-phase motor. The method, after the loss of phase of the six-phase motor, decomposes residual phase magnetomotive force into positive sequence rotational component and negative sequence rotational component so as to eliminate negative sequence synthetic component from synthesized magnetomotive force, such that the synthetic magnetomotive force of a stator is similar to circular rotating magnetomotive force. According to the invention, the method aims at weakening torque ripple in loss of phase by eliminating the negative sequence component from the synthetic magnetomotive force of the stator. If the six-phase permanent magnetic synchronous motor has a phase winding loss of phase fault, the adjustment of the phase angle of the residual phase winding current can make the magnetomotive force to approach circular rotating magnetomotive force, such as to reduce the torque ripple of the motor.

The invention discloses an ultra power efficient 3,000w bipolar three-phase asynchronous motor, which comprises a stator and a rotor. The internal diameter and core length of the stator, the slot shapes and dimensions of stator lamination slots, and the internal diameter, external diameter and core length of the rotor, and the slot shapes and dimensions of rotor lamination slots are optimized and rationally designed, so that stator winding loss is only 149.5w, rotor winding loss is only 107.4w, and core loss is only 27.5w; on the premise of the same output power of 3,000w, the conventional like product has a requirement for the input power of 3.611kw, and has energy conversion efficiency of 83.1 percent, while the ultra power efficient 3,000w bipolar three-phase asynchronous motor has the requirement for the input power of only 3.417kw, and has the energy conversion efficiency of 87.8 percent, so that energy is greatly saved, and the energy conversion efficiency is improved; and in addition, the centerline of each stator buckle slab slot is designed to penetrate through a part between two of the stator lamination slots, so that radial electromagnetic waves in air gaps are weakened, electromagnetic vibration is reduced, and electromagnetic noise is lowered.

The invention discloses a thermal aging experimental device for simulating the transformer insulation under nonuniform winding loss. The device is mainly composed of a high voltage winding (1), a low voltage winding (2), winding main insulation (3), a high voltage side direct current power supply module (4), a low voltage side direct current power supply module (5), a flow rate control acquisition module (6) and an experimental box (7). The device provided by the invention can simulate the thermal aging of the transformer insulation under nonuniform winding loss, which helps to study the thermal aging of a transformer under actual running loss to further understand the insulation state of the transformer.