1046 results about "Static performance" patented technology

The invention discloses a polymer/graphene anti-static coating, a preparation method and application thereof. The coating comprises the following constituents by weight percent: 0.01 portions to 0.5 portions of graphene; 0 portion to 10 portions of conductive additive; 90 portions to 100 portions of polymer; and solvent; the preparation method thereof comprises the following steps: completely and uniformly mixing graphene and conductive additive in advance by various manners; preparing a graphene-conductive additive compound system; using the compound system as a base, adding in conductive additive and polymer along with the solvent, completely and uniformly mixing to obtain the coating. Additionally, an anti-static film can be prepared by using different film forming technologies. The polymer/graphene anti-static coating, the preparation method and application thereof effectively solve the problems that graphene in polymer is easy to agglomerate and difficult to be uniformly dispersed in the preparation process of anti-static coating and film; the anti-static performance and mechanical performance of the coating and the film are greatly increased; meanwhile, the preparation technology is easy to be operated; the production is continuous, and the coating and film are suitable for industrial production.

A comprehensive test experiment device for dynamic and static properties of a rolling bearing-main shaft system comprises a main shaft in which the front end is installed on a front end bearing support saddle; the end surface of the front end bearing support saddle is provided with three laser displacement sensor test probes; the front end bearing support saddle is internally provided with an experiment bearing; load is carried out through a radial load hydraulic tank and an axial load hydraulic tank; the back end of the main shaft is assembled on a back end bearing support saddle, and the back end bearing support saddle is configured to be paired angle contact bearings, and both an integrated monitoring ring and a pre-tightening push block are installed between the angle contact bearings to realize self-adapting pre-tightening of the bearing; the main shaft is provided with an eccentric quality shock excitation disk for applying bearing shock excitation; and the main shaft is driven by a variable-frequency electric motor. The comprehensive test experiment device for dynamic and static properties of a rolling bearing-main shaft system is used for detecting the influence on the dynamic and static properties of multiple types of bearings and the main shaft system, thereby overcoming the defect that the existing rolling bearing-main shaft experiment platform has the characteristics of single-type tested bearing, too low integration degree and rough single processing, being capable of carrying multiple experimental researches, and improving the flexibility of the rolling bearing-main shaft experiment platform.

The invention discloses a control method of a four-phase permanent magnet fault-tolerant motor. In the method, a control mode can be automatically decided according to the diagnosed situation of a system failure; when the system is at a normal state, an SVPWM control is adopted; when the system has a phase-lacking failure, a fault-tolerant torque control is adopted; different fault-tolerant control proposals are adopted according to different types of phase-lacking failures. The control method realizes that the four-phase permanent magnet fault-tolerant motor can operate with high performance under the normal condition and the phase-lacking condition, overcomes the deficiency that the stable performance of the system when in normal working is reduced in the traditional fault-tolerant control system which adopts current for regulating PWM for realizing current tracing for the convenience of fault-tolerant control, establishes a mathematical model of the four-phase permanent magnet fault-tolerant motor under a rotating coordinate system, successfully applies an SVPWM strategy to the four-phase permanent magnet fault-tolerant motor and enhances the dynamic and static performances and reliability of the control system of the four-phase permanent magnet fault-tolerant motor.

The invention provides a quantitive type experimental device for dynamic and static performances of a static-pressure rotary table, and belongs to the field of machinery design and manufacture. According to the experimental device, a loading device (5) and a loading arm (6) are used for changing magnitude of loads or changing oil supply pressure to control the distance between a static-pressure oil cushion (10) and a rotary table disc chuck (7), a pressure sensor (12) is used for measuring pressure in an oil cavity, an eddy current displacement sensor (11) is used for measuring the thickness of an oil film, a thermocouple temperature sensor (3) is used for measuring oil temperature, a force sensor (4) is used for obtaining magnitude of loading force, a pressure gauge a (15) on a multi-head pump at an oil inlet in the oil cavity is used for measuring pressure of the oil inlet of the oil cavity, and a pressure gauge b (16) arranged between an oil pump and the multi-head pump is used for measuring the oil supply pressure of the static-pressure rotary table. By means of the experimental device, a test of the dynamic and static performances of the static-pressure rotary table is carried out under the condition that temperature is between minus 10 DEG C and 60 DEG C and pressure is not more than 100 MPa, and the experimental device provides guarantee for solving problems in engineering, optimizing structural parameters of the rotary table, and improving machining precision of the rotary table.

The three degree of freedom radial-axial direction mixing magnetic bearing, and two degree of freedom bearingless permanent magnet synchronous motor are used to compose 5 degree of freedom bearingless permanent magnet synchronous motor digital-control servosystem. Three independent PID linear controllers are used to make independent control. Through adjusting control parameter of PID controllers, implements steady operation of the mixing magnetic bearing. The hall sensor is used to detect the size of magnetic field of rotator, and directional control strategy based on rotator field is adopted to make dynamic decoupling control. Through adjusting parameter of two PI controller in location control ring, ensures redial direction suspension system of bearingless motor has good dynamical and static property. Through adjusting parameters of three PI controller in rotating speed control ring, ensures the rotating speed has good response property.

The invention discloses a carbon-reinforced halogen-free fire-resistant nylon 66, which comprises by weight: nylon 66 resin 30-50 portions, long carbon fiber 10-50 portions, covering red phosphorus substrate 5-20 portions, fire resisting assistant 0-20 portions, flexibilizer 0-10 portions, antioxidant 0.1-1 portions, and processing assistant 0.1-15 portions. The carbon-reinforced halogen-free fire-resistant nylon 66 made by the invention is of high strength, high modulus, small creepage, and permanent anti-static performance, also good fire resistance, high mechanical strength, is resistant to high temperature, light, easy to process, with good fire resistance, and is also environmental friendly. The preparing method of the invention is simple to operate and applicable for industrialized production.

The invention discloses an identification method of a second order resistance and capacitance (RC) equivalent model of a power lithium battery based on a second order RC model. The identification method of the second rate RC equivalent model of the power lithium battery includes the steps of confirmation of an identification equation of the second order RC equivalent model, acquisition of identification data, calculation of battery ohm internal resistance and identification of the least square method. By means of the identification of the second order RC equivalent model of the power lithium battery, the dynamic and static performances of the battery can be reflected well; on one hand, the RC equivalent model has more precise characterization electrical parameters, the dynamic behavior of charging and discharging of the battery can be simulated scientifically and precisely in consideration of temperature, current and internal resistance difference in the process of charging and discharging; on the other hand, the order of the model is two, no complicated mathematical calculation is needed, and thus a computer can process the model conveniently. Therefore, a mathematical model is established by using the second order RC equivalent model, the state of charge (SOC) of the battery can be evaluated scientifically and precisely, and the identification method of the second rate RC equivalent model of the power lithium battery can be widely used in the research and application of the power lithium battery.

The invention provides a three-degree-of-freedom-motion permanent magnetic spherical step motor. The motor is characterized in that a permanent magnet groove is arranged on a spherical hollow rotor housing, coil holes are distributed on a spherical stator housing on the periphery of a spherical rotor, a stator winding coil is arranged in the coil holes; an output shaft is fixedly connected with the spherical hollow rotor housing; a semispherical housing is fixedly arranged on the output shaft on the periphery of the spherical stator housing, center of the housing is coincident with that of the spherical hollow rotor housing, and a code pattern is arranged on the surface of the housing. The three-degree-of-freedom-motion is realized by the spherical structure, and position of the rotor can be detected by a machine vision method to solve the difficult detection problem of the motor rotor position. The motor is subject to feedback control according to the obtained rotor position, thus simplifying structure of the three-degree-of-freedom mechanical device, and enhancing dynamic and static performances and control precision of a system.

The invention relates to a preparation method for an acrylic resin/graphene oxide nanometer composite leather finishing agent. In the preparation method, a nanometer graphene oxide suspension liquid is formed through peeling and dispersing; and then the acrylic resin/graphene oxide nanometer composite acrylic resin finishing agent is prepared through in-situ polymerization. The preparation methodcomprises the following specific steps: carrying out oxidization and ultrasonic stripping on natural graphite powder to prepare graphene oxide; adding graphene oxide to a mixed monomer of methyl acrylate, ethyl acrylate, butyl acrylate, acrylic acid and hydroxyethyl acrylate under the action of ultrasonic waves; and carrying out in-situ free radical copolymerization reaction under the action of an initiator ammonium persulfate to obtain the acrylic resin/graphene oxide nanometer composite leather finishing agent. The preparation method has the characteristics that the acrylic resin/graphene oxide nanometer composite leather finishing agent with excellent film-forming hand feel, strength and anti-static performances and no heat bonding and cold brittleness defects is prepared by using the specific laminated structure and performance of graphene oxide.

The invention relates to a low and medium power high frequency DC-DC converter suitable for high-voltage input, which is based on the fundamental principle that: series capacitors are connected to a high-voltage direct current input, each capacitor serves as an input of the high-frequency forward DC-DC converter, and the outputs of the high-frequency forward DC-DC converter share a filter inductor, a freewheeling diode and an output filter capacitor; voltage feedback is acquired by sampling the output voltage of the high-frequency forward DC-DC converter, and a given reference voltage is compared with the voltage feedback so as to obtain a voltage loop output, namely a main output, by voltage regulation and calculation; and then, high-frequency forward DC-DC converter driving signals which are equational and alternate in phase are acquired to realized the control over a main circuit. The DC-DC converter has the advantages that: a low-voltage switching element is used under high voltage direct current input; the topology is simple; the cost is low; and the output has excellent dynamic and static performance.

A flexible integrated test system of dynamic and static properties of a combination automotive body-in-white comprises a portal frame, a support restraint device, an adjustable concentrated force loading device, a torsion pendulum frame loading device and a measuring appliance assembly. The support restraint device for supporting the automotive body-in-white to be tested is fixed on the portal frame, the measuring appliance assembly is fixed on the portal frame by a support or directly fixed on the portal frame, the adjustable concentrated force loading device and the torsion pendulum frame loading device which loads stress on the automotive body-in-white to be tested are fixed on the portal frame or arranged on the peripheral side of the portal frame. The flexible integrated test system of dynamic and static properties of the combination automotive body-in-white has the advantages of simple and compact structure, reasonable layout, convenient operation, comprehensive function, wide application and good expansibility.

A double-ring dead-beat prediction control method for a permanent magnet synchronous motor based on disturbance estimation compensation comprises the following steps: establishing a discrete current prediction model of the permanent magnet synchronous motor, and designing a dead-beat current prediction controller; designing a sliding mode disturbance observer to estimate stator current and parameter disturbance; designing a dead-beat speed prediction controller; and designing a sliding mode disturbance observer to observe and compensate the load torque. According to the invention, under the condition that motor model parameters are not matched, the method achieve the accurate current control; under the condition that the dead-beat speed prediction controller is sensitive to load change, the method achieves the improvement of the dynamic and static performance and the anti-disturbance performance of the speed outer ring through load torque observation and compensation.

The invention discloses a polyurethane-water glass composite grouting material as well as a preparation method and an application thereof. The polyurethane-water glass composite grouting material comprises a component A and a component B in a weight ratio of 1:1-1:2, wherein the component A comprises the following components in percentage by weight: 72%-83% of polyurethane prepolymer, 5%-15% of plasticizer, 5%-10% of flame retardant and 2%-3% of surfactant, and the component B comprises the following components in percentage by weight: 99.2%-99.5% of water glass and 0.5%-0.8% of antistatic agent. The obtained composite grouting material has low slurry toxicity and relatively good compressive strength, is dense in jet-grouted solid and does not foam when being wet; and the flame retardancy and the anti-static performance of the composite grouting material meets the requirements of national coal industrial standards MT113-1995; and the polyurethane-water glass composite grouting material can be used for reinforcing coal seams of coal mines.

The invention belongs to a fatigue life determining technology for an operating system of an aircraft and relates to a fatigue test method for a full-aircraft main operating system of the aircraft. According to the fatigue test method, the fatigue coordination loading of an operating load and an operating displacement can be carried out, a fatigue test including the operating load and an operating displacement spectrum on the full-aircraft main operating system of the aircraft can be implemented, and meanwhile, the problem of simultaneous test of aircraft body fatigue on the same fatigue testing machine is taken into account, so that the fatigue properties of components and supporting parts of the full-aircraft main operating system and static performance indicators of the full-aircraft main operating system are all actually assessed; the actual loaded conditions of the main operating system of the aircraft under normal operating and emergency operating conditions are more truly reflected, the fatigue properties of the structure and mechanism of the main operating system of the aircraft are embodied; and the test cost is reduced, and the reliability of a test result is improved.

The invention relates to a method for sorting the consistency of lithium titanate single batteries. According to the method, both static performance parameters such as capacity, voltage and internal resistance and dynamic parameters such as polarization impedance, large-current charging-discharging capacity and self-discharging capacity are considered. The method comprises the following steps that1, primary sorting is carried out according to parameters such as discharge capacity, open-circuit voltage and alternating-current internal resistance; 2, secondary sorting is carried out after the single batteries undergo high-temperature standing for a period of time; and 3, third-time sorting is carried out on the single batteries subjected to secondary sorting by detecting high-rate pulse discharge conditions, and finally the lithium titanate single batteries with high consistency are obtained. According to the method, the problem that the consistency of single batteries in an existing lithium titanate battery system is difficult to sort is solved; the performance of the battery packs which are formed by the lithium titanate single batteries sorted through the method can be better than that of battery packs which are grouped through a common grouping method; and meanwhile, compared with an existing conventional sorting method, the sorting method is simple to operate, free of redundant equipment investment, short in testing time, and facilitates industrial popularization and application.

A computing system for determining performance factors for using in performance modeling of a deployed subject system, is presented. The computing system includes a plurality of software components comprising the subject system. Each of the components is susceptible to event tracing while executing on the computing system. The computing system includes a tracing component. The tracing component is configured to trace events of the components of the subject system as they execute. The computing system includes a transaction identification table. The transaction identification table comprises starting and ending actions for transactions performed by the subject system. The computing system also includes a transaction identification component that identifies actions from traced events, identifies related actions corresponding to a transaction according to the starting and ending actions in the transaction identification table, and stores the related actions in the transaction workflow data store.

The invention provides a modularized static stiffness testing device for angular contact ball bearings. The testing device comprises a square box for fixing the testing device, bearings supported by a simulating shaft, an outer ring sleeve sleeved outside the bearings, axial and radial loading devices and axial displacement and radial displacement measuring devices; the axial displacement measuring device can detect whether the bearings are deflected by adopting two sets of displacement sensors; the radial displacement measuring device can detect whether the radial loads borne by the two bearings are the same by adopting two sets of displacement sensors; and the simulating shaft is positioned through a positioning ring and a loading sleeve during axial stiffness test. By adopting the modularized structural design, the device can realize the static stiffness test of the angular contact ball bearings of different size series, and can test axial stiffness and radial stiffness at the same time. The device has the advantages of simple structure, multiple functions and wide application range, can acquire real stiffness values of the angular contact ball bearings, and has significance for searching the static performance of the angular contact ball bearings and determining reasonable pre-tensioning force of the bearings.

The invention discloses an outdoor sportswear fabric. The outdoor sportswear fabric comprises a surface layer coating, a middle layer fabric and an inner layer fabric, wherein the inner layer fabric is formed by blending and weaving superfine polyester fibers, bamboo fibers and Coolplus fibers; the middle layer fabric is formed by blending and weaving superfine polyester fibers, Coolplus fibers and copper ammonia fibers; the surface layer coating is a polyester waterproof coating. By adopting a blending and weaving mode, the blended and woven fibers have good anti-bacterial and anti-static performances and wearability. According to the invention, a special waterproof treatment and antibacterial and uvioresistant treatment technology is adopted, so that not only are the good antibacterial, uvioresistant and waterproof effects ensured, but also the wearability of the outdoor sportswear fabric can be ensured maximally.

The invention discloses an optimal two-vector combination-based model predictive control method and system. The method is applied to a permanent-magnet synchronous motor control system driven by a three-phase two-level inverter. A model predictive current control strategy is adopted, all two-vector combinations and resultant vector sets obtained under action time are considered at the same time, and a cost function is inspected and an optimal resultant vector is selected from all to-be-selected sets. In order to simplify the optimization process, an equivalent voltage equation is given, a sector transformation method is provided and to-be-selected two-vector combination sets are transformed into multiple fixed line segments; and a fast algorithm is given and partial complicated calculation is transformed to offline execution, so that the real-time calculated amount of the novel method is effectively reduced. The model predictive control method disclosed by the invention is simple in structure, small in real-time calculated amount and easy to implement; and the response speed of a motor is high, current ripples and distortion are small, the switching frequency is low and the dynamic and static performance of the system is excellent.

The invention provides a method for computing equivalent elastic parameters of a fiber reinforced composite material, and belongs to the technical field of calculation of statics performance parameters of composite materials. A composite material micro-structure model is established by using an XCT (X-ray computed tomography) technology and more approaches a true situation; important parameters affecting elasticity modulus, such as fiber bundle shape, fiber volume ratio, porosity and pore distribution, can be automatically obtained without a hypothesis. The method is more reasonable, higher in computation accuracy, and more universal in flow; various paradoxical hypotheses and complicated mathematical derivations are eliminated, and an engineer accepts and masters the method more easily.

The invention relates to a support vector machine inverse system composite controller based on a bearingless synchronous reluctance motor. Two expandable current hysteresis loop PWM (Pulse-Width Modulation) inverters and a bearingless synchronous reluctance motor to be controlled are used as a whole to form a composite object to be controlled; a support vector machine inverse system controller is constructed according to a mathematical model of the object to be controlled and is connected in series before the composite object to be controlled of the bearingless synchronous reluctance motor so as to realize the decoupling control between the electromagnetic torque and the radial levitation force of the motor as well as the radial levitation force in two vertical directions; on the basis, a rotating speed closed loop linear controller and two rotor position closed loop linear controllers are respectively designed for the rotating speed of the motor and the rotor positions to form a linear closed loop controller; an finally the linear closed loop controller, the support vector machine inverse system controller and two expandable current hysteresis loop PWM inverters commonly form the support vector machine inverse system composite controller for dynamically decoupling control on the bearingless synchronous reluctance motor. The control speed, the control precision and the dynamic and static performances of the system can pass parameters for adjusting the linear closed loop controller.

The invention discloses a preparation method of high-density fine-denier double-surface double-layer PFY (Polyester Filament Yarn) fabric. The preparation method comprises the following steps of (1) raw material selecting; (2) space-variant compositing and sizing; (3) weaving; (4) dyeing and after-finishing. The high-density fine-denier double-surface double-layer PFY fabric which is generated by the preparation method has the characteristics that the fabric density is up to 120/cm, the fineness is only 50 denier, the finest fiber is only 0.02 DPF, the fabric is woven by adopting a double-layer exterior and interior interconnection organization, the thinnest thickness can be lower than 100 g/m<2>, the fabric is fine and smooth in weaving, abundant pattern textures, color matching and check and pattern combination can be formed, the feeling is soft and comfortable, the recoverability is strong, the air permeability, the water vapor permeability and the anti-static performance of the fabric are good, and the fabric is ideal fabric for manufacturing sports wear, jackets and suits. The comprehensive running rate of a weaving machine is up to 95%, the cloth surface is smooth, and the product yield is ensured.