12results about How to "Reduced dynamic response" patented technology

The invention provides a performance-adaptive anti-overturning vibration double-control support. The support comprises an upper convex outer cylinder and a lower convex outer cylinder, the limiting guide body is vertically arranged between the bottoms of the two outer barrels, the limiting guide body is sequentially sleeved with a first-order spring, a limiting partition plate, a second-order spring and a lower limiting base plate from top to bottom, and the upper end and the lower end of the first-order spring abut against the inner side of the bottom of the downwards-protruding outer barrel and the upper end face of the limiting partition plate respectively. The upper and lower ends of the second-order spring respectively abut against the lower end surface of the limiting clapboard and the upper end surface of the lower limiting base plate; the upper end of the limiting guide body is fixedly connected with the bottom of the downward-protruding outer cylinder, the lower end of the limiting guide body is fixedly connected with the damping tensile plate, the damping tensile plate is located between the bottom of the upward-protruding outer cylinder and the lower limiting base plate, and the space between the inner side of the bottom of the upward-protruding outer cylinder and the lower limiting base plate is filled with damping liquid; an upper limiting fixing piece and a lower limiting fixing piece are arranged on the inner side cylinder wall of the upwards-protruding outer cylinder and used for limiting or determining the upwards-moving limit position of the limiting partition plate and the downwards-moving limit position of the lower limiting base plate respectively.

The invention provides an arch-shaped energy dissipation and shock absorption supporting device for a building, which belongs to the technical field of building devices and comprises steel columns, steel beams and arch-shaped energy dissipation and shock absorption supports. The steel columns and the steel beams form a frame structure through high-strength bolts or in a welding mode. The arch-shaped energy dissipation and shock absorption support is arranged in the frame structure and is formed by welding two arch-shaped steel pipes in a crossed mode. The structure is simple and compact and installation is convenient and flexible. And secondly, the arch-shaped energy dissipation and shock absorption support has good energy dissipation performance, vibration input energy can be effectively consumed, and the dynamic response of the structure is reduced. Meanwhile, the device is made of low-yield-point steel and has high strain rate sensitivity and excellent fatigue performance. In addition, the arch-shaped energy dissipation and shock absorption support can be compatible with a conventional steel column and steel beam frame, special structural arrangement is not needed, and the actual use requirement of a building is better met. The problem that an existing energy dissipation and shock absorption device is complex in structure is solved.

The invention belongs to the technical field of aero-engine complete machine vibration, and particularly relates to an aero-engine shared bearing frame-double rotor system vibration coupling suppression method which comprises the steps that structural parameters of a shared bearing frame-double rotor system of an aero-engine are input; establishing a finite element model, and calculating to obtain a Campbell graph; selecting a dangerous rotating speed point in the working rotating speed range, calculating the transient dynamic response of the shared bearing frame-birotor system, and judging whether the transient dynamic response meets the requirement or not; and carrying out optimization design on the dangerous rotating speed points which do not meet the requirements, and repeating the steps until the transient dynamic response of the dangerous rotating speed points of the shared bearing frame-birotor system in the working rotating speed range meets the requirements. According to the invention, the vibration coupling of the common bearing frame-double rotor system of the high thrust turbofan engine under complex working conditions is effectively suppressed, so that the aero-engine has a relatively stable working state within a working speed range.

The utility model discloses a kind of viscous damping wall devices for bridge, belong to damping equipment technical field, comprising: movable member is movably inserted in damping wall, damping cavity is provided in the damping wall, damping liquid is provided in the damping cavity, the movable member sliding connection with damping cavity can be with damping liquid and shear motion occurs, the movable member includes the fixed connection of fixed part with bridge superstructure, the fixed part bottom end sliding connection has the plugboard connecting piece that can be along bridge transverse sliding, plugboard connecting piece is fixedly connected with plugboard, the plugboard sliding connection is in damping cavity.The utility model is converted into heat energy dissipation by the internal friction effect between fluid molecules, and the mechanical vibration energy of structure is continuously converted into heat energy dissipation, to effectively reduce the dynamic response of structure.

The invention relates to a permanent magnet synchronous electric drive system current harmonic suppression method considering control delay, and belongs to the technical field of permanent magnet synchronous motors. According to the current harmonic extraction method provided by the invention, only the storage space of the controller needs to be consumed, the current harmonics of each order can be extracted without the help of a low-pass filter, and the current harmonics of each order do not influence each other. The dynamic response and stability of the harmonic current closed-loop control system under the influence of control delay are analyzed, the harmonic current closed-loop control system is related to the current fundamental frequency and the proportionality coefficient, the dynamic response of the system is reduced along with rising of the fundamental frequency, and the seventh harmonic current closed-loop control system is prone to instability. PI parameters need to be designed by considering the influence of control delay.

The application discloses a large-span prestressed steel structure energy dissipation and vibration reduction self-resetting cable device, which comprises a baffle arranged on the left and right sides, a cable penetrating through the baffles, a cushion block and an anchor for anchoring the cable, a steel pull rod penetrating through the left and right baffles in sequence, a cushion plate welded at the two ends of the steel pull rod, a steel strand penetrating through the center of the steel pull rod, a second anchor for anchoring the steel strand, a spiral spring nested outside the steel pull rod and welded at the inner sides of the left and right baffles at the two ends, respectively, an upper dislocation plate welded at the inner side of the left baffle, a lower dislocation plate welded at the inner side of the right baffle, an energy dissipation device penetrating through upper and lower strip-shaped bolt holes in sequence, wherein the energy dissipation device comprises a screw rod, upper and lower nuts and upper and lower friction gaskets, and further comprises a friction energy dissipation block embedded between the upper and lower dislocation plates and a stopper for preventing the friction energy dissipation block from falling off; the device can realize energy dissipation and vibration reduction through the tensile and compressive deformation of the spiral spring and the relative sliding of the upper and lower dislocation plates, and can realize the self-resetting function through the steel strand in the steel pull rod and the spiral spring.

The invention discloses a vibration isolation system for automobile road simulation and experiment and a vibration isolation design method.The vibration isolation system comprises a vibration isolation foundation, a vibration isolation device and a vibration state detection device.The vibration isolation foundation comprises an inner foundation and an outer foundation, the inner foundation is hung downwards and supported in the outer foundation through the vibration isolation device, and the top of the outer foundation is higher than the top of the inner foundation; wherein the vibration state detection device comprises a data acquisition module and a data analysis module connected with the data acquisition module, and the data acquisition module is connected to the outer foundation, the inner foundation and the vibration isolation device. According to the invention, negative effects caused by resonance caused by the test system and the foundation can be effectively reduced, and the dynamic response of the foundation is reduced so as to meet the working requirements of a mechanical system on the table board during normal operation. And meanwhile, the dynamic response of the outer foundation can be remarkably reduced, and the vibration influence on the surrounding environment cannot be generated. The vibration response of the internal and external foundations is obtained in real time, an early warning mechanism is set, and normal work of the vibration isolation system can be guaranteed.

The invention relates to a chained SVG control system and a configuration method thereof, and belongs to the technical field of power electronics. The method is used for configuring a chained SVG control system of which a controller adopts a heterogeneous dual-core processor architecture based on an FPGA (Field Programmable Gate Array), and comprises the following steps: a control algorithm in the chained SVG control system is realized by an FPGA core, and a control logic in the chained SVG control system is realized by another core; the control algorithm comprises a virtual synchronous control function, commutation chain voltage sharing, control instruction generation and harmonic suppression; the control logic comprises chain type SVG control system start-stop control, unlocking and locking sequence control logic, chain type SVG control system state conversion and main and standby system switching. The control system comprises the controller, the controller adopts a heterogeneous dual-core processor architecture based on the FPGA, and the controller is configured by adopting the method. According to the method, on the premise that control hardware configuration is not changed, the execution time of a control algorithm is greatly shortened, and the cost is low while the control capability of the controller is improved.

This invention relates to a triangular prism-type tuned mass damper suitable for large-span cantilever structures, comprising a triangular prism box (1), a particle damping unit (4) disposed within the triangular prism box (1), and a steel mass block (3). A high-damping spring (2) is located below the triangular prism box (1). The particle damping unit (4) includes a particle damping chamber (5), three different sized particle balls, and a foamed rubber pad (9). When the structural vibration amplitude is small, the particle balls dissipate energy by compressing the foamed rubber pad and rolling; when the structural vibration amplitude is large, the particle balls dissipate energy by colliding and compressing the foamed rubber. Compared with the prior art, this invention achieves a phased energy dissipation mechanism while solving the problems of narrow vibration reduction bandwidth, large motion stroke, and noise generated by particle collisions in traditional mass tuned dampers.

The invention discloses a photovoltaic array adaptive global maximum power point tracking method and system. The method comprises the following steps: solving global maximum power point reference voltage and global maximum power point reference power output by a photovoltaic array based on current environment data by adopting a two-stage nested multi-strategy particle swarm algorithm; judging whether a preset accurate control switching condition is met or not according to the output power of the photovoltaic array and the global maximum power point reference power; if a precise control switching condition is met, switching to a self-adaptive super-spiral sliding mode control mode, otherwise, maintaining a PI control mode; driving a power switch tube in the DC-DC converter to act by using a PI control mode or a self-adaptive super-spiral sliding mode control mode; according to the method, reference parameters are solved through the two-stage nested multi-strategy optimization particle swarm optimization algorithm, a dual-mode switching mechanism of PI control and self-adaptive super-spiral sliding mode control is matched, accurate and rapid tracking of the global maximum power point in a complex environment is achieved, and steady-state power fluctuation is effectively restrained.

The utility model provides a kind of bicycle hub and bicycle, it is related to bicycle technical field, including axle core and the shell and tower base of being sleeved on axle core, wherein shell and tower base are formed with the installation cavity for assembling ratchet structure between, ratchet structure includes first ratchet piece, second ratchet piece and elastic piece, first ratchet piece and second ratchet piece are all sleeved on axle core, first limiting portion for being limited with first ratchet piece along the circumference is shaped in shell, second limiting portion for being limited with second ratchet piece along the circumference is shaped in tower base, elastic piece is located in the other side of second ratchet piece relative to first ratchet piece, to make first ratchet piece limit along the axial direction, second ratchet piece can reciprocate along the axial direction, so that the second helical tooth on the end face of second ratchet piece and the first helical tooth on the end face of first ratchet piece can be one-way engagement. To improve the problem that existing bicycle hub structure is easy to wear and tear and the number of parts is more.

The invention provides an offshore wind turbine cable protection device using buoyancy blocks. The offshore wind turbine cable protection device comprises a cable suspension section protection assembly and a cable towing section protection assembly. The cable suspension section protection assembly comprises an internal anti-bending device, an external anti-bending device and a spiral strake sleeve, the internal anti-bending device is connected with the external anti-bending device through barbs, and the spiral strake sleeve is connected with the external anti-bending device through a sleeve joint; the cable towing section protection assembly comprises an anti-abrasion sleeve and a buoyancy block, the anti-abrasion sleeve is connected with the spiral strake sleeve, and the anti-abrasion sleeve is sleeved with the buoyancy block. According to the invention, the comprehensive protection of the cable is realized, the overall dynamic response and vortex-induced vibration response of the fan cable under the action of wave current can be effectively reduced, the wear of the cable is remarkably reduced, and the service life of the fan cable is prolonged.