31results about How to "Solve the stall problem" patented technology

The invention discloses a field installation method for a vertical-shaft wind-driven generator. The method comprises the following steps of: (1) constructing a bottom base of a central tower column; (2) constructing a reinforced concrete central tower column on the bottom base; (3) installing a crane on the top of the central tower column; and (4) constituting a generating unit by using each installation platform, a generator, a wind wheel and generating equipment, and hoisting all generating units from top to bottom in sequence by using the crane. Each generating unit is hoisted by using the crane according to the following steps of: (a) hoisting a blade onto the central tower column; (b) hoisting a shaft coupling onto the central tower column and connecting with the wind wheel; (c) hoisting a main gear onto the central tower column and connecting with the shaft coupling; and (d) hoisting the generator and the generating equipment onto the installation platform, and meshing the generator with the main gear through a gear transmission system. Due to the adoption of the method, the vertical-shaft wind-driven generator is convenient to install and debug, the installation period is short, and the installation cost is low.

The invention relates to a buffering device and buffering control method for a rocket flexible steel cable erecting system. The buffering device comprises a buffering mechanism and a butt joint mechanism, wherein the buffering mechanism comprises supporting arms, guide pulleys, reversing pulleys, a limiting rod, a traction rope and a pendant; the supporting arms are fixed on a fixed frame, and thesupporting arms are fixedly connected with two limiting plates; the two limiting plates are provided with limiting clamping grooves; guide pulleys are mounted on the fixed frame and the reversing pulleys are mounted on the supporting arms; the guide pulleys and the reversing pulleys are correspondingly arranged on the left sides and the right sides of the limiting plates; the limiting rod is arranged in the limiting clamping grooves of the limiting plates and is connected with one end of the traction rope, and the other end of the traction rope bypasses the reversing pulleys and the guide pulleys to be connected with the pendant; and the butt joint mechanism comprises butt joint arms fixed on a erecting frame, two butt joint plates are fixed at the upper ends of the butt joint arms, and butt joint clamping grooves are formed in the upper sides of the two butt joint plates. The buffering device has the advantages of being simple in structure, stable in action and good in buffering effect. The buffering control method has the advantages of being simple in flow and easy in implementation.

The invention provides an areca nut belt type conveying and seed cutting machine which comprises a machine base, a seed cutting mechanism and a feeding mechanism. The seed cutting mechanism is provided with a cutter, the feeding mechanism comprises a driving chain wheel, a driven chain wheel and a chain, and the chain winds on the driving chain wheel and the driven chain wheel. The areca nut belt type conveying and seed cutting machine is characterized in that multiple mold base plates are arranged on the chain, a seed feeding mold is arranged on each mold base plate, the seed feeding molds mounted on the mold base plates are connected in a front and back mode, multiple shifting blocks with grooves are arranged at one ends of the seed feeding mold, the shifting blocks correspond to the cutter, and a line groove corresponding to the cutter is formed on each seed feeding mold. The areca nut belt type conveying and seed cutting machine with the structure can carry out half cutting work on areca nuts efficiently and conveniently, the slicing efficiency of areca nut seeds is improved greatly, and the structure is simpler.

The invention relates to the field of robot trajectory planning, and provides a smooth transition method of multi-space trajectory planning of a teaching robot, aiming at solving the unsmooth problemin the trajectory switching process. The smooth transition method comprises the steps that a teaching program of the teaching robot is analyzed, the switching direction of the trajectory planning is judged, if the trajectory planning is that the switching direction is from cartesian space to joint space, a tail end of cartesian space trajectory planning is acquired, according to the requirements on a path and a velocity, a first posture and a first velocity at the tail end are acquired, first angular velocities of various joints are obtained by employing a jacobi matrix, and by taking an angleindicated by the first posture as a starting angle and the first angular velocities as starting velocities, joint space trajectory planning is carried out; or else, a starting point of the cartesianspace trajectory planning is acquired, a second posture at the starting point and second angular velocities of the various joints are obtained, and by taking an angle indicated by the second posture as a terminal angle and the second angular velocities as terminal velocities, the joint space trajectory planning is carried out. Smooth transition of the trajectory planning in space switching is realized.

The invention discloses a system and a method for protecting a pitch system in a wind power generating set grid phase failure. The state is controlled by the auxiliary contact of the intermediate relay powered by the switching power supply; the intermediate relay is connected to the driver, and the driver can determine the input or output signal according to whether the DC bus voltage exceeds the limit. The invention can eliminate hidden dangers such as overspeed and load overrun caused by the pitch control system when the grid voltage lacks phase, and improves the safety performance and automation degree of the unit.

The invention relates to the technical field of injection molding and discloses an injection molding screw structure for stall braking by using an electrorheological fluid principle. The injection molding screw structure comprises a mounting base; a movable groove I and a movable groove II are separately formed in the mounting base; a brake mechanism I is arranged in the movable groove I; and a brake mechanism II is arranged in the movable groove II. According to the injection molding screw structure for stall braking by utilizing the electrorheological fluid principle, through cooperative useof the brake mechanism I, the brake mechanism II, a coil and a conductor, when the rotating speed of a rotating shaft exceeds a rated rotating speed, automatic braking can be realized, and the rotating speed of the rotating shaft is reduced to a rated value, so that the rotating speed of a screw connected with the rotating shaft is reduced, and the problem that the rotating speed of the screw isdifficult to control or stall due to plastic materials, different injection molds and setting of wrong machining parameters is solved, the quality and the percent of pass of formed products are greatly improved, the service life of parts is prolonged, and the income of enterprises is increased.

The invention discloses a design method of a novel CMG control law with feedforward compensation, which belongs to the field of spacecraft control. A spacecraft GNC module not only calculates the frame angular velocity instruction of each CMG in each control period, but also calculates the gyroscopic moment applied to each CMG frame axis due to the influence of the star angular velocity, and the two parts are simultaneously provided for a CMG single machine for determining the control law. Compared with the prior art, the method provided by the invention has the advantages that feedforward compensation is carried out on the CMG single machine by utilizing the information of the gyroscopic moment, so that the constraint on the star angular velocity is relaxed, and the problem of CMG stall occurring when the star angular velocity is relatively high is solved.

The invention relates to a hoisting and erecting system and an erecting control method for a rocket launch platform at sea. The hoisting and erecting system includes an erecting unit and a buffer unit, and the erecting unit includes a hoist, an erecting steel wire rope, an erecting pulley and a connection Ring; the buffer unit includes a support arm, a buffer pulley, a reversing pulley, a limit rod, a buffer wire rope, a pendant and a docking arm. The support arm is fixed with two limit plates, and the left side of the two limit plates is provided with a limit card slot, the limit rod is in the limit card slot of the two limit plates, the limit rod is connected to one end of the buffer wire rope, the other end of the buffer wire rope is connected to the pendant by bypassing the reversing pulley and the buffer pulley, and the docking arm is fixed on On the erecting frame, two docking plates are fixed on the upper end of the docking arm, and the upper side of the two docking plates is provided with a docking card slot, which has the advantages of simple structure, stable movement, safety and reliability, good cushioning effect and strong adaptability. The erecting control method has the advantages of simple process, easy realization and high safety.

The invention relates to a buffer device and a buffer control method for a rocket flexible steel cable erecting system. The buffer device includes a buffer mechanism and a docking mechanism. The buffer mechanism includes a support arm, a guide pulley, a reversing pulley, a limit lever, a traction rope and a pendant The support arm is fixed on the fixed frame, the support arm is fixed with two limit plates, and the two limit plates are provided with limit card slots, the guide pulley is installed on the fixed frame, the reversing pulley is installed on the support arm, and the guide pulley Corresponding to the reversing pulley, it is located on the left and right sides of the limit plate. The limit rod is located in the limit slot of the limit plate and connected to one end of the traction rope. The other end of the traction rope bypasses the reversing pulley, the guide pulley and the pendant. Connection; the docking mechanism includes a docking arm fixed on the erecting frame, two docking plates are fixed on the upper end of the docking arm, and a docking card slot is provided on the upper side of the two docking plates. The utility model has the advantages of simple structure, smooth action and good cushioning effect. The buffer control method has the advantages of simple process and easy implementation.

A device and method for preventing velocity loss during strong wind for vertical-shaft wind power generators. At least one power generating unit is disposed on a tower column (1). A crane (4) is disposed on the top of the tower column. The crane is disposed with a hook (42). A blade assembly comprises at least two blades (3). The blade is bow-shaped and consists of a chord-shaped part (32) and a corresponding arc-shaped part (31). At least one supporting arm (11) is disposed between the chord-shaped part and the arc-shaped part. Multiple lift lugs (12) onto which the hook hangs are disposed on the supporting arm. At least two rollers (13) are disposed on the chord-shaped part. Tracks (8) are disposed in each power generating unit, the number of the tracks being equal to the number of blades. The tracks are synchronous to the blades. The arc-shaped part and the rollers form a sliding mechanism that is complementary to the movement of the tracks. The upper end and the lower end of the blade are disposed with male connecting mechanisms. Female connecting mechanisms are disposed on the track at positions corresponding to the upper end and the lower end of the blade. The male connecting mechanisms and the female connecting mechanisms complement each other. During strong winds, the crane lowers the blades onto the ground in the order from the bottom to the top. The device is easy to operate and solves the problems of velocity loss of power generators and blade breakage during strong wind and typhoon, thereby ensuring the safety of the power generators.

Disclosed is a method for installation of a vertical-axis wind generator. The method comprises the following steps: (A) constructing the foundations of a central pylon (1); (B) constructing a reinforced concrete central pylon on the foundations; (C) installing a hoist (5) at the top of the central pylon; (D) each mounting platform (3), generator (4), wind wheel (2) and power generating device constituting a power generating unit, and according to the following steps, the hoist lifting successively from top to bottom all the power generating units: (a) lifting blades (21) onto the central pylon; (b) lifting a shaft coupling (6) onto the central pylon and connecting same with the wind wheel; (c) lifting a master gear (10) onto the central pylon and connecting same with the shaft coupling; and (d) lifting the generator and the power generating device onto the mounting platform, and meshing the generator with the master gear via a gear transmission system. The present method involves convenient installation and debugging, short construction time, and low costs.

The invention provides an anti-stall double-layer pump inlet structure. A horn seat and a separation seat are arranged at the pump inlet, both of which are bell mouth structures. The separation seat is covered on the surface of the horn seat through the support, and the other is There is an annular gap between them, so that the water inlet channel of the pump is divided into two parts, of which the main inlet is located in the center, and the auxiliary inlet is formed by the gap between the horn seat and the separation seat. The water inlet channel of the pump is divided into two parts: the main inlet and the auxiliary inlet through the separation seat. When the pump is running in a small flow condition, the backflow at the pump inlet is discharged outward by the above-mentioned sub-inlet, so as to avoid the main inlet caused by the backflow. Blockage, solve the stall problem under small flow conditions, improve the anti-stall performance of the pump, and expand the scope of application of the pump.

The invention discloses a method for avoiding stall caused by strong wind in a vertical axis wind turbine. The tower is provided with more than one power generation unit, a crane is arranged at the top of the tower, and the crane is provided with a hook; the blade group comprises more than two blades, the blade is arc-shaped and consists of a chord and a corresponding arc, more than one support arm is arranged between the arc and the chord, and the support arm is provided with a plurality of lugs hung by the hook; both the upper end and the lower end of the blades are provided with male connecting mechanisms, female connecting mechanisms are arranged on tracks corresponding to the upper ends and the lower ends of the blades, and the male connecting mechanisms are matched with the female connecting mechanisms; and in strong wind, the blades are hoisted to the ground sequentially from bottom to top through the crane. The method is simple in operation, can solve the problems of stall of the generator set and breakage of the blades in ultra strong wind or typhoon, and ensures the safety of the generator set.

The invention discloses a motor control method, comprising the following steps: detecting the rotational speed of the motor; calculating the rotational speed change rate of the motor according to the detected rotational speed of the motor and a given rotational speed of the motor; when the rotational speed change rate of the motor is greater than a preset value , adjust the proportional-integral parameter of the speed loop in the motor control system, and adjust the lower limit of the q-axis current upper limit of the motor. The control method of the motor avoids motor overcurrent or stall failure caused by abnormal current, and ensures safe and reliable operation of the motor under low-frequency heavy load and during the entire operation process. The invention also discloses a motor control system.

A stall-eliminating blower for blowing or exhausting is composed of casing, motor, vane wheel and airflow collector, and is characterized by its additional reverse-flow unit, which can make the eddy flow caused by stall flow reversely back to main flow channel, so eliminating stall.