69results about How to "Suppress torsional vibration" patented technology

An apparatus and method for damping vibration, especially torsional vibration due to stick-slip, in a drill string, Sensors measure the instantaneous angular velocity of the drill string at one or more locations along the length of the drill string. One or more vibration damping modules are also spaced along the length of the drill string. When torsional vibration above a threshold is detected, the damping module imposes a reverse torque on the drill that dampens the torsional vibration. The reverse torque can be created by imparting a frictional resistance to the rotation of the drill string. The frictional resistance can be created externally, by extending friction pads from the damping module so that they contact the bore hole wall and drag along the bore hole as the drill string rotates, or internally by anchoring a housing mounted on the drill string to the wall of the bore hole and then imposing frictional resistance on a fluid, such as a magnetorheological fluid, flowing within the drill string.

In a parallel hybrid vehicle, a controlling section controls an engine and a motor/generator, a torque from the engine and the motor/generator being transmitted to driven wheels via a transmission and a drive shaft. The controlling section comprises: an engine torque calculating section that calculates an engine torque and a torsional vibration suppression torque calculating section that calculates a torsional vibration suppression torque to suppress a torsional vibration developed on the drive shaft according to the engine torque calculated by the engine torque calculating section, the torsional vibration suppression torque calculated by the torsional vibration suppression torque calculating section being outputted from the motor/generator.

A control device capable of executing damping control of outputting a damping torque command that suppresses vibration of a rotational speed of a rotating electrical machine caused at least by elastic vibration of a power transmission mechanism. This is accomplished by using feedback control based on the rotational speed of the rotating electrical machine. The control device executes the damping control by a direct-coupling damping controller when the engagement state of the engagement device is a direct-coupling engagement state in which there is no rotational speed difference between engagement members, and executes the damping control by a non-direct-coupling damping controller different from the direct-coupling damping controller in a case where the engagement state of the engagement device is a non-direct-coupling engagement state other than the direct-coupling engagement state.

The invention relates to an input reshaper parameter self-tuning control method based on a particle swarm optimization algorithm, and belongs to the technical field of drive control methods in the staring process of coaxial transmission machines. According to the buffeting problem in the staring process of coaxial transmission machines, a transmission mechanism is controlled in a feedforward mode through the control method, and effectiveness and feasibility of the control method are proved through experimental results; in the off-line state, a dipulse input reshaper is optimized by using the particle swarm optimization algorithm to obtain the optimal parameter, and then an actuator is controlled in a feedforward mode by using the obtained optimal input reshaper. According to the torsional vibration problem in the staring process of the coaxial transmission printing machines, an input reshaper parameter self-tuning control algorithm based on particle swarm optimization is provided. According to the control method, while torsional vibration of a system is restrained substantially, dynamic performance of the system is sacrificed little, and a rapid vibration-free response of the system is achieved.

The invention provides a method and a system for inhibiting torsional vibration of a power system of an electric vehicle. The method comprises the following steps of calculating a theoretical motor rotating speed according to an actual wheel rotating speed and a preset power system speed ratio; calculating a motor rotating speed variable quantity according to an actual motor rotating speed and the theoretical motor rotating speed; calculating a motor output torque according to the motor rotating speed variable quantity and preset parameters; controlling a motor to operate according to the output torque. The method and the system provided by the invention have the advantages that the actual motor rotating speed is matched with the theoretical motor rotating speed when the motor is controlled to operate by utilization of the output torque, so that the rotating speed fluctuation of the motor is stabilized, and the torsional vibration of the power system is inhibited, therefore the jittering problem of the electric vehicle when a driver of the electric vehicle deeply treads an accelerator pedal or completely releases the accelerator pedal is eliminated, and the comfortableness of the driver in the driving process is improved.

The invention relates to an input shaper closed-loop control method based on a chaotic particle swarm optimization algorithm and belongs to the technical field of methods for drive control in the coaxial transmission machine start process. In order to solve the buffeting problem in the coaxial transmission machine start process, closed-loop control is performed on a transmission mechanism with the control method, and the effectiveness and the feasibility of the control method are proved by experimental results. In an offline state, a double-pulse input shaper is optimized through the chaotic particle swarm optimization algorithm, optimization parameters of the double-pulse input shaper are obtained, and then a PD closed-loop actuating mechanism is controlled through the optimized input shaper. The input shaper parameter self-tuning control algorithm based on chaotic particle swarm optimization is provided for solving the buffeting problem in the coaxial transmission printing machine start process. Due to the control, a system can respond fast without vibration while torsional vibration of the system is substantially suppressed.

A motor control device of a vehicle includes a motor and a lock mechanism for locking the rotation of vehicle wheels. The motor control device includes a detection device for detecting release of the lock mechanism, a damping control device for suppressing torsional vibration of a drive shaft, and a current control device for controlling current flowing to the motor on the basis of a motor torque command value set by the damping control device. The current control device channels an excitation current for generating a magnetic flux in the motor on the basis of the detection result of the detection device.

A coolant pump for use with an internal combustion engine having a crankshaft and a camshaft driven by the crankshaft includes a pump housing fixedly mountable to the engine. The pump housing includes an inlet opening to receive coolant and an outlet opening to discharge coolant. An impeller shaft is operatively coupled to the camshaft so as to be rotatably driven thereby. A pump impeller is operatively mounted to the impeller shaft within the pump housing, the pump impeller rotatable to draw the coolant into the pump housing through the inlet opening and discharge the coolant at a higher pressure through the outlet opening. The pump impeller includes first and second shrouds separated by a plurality of vanes. The first and second shrouds and plurality of vanes are configured and positioned such that a resultant thrust load acting on the pump impeller and hence the impeller shaft is approximately zero.

When a gear position at a higher speed range than a “specific gear position at a lower speed range” (e.g., first speed) is determined (when the torsional vibration is difficult to occur), a clutch torque is controlled such that a clutch is in a totally engagement state (a revolution speed Ne of an output shaft of an engine=revolution speed Ni of an input shaft of a transmission). On the other hand, when the “specific gear position at the lower speed range” (e.g., first speed) is determined (when the torsional vibration is easy to occur), the clutch torque is controlled such that the clutch is in the semi-engagement state (Ne−Ni=predetermined positive value A). In the semi-engagement state, a “damping action by a slip on the clutch” is acted on the torsional vibration, whereby the amplitude of the torsional vibration can be reduced.

A first damper mechanism 159 for absorbing and attenuating minute torsional vibration in a damper disk assembly for transmitting torque in a vehicle, has a plate spring 162. The plate spring 162 extends in the rotational direction having main surfaces facing in the radial direction. The plate spring 162 is pushed by the hub 106 in the rotational direction to slide against the intermediate rotating member 110 when the hub 106 and the intermediate rotating member 108 rotate relative to each other, thereby generating friction resistance.

The invention discloses a design method of an SVC (static var compensator) subsynchronous damping controller based on an improved BBO (biogeography-based optimization) algorithm. Through the IBBO (improved biogeography-based optimization) algorithm introducing a cosine migration model, a prematurity judgment mechanism, a mutative scale chaos variation strategy and a repetitive removing operation, based on a mechanism that the IBBO algorithm combines the SVC to restrain SSO (subsynchronous oscillation), the subsynchronous damping controller is subjected to an optimization design. Therefore, the SVC subsynchronous damping controller designed by the method disclosed by the invention can greatly improve themodal damping of torsional vibration of a machine set and effectively restrain the SSO so as to ensure the safe and stable operation of the machine set and a power grid.

A torsional vibration damper equipped clutch (20) for a combustion engine (E) includes a clutch drum (32), coupled with a cutter blade (3) through a drive shaft (6), a clutch shoe (34) connected with a crankshaft (16) of the combustion engine (E) and capable of being connected with the clutch drum (32) by the effect of a centrifugal force. The clutch (20) further includes a flywheel (18) fixed to the crankshaft (16) by means of a nut (19), and a holder (36) connected with the flywheel (18) for relative movement in a circumferential direction through a helical compression spring (50). The clutch shoe (34) is supported by the holder (36), and a stopper structure (56) is provided between the flywheel (18) and the holder (36) for transmitting a rotational force of the combustion engine (E) to the holder (36).

The invention relates to a method for restraining the torsional vibration of a rotor of a motor closed-loop speed control system. The method comprises the following steps: (1) collecting a revolving speed signal of the motor rotor through a signal collecting unit, and enabling the revolving speed signal to pass through a band pass filter unit to extract a torsional vibration component signal of the rotor; (2) enabling the torsional vibration component signal of the rotor to pass through a lead-lag unit to regulate the phase position of the torsional vibration signal, and obtaining an electromagnetic torque component signal being phase-opposite with the torsional vibration component signal of the rotor; and (3) regulating the gain amplification times of a gain amplification unit, adding the electromagnetic torque component signal into a revolving speed feedback point through an amplitude limiting unit to generate an electromagnetic torque component being phase-opposite with the torsional vibration signal of the rotor, and therefore effectively restraining the torsional vibration of the motor rotor and power vibration. According to the method, the divergent torsional vibration of the rotor can be restrained, meanwhile the power vibration due to the torsional vibration of the rotor can also be restrained, and the signal collection is simple and convenient. The method has the advantages of simple structure, lower cost, less regulation parameters, easiness in realization and the like and has a larger promotional value.

A motor control apparatus has an inverter that applies a voltage to an AC induction motor to be driven, a command value calculator that calculates a command value of an AC voltage outputted from the inverter based on a target motor torque of the AC induction motor, and an inverter controller that controls the inverter based on the command value of the AC voltage. The target motor torque of the AC induction motor includes a first target motor torque and a second target motor torque. A high speed response is required in the first target motor torque in order to at least suppress torsional vibration. The second target motor torque is a lower speed response than the first target motor torque. Delay processing is carried out for the second target motor torque.

A pendulum vibration damper in which a retainer is prevented from being moved or tilted in an axial direction. In the pendulum vibration damper, a restriction member formed on any one of the retainer and an inner face of the casing to be brought into contact to the other one of the retainer and the inner face of the casing when the retainer is moved or tilted in an axial direction of the rotary disc. A clearance between the casing and the rolling mass in the axial direction is shorter than a thickness of the retainer in the axial direction.

The invention discloses a control method and system for transmission chain torsional vibration caused by periodic excitation. The method comprises the steps that A, the rotating speed of a wind wheel of a fan is measured, and a uniform pitch angle set value beta ref based on the measured rotating speed and a rotating speed set value; B, the uniform pitch angle set value is distributed to each paddle so as to obtain a pitch angle set value beta iref=Ki beta ref of the independent change of each paddle, wherein the weight coefficient Ki is determined by azimuth angle feedback of each blade; C, the input torque of a transmission chain of the fan is measured, the frequency doubling amount of the rotational frequency of the wind wheel is obtained through analysis, and a fine adjustment amount delta beta i of each pitch angle is obtained based on three times of the frequency doubling amount and six times of the frequency doubling amount; and D, the expected pitch angles of the blades are obtained according to the pitch angle set value and the pitch angle fine adjustment amount of each paddle, and each blade is controlled according to the expected pitch angles. The method and the system have the advantages that the pitch angle fine adjustment amount is added on the basis of the independent variable pitch control based on the azimuth angle feedback, and therefore the transmission chain torsional vibration caused by the periodic excitation can be better controlled.

A pedestrian conveyor includes a torsional vibration damper system, the torsional vibration damper system including a shaft, a cylindrical housing attached to the shaft and being configured to dampen vibrations of the shaft, a first gear, and a second gear.