135 results about "Oscillation phenomenon" patented technology

The invention relates to a three-freedom-degree constant speed decoupling space robot active spherical wrist and a universal compliant control method. The offset mode that the included angles are formed among rotation plane normal and rotating shafts is adopted for both an upper hemisphere rotating body and a lower hemisphere rotating body. The intersection point of the two rotating shafts of the upper rotating body and the lower rotating body is the sphere center of hemispheres of the upper rotating body and the lower rotating body, the intersection point of the two rotating shafts coincides with the rotating center of an inner ball cage universal joint and the rotating center of an outer ball cage universal joint respectively, and then constant speed decoupling of three input movements is achieved; the output end of the outer ball cage universal joint is connected with a shaft neck of the upper rotating body through a bearing in a suspension mode, three absolute corner coded discs are connected with the upper rotating body, the lower rotating body, a motor conducting spinning motion, and the output end of a speed reducing system respectively, a six-dimensional ATI sensor is installed at the output tail end of the wrist, and a wrist universal compliant follow-up control mode is achieved by a rotating joint of an upper hemisphere, a rotating joint of a lower hemisphere and a joint conducting spinning motion through a system friction force compensation technology. The three-freedom-degree constant speed decoupling space robot active spherical wrist and the universal compliant control method are accurate in locating, stable in movement, and capable of avoiding oscillation phenomena of movement coupling and mechanical arms and effectively relieving mechanical interference in a spherical wrist full compliant mode.

A solid state igniter device for hot restrike of discharge lamps with an associated supply circuit. The ignitor device comprises a primary circuit with at least one solid state switch element controlled to switch to induce in the primary circuit a controlled oscillation phenomenon at a frequency greater than a megahertz and a secondary circuit including a resonant circuit with a high quality factor Q (at least 100), capable of resonating and producing a pulse signal for striking the discharge of the lamp, controlled through the controlled oscillation phenomenon produced in the primary circuit. A control unit acting on the switch element controls the oscillation phenomenon in a pulse mode as a function of the characteristics of the lamp and the power supply, wherein the control unit induces the controlled oscillation phenomenon for a predetermined time duration a programmable number of times in a predetermined time interval.

The invention relates to a method for predicting a fluid-solid coupled characteristic value of an elastic hydrofoil and belongs to the technical field of turbomachinery simulation. The method comprises the steps of establishing a two-dimensional drainage basin-hydrofoil geometric model, dividing the gridding of a two-dimensional drainage basin, establishing a computational fluid mechanical model, calculating an initial steady flow field value and an unsteady flow field fluid-solid coupled value, and then performing after-processing on the calculation results to obtain the dynamic change process of the deformation of the flow field structure and the hydrofoil with time. The method for predicting the fluid-solid coupled characteristic value of the elastic hydrofoil has the advantages that the influence of an added mass effect on flowing is taken into account so that the stability of value calculation and the reliability of a numerical prediction result are improved, quick high-accuracy numerical prediction on an oscillation phenomenon induced by flowing around the elastic hydrofoil can be realized, and the flexibility of selection of numerical computation methods can be enhanced by virtue of secondary development of computational fluid mechanical software in combination with an embedded fluid-solid coupled algorithm.

The invention relates to a motion control method of a double-wheel differential type robot, which is technically characterized in that a body coordinate system xoy is established in the world coordinate system XOY by taking the geometric center of a robot as the origin of coordinates; and motion control method for the double-wheel differential type robot is based on kinematics, aims at the most fundamental and most important two motions among all the motions of the wheeled robot, i.e. the in-situ rotating motion and the moving-to-fixed-point motion of the wheeled robot, and realizes the control of the two motions. All the complicated motions of the double-wheel differential type robot can be composed of the two fundamental motions. By reasonably improving the linear speed function in the control method based on the error ratio and simultaneously combining the chord tangent method, the invention realizes the integrated control on the moving-to-fixed-point motion of the robot. The integrated control greatly gives play to the respective advantages of the two methods, and avoids the effects of the respective defects on the robot motion. The invention also provides a resolution strategy corresponding to the cyclic oscillation phenomenon.

The invention provides a steel plate width control method, which comprises the following steps of: determining a mathematical model based on a rough rolling mathematical model setting and broadening coefficient according to a width difference between the width of an incoming slab and the width of a finished strip steel, namely a side pressure quantity, and adding a broadening compensation coefficient of between -0.1 and -0.65 into the mathematical model; and during the rolling process, adjusting the broadening compensation coefficient twice to thrice according to the practical rolling state and the strip steel width detection result, wherein the adjusting amplitude of each time is 0.1. Therefore, the method basically eliminates the steel plate width oscillation phenomenon, reduces the strip steel blockade rate generated by excessive width difference by 0.011 percent, improves the width precision qualification rate of the strip steel by 4.2 percent, and has quite remarkable economic benefit.

The invention is suitable to the field of electrical switches and switch power-supplies, and provides an insulation driving circuit of a power switch tube. According to the invention, on the basis of the insulation driving circuit of the traditional power switch tube, the reliability and stability of the insulation driving circuit in conduction and disconnection are improved through increasing the gate filter capacitance of the power switch tube and correspondingly accelerating disconnection of a discharge path; the acceleration for the disconnection of the discharge path works when the gate filter capacitance is greater, the gate filter capacitance is subjected to rapid discharge when in disconnection, and the switch oscillation phenomenon of MOSFET (metal-oxide-semiconductor field effect transistor) caused by slow decrease of a gate voltage is avoided; when the gate filter capacitance is greater, the gate voltage is very stable, which is very good for the MOSFET; and when an input signal is at a close state, through accelerating the disconnection of the discharge path, a gate of the MOSEFT is discharged all along, thus the gate voltage cannot be accumulated, and the error conduction of the power switch tube which is required to be turned off is avoided.

The invention relates to a fiber distributed monitoring method and device for the safety monitoring of a long-distance pipeline. By using a fiber Sagner interferometer fiber consisting of a laser, a 2 is multiplied by 2 coupler and two optical fibers arranged in parallel to the long-distance pipeline, the invasion or leakage events are detected based on the interference signal caused by oscillation phenomenon. An optical fiber delay line is preset at the emergence end of either of the two optical fibers under the condition that the two optical fibers oscillate at the same time. An optical fiber delay line is preset at the farthest end under the condition that either of the two optical fibers oscillates. The interference factor is compensated by means of periodic narrow pulses, record light source fluctuation and equilibrium demodulation, thereby realizing the long-distance pipeline safety detection with high sensitivity. The invention also uses a computer database to store and sort data, analyze the event type and give alarms of different levels. The invention utilizes low-cost mobile modules to combine a plurality of independent devices distributed along the long-distance pipeline and thus to form the long-distance wireless monitoring system, and realizes the roll call measurement, periodic measurement and data upload.

The invention discloses a method for suppressing the limit cycle of an inclination angle control system of an aircraft with parameter uncertainty. The method comprises the following main steps of: step 1, analyzing and establishing a model of the inclination angle system of the aircraft; step 2, analyzing scanning functions of a non-linear section and an oscillation phenomenon of the limit cycle; step 3, designing a controller of the inclination angle system of the aircraft with the parameter uncertainty; step 4, inspecting the performance of the controller; and step 5, ending the design. With the adoption of the method, not only is the oscillation of the limit cycle of the aircraft suppressed, but also the parameter uncertainty is overcome, and furthermore, the rapid and precise tracking to the inclination angle of the aircraft is realized. The method has better practical value and good application prospect in the technical field of automatic control.

The invention belongs to the field of protein secondary structure prediction methods, relates to a BP neural network training and prediction method used for protein secondary structure prediction and solves the problem of bad prediction effect of the protein secondary structure. The BP neural network training and prediction method comprises the steps of firstly selecting a group of training sample sets with [alpha]-helix, [beta]-sheet and coiling structures accounting for normal proportions from PDB, coding an amino acid sequence of a protein and regarding the coded amino acid sequence of the protein as a network input, and regarding a secondary structure of the corresponding amino acid as a network output; optimizing based on a gradient method, introducing a learning rule which is attached with a momentum item and a self-adaptive learning rate to avoid an oscillation phenomenon and prevent from being trapped in a local minimum value; adopting a six-bit input coding way and a sliding window technology in an input layer, setting a hidden layer structure based on an experience formula and the size of a sliding window; and outputting and predicting classification of the protein secondary structure by an output layer based on a DSSP algorithm.

The invention discloses a temperature adjusting method which comprises the following steps that: current temperature value is measured and deviation e is obtained according to the current temperature value; when the absolute value of e is more than a second deviation threshold and is less than or equal to a first deviation threshold, P, I and D is adjusted and the proportional action and integral action in control is increased while derivative action is weakened; when the absolute value e is more than or equal to zero and is less than or equal to the second deviation threshold, P, I and D is adjusted and the proportional action, integral action and derivative action in control is weakened; according to a third deviation threshold A and the deviation e, integral action intensity factor is adjusted; according to the adjusted P, I, D and integral action intensity factor, the increment of control quantity is obtained; moreover, temperature is adjusted according to the increment of control quantity. The invention also discloses a temperature adjusting device. In addition, the invention can effectively reduce the overshoot and oscillation phenomena during temperature control.

The invention relates to signal processing and aims at providing a micro-spectrometer signal denoising method based on stable wavelet transform. The method includes subjecting a spectrum signal generated by a micro-spectrometer to stable wavelet decomposition to obtain a detail coefficient and an approximation coefficient of a stable wavelet of the spectrum signal; using methods of a soft threshold function and a multi-resolution heuristic threshold selection rule to transform the detail coefficient so as to remove noises and saving the detail coefficient as a new stable wavelet detail coefficient; and subjecting the new detail coefficient and the prior approximation coefficient to stable wavelet inverse transformation to obtain a denoised micro-spectrometer spectrum signal. The micro-spectrometer signal denoising method is invariant in translation and capable of effectively inhibiting a Gibbs oscillation phenomenon and guaranteeing facticity of signals, fake peaks can not occur to line spectrum signals, and geometrical characteristics of the denoised spectrum signal are identical to those of original signals; and compared with other threshold selection methods, the micro-spectrometer signal denoising method is capable of obtaining a higher signal to noise ratio and better denoising continuous spectrum signals and the line spectrum signals.

The invention relates to the field of molten iron pretreatment desulfurization processes, in particular to a slag conglomerating and skimming method and a device. The slag conglomerating and skimming method sets a traveling wave magnetic field; the phase of the magnetic field is controlled to enable the moving direction of molten iron driven by the traveling wave magnetic field to point to a ladle port; the traveling wave magnetic field enables the molten iron to flow to the ladle port under the effect of electromagnetic force, so that molten iron slag is conglomerated in the ladle port; and when the conglomerated molten iron slag is higher than the ladle port, the molten iron slag can overflow a ladle to enter a slag receiving tank so as to realize the ladle slag skimming. The slag conglomerating and skimming device comprises an electromagnetic winding and the slag receiving tank; the electromagnetic winding is arranged above the ladle; the magnetic force line of a magnetic field generated by the electromagnetic winding is pointed to an area of the ladle port; and the slag receiving tank is arranged below the ladle port. The slag conglomerating and skimming process is finished under non-contact conditions without generating the molten iron oscillation phenomenon; the molten iron nearly has no loss; the precise slag conglomerating and skimming operation is realized without polluting the molten iron; and the ton steel energy consumption can be reduced.

Provided is a magnetic belt guided AGV tracking control method based on auto-disturbance-rejection control. Firstly, a magnetic belt guided AGV tracking control system model is established. Secondly, the deviation distance of a magnetic guided sensor under different postures of the vehicle is measured to describe output variables required by a control system, and a measurement error in the actual measurement process and a description error are taken as one part of system disturbance. Thirdly, for a second-order model of the magnetic belt guided AGV tracking control system, an auto-disturbance-rejection controller based on an extended state observer is designed, and the system disturbance is estimated and subjected to freeforward compensation through the extended state observer, thus eliminating the impact of the system disturbance on system performance. The magnetic belt guided AGV tracking control method of auto-disturbance-rejection control solves the contradiction between the fastness of the magnetic belt guided AGV tracking and overshoot control, effectively suppresses the oscillation phenomenon in the tracking process and improves the anti-disturbance capacity of the system.

The invention discloses an exposure parameter adjusting method, device and readable medium, and belong to the technical field of the image processing. The method provided by the invention comprises the following steps: acquiring an exposure evaluation value of the current frame image, and determining an exposure state of the current frame image according to the exposure evaluation value; acquiringthe exposure state of the former frame image, the exposure parameter adjusted based on the exposure state of the former frame image, and an adjusting direction; determining the exposure parameter adjusting type according to the exposure state of the current frame image and the exposure state of the former frame image; and adjusting the current exposure parameter according to the exposure parameter adjusting type, the exposure parameter adjusted based on the exposure state of the former frame image, and the adjusting direction. The current exposure parameter is adjusted by using the above method, the oscillation phenomenon is effectively prevented in comparison with the way of adjusting the exposure parameter only through the exposure state of the current frame image in the prior art, andthe image quality is further guaranteed at the same time.

The invention relates to a DC power supply controlled by an energy closed loop, comprising a main circuit and a control circuit. The main circuit is a standard Buck circuit. The control circuit comprises: Inductance Current Detection Circuit, capacitance voltage detection circuit, output current detection circuit, Circuit for calculate energy storage of desired capacitance, an expected inductanceenergy storage calculation circuit, an expected load energy consumption calculation circuit, an expected total energy calculation circuit, an actual inductance energy storage calculation circuit, an actual capacitance energy storage calculation circuit, an actual load energy consumption calculation circuit, a load identification circuit, an actual total energy calculation circuit, an operation circuit, a controller circuit, and a PWM signal circuit. As that invention weaken the sensitivity of the dynamic performance of the output of the power supply to the value of the control parameter, the complexity of the controller parameter design is reduce, and the overshoot and oscillation phenomena of the voltage and the current are restrained, at the same time, the optimization of the dynamic adjustment time is realized.

Following structures are adopted in the electromotor of rare earth permanent magnet: slotted solid pole, extension duplex start-up cage, pole core with large polar arc, large even air gap or heteropic air gap, small rectangle block of permanent magnet embedded to slot. Comparing with conventional permanent magnet motor of laminated pole, the basic series of permanent magnet synchronous motor possesses advantages: obviously raised starting torque 2.2-3.7, and asynchronous motor as 1.8-2.0; raised capability rank, for example it is possible to use 22kW permanent magnet motor to replace asynchronous motor in 30kWY series so as to obtain energy saving effect; start up current 5-7 times of the disclosed motor is smaller than start up current of asynchronous motor; moreover, shorter start up current, and no severe oscillation phenomenon. The basic series also overcomes difficult problem of demagnetization of neodymium - iron - boron permanent magnet electromotor.

The invention provides a modular multilevel converter (MMC) contained direct current power transmission system's current oscillation suppression damping control method, comprising the following steps: creating an MMC simplified and equivalent model; selecting a damping controller structure; determining the final expression form of the damping controller and configuring the parameters for the damping controller; based on the final expression form of the damping controller and the direct current of the outlet of the current converter, obtaining the damping compensation voltage; transmitting the damping compensation voltage to a current converter valve based controller and obtaining the corrected bridge arm reference voltage of the MMC so as to realize the suppression on the current oscillation components. According to the technical schemes of the invention, it is possible to effectively suppress the oscillation phenomenon of an MMC type direct current power transmission system and the insecurity of the system.

The invention belongs to an optical design technique, and relates to a depolarization light path design method of a high-precision fiber gyroscope and a depolarization light path design system. The depolarization light path design method of the fiber gyroscope disclosed by the invention comprises an online measurement module of a wide-spectrum light source spectrum, a calculation module of a light source coherence function, a detection module of coherence function correlation peak and decoherence length and a depolarization scheme design module. The depolarization light path design method comprises the following steps: firstly, judging a correlation peak position of a light source and calculating the light source decoherence length by adopting a corresponding algorithm by online measurement of the spectrum data of each light source; providing design parameters of a depolarization scheme light path, wherein the design parameters comprise a length requirement on each polarization maintaining fiber in a depolarizer, a length requirement on a Y-waveguide tail fiber, and a shaft angle requirement of fusion of the polarization maintaining fiber in the depolarizer. By adopting the design method and the design system, accurate parameters are provided for the structure design of the depolarization light path, the depolarization light path capable of effectively eliminating a gyroscope zero oscillation phenomenon is designed, the product quality and the production efficiency are improved, and the design method and the design system have good practical application values.

The invention discloses a hyper-chaotic signal source circuit of a hidden Lu system based on a memristor. A memristive term is added to a first equation of the original Lu system, and a linear feedback term and an external excitation term are added to a second equation. The system circuit comprises a memristor equivalent implementation circuit and an oscillating system. After the respective same ports of the memristor equivalent implementation circuit and the oscillating system are sequentially connected, the memristive system implemented does not have a balance point, can generate hidden oscillation phenomena of point attractors, periodic limit cycles, quasi-periodic limit cycles, chaotic attractors and hyper-chaotic attractors, etc., and can generate a hidden multi-attractor coexistencephenomenon of different periodic limit cycles or weak chaos and periodic limit cycles of a topological structure under different initial conditions, indicating that signals generated by a signal source have richer and more complex nonlinear dynamic characteristics. The system circuit facilitates circuit implementation and experimental observation, and is a new key signal generation circuit for chaotic secure communication.

The invention discloses a hidden multi-attractor generating circuit based on a non-equilibrium point memristive system realized by replacing a three-dimensional self-excited oscillation system with a voltage-controlled memristor to realize the linear coupling resistance at the input end of the integration circuit, including two parts: The voltage-controlled memristor equivalent realizes the circuit a and the three-dimensional self-excited oscillation system b; where the same ports of the circuit a and the circuit b are connected in sequence, the realized memristive system can present periodic limit cycles, quasi-periodic limit cycles, and chaotic attractors and hidden oscillation phenomena such as coexisting attractors. The circuit system is easy for numerical simulation, circuit simulation and experimental observation, and plays a great role in promoting the research and development of hidden multi-attractors.

The invention discloses an over-temperature protection circuit. The over-temperature protection circuit comprises a constant current generation circuit, an output control circuit, and an output shaping circuit. An NPN transistor Q0 is employed as a control switch tube. A hysteresis control tube M4 can be employed as an NMOS tube and also can be employed as a PMOS tube. Temperature hysteresis is achieved through introduction of an extra current after over-temperature and a hysteresis temperature magnitude can be arranged through adjustment of a ratio of width to length of an M4 tube. The over-temperature protection circuit is simple in structure, does not need any high-precision voltage comparators, the used device number is low, the output precision is high, a turn-off signal can be generated at a thermal turn-off temperature threshold point accurately, debugging is convenient, the over-temperature protection circuit has a temperature hysteresis function, the hysteresis temperature can be arranged flexibly, heat oscillation phenomena are prevented, and the over-temperature protection circuit is suitable for usage of chips of a power supply and a driving circuit and the like.

The invention discloses a method for achieving an anti-snaking broadband energy absorption mechanism and an optimal configuration method for the parameters of a bogie. According to the method and the optimal configuration method, a dynamic design method is mainly applied, and lead-lag correction of unstable snaking oscillation phenomena of the bogie is achieved in a self-adaptive control manner; an anti-snaking redundant design form of an ICE3 prototype is borrowed, the anti-snaking broadband energy absorption mechanism is achieved through combination application of novel anti-snaking vibration reducers, and the method and the optimal configuration method are simple and applicable; and an anti-snaking soft constraint or anti-blocking technology is borrowed, the hydraulic rigidity is properly reduced, and rheology nonlinear influences are avoided. By means of the method and the optimal configuration method, the design defects of the ICE3 bogie prototype are overcome, a high-speed-rail passenger-dedicated development manner is gradually changed, and then the rate of return on investment is increased; in addition, the adaptability and the friendliness to track lines are improved, and the railway construction investment cost can be saved; and meanwhile the robustness of perturbation or disturbance of natural factors is improved, and particularly when the method and the optimal configuration method are used for mountain lines, and the structural technical service cost can be obviously reduced.

The invention relates to the field of photovoltaic power generation, in particular to an adaptive inertial weight chaotic particle swarm optimization (ACPSO) algorithm. The algorithm utilizes segmented Logistic mapping with higher efficiency than general Logistic mapping to generate a chaotic sequence to initialize the positions of particles, so that the diversity of global search is ensured; then, a particle swarm algorithm is optimized by adopting an adaptive inertia weight, so that the tracking speed of the maximum power is increased; and finally, if the judgment algorithm falls into precocity, performing extreme value disturbance on the particle optimal position and the global optimal position at the same time. Compared with single extreme value disturbance, the method can enable the algorithm to jump out of local optimum faster. According to the algorithm, the maximum power point can be tracked more quickly and effectively in real time according to sunlight changes, the system works near the maximum power point, meanwhile, the oscillation phenomenon of the system at the maximum power point is reduced, and the utilization rate of a photovoltaic array is increased.

The invention provides a converter three-grade signal protection circuit. The protection circuit comprises a sensor, a hardware excess protection circuit, an FPGA protection circuit, a DSP pulse blocking circuit, a PWM driving circuit and an IPM power module. The FPGA protection circuit is used for generating a fault pulse blocking signal according to an over-current fault signal, an overvoltage fault signal, an upper bridge arm fault signal and a lower bridge arm fault signal and blocking converter pulse signals of an FPGA, a DSP and the PWM driving circuit. The DSP pulse blocking circuit is used for setting six paths of PWM trigger pulse signals output to the FPGA to a high-resistance state after receiving the fault pulse blocking signal. The technical problem in the prior art that over-current oscillation may easily occur to a converter system to cause damage to an IPM is solved, and the over-current oscillation phenomenon of internal protection of the converter is restrained effectively.

The invention discloses a driving mechanism, particularly a driving mechanism for a nut rotary type long lead screw, which comprises a long lead screw and a nut with a thread. The two ends of the long lead screw is fixedly supported on a support; the nut with the thread which is matched with the long lead screw is connected with a rotary driving mechanism; the outer side of the nut with the thread is provided with a fixed sleeve which is connected with a connecting plate; a bearing is arranged between the fixed sleeve and the nut with the thread; and the rotary driving mechanism is arranged on the support which is connected with the fixed sleeve or the connecting plate. During use, the long lead screw does not rotate, the nut with the thread is driven to rotate by a power plant to enable the nut with the thread to move relative to the long lead screw, so that the nut with the thread drives other components to move, the problem of large deflection caused by the rotation of a long ball screw is solved, and the adverse factors such as the restriction on the critical rotational speed of the ball screw are avoided. Thus, when the length of the lead screw is longer and the movement speed is higher, oscillation phenomenon cannot occur and the lead screw can move steadily without influencing other components, which improves the running accuracy of the equipment.