77 results about "Stability margin" patented technology

Belongs to the technical field of motion control of foot-type robots, and particularly relates to an anti-interference whole-body control method and system for a quadruped robot based on stability margin perception. The expected joint position, speed and foot end contact force are obtained through nonlinear model predictive control NMPC; a whole body controller WBC based on hierarchical quadratic programming calculates a joint driving torque according to the task priority; according to the joint position, the speed and the torque fed back by the driver and a robot dynamic model, estimating the foot end contact force; calculating resultant force which causes instability of the robot relative to each support polygon side line of the robot; projecting the resultant force, and calculating an included angle between the projection force and the vertical direction; calculating a compensation acceleration through a PI controller; and the compensation acceleration is used as a part of a fuselage linear acceleration task in the WBC, so that the anti-interference capability of the robot is improved. The method is used for solving the problems that in the prior art, the stable state of the quadruped robot cannot be effectively sensed, and an anti-interference control strategy cannot be rapidly generated according to the stable state.

The invention discloses an electric power system transient stability state and stability margin evaluation method, device and equipment based on Grapher multitask learning and a medium, and relates to the technical field of electric power, and the method comprises the steps: carrying out the standardization of node features corresponding to a bus and edge features related to a power transmission line and a transformer branch, and obtaining standardized features; determining a dichotomy label based on a power angle difference between the generators after a fault occurs, determining a regression label based on a difference between a generator rotor angle trajectory and an inertia center trajectory, and determining a target Grapher multi-task learning model by using the standardized features, the dichotomy label, the regression label and an initial Grapher multi-task learning model in combination with a multi-task loss function; and determining a transient stability state and a transient stability margin of the power system based on the real-time operation data and by using the target Grapher multi-task learning model. Therefore, the accuracy of transient stability evaluation is improved.

The invention relates to the technical field of floating fans, in particular to a parameter tuning method suitable for a multi-tuned mass damper of a floating fan, which sequentially comprises the following steps of: establishing a system dynamics model; defining an optimization variable and a constraint range; constructing a comprehensive fitness function; initializing a grey wolf population and algorithm parameters; executing a grey wolf position optimization updating mechanism; setting convergence judgment conditions; and outputting the optimal TMD parameter combination. According to the method, structural dynamic characteristics and an intelligent algorithm strategy are fully fused, particularly, spatial arrangement coordinates of the TMD are brought into an optimization variable domain, collaborative design of tuning parameters and arrangement space is achieved, the method is different from a single-parameter or fixed-point optimization mode, the limitation of artificial experience layout is avoided, overall suppression of structural multi-order modal response is achieved, and the method is suitable for large-scale popularization and application. The damping capacity and the stability margin of the fan structure under wind wave flow coupling excitation are improved, cross-modal and multi-source vibration cooperative treatment is achieved on the system response coordination and control strategy level, and the method has the adaptability to offshore wind power scenes.

The invention provides a stability margin calculation method of a new energy station grid-connected system, a terminal and a storage medium. The method comprises the following steps: acquiring inverter output impedance and power grid side equivalent impedance of an initial new energy station grid-connected system under multiple working conditions; taking the ratio of the output impedance of the inverter to the equivalent impedance of the power grid side under the same working condition as an open-loop transfer function, and determining a gain margin and a phase margin of the new energy station grid-connected system under each working condition based on the open-loop transfer function under each working condition; determining the weakest working condition of the new energy station grid-connected system based on the gain margin and the phase margin of the new energy station grid-connected system under each working condition; and under the weakest working condition, based on the gain margin and the phase margin of the new energy station grid-connected system under different numbers of inverters connected in parallel, the maximum capacity expansion number is determined. According to the method, accurate quantification of the capacity expansion limit is realized, the system stability is ensured, and the capacity expansion potential of the station is fully excavated.

This application belongs to the field of aero-engine design and presents a design method for high-altitude starting fuel supply patterns based on the low-altitude starting fuel supply patterns. It involves first conducting high-altitude bench tests on the starter to obtain the power reduction characteristics of the starter at different altitudes. Then, based on the power balance equation, the acceleration time of the starter from rotor standstill to idle speed is determined. Finally, based on the acceleration time of the starter from rotor standstill to idle speed, the time allocation of the three starting stages of the starting process—starter engagement, starter disengagement, and engine starting—is performed to obtain the high-altitude starting fuel supply pattern. This method enables rapid and accurate design of the high-altitude fuel supply pattern, taking into account the engine's stability margin design in high-altitude areas, starter power characteristics, and the attenuation characteristics of starter power with increasing altitude, thus avoiding abnormal phenomena such as engine cold suspension and overheating. Furthermore, it can be based on ground starting data statistics, achieving better design compatibility and reducing debugging work.

The invention discloses a posture adjustment and turnover control method and system of an adjustable platform. The method comprises the following steps: firstly, collecting mounting positions and the like of a plurality of supporting units of a platform, calculating effective supporting length and determining a current platform posture and a supporting polygon; calculating a centroid projection trajectory within a predetermined overturning angle range by using the overturning shaft and the centroid position of the workpiece, forming stability margin distribution according to the minimum distance of the centroid projection to the boundary of the support polygon, determining a target platform attitude meeting a stability threshold, and reversely solving the target telescopic length of each support unit; establishing a corresponding relation between the overturning angle and the telescopic length of the driving mechanism according to the installation geometric parameters of the overturning driving mechanism, and generating an overturning angle track; in the overturning process, the current overturning angle is determined by measuring the telescopic length of the driving mechanism, and a corresponding control section is selected to generate an overturning control instruction. According to the invention, the coordination control of the platform posture adjustment and the overturning process is realized, and the stability and the safety of the overturning operation are improved.

This application relates to the field of new energy technology, providing a control method, device, system, storage medium, and program product for an underwater compressed air energy storage system. It can employ a matching control strategy based on the actual operating conditions of the underwater compressed air energy storage system to ensure the reliability of its actual operation. This application involves obtaining the safety domain boundary of the underwater compressed air energy storage system; obtaining the current stability margin of the underwater compressed air energy storage system based on the distance between the current operating point of the system and the safety domain boundary; determining the current safety state of the underwater compressed air energy storage system from multiple preset safety states based on the current stability margin; and controlling the operation of components in the underwater compressed air energy storage system according to a control strategy matched to the current safety state.

This invention discloses a method and system for frequency oscillation transfer analysis under multi-machine islanding. The method includes: establishing a transfer function; substituting the operating parameters of each operating condition into the transfer function; if stable, determining whether it is stable; if stable, it indicates that the system on the second VSG side is stable; if unstable, jumping to S3.1 to determine the cause of frequency oscillations on the second VSG side and the first VSG side; if unstable, it indicates that the frequency oscillations on the second VSG side are caused by insufficient stability margin of the second VSG side itself. The advantage of this invention is that it more accurately explains the cause of low-frequency oscillations in the system, thereby guiding the design of virtual synchronous machine controller parameters.

The invention discloses a parameter estimation and adaptive control method, device, medium and product of a high-performance aircraft pitch angular velocity control system with stability margin self-configuration, and relates to the field of aircraft control, the method comprises the following steps: collecting the pitch angular velocity of an aircraft and the deflection angle of an elevator in real time, and calculating a tracking error; constructing a relation equation of system parameters and stability margin based on a PI controller, and performing approximate simplification by adopting a numerical approximation method; estimating system parameters and time delay on line by adopting an approximate nonlinear least square algorithm; and substituting the target stability margin, the system parameter estimation value and the time delay estimation value into a system frequency domain characteristic equation for solving to obtain a proportional gain and an integral time constant of a PI controller, and adjusting an elevator deflection angle of the aircraft in combination with a tracking error so as to control the pitch angular velocity of the aircraft. According to the invention, the autonomous configuration of the stability margin is realized, and the stability, robustness and dynamic adaptation capability of the control system are improved.

The application discloses a grid-construction converter parallel system transient stability evaluation and enhancement method, and belongs to the technical field of power system transient stability evaluation; the evaluation method comprises the following steps: a differential-algebraic model of a hybrid system is established and is converted into a state space form, time variables are eliminated by performing quotient operation on equations to establish a time domain separation reduced-order model; a multivariable alternating iteration algorithm is used to solve implicit space trajectory integral equation groups, and a generalized transient kinetic energy is used to find a farthest point of a phase orbit, so that instantaneous generalized acceleration torque at the point is calculated to quantitatively evaluate transient stability margin of the system. The enhancement method comprises the following steps: a frequency deviation signal of a local phase-locked loop of the grid-construction converter is collected, and an active current reference value is dynamically reduced by a feedback controller to adjust output current. The application breaks through the order limitation of a traditional equal-area criterion, realizes accurate evaluation of a high-order hybrid system, and the control strategy can spontaneously reduce acceleration torque without station communication, thereby improving system synchronous stability.

The application discloses an active damper control method based on oscillation risk assessment, and relates to the technical field of new energy power generation systems.The control method comprises four parts: an inverter conventional control part, an oscillation risk assessment part, a stability margin improvement part and an oscillation monitoring and instability recovery control part.The inverter conventional control part is the basis of the active damper control and runs through the whole control stage, and the other three control parts cyclically act in sequence to ensure the stable operation of the inverter system, assess the oscillation risk of the system through current relation, and thus do not need voltage information, thereby reducing the calculation burden of the controller, improving the stability margin of the system before the system is unstable, and improving the stability margin to a set value.

The application relates to a rear wheel steering control method based on multi-source disturbance generalized stability margin and multi-target elastic constraint, which collects vehicle dynamics state data, driver operation behavior parameters and vehicle-road environment information; in a multi-source disturbance generalized stability margin calculation unit, a vehicle-road environment uncertainty multi-source disturbance excitation model and a driver expected steering characteristic model are fitted to obtain amplitude and phase generalized stability margin; in a limit stability influence law analysis unit, vehicle-road safety evaluation indexes, limit generalized stability analysis results and driver comfort evaluation indexes are calculated; in a multi-target elastic constraint optimization unit, a rear wheel steering vehicle multi-target elastic constraint model is established to obtain vehicle-road steering characteristic prediction results, man-machine front and rear steering cooperation instructions and critical stability domain widening control amounts; rear wheel steering angle control signals are output through a line control rear wheel steering high-order control unit. Compared with the prior art, the application has the advantages of high cooperation, safety and stability.

The present application belongs to the field of engine design technology, and specifically relates to a method for determining the flight envelope of an aircraft turbofan engine. The method mainly includes: step S1, obtaining the load spectrum of the power extraction of aircraft accessories within the full envelope range and the comprehensive distortion index allowed by the engine inlet; step S2, determining the speed of the compression component of the turbofan engine when the engine stability margin is weakest; step S3, determining the stable working boundary of the engine after power extraction based on the speed of the compression component when the engine stability margin is weakest. The present application obtains the speed of the critical distortion index of the engine under different altitudes and different speed conditions through pressure distortion tests, thereby determining the flight envelope of the engine under the influence of actual power extraction, greatly improving the engine aerodynamic stability evaluation method, thereby giving the power extraction limit within the envelope range, and avoiding problems such as engine surge.

The application provides a method and system for evaluating the stability margin of a long-distance retrograde orbit spacecraft. First, the current orbit state information of the target spacecraft is obtained. Then, based on the evaluation allowed time range, evaluation time interval, speed error size range and speed error size interval, an error parameter combination set is constructed. Next, based on the current orbit state information and the error parameter combination set, the stability evaluation parameters and the eclipse evaluation parameters corresponding to the error parameter combination are determined through a high-precision ephemeris model. Second, based on the stability evaluation parameters and the eclipse evaluation parameters, the target error parameter combination is determined. Finally, the stability margin is determined based on the target error parameter combination. This method combines the characteristics of long-distance retrograde orbits, engineering application requirements and the influence of eclipses, and selects parameters through the error parameter combination set to determine the stability margin. In this way, the efficiency and accuracy of determining the stability margin of the spacecraft can be effectively improved.

The invention belongs to the field of airborne power system design, and particularly relates to a stability constraint method for an MEA variable-frequency alternating-current power system. The method comprises the following steps: firstly, establishing a port impedance / admittance model of each device in a system; secondly, analyzing the stability of each subsystem, and redesigning if the stability margin does not meet the requirement; then, on the premise that all subsystems are stable, the overall stability of the system is analyzed according to a generalized Nyquist stability criterion; if the whole system is unstable or underdamped, quantitatively identifying a high-influence negative subsystem with the maximum stability deterioration degree in a mode of setting admittance of a load-side subsystem to be zero; and finally, the stability margin of the high-influence negative subsystem is improved by redesigning the high-influence negative subsystem. The MEA variable-frequency alternating-current power system is ensured to have enough stability margin in the design stage, so that the stability problem is avoided.

This invention relates to the field of aerodynamic design technology for multi-stage axial compressors, and discloses a design method and system for passive stability enhancement of a multi-stage axial compressor through self-circulation. By calculating the aerodynamic performance of the multi-stage axial compressor and evaluating engine stability, the method identifies operating conditions where the multi-stage axial compressor has insufficient stability margin. Unsteady flow field simulations are then conducted under these conditions to determine the first stage stall. For the first stage rotor tip stall, a self-circulating casing is used for passive stability enhancement of the multi-stage compressor. The self-circulating casing structure is derived from sensitivity analysis of its design parameters, selecting the optimal design parameters to ensure an increase in the stability margin of the multi-stage axial compressor across the entire speed range. This satisfies the stability margin requirements of multi-stage axial compressors and avoids the problem of insufficient stability margin in high-load multi-stage axial compressors across the entire operating speed range.

The application discloses a power system transient stability state and stability margin evaluation method and device based on Graphormer multi-task learning, equipment and medium, relates to the electric power technical field, including: the node characteristics corresponding to the bus and the edge characteristics related to the power transmission line and the transformer branch are standardized to obtain the standardized characteristics; determine the binary classification label based on the power angle difference between each generator after the fault occurs, determine the regression label based on the difference between the generator rotor angle trajectory and the inertia center trajectory, utilize the standardized characteristics, the binary classification label, the regression label and the initial Graphormer multi-task learning model, and determine the target Graphormer multi-task learning model in combination with the multi-task loss function; determine the transient stability state and the transient stability margin of the power system based on the real-time operation data and by utilizing the target Graphormer multi-task learning model. To improve the accuracy of transient stability evaluation.

The invention discloses a power system fault control method and device for a stability boundary, and belongs to the field of power systems, and the method comprises the steps: obtaining a current composite stability margin index of a power system in real time; when the index is greater than or equal to a preset threshold value, collecting a current operation scene sample set, and obtaining a current fault operation scene and an anticipated disturbance set in combination with the offline stable scene knowledge base; according to the fault operation scene and the anticipated disturbance set, adopting fast time domain simulation to obtain a dynamic response track, and performing power flow identification to obtain a power flow section and an influence node set; establishing a state space according to the composite stability margin index, the power flow section and the influence node set, training in a reinforcement learning environment in combination with a reward function, and outputting a fault control scheme; and performing fault control on the power system according to the scheme. Therefore, by implementing the method and the device, the problem that the accuracy of fault control is difficult to improve while the fault identification efficiency is difficult to guarantee in the prior art can be solved.

The application discloses a kind of commercial vehicle multifunctional double motor coupling active steering system and its control method, comprising: the angle of collection vehicle steering wheel, torque signal;According to the signal calculated, vehicle stability margin is calculated, and the state of electromagnetic actuator is determined;Limiting the transmission ratio required under working condition is calculated;The angle value required by auxiliary motor is calculated, and control signal is sent to auxiliary motor;The assist torque value required by main motor is calculated, and control signal is sent to main motor;The torque distribution value of auxiliary motor and main motor under ordinary working condition is calculated, and is sent to auxiliary motor and main motor respectively;Output corresponding torque or angle, complete vehicle steering.The application can improve the lightness of steering at low speed under ordinary working condition by double motor assist coupling;Under limiting working condition, main motor is assisted alone, and auxiliary motor is compensated to driver steering angle by double-row planetary gear module, can realize stepless variable transmission ratio, realizes active rollover control.

The application belongs to the technical field of engine control, and particularly relates to a deceleration control method and device for improving fan stability margin. The method comprises the following steps: S1, obtaining an engine deceleration start time, a low-pressure conversion speed after deceleration and a nozzle throat area; S2, discretizing a low-pressure conversion speed change interval into a plurality of low-pressure conversion speed control amounts; S3, superimposing a nozzle throat area increase amount on the basis of an initial value of the nozzle throat area to form a first nozzle throat area, and simultaneously determining a second nozzle throat area for maintaining stable operation of the fan; S4, selecting a minimum value from the two nozzle throat areas and a maximum value of the nozzle throat area to form a nozzle throat area adjustment amount corresponding to the low-pressure conversion speed control amount; and S5, adjusting the nozzle throat area according to the corresponding relationship between the low-pressure conversion speed control amount and the nozzle throat area adjustment amount. The application can ensure that the deceleration time meets the index requirement and improve the aircraft maneuvering performance.

The application belongs to the technical field of helicopter dynamics design, and discloses a kind of fast evaluation method of helicopter rotor body coupling stability frequency design, based on the change relation of rotor system characteristic frequency and body modal frequency with rotor speed, resonance center speed and speed stability margin are obtained, to carry out the fast evaluation of rotor body coupling stability, and according to the result of fast evaluation, whether the speed stability margin meets the design requirement is determined, to carry out the optimization design of rotor system characteristic frequency and body modal frequency, which can ensure that the rotor body coupling stability meets the design requirement in the early stage of design. The application avoids the problem of rotor body coupling stability, can carry out frequency design more accurately in each stage of type design, and has high universality and engineering application value.

Provided is a technique capable of maintaining a stability margin before adjustment of the gain filter of a motor control device even after adjustment. An adjustment support device 20 comprises: a frequency characteristic measurement unit 300 for measuring the frequency characteristics of a motor control device 1; a frequency characteristic acquisition unit 21 for acquiring frequency characteristics before adjustment from the frequency characteristic measurement unit 300; a stability margin reading unit 22 for reading a stability margin from the frequency characteristics acquired by the frequency characteristic acquisition unit 21; a stability margin setting unit 23 for setting the stability margin read by the stability margin reading unit 22 as a target margin for adjustment; and an adjustment unit 400 for adjusting a gain and a filter coefficient on the basis of the target margin.

The application discloses a kind of robust stability evaluation methods of phase-locked loop main leading isomeric multivariable converter power system, solve the problem of difficult robust stability analysis caused by isomeric converter phase-locked loop parameter coupling, parameter optimization has no reference.For: first, obtain system parameters, based on second-order phase-locked loop step-down model to construct uncertainty separation model;Then, combined with value set theory, whether the value set contains origin is judged to determine the robust stability of the system;Then calculate the multivariable stability margin K m , determine the dominant unstable oscillation frequency ω c ;Then analyze the moving trend of the value set of parameter change, determine the influence direction of parameter on system strength, introduce negative damping line under instability state to assist analysis;Finally, develop differentiated parameter optimization strategy, iterative optimization until the system meets the stability margin requirement.The application can quantitatively evaluate the robustness of the system, reveal the non-uniform parameter adjustment rule, provide accurate basis for parameter setting, effectively avoid small signal instability, and improve the robust stability of isomeric multivariable converter power system.

The present invention belongs to the field of trajectory control optimization, and specifically relates to an optimization method for a gliding missile controller based on an improved Gray Wolf algorithm. The method comprises the following steps: Step (1): Based on the dynamic characteristics analysis of the gliding missile, a disturbance motion equation of the missile body is established and simplified; Step (2): Based on the simplified disturbance motion equation of the missile body, under the conditions of zero interference and zero initialization, a suitable input control quantity and state vector are selected to construct its longitudinal state equation; Step (3): Based on the system state equation, an LQR linear quadratic regulator is constructed: the parameters of the weighting matrix Q matrix and the R matrix in the LQR linear quadratic regulator are optimized using the Gray Wolf algorithm with a nonlinear convergence factor to obtain the feedback gain matrix K, thereby improving the system response time and the stability of the new control system. The present invention optimizes the trajectory and improves the system response by selecting some parameters in the longitudinal disturbance equation as state variables and optimizing the feedback gain, thereby improving the stability margin of the system.

The application provides a wind turbine continuous low voltage ride through stability margin evaluation method, device, equipment and readable storage medium. When it is necessary to evaluate the continuous low voltage ride through phenomenon of the wind turbine in the wind and fire bundled delivery system, the method provided by the embodiment of the application can effectively explain and describe the mechanism of the continuous low voltage ride through phenomenon of the wind turbine in the high-power wind turbine and low-power synchronous unit scene of the wind and fire bundled delivery system, and determines the stability margin evaluation index of the wind turbine continuous low voltage ride through phenomenon. The stability margin quantitative evaluation of the wind turbine continuous low voltage ride through is completed by using the evaluation index, which is helpful to understand the fault cause and processing mode of the continuous low voltage ride through phenomenon of the wind turbine in the high-power wind turbine and low-power synchronous unit scene of the wind and fire bundled delivery system.

The invention relates to the technical field of transient stability analysis of a power system, in particular to a transient stability evaluation method and device for a wind turbine generator, and the method comprises the steps: constructing a full-order model of a control loop of a to-be-evaluated wind turbine generator, and carrying out the transient stability analysis of the full-order model of the control loop; and performing simulation aiming at different voltage sags, different phase-locked loop control parameters, different power grid line impedances and different grid-connected point d-axis current instructions of the to-be-evaluated wind turbine generator, and performing simulation verification on the transient stability of the to-be-evaluated wind turbine generator. According to the derived maximum estimation attraction domain and the property thereof, the transient stability quantitative evaluation index capable of intuitively reflecting the initial state of the transient process of the new energy unit and the boundary of the maximum estimation attraction domain is constructed, and the relationship between the evaluation index value and the state quantity change of the transient process of the unit is qualitatively and quantitatively analyzed; and the transient stability margin of the unit is quickly and visually reflected.

The invention discloses a gas turbine combustion stability online regulation and control method based on deep learning, and aims to solve the problem of combustion instability prevention and control under the scene that fuel components / heat values are variable and are constrained by emission. The method comprises the following steps: firstly, fusing unit load, fuel characteristics and dynamic pressure of a combustion chamber, and constructing a ten-dimensional fuel characteristic package and a 2,000-448-dimensional pressure sequence; then, through a self-adaptive stability margin estimation network containing a stability judgment trunk and a fuel condition calibration layer, in combination with comparison event online calibration, self-adaptive stability margin of cross-fuel alignment is output; matching the risk level with the threshold group, screening regulation and control actions in an emission qualified adjustable range, calculating the amplitude, and generating a regulation and control instruction draft; and finally, through closed-loop verification, outputting a final regulation and control instruction or a rollback instruction according to the stable response quantity. According to the method, online self-adaptive evaluation of the stability margin and closed-loop regulation and control under emission constraint are realized, the combustion instability risk is effectively inhibited, and the operation safety and continuity of the unit are improved.

The application discloses a kind of three-axis stable platform rotation inertia compensation method based on mechanics model, to platform body axis angle β zk , inner frame axis angle β yk , platform body to x p , y p , z p Axis of rotation inertia Inner frame to axis of rotation inertia Outer frame to axis of rotation inertia As the input information of decoupling link, the compensation value of rotation inertia is obtained by solving through mechanics model, is compensated to outer ring axis stabilization loop, compensates the servo control loop gain variation caused by the change of frame system rotation inertia.The application first gives the mechanics model between frame angular acceleration and total moment of force on frame axis, is used to compensate the gain of outer ring servo control loop when inner ring axis is large angle, guarantees the stable margin of servo control loop when platform frame system is at any position in inner ring.