57 results about "Stability margin" patented technology

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.

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 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.

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 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.

This invention discloses a stability assessment and control method for grid-connected converters during fault recovery based on the hybrid potential function theory. First, the grid-connected system parameters of the grid-connected converter are obtained, and its equivalent model in a synchronous rotating coordinate system is established. Second, the hybrid potential function of the system is constructed to extract the current potential and voltage potential. Then, an analytical stability criterion is derived as an evaluation index for quantifying the transient stability of the system. Finally, the peak value of transient overvoltage is substituted into the evaluation index to assess the system stability. Based on the evaluation index, the system parameters during fault recovery are adjusted to improve the system's stability margin, suppress voltage divergence and power oscillation at the moment of fault clearing, and ensure the converter's continuous synchronous support capability. This invention reveals the mechanism of transient overvoltage leading to the contraction of the system's stable domain at an analytical level, which can avoid the instability risk caused by overvoltage and provide a reliable quantitative basis for the safe operation of grid-connected converters.

The invention relates to the field of fluid machinery, and discloses a turbine compressor supported by vector magnetic control magneto-rheological bearings and a control method, the turbine compressor comprises an impeller, a rotating shaft and the vector magnetic control magneto-rheological bearings arranged at the two ends of the rotating shaft; an impeller is fixedly arranged on the rotating shaft, the impeller and the rotating shaft form a rotor, and the rotor is used for compressing and conveying gas; the vector magnetic control magneto-rheological bearings are installed in the compressor shell and arranged at the two ends of the rotating shaft to provide radial supporting for the rotor, and then the rotor is supported on the shell. The turbine compressor has the functions of non-contact start-stop protection and active stability enhancement, the reliability and stability margin of the turbine compressor are remarkably improved, and the turbine compressor is particularly suitable for high-load and long-period operation working conditions.

This invention discloses an intelligent collaborative control method and system for industrial equipment based on the Internet, belonging to the technical field of intelligent control. The method includes the following steps: Step S1, determining whether the control time deviation of the equipment is fixed; Step S2, setting a first cooling priority, setting open-loop control parameters for the valve opening time, and controlling the equipment according to the open-loop control parameters; Step S3, setting closed-loop control parameters for the valve opening time, and compensating the equipment according to the closed-loop control parameters. This invention adopts an open-loop control mode, pre-calculating the duty cycle sequence based on a feedforward compensation mechanism, improving the system's response speed and reducing the real-time calculation burden. When the control time deviation is not fixed, a control mode combining open-loop and closed-loop control is adopted, enhancing the system's robustness to parameter drift and external disturbances. The Nyquist stability criterion is introduced to verify the closed-loop control parameters online, achieving a balanced optimization of control performance and stability margin.

The invention discloses a stage matching method and device for the overall pneumatic stability margin of a gas compressor, and the method achieves the single variable control and the quantitative evaluation of the stability margin through independently analyzing the influence of the matching of each stage in a multi-stage gas compressor on the overall pneumatic stability margin under the condition of not changing the influence of the B parameters of a system. And a reliable stage matching optimization basis is provided for the design of the gas compressor, so that the reasonable design and adjustment of the stage matching relationship of the gas compressor are realized.

The invention belongs to the technical field of power system stability control, and particularly discloses an optimization method for ultralow frequency oscillation damping characteristics of a one-pipe double-machine type pumped storage power station. The method comprises the following steps: firstly, constructing a kinetic model of the one-pipe double-machine pumped storage power station; analyzing the stability of the model by using Hopf bifurcation, and determining critical parameters and dividing a stability domain through a Jacobian matrix eigenvalue; introducing a stability margin to quantify the stability, and analyzing a first influence of different working condition points on the oscillation frequency and the damping ratio under the same stability margin; obtaining a second influence of the parameter on the oscillation frequency and the damping ratio through sensitivity analysis; and constructing a three-dimensional curved surface of the oscillation frequency, the damping ratio and the control parameters based on the two influences, dividing an equal-frequency area and an equal-damping-ratio area on the three-dimensional curved surface under the stable allowance working condition, and identifying the optimal control parameters from the equal-frequency area and the equal-damping-ratio area. Optimized identification of the key parameters is realized, and support and guidance are provided for suppressing ultra-low frequency oscillation of the pumped storage power station and improving safe and stable operation of the system.

This invention discloses a stability margin testing method for a distributed fly-by-wire flight control system, relating to the field of flight control system testing technology. The stability margin testing system for this distributed fly-by-wire flight control system includes a flight control computer, actuator control electronics, actuator servo controllers, actuators, control surfaces, a digital-to-analog converter module, and a frequency response analyzer. The stability margin testing method for this distributed fly-by-wire flight control system achieves the conversion and output of digital and analog signals by adding or retrieving digital-to-analog converter modules and analog-to-digital converter modules. It also acquires flight control commands and excitation signals from the frequency response analyzer, modifies the calculation logic of the actuator servo controller to superimpose the excitation signals and flight control commands, transmits the superimposed commands to the actuators, and simultaneously returns them to the digital-to-analog converter module. The digital-to-analog converter module converts the digital signals into analog signals and transmits them to the frequency response analyzer to calculate the stability margin.

The invention provides a gas compressor control method, device and equipment based on guide and static blade joint blending and deflation coupling, and can be applied to the technical field of aero-engines and gas turbine gas compressors. The method comprises the steps that according to the intersection point of a characteristic curve of the gas compressor at the preset rotating speed and a common working line of the gas compressor, the working point of the gas compressor at the preset rotating speed is determined, and the common working line is a steady-state working condition point track determined according to the whole engine matching relation; according to the difference between the blade geometric inlet angle and the inlet relative airflow angle of the pitch diameter section of the rotor blade of the gas compressor, the attack angle of the pitch diameter section of the rotor blade of the gas compressor corresponding to the working point is determined; and under the condition that it is determined that the attack angle does not meet the preset angle range, the adjusted attack angle meets the preset angle range and the stability margin at the preset rotating speed is larger than or equal to the preset margin by adjusting the installation angle of an adjustable guide vane and an adjustable static vane of the gas compressor and adjusting the gas bleeding amount.