10 results about "Equilibrium point" patented technology

This invention relates to a method for calculating and evaluating the stability domain boundary of a new energy power system, addressing the problem of significant conservatism in evaluating the transient synchronization stability of grid-connected and grid-connected converters in current new energy power systems. The method includes: calculating the equilibrium point of the target nonlinear system and determining the local stable manifold of the stable equilibrium point; plotting the global stable manifold of the target nonlinear system using manifold theory and accurately observing the dynamic behavior of the target nonlinear system in the global state space; further extending the proposed transient stability domain boundary calculation method to a high-dimensional phase space; and quantitatively evaluating the transient stability margin of the target nonlinear system under different faults using the Monte Carlo method. The calculation method of this invention accurately characterizes the stability domain boundary of the target nonlinear system, providing important reference value for evaluating the transient synchronization stability of new energy power systems.

The application discloses a power system output differential passivity measurement method based on input-state trajectory, which comprises the following steps: S1, input state trajectory data is acquired; S2, data normalization processing is performed; S3, a linear matrix inequality constraint is constructed; based on the normalized matrix in S2, the definition of output differential passivity is extended to the form of a matrix inequality constraint; and S4, an optimal output differential passivity index is solved. The power system output differential passivity measurement method based on input-state trajectory can further check the output differential passivity of the power system and calculate an optimal output differential passivity index under the condition that the internal parameters of equipment are not dependent, the equilibrium point is not known in advance and measurement noise exists, by means of the measured input state trajectory.

The present application relates to the technical field of network security, in particular to a network attack and defense strategy selection method and system based on three-party evolutionary game, a three-party evolutionary game model is constructed by an attacker, a defender and a user as network attack and defense confrontation participants based on evolutionary game theory, the participants of the three-party evolutionary game model imitate the advantageous strategy in the evolutionary game and adjust their own strategy selection under the driving of game income; the stability of the three-party evolutionary game model is solved by using a three-party behavior strategy selection dynamic equation, the equilibrium point of the three-party evolutionary game model is obtained, and the best selection strategy of each subject of the participants is obtained according to the equilibrium point of the three-party evolutionary game model. The present application models and describes the real attack and defense scene more accurately by constructing a game model with the participation of the attacker, the defender and the user, and provides technical support for solving the network information security problem.

The application discloses a kind of based on KAN network and adaptive unified trajectory optimization explainable identification method and equipment, belong to artificial intelligence technical field.The method includes: using the adaptive unified trajectory optimization method of combining adaptive first-order and second-order moment and gradient amplification mechanism to carry out parameter optimization to improved Kolmogorov-Arnold deep neural network;Optimization, pseudo-transient continuation and quotient gradient system modify traditional gradient flow by a specific way, so as to amplify smaller gradient, and accelerate the trajectory away from flat area or saddle point area, so as to improve the stability of training and reduce the possibility of falling into local minimum;The method of introducing pseudo-time continuation is used to quickly determine the steady-state solution of differential equation during network training;Adaptive updating technology is used to update pseudo-time step.The application converts KAN training problem into finding stable equilibrium point by constructing quotient gradient system, and realizes fast and robust convergence.

This invention discloses a transient stability analysis method and system for a multi-machine grid-connected system. First, a transient model of the system is established, and the stable equilibrium point before the fault is determined based on the power balance equation and the eigenvalues ​​of the Jacobian matrix. Using the stable equilibrium point as initial values, the fault trajectory is calculated, and an interpolation correction algorithm is introduced to eliminate discrete simulation step size errors and accurately locate the point on the fault trajectory where the potential energy derivative changes from positive to negative. Using this point as an initial value, the system iteratively searches for the minimum point of power imbalance along the gradient descent path. Solving the power balance equation using the minimum point as an initial value yields the dominant unstable equilibrium point. Finally, the energy of the dominant unstable equilibrium point is used as the critical energy to determine whether the system is stable after the fault is cleared. The method provided by this invention reduces the conservatism of the traditional energy function method for stability assessment in multi-machine systems, effectively reduces the multi-saddle point interference problem in multi-machine systems, and accurately locates the dominant unstable equilibrium point related to the fault path.

This application belongs to the field of robot motion control technology and discloses a robot trajectory tracking method, device, storage medium, and electronic device. First, the robot system is dynamically modeled; the current error state vector is calculated, and the dynamic equation of the error state is constructed; the error state is transformed into a three-dimensional z-space, and the dynamic equation of the error state is constructed in the three-dimensional z-space; a sliding mode surface is constructed in the three-dimensional z-space, and the equivalent phase space constraints corresponding to the sliding mode surface are calculated based on the optimization objective and constraints; a subspace is constructed according to the control strategy, and the subspace where the current state is located is determined through a search algorithm; the relative distances of the current state to all subspaces are calculated, and the optimal sliding mode surface is determined based on the relative distances; the relative relationship between the optimal sliding mode surface and the current error is calculated, and the relative relationship is input into the control law to determine the final control quantity. This method can significantly suppress robot jitter when approaching the equilibrium point, while improving computational efficiency and achieving optimal arrival at the target control point.

The application discloses a converter control method and device considering AC side phase angle feedback and a storage medium, and belongs to the field of novel power grid formation control. The method comprises the following steps: for a DC-AC power converter, considering the connection of the DC-AC power converter with an infinite bus or a dynamic center inertia (COI) power grid, a converter model containing explicit expressions of energy dynamics, DC links, LC output filters, transmission lines and the like is established, and a closed-loop dynamic equation under a hybrid angle control (HAC) strategy is determined; based on the model and the control strategy, the existence, stability and boundedness of equilibrium points of a closed-loop system are analyzed, and corresponding parameter conditions are given; considering the safety constraints of the power converter, a current limiting control compatible with the hybrid angle control (HAC) is designed, and the stability thereof is analyzed; the implementation method of the hybrid angle control (HAC) in actual application is researched and designed, the robustness thereof is analyzed, behaviors of the hybrid angle control (HAC) under different working conditions are analyzed, and numerical examples are used for verification.

The present invention relates to an energy-function-based transient synchronization stability evaluation method for a grid-connected system including multiple virtual synchronous generators, the method comprising the following steps: constructing a system non-linear reduced-order mathematical model suitable for transient synchronization stability analysis; taking into consideration dynamic strong coupling of active power control and reactive power control and dynamic interaction of multiple virtual synchronous generators, analyzing and constructing an energy function of the system; by means of the closest unstable equilibrium point method and an optimization method, respectively calculating a maximum energy value for ensuring system stability and a maximum energy value for ensuring that the system does not trigger current amplitude limiting under the condition that the system does not trigger current amplitude limiting after fault removal; taking the smaller value of the two to obtain a critical energy value for ensuring transient stability of the system; calculating a trajectory of the system during the fault by means of numerical integration to obtain the state of the system at the moment of fault removal; substituting the state of the system at the moment of fault removal into the energy function to calculate an energy function value of the system at the moment of fault removal; and evaluating transient synchronization stability of the system.

This invention belongs to the field of sliding diaphragm position tracking control technology, specifically relating to a preset-time anti-interference sliding diaphragm position tracking control method and system for a PMSM (Motor Particulate Module). It includes constructing a mathematical model for position tracking control of the disturbed PMSM, using the q-axis stator current as the control input for motor position tracking control, constructing an error dynamics expression based on observed position error and observed velocity error, and introducing a time-varying scaling function based on arbitrary duration. A switching time point is set within the arbitrary duration, a continuously differentiable and bounded time-varying scaling function is introduced, and then, through coordinate transformation, an interference observer is constructed, a preset-time controller is designed, and finally, the control input is obtained, enabling the mechanical angular displacement to track the desired mechanical angular displacement within a specified time range. Using the scheme of this invention, the boundedness of all closed-loop signals is guaranteed, and both the motor angular displacement error and angular velocity error converge to the equilibrium point within a preset time.