133 results about "Equivalent control" patented technology

The invention discloses a coating machine unwinding tension control method which is characterized by comprising the steps that S1, parameters, operation data and tension data of a coating machine are collected, and a state-space equation of an unwinding tension control system is established; s2, constructing an obstacle function; s3, combining the obstacle function and constructing a non-singular sliding mode surface function; s4, solving an equivalent controller for controlling tension according to the non-singular sliding mode surface function; s5, optimizing key parameters of the equivalent controller by using an aurora optimization algorithm; s6, designing a self-adaptive control rate for improving the anti-interference capability of the unwinding tension control system; the adaptive control rate is combined with the equivalent controller, and a total control signal is output; s7, performing unwinding tension control on an unwinding tension control system according to the master control signal; according to the scheme, the speed of dynamic response can be adjusted, finite time convergence is enhanced, steady-state errors are eliminated, singularity is avoided, convergence is accelerated, and therefore high-precision control over an unwinding tension control system is achieved.

The invention relates to the technical field of industrial big data, in particular to a transformer consumption reduction intelligent control method and system based on a power generation end, and the method comprises the steps: building a source-load space-time correlated industrial big data set, determining an operation reference, and synchronously monitoring real-time electrical parameters; load component decoupling is executed, a basic load component is stripped, and a power fluctuation deviation parameter is extracted; reconstructing equivalent control power of a power generation end based on a nonlinear fluctuation compensation strategy; and constructing a power grid energy efficiency function to execute loss minimization optimization, determining a power supply voltage setting value and driving on-load voltage regulation. Through multi-dimensional data fusion and non-linear load reconstruction, the problem that a traditional method is difficult to deal with random fluctuation of the load is solved, collaborative optimization of transformer loss and line transmission loss is achieved, and operation energy consumption of a power supply loop of a power generation end is effectively reduced.

The invention discloses a permanent magnet synchronous motor control method of an adaptive fractional order fast terminal sliding mode. The method comprises the following steps: firstly, constructing a mathematical model of the permanent magnet synchronous motor in a d-q axis rotor rotating coordinate system; then designing a fractional order fast terminal sliding mode surface, and solving an equivalent control law of sliding mode control based on the designed fractional order fast terminal sliding mode surface; performing adaptive design on the switching control gain and the boundary layer thickness to obtain an adaptive switching control law; and integrating the equivalent control law and the adaptive switching control law to obtain a total control law. Compared with existing surface-mounted permanent magnet synchronous motor sliding mode control, the surface-mounted permanent magnet synchronous motor sliding mode control method introduces a fractional order fast terminal sliding mode surface on the basis of a traditional integral sliding mode so as to reduce system buffeting and ensure that tracking errors converge in finite time, and meanwhile designs a self-adaptive control law of switching control rate gain and boundary layer thickness. The uncertainty influence of external disturbance is counteracted, and the robustness of the system is improved.

The invention discloses a power grid multi-energy dynamic aggregation equivalence control method and system based on a knowledge graph, and relates to the technical field of power grid energy aggregation equivalence modeling, and the method comprises the following steps: obtaining power grid energy structure multi-source data, and constructing a power grid multi-class energy aggregation equivalence knowledge graph database; based on the electrical similarity between the knowledge graph database and the node residual voltage, quickly aggregating and dynamically regulating and controlling the multiple energy sources of the power grid, and constructing an aggregation equivalent model of the multiple energy sources of the power grid; performing power flow simulation on the aggregation equivalence model, obtaining evaluation data of the aggregation equivalence model, and controlling the structure and parameters of the aggregation equivalence model according to the evaluation data; according to the invention, flexible equivalence of the multiple types of energy sources of the power grid is carried out through a knowledge graph-based rapid real-time aggregation equivalence method considering the multiple types of energy sources of the power grid, so that the problem that centralized and distributed new energy sources and shearable load energy structures cannot be automatically and flexibly aggregated and equivalence to power grids of any voltage class rapidly and in real time is solved; and the method is not suitable for rapid real-time aggregation equivalence of multiple types of energy sources.

The invention relates to the technical field of power electronics, in particular to a predictive compensation quasi-sliding mode control method for a three-phase four-leg three-level inverter, and the method comprises the steps: building a continuous state space model; discretizing the continuous state space model, constructing a discrete state space model, defining an output error of the output voltage and a derivative of the output error, and defining a sliding mode function based on the output error of the output voltage and the derivative of the output error under the theory of introducing quasi sliding mode control; constructing a prediction model and predicting a sliding mode function value at a next moment, introducing an expansion model to extract a model error, and correcting a defined sliding mode function based on a deviation between a prediction value and the model error; constructing a repetitive controller to extract a periodic error component and generate a compensation signal; and fusing the compensation signal with an equivalent control quantity constructed based on the expansion model to form a final control input for the driving system. According to the method, buffeting can be suppressed to a great extent, the steady-state performance can be optimized, and fast dynamic response is taken into account while the robustness of the system is guaranteed.

The invention discloses a nonlinear flutter control method considering high-dynamic low-hysteresis and micro-motion characteristics of a proportional valve, and belongs to the field of proportional valve control. The method comprises the following steps: acquiring a detection signal of a controlled proportional valve in real time, and performing mean filtering processing on the real-time detection signal to filter a flutter part so as to obtain a basic detection signal; the controller obtains the valve front and valve back pressure difference, the target control signal current and the basic detection signal of the current proportional valve; the frequencies and the amplitudes of the driving control signal and the optimal flutter control signal are obtained; and the driving control signal and the flutter control signal finish addition operation in the controller to obtain an equivalent control signal, so that the control of the controlled proportional valve is realized. The method is applied to a closed loop feedback link, and hysteresis can be greatly reduced. Under the control method, the valve element is always in a macroscopic stable and microcosmic jittering state, so that the speed of responding to a control signal is higher, the dead zone and saturation zone range of a proportional valve current-displacement curve can be reduced, and the linearity is higher.

The invention belongs to the technical field of artificial intelligence, and discloses an actuator fault performance compensation method for a wind power plant grid-connected interconnection system, and the method comprises the steps: building a dynamic model of a nonlinear interconnection system containing a wind power plant; then, in combination with an actuator fault, constructing a state-space equation of a nonlinear system introducing a neural network; a composite observer with a dynamic event triggering mechanism is constructed, and estimation of the system state, external interference and actuator faults is achieved; according to the output of the composite observer, constructing a sliding mode safety compensation controller for realizing disturbance and fault compensation, and further obtaining an equivalent controller and a switching controller; and constructing a system master controller according to the equivalent controller and the switching controller. According to the invention, comprehensive estimation of the system state, external disturbance and actuator faults can be realized, active compensation of disturbance and faults can also be realized, and the system control stability is improved.

The invention relates to the technical field of permanent magnet synchronous motors, and particularly discloses a permanent magnet synchronous motor low-buffeting terminal sliding mode control method based on adaptive disturbance compensation, comprising the following steps: S01, redefining a motor rotational inertia mathematical model; s02, improving a traditional nonsingular fast terminal sliding mode surface based on nonlinear system representation, and constructing a novel dynamic gain nonsingular fast terminal sliding mode surface; s03, performing derivation on the novel dynamic gain nonsingular fast terminal sliding mode surface, and combining a derivation function with nonlinear system representation to obtain an equivalent control law ieq; and S04, adopting an exponential reaching law isw as a switching control law of the sliding mode controller, and obtaining a novel different fast terminal sliding mode controller model according to an equivalent control principle in combination with the equivalent control law ieq and the exponential reaching law isw. The invention aims to improve the tracking response speed of a position instruction during servo control of the permanent magnet synchronous motor.

The invention discloses a wind power plant equivalent frequency response modeling method considering working condition uncertainty and an equivalence method, belongs to the technical field of power system modeling and equivalence, and aims to solve the problem that no method capable of considering the working condition uncertainty of units in a wind power plant to perform equivalent aggregation on the frequency response of the whole wind power plant exists at present. According to the method, modeling is carried out on the wind speed distribution uncertainty in a wind power plant by adopting a probability method, a wind power plant wind speed distribution scene is generated based on a three-parameter Weibull distribution function, and the working condition uncertainty of each unit is represented; dividing the wind power plant into a non-frequency modulation area, a comprehensive inertia and overspeed load shedding control area and a comprehensive inertia and variable pitch control area according to the wind speed distribution and the corresponding wind speed during fan output; and based on a partitioning result, determining an equivalent influence coefficient and an equivalent control coefficient by utilizing parameters of each wind turbine generator, obtaining a wind power plant equivalent frequency response model considering working condition uncertainty by combining a wind turbine generator frequency response model, and realizing equivalence based on the model.

The invention provides a cooling tower system optimal operation parameter self-adaptive regulation and control method, which comprises the steps of collecting multi-source high-frequency data in a system operation process, and obtaining a standardized variable sequence through normalization, abnormal value processing and time sequence consistency verification. A sliding window mechanism and a lightweight causal discovery algorithm are combined, a causal atlas is dynamically constructed and fused, parameters are corrected in real time through an incremental Bayesian network, a dominant causal path is extracted, lightweight CMA-ES rolling optimization is executed in an equivalent control subspace after dimension reduction, optimal control parameters are solved, system closed-loop adjustment is driven, and the optimal control parameters are obtained. Meanwhile, a map confidence degree evaluation and depth reconstruction mechanism is set, dynamic self-adaption of a causal structure and parameters is ensured, the response capacity of a cooling tower system to working condition changes can be improved, and energy efficiency and operation stability are optimized.

The invention provides a CPS adaptive sliding mode control method and device under FDI attack and actuator fault, and the method comprises the following steps: constructing an information physical system model under FDI attack and actuator fault, introducing a dynamic event triggering communication mechanism into a measurement channel, and considering the system time delay from a sensor to an actuator; constructing a state-fault estimator according to the information physical system model; establishing a discrete sliding mode function according to the established state-fault estimator; based on the discrete sliding mode function, a system equivalent control law and a system sliding mode dynamic state are obtained; constructing an augmented closed-loop system according to the dynamic state of the sliding mode of the system; and constructing a self-adaptive sliding mode controller based on the system equivalent control law, and performing compensation control on the augmented closed-loop system by adopting the self-adaptive sliding mode controller. According to the method, adaptive factors can be adjusted according to different attack occurrence frequencies so as to optimize control performance, and system uncertainty such as FDI attacks and system actuator faults can be effectively handled.

The invention discloses a mechanical arm trajectory tracking method and system based on interference estimation compensation, and belongs to the technical field of trajectory tracking. The method comprises the steps that expected trajectory information of a mechanical arm is obtained, the expected trajectory information comprises the expected position qd, the expected angular speed # imgabs0 # and the expected angular acceleration # imgabs1 #, and a mechanical arm dynamic model is established based on the given system total disturbance d; designing a neural network interference observer, estimating the total disturbance of the system, and obtaining a system interference estimated value y; designing a super-spiral sliding mode controller and a global nonsingular terminal sliding mode surface s, and obtaining an equivalent control moment ueq based on expected trajectory information of the mechanical arm and total disturbance d of a given system; and based on the system interference estimated value y and the equivalent control moment ueq, a mechanical arm control law u meeting Lyapunov stability analysis is obtained, and mechanical arm trajectory tracking is achieved. The stability and trajectory tracking performance of the mechanical arm system can be improved.

The invention discloses a grid-connected distributed photovoltaic inverter control method and system. The method comprises the following steps: selecting a first control object, and establishing a first controller based on the first control object; establishing a first equivalent control signal, and updating the first controller based on the first equivalent control signal to obtain a second controller; and controlling the grid-connected distributed photovoltaic inverter according to the second controller. Through the control method, the power grid operation state change when the voltage of the power grid drops can be effectively handled, and the stability and reliability of the grid-connected distributed photovoltaic inverter are improved. When the voltage of the power grid drops, the voltage of the direct current link capacitor is kept constant, so that the voltage of the direct current link can be prevented from exceeding the voltage limit of the capacitor, and the off-network phenomenon caused by triggering the protection device is avoided.

The invention discloses a large dynamic pressure aerodynamic force / aerodynamic heat / structure / control multi-field coupling calculation and control method. The method comprises the following steps: calculating to obtain aerodynamic force / aerodynamic heat / structure multi-field coupling characteristics of a large dynamic pressure aircraft; aerodynamic model correction is carried out according to multi-field coupling characteristics, and a rigid-elastic coupling dynamic model of the large dynamic pressure aircraft is established; designing a sliding mode surface capable of ensuring the stability of a rigid-elastic coupling mode, and obtaining an equivalent control item based on a rigid-elastic coupling dynamic model; adding a super-spiral sliding mode switching control item to form a super-spiral sliding mode closed-loop control law; and designing an output layer weight adaptive law of the BRF neural network state observer, realizing online estimation of a rigid-elastic coupling mode, and forming a super-spiral sliding mode closed-loop control law based on intelligent online estimation of the rigid-elastic coupling mode for a high dynamic pressure flight environment. According to the method, the aerodynamic / thermal / structural multi-field coupling characteristics of the aircraft in the large dynamic pressure environment can be accurately obtained, and finally the purpose of high-precision and high-robustness control in the large dynamic pressure flight environment is achieved.

The invention provides a Markov jump-based mechanical arm preset time trajectory tracking control method, which comprises the following steps of: calculating a trajectory tracking error by establishing a two-degree-of-freedom mechanical arm dynamic model with a Markov jump characteristic; a trajectory tracking error is subjected to nonlinear transformation, a nonsingular terminal sliding mode surface is constructed in combination with a preset convergence time upper limit function, and then a control torque is synthesized through an equivalent control item and a robust switching item containing a sliding mode surface sign function and a switching gain to drive a mechanical arm. And the trajectory tracking error is difficult to converge in the preset time.

The invention relates to a trajectory control method based on a time-varying fuzzy sliding mode, and the method comprises the steps: building a system dynamic model, designing a high-order observer, estimating the position, speed, acceleration and lumped disturbance in real time, and avoiding the conservative property of a fixed gain through adaptive gain adjustment; constructing a fuzzy sliding mode control law, combining an equivalent control item and a switching control item, and dynamically adjusting an error weight by using a fuzzy logic system; and designing a dynamic amplitude limiter and a delay compensation mechanism, smoothly limiting the control instruction to the physical limit of the actuator, and feeding back the correction control instruction based on the observer to offset the delay influence. According to the invention, through time-varying fuzzy sliding mode control, adaptive observer gain and anti-saturation compensation, trajectory tracking precision and system robustness are effectively improved.

The invention also discloses an SIDO Boost converter terminal complementary superspiral sliding mode improved active-disturbance-rejection control method. The method specifically comprises the following steps: step 1, establishing a state space averaging model by using a state space averaging method; 2, fitting the state space average model into a standard second-order system normal form; 3, designing a fractional order cascade expansion state observer according to a standard second-order system normal form; step 4, applying the observation value obtained in the step 3 to a terminal complementary sliding mode controller; 5, introducing the super-spiral sliding mode reaching law into the terminal complementary sliding mode; step 6, according to the equivalent control law and the switching control law, obtaining a total control law of the system after summation; and step 7, applying the observer and the controller to a main voltage single closed loop and a branch voltage outer loop and a current inner loop. The problems that a traditional active-disturbance-rejection control method is insufficient in external total disturbance estimation precision of the single-inductor dual-output converter and cross influence exists between two output branches are solved.

The invention relates to the technical field of new energy power generation, in particular to a doubly-fed fan VSC-HVDC (Voltage Source Converter-High Voltage Direct Current) subsynchronous oscillation robust integral predefined time sliding mode control method, which comprises the following steps: S1, establishing a grid-side converter model in a doubly-fed fan; s2, establishing a phase-locked loop model in the doubly-fed fan; s3, constructing an integral sliding mode surface, and obtaining dynamic characteristics and equivalent control input of a sliding mode system; s4, designing approaching control input, and obtaining an integral predetermined time sliding mode control law; and S5, implementing an integral predetermined time sliding mode control law. Compared with a traditional PI control strategy, the robust integral predefined time sliding mode control method for the subsynchronous oscillation of the double-fed fan VSC-HVDC, provided by the invention, has the advantages that the oscillation can be converged in a shorter time, and the robustness is higher.

Disclosed in the present application are a phase shift angle control method, a non-singular sliding mode controller, and a wireless power transmission system. The method comprises: on the basis of a non-singular sliding mode surface equation, a state-space average equation and circuit data, obtaining an equivalent control rate; on the basis of the non-singular sliding mode surface equation and the circuit data, obtaining a sliding mode surface; on the basis of the sliding mode surface, obtaining a switching control rate; on the basis of the equivalent control rate and the switching control rate, obtaining a total control rate; and on the basis of the total control rate, adjusting a phase shift angle between driving signals of switching tubes of a wireless power transmission system. In the present application, non-singular sliding mode control of a wireless power transmission system is realized, the non-singular sliding mode control is combined with the principle of chattering elimination for a sliding mode, and a mathematical model of a control system is reconstructed while the order of the system is not increased, such that variables of actual control and measurement are reduced, thereby reducing the system complexity, and the chattering of the system is inhibited while the response speed and the steady state of the system are improved and steady-state errors are reduced, thereby improving the response speed and the anti-interference capability.

The invention discloses a cascade control method for a smoke concentration emission value of a coal-fired unit. The method comprises the following steps: establishing a dust removal dynamic characteristic model of a dry electric dust remover and a wet desulfurization tower based on a step test; a cascade control framework is constructed, an inner loop controller directly controls the dry-type electric precipitator, and an outer loop controller generates an inner loop set value according to the deviation between system output and the set value; an inner loop controller and an outer loop controller are set at the same time through a compensation method, on the basis of considering dynamic coupling of the inner loop and the outer loop, parameters of the outer loop controller are designed, the dynamic characteristics of an equivalent controlled object are improved, and then parameters of the inner loop controller are designed according to the dynamic characteristics of the equivalent controlled object; the controller is developed, and the control method is applied in the actual industrial process. According to the method, on the basis that the auxiliary dust removal capacity of the desulfurization tower is fully utilized, dynamic dust removal control over the dry-type electric dust remover is achieved.

The present invention relates to a trajectory control method based on time-varying fuzzy sliding mode. The method includes: establishing a system dynamics model, designing a high-order observer to estimate the position, velocity, acceleration and lumped disturbance in real time, and avoiding the conservatism of fixed gains through adaptive gain adjustment; constructing a fuzzy sliding mode control law, combining the equivalent control term and the switching control term, and dynamically adjusting the error weight by using a fuzzy logic system; designing a dynamic limiter and a delay compensation mechanism to smoothly limit the control command to the physical limit of the actuator, and at the same time correcting the control command based on the observer feedback to offset the delay effect. The present invention effectively improves the trajectory tracking accuracy and system robustness through time-varying fuzzy sliding mode control, adaptive observer gain and anti-saturation compensation.

A sliding mode control method for a permanent magnet synchronous fan based on an exponential control law belongs to the field of sliding mode control for fans and is used for speed loop control of a permanent magnet synchronous generator to achieve stable tracking of the optimal speed of the fan. The scheme constructs a terminal sliding mode function based on exponential convergence and designs a controller to effectively deal with the nonlinear characteristics of the system, and can have the characteristics of high-precision tracking of reference signals and suppression of jitter while converging quickly. By avoiding the differential processing of the exponential function in the equivalent control, the singularity problem of the conventional terminal sliding mode is avoided. The invention has the characteristics of simple structure, high control accuracy, fast convergence speed, small jitter and strong anti-interference ability.

This invention discloses an improved integrated winding structure for a bearingless electrically excited doubly salient pole motor, relating to the field of bearingless motor technology. It integrates the levitation winding and excitation winding of a traditional bearingless electrically excited doubly salient pole motor into an integrated levitation winding. A control method is provided to enable the integrated winding configuration of the bearingless electrically excited doubly salient pole motor for power generation and stable levitation. This control method includes a displacement control module, a levitation current calculation module, and a levitation current control module. Stable rotor levitation can be achieved by controlling the levitation winding current. This scheme optimizes the winding arrangement and achieves mutual scheduling of power generation and levitation capabilities through equivalent control. Compared to traditional bearingless doubly salient pole motors, the integrated winding configuration bearingless electrically excited doubly salient pole motor designed in this invention improves the utilization rate of slot space, expands the working range of the bearingless doubly salient pole motor, and its overall operating state is more flexible.

The application discloses a transient overvoltage suppression method and system, relates to the field of overvoltage protection of a power system, and comprises the following steps: constructing a state space expression of a high-voltage direct-current power transmission system; inputting a direct-current current and a receiving-end direct-current voltage into the state space expression to determine an equivalent control quantity; determining a tracking error determined according to the direct-current current and a reference current as a sliding mode quantity; determining a switching control quantity based on a second-order sliding mode super-helix algorithm; determining a super-helix sliding mode constant current control rate according to the equivalent control quantity and the switching control quantity; the super-helix sliding mode constant current control rate meets a constraint condition of Lyapunov stability; substituting the sliding mode quantity into the super-helix sliding mode constant current control rate to determine a rectifier side trigger angle signal; and the rectifier side trigger angle signal is used for inputting a rectifier station to suppress transient overvoltage of a sending-end alternating-current system. The application is easy to implement suppression of the sending-end transient overvoltage, is convenient and simple, and can improve dynamic performance and steady-state performance of the high-voltage direct-current power transmission system.

This invention provides a control method for a lower limb exoskeleton rehabilitation robot based on the sliding mode optimization method, belonging to the field of medical rehabilitation robot control technology. The method includes: establishing a two-degree-of-freedom dynamic model of the lower limb exoskeleton rehabilitation robot, and transforming it into a linear state-space model using feedback linearization technology; designing a linear quadratic regulator (LQR) for the linearized model to obtain the optimal feedback gain matrix; constructing an integral sliding surface containing the optimal feedback gain matrix, so that the equivalent control law of the system in the sliding mode possesses the globally optimal dynamic performance of the LQR; and based on adaptive preset time theory, constructing a sliding mode reaching law and an adaptive gain update law containing novel nonlinear functions to generate the final control torque.

The present invention discloses a method and device for model predictive control of rectifier harmonic suppression based on current variance. This method realizes the indirect control of current harmonics by controlling the current variance. Through offline experiments, the relationship between the load current and the current variance under different current harmonics is measured, and the functional relationship between the two is obtained by curve fitting, avoiding the harmonic calculation link and reducing the computational load. This method can achieve the equivalent control of current harmonics with a relatively small computational load. In addition, in model predictive control, through hierarchical control, the computational complexity is reduced, the design of weight coefficients is avoided, and the balanced control of the neutral point voltage is achieved. By setting a satisfaction interval, the control target is limited within a certain fluctuation range, enabling the control strategy to obtain a higher control freedom and achieving the global optimum of the control effect.

The invention provides a water pressing plate self-calibration fault-tolerant control method and system and a computer readable medium, and relates to the technical field of ship stabilization. The self-calibration fault-tolerant control method for the water pressing plate comprises the following steps: S1, acquiring attitude data of a ship and state data of each actuator; s2, calculating according to the attitude data to obtain a current expected control torque vector, and calculating according to the state data to obtain a current equivalent control efficiency matrix; s3, calculating the current health degree of each actuator according to each piece of state data; s4, according to the current expected control torque vector, the current equivalent control efficiency matrix and each current health degree, current control input data of each actuator is obtained through calculation, and the actuator is suitable for driving the corresponding water pressing plate assembly according to the corresponding current control input data; and S5, the steps from S1 to S4 are repeatedly executed till the ship is in the expected pose.

The invention relates to the technical field of stirring, and provides a stirring device which comprises a barrel body, a cover body, a stirring mechanism and a scraping mechanism. The cover body is arranged on the barrel body; the stirring mechanism is provided with a driving part and a plurality of stirring parts, the driving part is arranged on the barrel body, and the stirring parts are arranged in the barrel body and connected with the driving part; the scraping mechanism is arranged in the barrel body and used for scraping the dipping tool. According to the stirring device provided by the invention, the cover body is arranged on the barrel body, and in the processes of stirring and dipping a lubricant, the cover body is not detached, so that the requirement of subsequent sealed storage of the lubricant is ensured; the stirring mechanism drives a plurality of stirring parts to stir simultaneously through one driving part, fluid vortex can be generated, lubricant mixing is promoted, and therefore the lubricant stirring effect is improved; when the dipping tool dips the lubricant from the barrel body and is taken out for use, the dipping tool is scraped by the scraping mechanism, so that the requirement on equivalent control of dipping the lubricant by the dipping tool every time is met, and the standardized operation of smearing the lubricant is realized.

The invention discloses a permanent magnet synchronous motor sensorless control method based on a sliding-mode observer, and the method comprises the steps: collecting the three-phase current and three-phase voltage of a permanent magnet synchronous motor, and converting the three-phase current and three-phase voltage into a two-phase current component and a two-phase voltage component under a static coordinate system; inputting two-phase current and voltage components into a novel sliding mode observer; according to the novel sliding-mode observer, a sinusoidal saturation switching function is adopted to replace a sign function, and a variable gain function based on cooperative control of a speed error and a state variable is adopted; taking the product of the sine type saturation switching function and the variable gain function as an equivalent control quantity to obtain a back electromotive force estimated value; inputting the back electromotive force estimated value into a phase-locked loop structure, and extracting a rotor estimated electrical angular velocity and a rotor estimated position angle through the phase-locked loop structure; and realizing sensorless vector control of the permanent magnet synchronous motor by using the estimated electrical angular velocity and the estimated position angle of the rotor. According to the method, the problem of phase lag is solved, and effective suppression of rotating speed buffeting is realized.

The application discloses a communication-restricted multi-agent tracking control method for trains, which comprises the following steps: S1, for a high-speed train dynamics model, a train formation dynamics model is designed; S2, a non-singular sliding mode surface is designed, which is brought into a dynamics equation, an equivalent control law and a total control law are designed; S3, a fixed threshold strategy is designed based on a control input signal error, and an event trigger condition is constructed; S4, through information interaction of adjacent vehicles, unmeasured states are estimated by using local measurable states, full-state feedback is provided for a controller, and a distributed observer is designed; the application has the beneficial effects that an improved terminal sliding mode surface is designed by using a non-singular terminal sliding mode surface, wherein the non-singular terminal sliding mode surface is a coprime odd number, fraction exponent irreducibility is ensured, periodic oscillation is avoided, and the singularity problem of traditional sliding mode control in time is eliminated by the fraction exponent term.