202 results about "Low-frequency oscillation" patented technology

The invention belongs to the technical field of matching control of a network construction type system, and particularly discloses a power feedback control method suitable for matching control low-frequency oscillation suppression, which comprises the following steps: establishing a power-frequency transfer relation of a multi-matching control parallel system, analyzing the torque of the multi-matching control parallel system based on a damping torque method, and calculating the power-frequency transfer relation of the multi-matching control parallel system; determining an introduction factor of a negative damping torque component in the multi-matching control parallel system and a stability condition in the multi-matching control parallel system; and then additional damping control based on power feedback is designed through a lead-lag compensator, a negative damping torque part in the multi-matching control parallel system is compensated, and power feedback control is completed. According to the method, the problems that the dynamic response of the whole system becomes extremely complex due to the dynamic interaction among the converters when a plurality of matched control network-forming converters exist in the network-forming system, and the oscillation suppression effect under the multi-machine system is difficult to guarantee by the existing suppression strategy are solved.

The invention provides a generator set active power low-frequency oscillation online identification method and system, and relates to the field of operation safety of generator sets, and the method comprises the steps: obtaining active power data of a generator set, and carrying out the preprocessing of the active power data; setting a sliding window, scanning the preprocessed active power data through the sliding window, performing Prony decomposition on the data in the window, and obtaining a plurality of cosine components in each window; judging whether the window is a low-frequency oscillation suspected window or not according to a preset frequency threshold value, and calculating the maximum amplitude in all cosine components of the low-frequency oscillation suspected window; according to a preset continuity threshold value and an amplitude threshold value, the maximum amplitude mean value of the continuous low-frequency oscillation suspected windows is screened, and the screened continuous windows are low-frequency oscillation abnormal signals. On the basis of an existing Prony algorithm, a judgment rule of continuous window smoothness is introduced, the anti-noise performance of the algorithm is further optimized, and the accuracy and stability of low-frequency oscillation recognition are improved.

The invention discloses a multi-motor cooperative control method and system based on speed compensation, particularly relates to the technical field of industrial multi-motor control, and is used for solving the problems of compensation misalignment and system oscillation caused by an existing parameter asynchronous drift working condition. Current and voltage signals of each motor are collected in real time, and dynamic resistance and inductance parameters are calculated on line; constructing a parameter variation causal entropy network to quantify causal influence intensity of single machine abnormity on the system, and synchronously generating a system collaborative vulnerability index to realize risk penetration perception; when low-frequency oscillation is detected, harmonic components are extracted, and a sensitivity grading model of parameter mismatch and oscillation frequency is established; a dominant compensation role is distributed based on causal entropy to focus on a key disturbance source, a dynamic amplitude limiting instruction is generated according to collaborative vulnerability to adapt to system stability, and resonance suppression priorities are distributed according to sensitivity levels to optimize resource configuration; and finally, a torque instruction is reconstructed and synchronously issued, so that cross-equipment accurate transmission of compensation energy is realized, and mechanical coupling oscillation is eliminated.

A method and system for mitigating low-frequency oscillations of a power system network (PSN). The method includes receiving multiple data sets from the PSN, comprising values of terminal voltage, a real power, and a reactive power. The method further employs the multiple data sets to a fuzzy c-means clustering technique, a deep learning technique and a whale optimization algorithm to generate a pair of parameter values for a power system stabilizer controlling a steady-state of the power system network.

The invention discloses a hydroelectric generating set forced mechanism low-frequency oscillation elimination method and device, and the method comprises the steps: monitoring the power oscillation inherent frequency of a hydroelectric generating set at different load sections, and determining the resonant frequency early warning range of the pressure pulsation of a draft tube of the hydroelectric generating set according to the power oscillation inherent frequency of the hydroelectric generating set; a hydroelectric generating set combination strategy considering the vibration area is calculated to obtain the resonance adjustable load capacity, and the guide vane opening degree corresponding to each hydroelectric generating set is reversely calculated according to the resonance adjustable load capacity; when it is monitored that the hydroelectric generating set draft tube pressure pulsation frequency is within the resonance frequency early warning range and the amplitude exceeds the set value, the multiple hydroelectric generating sets are controlled to act in a coordinated mode to adjust the guide vane opening degree. Under the condition that a prime motor and a water diversion system are not changed, forced power oscillation accidentally occurring in the vibration crossing area of the large hydropower station can be rapidly eliminated.

The invention discloses a modulation method and system for suppressing common-mode voltage and midpoint low-frequency oscillation of a three-level inverter, and the method comprises the steps: obtaining a reference voltage vector, and judging a sector where the reference voltage vector is located according to the division condition of a space sector; according to the space sector division condition and the position of the reference voltage vector, a synthetic virtual vector and a corresponding basic voltage vector are obtained, and the action sequence of the basic voltage vector is determined; based on the action sequence of the basic voltage vector, virtual vector action time is calculated according to volt-second balance, the virtual vector action time is distributed to the basic voltage vector action time, and a pulse width modulation signal is output to control the on-off of a power device of the inverter, so that the common-mode voltage of the three-level inverter is suppressed, and the three-level inverter is obtained. And safe and stable operation of the system is guaranteed.

The invention discloses a doubly-fed wind power grid-connected system low-frequency oscillation control method and device, a storage medium and an electronic device, and the method comprises the steps: calculating a reactive power given value of additional damping control based on an angular velocity difference and an additional damping controller transfer function under the condition that the doubly-fed wind power grid-connected system generates low-frequency oscillation, wherein the reactive power given value is used for providing additional damping for the low-frequency oscillation frequency to suppress the low-frequency oscillation frequency; superposing the reactive power given value to an existing reactive power reference value to obtain a target reactive power reference value; and inputting the target reactive power reference value and the actual reactive power value into a proportional-integral controller of the doubly-fed wind power grid-connected system to obtain a current control instruction output by the proportional-integral controller, and adjusting the low-frequency oscillation frequency according to the current control instruction. By adopting the technical scheme, the technical problem that the suppression effect on the low-frequency oscillation of the doubly-fed wind power grid-connected system is relatively poor is solved.

The invention relates to the technical field of power grid energy storage control, and particularly discloses a network construction type energy storage system and a control method thereof, and the system comprises a parameter collection module which obtains the voltage, frequency, short-circuit capacity ratio, phase angle and other power grid operation parameters of a grid-connected point in real time; the scene recognition module judges the power grid scene of the energy storage system according to the acquired parameters, wherein the power grid scene comprises a weak power grid scene, a fault scene, an oscillation scene, a phase angle jump scene and a power loss scene; the strategy library module stores control strategies for each scene, including active / reactive control, active / reactive decoupling, overload support, low-frequency oscillation suppression, phase angle stabilization and black start strategies; and the adaptive control module retrieves and calls a corresponding strategy from a strategy library according to an identification result, performs adaptive control on the energy storage system, and realizes intelligent response and stable support for a complex power grid environment. According to the invention, intelligent response and stable support of the energy storage system to a complex power grid environment are effectively realized.

The invention discloses a virtual synchronous machine active low-frequency oscillation suppression method based on power feedback compensation, and belongs to the field of new energy grid-connected converter control under large-scale new energy access. According to the method, the output voltage and current of the new energy converter are sampled, the instantaneous output active power and reactive power are calculated, and the average output active power and reactive power are obtained through a first-order low-pass filter; and then virtual synchronous machine active outer loop control based on output power feedback compensation and reactive outer loop control based on reactive-voltage droop are adopted to obtain reference values of a d-axis voltage amplitude and a voltage phase angle of new energy converter voltage inner loop control, and output voltage closed loop control is carried out. Under the condition that the output active control order and the steady-state characteristic are not increased, the output active dynamic overshoot and low-frequency oscillation suppression of the new energy converter based on the network construction control type virtual synchronous machine are effectively realized, the parameter value range is slightly constrained by the system stability, and the engineering application is simple.

The invention discloses a multi-branch power system stabilizer suitable for a wind-thermal bundling system, which adopts a cooperative control structure in which a low-frequency branch and a subsynchronous branch are connected in parallel, and suppresses low-frequency oscillation in a frequency band of 0.1-4Hz through a second-order filtering module, a blocking compensation module and a lead-lag module of the low-frequency branch. And the subsynchronous branch extracts a subsynchronous risk mode based on an inverse transformation matrix of a generator shafting torsional vibration mode quantity, and directionally injects a damping signal in combination with a phase compensation module to suppress subsynchronous oscillation in a frequency band of 10-50 Hz. And the parallel output module performs superposition amplitude limiting on the multi-branch signals and then accesses an excitation regulator to dynamically regulate the electromagnetic torque so as to realize wide-frequency-domain oscillation suppression. Through modal quantity directional control, parameter adaptive setting and multi-branch dynamic decoupling, the problems of insufficient multi-band suppression capability, parameter mismatch, controller conflict and the like of a traditional power system stabilizer in a wind-fire coupling system are solved, and the stability and robustness of a new energy high-permeability power grid are remarkably improved.

The invention discloses a liquid cooling heat dissipation control system of a charging pile, relates to the technical field of energy storage charging piles, and solves the problems of low-frequency oscillation and energy consumption fluctuation caused by independent closed-loop adjustment of a pump and a fan and fault false alarm and failure alarm caused by fixed threshold diagnosis in the prior art. The collection module is used for synchronously collecting and filtering the cooling liquid inlet and outlet temperature, the power module temperature, the pump current and the fan rotating speed; a first prediction modeling module is adopted to generate thermal load prediction and time delay compensation parameters; constructing a self-adaptive baseline relationship between the pump flow and the heat exchange efficiency of the fan through a second baseline modeling module; performing dynamic anomaly judgment based on the residual sequence through a residual detection module; the cooperative scheduling module is used for solving the control track of the pump and the fan by combining the prediction result, the baseline parameter and the abnormal label on the basis of a model prediction control framework; according to the invention, the coordination of liquid cooling heat dissipation control and the adaptability of fault diagnosis are greatly improved.

The invention provides a method for calculating a stable margin domain of isolated network operation regulation of a pumped storage power station, which comprises the following steps of: constructing a simulation model of the pumped storage power station in an isolated network mode, and deducing a comprehensive transfer function based on the model so as to obtain a margin stability characteristic equation of a pumped storage power station regulation system; by adjusting various parameters in the pumped storage power station, any two parameters are selected as coordinate axes in a rectangular coordinate system, and the stability margin domain of the pumped storage power station adjusting system under different stability margins is calculated by utilizing the Hellzz criterion; and fitting the time domain simulation curves of the pumped storage power station at different stability margin domain boundaries by adopting a power function. The method can quantify the stability margin of the power station when the power station encounters disturbance, identifies the stability boundary of the system under the ultralow frequency oscillation condition by analyzing the stability margin under different operation conditions, can effectively prevent and reduce the instability phenomenon, and improves the overall safety and reliability of the pumped storage power station.

The invention relates to the technical field of offshore wind power grid connection, in particular to a low-frequency oscillation suppression method for an offshore wind power synchronous machine grid connection system, which comprises the following steps: acquiring inherent parameters of the synchronous machine grid connection system and active power reference instructions of each fan of an offshore wind power plant; according to the inherent parameters, control parameters of a preset damping controller are determined, and the damping controller is configured based on the control parameters; acquiring an actual operation frequency signal of the offshore low-frequency power grid in real time, and comparing the actual operation frequency signal with a preset rated frequency of the offshore low-frequency power grid to obtain a frequency deviation signal; inputting the frequency deviation signal into a configured damping controller, and outputting a damping power instruction; and superposing the damping power instruction and the active power reference instruction to generate an active power control instruction. According to the invention, the low-frequency oscillation of the new energy synchronous machine grid-connected system can be effectively suppressed, and meanwhile, the situation that the grid-connected safety is threatened due to the great fluctuation of the terminal voltage of the motor caused by suppression measures is avoided.

The invention provides a method and a system for suppressing low-frequency oscillation of a network-forming converter under a weak power grid, and the method comprises the steps: obtaining a power grid short-circuit ratio through employing a preset dual-mode identification strategy, adaptively adjusting the control parameters of the network-forming converter through a preset parameter mapping relation, carrying out the stability sufficiency verification of the adjusted control parameters, and obtaining the low-frequency oscillation of the network-forming converter under the weak power grid. After verification is passed, the adjusted control parameters are applied to a virtual synchronous machine control algorithm to execute grid-connected control, low-frequency oscillation characteristics are extracted from monitored grid-connected point frequency signals, and an enhanced suppression mechanism is triggered after the low-frequency oscillation characteristics exceed a threshold value; real-time sensing of power grid intensity, multi-parameter collaborative adaptive adjustment, active monitoring and rapid suppression of low-frequency oscillation and continuous self-learning optimization are realized, stability adequacy check is realized, and the problem of low-frequency oscillation of a grid-forming converter under a weak power grid is effectively solved.

A grid connection inverter system includes a converter, an additional damping controller, a sampling circuit, and a controller. The converter is configured to output a grid connection voltage, a grid connection current, and power to the power grid. The sampling circuit is configured to detect the grid connection voltage, the grid connection current, and a power grid frequency of the power grid. The additional damping controller is configured to output a power additional value to the controller based on the grid connection voltage and the power grid frequency when the power grid is in a low-frequency oscillation state, where the power additional value includes an active power additional value and a reactive power additional value. The controller is configured to adjust, based on the power additional value, reactive power and active power that are output by the converter.

The invention provides a speed regulator control method and system for coping with ultralow frequency oscillation, and the method comprises the steps: obtaining the frequency data of a hydropower system in real time, and carrying out the filtering processing based on the original frequency data, thereby obtaining the filtering frequency data; constructing a first discrimination vector based on the filtering frequency data, determining a current oscillation occurrence probability based on the first discrimination vector, and determining whether to start an additional damping controller of the speed regulator based on the current oscillation occurrence probability; predicting frequency data of a plurality of time points in the future based on the current original frequency data, constructing filtering frequency data corresponding to each time point based on the predicted frequency data of the plurality of time points in the future, and constructing a second discrimination vector corresponding to each time point based on the filtering frequency data of each time point; and determining oscillation occurrence probabilities at multiple time points based on the multiple second discrimination vectors, and determining whether to start an additional damping controller of the speed regulator based on the oscillation occurrence probabilities at the multiple time points.

The invention relates to a variable-speed pumped storage group power system low-frequency oscillation self-adaptive control method, and relates to the field of power control, and the method comprises the steps: processing power system operation data and energy storage group power generation monitoring power through a mode recognizer, and outputting a first low-frequency oscillation mode; when the mode belongs to the low-frequency abnormal oscillation mode, a water turbine mechanical energy prediction network is called, a mode recognizer is combined, an optimization algorithm is executed on unit control parameters, and the recommended unit guide vane opening degree, the recommended unit operation frequency and the recommended unit rotation speed set point are obtained; controlling a water turbine according to the recommended unit guide vane opening and the recommended unit operation frequency, and controlling an alternating current excitation device according to the recommended unit rotation speed set point. The technical problem that in the prior art, low-frequency oscillation control is achieved depending on adjustment of physical components, and consequently adaptability is poor is solved.

The invention belongs to the technical field of virtual synchronous generator control, and particularly discloses a VSG active power decoupling control method based on feedback control, and the method comprises the following steps: analyzing the active power and reactive power of a VSG control system according to the topological structure of the VSG control system; according to the active power and reactive power analysis results of the VSG control system, constructing a small signal model of a power loop; enabling a reactive power coupling item in the small signal model of the power loop to be equivalent to a feed-forward item in an active power control loop, and obtaining a small signal model of the active power control loop considering a coupling effect; and a feedback item FQ2 is added into the small signal model of the active power control loop considering the coupling effect, and VSG active power decoupling control is realized. The problem that low-frequency oscillation caused by power control loop coupling under a high-resistance-inductance-ratio network cannot be effectively restrained through an existing VSG control technical method is solved, the control principle is simple, and implementation is easy.

The invention provides a signal automatic patrol and abnormity intelligent analysis method and device based on a centralized control center. By constructing a patrol logic control mechanism and combining real-time data acquisition and operation trend analysis, abnormal states and potential fault symptoms occurring in the operation process of the power equipment are identified, periodic or real-time analysis is performed on the operation condition of a target object, and a patrol report and an abnormal grade division result are automatically generated. The method can achieve the intelligent recognition and response of ultralow frequency oscillation, signal fluctuation and other characteristic problems in new power system scenes such as new energy access, facilitates the improvement of the intelligent level of operation monitoring of a centralized control center, and improves the early warning capability of equipment faults and the accident response efficiency. And the operation risk and the system disturbance caused by monitoring omission are avoided.

The invention relates to the field of power systems, in particular to a method and system for improving the low-frequency oscillation suppression capability of a power system stabilizer, and the method comprises the steps: building an excitation regulator hardware-in-loop simulation platform to form a closed-loop test environment; constructing a model containing prime mover forced oscillation and generator special operation conditions; configuring simulation parameters based on the actual constant value of the unit; injecting multi-modal disturbance and acquiring a dynamic signal; calculating a multi-dimensional index for evaluating the low-frequency oscillation suppression capability of the PSS; generating a full-working-condition adaptability judgment result through a dynamic weight distribution algorithm; and if not, optimizing the PSS parameters by taking the weighted comprehensive score as a target, and repeating the test until the requirements are met. According to the invention, the problem that the low-frequency oscillation suppression capability of the traditional PSS parameter setting is insufficient under a special working condition is solved.

The invention discloses a method for analyzing low-frequency oscillation interaction between parallel direct-driven wind turbine generators. The method comprises the following steps: establishing a parallel grid-connected simulation model of two direct-driven wind turbine generators; accessing to a simulation model of an alternating current system, linearizing at a balance point to obtain a system state space equation, calculating a characteristic value and participating in factor analysis, and analyzing low-frequency oscillation characteristics of the system; according to an analysis result, aiming at a low-frequency oscillation mode related to the direct-current voltage, establishing a damping torque model of a direct-current voltage loop mode of the direct-driven wind turbine generator; forming a two-machine parallel system damping torque model by using the damping torque model, and constructing an expression of interaction between units by using a damping transfer function; quantitatively evaluating the interaction between the direct-driven wind turbine generators; after evaluation, the system is expanded to a multi-machine parallel system and the interaction is analyzed. The mutual change trend is quantitatively analyzed in the form of the mutual damping coefficient, the dynamic coupling mechanism between the parallel direct-driven wind turbine generators is clearly and quantitatively elaborated, and the problem that the interaction mechanism between the generators cannot be quantitatively analyzed in the past is solved.

The invention provides a network construction converter control method, which comprises the following steps: decoupling an original transient damping coefficient and an original primary frequency modulation coefficient which are mutually coupled in an original VSG control system to obtain an active steady-state primary frequency modulation coefficient K [omega] and an active transient damping coefficient KD, and further respectively establishing active steady-state and transient independent regulation channels; active control steady-state deviation is realized through an active steady-state primary frequency modulation coefficient K [omega], response speed control is realized by combining a controller function Gdamp (s), active transient damping coefficient KD is adjusted to be combined with a second-order filter function GLPF (s) to control active low-frequency oscillation suppression, and independent control and adjustment of active steady state and transient state are realized. The adaptability of a network-forming converter control strategy to different power grid intensities, system inertias and load characteristics is further improved, and the problems that in an existing VSG control method, the control effect coupling of an original transient damping coefficient and an original primary frequency modulation coefficient is too high, and the requirement for independent adjustment of active power dynamic and steady-state characteristics cannot be met are solved.

The invention discloses a low-frequency oscillation situation degradation suppression method and system. The method comprises the following steps: establishing a first heartbeat signal acquisition logic of a target coal-fired unit, and acquiring a first time interval according to the first heartbeat signal acquisition logic; generating a first sensing signal according to the first time interval in combination with a preset overrun judgment strategy; generating a first degradation control signal according to the first sensing signal in combination with a preset first degradation suppression strategy, and determining a first instruction and a second instruction according to the first degradation control signal; and implementing the first instruction and the second instruction to finish low-frequency oscillation situation deterioration suppression. The method not only reduces the risks of frequent action of the main regulating valve, serious network-related assessment, low-frequency oscillation deterioration and the like induced by a traditional low-frequency oscillation suppression method adopting strong and weak parameter conversion, but also guarantees the flexibility of peak regulation and frequency modulation of the unit while monitoring, suppressing and eliminating the low-frequency oscillation of the target coal-fired unit in real time.

1. The name of the product of this design: electric potential therapy device. 2. Purpose of the product of this design: This product is a potential therapy device, such as a low-frequency oscillator for living organisms, a potential therapy device for living organisms, etc. 3. The design key point of this appearance design product lies in the shape. 4. The picture or photo that best illustrates the design points: Stereoscopic diagram 1.

This invention discloses a method for designing an additional stabilizer to suppress low-frequency oscillations in a doubly-fed induction generator (DFIG) wind turbine. The method includes: constructing the input and output terminals of the additional stabilizer and designing the control loop; plotting the Bode plot of the closed-loop transfer function of the original system to determine the dominant oscillation frequency w. d and the phase lag value θ h Perform parameter tuning calculations for the phase compensation stage in the control loop; select the proportional coefficient K of the isolation stage of the additional stabilizer. e The quality coefficient ξ of the second-order bandstop filter with added stabilizer s and resonance coefficient K s Initialize the values; calculate the time δt required to suppress the disturbance and perform iterative calculations; and obtain the optimal parameter K. e ξ s and K s The values ​​are then substituted into the expressions for the isolation stage and the second-order band-stop filter. The additional stabilizer and design method for suppressing low-frequency oscillations in doubly-fed induction generator (DFIG) wind turbines provided by this invention can effectively suppress low-frequency oscillations in DFIG grid-connected systems and significantly enhance the system's stability under small disturbances.

The application discloses a kind of power system low-frequency oscillation characteristic signal extraction methods, comprising: the electrical variation data of acquisition each generator outlet is preprocessed;Through complementary ensemble empirical mode decomposition, variation data is decomposed, and noise component is filtered out;SPA smoothing algorithm is used to process the electrical variation signal after denoising;Prony method is used to decompose the signal after smoothing, and the amplitude and phase of each frequency component are extracted;The application has more excellent noise suppression capability and signal fidelity, can effectively solve the problem of modal aliasing, can adaptively identify and filter out various noise components, and shows good adaptability to noise interference under different operating conditions of power system;SPA smoothing algorithm reduces the error introduced by complementary ensemble empirical mode decomposition while effectively retaining the key features of low-frequency oscillation;Combined with Prony method, the characteristic parameters of the oscillation signal can be accurately extracted in a strong noise environment, providing a reliable data basis for low-frequency oscillation source identification.

This invention discloses a method for achieving phase-frequency synchronization based on a coupled neuron oscillator system. First, a cross-frequency nonlinear coupling model is constructed by establishing a two-connection structure based on exogenous input and local interaction in the Poincaré model. By introducing nonlinear coupling, phase-frequency synchronization of the coupled neuron oscillators is achieved. Spectral analysis is then used to determine the effect of the coupling strength between low-frequency and high-frequency neurons on phase-frequency synchronization. Theoretical analysis is then used to determine the influence of the low-frequency oscillation phase on the high-frequency oscillation frequency and its mechanism.

The invention discloses a phase-frequency synchronization implementation method based on a coupled neuron oscillator system. The method comprises the following steps: firstly, establishing two connection structures of exogenous input and local interaction of a Poincare model to construct a cross-frequency nonlinear coupling model, and introducing nonlinear coupling to realize phase-frequency synchronization of coupled neuron oscillators; and determining the influence of the coupling effect strength between the low-frequency neurons and the high-frequency neurons on phase-frequency synchronization by adopting a spectrum analysis method. And determining the influence of the low-frequency oscillation phase on the high-frequency oscillation frequency and the mechanism thereof based on theoretical analysis.

The invention discloses a measurement regulation and control method and system of an atomization tester, and aims to solve the problem that a Peltier temperature control system is easy to generate overshoot and low-frequency oscillation at a critical point. The method comprises the following steps: S1, setting a target temperature and a precision tolerance interval; s2, rapidly cooling to a dynamic switching temperature; s3, switching to a precise approaching mode, and driving a Peltier by adopting a frequency self-adaptive micro-current pulse sequence based on the residual heat to realize overshoot-free temperature positioning; and S4, when the temperature meets the steady-state conditions of the mean value, the standard deviation and the trend slope, switching to a steady-state holding mode, performing spectral analysis on the temperature sequence to distinguish high-frequency disturbance and low-frequency drift, and only applying intelligent micro-compensation subjected to nonlinear filtering to the low-frequency drift. According to the invention, through multi-stage strategy matching, pulse control based on energy prediction and intelligent disturbance identification, rapid, accurate and stable control of the temperature of the condensation plate is realized, and the reproducibility of a test result is significantly improved.

The invention discloses a method for extracting characteristic parameters of a low-frequency oscillation mode of a power system, and in the power system, a time sequence signal generally refers to records of parameters such as voltage, frequency and the like in the system along with time change. In order to effectively analyze the signals, singular spectrum analysis is firstly carried out, the singular spectrum analysis comprises the steps of converting the time sequence signals into a track matrix, then carrying out singular value decomposition on the track matrix, and reconstructing a time empirical orthogonal function obtained after singular value matrix decomposition, and at the moment, a denoised reconstructed signal is obtained; and performing matrix pencil analysis on the reconstructed signal, and extracting characteristic parameters of the low-frequency oscillation mode. In this way, the characteristic parameters of the low-frequency oscillation mode can be accurately extracted under the condition that the identification integrity is guaranteed.