3197 results about "Harmonics" patented technology

The invention discloses a data anomaly detection system and method based on power equipment, and belongs to the technical field of power system data processing and fault monitoring, and the method comprises the steps: obtaining a multi-dimensional operation parameter sequence of voltage, current, temperature, harmonic waves, switching states, topological energy transfer vectors and the like; constructing a local disturbance response map, extracting a micro-disturbance driving factor, and generating a high-dimensional feature embedding matrix; constructing a multi-scale state density map on the basis of the embedded matrix, and mapping an equipment behavior evolution track; introducing a coupling evolution path tracking algorithm based on the density map, identifying an abnormal state set, and constructing a cross-time-period risk channel; matching the current monitoring data with the risk channel, and calculating a risk evolution value; when the value exceeds a set threshold value, abnormal early warning is triggered, and an evolution path model is output; the method has the advantages of high accuracy, strong trend identification capability and early warning, and is suitable for intelligent operation and maintenance of power equipment under complex working conditions.

The invention discloses an electrical fire monitoring method based on inherent residual current automatic compensation, and relates to the technical field of electrical safety monitoring, and the method comprises the following steps: S100, collecting a residual current signal, executing multi-component time-frequency deconstruction processing, extracting an energy distribution characteristic through wavelet packet transformation, and extracting a mutability index in combination with short-time spectrum entropy analysis, and constructing a preliminary distribution map of higher harmonic interference, and determining boundary features of interference signals in a time domain and a frequency domain. According to the method, high-frequency interference signals are accurately positioned through time-frequency deconstruction, wavelet packet analysis and spectral entropy indexes, non-fault harmonic components are effectively eliminated in combination with amplitude-frequency coupling recognition and a recursive rejection strategy, closed-loop control is constructed by introducing an adaptive compensation and stability backtracking mechanism, accurate recognition and dynamic correction of real electric leakage risks are achieved, and the method is suitable for large-scale popularization and application. The identification precision and the safety reliability of the monitoring system in a complex industrial environment are obviously improved, and the method has good engineering adaptability.

The invention discloses a virtual synchronous generator grid-connected current harmonic suppression method and system, and relates to the technical field of power systems, and the method comprises the steps: S1, carrying out the digital sampling of intermittent high-frequency disturbance through a wind power plant grid-connected current signal in a power grid through an analog-to-digital converter, and obtaining an original digital current sequence; s2, according to the original digital current sequence, analyzing a wind load frequency component by adopting a fast Fourier transform algorithm, and determining amplitude and phase characteristics of a high-frequency harmonic component; s3, if the amplitude of the high-frequency harmonic component exceeds a preset threshold value, extracting an intermittent disturbance harmonic sequence from the frequency component to obtain a to-be-suppressed harmonic subset; according to the virtual synchronous generator grid-connected current harmonic suppression method and system, the stability of a remote wind power plant power grid is remarkably improved, continuous monitoring and real-time suppression of intermittent disturbance are achieved, and high efficiency and reliability of power grid operation are guaranteed.

The invention relates to the technical field of electrical monitoring, provides a general generator electrical monitoring system with a fault self-diagnosis function, and aims to deeply excavate potential correlation between electrical and mechanical parameters by judging a coherence coefficient and a phase difference between a current harmonic component and a bearing vibration frequency band and marking a fault coupling identifier by using a coupling mode library. Electrical and mechanical coupling faults can be accurately identified, and the identification capability of complex faults can be greatly improved; meanwhile, the diagnosis threshold is dynamically adjusted in combination with the load rate and the winding temperature, so that the system can better adapt to different operation conditions of the generator, and the diagnosis accuracy and reliability are improved; the fault causal chain is analyzed through the causal inference algorithm, and the fault source is positioned, so that compared with the existing fault tracing mode lacking systematicness, the fault generation reason and process can be analyzed more comprehensively and deeply, the fault source can be positioned quickly and accurately, operation and maintenance personnel can take targeted measures in time, and the fault tracing efficiency is improved. And the operation safety and reliability of the generator are improved.

The invention discloses an intelligent operation and maintenance fault early warning method for a rail transit variable-frequency power supply, and relates to the technical field of power electronics and intelligent operation and maintenance, and the method comprises the following steps: setting a multi-point synchronous collection device to carry out the high-precision real-time collection of voltage and current signals of a variable-frequency power supply system, and carrying out the digital coding processing of data; and performing frequency domain analysis on the acquired voltage and current signals by using a preset spectrum analysis algorithm, and extracting harmonic amplitudes and phase characteristic parameters of different orders. According to the invention, through high-precision synchronous acquisition and spectrum analysis, rapid and accurate identification of harmonic abnormity is realized; a machine learning model and dynamic threshold adjustment are fused, and the adaptability and intelligent recognition capability of the system to fault modes under multiple working conditions are enhanced; and a trend prediction and graphical early warning platform is introduced, so that the fault risk is pre-judged in advance and visually responded, and the operation and maintenance efficiency and the operation safety of the rail transit power supply system are remarkably improved.

The invention discloses a multi-scene cooperative control method, device and equipment for a network construction type energy storage converter, and a storage medium, relates to the technical field of converter control, and discloses the multi-scene cooperative control method for the network construction type energy storage converter, and the method comprises the steps: obtaining the state data of a power grid, determining grid-connected point power, power grid frequency, power grid voltage and power grid harmonic frequency spectrum according to the power grid state data; establishing a multi-objective optimization function, an energy storage system charge state constraint and a converter output current constraint based on the grid-connected point power, the power grid frequency, the power grid voltage and the power grid harmonic spectrum; and performing multi-objective optimization solution based on the multi-objective optimization function, the charge state constraint of the energy storage system and the output current constraint of the converter to obtain a fundamental current reference value and a harmonic current limit value so as to control the output current of the grid-forming type energy storage converter. According to the scheme of the invention, the capacity conflict between network construction type control and harmonic suppression can be solved.

The invention relates to the technical field of power grid monitoring, and discloses a voltage sensor multi-parameter real-time monitoring method and device in an Internet of Things environment. According to the method, real-time voltage fluctuation data of a target area is acquired by deploying a multi-channel voltage sensor array and is transmitted to an edge computing node; dynamic feature extraction is executed in the edge nodes, and a multi-dimensional feature matrix containing voltage fluctuation ratio, harmonic distortion and phase deviation features is generated; identifying voltage sag, overvoltage and harmonic resonance event characteristics based on an anomaly detection model; spatial correlation modeling is carried out in combination with power grid topological structure parameters, the coupling strength of adjacent sensor node parameters is calculated, and a multi-parameter correlation map containing event propagation paths and influence ranges is generated; inputting the voltage into a diagnosis model to generate a power grid state diagnosis report, and dynamically adjusting the sampling frequency and filtering parameters of the voltage sensor according to the power grid state diagnosis report. According to the method, real-time monitoring and analysis of multiple parameters of the power grid can be realized, and comprehensive support is provided for power grid state evaluation.

The invention belongs to the technical field of electrical safety, and particularly relates to a human body electric shock protection method and system based on multi-parameter fusion, multi-dimensional characteristic parameters are formed by extracting a high-frequency harmonic component, a voltage abrupt change slope and a magnetic field intensity fluctuation value of a residual current waveform, and the weight is dynamically adjusted according to the instantaneous change rate of each characteristic, so that the human body electric shock protection is realized. Generating a weighted feature vector; and a comprehensive criterion value is calculated in combination with a preset rule base and is compared with a dynamic threshold value, so that whether the circuit breaker is triggered to act or not is determined. According to the method, through fusion analysis of a plurality of physical characteristics, the identification capability of the system in a complex electromagnetic environment is improved, the probability of misoperation caused by external interference is effectively reduced, the action accuracy and stability of the circuit breaker are improved, and the power utilization safety and the power supply continuity are guaranteed.

The invention provides a method and system for achieving elevator energy feedback data communication. The method comprises the steps that multi-modal data are collected, and fault features are extracted, encrypted and packaged; and after decryption, phase deviation of elevator operation and power grid voltage is calculated by utilizing an algorithm, a current phase is synchronously fed back, and a feedback instruction is generated. Uploading the harmonic suppression parameter to an energy center, calculating a demand, generating a region-level feedback strategy, dynamically distributing a feedback power upper limit, synchronizing the harmonic suppression parameter, and obtaining region-level feedback data. And aggregating feedback data, and setting a global optimization target, including cost minimization, feedback maximization and carbon emission reduction. And calculating feedback energy and carbon integral according to a target adjustment algorithm, automatically settling to an operator account, and adjusting the target of the next period. Through an algorithm and an optimization mechanism, the problem of energy waste of a brake resistor in a traditional feedback technology is solved, the feedback efficiency is improved, and energy waste is reduced.

The invention relates to the technical field of vibration and noise control, discloses a new energy automobile motor high-frequency vibration and noise active suppression system and method, and aims to solve the problems of poor high-frequency vibration and noise suppression effect, real-time performance, adaptive capacity and system cost complexity of an existing new energy automobile motor. The method comprises the following steps: acquiring and preprocessing motor operation state data, extracting high-frequency harmonic characteristics, and generating predicted harmonic characteristics in combination with working condition prediction; and superposing the self-adaptive compensation quantity to a motor voltage instruction, and driving an inverter through pulse width modulation to realize active suppression of high-frequency vibration and noise. The system comprises a data acquisition preprocessing module, a harmonic feature extraction module, a working condition sensing prediction module, a self-adaptive compensation quantity generation module and a pulse width modulation correction module. By the adoption of the technical scheme, efficient, real-time and self-adaptive suppression of high-frequency vibration and noise of the motor can be achieved, the level of the high-frequency vibration and noise is remarkably reduced, the driving comfort is improved, and the complexity and cost of the system are optimized.

The invention relates to the technical field of power system testing, in particular to a transformer simulation test current optimization method based on dynamic impedance matching, which comprises the following steps: performing low-power scanning on a tested transformer to establish a nonlinear model capable of predicting harmonic waves; actively synthesizing the virtual impedance of the target power grid; and a feed-forward compensation current is generated by using a harmonic prediction model and is injected into the transformer after being superposed with a fundamental wave instruction. According to the method, accurate identification modeling is carried out on nonlinear characteristics of a tested unit, active synthesis of virtual impedance of a target power grid is combined, and harmonic compensation current is generated in real time by utilizing a feedforward control thought so as to optimize finally injected test current. According to the method, the problems of inaccurate power grid simulation and insufficient nonlinear response coupling of the transformer in a traditional test are solved, high-fidelity current injection is realized, real electrical behaviors of the transformer under various complex power grid working conditions can be accurately simulated, and the flexibility, accuracy and safety of the test are remarkably improved.

The invention discloses a detection system for operation abnormity of an electric drive axle motor of a new energy commercial vehicle, and belongs to the technical field of motor abnormity detection. The system comprises a multi-source sensing module, a dynamic coupling analysis module, a harmonic distortion traceability module, a dynamic stability analysis module, an anomaly fusion decision module, a self-adaptive threshold generation module and a fault tree reasoning module. Multi-dimensional signals such as current, vibration, temperature and a rotor position angle are synchronously acquired through the multi-source sensing module, and multi-physics field collaborative analysis is performed through the dynamic coupling analysis module and the harmonic distortion traceability module, so that the fault diagnosis accuracy of operation abnormity of the electric drive axle motor of the new energy commercial vehicle is improved; the problem that in the prior art, detection only depends on a single physical quantity, and misjudgment or missing detection is easily caused by interference is solved.

The invention relates to the technical field of prediction algorithms, and discloses a high-precision active power filtering and prediction algorithm for a three-phase ammeter, which comprises the following steps: acquiring original signals of three-phase voltage and current for baseline correction, performing time-frequency analysis on non-stationary harmonic waves and noise of the original signals, and dynamically adjusting filtering parameters; voltage and current phase alignment is carried out through FIR phase shift and zero crossing point detection, a phase-locked loop is constructed by using GRU to track the frequency of a power grid, the sampling frequency is dynamically adjusted, and frequency mutation is detected; iapFFT transformation is optimized to suppress spectrum leakage, a phase error is corrected through a deep learning network, and weak harmonic detection is enhanced by using an attention mechanism; classifying harmonic waves, and adaptively calculating total active power; dimensionality reduction is carried out on historical power and environmental parameters through an auto-encoder, and future active power is predicted; low-power-consumption hardware is adapted, and training efficiency and data security are optimized; three-phase signals are processed in parallel, and FPGA storage and FFT / FIR cores are optimized for filtering processing; and dynamically adjusting parameters of the phase-locked loop.

The invention relates to the technical field of electrical variable measurement, in particular to a rolling mill speed reducer monitoring and diagnosing system based on multi-source information fusion, which comprises an electrical parameter signal acquisition module for acquiring continuous readings of three-phase voltage and three-phase current of a rolling mill driving motor and synchronizing the readings. According to the method, the three-phase voltage and current data of the rolling mill driving motor are synchronously acquired, and the amplitude and phase are calibrated, so that a more accurate calibration electrical measurement set is obtained, and error propagation in a signal acquisition stage is effectively avoided; using the calibrated electrical data to directly calculate instantaneous input electric power, deducting motor loss to obtain an accurate motor shaft power sequence, and then using a Fourier transform method to extract key harmonic characteristics in a shaft power spectrum; and meanwhile, band-pass filtering and Hilbert transform analysis are carried out on the motor stator current, so that a clearer and more recognizable spectrum kurtosis value is obtained, and the judgment capability of current impact and periodic characteristics is enhanced.

The invention relates to a reconfigurable battery energy storage system grid-connected and off-grid seamless switching control method and device. The method comprises the following steps of: sensing a real-time power grid state, pre-judging a system operation mode, and acquiring a millisecond-level panoramic information flow of the power grid state through a high-speed sampling voltage sensor, a high-speed sampling frequency sensor, a high-speed sampling phase sensor and a high-speed sampling communication interface. And pre-judging the stability and disturbance trend of the power grid through a deep learning algorithm, executing a power distribution and voltage support algorithm in grid-connected and off-grid modes, and calculating an optimal switching opportunity point and a system reconstruction target topology scheme. Meanwhile, the harmonic distortion rate and the voltage sag depth are calculated in real time through discrete Fourier transform, so that a mode pre-judgment mechanism is automatically triggered. After switching, key parameters such as voltage, frequency and power are automatically corrected through real-time sampling and observation, and zero-sensing switching is achieved. The method can effectively improve the response speed and stability of the battery energy storage system when the power grid fails, and guarantees the safe operation of the power grid.

The invention discloses a new energy access lower harbor area transformer insulation performance and service life evaluation method, which comprises the following steps: firstly, establishing a wind and light storage AC / DC hybrid micro-grid equivalent simulation model, and quantifying a composite action mechanism of new energy fluctuation and harmonic characteristics on dynamic loss and hot-spot temperature rise of a transformer; analyzing a harmonic loss mechanism of the transformer in different operation modes; secondly, constructing a quay crane and field crane operation simulation model, and analyzing the harmonic characteristics of bridge crane equipment and the influence of the harmonic characteristics on the harmonic distortion rate of the power distribution network; then, on the basis of the data, a transformer hot-spot temperature dynamic calculation model is established in combination with bidirectional power flow characteristics; and finally, calculating transient temperature distribution of the transformer through a flow field-temperature field coupling method, and constructing a multi-physical field coupled insulation aging rate model to realize evaluation of the residual life of the transformer. The method solves the problem that the traditional method cannot quantify the bidirectional power flow and harmonic wave composite aging effect.

The invention relates to the technical field of power system monitoring and fault diagnosis, and particularly discloses a fault diagnosis system of an electrical variable measurement insulator detection device. The system comprises a synchronous acquisition module, a multi-physical field feature extraction module, a self-adaptive fault diagnosis engine and a feedback module. By synchronously acquiring voltage harmonic waves, leakage current and temperature data, extracting feature vectors of coupling electric-thermal influence and performing two-stage collaborative diagnosis by using a dynamic threshold value and a mahalanobis distance, high-sensitivity and self-adaptive accurate identification and early warning of an early latent fault of the insulator are realized. According to the system, by constructing a synchronous data acquisition module and a multi-physical field feature extraction module, two key influence factors, namely an operation voltage harmonic component and an environment temperature, are brought into a diagnosis system in a quantifiable feature form for the first time.

The invention belongs to the technical field of fault early warning, and discloses a heater fault early warning method and system based on current analysis. Comprising the steps that transient current signals of all heating wire loops in the copper bush heater are collected in real time, harmonic characteristic parameters are extracted, and a dynamic current fingerprint database and a multi-dimensional harmonic characteristic spectrum are generated respectively; dynamically calculating the contact impedance between each heating wire and the copper sleeve groove according to the dynamic current fingerprint database and the multi-dimensional harmonic characteristic spectrum; the current distribution path of each heating wire in the copper sleeve groove is restored in real time, the abnormal contact form of each heating wire is identified, the falling risk probability and falling risk strength of each heating wire are dynamically predicted by fusing the falling precursor signals of each heating wire detected in real time, and a grading early warning strategy report is generated in real time; according to the invention, fault early warning can be converted into preventive maintenance from post-maintenance, the intelligent level of operation and maintenance of the heater is improved, and the continuity and safety of production are guaranteed.

The invention relates to the technical field of on-load voltage regulation, in particular to a transformer on-load voltage regulation control method. According to the technical scheme, the transformer on-load voltage regulation control method comprises the following steps that S1, a transformer cluster running in parallel is decomposed into distributed intelligent nodes, and each node executes local voltage prediction and constraint condition management; s2, adopting a distributed model prediction control framework, and cooperatively solving a voltage regulation optimization target through an edge calculation unit; s3, a harmonic disturbance signal with a preset amplitude is injected into the transformer, equivalent impedance is dynamically identified based on response data, and virtual impedance compensation is triggered; and S4, establishing a hierarchical cooperative control architecture, and realizing clock synchronization, dynamic weight distribution and multi-objective optimization decision among nodes. Through a cooperative mechanism of distributed predictive control and dynamic impedance compensation, the response speed and the regulation precision of the on-load voltage regulation system to the power grid voltage fluctuation are remarkably improved, and the voltage out-of-limit problem under the complex working conditions of new energy grid connection, load sudden change and the like is effectively solved.

The invention relates to the technical field of electricity data analysis, in particular to an electricity meter electricity data analysis method and system.The method comprises the steps that multi-source electricity meter data such as voltage waveforms and current harmonics are collected, and then multi-mode preprocessing is conducted on original data; then, constructing a dynamic characteristic matrix which covers a time domain, a frequency domain and a load mutation characteristic; analyzing by utilizing a CNN-LSTM hybrid model through feature fusion of expansion convolution, a bidirectional LSTM network with an attention mechanism and dynamic weight distribution; model parameters are updated through a self-adaptive optimization strategy based on online learning, transfer learning and combination of equipment aging coefficients, and finally the electricity utilization safety risk grade map, the equipment energy efficiency optimization suggestion scheme and the abnormal electricity utilization behavior time-space distribution thermodynamic diagram are output to a visual terminal. The electricity consumption data of the electricity meter can be comprehensively and accurately analyzed, and powerful support is provided for power management and user electricity consumption.

The invention provides a fault diagnosis system of an intelligent bamboo cutting machine, which relates to the technical field of mechanical engineering and comprises a feature extraction module used for collecting current and voltage of a motor, a spindle vibration frequency spectrum and dynamic parameters of a quadrilateral monitoring area formed by a spindle bearing, a transmission gear box, a cutter clamping end and a base supporting part in real time, and a current waveform characteristic value, a voltage harmonic component, a vibration frequency domain energy distribution parameter and an abnormal parameter combination in the quadrilateral region are extracted. Through cooperation of multiple modules, parameter acquisition, material-load analysis, dynamic threshold setting, graded early warning and accurate fault diagnosis are realized, and the operation and production continuity of the bamboo cutting machine can be efficiently guaranteed.

The invention belongs to the technical field of transformer evaluation, and particularly relates to a harbor area transformer bearing capacity evaluation method, which comprises the steps of S1, analyzing voltage and current distribution characteristics and a harmonic component propagation rule of a harbor area microgrid under high-proportion new energy access; analyzing a change rule of a winding leakage magnetic field, an iron core magnetic flux density and winding and iron core loss; s2, calculating the hot spot temperature of the transformer in each historical time period; s3, calculating the predicted residual service life Tb and the predicted actual total service life Tins of the transformer; s4, calculating an aging coefficient B and a primary health index H1 of the transformer; s5, calculating a comprehensive health index Hcom of the transformer; s6, calculating a final health index H of the transformer; s7, if H reaches a preset threshold value, equipment is replaced; and if not, reversely deducing and predicting the residual life Tb1. According to the method, the operation state of the transformer can be accurately evaluated under the working condition of frequent power flow switching.

The invention discloses a current harmonic disturbance suppression method and suppression system for a permanent magnet synchronous motor. The method comprises the following steps: acquiring voltage and current signals of an electrical loop phasor test in the operation of the motor; an inductance identification algorithm based on high-frequency response is adopted, high-frequency excitation signals are injected, current response is monitored, and stator inductance parameters are calculated; constructing a multi-synchronous rotating coordinate system based on the parameter, and decomposing the current signal to obtain each harmonic current component; building a fuzzy full-order sliding mode observer, inputting an inductance parameter, voltage data and a harmonic current component, and dynamically adjusting a sliding mode surface parameter to observe the position and the rotating speed of a rotor; independently controlling each harmonic current adjusting channel under a multi-coordinate system in combination with observation information, and generating a compensation control signal; and the synthesized master control signal is output to the driving circuit. The system comprises six units, and the method and the system can accurately obtain parameters, efficiently decompose harmonic waves, accurately observe states, realize multi-frequency harmonic disturbance suppression, and improve motor operation stability and efficiency.

The invention belongs to the technical field of power electronics of power supply or power distribution, and provides a control method of a three-phase four-wire inverter, a controller and an inversion control system. A first control component is generated by using a phase angle, an inversion side three-phase current sampling value and a proportional integral compensator; a second control component and a third control component are generated by using a power grid voltage angular frequency, a neutral line current sampling value, a repetitive controller and a proportional resonance controller, the three control components are combined to control an inverter power switch tube, a proportional integral compensator is still adopted, the algorithm is simple, parameters are easy to design, and the reliability is high. And meanwhile, a repetitive-proportional resonance (RC-PR) composite controller is utilized to realize suppression of neutral line fundamental wave and harmonic current, and the method has faster dynamic response to load abrupt change, so that optimization of dynamic performance and steady-state performance is realized.

The invention relates to the technical field of power systems, and discloses a voltage regulation system of reactive power compensation equipment, which is characterized in that harmonic interference is filtered and eliminated through a voltage reactive power sensing unit, and accurate power grid parameters are acquired; a load trend pre-judgment unit analyzes the historical load curve and the real-time change trend to generate a future pre-judgment signal; the dynamic compensation calculation unit combines the current power grid state with the prediction to calculate the optimal compensation capacity and generate a switching instruction, after the hybrid switching actuator receives the instruction, a thyristor is triggered firstly to realize inrush current-free conduction, a contactor is switched to maintain low power consumption after the current is stable, and meanwhile, the compensation state monitoring unit performs closed-loop adjustment on parameter deviation, so that the optimal compensation capacity is obtained. The multi-dimensional protection unit prevents overvoltage, overcurrent and overheating, the double-path power supply guarantees continuous operation when the main power supply is abnormal, the intelligent communication unit realizes data uploading and remote cooperation, quick response switching of reactive compensation equipment and guarantee of safety of a large-scale power grid are realized, and inrush current impact in the switching process is effectively inhibited.

The invention discloses a remote real-time monitoring and fault early warning method for a power supply operation state, and relates to the technical field of power electronics and energy management, and the method comprises the steps: collecting the temperature data of a key part of a power supply through an optical fiber Bragg grating sensor array, and analyzing the wavelength offset; electrical parameters are collected through a differential MEMS current / voltage sensor, and a permalloy / ferrite composite shielding layer is arranged in the sensor; collecting a mechanical vibration signal through a piezoelectric ceramic vibration sensor; for device data from different manufacturers, Modbus and CAN heterogeneous protocols are matched and analyzed through a regular expression, and the Modbus and CAN heterogeneous protocols are converted into a unified RDF triple format; inputting temperature, current and vibration data into a space-time alignment module, and constructing a semantic mapping relation by adopting an ontology; calculating a sensor confidence coefficient weight, and performing weighted fusion to generate an equipment health index; operating a lightweight LSTM model at an edge node, and detecting current harmonic and vibration resonance frequency band abnormity in real time; cOMSOL multi-physical field simulation is combined at the cloud end, and the evaporation rate of the capacitor electrolyte is predicted.

The invention discloses an intelligent charging pile core module based on a VIENNA structure, an electric energy quality management method, system and equipment and a storage medium, and belongs to the field of electric power system energy storage equipment.The intelligent charging pile core module based on the VIENNA structure comprises the steps that an integrated power conversion unit is constructed, the power conversion unit adopts a VIENNA rectifier topology, three-phase alternating current is converted into direct current, and the direct current is converted into direct current; a harmonic suppression structure linked with the control interface is arranged; state information in the operation process is collected and serves as input of the control strategy module; based on the state information, a modulation control instruction is generated in the control strategy module to drive the switching action of the power conversion unit; on the basis of the modulation control instruction, the switch control is executed, meanwhile, the direct-current side midpoint potential of the power conversion unit is synchronously adjusted, and the distribution of direct-current bus capacitor voltage is controlled; and identifying the current operation condition according to the state information, switching to a control template corresponding to the operation condition in the control strategy module, and generating a modulation control instruction.

The invention discloses an intelligent control method and system for a motor driver, and the method comprises the steps: building an acoustoelectric incidence matrix through collecting harmonic current and sound pressure fluctuation data in the operation process of a motor, and forming a fault feature library; identifying an available fault mode to determine an energy collection point, and performing phase deviation processing on the collection point to generate an auxiliary driving signal; performing spectrum analysis on the sound pressure fluctuation data to obtain an acoustic characteristic spectrum, extracting an efficiency indication tone through characteristic decomposition, mapping the efficiency indication tone into a torque optimization parameter, and establishing a noise reduction control table; performing spectrum analysis on the enhanced control domain to identify a high-energy frequency band, executing a frequency shift operation to generate a safety frequency band signal, and forming a multi-frequency band management strategy in combination with a noise reduction control table; a management strategy is decomposed into parallel control flows for sequential staggered arrangement, and an energy-saving control matrix is generated; and generating a PWM control signal based on the matrix, carrying out edge reconstruction, and obtaining a softened edge waveform through an anti-resonance injection technology to complete intelligent control of the motor driver.

The invention discloses a lightning arrester on-line monitoring method and device, and relates to the field of intelligent monitoring, and the method comprises the steps: firstly collecting original current and voltage waveform data, carrying out the frequency domain decomposition operation, then introducing an intelligent prediction mechanism, carrying out the intelligent prediction of a phase error based on the fundamental voltage phase, temperature change and harmonic characteristics, and finally, carrying out the calculation of the phase error. And performing phase angle correction operation and preliminary calculation of resistive current on the fundamental current and voltage by using the corrected phase information, and introducing a historical data smoothing algorithm to perform noise reduction optimization on a result. And finally, comparing the analyzed and processed resistive current with a preset threshold value, and judging whether an alarm prompt is generated or not. Therefore, real-time evaluation and abnormal alarm of the operation state of the lightning arrester are realized, so that a powerful guarantee is provided for safe operation of a power system.

The present invention provides a method for cooperatively suppressing a common-mode voltage and current harmonics of coupled three-level inverters, comprising: based on amplitude and phase angle of reference voltage vector, determining sector and region in which the reference voltage vector is located; selecting four basic voltage vectors with low common-mode voltage amplitudes to synthesize the reference voltage vector; writing volt-second balance equation based on selected basic voltage vectors, and calculating duty cycles thereof; and based on sector and region in which reference voltage vector is located, set value of voltage difference across capacitors on direct current side, and actual value of voltage difference across capacitors on direct current side, (1) updating duty cycles of basic voltage vectors, to realize separate control of capacitor voltage; and (2) designing and converting switching sequence into PWM drive signal of power switch, to control the coupled three-level inverter to operate.