6446 results about "Three-phase electric power" patented technology

The invention relates to the technical field of power system fault monitoring, and discloses a 10kV voltage transformer ground fault real-time monitoring method and system, and the system comprises a ground fault data collection module, a waveform distortion analysis module, a transient signal detection module and the like. Three-phase current, zero-sequence current and voltage waveform data are collected, a current harmonic component proportion, a zero-sequence current high-frequency transient energy value and the like are analyzed, a fault type is determined by combining a phase difference, and a fault position is positioned according to topological parameters and line impedance. And the temperature of the grounding down lead can be monitored, and the fault probability is evaluated and the threshold value is dynamically adjusted by machine learning. According to the invention, real-time accurate monitoring can be realized, fault types and positions can be accurately diagnosed, potential hidden dangers can be comprehensively monitored, the intelligence of a monitoring system is improved, the operation and maintenance cost and risks are effectively reduced, and safe and stable operation of the 10kV power distribution network is ensured.

The invention discloses a power distribution management system of an intelligent charging pile, and belongs to the technical field of electric vehicle charging facilities and intelligent power grids. The load prediction module carries out space-time alignment fusion on historical data and real-time monitoring data to generate a power distribution demand prediction value, and the edge calculation controller executes a model prediction control algorithm based on multi-source data to generate a real-time control strategy containing relay time sequence parameters and a capacitance compensation scheme. And the dynamic power distribution adjustment module executes strategy parameters through the solid-state relay array and the parallel compensation capacitor bank. Self-adaptive adjustment of the power distribution network is achieved through a real-time monitoring-prediction-optimization closed-loop control mechanism, the harmonic content of the power grid is effectively reduced, the energy distribution efficiency of the charging pile group is improved, and the method is suitable for intelligent electric energy management of public charging stations and other scenes.

The invention relates to the technical field of power operation and maintenance, in particular to a power system operation and maintenance method and system of an intelligent power distribution cabinet for weak current control. The method comprises the following steps: acquiring power operation data and sensing data of a power distribution cabinet, and analyzing a topological structure of a power system to obtain a dynamic topological structure of the power system; performing potential load anomaly analysis on the sensing data of the power distribution cabinet to obtain load anomaly node data of the power system; performing load anomaly influence structure division based on the load anomaly node data of the power system to obtain load anomaly influence nodes; performing abnormal node classification on the load abnormal influence nodes according to the sensing data of the power distribution cabinet to obtain three-phase power load offset nodes and three-phase power improper wiring nodes; and performing power distribution reconstruction on the three-phase power load offset node and the three-phase power improper wiring node to obtain abnormal node power distribution data. According to the invention, the weak current control efficiency and the power distribution energy efficiency can be improved.

The invention relates to a multi-source data electric energy quality energy-saving operation monitoring method and device based on AI Internet of Things, and the method comprises the steps: obtaining a transient electromagnetic signal of a permanent magnet operating mechanism circuit breaker, and extracting a time sequence characteristic parameter of the transient electromagnetic signal; judging whether a harmonic problem caused by an inverter exists or not and whether voltage suddenly rises or drops or not, and determining whether the time sequence characteristic parameters are associated with power quality disturbance or not; acquiring a voltage jump amplitude and a voltage swell rate to obtain a voltage fluctuation degree, and outputting a discharge strategy of the energy storage system through a pre-established discharge optimization model; respectively calculating to obtain a voltage distortion rate and a three-phase voltage unbalance degree, and selecting a charging strategy of the energy storage system through a pre-established charging optimization model; predicting a sudden rise rate and a sudden drop rate of the sample to obtain a prediction result, and forming an energy-saving optimization scheme of an energy storage charging and discharging strategy according to the prediction result; the charging and discharging power of the energy storage pool is automatically adjusted, an energy-saving optimization scheme is formed, and the stability of a power grid is effectively improved.

The invention relates to the technical field of CT induction power supplies, in particular to a CT induction power supply system based on cooperative control and distributed optimization and a control method. According to the technical scheme, the CT induction power supply control method based on cooperative control and distributed optimization comprises the following steps: S1, deploying a multi-mode sensing array, and synchronously collecting a three-phase current harmonic spectrum of a power supply node, an iron core magnetostriction vibration waveform and a radiator surface infrared thermal image; generating a digital twinborn body with space-time relevance through multi-physics field coupling modeling; and S2, constructing a data fusion engine driven by a space-time attention mechanism at an edge computing node, and carrying out LSTM feature extraction on the output of the step S1 and a historical operation log under physical constraint. According to the method, through collaborative innovation of multi-mode federated learning and physical embedded edge calculation, a multi-physical field dynamic modeling mechanism under privacy protection is constructed, and the correlation precision and information security of electromagnetic-vibration-thermodynamic data are effectively balanced.

The invention discloses an automatic anchor point searching and processing method for grid-connected test data of a photovoltaic inverter, and belongs to the technical field of automatic test of a power system. According to the method, a three-phase voltage and current signal output by a power grid simulator and an inverter power instruction signal are aligned through a high-precision time synchronization device; wavelet transform multi-scale noise reduction and moving average filtering combined preprocessing is adopted to improve the signal-to-noise ratio; identifying a voltage zero crossing point candidate set, a drop starting point candidate set and a recovery termination point candidate set based on a self-adaptive dynamic threshold value; transient energy characteristic verification is introduced for a voltage drop starting point; effective anchor points are confirmed through time window association of power instruction step changes. According to the method, the problems of low efficiency of manual key event point identification, misjudgment caused by noise interference, grid event and inverter response time sequence correlation missing and the like are solved, and the automation degree of test data analysis, anchor point positioning precision and control response time sequence analysis reliability are remarkably improved.

The invention discloses a VSG-based energy storage converter three-parameter coordinated adaptive control method, which comprises the following steps of: acquiring three-phase voltage and current of a VSG output port and three-phase voltage data of a grid-connected point, and calculating an output power difference, an output power change rate and a power grid angular frequency difference of the VSG; the power instruction is corrected by combining the power instruction and the power grid angular frequency difference, and the adjustment process of the VSG is divided into six stages according to a power fluctuation curve; the rotational inertia, the virtual damping and the virtual inductance are adjusted according to the power difference and the power change rate in the six stages; the virtual inductor is finely adjusted by combining the VSG output power difference and the output power change rate, and smooth transition of the virtual inductor and smooth adjustment of the power are achieved; the value of the virtual inductance is compared with the initial value of the virtual inductance, and the virtual impedance is subjected to initial value regression operation, so that the power equalization and the system stability of the parallel VSG are not influenced. The method has obvious effects on power oscillation suppression and dynamic performance improvement of the energy storage converter system based on the VSG.

The invention relates to the technical field of power electronics, in particular to a control method for a low-voltage intelligent reactive compensation system of a submerged arc furnace. Comprising the following steps: acquiring three-phase voltage, current, power factor, harmonic content and temperature parameters of the low-voltage side of the submerged arc furnace through a sensor network; the load fluctuation of the submerged arc furnace in the future 1-5 minutes is predicted based on a deep learning algorithm, and a compensation demand pre-judgment value is generated; according to a load prediction result and a real-time working condition, performing dynamic switching from three modes of fixed compensation, grouped switching and continuous adjustment; harmonic component dynamic tracking compensation is carried out by combining an active power filter (APF) and a static var generator (SVG); the system overvoltage, overcurrent and temperature parameters are monitored in real time, and a grading protection mechanism is triggered and fed back to the compensation strategy adjusting module. The invention provides a control method for a low-voltage intelligent reactive compensation system of a submerged arc furnace so as to improve the response speed of the system, prolong the service life of equipment and guarantee the electric energy quality of a power grid.

The invention discloses a low-voltage ride-through control method of a flywheel energy storage system, which is based on a low-voltage ride-through control strategy of model predictive current control (MPCC) so as to improve the low-voltage ride-through capability of the flywheel energy storage system when a power grid fails. A future current value is predicted through system modeling and a prediction algorithm, so that effective control is realized. The MPCC-based machine side-power grid side coordination control strategy can quickly respond to the voltage sag of the power grid, provide reactive power support, stabilize the voltage of the direct current bus, and ensure the safe and reliable operation of the flywheel energy storage system during the voltage sag period of the power grid. A traditional pulse width modulation (PWM) technology is abandoned, the optimal switching state is directly selected through a limited control set, and hardware implementation of a power grid side converter is simplified. A differential control strategy aiming at a power grid symmetric fault (three-phase voltage sudden drop) and an asymmetric fault (single-phase grounding) is provided, the method is suitable for a complex power grid fault scene, and the system universality is improved.

The invention relates to the technical field of adaptive control, in particular to an electrical automation adjustment method and system, and the method comprises the following steps: obtaining a three-phase current signal, collecting single-cycle high-frequency sampling, extracting an instantaneous extreme point, recording a time coordinate and an amplitude value, calculating a time interval and a change rate, screening the distribution of the extreme point, and obtaining a harmonic distortion characteristic parameter. According to the method, on the basis of high-frequency sampling, instantaneous extreme point extraction, time interval and change rate calculation, harmonic distortion feature description enhancement, extreme value growth rate and phase drift rate are utilized, time periods with prominent fluctuation amplitude are screened, harmonic change trend prediction precision is improved, and the harmonic change trend prediction precision is improved through zero-sequence component and phase offset calculation in combination with periodic change features. The harmonic source is accurately separated, the harmonic cause identification capability is improved, the compensation current is calculated based on the harmonic source, the injection opportunity is optimized, the compensation parameter is adjusted before the harmonic peak value, and the compensation response speed and the matching precision are improved.

The invention relates to the technical field of electrical detection, in particular to an electricity meter load monitoring method and system based on an electric energy quality analyzer, and the method comprises the following steps: extracting three-phase voltage phase deviation characteristics in a disturbance period, combining with the comparison of a frequency band change trend and fundamental frequency power, recognizing an interference coupling section, and analyzing a jump frequency point; and outputting an ammeter load monitoring result. According to the method, the phase deviation angle of the three-phase voltage is extracted in the voltage disturbance period, and the cross-phase synchronization index is constructed, so that the synchronous response characteristics of different loads to disturbance can be accurately revealed, and the accuracy of load response attribution judgment is enhanced. On the basis of cross-phase synchronous analysis, a corresponding relation between frequency band characteristics and response attribution is constructed, so that load response subdivision has a phase difference identification capability and a frequency behavior calibration capability, and the discrimination robustness under a multi-source interference background is improved.

The invention relates to the technical field of inverter control, and discloses an inverter output power control method and device, equipment and a storage medium. The method comprises the following steps: performing power frequency fundamental wave extraction and multi-band band-pass filtering on acquired voltage and current sampling data; performing phase compensation, first coordinate transformation and positive and negative sequence decoupling operation on the filtered fundamental wave principal component data; on the basis of a synchronous phase angle and a power grid fundamental wave frequency obtained by positive and negative sequence decoupling operation, carrying out second coordinate transformation, moving average and harmonic power delay difference operation on three-phase current and voltage data of an alpha-beta coordinate system; performing multi-level power calculation, power capacity distribution, error characteristic evaluation and decoupling operation on the inversion fundamental component and the inversion harmonic component subjected to the difference operation; and performing output signal modulation on the inversion power control quantity of the decoupling operation based on the fundamental wave synchronization phase angle, and generating a power control result. According to the invention, the control performance of the inverter on the output power in actual operation is improved.

The invention relates to the technical field of electrical performance testing, in particular to a water supply equipment electrical performance detection system based on artificial intelligence, which comprises an electrical parameter acquisition module, an energy efficiency analysis module, an insulation performance evaluation module and a comprehensive diagnosis module. According to the invention, a three-phase voltage and current root-mean-square value is dynamically calculated through a broadband current transformer and a sliding window integration method, a 50Hz fundamental component amplitude is extracted to separate power frequency and high frequency harmonic waves, a continuous period energy efficiency ratio standard deviation triggers an insulation detection threshold value, and a parameter fluctuation and insulation degradation response mechanism is established. Harmonic interference correction synchronous processing energy efficiency ratio and leakage current integration, the detection error being lower than 5%, temperature rise rate linear regression and bearing current threshold value cooperative determination, winding aging cross validation, fault misjudgment rate reduction to 26%, closed-loop detection fusion transient capture, dynamic threshold value triggering and multi-parameter diagnosis, early warning success rate reaching 92%, and positioning response being reduced to 3 seconds.

The invention discloses a power distribution network three-core cable fault distance measurement analysis method and system, and relates to the technical field of fault distance measurement, and the key points of the technical scheme are that the method comprises the steps: carrying out the empirical mode decomposition of three-phase voltage and current signals; generating a dynamic correction wave velocity based on the cable type, the environment temperature and the soil humidity parameter; determining the first arrival time of the wave head of the initial traveling wave according to the instantaneous frequency abrupt change point of the alpha-mode component, screening the second arrival time of the first reflected wave by using the amplitude gradient of the zero-mode component, and calculating the arrival time difference; and calculating an initial fault distance, and calling the impedance matrix to iteratively correct the initial fault distance. According to the method, the dynamic wave velocity is coupled with multiple factors, the limitation of single parameter correction is broken through, and the problem of transient drift of the wave velocity is solved; and the STFT high-frequency resolution and the wavelet low-frequency stability are fused, and the ridge continuity is optimized in combination with dynamic programming, so that the traveling wave head detection precision can be improved.

The invention discloses a method for predicting and suppressing harmonic waves generated by photovoltaic grid connection, which relates to the technical field of harmonic wave prediction, and comprises the following steps: detecting a three-phase current signal of a photovoltaic grid connection circuit by using an ip-iq detection method, and decomposing the three-phase current into an active component and a reactive component through Clarke conversion and Park conversion; according to the method, high-precision detection and separation of harmonic waves in the photovoltaic grid-connected system are realized by combining an ip-iq method with Clarke and Park transformation, dynamic modeling and harmonic signal prediction are performed by using the LSTM model, the defect of poor adaptability of a traditional method to nonlinear loads is overcome, and the prediction error is as low as 0.1%. Through combination of LSTM prediction and APF dynamic compensation, the compensation current opposite to the harmonic current is generated in real time, the harmonic suppression efficiency and the power grid stability are significantly improved, the electric energy quality is optimized, and the dynamic change of a complex load is adapted.

The invention discloses a calibrating device. The calibrating device comprises a base and a plurality of calibrating columns, in the first verification state, the verification columns jointly form a first verification group, a second verification group and a third verification group which are arranged in the second direction. When the first verification state is switched to the second verification state, the verification columns are rearranged into a fourth verification group and a fifth verification group, and a part of the verification columns in the second verification group can move towards the first verification group so as to form a new fourth verification group together with the first verification group; and the other part of the other verification columns in the second verification group can also move towards the third verification group so as to form a new fifth verification group together with the third verification group. The number of the verification columns of the fourth verification group and the fifth verification group is equal to the number of the verification columns of the first verification group, the second verification group and the third verification group. According to the invention, the verification column moves on the base and is compatible with equipment such as a single-phase electric energy meter and a three-phase electric energy meter at the same time, the verification column is reused, and the material cost is low.

The embodiment of the invention discloses a midpoint potential control method based on a diode clamping type three-level grid-connected inverter and a related device. The method comprises the following steps: generating an initial three-phase modulation wave through a current loop closed-loop control method according to a collected three-phase current value and a three-phase voltage value of a power grid side of the diode-clamped three-level grid-connected inverter; according to an initial modulation waveform generated by the initial three-phase modulation wave, a three-phase current value and an acquired voltage value of a voltage dividing capacitor at the direct current side of the diode clamping type three-level grid-connected inverter, calculating a zero-sequence component required by neutral-point potential balance; superposing a zero-sequence component required by neutral-point potential balance with the initial modulation waveform to obtain a final modulation wave; and generating a driving signal matched with each phase of bridge arm in the diode clamping type three-level grid-connected inverter according to the final modulation wave. By adopting the invention, the neutral-point voltage can be balanced, the distortion of the output waveform at the alternating current side is reduced, the voltage stress of the device is reduced, and the service life of the power device is prolonged.

The invention discloses an alternating current charging pile ordered charging power regulation and control method, and relates to the technical field of alternating current charging pile charging power regulation and control, and the method specifically comprises the following steps: obtaining the operation state information of each alternating current charging pile in real time, and generating a voltage fluctuation influence index and a load dynamic response index of each alternating current charging pile; constructing a power influence evaluation model for the generated voltage fluctuation influence index and the load dynamic response index of each alternating current charging pile, generating a power influence evaluation coefficient of each alternating current charging pile, performing analysis after generation, and evaluating the influence degree of the three-phase voltage phase difference fluctuation on the charging power of each alternating current charging pile. And the alternating current charging piles are divided into low-influence charging piles, medium-influence charging piles and high-influence charging piles according to the evaluation result. According to the method, the problem that the charging power is influenced by three-phase voltage phase difference fluctuation is solved, and the efficient and stable effects of dynamic evaluation and accurate regulation and control of the power of the charging pile are achieved.

The invention discloses a multi-end line pilot protection method and system based on time domain model identification, and relates to the technical field of electrical engineering, and the method comprises the steps: obtaining a three-phase voltage sampling value, a three-phase current sampling value and a switching value of each end of a multi-end line; judging whether each end of the multi-end line meets a protection starting condition or not; if yes, differential voltage variation and differential current are calculated, and correlation coefficients of the differential voltage variation and the differential current are calculated; judging whether the correlation coefficient is within a preset fault threshold range or not; if the correlation coefficient is not within the preset fault threshold range, determining that the multi-terminal line has an external fault, and enabling the protection device not to act; and if the correlation coefficient is within a preset fault threshold range, determining that the multi-terminal line has an internal fault, and enabling the protection device to act to remove the fault. According to the invention, the influence of capacitive current and a power electronic power supply on pilot protection performance is overcome, the operating characteristics of a relay protection device are improved, and safe and stable operation of a power system is ensured.

The invention discloses an electric energy metering method under power grid waveform distortion, and particularly relates to the technical field of electric energy metering. The problems of false triggering of an energy compensation mechanism, metering deviation and electricity price settlement risks caused by zero-sequence current or false phase drift easily generated in a multipoint grounding or grounding fault power system in the prior art are solved. According to the anomaly identification and control method integrating zero-sequence current frequency domain characteristic analysis and three-phase phase deviation trend consistency judgment, the false phase deviation state is accurately identified through synchronous sampling, frequency domain analysis and trend consistency evaluation of three-phase voltage, three-phase current and neutral line current, and the false phase deviation state is accurately identified. The error compensation behavior is shielded in real time, the fundamental wave power metering mode is switched to, the electric energy metering accuracy is guaranteed through an error backtracking correction mechanism after recovery, and the anti-interference capability and metering reliability of the electric meter under complex working conditions are effectively improved.

Embodiments of this invention discloses a split-phase output power adjustment system, adjustment method, and storage medium in a low voltage transformer area. The system includes adjustment power supplies, split-phase power adjustment modules, sub-controllers, a main controller. The adjustment power supplies connected to the split-phase power adjustment modules, and total power P of the adjustment power supplies complying with a relationship as follows: P=Pt=PG1+PG2+ . . . . PGn; wherein Pt is power required to comply with three-phase current unbalance adjustment of a distribution transformer, PG1, PG2, . . . PGn is power generated by each of the adjustment power supplies to compensate three-phase current unbalance in a transformer area; wherein the split-phase power adjustment modules are connected to lines of three phases A, B, and C and a neutral line N in the transformer area; wherein the sub-controllers are connected to the adjustment power supplies, and the sub-controllers communicate with the main controller to control power generated by each of the adjustment power supplies, so as to compensate the unbalanced three-phase current in the transformer area. Coordinated adjustment of multiple distributed power supplies realizes precise control of three-phase imbalance in the transformer area, which reduces line loss and improves power quality.

The invention provides an electric energy quality device power smooth flexible capacity expansion method for a new energy access scene. The method comprises the following steps: acquiring three-phase voltage, current and power signals, obtaining standardized three-dimensional tensor data through multi-dimensional tensor spectrum projection decomposition, calculating a characteristic value and a characteristic tensor base, and generating a dynamic characteristic vector and a weight coefficient set; a multi-layer probability graph matrix is constructed, a feature mapping matrix and a hierarchical contribution coefficient are obtained through iterative calculation, a fluctuation feature tensor is constructed, and a multi-time scale prediction model is established; constructing a control manifold space and a measurement tensor, calculating a topological connection matrix, designing a multi-dimensional control law and performing stability optimization; and constructing an embedded feature matrix and an inter-module distance matrix, calculating a capacity expansion weight and a power distribution scheme, and performing spectral domain equalization control and grid-connected coordination control. According to the invention, the power smoothing effect is obviously improved, and the system capacity expansion flexibility is enhanced.

The invention relates to the technical field of industrial metallurgy, in particular to a submerged arc furnace operation control system which comprises a transformer controller, an electrode control unit, a feeding unit, a detection unit and a data analysis unit. The transformer controller is used for adjusting the gear of the secondary voltage; the electrode control unit is used for controlling pressing, releasing and lifting of the electrode; the charging unit is used for adding mineral aggregate into the submerged arc furnace; the detection unit is used for detecting the material level height of mineral aggregate in the furnace, the weight of a trough, the electrode height, the electrode thickness and the electrode temperature; the data analysis unit is used for adjusting the height difference value of the three-phase electrode; the electrode consumption degree is judged, and the electrode pressure release period and the depth of the electrode inserted into the mineral aggregate in the furnace are adjusted; and drawing a temperature change curve, judging the volatility of the electrode current, and adjusting the secondary voltage gear and the height of the electrode. The height of the three-phase electrode is adjusted according to the consumption degree of the electrode and the volatility of the electrode current, so that the stability and the operation efficiency of the submerged arc furnace are improved.

The invention relates to the technical field of three-phase current data processing, in particular to an electric energy quality intelligent monitoring method and system for a four-fusion integrated terminal. The method comprises the following steps: acquiring a current sequence and a monitoring phase corresponding to each phase line; calculating the suspected abnormal degree of the current monitoring point in the current sequence of the monitoring phase, and judging whether the current monitoring point is an abnormal monitoring point or not; if the current monitoring point is an abnormal monitoring point, acquiring a continuation curve; calculating a continuation distribution characteristic value of the abnormal monitoring point according to each data point in the continuation curve; correcting the continuation distribution characteristic value based on the distance between trough points of the crest of the continuation curve and the height of the crest to obtain a corrected continuation distribution characteristic value; obtaining the current abnormal degree of the abnormal monitoring point based on the suspected abnormal degree of the abnormal monitoring point and the corrected continued distribution characteristic value; and judging whether the electric energy quality is abnormal according to the current abnormal degree. According to the invention, the electric energy quality of the four-fusible integrated terminal can be accurately monitored.

The invention belongs to the technical field of circuit monitoring, and particularly relates to an AI fault identification method and system for an electric power circuit, and the method comprises the steps: constructing a cross-modal data flow with a space-time mark through the synchronous collection of a thermal imaging sequence and a three-phase current waveform, extracting the characteristics of a multi-physical field through combining the characteristics of a wire material, and carrying out the recognition of an AI fault. And establishing a thermal-electric coupling relationship by using space-time alignment convolution, further analyzing and calculating correlation strength between temperature anomaly and current fluctuation through a sliding window, constructing a dynamic threshold model, generating a fault probability thermodynamic diagram, and finally outputting a graded early warning signal. Compared with the prior art, the method has the advantages that deep fusion analysis of thermal imaging and electrical signals is realized, the recognition precision and response speed of potential fault points are improved, the abnormal state of the wire joint can be found and accurately positioned earlier, the misjudgment rate is effectively reduced, and the safety and stability of power grid operation are improved.

The invention relates to the technical field of simulation testing, in particular to a motor simulator and a testing system. The motor simulator comprises a sampling module, a communication interface, a first processing module and a load module. The input end of the load module receives three-phase voltage and three-phase current input by the MCU module, and the output end of the sampling module is connected with the input end of the first processing module through a communication interface; the sampling module collects the three-phase voltage output by the output end of the MCU to obtain a three-phase voltage signal, and transmits the three-phase voltage signal to the first processing module through the communication interface; the first processing module is configured with a motor model, and the first processing module is configured to process the three-phase voltage signal based on the motor model to obtain an output signal and output the output signal to the upper computer and the MCU module; the motor model represents the corresponding relation between the input voltage of the motor and the output signal of the motor. By adopting the method, the MCU module can be tested in the absence of a real motor.

The invention relates to a tiny fault detection method for a rotary transformer of a vehicle driving motor. The method comprises the following steps: acquiring a three-phase current measured value of a motor, a rotating speed measured value of a motor rotor and a position angle measured value; converting the three-phase current measured value of the motor into a fixed coordinate system through coordinates to obtain a two-phase current measured value; obtaining a two-phase current estimated value, a rotating speed estimated value of the motor rotor and a position angle estimated value output by the fault detection observer, comparing the two-phase current estimated value, the rotating speed estimated value of the motor rotor and the position angle estimated value with the two-phase current measured value, the rotating speed measured value of the motor rotor and the position angle measured value, and calculating to obtain an evaluation function value; whether the evaluation function value exceeds a pre-configured threshold value or not is judged, and if yes, it is judged that the rotary transformer has a fault. Compared with the prior art, the method has the advantages that the influence of the fault can be distinguished from the uncertainty and noise of the system, so that the detection precision is improved.

The invention relates to a multi-branch power distribution network double-end traveling wave fault positioning method and system, and the method comprises the steps: deploying a plurality of measurement points based on the head and tail ends of a radial power distribution network and branch terminals, collecting topological information, and calculating the linear mode wave velocity; using the three-phase voltage data after the fault to extract traveling wave line mode and zero mode components through modulus decoupling; a line mode component with the strongest global mutation is selected as a reference, and a wave head time sequence table is generated through wavelet decomposition and mutation detection; and correcting the zero-mode wave velocity by combining the topology, the time sequence table and the line-mode wave velocity, and determining a fault interval and outputting a fault position after compensation and correction by using the line-mode and zero-mode wave head time difference. According to the invention, through a wave head time sequence analysis and time difference compensation mechanism based on cooperation of multiple measuring points, positioning errors caused by clock asynchronization and parameter disturbance are effectively overcome, accurate distance measurement which is not influenced by clock errors is realized, and the distance measurement precision is significantly improved; and meanwhile, the point distribution requirement is simplified, accurate judgment and positioning of a fault interval can be realized only by a branch single measuring point, and high economy and deployment flexibility are both achieved.

The invention relates to the technical field of crane line fault diagnosis, in particular to a crane line fault diagnosis system and method based on multi-source data fusion, which comprises a data acquisition and processing unit, a mechanical and electrical coupling characteristic unit and a characteristic fusion and fault quantification unit, the three-axis vibration acceleration and the three-phase current waveform of the track are obtained through the data collecting and processing unit, the mechanical and electrical coupling characteristic unit conducts three-dimensional vector synthesis and wavelet packet decomposition on vibration data, and a time-space incidence matrix of harmonic distortion and vibration is constructed. And the feature fusion and fault quantification unit outputs coupling factors by using a bidirectional long-short-term memory network and an attention mechanism, and outputs a fault probability value through a dynamic time warping matching algorithm after time-frequency domain analysis and sample entropy judgment, so that time-space correlation modeling and dynamic fault matching of multi-source data are realized. And the fault positioning precision and the diagnosis accuracy are improved.

The invention provides a control method and device for a network-forming type energy storage converter, and belongs to the field of energy storage converter control. The method comprises the following steps: acquiring three-phase current and three-phase voltage of a grid-connected point of a target network-building type energy storage converter; according to the three-phase current and the three-phase voltage, determining active output power, reactive output power, and resistance and reactance of a power grid to which the target network-forming type energy storage converter belongs; based on the resistance and the reactance, outer ring self-adaptive parameters are calculated; wherein the outer ring adaptive parameter is used for performing VSG control; and according to the outer-loop adaptive parameter, the three-phase current, the three-phase voltage, the active output power and the reactive output power, controlling the target network-forming type energy storage converter. According to the invention, the active control strategy and the reactive control strategy in VSG control are improved based on the outer-loop adaptive parameters, so that the problem of coupling between the damping coefficient and the primary frequency modulation coefficient is solved, and the situation that the control performance is reduced and unstable due to the change of the impedance of the power grid is avoided.