Abstract: The disclosure proposes a yaw calibration method and system for a wind turbine. The calibration method includes: establishing a cylindrical coordinate graph of wind resource distribution based on historical wind farm operation data, to determine a wind direction interval of main inflow wind conditions of a wind farm; calculating an effective value of active power of each wind speed sub-interval, and obtaining a fitted power curve of each refined interval through curve fitting; and setting an angle between a central axis of a refined interval for a fitted power curve corresponding to a calibration curve in each wind speed range and a central axis of the to-be-calibrated wind direction interval as a yaw error calibration value in the wind speed range, to establish a wind speed-yaw error calibration value lookup table; and determining a yaw error calibration value under a current wind direction and a current wind.

Abstract: The present application relates to a method for evaluating an operation of a distribution network based on data capture and Spark. The method includes: acquiring a packet from a terminal, and mirroring the packet through a mirroring port of a switch to acquire a mirror packet of the packet; analyzing the mirror packet, acquiring a 101/104 protocol packet, and storing the 101/104 protocol packet into an HDFS; acquiring the 101/104 protocol packet from the HDFS, parsing the 101/104 protocol packet on a Spark platform to acquire a parameter in the 101/104 protocol packet, and analyzing and processing the parameter to obtain a key indicator for evaluating the operation of the distribution network; and displaying the key indicator through a web page.

Abstract: Provided are a ground fault protection method and apparatus for a photovoltaic station output transmission line. A circuit breaker on a photovoltaic side is controlled by a control element. Whether measured zero sequence impedance on the photovoltaic side of a segment line has a large variation before and after an action of power grid side distance protection is determined, the variation of the measured zero sequence impedance is inputted into the control element, in condition that the variation of the measured zero sequence impedance is less than a setting value, a tripping signal is outputted to the circuit breaker on the photovoltaic side to isolate the fault; and in condition that the variation of the measured zero sequence impedance is greater than the setting value, photovoltaic side distance protection is not started.

Abstract: A flexible coordinated control method adapted to a thermal power unit in a deep peak-regulating operation includes: adding a reverse compensation channel from a fuel quantity instruction to a power generation load instruction on a basis of a traditional coordinated control system of a boiler-following mode; meanwhile, constructing a flexible factor by using a main steam flow quantity signal, and correcting a gain of the reverse compensation channel by the flexible factor in a product mode to obtain a reverse power generation load instruction bias value; and correcting the power generation load instruction of the unit by using the reverse power generation load instruction bias value, so as to give priority to guaranteeing the control quality of a power generation load and a throttle pressure before a steam turbine under conventional load conditions and give priority to guaranteeing the combustion stability under deep peak-regulating conditions.

Abstract: A flexible coordinated control method adapted to a thermal power unit in a deep peak-regulating operation includes: adding a reverse compensation channel from a fuel quantity instruction to a power generation load instruction on a basis of a traditional coordinated control system of a boiler-following mode; meanwhile, constructing a flexible factor by using a main steam flow quantity signal, and correcting a gain of the reverse compensation channel by the flexible factor in a product mode to obtain a reverse power generation load instruction bias value; and correcting the power generation load instruction of the unit by using the reverse power generation load instruction bias value, so as to give priority to guaranteeing the control quality of a power generation load and a throttle pressure before a steam turbine under conventional load conditions and give priority to guaranteeing the combustion stability under deep peak-regulating conditions.

Abstract: A resampling method based on window function for flexible sampling rate conversion in broadband frequency measurement devices is described. The resampling algorithm can satisfy the requirements of different sampling rates. The frequency responses of the filter in the resampling model based on the Farrow structure are analyzed, and the design criterion of the filter in resampling model is considered. A fractional delay filter design model based on window function method is described. A fractional delay filter matrix, which is expressed by polynomial form, is constructed. Then the expression related to subfilter coefficients is obtained and subfilter coefficients are solved for by the least square method.

Abstract: A coal-fired power generation system and a supercritical CO2 cycle system thereof are provided. The supercritical CO2 cycle system includes a compressor unit and a turbine unit. The turbine unit includes a preceding stage heater, a preceding stage turbine, a last stage heater and a last stage turbine successively connected in series. An exhaust port of at least one of compressors in the compressor unit is in communication with the turbine unit through a split flow pipe, and a communication position between the split flow pipe and the turbine unit is located downstream of a suction port of the preceding stage turbine. An auxiliary regenerator and an auxiliary heater are provided at the split flow pipe, and the auxiliary regenerator is located upstream of the auxiliary heater.

Abstract: The present disclosure provides a method for preparing a perovskite quantum dot film by one-step crystallization, and belongs to the field of perovskite quantum dot material technology. The present disclosure uses adamantanemethylamine and hydrohalic acid as ligands, first mixes a cesium halide, a lead halide, and the ligands with a solvent to obtain a precursor solution, then deposits the precursor solution on a substrate, and then heats the substrate to obtain the CsPbX3 perovskite quantum dot film. The present disclosure uses adamantanemethylamine and hydrohalic acid as the ligands, which can quickly coat the perovskite, complex with the CsPbX3 perovskite, and directly form the perovskite quantum dot via a strong steric effect. Further, the present disclosure is simple and inexpensive, can directly obtain a high-quality perovskite quantum dot film with a thickness of more than 500 nm by one-step crystallization.

Abstract: The disclosure discloses a commutation failure prediction method, device and storage medium based on energy accumulation features of inverter. The method includes the following steps: collecting instantaneous values of three-phase valve side current and calculating the derivatives of the three-phase valve side current according to the instantaneous values of three-phase valve side current; the derivative includes positive, negative and zero states; according to the derivatives of the three-phase valve side current, determining the locations of incoming valve and ongoing valve; based on the valve side current of the incoming valve and ongoing valve, calculating energy accumulation features of the 12-pulse inverter; predicting whether the commutation failure from the incoming valve to the ongoing valve will happen according to the states of the derivatives of the three-phase valve side current and the energy accumulation features of the 12-pulse inverter.

Abstract: A synchrophasor measurement-based disturbance identification method is described considering different penetration levels of renewable energy. A differential Teager-Kaiser energy operator (dTKEO)-based algorithm is first utilized to improve multiple-disturbances detection accuracy. Then, feature extractions via the integrated additive angular margin (AAM) loss and the long short-term memory (LSTM) network is described. This enables one to deal with intra-class similarity and inter-class variance of disturbances when high penetration renewable energy occurs. With the extracted features, a multi-stage weighted summing (MSWS) loss-based criterion is described for adaptive data window determination and fast disturbance pre-classification. Finally, the re-identification model based on feature similarity is established to identify unknown disturbances, a challenge for existing machine learning algorithms.

Abstract: The present application proposes a method of locating oscillation sources of wind power integrated system based on energy spectrums. The method include: collecting information of voltage and current at the terminal of each generator and obtaining a dynamic energy curve of each generator over time; choosing the generators whose curve shows an upward trend in the dynamic energy over time curve into alternative generators; obtaining and processing energy spectrums of synchronous generator, DFIG with PLL, and/or an analogical energy spectrum of DFIG with virtual inertia among the alternative generators; selecting generator with maximum proportion of dominant oscillation mode as an oscillation source reference generator; and calculating the similarity coefficients between energy spectrums of each remaining candidate generator and the oscillation source reference generator, determining the oscillation source generators.

Abstract: A power margin tracking control method and system for a multi-terminal high-voltage direct current converter station are provided. A power adjustment factor is introduced on the basis of a droop coefficient, to realize a self-adaptive regulation of a converter station operation mode to a real-time fluctuation of a wind and solar power. In this way, the system operation stability and the power fluctuation allocation capability in a grid-connected system are improved. Furthermore, a DC voltage deviation in the multi-terminal high-voltage direct current grid is reduced.

Abstract: A data-driven PMU bad data detection algorithm based on spectral clustering using single PMU data is described. The described algorithm does not require the system topology and parameters. First, a data identification method based on a decision tree is described to distinguish event data and bad data by using the slope feature of each set of data. Then, a bad data detection method based on spectral clustering is described. By analyzing the weighted relationships among all the data, this method can detect the bad data that has a small deviation.

Abstract: A method for quantum key fusion-based virtual power plant security communication includes: identity authentication, performing identity authentication between a client and a server in a virtual power plant based on a communication requirement to acquire a root key; key distribution: generating a key encryption key and a message authentication key based on the acquired root key and performing negotiation on a data encryption key to obtain the data encryption key; and data encryption: encrypting to-be-encrypted data using the data encryption key, and implementing communication of the data. During the identity authentication or the key distribution, negotiation on a quantum key is performed by a quantum key server, and the quantum key obtained by the negotiation is used for implementing the identity authentication or used as the data encryption key. A device for quantum key fusion-based virtual power plant security communication and a computer storage medium are provided.

Abstract: The disclosure relates to a method, system and storage medium for suppressing sub/super-synchronous oscillation for direct-drive wind turbine based on energy compensation.

Abstract: The disclosure relates to an active damping control method and system for sub-synchronous oscillation of DFIG, and storage medium. The method comprises the following steps: collecting oscillation components of stator current and/or stator voltage; determining each energy branch in DFIG converter according to the flow path of the oscillation component(s) of the stator current and/or the stator voltage in DFIG converter; determining the corresponding function of each energy branch according to oscillation component(s) the stator current and/or the stator voltage; determining the energy compensation branch and its corresponding energy compensation function in DFIG converter according to the corresponding function of each energy branch and converter parameters; controlling the sub-synchronous oscillation of DFIG by controlling the energy compensation branch according to the energy compensation function.

Abstract: The disclosure relates to a method and system for evaluating the stability of HVDC receiving end system and storage medium, which relates to the technical field of high voltage direct current transmission. The method includes: collecting voltage at a generator port, current at the generator port and rotational speed of the generator after eliminating fault; determining a corresponding relationship between the generator dynamic energy and the time according to the voltage at the generator port, the current at the generator port and the rotational speed of the generator; determining the attenuation intensity of the generator dynamic energy according to the corresponding relationship between the generator dynamic energy and the time; determining stability of the HVDC receiving end system according to the attenuation intensity of the generator dynamic energy.

Abstract: The disclosure relates to a method and system for AC line distance protection in AC/DC hybrid power grid, and storage medium.

Abstract: The present disclosure is directed to a single-phase reclosing method, device and storage medium for AC/DC system. The method comprises: acquiring three-phase voltages at inverter-side AC bus close to the transformer, three-phase currents measured at the outlet of inverter-side AC line and three-phase voltages at inverter-side AC bus far from the transformer; calculating the energy calculation value and energy operation value of the fault line; identifying the fault nature of fault line within the maximum time delay, according to the energy calculation value and energy operation value of fault line and an energy criterion of transient/permanent fault; issuing a reclosing control signal based on the fault nature of fault line to realize effective reclosing of the fault line.

Abstract: The disclosure discloses a commutation failure prediction method, device and storage medium based on energy accumulation features of inverter. The method includes the following steps: collecting instantaneous values of three-phase valve side current and calculating the derivatives of the three-phase valve side current according to the instantaneous values of three-phase valve side current; the derivative includes positive, negative and zero states; according to the derivatives of the three-phase valve side current, determining the locations of incoming valve and ongoing valve; based on the valve side current of the incoming valve and ongoing valve, calculating energy accumulation features of the 12-pulse inverter; predicting whether the commutation failure from the incoming valve to the ongoing valve will happen according to the states of the derivatives of the three-phase valve side current and the energy accumulation features of the 12-pulse inverter.