Abstract: A method for dynamically simulating the thermal response of a building by integrating the ratio of convection heat to radiation heat of heating terminals is provided, and belongs to the technical field of building environments and heating, ventilation, and air conditioning (HVAC) systems. A room thermophysical model of a building to be simulated is constructed. The ratio of radiation heat at the heating terminal is used as a variable in the room heat balance matrix equation, which shows that different heating terminals have different thermal characteristics due to different ratios of convection heat to radiation heat. The room heat balance matrix equation is solved to obtain a room air temperature equation. By integrating a heating-terminal thermal characteristic equation with the room air temperature equation, thermal characteristics of the heating terminals are combined with thermal characteristics of the building, which improves accuracy of dynamic simulation on a heating system.

Abstract: The invention relates to a fault transient features optimization method and system of AC/DC system based on dissipated energy, which belongs to the HVDC transmission technology and is used to solve the problem that the DC pulsed current is too high and the generator power angle swing of the AC system on the rectifier side is too large during the process of the HVDC transmission system restart on fault.

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 method and system for detecting a typical object of a transmission line based on UAV federated learning. The method includes: determining a detection model for a typical object of a transmission line by YOLOv3 object detection algorithm according to a prior database for the typical object; dividing a UAV network into multiple federated learning units; acquiring pictures, taken by the UAV network, of the typical object and tags corresponding to each picture to determine a training database; training, based on Horovod framework and FATE federated learning framework, each federated learning unit according to the training database and the detection model for the typical object, and determining the trained UAV network according to the trained federated learning unit; and determining, by the trained UAV network, the typical object in each picture. A congestion of communication links is avoided, thereby improving detection efficiency.

Abstract: An optimal dispatching method and system for a wind power generation and energy storage combined system are provided. Uncertainty of a wind turbine output is characterized based on spatio-temporal coupling of the wind turbine output and an interval uncertainty set. Compared with a traditional symmetric interval uncertainty set, the uncertainty set that considers spatio-temporal effects effectively excludes some extreme scenarios with a very small probability of occurrence and reduces conservativeness of a model. A two-stage robust optimal dispatching model for the wind power generation and energy storage combined system is constructed, and a linearization technology and a nested column-and-constraint generation (C&CG) strategy are used to efficiently solve the model.

Abstract: A method and a system for dispatching an independent energy storage power station is provided.

Abstract: The application involves a stability evaluation method and system of direct-drive wind turbine generator, which belongs to the technical field of wind power generation. It solves the problems of poor stability of direct-drive wind turbine generator, low safety performance, failure to realize mutual cooperation between online stability evaluation and parameter adjustment in the existing technology. Firstly, the variation of direct-drive wind turbine generator terminal voltage, current, power and PLL angle of direct-drive wind turbine generator is measured, the terminal energy and the energy negative gradient of direct-drive wind turbine generator is calculated. Then, the system stability is assessed according to the value of energy negative gradient, the influence of the critical parameters on system stability is analyzed and the preliminary adjustment strategy is proposed.

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 present disclosure relates to a method and a system of quantitative intravascular optical coherence tomography.

Abstract: The present disclosure relates to a coaxial lead structure and method for radiating a GIS partial discharge UHF signal outward. The structure includes a GIS cavity, a circular hole provided on the GIS cavity, a medium cylinder provided at the circular hole and sealing the circular hole, a thin cylindrical metal lead that extends into and is fixed to the medium cylinder, and a ground lead connected to the thin cylindrical metal lead. According to the present disclosure, a relatively strong signal may be obtained outside a coaxial lead structure, and detection of a partial discharge UHF signal at this position may increase the detection sensitivity by one time compared with the detection methods of built-in and external disc insulators.

Abstract: A post insulator includes an insulating post including a first end and a second end that are opposite to each other, a high-voltage-end grading ring connected to the first end of the insulating post, the high-voltage-end grading ring being insulated from the insulating post, a grounding-end grading ring connected to the second end of the insulating post, the grounding-end grading ring being insulated from the insulating post, and a charge control ring disposed on an outer surface of the insulating post, the charge control ring being insulated from the insulating post, and the charge control ring being configured to accumulate surface charges.

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: 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: 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 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.