Abstract: Disclosed are a fault early-warning method and a fault early-warning system applied to a gas turbine unit, and an apparatus. The method includes: calculating, by means of a mechanism model, predicted data of prediction parameters in a gas turbine unit, and performing data comparison on the predicted data and real data of the prediction parameters, so as to obtain an error matrix; constructing several Kriging primary functions according to the mechanism model; screening an optimal Kriging primary function from the several Kriging primary functions according to the error matrix, and performing error compensation on the mechanism model by using the optimal Kriging primary function; and performing fault early warning on the gas turbine unit by means of the mechanism model after error compensation. By means of the present application, the problem of a large number of fault false alarms in fault early warning of an existing gas turbine is solved.

Abstract: A method for checking a medium-term and long-term maintenance plan of a power grid. A predicted load value and one or more historical load values of a power grid are acquired and clustered through a clustering algorithm, and a historical moment at which a historical load value is in a same cluster as the predicted load value and has a largest load value is selected as a target historical moment. A power grid operation mode model at the target historical moment is acquired, and the power grid operation mode model is updated according to the maintenance plan and open loop point information by using a full wiring approach to obtain a future-state power grid operation mode model. Ground state power flow data of the power grid are calculated based on the operation mode model, and safety check is carried out according to a preset ground state power flow limit.

Abstract: A multi-timescale voltage regulation method based on source-grid-load-storage multi-terminal collaboration of a power distribution network is disclosed, which comprises: establishing, based on a Petri network, a multi-mode switching control model based on voltage security event trigger to realize effective control of a global voltage; establishing multi-objective optimization taking into account a source-storage-load regulation cost and a network transmission loss to realize collaborative and dynamic control of controllable resources of a source terminal, a load terminal and a storage terminal in each operating mode; and establishing a source-storage-load multi-terminal collaboration-based distributed voltage control model based on voltage security event trigger over a short timescale by taking into account the problems of voltage magnitude being out of limit and voltage leap, and solving online an optimal control sequence of the source terminal, the load terminal and the storage terminal in a receding horizo

Abstract: The present disclosure provides a system for perceiving an operating state of a large power transformer based on vibro-acoustic integration, including a perception layer, a network layer, and a diagnostic layer, where the perception layer is used for monitoring, in real time, a state parameter for a coupling vibration signal and an acoustic signal of each of a transformer core, a winding, a clamp and a housing, a state parameter of each of a vibration signal and an acoustic signal during a gear position change of an on-load tap changer (OLTC), and preliminarily diagnosing and analyzing monitored data. The system can monitor the operating state of the OLTC online for a long time, flexibly configure the sensor channel and the sensor type according to different application requirements, automatically acquire and identify the gear position change, and correctly identify and process a gear position corresponding to the monitoring signal.

Abstract: A method for analyzing a correlation between rail transit and direct current (DC) magnetic bias of a transformer includes the steps of, A: obtaining a current of a feed cable and a DC magnetic bias current: measuring the feed cable current in rail transit and the DC magnetic bias current of a transformer in a power grid within a certain period by a monitoring apparatus; B: calculating a characteristic quantity of the feed current within the measurement period based on the obtained current of the feed cable; C: calculating a characteristic quantity of the DC magnetic bias current within the measurement period based on the DC magnetic bias current; and D: calculating a support degree and a confidence coefficient based on the calculated characteristic quantity of the feed current and the calculated characteristic quantity of the DC magnetic bias current, and generating a correlation rule.

Abstract: The embodiments of the present invention disclose a line protection method and a related apparatus for a flexible grounding system of a power distribution network. The method comprises outputting a first compensation voltage by a voltage source of a flexible grounding device of each line of a target power distribution network in the case where a ground fault occurs in the target power distribution network; starting to calculate the zero-sequence impedance of each line in real time by the zero-sequence impedance protection device; after the first compensation voltage is output for a first output duration, outputting a second compensation voltage; calculating the zero-sequence impedance of each line in real time by the line zero-sequence impedance protection device; determining a fault line by the zero-sequence impedance protection device, and cutting off the fault line to isolate the ground fault after a trip for a preset time delay.

Abstract: Provided is a method for measuring surface characteristics of at least a portion of an object, including providing a light source; generating a first interference pattern on the at least a portion of the object; capturing an image of the first interference pattern; shifting the phase of the light source to generate a second interference pattern; capturing an image of the second interference pattern; filtering distortion from the interference patterns; extracting a wrapped phase of the at least a portion of the object based on the images; unwrapping the wrapped phase of the at least a portion of the object to generate an unwrapped phase; identifying a computed depth map distance to the at least a portion of the object; and fitting an ideal part to the computed depth map of the at least a portion of the object to measure the surface characteristics.

Abstract: Disclosed is an electrical topology of an integrated DC charging station and an operation control method. The electrical topology comprises a supply side DC bus, K discrete charging pile units and a mutual aid total DC bus; each charging pile unit comprises an input DC bus, a mutual aid sub-DC bus, an output DC bus, N isolation branches, a non-isolation DC/DC module and an output terminal, the input DC bus is connected to the supply side DC bus, and the mutual aid sub-DC bus of each charging pile unit is connected to the mutual aid total DC bus; the isolation branch comprises an output branch and a mutual aid branch; and when all the output branches of one charging pile, unit are started and the output power cannot meet the required power, the mutual aid branches of other charging pile units are started to meet the required power.

Abstract: The invention provides various designs of an apparatus and method for attemperating a gas stream temperature. The apparatus of the present invention provides a body through which a gas stream passes that permits, as desired, a second gas, such as gas outside of the gas duct or such as ambient air, to be added to the main gas stream to attemperate the temperature of the main gas stream. The body or device may be referred to as a variable eductor having a plurality of openings through which a second gas may pass into the main gas stream. The openings may be opened or closed, and the variable eductor provides control over which openings and the degree to which each opening is opened. In some designs the variable eductor is inserted between two portions of a gas duct. The variable eductor has widespread application, such as downstream of a gas turbine to attemperate the exhaust gas temperature during startup.

Abstract: The present invention discloses a unit commitment method considering security region of wind turbine generators with frequency response control, and the main steps are: 1) determining security region of wind turbine generators when provides frequency response; 2) based on the security region of the wind turbine generators when provides frequency response, establishing a unit commitment model considering security region of wind turbine generators; and 3) calculating the unit commitment model considering the security region of the wind turbine generators by using mixed-integer linear programming method, and obtaining the operation result of the unit commitment considering the security region of the wind turbine generators with frequency response control. The present invention can be widely used in the setting of frequency response parameters of wind turbine generators dispatched in the prior art and the start-stop and output plans of synchronous generator.

Abstract: A device and method for degassing an on-load tap-changer (OLTC) of a transformer for convenient on-site operation. The degassing device includes an OLTC. The OLTC is respectively connected with an oil suction pipe and an oil injection pipe. One end of the oil suction pipe extends to the inside bottom of the OLTC, and the other end of the oil suction pipe extends to the outside of the OLTC to connect with an oil suction and degassing device. One end of the oil injection pipe extends to an upper part inside the OLTC, and the other end of the oil injection pipe extends to the outside of the OLTC to connect with a vacuum oil injection device. The present disclosure has the advantages of convenient on-site operation, excellent degassing effect, simple structure and convenient installation, reduces degassing time and manpower and investment in maintenance, and improves degassing quality.

Abstract: A networked control method for primary frequency regulation of a new energy power station based on a source-grid-load-storage networked cloud decision control system platform comprises: determining, according to historical operating data of a new energy power station, primary frequency regulation predictive values of power generation units of the new energy power station; determining, according to the primary frequency regulation predictive values, optimal control sequences of inverters of the power generation units at different times based on a pre-established inverter active power model, wherein the optimal control sequences comprise multiple control quantities of active power of the inverters; marking the optimal control sequences at the different times with time scales, sending the optimal control sequences to executing devices of the power generation units, receiving the optimal control sequences, and determining whether to store or not store the optimal control sequences; and determining the control qua

Abstract: A method and a system for locating a fault of a complex power line are provided. Several monitoring points on the complex power line can be obtained by providing several traveling wave head monitoring sensors on the complex power line. The complex power line is transformed into coordinates in conjunction with an arrival moment and a location corresponding to the monitoring points, thereby establishing a trunk line fault-locating equation related to a line location, the arrival moment, and a traveling wave propagation speed, from which a first fault point can thus be derived simply and quickly. If a fault point is located on a branch line, a branch line fault-locating equation is then established to derive a second fault point. Furthermore, the first fault point and the second fault point serve as a basis for deriving a target fault point of the complex power line.

Abstract: The embodiments of the present invention disclose a method and a related device for locating a ring power network fault. The method comprises: expanding in each ring line segment with an arbitrary point as a coordinate origin in a ring power network to construct a plurality of reference coordinate systems; acquiring monitoring point coordinate information and wavehead arrival time information of each of the monitoring point positions; acquiring assumed fault point information; acquiring a traveling wave propagation speed; constructing a plurality of distributed fault location equation sets according to the monitoring point coordinate information, the wavehead arrival time information, the assumed fault point information and the traveling wave propagation speed in each of the reference coordinate systems; and determining an actual fault position according to a solution result of each of the distributed fault location equation sets and the assumed fault section.

Abstract: A method and device for timing in time-varying distance protection based on multiple lines of a tower. The method includes: collecting an instantaneous current value at a time-varying distance protection installation location in the multiple lines of the tower, and acquiring preset parameters; calculating, according to the preset parameters and a multi-line ranging model, a multi-line ranging result; calculating, according to the preset parameters, the multi-line ranging result, and an adaptive calculation model, time of a section-II distance protection action and final time of a section-III distance protection action; and determining, according to the instantaneous current value, the preset parameters, and a cross-line failure auxiliary criterion model, final time of the section-II distance protection action.

Abstract: An electrical connector apparatus that magnetically aligns electrical contacts in a suspended magnetic connector with mating electrical contacts in a vehicle magnetic connector and holds the connectors together during an electric vehicle charging process.

Abstract: A method and device for starting direct-current (DC) transmission line protection, and a storage medium. The method includes: determining whether a sudden change of a DC line current at a present moment is greater than a sum of a memory start threshold and a maximum value in sudden changes of the DC line current within a time period preceding the present moment that is multiplied by a preset proportional coefficient, the time period being a time period between a moment preceding the present moment by a first duration and a moment preceding the present moment by a second duration; and starting DC transmission line protection in response to determining that the sudden change of the DC line current at the present moment is greater than the sum.

Abstract: A method of eliminating dissimilar metal welds has been disclosed. The method includes the steps of providing a first part having a first alloy composition; providing a second part having a second alloy composition different from the first part; connecting a containment structure to the first part; pouring a powder into the containment structure such that the powder is in contact with the first part; positioning a portion of the second part in the containment structure such that the second part compresses the powder between the first and second parts; and performing hot isostatic pressing (HIP) to consolidate the powder and join the first and second parts together.

Abstract: A cable trench inspection robot. The cable trench inspection robot includes a base spreading system, and a camera lifting system disposed on the base spreading system, where the base spreading system includes a base plate, a linear action unit, a cantilever plate, a walking assembly, and a jacking assembly, and the camera lifting system includes a travel block, an imitated four-bar assembly, a support rod, and a camera assembly. Such inspection can realize a through-wall operation by using a cable trench, thereby avoiding many use problems caused by a firewall, and efficiently completing a predetermined inspection task.

Abstract: Disclosed herein is a wide-range temperature electrolyte, a preparation thereof and a lithium ion battery. The wide-range temperature electrolyte includes a glycerin segment, a diisocyanate segment and a segment containing at least two terminal hydroxyl groups and one disulfide bond, and the self-healing electrolyte has a three-dimensional cross-linked network structure. The wide-range temperature electrolyte introduces a large number of repetitive disulfide bond groups and self-complementary hydrogen bond structures into molecules of an electrolyte base material having self-complementary hydrogen bond structures, so as to form the three-dimensional cross-linked network structure. An intermolecular exchange reaction of the disulfide bonds realizes a cross-scale (molecular, micro, and macro-scale) damage sensing response of the electrolyte and a rapid self-healing of the material, and further achieves a multi-level (molecule-component-device-system) self-healing repair function.