Abstract: A line current iM(k0) of an M side of a first direct-current transmission line is collected at a moment k0. A line current iM(k0?ts) thereof is collected at k0?ts. At a moment k0, a differential value diM(k0) of a current of the side of the first direct-current transmission line is calculated according to the line current iM(k0) and the line current iM(k0?ts). It is determined whether the differential value diM(k0) of the current meets a protection enabling criteria. If so, direct-current protection for the M side of the first direct-current transmission line is enabled. A line current iM(j) of the M side of the first direct-current transmission line is collected at a moment j. A line current iM(j?ts) thereof is collected at a moment j?ts. A differential value diM(j) of the current of the M side of the first direct-current transmission line at the moment j is calculated according to the line current iM(j) and the line current iM(j?ts).

Abstract: A system for load identification in collaboration with a cloud end includes: a smart Internet of Things electricity meter module, used for matching extracted feature quantity data with a first load feature library of the smart Internet of Things electricity meter module, and determining load feature data corresponding to unmatched feature quantity data in the feature quantity data as target load feature data; a use information front-end/acquisition module, used for calling the target load feature data and transmitting the target load feature data to a main station load identification module; and a main station load identification module, used for receiving the target load feature data, performing data direction processing on the target load feature data, determining an optimal matching strategy matching the feature data to be identified, and identifying an optimal matching solution corresponding to the feature quantity data to be identified in a second load feature library.

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 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: 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: Provided an intermittent characteristic-based demand-side resource coordination control method and system. The method includes: receiving a control request, where the control request is used for requesting control of demand-side resources having an intermittent characteristic; determining a target total control quantity of demand-side resources; determining a coordination strategy of multiple demand-side resources and an action quantity of each of the multiple demand-side resources; and performing coordinated control on the multiple demand-side resources based on the target total control quantity of demand-side resources, the coordination strategy, and the action quantity of each of the multiple demand-side resources.

Abstract: A system for load identification in collaboration with a cloud end includes: a smart Internet of Things electricity meter module, used for matching extracted feature quantity data with a first load feature library of the smart Internet of Things electricity meter module, and determining load feature data corresponding to unmatched feature quantity data in the feature quantity data as target load feature data; a use information front-end/acquisition module, used for calling the target load feature data and transmitting the target load feature data to a main station load identification module; and a main station load identification module, used for receiving the target load feature data, performing data direction processing on the target load feature data, determining an optimal matching strategy matching the feature data to be identified, and identifying an optimal matching solution corresponding to the feature quantity data to be identified in a second load feature library.

Abstract: Disclosed are a direct-current transmission line protection method and system based on pure current characteristics.

Abstract: The disclosure discloses a dynamic stability analysis method and device for a linear time-periodic (LTP) system. The method includes the following steps. Calculate the Q matrix corresponding to the LTP system, and use the eigenvalue of Q matrix whose real part is positive as an instability eigenvalue. Each instability eigenvalue is subjected to the following steps. (S1) the state space model is transformed into the infinite-order harmonic state space (HSS) model, and the truncation order m of HSS model is initialized to 1. (S2) after m-th order truncation of the HSS model, its eigenvalue thereof is calculated. If the real part of the eigenvalue of HSS model is not the same as the real part of the instability eigenvalue, m is updated, and step (S2) is performed again; otherwise, modal participation factor analysis is performed to obtain the state variables that dominate the system instability.

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 adaptive dynamic planning control method and system for a large-scale energy storage station. The method comprises: setting a structure and control target parameters of an adaptive dynamic planning control system; initializing the parameters and importing an initial state of a controlled object; calculating an original wind electricity power fluctuation rate at a current moment t and smoothing the original wind electricity power according to a change rate control strategy; calculating a smoothed wind storage power fluctuation rate, a power of an energy storage system, and a state of charge (SOC) of the energy storage system; initializing and training an evaluation module and an execution module; calculating and saving a control strategy, a smoothed wind storage power fluctuation rate, an energy storage power and a (SOC) at each moment; and outputting the control strategy at each moment, the smoothed wind storage power fluctuation rate, the energy storage power and the (SOC).

Abstract: A distribution network risk identification system and method and a computer storage medium include: multi-source information data for risk identification is acquired; the multi-source information data is analyzed and processed to obtain a risk characteristic; a risk identification index is calculated on the basis of the risk characteristic, and a state of a power grid is determined according to the risk identification index; a temporal and spatial variation rule and variation trend of the risk characteristic are analyzed; a location and cause of occurrence of a risk are determined according to the temporal and spatial variation rule and variation trend of the risk characteristic; a severity of the risk is analyzed by adopting an analogue simulation manner; and the severity of the risk is assessed, and risk early warning information is issued on the basis of an assessment result.

Abstract: Provided are a method and apparatus for calculating fault resistance and a current-limiting current of a superconducting fault current limiter.

Abstract: A standard conformance testing system and method for a CIM/E model of a power system and a storage medium include: converting the standards “Power Grid Common Model Description Specification (GB/T 30149)” and “Power Grid Operating Model Data Exchange Specification (DL/T 1380)” into practically operable testing rules, and performing automatic generation and verification of a CIM/E standard model and defect model. The testing system and method can improve the comprehensiveness and standardization of a CIM/E model standard compliance test, improving testing efficiency, promoting the level of standardization according to the CIM/E model in a power system software development process, and real time data exchange and interoperation between respective application systems, effectively supporting the safe and stable operation of a power grid.

Abstract: Provided are a method and apparatus for evaluating a degree of frequency regulation urgency of a generator set, a power system and a storage medium.

Abstract: Provided are a fire extinguishing method and a fire extinguishing system for a lithium ion battery, an electronic device and a storage medium. The method includes: real-timely collecting environmental parameter values in a battery box where a lithium ion batteries are placed; determining a safety level of the lithium ion battery according to the environmental parameter values and a preset threshold of each environmental parameter, and sending a fire extinguishing command to a fire extinguishing device according to a preset fire extinguishing control program, where the fire extinguishing control program is a fire extinguishing strategy corresponding to the safety level of the lithium ion battery; and enabling the fire extinguishing device to execute a fire extinguishing operation according to the fire extinguishing command.

Abstract: A method for identifying a pattern of a load cycle includes: performing statistics on a daily load of a system based on smart meter data; generating a curve of the daily load of the system according to the statistics on the daily load of the system; acquiring a result of clustering curves of loads of typical days by applying shape-based time sequence clustering analysis using the curve of the daily load of the system; and identifying a pattern of a load cycle according to the result of clustering the curves of the loads of the typical days.

Abstract: A current differential protection method for a self-adaptive half-wavelength line based on a time-difference method. Since an electrical distance of half-wavelength power transmission is long, after a fault occurs, there is an obvious time difference between the actuation times for protecting starting elements at two sides of a line. According to the principles of wave propagation, the position of a fault point can be determined by means of a difference between the actuation times for protecting the starting elements at the two sides of the line. By means of taking the fault point as a differential point, a current value at the differential point can be obtained according to a long line equation by means of the voltage and current at protection-mounted positions at the two sides of the line, and a differential current is then calculated.

Abstract: A digital simulation system of a power distribution network, comprising: a client and a server end. The server end is a simulation server cluster composed of several simulation servers; the simulation server cluster and the client are mutually connected through a communication bus, wherein the client is configured to use a DCOM component to invoke a simulation service provided by the server end, and the server end is configured to distribute a task to be processed to each cluster node. Constructing the above-mentioned digital simulation system facilitates an optimal planning and operation of a smart power distribution network, thereby improving the utilization efficiency and reliability of the smart power distribution network and reducing the loss of a power outage.

Abstract: An active power distribution network multi-time scale coordinated optimization scheduling method and storage medium are provided. The method includes the following steps: performing long-time scale optimization scheduling of an active power distribution network; performing short-time scale rolling optimization scheduling on the basis of MPC of the active power distribution network according to an optimization result of the long-time scale optimization scheduling of the active power distribution network. By using a model prediction control method, taking the long-time scale optimization scheduling result as a reference, and performing short-time scale rolling correction, the optimization scheduling of the active power distribution network is achieved, thereby reducing unfavorable influences of prediction precision of a distributed power supply and a low-voltage load on the optimization scheduling.