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Review of Key Technologies in New Power System Based on Artificial Intelligence Empowerment DUAN Junfeng, LI Chenkun, YAO Wenxuan, GUO Siyuan Hunan Electric Power    2024, 44 (1): 1-10.   DOI: 10.3969/j.issn.1008-0198.2024.01.001 Abstract （1282）      PDF（pc） （5512KB）（1197）       Knowledge map    Save Based on the important role of artificial intelligence technology in promoting the intelligence of new power systems, this paper summarizes the current application status, technical challenges, and future development directions of artificial intelligence in new power systems. Firstly,the paper introduce the characteristics and requirements of the new power system. Then, the paper discusses the key application areas of artificial intelligence in new power systems, including the security, stability and control of large power grids, integrated collaborative analysis of source network, load storage, intelligent operation, inspection and management of power systems, as well as active distribution networks and microgrids. Finally, the paper analyzes the technical challenges faced by artificial intelligence in the new power system and proposes relevant suggestions. Reference | Related Articles | Metrics

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Numerical Simulation Study on Combustion Characteristics for 600 MW Supercritical Front and Rear Hedge Boiler QIN Yue, LI Debo, QIN Wu, KAN Weimin, YU Fengjian, JIN Fengchu Hunan Electric Power    2024, 44 (6): 46-54.   DOI: 10.3969/j.issn.1008-0198.2024.06.007 Abstract （1237）      PDF（pc） （8625KB）（57）       Knowledge map    Save In order to study the heat transfer characteristics of swirl burners under different air volume ratios, a 600 MW supercritical front and rear hedgeboiler in a power plant is simulated and calculated based on CFD technology, so as to obtain the cold state power field,hot state temperature field and component distribution under different air volumes, and the obtained data are processed and analyzed. The results show that when the central wind speed is less than 6 m/s, the central wind rigidity is poor, the average flow field velocity is low, and it cannot resist the return of high temperature flue gas. When the central wind speed is more than 8 m/s, it is easy to cause turbulence in the backflow zone, affecting the uniformity and stability of the power field. If the center wind increases 5 m/s the ignition point position will be postponed by about 6%, while the maximum temperature of coal powder ignition increases by about 34%. This is because the rigidity of the central wind is constantly increasing,thereby guiding the flue gas recirculation area to converge and form a high-speed airflow field, and quickly igniting the air-powder mixture to achieve full combustion. Reference | Related Articles | Metrics

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Research on Residential Peak-Valley Time-of-Use Electricity Price Scheme for in Hunan Province HUANG Minqi, DAI Dandan, ZHANG Li, LIAO Jing, PAN Xin Hunan Electric Power    2023, 43 (6): 63-67.   DOI: 10.3969/j.issn.1008-0198.2023.06.010 Abstract （1170）      PDF（pc） （4115KB）（87）       Knowledge map    Save Aiming at the problem of power grid consumption structure in Hunan Province, the strategy of residential time-of-use electricity price scheme is proposed. Based on the residential electricity load data, the hierarchical clustering method is applied to divide the peak and valley periods of residents. Based on the heterogeneity of residential electricity demand, a demand price elasticity model is constructed, and on the basis of the current residential tiered electricity price policy, and with the goal of peak shaving and valley filling, a peak-valley time-of-use electricity price scheme for residents in Hunan Province is formulated. Reference | Related Articles | Metrics

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Configuration Optimization and Performance Analysis of Supercritical Carbon Dioxide Power Generation and Energy Storage Integrated System ZHU Guangming, CHEN Xun, HE Honghao, SUN Ruiqiang, XIE Guohong, YANG Yi, WANG Yangguang Hunan Electric Power    2024, 44 (4): 1-10.   DOI: 10.3969/j.issn.1008-0198.2024.04.001 Abstract （1070）      PDF（pc） （14511KB）（150）       Knowledge map    Save To synergistically enhance the efficiency and flexibility of coal-fired power system, and promote the transformation of thermal power units, a scheme of using supercritical carbon dioxide (S-CO2) working fluid to construct a coupling system of coal-fired power generation and pumped thermal electricity storage (“source-storage-integrated” system) is proposed. Based on the first and second laws of thermodynamics, the design and off-design calculation models of the integrated system are developed, and the potential of the flexibility improvement and the energy efficiency of the heat storage-release process are analyzed. The results show that by integrating pumped thermal electricity storage technology on the basis of S-CO2 coal-fired power system, the minimum output power of the unit can be reduced from the original 30% rated load to zero, which greatly improves the peak regulation depth and operation flexibility. When 75% rated load is selected as the heat release condition, the output power can be increased by 23.59% of the rated load. In addition, the equivalent round-trip efficiency of the heat storage-release process of the integrated system is 78.64%. The sensitivity analysis of heat storage parameters shows that the optimal value range for the molten salt cold tank temperature is 405~420 ℃, and the value range for the atmospheric pressure water hot tank temperature is 70~75 ℃. Reference | Related Articles | Metrics

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Construction and Optimization of Distributed Photovoltaic Out‍put Forecast Model Considering Multiple Real-Time Mete‍oro‍logical Factors LU Xinxing, QU Zhenyu, HUANG Jiyuan, ZHAO Zijun, LI Yuliang, WU Donglin Hunan Electric Power    2024, 44 (6): 128-133.   DOI: 10.3969/j.issn.1008-0198.2024.06.018 Abstract （1063）      PDF（pc） （4297KB）（126）       Knowledge map    Save Aiming at the problem that the output power of photovoltaic（PV） power is affected by a variety of factors, showing randomness and intermittency, which leads to the difficulty of accurately predicting PV output. A method of distributed PV output forecastmodel construction and optimization considering multiple real-time meteorological factors is proposed. Firstly, according to solar irradiance, temperature, wind speed, daily irradiation duration and relative humidity,the abnormal PV data return to by Newton interpolation, and the missing data are filled in to complete the preprocessing of PV data. On this basis,the characteristics of numerical weather prediction under uncertainties are quantitatively selected and the PV predictors are extracted based on fuzzy weighted convolutional neural network. Finally, a PV power output forecastmodel is constructed based on least square support vector regression, and the model is solved. The experimental results show that the research method has a very high precision for the prediction of distributed PV output. Reference | Related Articles | Metrics

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Cause Analysis on Copper Shield Burst of 110 kV Cable Joint LI Shaobin, XIE Shilin, PENG Yong, TANG Wenbo, ZHOU Hai, FAN Fangkun Hunan Electric Power    2023, 43 (1): 121-126.   DOI: 10.3969/j.issn.1008-0198.2023.01.021 Abstract （999）      PDF（pc） （7716KB）（147）       Knowledge map    Save The copper shield burst caused by short-circuit breakdown of cable joints is prone to fire hazards in cable tunnels. This paper analyzes a typical 110kV cable joint copper shield burst accident and proposes that the copper shield burst of cable joints is caused by the compound action of two types of states, high temperature and high pressure, and the short-circuit breakdown process is accompanied by the cracking and ionization of insulating materials. The above viewpoint is verfied throgh the short-circuit high-current simulation test of the designed cable joint verifies the above viewpoint, the effectiveness of the current market mainstream use of the cable joint explosion-proof method is analyzed, and the design elements of the cable joint fireproof and explosion-proof are proposed. Reference | Related Articles | Metrics

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Coordinated Control Strategy of Reactive Power of Grid-Forming Inverter and SVG Parallel System CHEN Yandong, PEI Xinxin, FU Youze, LI Xuyang, ZHANG Mingyu, ZHOU Kehui, TANG Haiguo Hunan Electric Power    2024, 44 (2): 112-121.   DOI: 10.3969/j.issn.1008-0198.2024.02.015 Abstract （990）      PDF（pc） （9970KB）（119）       Knowledge map    Save Taking the static var generator (SVG) as an example,this paper proposes a coordinated reactive power control strategy for grid-forming inverter and SVG parallel systems to address the voltage stability issue. Summarize the operation status of the parallel system into four working conditions,and coordinate the reactive power of the grid-forming inverter and SVG injection common coupling point under different working conditions through working condition identification, reactive power compensation calculation,reactive power allocation strategy,and working condition switching,so that the parallel system can work stably and reliably in all situations.A model is built in MATLAB and simulation is conducted.The results show that the proposed control strategy can achieve fast identification and switching of operating conditions,calculation of reactive power compensation,allocation of reactive power,and fast support for common coupling point voltage. Reference | Related Articles | Metrics

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Research on Electrical Secondary Drawing Recognition Method Based on Joint Recognition of Bitmap and Vec‍tor Graphics QU Xu, LONG Yanping, ZHANG Wei, YUAN Chaoxiong Hunan Electric Power    2024, 44 (6): 97-103.   DOI: 10.3969/j.issn.1008-0198.2024.06.014 Abstract （979）      PDF（pc） （5425KB）（87）       Knowledge map    Save Aiming at the problem that existing research mainly focuses on the identification of electrical components in the secondary circuit of substations and neglects the determination of connection relationships,a method for jointly analyzing CAD electrical drawings using bitmap and vector graphics is proposed. Firstly, YOLOv8 object detection algorithm is used to identify electrical drawings in bitmap format,obtain the categories and positions of electrical components in the drawings, and then the vector graphic characteristics of CAD drawings are used to pick up the line segment information between connecting component symbols,generating a topology map with wires as nodes and wire connection points as edges. Finally,a depth first search method is used to traverse the topology map to determine the connection relationships between component symbols. This method combines the advantages of extracting component symbols from bitmap using object recognition methods and extracting line segments using vector graphics, resulting in high accuracy in electrical component recognition and accurate recognition of connection relationships. Reference | Related Articles | Metrics

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Overview of Control Technologies for Grid-Forming Wind Turbines WANG Yuwei, WEI Juan, HUANG Sheng, CHEN Daojun, QIU Fengliang Hunan Electric Power    2025, 45 (2): 3-12.   DOI: 10.3969/j.issn.1008-0198.2025.02.001 Abstract （935）      PDF（pc） （9458KB）（129）       Knowledge map    Save When traditional grid-following turbines are connected to the power grid on a large scale, issues such as a decline in the short-circuit ratio of the grid, weakened synchronization support capability, and reduced system inertia may arise. Grid-forming wind power generation technologies can mitigate fluctuations in system voltage and frequency, thereby improving the overall safety and stability of power system operation. Firstly, the grid-forming control system frameworks of two typical wind turbines are analyzed: the doubly-fed induction generator (DFIG) and the permanent magnet synchronous generator (PMSG). Based on the most common control strategies, including droop control, virtual synchronous control, and model predictive control, the advantages and disadvantages of these two frameworks are discussed in terms of inertia support capability, overload capacity, and stability. Subsequently, from the perspective of performance improvement, the frequency regulation, voltage control, and robustness of the two models are compared and analyzed. Furthermore, the research progress in control performance enhancement technologies for grid-forming wind turbines are summarized and the future research directions and the key technical challenges that need to be addressed are explored, aiming to provide insights and references for the advancement of grid-forming technologies. Reference | Related Articles | Metrics

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Improved Dual-Vector Model Predictive Torque Control Strategy Based on Extended Sliding-Mode Disturbance Observer for Permanent Magnet Synchronous Motor LI Xiaobao, LIU Juntao, ZHOU Weilong, LIANG Denghui, LONG Huan, ZHAO Zhe, LUO Zhaoxu Hunan Electric Power    2025, 45 (1): 121-129.   DOI: 10.3969/j.issn.1008-0198.2025.01.018 Abstract （908）      PDF（pc） （7222KB）（38）       Knowledge map    Save Aiming at the problems of large computation, obvious torque fluctuation, and prediction error due to parameter mismatch in traditional dual-vector model predictive torque control for permanent magnet synchronous motor, an improved dual-vector model predictive torque control strategy based on novel extended sliding-mode disturbance observer is proposed. Firstly, in order to reduce the control computation, a fast voltage vector selection tableis proposed with a graph of 12 sector voltage vector, the number of iterations is greatly reduced from 14 to 3. Then, to address the undesirable effects of motor parameter mismatch, the stator inductance value is estimated by the amount of error variation between the predicted and actual measured values at adjacent moments, the inductance updating mechanism is integrated, and a novel extended sliding-mode observer is proposed to enhance the robustness of the prediction model in the case of parameter mismatch. The MATLAB/Simulink simulation results show that the proposed strategy can reduce the rotor torque volatility, effectively reduce the unfavorable influence of the parameters change, and improve the stability of the prediction model. Reference | Related Articles | Metrics

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Dynamic Power Allocation Strategy for Hybrid Energy Storage System of Urban Rail Trains Based on Improved SAC Algorithm HE Qingchen, QIN Bin Hunan Electric Power    2024, 44 (4): 11-19.   DOI: 10.3969/j.issn.1008-0198.2024.04.002 Abstract （866）      PDF（pc） （9257KB）（82）       Knowledge map    Save To smooth out voltage fluctuations in the traction network of urban rail trains, a power dynamic allocation strategy based on a soft actor-critic (SAC) with reinforcement learning is proposed based on the use of on-board supercapacitor and ground hybrid energy storage system. It is used to improve the energy-saving voltage stabilization characteristics of DC traction network and realize the life protection of on-board supercapacitor. Firstly, an urban rail train dynamics model is established, and the PEC-SAC algorithm is proposed to address the problems of long training time and slow convergence of SAC algorithm in urban rail dynamic power allocation. The algorithm combines prioritized experience replay, emphasizing recent experience and cosine annealing, and improves the learning rate by increasing the sampling probability of the recent experience and dynamically adjusting the learning rate, which improves the training efficiency and convergence speed. Then the state space, action space, and reward function are set up to realize that the train learns the optimal energy control strategy for the hybrid energy storage system in interaction with the simulation environment. The simulation platform is built through the joint simulation of MATLAB/Simulink and PYTHON, and the results show that the method improves the voltage stabilization by 0.36% and reduces the energy consumption by 4.52% compared to the SAC algorithm. Reference | Related Articles | Metrics

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Short‍-Term Load Forecasting Method for Regional Power Grid Based on Segmented Prediction and Weather Similar Day Selection LIANG Haiwei, WANG Yangguang, DENG Xiaoliang, LIU Jing, WEN Ming, YU Zongchao, LI Wenying Hunan Electric Power    2024, 44 (5): 109-116.   DOI: 10.3969/j.issn.1008-0198.2024.05.017 Abstract （865）      PDF（pc） （5697KB）（64）       Knowledge map    Save In order to improve the accuracy of load forecasting for the four key periods of power grid operation, namely low valley load, noon peak load, waist load load, and evening peak load, a short-term load forecasting method based on segmented forecasting and weather similar day selection is proposed. Firstly, the paper analyzes the impact of different factors, including meteorological and economic factors, on the load of the regional power grid at different time periods, and select relevant features as the training set for construction.Secondly, the paper adopts a long short term memory neural network model to achieve load forecasting for different time periods. Using mutual information and Euclidean distance, the paper selects similar days with weather conditions close to the day to be predicted, and uses the load curve of that day as a reference,combining with the segmented load forecasting results as the load forecasting result for the day to be predicted. The experimental results show that the proposed short-term load forecasting method can ef‍fectively improve the accuracy of short-term load forecasting, especially for low valley, noon peak, waist load, and evening peak periods, with a significant improvement in prediction accuracy. Reference | Related Articles | Metrics

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New Type of Environmentally Friendly Three-Phase Common Enclosure Basin Insulator for GIS Busbar ZHAO Junqing, GAO Yang, WU Wenhai, DAI Tongling, CHEN Yu, LIU Dongyang Hunan Electric Power    2024, 44 (2): 97-103.   DOI: 10.3969/j.issn.1008-0198.2024.02.013 Abstract （781）      PDF（pc） （9711KB）（82）       Knowledge map    Save This article provides a detailed introduction to the design features of the new 126 kV three-phase common enclosure basin insulator and uses finite element analysis software to perform detailed calculations and analysis of its insulation and mechanical performance.The research results show that by increasing the grounded shielding ring,the electric field intensity in the three-phase junction area can be effectively reduced.The design structure of the basin insulator with a circular convex platform can withstand high gas pressure values.During the casting process,applying a special material surfactant agent on the surface of the central component can effectively improve the bonding strength of the component.The insulator passed successfully a complete set of type tests,further confirming its high insulation performance and mechanical reliability. Reference | Related Articles | Metrics

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Analysis of Voltage Stability Capability of Dynamic Reactive Power Compensation Devices Supporting High Proportional New Energy Systems ZHANG Ruiqi, LI Mengjiao, YANG Hongming, ZHAO Jian, XU Qiufei, ZHANG Shijie Hunan Electric Power    2024, 44 (4): 27-33.   DOI: 10.3969/j.issn.1008-0198.2024.04.004 Abstract （656）      PDF（pc） （9695KB）（139）       Knowledge map    Save In response to the voltage stability issue in high proportion new energy access areas, the characteristics of new energy output gap and weak transient reactive voltage regulation ability of new energy units are first considered. Starting from the penetration rate of new energy and the power grid strength of new energy access points, and the mechanism of voltage instability in high proportion new energy access areas is revealed. Then, the dynamic reactive power output characteristics of SVC, SVG, phase-shifting camera, and distributed phase-shifting camera are elaborated, and the support capabilities of four types of reactive power compensation devices in high proportion new energy scenarios are compared and analyzed. Distributed phase-shifting cameras have more advantages in supporting reactive voltage and suppressing overvoltage/undervoltage in new energy stations. Finally, taking the Xiangnan new energy access area as the research scenario, the support effect of reactive power compensation equipment under fault conditions with the same new energy penetration rate and different new energy penetration rates is analyzed to verify the correctness of the proposed viewpoint. Reference | Related Articles | Metrics

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Cause Analysis and Preventive Measures of Wind Turbine Blade Tower Sweeping LUO Yanfei, XIAO Changyuan , SUN Maowen, LUO Shengxi, ZHANG Hualian Hunan Electric Power    2023, 43 (1): 116-120.   DOI: 10.3969/j.issn.1008-0198.2023.01.020 Abstract （621）      PDF（pc） （4564KB）（336）       Knowledge map    Save In recent years, there have been a number of blade tower sweeping failures of wind turbine in China, which have seriously affected the safe operation of wind turbines, and also brought a lot of economic losses. This paper analyzes the causes of blade tower sweeping failure in a wind farm from the aspects of clearance design, hoisting maintenance, blade quality, unit operation control, site adaptability, simulation restoration, etc. It is determined that the blade tower sweeping in the wind farm are caused by turbulence overrun, negative shear, and blade installation angle dislocation. Preventive measures are given for different tower sweeping causes, and some suggestions are put up for the clearance design of new models. Reference | Related Articles | Metrics

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Transient Characteristic of MOESFET Based on Cosimulation Simulink with COMSOL GAO Bing, WANG Shuai, ZHONG Yongheng, SUN Yasen, ZHANG Shangchen, ZHOU Jie Hunan Electric Power    2022, 42 (5): 1-7.   DOI: 10.3969/j.issn.1008-0198.2022.05.001 Abstract （619）      PDF（pc） （5562KB）（1974）       Knowledge map    Save Power devices are one of the weak links in power electronic systems, and their failure has obvious multi-scale characteristics. It is of great significance to build a transient model that can consider the multi-scale characteristics of power devices for device condition monitoring and aging evaluation. Therefore, this paper takes MOSFET as the research object, constructs the field circuit joint simulation model of power device Simulink and COMSOL, and realizes the transient characteristic analysis of devices considering the interaction of device switching information and macro physical information by selecting the on current and on voltage drop as the model interaction information. The average temperature at the chip (shell temperature), the average temperature on the surface of the chip (junction temperature), the conduction voltage drop, the chip resistance and the maximum displacement of the solder layer are analyzed. The results show that the model can effectively consider the switching characteristics of devices and the interaction between macro fields, and lay the foundation for the digital twin model of devices. Reference | Related Articles | Metrics

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Detection Method of Metal Fitting Rust Defects for Overhead Transmission Lines Based on UAV Patrol of Deep Learning ZHANG Jiasheng, LIANG Jinxing Hunan Electric Power    2022, 42 (5): 75-78.   DOI: 10.3969/j.issn.1008-0198.2022.05.013 Abstract （577）      PDF（pc） （3274KB）（493）       Knowledge map    Save In order to improve the efficiency of UAV inspection of overhead lines and the intelligent detection efficiency of rust defects of overhead line metal fitting, a deep learning-based inspection method for rust defects of overhead lines metal fitting is proposed. Due to the characteristics of large environmental background, small target, and large difference in shooting angle and shooting light in the intelligent detection of metal fittings rust defects of overhead transmission lines, this paper uses image preprocessing algorithm to expand the data set. And YOLO is replaced by MobileNet′s backbone feature extraction network to improve the generalization ability and robustness of the algorithm, and the actual inspection images are used for experimental testing. In the test set validation, when the confidence threshold is 0.5, the P value is 0.92, the R value is 0.84, and the AP value is 91.34%. The results show that this method has a good detection effect on the rust defects of overhead line metal fittings, and can provide reference for the assessment of equipment health status. Reference | Related Articles | Metrics

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Research on Thermal Runaway Behavior of Blade Energy Storage Lithium Batteries Based on Acoustic Detection Technology XU Song, WAN Tao, LI Xin, WU Junjie, ZHA Fanglin, WEI Jiaqiang, CAI Yufeng, LIU Yiyi Hunan Electric Power    2024, 44 (5): 17-23.   DOI: 10.3969/j.issn.1008-0198.2024.05.003 Abstract （541）      PDF（pc） （11069KB）（189）       Knowledge map    Save With the large-scale application of electrochemical energy storage, thermal runaway detection and timely warning research of lithium battery is of great significance for ensuring the safe operation of energy storage power station. In this paper, a test platform for the thermal runaway performance of lithium battery is set up. The sound signal of blade energy storage lithium battery under thermal runaway condition is tested. The acoustic characteristics and change rules of different development stages of thermal runaway such as battery bulging, pressure relief valve opening, venting, explosion and fire are analyzed. It shows the effectiveness of sound feature for thermal runaway detection. Aiming at the problem that the sound characteristics of thermal runaway are easily disturbed by the noise of other equipment such as ventilation fans and PCS in the energy storage battery compartment, an anti-interference analysis method of thermal runaway sound signal based on wavelet packet decomposition and spectral subtraction speech enhancement is proposed. The analysis result shows that the proposed method can effectively eliminate the wind noise interference from the thermal runaway sound signal, and can accurately restore the battery thermal runaway sound characteristics. After denoising, the correlation coefficient between the original and the denoised sound signals reaches 0.96. The results can provide as technical reference for thermal runaway detection and early warning of the energy storage lithium battery. Reference | Related Articles | Metrics

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Design and Simulation of Power Supply-Traction-Hybrid Energy Storage System for Urban Rail Trains ZHU Zhiqiang, WANG Xin, QIN Bin Hunan Electric Power    2024, 44 (1): 24-31.   DOI: 10.3969/j.issn.1008-0198.2024.01.004 Abstract （502）      PDF（pc） （7016KB）（314）       Knowledge map    Save In order to further improve the recovery and utilization efficiency of urban rail train regenerative braking energy, a structure of urban rail train traction power supply system based on distributed ground hybrid energy storage is designed through the analysis of system functional requirements, and the power supply network, train traction and energy storage system models are established. Moreover, aiming at the problem that low pass filtering leads to a large amount of power exchange between lithium batteries and supercapacitors, a stepped power allocation method with supercapacitor compensation is proposed.This method has small computation and strong real-time performance,and can avoid the internal power circulation of the hybrid energy storage system. Combined with the proposed model and strategy, MATLAB Simulink is used to simulate.The results validate that the energy utilization efficiency of the hybrid energy storage system is improved by 1.39%, the voltage regulation rate is increased by 12.75% and the energy saving rate is increased by 6.72%. Reference | Related Articles | Metrics

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Measures of Performance Optimization and Improvement of Three-Phase Inconsistent Protection for Circuit Breaker GUO Yang, CHEN Hao, GAO Shiyu, GU Hao, LI Yifeng Hunan Electric Power    2022, 42 (5): 90-94.   DOI: 10.3969/j.issn.1008-0198.2022.05.016 Abstract （498）      PDF（pc） （4167KB）（193）       Knowledge map    Save Based on the typical secondary circuit, this paper introduces the principle of three-phase inconsistent protection in high-voltage power system, analyzes the causes of protection maloperation from the aspects of circuit insulation fault, artificial factors, improper setting of pressure plate and so on, and puts forword the optimization and improvement measures. The application practice shows that the optimized measures are feasible and effective, and the performance of three-phase inconsistent protection is greatly improved. Reference | Related Articles | Metrics

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Research Progress and Prospect of UAV Inspection of Substation Equipment LI Huipeng, HUANG Daochun, DENG Yongqing, LI You, ZENG Zhaoqiang, RUAN Jiangjun Hunan Electric Power    2022, 42 (6): 32-39.   DOI: 10.3969/j.issn.1008-0198.2022.06.006 Abstract （498）      PDF（pc） （7644KB）（97）       Knowledge map    Save The use of UAV inspection of substation equipment can achieve multi-angle, refined and high-efficiency inspection of substation equipment. However, UAV inspection of substation equipment is still at the period of research and pilot application. Research perspectives are presented based on a review of the current state of relevant research. Before large-scale promotion, it is recommended to develop technical specifications and standards for UAV inspection of substation equipment and combineing the advantages of different trajectory planning algorithms to realize the intelligent planning of global static trajectory and local dynamic trajectory. In addition, a sample library of substation equipment defects is build and algorithms such as artificial neural networks is used to promote intelligent diagnosis of hidden defects. In view of the deficiencies in the existing safety distance study, it is recommended to fully consider the special characteristics of the substation environment, and propose a safety distance determination method for UAV operations in substations. The safety distance tests of UAV measurement and control performance under electric field and magnetic field environment are carried out and the safety distance criterion is proposed. In addition, the fast analysis method of safety distance of UAV near heterogeneous electrode/conductor is established by using machine learning and data fitting. Reference | Related Articles | Metrics

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Verification of Low Noise Unmanned Aerial Vehicle Rotor Noise Reduction in Power Inspection Applications LI Chengwei, LU Ling, DUAN Xinyu, XIE Yi, CAO Hao, WANG Lanbo, MA Wei Hunan Electric Power    2024, 44 (5): 45-49.   DOI: 10.3969/j.issn.1008-0198.2024.05.007 Abstract （497）      PDF（pc） （4672KB）（69）       Knowledge map    Save Unmanned aerial vehicles (UAVs） are widely used in power line inspection tasks due to their ef‍ficiency and flexibility. However, noise remains a critical challenge that needs to be addressed. This study employs beamforming technology to perform noise source localization and validate the noise reduction performance of a low-noise toroidal structure propeller. Through noise spectrum analysis and a virtual rotating array beamforming algorithm based on a microphone array, the noise of the toroidal propeller is compared with that of three other common propellers. Experimental results show that the toroidal propeller exhibits significant noise reduction in both broadband and tonal noise. Beamforming analysis further reveals that the primary noise source of common propellers originates from tips, while the toroidal design effectively mitigates tip noise, achieving noise reduction. Reference | Related Articles | Metrics

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Vibration Characteristics Analysis and Optimal Design of Oil-Immersed Transformer Based on Finite Element Method YUAN Fating, YAN Zhiwei, CAO Hao, JI Ruiqing, TANG Bo Hunan Electric Power    2024, 44 (1): 11-17.   DOI: 10.3969/j.issn.1008-0198.2024.01.002 Abstract （491）      PDF（pc） （3379KB）（198）       Knowledge map    Save According to the electrical and structural parameters of the oil-immersed transformer, the circuit magnetic field simulation model is established based on the finite element simulation software. Based on the experimental measurement results and the characteristic parameters identified by J-A hysteresis model, the magnetic property model of the material is obtained. The simulation model of transformer magnetic field-structure field is established to obtain the distribution of magnetic field and stress around the transformer. Taking the calculated core Maxwell force, magnetostrictive force and winding Lorentz force as excitation, the transformer vibration displacement considering the magnetic properties of the material is calculated. The vibration displacements at different positions of the core are extracted, and the distribution rules of the vibration characteristics of the core are obtained. On this basis, in order to reduce the vibration of the oil-immersed transformer, the finite element method is combined with the time-experimental design method, and the optimal parameters are obtained by adjusting the winding parameters of the transformer. The results show that the maximum vibration displacement of the transformer before and after optimization is 6.12 μm and 5.71 μm respectively, and the optimization method significantly reduces the vibration of the transformer, which has important guiding significance for the vibration and noise reduction of oil-immersed transformer. Reference | Related Articles | Metrics

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Improved Three-Vector Model-Free Predictive Current Control Strategy Based on Time Series for PMSM Drives XIAO Qianghui, ZHANG Yushuang, LUO Zhaoxu, CHENG Zhun Hunan Electric Power    2024, 44 (5): 29-36.   DOI: 10.3969/j.issn.1008-0198.2024.05.005 Abstract （490）      PDF（pc） （10263KB）（66）       Knowledge map    Save Aiming at the issue of poor parameter robustness of the conventional three‍-‍vector model predic‍tive current control strategy for permanent magnet synchronous motor drive systems, an improved three-vector model-free predictive current control strategy based on time series is proposed to eliminate the effect of parameter mismatch and enhance the robustness of the system. To begin with, a time-series data‍-driven model is established to fit the input-output data as a discrete transfer function and combined with the recursive least squares method to estimate the model undetermined coefficients online and predict the required variables. In addition, the vector sector is reclassified to optimize the selection process of the three-vector combination. Moreover, the vector duty cycle direct calculation method is introduced to suppress the uncertainty effect of motor parameter ingress on the duty cycle calculation link, which further improves the system robustness. Finally, the simulation and experimental results show that the proposed strategy can ef‍fectively improve the model parameter robustness. The dq-axis current ripple is reduced, and the disturbances caused by the variation of motor parameters can be effectively suppressed. Reference | Related Articles | Metrics

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Research on Monitoring and Management of Wind Power Generation Capacity in Hunan Power Grid CHEN Haoqi, WU Yuxiang, FAN Jiahong, QIAN Jun, CHEN Bin, ZHU Shu, ZHANG Jinfan Hunan Electric Power    2023, 43 (2): 97-101.   DOI: 10.3969/j.issn.1008-0198.2023.02.016 Abstract （487）      PDF（pc） （4797KB）（315）       Knowledge map    Save In view of the current situation and existing problems of wind power capacity monitoring technology in Hunan power grid, a wind power capacity monitoring algorithm and system architecture based on abnormal data identification are proposed. The feasibility of the algorithm is verified by historical data, which realizes real-time monitoring of wind power plant capacity and automatic detection and identification of wind power plant abnormal data.Based on the monitoring system, the supporting management suggestions are put forward to scientifically guide the improvement of the wind power management level of Hunan power grid, which can improve the wind power supply support ability and promote the development of wind power anti-ice technology. Reference | Related Articles | Metrics

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Review on Non-Contact Voltage/Electric Field Sensors KE Kun, YANG Qing, QIU Zhenhui, LIAO Wei, ZHOU Jianglin Hunan Electric Power    2023, 43 (5): 71-78.   DOI: 10.3969/j.issn.1008- 0198.2023.05.011 Abstract （480）      PDF（pc） （9478KB）（239）       Knowledge map    Save Safe and accurate acquisition of electrical parameter data of the power system can ensure the safe and stable operation of the power system. Compared with traditional voltage measurement, non-contact measurement technology has higher safety because it does not need to have a direct electrical connection with the primary equipment, and has the characteristics of small size, frequency bandwidth, and good transient response characteristics, which can meet the needs of modern power grid distributed sensor networks. This paper introduces in detail the technologies of coupling capacitive voltage sensing, voltage sensing based on current integration method, D-dot electric field sensing, electric field sensing based on electro-optical effect, piezoelectric effect, and electrostatic induction effect, analyzes the advantages and existing problems of the above sensing technology, and introduces the method of electric field inversion voltage. Finally, the development prospect of non-contact voltage/electric field sensing technology is prospected. Reference | Related Articles | Metrics

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Multi-Fault Analysis and Diagnosis of Inverters Based on CGAN and LSTM TIAN Rui, LIU Weike, WU Xun, ZHANG Xiaomin Hunan Electric Power    2023, 43 (6): 151-158.   DOI: 10.3969/j.issn.1008-0198.2023.06.023 Abstract （476）      PDF（pc） （19707KB）（107）       Knowledge map    Save Inverter is widely used in UPS, motors, and renewable energy generation systems. Its safe operation is of great significance for converter systems. In harsh working environments, the power transistor and current sensor of grid connected inverter are prone to faults, and their fault characteristics are similar and coupled, posing great challenges to existing inverter fault diagnosis technologies. Therefore, this paper proposes a coupling fault diagnosis method based on conditional generative adversarial network(CGAN)and long short-term memory(LSTM)for inverters. First, the basic working principle of the inverter is analyzed and a digital model is established on the dSPACE platform. Next, the working modes under single power transistor open circuit fault, double power transistor open circuit faults and zero output fault of the current sensor are explored through the model. Then, three phase currents are used as diagnosis variables, and CGAN is utilized to obtain the fault data which is closed to the real operation conditions. The faults of switches and sensors are finally located by the LSTM network. The experimental data proves the effectiveness of this method. Reference | Related Articles | Metrics

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Research Progress on Safety Performance Improvement of Lithium-Ion Batteries HE Dan, HU Xiongxiong, CUI Hao Hunan Electric Power    2024, 44 (3): 25-33.   DOI: 10.3969/j.issn.1008-0198.2024.03.004 Abstract （468）      PDF（pc） （6708KB）（606）       Knowledge map    Save :Aiming at the thermal runaway of lithium ion battery and fire fighting technology, the existing types of fire extinguishing agents are introduced, their fire extinguishing mechanism and advantages and disadvantages are analyzed, the mechanism and evolution process of thermal runaway of lithium ion battery are studied, and the future of lithium ion battery fire extinguishing agents is prospected.The research results show that these fire extinguishing agents meet the basic characteristics of extinguishing open fire when dealing with lithium-ion battery fires, but there are still different degrees of reignition risk, fire extinguishing time and flame retardant effect are not the same,in addition some fire extinguishing agents will have a negative impact on the environment and equipment after use. Therefore, the development of new fire extinguishing agents with high efficiency,environmental protection and anti-reignition characteristics is an inevitable trend of future research. Reference | Related Articles | Metrics

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Fault Location of Distribution Network Hierarchical Model Based on Improved Whale Algorithm ZHANG Shangde, ZHANG Lian, ZHAO Mengqi, JIA Hao, XIE Wenlong, JI Hongyu, HUANG Wei Hunan Electric Power    2023, 43 (1): 1-7.   DOI: 10.3969/j.issn.1008-0198.2023.01.001 Abstract （464）      PDF（pc） （5596KB）（188）       Knowledge map    Save After a large number of distributed power sources are connected to the distribution network, the dimension of the network structure and the uncertainty of the power flow direction when a fault occurs are increased. In view of the information distortion and the complexity of fault location when collecting or uploading fault current information, a fault location solution method is proposed, which establishes a mathematical model according to the network structure of distribution network, constructs a hierarchical model with the idea of hierarchical simplification, greatly reduces the variable dimension of distribution network, constructs a switching function and adds fault auxiliary criteria, and then improves the whale algorithm by population distribution, adaptive weight adjustment and cross-border treatment. The simulation results show that the proposed method can accurately locate the fault section and improve the efficiency and accuracy of distribution network fault solution under various working conditions, such as single fault, multiple faults, distorted current information or switching state of distributed generation. Reference | Related Articles | Metrics

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Study on Wind-Proof of Indirect Air Cooling Tower with Vertical Layout CHEN Yun, WANG Limin Hunan Electric Power    2022, 42 (5): 16-21.   DOI: 10.3969/j.issn.1008-0198.2022.05.003 Abstract （462）      PDF（pc） （6457KB）（223）       Knowledge map    Save The air cooling system is greatly affected by the change of external climate. When the wind speed increases or the temperature rises, the heat transfer capacity of the air cooling radiator decreases, thereby leading to the rise of the unit's back pressure. In order to make sure the unit operating safely, some measures should be taken to reduce the influence of high wind speed. In this paper, the flow field distribution and heat dissipation capacity of four models are simulated under high wind speed. According to the analysis and comparison of flow field distribution and heat dissipation capacity data, the heat dissipation capacity of indirect air-cooling tower is as follows: wind-proof wall outside the tower, adjusting shutter, cross wall inside the tower, without any wind-proof measures. Reference | Related Articles | Metrics

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Principle and Implementation Method of Remote Standby Automation in Substation Based on 5G Communication Mode YIN Chaoyong, LI Gang, LI Hui, XU Biao, LIU Weiliang, XIONG Shangfeng Hunan Electric Power    2023, 43 (1): 58-62.   DOI: 10.3969/j.issn.1008-0198.2023.01.010 Abstract （461）      PDF（pc） （4241KB）（103）       Knowledge map    Save In order to solve the problems of high cost of optical fiber laying in medium and low voltage power grid and difficult application of remote backup automatic switching, this paper provides a principle and implementation method of remote backup automatic switching in substation based on 5G communication mode. By setting a 5G router in each remote backup automatic switching, the router realizes the point-to-point communication of remote backup automatic switching in GRE TAP mode, so as to realize the information exchange of remote backup automatic switching in substation. The simulation model built in RTDS proves the feasibility of the proposed remote backup automatic switching scheme based on 5G communication technology. This method does not need to change the original hardware and software of the remote standby self-switching device, and avoids the need of adding optical fiber channel and so on, which makes the remote standby self-switching device more convenient and reliable.The structure is simple, and anti-interference ability is strong, which greatly increases in the low-voltage power network application possibility. Reference | Related Articles | Metrics

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Research on Stator Bar End Electromagnetic Shielding for Pumped Storage Generator NIE Liangliang, TAO Shidi, LI Tianwei, LIU Lei, LI Bin, WANG Qi Hunan Electric Power    2023, 43 (1): 110-115.   DOI: 10.3969/j.issn.1008-0198.2023.01.019 Abstract （454）      PDF（pc） （6109KB）（113）       Knowledge map    Save Based on the analysis of the transient electromagnetic field for the electromagnetic shielding of generator stator bar, the model boundary is selected in theory, which can take into account both the calculation speed and the calculation precision. The calculation models of two wire rods in the same slot and multiple wire rods in different slots are established to calculate the influence of adjacent wire rods on the electric field distribution. At the same time, the three-dimensional calculation model of a single bar is established to calculate and analyze the distribution characteristics of the axial and normal field intensity of the bar. The results show that the surface potential of the end of the bar after leaving the notch is close to the phase potential, and the maximum field strength appears at the lap of the high and low stopbands. In order to improve the distribution of field strength and potential, this paper puts forward measures to improve the distribution of field strength on the surface, adding high-resistance materials to the original high-low resistance overlap layer to keep the same as the original design scheme, while the original high-resistance layer is coated with low-resistance materials, which can greatly suppress the field strength and potential at the end of the wire rod. Reference | Related Articles | Metrics

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Electrodynamic Calculation of Cable Short Circuit Based on Finite Element Electromagnetic Simulation XU Binbing, CHEN Ziyao, LIU Yubin, LEI Jiacheng, QIN Rui, YANG Xin Hunan Electric Power    2023, 43 (1): 23-29.   DOI: 10.3969/j.issn.1008-0198.2023.01.004 Abstract （451）      PDF（pc） （6715KB）（330）       Knowledge map    Save When a short-circuit fault occurs in the cable line, the mechanical properties of the cable bracket and hardware will be threatened under the action of short-circuit electric power. The traditional method of calculating cable short-circuit electric force is formula method. The formula method can only calculate the maximum short-circuit electric force, and there are limitations such as single solution object and inability to reflect the change of force with time. In this paper, the finite element calculation method based on electromagnetic coupling is used to establish the finite element calculation model of cable short-circuit electrodynamic force. Based on Maxwell 's electromagnetic theory and Gauss divergence theorem, the transient electromagnetic field analysis of the cable is carried out, and the change of short-circuit electrodynamic force on the cable with time is obtained. Compared with the calculation results of the formula method, there is only 2.11% error. The results show that the calculation method of short-circuit electrodynamic force based on finite element electromagnetic simulation can intuitively obtain the distribution and vibration frequency of electrodynamic force at each moment during short circuit. The electrodynamic calculation method of finite element electromagnetic simulation can be applied to short-circuit analysis of other fault types. Reference | Related Articles | Metrics

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Forecast of Daily Maximum Load of Distribution Network Based on Hausdorff Shape Clasification ZHOU Wangfeng, LI Yong, GUO Yixiu, QIAO Xuebo, DENG Wei, LUO Weicheng Hunan Electric Power    2021, 41 (1): 1-5,10.   DOI: 10. 3969/j. issn. 1008-0198. 2021. 01.001 Abstract （449）            Knowledge map    Save The accurate prediction of daily maximum load and its occurrence time are the focus of economic dispatch and safe operation of distribution network. This paper studies the internal law of daily maximum value and its occurrence time of various types of load,and proposes a forecasting method of daily maximum load and its occurrence time combined with Hausdorff load shape classification and holiday correction in the same period of last year. Firstly， the shape characteristics of daily load are analyzed, and the load types are classified by Hausdorff distance algorithm. Then, the corection effect of holidays in the same period of last year in the prediction of daily maximum load and its occurrence time are analyzed, and it is used as the forecast input together with the recent daily load, temperature and other data. Finally, based on ElasticNet regression algorithm, the daily maximum load and its occurrence time prediction model are constructed for each type of load. Taking the load data of a certain station area in Hunan province as an example, the daily maximum load and its occurrence time in the Spring Festival of the station area are predicted and the accuracy and effectiveness of the method are verified in an example. Related Articles | Metrics

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Design of Ancillary Damping Controller of Grid-Forming VSC-HVDC Systems WANG Canlin, ZHANG De, ZHU Sirui, LI Yong, WANG Weiyu, WEN Ding Hunan Electric Power    2024, 44 (2): 68-76.   DOI: 10.3969/j.issn.1008-0198.2024.02.009 Abstract （446）      PDF（pc） （11931KB）（74）       Knowledge map    Save Voltage source converter based high voltage direct current system can provide inertia support to the receiving-end power systems. However,it also inherits the oscillatory characteristics of synchronous generator,which makes the system dynamics more complex.This paper establishes the state-space model and transfer function models of a grid-forming VSC-HVDC system connected with a receiving-end power system,which are utilized to reveal the system oscillatory characteristics under the disturbance.Ancillary damping controllers are designed to improve the damping performance of the grid-forming VSC-HVDC systems,which only requires the state variables of the grid-forming VSC-HVDC systems.The test system is built in DIgSILENT/PowerFactory to verify the performance of the proposed control strategy.The results show that the proposed control strategy can effectively dampen the dc voltage oscillation and the electromechanical oscillations in AC grids. Reference | Related Articles | Metrics

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Study on Voltage Sag Flexible Management Strategy with Energy Storage Device ZENG Jinhui, HUANG Xi, WANG Can, LAN Zheng, LIANG Bowen Hunan Electric Power    2022, 42 (4): 33-39.   DOI: 10.3969/j.issn.1008-0198.2022.04.007 Abstract （437）      PDF（pc） （3665KB）（258）       Knowledge map    Save In order to reduce the influence of power grid voltage sag on the safe operation of sensitive loads, this paper proposes a flexible voltage sag management strategy with energy storage device, which can take into account voltage sag management while peak clipping and valley filling. Firstly, the DC component of power grid voltage is extracted by differentiating the dq component of power grid voltage to realize the accurate detection of power grid voltage sag amplitude and phase, and achieve the effect of improving the dynamic response speed of the system. Secondly, in the power grid voltage sag and recovery stage, the flexible switching strategy is used to realize the flexible compensation of sag voltage, so as to reduce the current impact of sensitive loads before and after voltage sag and ensure the steady-state accuracy of output voltage. Finally, a simulation model is built on MATLAB/Simulink platform to verify the correctness and effectiveness of the proposed flexible governance control strategy. Reference | Related Articles | Metrics

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Research on Intelligent Auxiliary Monitoring System Based on Big Data Mining and Rule Engine ZHOU Hui, WANG Yao, LUO Renqiang, DANG Junbang, XIAO Zhenxin, ZHAO Hang Hunan Electric Power    2023, 43 (3): 77-81.   DOI: 10.3969/j.issn.1008-0198.2023.03.012 Abstract （434）      PDF（pc） （4526KB）（198）       Knowledge map    Save With the purpose of improving the intelligent level of power plant monitoring, this paper introduces an intelligent auxiliary monitoring system based on big data mining and rule engine, supported by big data technology and relying on various advanced machine learning algorithms. The system establishes the early warning model of all kinds of systems and equipment in power generation enterprises, which can accurately detect abnormal status of parameters and equipment, and reduce the monitoring pressure of operators. Early warning should be carried out in the early stage of equipment failure, and fault identification and troubleshooting guidance should be given to the early warning. The test results show that the system is beneficial to realize more comprehensive monitoring of equipment status in power plant, and it can further improve the operation level of units and the health level of equipment. Reference | Related Articles | Metrics

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Transformer Core Vibration Damping Technology and Three Types of Damping Rubber Performance Testing WU Xiaowen, ZHAO Ruidun, LI Shengli, CHEN Wei, HU Sheng Hunan Electric Power    2022, 42 (6): 40-45.   DOI: 10.3969/j.issn.1008-0198.2022.06.007 Abstract （429）      PDF（pc） （7667KB）（100）       Knowledge map    Save A physical model of 10 kV oil-immersed distribution transformer is established to study the vibration mechanism, transmission law and damping effect of transformer core and oil tank, the vibration displacement data of transformer oil tank surface at different time with and without iron core damping gasket are analyzed. It is proved that the vibration amplitude and noise emission of oil tank can be reduced by adding damping device between oil tank and iron core to increase the loss of vibration energy in the process of transmission. According to the characteristics and application requirements of transformer oil, cork rubber, nitrile rubber and fluorine rubber were selected to test their oil resistance. The test results of damping performance show that cork rubber and NBR can not satisfy the noise suppression condition of transformer, and will increase the noise to some extent under the condition of load, the fluorine rubber damping pad can meet the requirements of vibration and noise suppression of transformer, and can effectively reduce the noise. It can be used as a potential damping pad material for oil-immersed transformer iron core. Reference | Related Articles | Metrics

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Fault Diagnosis Study of Oil-Immersed Transformers of Optimized Kernel Based Extreme Learning Machine Based on Modified Aquila Optimizer YI Lingzhi, LONG Jiao, WANG Yahui, HUANG Jianxiong, SUN Tao, YU Huang, YU Guo Hunan Electric Power    2022, 42 (6): 7-14.   DOI: 10.3969/j.issn.1008-0198.2022.06.002 Abstract （426）      PDF（pc） （8655KB）（118）       Knowledge map    Save In order to improve the accuracy and reliability of oil-immersed power transformer fault diagnosis, an oil-immersed power transformer fault diagnosis method of optimized kernel based extreme learning machine (KELM)based on the modified aquila optimizer (MAO)is proposed in this paper. The original aquila optimizer (AO) is improved by using Tent chaotic mapping and cardinality probability density function, and the improved algorithm effectively improves the convergence speed and the accuracy of the optimization search.The optimal fault diagnosis model is constructed by jointly seeking the regularization coefficients and kernel function parameters in the KELM using the MAO algorithm. The experimental results show that the accuracy of MAO-KELM for transformer fault diagnosis reaches 95.8%, which is 3.52%, 10.07% and 11.64% higher than the optimized KELM fault diagnosis models of AO, GWO and PSO respectively, reflecting the superiority of the MAO algorithm,and comparing with the traditional model, the proposed method has obvious advantages in its diagnosis effect. Reference | Related Articles | Metrics

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Design of Digital Drive of High Power High Voltage DC Circuit Breaker Based on IGBT Device ZENG Jinhui, FAN Yangjie, HE Dong, LIU Xiang, LIAO Xiaobin Hunan Electric Power    2022, 42 (5): 8-15.   DOI: 10.3969/j.issn.1008-0198.2022.05.002 Abstract （422）      PDF（pc） （5057KB）（672）       Knowledge map    Save Aiming at the application of high power multi-switch, a new multi-function IGBT digital driver based on field programmble gate array(FPGA)is proposed, which is efficient, safe and reliable.The driver can make use of the full insulated gate bipolar transistor(IGBT)state detection circuit, multi-channel signal fault detection and protection circuit. In the test of multi-switch and high power 10 kV/5 kA circuit breaker, it is proved that the driver can ensure the validity of IGBT's functions such as voltage sharing, current sharing and temperature detection.The function of simultaneous shutdown is realized in 6.4 μs, the switching process of IGBT is optimized, and the safety and reliability of the whole circuit breaker is ensured. Reference | Related Articles | Metrics