最新刊期
卷 62 ， 期 6 ， 2026
- 摘要：The short circuti current, in case of flowing through a transformer, will generate an electro dynamic force proportional to the square of the current in the transformer, which may cause deformation or even damage to the transformer winding. Therefore, the transformer must possess the ability to withstand short-circuit current. In this paper, the short circuit withstand capability of transformer is firstly divided into such two aspects as the electrodynamicc force generated by the short circuit current in the transformer winding, and the mechanical strength that opposes it. The principles of those two aspects are described in detail. Then, the research progress on electrodynamics, mechanical strength, and multi field coupling, as well as various factors affecting short-circuit withstand ability, are discussed. Furthermore, the prospect of research on the short-circuit withstand ability of transformer is presented, which is of great significance for the short-circuit withstand ability of transformers. Finally, a summary is provided.关键词：transformer;leakage flux;short circuit current;mechanical strength;electromagnetic field;electrodynamic force86|42|0更新时间：2026-06-10
- 摘要：As a critical energy source for future power systems, renewable energy generation, primarily based on wind and solar power, has brought about numerous challenges such as volatility and intermittency to the power system. Energy storage devices play a key role in smoothing out fluctuations in renewable energy output and maintaining grid stability, in which, the power conversion system (PCS) , known as the energy storage converter, serves as the grid interface for energy storage equipment, and its control characteristics significantly influence the grid-connected performance of the energy storage unit. The traditional grid-following control converter has such issues as low power regulation and a lack of grid support capacity, the control mode of grid-forming (GFM) converter is successively proposed in the study. The energy storage unit in combination with grid-forming control strategy can effectively improve dynamic performance and stability of the grid side. In this paper the structure and characteristics of grid-forming converter and the grid-forming control mode of the commonly used VF control, GFM control based on PSL, VOC and matching control are described. The overcurrent protection and synchronization stability of the existing converter are also discussed. The synchronization stability methods of converter under small and large distrubances are introduced respectively. Finally, the application and future development trends of grid-forming control in energy storage are introduced.关键词：power conversion system;GFL control;GFM control64|43|0更新时间：2026-06-10
- 摘要：The intelligent operation and inspection of substation equipment cannot be separated from advanced equipment state sensing technology. With the intelligent development of power system, the demand for state sensing sensors of electrical equipment in substation has been increasing year by year. The steady state electromagnetic disturbance and transient electromagnetic disturbance in substation pose a great threat to the life of state sensing sensors, especially to the life of micro-power smart sensors, which lead to high error rate of online monitoring data and frequent false alarms. In this peper the statistical analysis of the actual steady-state and transient electromagnetic disturbance characteristics of substation provides theoretical support for the electromagnetic compatibility test requirements of the field electrical equipment state sensing sensors.关键词：state sensing;sensors;electromagnetic disturbance;steady state;transient state;EMC43|29|0更新时间：2026-06-10
Overview
- 摘要：As the grid load and the degree of interconnection between substations increase, the short circuit current level rises accordingly, driving the development of 1 100 kV/63 kA GIS toward 1 100 kV/80 kA based on existing equipment, which places higher demand on the arc ablation resistance performance of the enclosure. Currently, this performance is mainly evaluated through internal fault arc tests. However, due to the difficulty of conducting tests on UHV GIS, most assessments are performed by using numercial calculations. Nevertheless, numerical methods struggle to capture the combined effects of thermal-mechanical coupling. Furthermore, due to the limitations of numercial assessment methods, the evolution of arcing effects and the risk of structural failure in UHV GIS equipment under extreme fault conditions remain unclear. To address the issue, in this paper the GIS arcing effect assessment method considering thermal-mechanical effect is proposed on the basis of Mayr-Schwarz arc model and the assessment reliability is verified. Compared with the test result, the assessment error rate is less than 1%, indicating that the proposed assessment method and the selection of empirical parameters possess high reliability. Furthermore, based on the proposed method, the internal arcing effects of 1100 kV/63 kA GIS busbar compartment at 80 kA short circuit fault is analyzed. The assessment result shows that in case of 80 kA short circuit current for 0.3 s, the maximum pressure in the gas compartment can be up to 2.71 MPa, exceeding the enclosure maximum allowable pressure of 1.95 MPa of the busbar compartment enclosure, and the enclosure will be cracked from the weld seam. Such measures as optimization of thickness and internal diameter of enclosure as well as addition of pressure relief device are suggested. The relevant work can provide a necessary theoretical basis of arcing resistance performance of three phase independent encapsulated GIS at different voltage levels.关键词：UHV GIS;internal discharge;arc effects assessment;structural failure risk analysis86|42|0更新时间：2026-06-10
- 摘要：High-speed DC switch (HSS) is the key equipment for the online onnection/disconnection and fault isolation of the third station in the hybrid multi-terminal HVDC transmission system, and needs to have the capability to interrupt small DC current. In this paper the operating principle of current interruption by the HSS is analyzed based on circuit equation and the principle of energy conversion. An equivalent test method for the HSS to interrupt small current is proposed, and a test circuit fot the HSS for small current interruption is set up. As for the HSS prototype, the current interruption test of the HSS under different conditions is carried out, and the influence of the variation of the interrupted current, recovery voltage, opening speed of the moving contact of the interupter, gas filling pressure of interrupter and the diameter of the nozzle throat on the DC interruption performance of the HSS is studied. The test results show that the current amplitude and the opening speed have a significant impact on the current inerruption performance of the HSS, while the slight variation of recovery voltage, gas filling pressure of interrupter an throat diameter of nozzle have little influence on current interruption of the HSS. The effectiveness of the test data is verified by modeling and calculation. The study results in this paper has provided a basis for the design of DC high-speed switch HSS.关键词：DC high speed switch;hybrid multi-terminal UHVDC system;DC current interruption characteristics;DC arc voltage;prototype test29|18|0更新时间：2026-06-10
- 摘要：To address the limitations of traditional shallow machine learning in feature extraction and to enhance its capability for transformer fault diagnosis, a transformer fault disgnosis method based on KELM optimized by an improved sparrow search algorithm is proposed. First, the deep belief networks (DBN) is used for feature extraction of transformer fault sample data.Then, the kernel extreme learning machine (KELM) with penalty factor C and kernel function parameter S is used as a classifier to analyze deeply the correlation between features of confusable samples and fault types and improve the stability and generalization ability of the model.After that, the improved sparrow search algorithm (SSA) with Levy mutation factor is used to optimize the penalty factor C and kernel function parameter S of KELM to enhance the global search ability of the algorithm and improve both stability and accuracy of fault diagnosis of the model. Finally, the experimental results of transformer fault diagnosis based on dissolved gas data in oil show that the proposedISSA-KELMtransformer fault diagnosis method has faster convergence speed, better stability and higher diagnostic accuracy, and is suitable for transformer fault diagnosis.关键词：transformer;fault diagnosis;deep belief networks;kernel extreme learning machine;Levy factor;sparrow search algorithm26|11|0更新时间：2026-06-10
- 摘要：To doagnose transformer core looseness faults more effectively, a fault diagnosis method based on the improved complete ensembleEMD (ICEEMDAN) algorithm and the refined composite multiscale dispersion entropy (RCMDE) is proposed for the vibration signals of the transformer under load operation. First, the ICEEMDAN algorithm is used to decompose the vibration signal sequence of the transformer core under different degrees of looseness.Then, the entropy value of the eigenvalues is calculated by using RCMDE and Principal Component Analysis (PCA) and dimensionality reduction is carried out. Finally, the K-means clustering algorithm is used to classify and identify faults on the vibration data represented by multi-groups of low-dimensional eigenvalue matrices. Combined with the core looseness fault simulation experiment of a 10 kV transformer, the results show that, compared with traditional modal decomposition and eigenvalue extraction algorithms, the proposed K-means clustering based on ICEEMDAN-RCMDEachieves excellent clustering performance with an accuracy rate of 95.6% and can effectively identify transformer core loosenese faults.关键词：transformer;diagnosis of iron core looseness;vibration signal;ICEEMDAN algorithm;RCMDE18|10|0更新时间：2026-06-10
- 摘要：Dry distribution transformer is noisy and close to residents as well as prone to their dislike. For reducing effectively the noise of distribution transformer, the acoustic structure simulation of sound insulation materials based on the noise characteristics of distribution transformers is performed in this paper. It is found that the sound insulation performance of rigid sound insulation materials can be improved by adding damping layer, with adoption of constrained damping sound insulation structure in particular. On this basis, the acoustic test analysis of the damping sound insulation structure with different structural parameters constraints is performed. It is shown by the result that the rigid material has great influence on constrained damping sound insulation structures.With the increase of the rigid material thickness, the sound insulation performance increases obviously, but the increase amplitude decreases gradually.And the damping material can also improve the sound insulation performance of constrained damping structures. With the increase of the damping material loss factor, the sound insulation performance increases. With the increase of the damping material thickness, the sound insulation performance of low and high frequency band is improved, and the resonant frequency and critical coincidence frequency are adjusted to a higher band.关键词：dry distribution transformer;noise;constrained damping sound insulation structure;rigid materials;damping materials23|10|0更新时间：2026-06-10
- 摘要：Partial discharge (PD) is the initial sign of insulation deterioration in power transformer. The timely and accurate extraction of partial discharge signals is of great significance for transformer status monitoring. However, due to the influence of periodic narrowband interference and white noise, the noise suppression performance of such methods as traditional fast Fourier transformation (FFT) thresholding, wavelet denoising, and singular value decomposition (SVD) methods is are weak and are difficult to effectively extract PD information. In this paper, a transformer PD ultrasonic signal extraction method based on whitening filtering and radial basis function neural network-Kalman filtering (RBF-KF) is proposed. First, a whitening filtering matrix is constructed based on the characteristics of periodic narrowband interference signals, and this matrix is then used to preprocess the noise-cotaminated PD signal through wightening, theteby converting the periodic narrowband interference into white noise.Then, the Kalman filter (KF) model is set up for white noise suppression. Meanwhile, to address the issue that KF filtering results are prone to divergence, a radial basis fucntion neutral network (RBF) is used to dynamically correct the filtering errors, thereby improving the noise suppression performance. The experimental results based on simulation and measured data indicate that the proposed method has excellent noise suppression performance. Compared to traditional FFT threshold, wavelet denoising, and SVD methods, the waveforms of the partial discharge ultrasonic signals extracted by the proposed method have less distortion, less energy loss and greater engineering application prospects.关键词：power transformer;partial discharge;ultrasonic signal;whitening filtering;narrowband interference;noise suppression20|29|0更新时间：2026-06-10
- 摘要：The arcing fault of converter transformer will lead to damage to transformer and even to adjacent transformers or other electrical equipment, which will cause serious damage to substation and affect the safe and stable operation of the power grid. Aiming at the weak link of the converter transformer, namely arcing fault inside the elevated seat, the numerical simulation is used in this paper to perform the fault characteristics study under the internal fault condition of the converter transformer elevated seat, analyze the equivalent pressure and stress distribution of the elevated seat under different arcing energy of elevated seat. It is pointed out that under the arc energy enhancing the material properties of the wall can not achieve anti-explosion effects and it is therefore necessay to develop effective pressure relief measures.关键词：converter transformer;arc fault;numerical simulation27|14|0更新时间：2026-06-10
- 摘要：A deep learning method based on an improved stacked denoising autoencoder (SDAE-SVM) is proposed for pattern recognization of partial discharge (PD) signals generated by different insulation defects in high-voltage cables. First, PD tests are conducted on five types of artificial defects in a high-voltage laboratory, and 3500 sets of PD instantaneous pulses are extracted to construct 34 types of characteristic parameters. Then, the principles and network architecture ofSDAE-SVMare introduced in detail. After that, the proposed model is used to recognize the PD signals of different types of defects and the pattern recognition accuracy of 93.56% is obtained. Moreover, the the layer-wise outputs of theSDAE-SVMare visualized using t-distributed stochastic neighbor embedding (t-SNE) , illustrating the essence of layer-wise optimization of the deep neural networkSDAE-SVM. Finally, the proposed method is compared with back propagation neural network (BPNN) , support vector machine (SVM) and stacked denoising autoencoders (SDAE) . The results show that compared with BPNN, SVM, and SDAE, the overall recognition accuracy ofSDAE-SVMhas increased by 7.46% , 6.70% , and 1.37% , respectively, demonstraing high engineering application value .关键词：high voltage cables;partial discharge;pattern recognition;deep learning;stacked denoising autoencoder22|19|0更新时间：2026-06-10
- 摘要：Incipient faults in cables are often accompanied by intermittent arcing, with self-extinuishing of the arc occuring near the current zero-crossinng point, manifesting as self fault clearanc. However, the physical changes durig this process are still not well understood. Due to the very short duration of intermittent arc discharge, it is difficult for traditional relay protection equipment to identify incipient faults and appropriate features need to be extracted to identify incipient fault signals. In this paper, based on the magneto hydro dynamics theory (MHD) , the multiphysical field simulation of medium voltage cables is performed to analyze the variation of current density, magnetic field intensity and temperature distribution during a quarter cycle of intermittent arcing. Short-time Fourier transform (STFT) is performed on the simulation waveform so to obtain the frequency domain characteristics of the incipient fault. The results show that in case of incipient fault in cables there is a high frequency component, which is obviously different from the normal operation under the 5 kHz frequency treated by Hanning window, and the amplitude difference can be up to 85 dB. While, the Hamming window has a weak processing effect, so it is necessary to select or combine appropriate features for identification.关键词：self-fault clearance;intermittent arc;MHD;time-frequency transformation;fault identification23|16|0更新时间：2026-06-10
- 摘要：In this paper, an an electromagnetic time reversal fault location method based on the minimum mirror value of fault current energy is proposed. However, this method currently requires that the simulation model set up during the reverse stage to be consistent with the actual line model parameters at the time of the fault during the forward stage, which limits its practical application. Therefore, based on the discrepency in model parameters between the forward and reverse stages of this method, the PSCAD simulation software is used in this paper to set up a 10 kV distribution network line model and its frequency-domain theoretical derivation is conducted .Through simulation, the loalization performance of this method under different line parameter sensitivities is analyzed, and a coaxial cable experimental model is constructed for validation. The results show that：①When the line inductance parameters in the reversed stage are adjusted in the range of 0.95 times to 1.1 times compared to the line inductance parameters in the direct stage, the method is able to accomplish ground fault location with high resistance.②The method can achieve accurate location of the real occurrence of an unknown ground fault resistance, and it is suggested that a high-resistance fictitious ground fault can be set in the line's lateral branch in the reversed stage so to increase its overall location performance.③Using the constructed coaxial cable test model, the impact of unknown fault impedance on the fault location performance of the method is analyzed, with a maximum comprehensive fault localization error of 5 m.关键词：minimum mirror value of fault curren energy;electromagnetic time reversal;line parameter sensitivity;fault location;localization performance16|8|0更新时间：2026-06-10
- 摘要：Under the backdrop of“dual carbon”goals, the new power system dominated by new energy faces such challenges as insufficient rotational inertia, inadequate damping and significant frequency fluctuations. For this reason, an adaptive control strategy of grid-forming energy storage converter considering the state of charge of energy storage and frequency recovery is proposed. First, the small signal model of grid-forming energy storage converter is set up in this paper, and the influence of virtual inertia and damping coefficient on system characteristics is analyzed. Then, the virtual inertia and damping coefficient are designed using root locus analysis and dynamic response. On this basis, a regression function is introduced to construct a control factor among SOC, virtual inertia and damping coefficient. The energy storage state of charge and frequency recovery are included in the adaptive influencing factors of virtual inertia and damping, ensuring real-time adjustment of inertia and damping coefficient disturbances while ensuring the safety of the energy storage device. Finally, a simulation model is constructed in MATLAB/Simulink and both feasibility and effectiveness of the proposed strategy are verified by the simulation result.关键词：grid-forming converter;virtual inertia;virtual damping;frequency support20|9|0更新时间：2026-06-10
- 摘要：In the control incices of the modular multilevel converter (MMC) , the voltage balancing effect of the submodel and switching frequency of the insulated gate bipolar transistor (IGBTs) impose mutual constraints. To reduce the switching frequency while maintaining the voltage balancing effect, in this paper a voltage balancing strategy based on the optimization switching number is proposed. By analyzing the variation trend of voltage balancing effect and classifying the switching actions of IGBT, it is proposed to use the current arm current value to calculate the the switching number between inserted modules and removed modules. When arm current value is less than the set value and voltage balancing effect of SMs can be achieved in accordnce with modulation variation, the switching number is set to zero. Otherwise the threshold of voltage balancing effect is corrected in accordance with real-time arm current value, and the switching numbers are calculated based on the corrected voltage threshold, the direction of arm current, the corrected number of inserted modules and the sorting results of the submodule voltages. Finally, the trigger pulses are refreshed based on the corrected number of inserted modules and the switching number. This strategy can ensure the stability of voltage balancing at different power levels and, at the same time, reduce effectively switching frequency. The effectiveness of the proposed strategy is verified by constructing a simulation platform based on RTLAB real-time simulation system.关键词：modular multilevel converter;voltage balancing strategy;voltage balancing effect;switching frequency;switching numbers12|10|0更新时间：2026-06-10
- 摘要：In small current grounding system, in case of abnormal operating status, the resonance can be occurred between the distributed capacitance of the distribution line and the winding inductance on the primary side of the potential transformer (PT) , resulting in resonant overvoltage and, in case of serious cases, burning of PT, explosion and seriously threatening the safety of personal and equipment. In this paper the 10 kV distribution network of a 110 kV substation in Shanxi Province is taken as the research object, the simulation model is set up in PSCAD/EMTDC, and the influence of line distribution capacitance (line length) and PT capacity on the resonance characteristics is analyzed, and aVMD-HHT-WOA-SVMidentification algorithm is proposed for different types of resonance. It is found by the research that both the length of the line and the maginitude of PT capacity have an impact on the ferromagnetic resonance of the distribution network. In actual operating conditions, due to the influence of line parameters and PT excitation charcateristics, high-frequency resonance rarely occurs.The accuracy rate of the PT resonance recognition method based onVMD-HHT-WOA-SVMcan be up to 95% , enabling effective identification of both the resonance type and the moment of its occurrence.关键词：potential transformer;ferromagnetic resonance;resonance characteristic;VMD-HHT-WOA-SVM recognition algorithm18|11|0更新时间：2026-06-10
- 摘要：To verify the comprehensive design rationality of ±800 kV/5000 A UHV converter valve under multiple safety constraints, in this paper the numerical simulation analysis on the electric field of the full shielding system is performed based on the seismic verification-proven structural design scheme. A 1∶1 simplified three-dimensional model is set up using Solidworks. The electric field simulation calculation is performed based on the ANSYS Maxwell simulation software, in accordance with relevant standards and consideration of the application boundary conditions of the altitude correction factor as well as the use of the finite element method.The results show that, on the basis of ensuring excellent seismic performance, the maximum electric field strength at each part of the converter valve still satisfies the extreme operating condition control value of 2.0 kV/mm, 1.4 kV/mm for the top shield, 1.89 kV/mm for the bottom shield, 1.5 kV/mm for the layer shield, and 1.0 kV/mm for the interlayer water pipe, with uniform electric field distribution. Furthermore, a mechanical-electrical collaborative margin framework is proposed in combination with seismic data . It is demonstrated that the electric field strength of the bottom shield approaching the control value is not a the design defect, but a systematic trade-off of electrical performance under the premise of guaranteeing seismic performance. This work provides a referable methodology and engineering example for the multi-physics collaborative design of complex UHV equipment.关键词：ultra-high voltage direct current transmission;converter valve shielding system;electrostatic field analysis;finite element method;mechanical-electrical collaboration18|17|0更新时间：2026-06-10
- 摘要：To study the influence of grading ring fracture and inclination on electric field and potential distribution of composite insulators, the FXB3-110/100 composite insulator is taken as the research object . A physical model of the composite insulator is set up in ANSYS using the finite element method, and simulations are performed. The grading ring is modeled by changing its fracture position and inclination angle, and its influence on electric field distribution is then studied by the finite element analysis method. The results show that the fracture and absence of the grading ring on either high-voltage side or low-voltage side will cause the field strength of that side to increase and the field strength of the opposite side to drop abruptly. The grading rng fracture makes the potential concentrate on both sides. When the grading ring is completely fractured and falls off, the first 3% to 5% of the leakage distance on the high and low voltage sides carries 60% of the voltage drop. In case of inclination of the grading ring of composite insulator, the influence to the electric field mainly concentrates in the middle of the insulator string rather than the high and low voltage ends. A large inclination angle of the grading ring will increase the electric field intensity by about 40%, which is determental to the safe operation of the composite insulators.关键词：grading ring;fracture;incilination;finite element;electric field distribution12|14|0更新时间：2026-06-10
- 摘要：Temperature is one of the important factors affecting the formation and development of typical insulation defects in gas insulated switchgear (GIS) . For exploring the influence of temperature factors on the electric field distribution of defects on the insulating spacers, a 252 kV GIS electric-thermal-fluid multi-physical field coupling model is set up in this paper by using finite element software, and the electric field distributions on the spacer surface are obtained for different conductor temperatures, bubbles, cracks, and suspended metal particle defects in different locations, and the variation of electric field is analyzed further by the space surface charge distribution and calculation of critical breakdown field strength of gas. The results show that with the increase of conductor temperature the maximum field strength on the spacer surface increases accordingly under all three defects, with maximum increase under crack defect and minimum increase under suspended metal particles. The effect of temperature change on the electric field is related to the type and location of the insulation defects. The higher the temperature of the conductor, the electric field strength of the spacer surface around the suspended metal particles and the bubbles as well as cracks on the low-voltage side gradually increases, while the electric field strength of the spacer surface at the bubbles and cracks on the high-voltage side gradually decreases. The charge density of insulation defects on the low voltage side varies more significantly with temperature variation, and the electric field distortion ampli tude changes more significantly. The study results can be not onlyuseful for further understanding the effect of temperature variation on the electrical field distribution on the surface of insualtign spacer under bubbles, cracks and suspended metal particles defects, but also have some reference value for design improvement of the insulating spacer.关键词：gas insulated switchgear;multi-physics coupling;finite element analysis;electric field distribution23|12|0更新时间：2026-06-10
- 摘要：The adoption of virtual inertia control in wind power generation can not only increase system intertia and and improve the frequency dynamic process under large disturbance, but also significantly affect the frequency oscillation process simultaneously. In this paper, a mathematical model for the frequency response of the entire system is constructed by considering the synchronous generator prime mover and its governing system, the maximum power point tracking plus virtual inertia control of wind turbines, as well as static characteristic of the load. On this basis, the influence of wind turbine adopting virtual inertia control on the equilibrium point, inertia and damping characteristics of the entire system is derived and analyzed. A system with a high proportion of renewable energy is set up and verified by simulation, and the rationality of the analysis is described.关键词：frequency stability;virtual inertia control;renewable energy frequency regulation;damping characteristics;switching oscillation;equilibrium point11|10|0更新时间：2026-06-10
- 摘要：Pillar-type electrical equipment with high seismic vulnerability is installed in the upper modules of offshore platform structures such as offshore stations in wind farms.To investigate the seismic performance of such equipment, a finite element model is set up for the neutral point protection device of the 220 kV main transformer in a real offshore substation in China. The seismic responses analysis of the equipment is performed by the time-history analysis method. The results show that although the stress at the root of the porcelain bushing complies with the specification requirement, yet the low rigidity of the steel plate of the equipment mounting frame leads to excessive local stress at the connection between the disconnector and the steel plate in seismic condition, exists the damage risk and causes indirectly the damage of equipment. After applying base isolation control using isolation bearings to the original equipment, the stress and acceleration responses at critical locations of the equipment, as well as the peak stress of the equipment mounting frame, can be significantly reduced, thereby meeting the seismic design requirements.关键词：offshore substation;transformer neutral point protection device;FEM analysis;seismic response;seismic isolation16|11|0更新时间：2026-06-10
- 摘要：Flexible DC transmission offers significant advantage for large-capacity offshore wind power in deep and distant sea regions, and is an effective solution for integrating such wind power into the grid. However, research on offshore wind power transmission from deep and distant sea areas in China is still in its early stages, and there remains a certain gap compared to Europe. Currently, studiess on large-capacity bipolar offshore wind flexible HVDC systems at ±525 kV voltage level are still relatively scare.In this paper, based on the IJmuiden Ver ±525 kV/2 GW offshore wind DC transmission project of TENNET Power Grid Company in Europe, the typical symmetric bipolar topology, operation modes, main circuit parameters, as well as different operating modes and their switching relationships of the system are introduced. Based on relevant assumption conditions, the offshore wind power DC transmission model is set up in thePSCAD/EMTDCelectromagnetic transient simulation platform. Full operating condition fault scans are conducted on the system under various operatign modes, with a focus on analyzing the arrester configuration schemes for the offshore converter station and the onshore converter station. FInally, recommended insulation levels for key main equipment are provided based on insulation margin requirements. The research results can serve as a reference for future engineering projects with similar voltage levels both at home and abroad.关键词：symmetric bipolar;offshore wind flexible DC system;fault scanning;overvoltage and insulation coordination;arrester configuration scheme17|16|0更新时间：2026-06-10
- 摘要：SO2 is the main characteristic decomposition product of SF6-insulated electrical equipment under internal partial discharge and abnormal heating, which is of great significance for the diagnosis of latent defects in such equipment.Due to the large gas compartment and the installation of adsorbents in extra-high voltage (EHV) and ultra-high voltage (UHV) electrical equipment, the concentration of decomposition products generated by latent defects is usually lower than the minimum detection limit of field instruments. Therefore, there is a lack of effective detection devices and technical means for trace SO2 at present. In this paper, a trace SO2 detection device based on lowtemperature enrichment and ultraviolet fluorescence method is developed.Low-temperature enrichment liquefies most of the SF6 in the measured gas, elevating the SO2 concentration and thus improving the detection sensitivity. The ultraviolet fluorescence method for SO2 detection features small sample consumption and non-destructive measurement, making it suitable for combination with the low-temperature enrichment unit to realize the detection and analysis of SO2 at the 10-9 level.Experimental results show that the SO2 enrichment factor is approximately 10 times at an intake volume of 25 L, and about 20 times at 50 L. The device can detect SO2 at a concentration of 50×10-9.关键词：SF6 decomposition product;low-temperature enrichment;UV fluorescence;cold trap32|11|0更新时间：2026-06-25
- 摘要：C4F7N is a potential alternative gas to SF6 with promising application value. However, current research on C4F7N gas mainly focuses not on the arc interruption performance, but on insulation performance analysis.In this paper the post arc insulation breakdown performance ofC4F7N-CO2 mixtures at temperatures from 300 K to 3 500 K and pressures from 0.01 MPa to 0.1 MPa is studied. First, the partical composition of the arc in hot C4F7N-CO2 gas mixtures under different mixing ratios is obtained using the Gibbs free energ minimization method. Then, the electron energy distribution function, reduced ionization coefficient, reduced attachment coefficient, and reduced critical breakdown field strength of the post arc gas are calculated using the two-term Boltzmann equation. The influence of temperature, pressure, and CO2content on the insulation breakdown characteristics of the hot post-arc are also analyzed. It is found by research that the mixing of CO2 can significantly reduce the concentration of high-energy electrons, while the increase of pressure generally leads to a decrease in the probability density of high-energy electrons. Appropriately increasing the CO2 ratio can improve the insulation breakdown performance within the temperature ranges of 700 K to 1100 K and 2600 K to 3500 K. However, at low temperatures, excessive addition of CO2 to the mixture will reduce the insulation breakdown capability.关键词：Gibbs free energy minimization;Boltzmann equations;electron energy distribution function;critical breakdown electric field strength20|15|0更新时间：2026-06-10
- 摘要：C4F7N, an environmentally friendly gas with potential to replace SF6, has received widespread attention regarding its insulation charcateristics. Among these characteristics, the decomposition properties of C4F7N under micro-water and micro-oxygen cndition, as well the associated chemical kinetic process, constitute an important part of the research on C4F7N gas insulation performance. However, relevant studies, particularly theoretical investigations, remain relatively limited. Therefore, in this paper the C4F7N is taken as the object of discussion, the possible reaction path of C4F7N gas in micro-water and micro-oxygen environment is searched and verified through quantum chemistry calculation method. On this basis, the fitting parameters of Arrhenius formula corresponding to the reaction path at different temperatures are calculated, and the reaction rate coefficient within the given temperature range is obtained. Furthermore, the kinetic model of chemical reaction of C4F7N gas in micro-water and microoxygen environment is established by using the calculated reaction rate coefficient, and the influence of temperature and micro-water as well as micro-oxygen content on the products of C4F7N gas reaction system is studied. It is found by the study that the stable products generated in the micro-water environment includeC3F7CONH2, (CF3) 2CCNOHand those generated in the micro-oxygen environment includeF2CO, (CF3) 2CFO, COetc. With the increase of temperature, the reaction rate is accelerated and the time of stable product formation is shortened. With the increase of the content of micro-water and micro-oxygen, the mole fraction of the generated stable product also increases proportionally.关键词：environmentally friendly insulating gas;quantum chemistry;reaction rate coefficient;chemical reaction kinetics14|13|0更新时间：2026-06-10
Research & Analysis
- 摘要：For exploring the variation of arc pressure durign the arcign process of fuse, a internal pressure detection method for fuse is firstly designed and the internal pressure measurement can be achieved through the coordination of external bracket and pressure sensor. Then, the accuracy and feasibility of the pressure measurement method are verified by two groups of comparative tests. This pressure measurement method can be used to deeply study the relationship between arc pressure and arcing process. After that, four sets of breaking tests with same circuit parameters but different arc ignition currents are designed to simulate the breaking tests with different arc pressures, record the test parameters, fit the arc conductivity, and analyze the arcing process by stages. The results show that there is an obvious mapping relationship between the arc pressure and the arcing power in each test set, and the arc pressure has different effects on the arcing process in each arcing stage. Under the same arc power density, the arc conductivity exhibits propotional relationship the arc pressure.关键词：DC fuse;pressure measurement method;pressure characteristics;arc conductivity;arcing process14|13|0更新时间：2026-06-10
- 摘要：The safe and stable operation of electrical equipment in indoor substation is affected by the operating environment temperature. Optimization is carried out on the louver air inlet in the“ mechanical exhaust+louver air intake”ventilation and the heat dissipation mode, aiming to improve the airflow organization distribution, enhance ventilation and heat dissipation efficiency, as well as equipment operational efficiency. First, with the capacitor compartment as the research object, the simulation model of the related equipment of the capacitor compartment and the indoor environment is set up, the grid convergence index (GCI) is used to verify the independence of the grid model, and the accuracy of the simulation results is verified by fitting the measured and simulation data.Then, the scheme configuration and numerical simulation of the louvers aspect ratio (0.4, 0.8, 1.6) and the louvers tilt angle (±60°, ±45°, ±30°, ±0°) of the capacitor compartment are performed by the control variable method.Finally, with the lowest temperature in the operating area of electrical equipment as the target, the louvers intake design parameters is optimized and analyzed. The research results show that the best scheme is the configuration scheme of louvers width ratio 0.8 and louvers tilt angle-45°. The average temperature in the operating area of electrical equip ment is 34.9℃, the average flow rate is 0.47 m/s, and the average temperature decreases by 23.8% and the average flow rate increases by 5.4 times compared to the original scheme.The airflow distribution is improved by matching the louwer aspect ratio and tilt angle with the external dimensions of the electrical equipment. The optimization effectively reduces the temperature inside the capacitor compartment and provides a reference for the optimized design of ventilation and heat dissipation system for indoor substation.关键词：indoor substation;operating environment;measurement and numerical simulation;louvers;optimized design13|11|0更新时间：2026-06-10
- 摘要：For improving the efficiency of energy storage and battery swapping cabinet management strategy and promote its efficient utilization, a multi-objective power allocation energy management strategy based on artificial fish swarm algorithm is proposed. First, the system model of the battery swapping cabinet is set up. Then, the multiobjective power allocation mathematical model considering the battery power and the operating cost of the energy storage and battery swapping cabinet is set up. After that, the artificial fish group algorithm with such advantages as fast convergence speed and high efficiency is used to solve the model. It is shown by simulation that this strategy can achieve power distribution of the energy storage and battery swapping cabinet, reduce operation cost and improve operation efficiency.关键词：energy storage battery swapping cabinet;power distribution strategy;artificial fish swarm algorithm;multi-objective mathematical model21|14|0更新时间：2026-06-10
Technical Discussion
- Technical support is provided by Beijing Founder electronics co., LTD 陕ICP备05005324号-4
陕公网安备 61010402000197 - It is recommended to read the content of this site in Chrome&IE9+. Please switch to extreme mode in browser 360.
- Cookies We use cookies to help provide and enhance our service and tailor content. By continuing, you agree to the use of cookies.
0