Real-time monitoring of aeolian vibrations is critical for the structural health of overhead transmission lines, yet achieving long-term, self-sustained sensing in high-voltage environments remains a persistent challenge. Herein, we report a fully autonomous, wireless vibration monitoring system driven by a dual-mode broadband triboelectric nanogenerator (TENG), which seamlessly integrates broadband energy harvesting, multi-parameter sensing, and wireless transmission. By coupling a freestanding layered structure with mechanical switching strategies and complementary dynamic configurations, the TENG achieves instantaneous discharge (ID) and continuous discharge (CD) modes with distinct sensing functionalities. The ID mode is used for frequency sensing with a response range of 5-88 Hz and an error of < 0.5 Hz, while the CD mode enables amplitude sensing with a linear response range of 0.1-4 mm, offering a linearity R2> 0.991 and a nonlinear error of delta< 3.59%. Beyond the device level, a customized low-loss power management module is developed to boost the charging rate by 7.96 times, successfully driving Bluetooth and infrared communication modules. Significantly, the system was deployed on a live 110 kV transmission line for field testing, demonstrating stable, continuous operation under varying environmental conditions. This work bridges the gap between laboratory-scale TENG innovation and deployable, industrial-relevant high-voltage monitoring systems.

A key challenge for multi-break vacuum circuit breakers (VCBs) in gas-insulated switchgear (GIS) is the design of compact voltage grading solutions for vacuum interrupters (VIs). This paper addresses the non-uniform voltage distribution across VI shields and series-connected breaks in VCBs that is caused by the significantly increased stray capacitances in GIS. To address these issues, we propose a novel self-voltage sharing capacitor pattern (SSCP), and the equivalent circuit of the VI with SSCP is analyzed. Simulations of the SSCP and the conventional grading capacitor pattern (CGCP) were conducted, and the maximum external electric field strength of the VI with SSCP was reduced by 53.6%, while the temperature rise was also decreased by 33.9%. A 40.5-kV VI prototype with SSCP was developed based on ring capacitors, external shields, and integrated encapsulation. Experimental results for series-connected VIs with SSCP demonstrate that the potential distributions among the shields and breaks approach the ideal values. The withstand voltage of series-connected VIs with SSCP is increased by 12.5%, and the temperature rise is decreased by 32.2%. The feasibility of the VI with SSCP has been verified, providing a compact voltage-sharing design reference for ultra-high-voltage multi-break VCBs in GIS.

Vacuum circuit interrupter as a kind of fluorine-free environmental protection switch is widely used in the field of power distribution, However, due to the saturation effect of long vacuum gaps, it is difficult to break through high voltage levels. To this end, this article proposes a high-voltage level main and auxiliary gap series integrated vacuum arc extinguishing chamber, where the auxiliary gap assists in insulation and arc extinguishing of the main gap. Based on the PIC-MCC (Particle In Cell Monte Carlo Collision) model, the dynamic dielectric recovery characteristics of the main and auxiliary gap series vacuum arc extinguishing chamber after arc are studied. The arc process is analyzed from the perspectives of arc current, arc electric field, sheath development, and particle transport dynamics, and the development laws of electrical parameters and microscopic particle motion processes are obtained. The results indicate that when the voltage division between the main and auxiliary gaps is 2:1, the electric field strength borne by the sheath during development is relatively small, with a maximum electric field strength of 7.12 × 105 V/m.At the same time, the voltage self-sharing can reduce the arc current, optimize the arc electric field distribution, and accelerate the development of the arc sheath layer. This article provides some guidance for the design of ultra-high voltage level vacuum arc extinguishing chambers.

Self-voltage sharing capacitor pattern (SSCP) could meet the compact uniform voltage distribution demand of tank multibreak vacuum circuit breakers (VCBs). However, the consistency analysis of postarc sheath evolution in series-connected breaks with grading capacitors has drawn little attention in previous studies. This article focused on the dynamic development of postarc currents in series-connected vacuum interrupters (VIs) with various grading capacitor patterns. The concept of series-connected sheath consistency was introduced to quantitatively characterize the postarc sheath enhancement effect in series-connected VIs with SSCP, and the particle-in-cell (PIC) computational model was established. Furthermore, the influence of series-connected breaks, shield potential, and contact distance on postarc sheath evolution was investigated, which indicated that SSCP could affect the evolution process of postarc currents, sheath potential, and sheath thickness. Compared to conventional grading capacitor patterns (CGCPs), the postarc current peak was reduced by 20%. The maximum value of the consistency coefficient of SSCP is 0.20 (the ideal value is 0) in series-connected breaks. This article could be used for the evaluation of postarc sheath evolution consistency of series-connected SSCP, which promotes the advancement of ultrahigh-voltage multibreak tank VCBs.

Environment-friendly tank multibreak vacuum circuit breakers (TMVCBs) are a promising alternative to SF6 circuit breakers for high-voltage applications. However, the static and dynamic voltage distribution mechanisms among series-connected breaks in TMVCBs remain insufficiently understood. In this article, the static and dynamic voltage distribution characteristics of environment-friendly TMVCBs were investigated. A finite-element electric field model of environment-friendly TMVCBs was established to obtain the static voltage distribution among breaks, and the nonuniform static voltage distribution is discussed by solving the equivalent capacitance parameter matrix. Subsequently, the modified Langmuir postarc current model was proposed, and the influence of the main shield on the postarc current of vacuum interrupters under a tank structure was analyzed, which demonstrated the dynamic voltage distribution mechanism of TMVCBs. Based on the voltage distribution analysis and a grading capacitor comparison, the interruption tests of a 126-kV environment-friendly TMVCBs were conducted to validate the proposed static and dynamic voltage distribution mechanisms, which also provided the guidance for the grading capacitor design of TMVCBs at ultrahigh voltage and extrahigh voltage levels.

The vacuum interrupter of transmission grade is an urgent industry-level problem to be solved, the requirements for insulation and current-flow capacity become more stringent under high voltage and high current conditions. The high-voltage vacuum interrupter integrated with main and auxiliary gaps in series is expected to become a new solution for achieving 252 kV and above voltage levels. By utilizing the auxiliary gap to assist the main gap insulation and arc extinguishing, it overcomes the insulation bottleneck of long vacuum gaps. However, its temperature rise characteristics under high current conditions remain to be studied. This paper establishes a model of vacuum interrupter integrated with main and auxiliary gaps in series. Based on heat transfer theory, a thermal network model of the vacuum interrupter integrated with main and auxiliary gaps in series is developed to analyze and calculate its heat dissipation process. According to the computational results, a structural optimization method is proposed—employing a heat-dissipating shield—to improve the temperature rise of the vacuum interrupter, followed by simulation validation. The study indicates that the new structure of the high-voltage VI integrated with main and auxiliary gaps in series can meet the insulation requirements for high-voltage-level VIs. With the heat-dissipating shield, the maximum temperature rise inside the VI is 68 K, representing a 17

Vacuum degree is a key parameter determining the breaking and insulation performance of vacuum circuit breakers (VCBs). Its deterioration over time can lead to performance failure. Therefore, achieving high-precision online monitoring of the vacuum degree is essential for ensuring the operational reliability of VCBs. This study employs electromagnetic radiation waves generated by vacuum discharge as indirect indicators of vacuum degree and investigates their physical mechanism and detectable lower limits under different conditions. On this basis, a classification model integrating temporal convolutional network (TCN), bidirectional gated recurrent unit (BiGRU), and an attention mechanism is developed to learn discharge event features from the waveforms and classify internal pressure states. Experimental results show that the method supports vacuum degree monitoring from 1.0 x 10(-3) to 10 Pa, achieves 92% precision, and outperforms support vector machine (SVM), kernel extreme learning machine (KELM), and back propagation neural network (BP-NN). This approach provides a practical and efficient solution for real-time condition monitoring of VCBs.

Due to the absence of the natural current zero-crossing point in the dc system, how to realize the dc rapid interruption has been a critical issue. A DC transfer switch of passive self-excited oscillation based on vacuum and nitrogen-hydrogen mixed gas series linkage is proposed in this paper, and the ability of the high arc voltage switch to quickly interrupt current is analyzed. When the arc voltage is increased to 300 V, the breaking time of small current 2 kA is reduced by 61.69

The inherent non-stationarity, weak periodicity, and abrupt transient mutations of wind turbine gearbox vibration signals present substantial challenges to traditional diagnostic frameworks. To improve diagnostic accuracy, this paper proposes a fault diagnosis method for wind turbine gearboxes based on the Snake Bird Optimization Algorithm (SBOA)-optimized Variational Mode Decomposition (VMD) and an improved Bidirectional Gated Recurrent Unit (BiGRU). First, SBOA is employed to adaptively optimize the number of modes and the penalty factor in VMD, enhancing the effectiveness of signal decomposition. Second, an improved BiGRU model is constructed, featuring a three-channel BiGRU architecture, along with the introduction of periodic skip connections, a temporal attention mechanism, and a time-decay loss function to strengthen the extraction and fusion of temporal features. Finally, a Softmax classifier is used to achieve precise identification of fault types. Experimental results demonstrate that the proposed method achieves an average accuracy of 99.40% in diagnosing five types of faults, significantly outperforming comparative methods. Ablation studies further validate the effectiveness of each improved module. The proposed method provides reliable technical support for the intelligent operation and maintenance of wind turbine gearboxes.

To extract the accurate junction temperature (T-temp) of a single high power press pack thyristor, a novel online monitoring method is proposed in this article. By collecting gate cathode voltage in real time, the system obtains more accurate junction temperature of thyristor. The feasibility of gate cathode voltage (V-GK) as a junction temperature parameter is deduced by numerical model theory. A simulation model is constructed in technology computer aided design (TCAD) to verify the conclusion that there is a negative temperature coefficient between the V-GK and the T-temp. Based on this, preliminary tests from a developed online measurement system are presented. The gate drive circuit and junction temperature measurement circuit have been integrated in the design. The entire online monitoring system enables real time and accurate online measurement of the gate cathode voltage with the error of less than 2.3%. Moreover, comparing with thermocouple and thermal model methods, the junction temperature error value do not exceed 5 degrees C. This provides strong technical support for accurate junction temperature online monitoring.

High-voltage vacuum circuit breakers (VCBs) are a crucial approach to the environment-friendly replacement of SF6 in power switchgear. However, the nonuniform voltage distribution of the multiple floating shields (MFSs) in high-voltage vacuum interrupter (VI) has hindered their development. In this article, we propose a new "self-voltage sharing" mechanism for MFS of high-voltage VCBs in series-connected gas-insulated switchgear (GIS). To analyze the mechanism of self-voltage sharing, a new self-voltage sharing capacitor pattern (SSCP) of high voltage VI is developed. The voltage distribution of MFS in conventional grading capacitor pattern (CGCP) and SSCP is calculated. The power frequency voltage distribution and voltage withstand test are conducted to verify the effectiveness of the self-voltage sharing mechanism. The results show that the SSCP can optimize the voltage distribution of the MFS in VI. When two 126 kV VIs are series-connected, the ring capacitor needs to be 4000 pF to meet the voltage distribution requirements of the MFS. When the grading capacitor reaches 4000 pF, the enhancement effect of SSCP is 9.4% compared with CGCP. This article aims to identify the voltage distribution mechanism and realize engineering application for double-break high voltage VCBs in GIS.

High voltage environment-friendly tank circuit breakers impose significant challenges on the internal and external insulation performance of vacuum interrupters, whereas vacuum interrupters adopting the self-voltage sharing design can meet the requirements for compact insulation and effective voltage sharing in tank circuit breakers. However, the surface flashover characteristics of self-voltage sharing vacuum interrupters have not been comprehensively investigated. In this paper, the surface flashover simulation model of vacuum interrupter is established, and the influence of self-voltage sharing regulation methods on surface flashover characteristics is analyzed. In addition, the surface flashover voltages of vacuum interrupter ceramic along gas/solid interface are obtained under various regulation methods through experimental device, and the streamer evolution is captured by a high-speed camera. The results show that the surface flashover voltage is increased by 18.8% with the self-voltage sharing regulation methods. Moreover, the surface flashover process and streamer evolution are discussed, which reveals the mechanism of enhancing surface flashover voltages of vacuum interrupters with the self-voltage sharing regulation methods. The results can provide a reference for optimizing the surface insulation performance of vacuum interrupters in environment-friendly gas insulation switchgear.

Vacuum circuit breaker is one of the mainstream directions to realize the environmental protection replacement of SF6 in high voltage power switch. However, there is a bottleneck of long gap insulation saturation in vacuum interrupter, which limits its development to higher voltage level. In this paper, a vacuum interrupter structure with integrated auxiliary gap and main gap is proposed, which is expected to achieve a breakthrough in the voltage level of 252 kV and above. Firstly, a new structure of high voltage vacuum interrupter with main and auxiliary gaps in series is designed, and the principle of asynchronous linkage between main and auxiliary gaps is analyzed. Secondly, a multi-dimensional coupling simulation method of transient electromagnetic field and multi-body dynamics which can fully reflect the dynamic characteristics of main and auxiliary gaps is proposed. Finally, the influence of relevant parameters of self-driven mechanism on the opening motion and collision characteristics of arc extinguishing unit is simulated and analyzed, and the selection design is carried out. The simulation results show that the opening displacement of the designed self-driving mechanism can reach 22.5 mm in 20 ms, and the peak value of the collision impact force is 42668 N when the opening is in place, which is 66.5

To enhance the natural commutation performance of medium-voltage hybrid DC circuit breakers (HDCCB), this paper proposes a novel topology for a high-arc-voltage HDCCB based on series dielectrics (HAV-HDCCB) and analyzes its operating principle concerning current transfer performance. A Simulink circuit model was developed to compare the overall interruption effectiveness between the proposed high-arc-voltage HDCCB and a conventional HDCCB. The results demonstrate a significant reduction in the current transfer time from 2320 μs to 273 μs. Furthermore, the influence of different arc voltages and the number of series/parallel power electronic devices in the transfer branch on the arc current transfer performance was investigated.

Environment-friendly tank vacuum circuit breakers utilizing vacuum interruption and environment-friendly gas insulation are considered an effective approach to replace SF6 circuit breakers. However, surface flashover along the gas–solid interface of the vacuum interrupter in dry air is one of the obstacles for expanding the application of tank vacuum circuit breakers. Thus, a simulation model of surface flashover along gas–solid interface of the vacuum interrupter is developed in this paper. The effects of two improving methods — installing the shielding and setting the main shield potential to 50

The contact magnetic fields of vacuum interrupter are crucial for the stable operation of vacuum circuit breakers (VCBs). However, little attention has been devoted to the influence of contact magnetic fields on the post-arc residual plasma dissipation process in previous study works. To investigate the impact of different magnetic field control on the post-arc residual plasma dissipation process, we proposed a novel probe diagnostic method and a magnetic field control device. A new experiment system for post-arc residual plasma probe diagnostic and external pulse magnetic field control circuit was established. Then, the new diagnostic method is applied to investigate the post-arc residual plasma dissipation process in radial magnetic field (RMF) and axial magnetic field (AMF) of VCBs. The evolution of the vacuum arc and the extinction locations of cathode spots were observed using a high-speed CMOS camera. This research shows that compared to RMF arc control, AMF exhibits a lower initial electron density (4.78 x 1010 cm-3) and a shorter electron density decay time (35 mu s). The results of this study agree with prior optical diagnostics and are consistent with the development trends of post-arc residual plasma. This paper can verify the diagnostic effects of the post-arc residual plasma in vacuum interrupter under magnetic field control. It provides a low-cost probe technique for diagnostic of post-arc residual plasma in VCBs.

Achieving compact design with high insulation performance is a critical challenge for vacuum interrupters (VIs) in eco-friendly gas-insulated switchgear (GIS). This article addresses the severe nonuniform of potential distribution across the multiple floating shields (MFSs) in VIs for GIS by proposing a novel self-voltage sharing capacitor pattern (SSCP), which integrates grading rings and ring capacitors on the exterior of the VI. The simulation results show that, compared with the conventional VI, the SSCP improves the potential distribution on the MFS by 21.64%, 13.07%, and 6.05%. Furthermore, it achieves a 24.60% reduction in the maximum internal electric field strength and a 35.21% reduction in the external field. To validate these findings, an experimental platform was established for a 145-kV VI. The experimental results regarding the influence of grading capacitance on potential distribution are consistent with the simulation trends. Specifically, with a grading capacitance of 2000 pF, the MFS potential distribution reaches 74.95% $U$ , 48.87% $U$ , and 22.63% $U$ , closely approximating the ideal linear distribution. This research provides a theoretical basis and an optimized structural design for enhancing the insulation performance of high-voltage VIs in GIS.

Non-uniform dynamic voltage distribution (DVD) across series-connected breaks is a critical factor limiting the development of multi-break vacuum circuit breakers (VCBs) towards higher voltage levels. However, the mechanism underlying the non-uniform DVD across the series-connected breaks remains unclear. An equivalent circuit model of double-break VI was proposed in this paper based on the post-arc plasma transport characteristics derived from Particle-in-Cell (PIC) method, considering the effects of charge collection of the shields and middle electrode. Based on the established model, the charge collection characteristics under varying initial plasma densities were investigated, yielding a quantitative relationship between the charge collection on the shields and middle electrode and the resulting DVD. The study reveals that non-uniform charge collection by the shields and the middle electrode alters the charge state of external grading capacitors, significantly affecting the DVD. Quantitative analysis indicates that at an initial plasma density of 1×1017 m-3, a 1000 pF grading capacitor reduces the voltage sharing non-uniformity to 9.4%. The accuracy of the model was validated by the strong consistency between simulation results and experimental measurements. This work provides a theoretical reference for research on the mechanism of series DVD in high-voltage vacuum switches.

With the proposal of carbon peak and carbon neutrality target, the tank multi-break vacuum circuit breakers with environment-friendly gas insulation is an effective methods to replace SF6 gas in the field of high voltage and ultra-high voltage. Firstly, the electric field simulation of tank multi-break vacuum circuit breakers is carried out. The scale test electrode is designed for the key position according to the electric field distribution, and the lightning breakdown test with different pressures, electrode distances and electrode structures are carried out. The results show that 0.9 MPa dry air and 0.9 MPa CO2 can satisfy the insulation configuration requirements of the tank multi-break vacuum circuit breaker. In addition, the surface flashover characteristics of the ceramic shell interface of vacuum interrupter are studied, the effects of gas pressure, metal particle attachment location on the surface flashover voltage of the ceramic shell are investigated, which provides guidance for the development of vacuum interrupters in ultra-high voltage field.

To meet the compact voltage-sharing configuration requirements of high-voltage multi-break tank vacuum circuit breakers, a simulation study on post-arc particles in a double-break series vacuum interrupter under main shield voltage-sharing was conducted. A PIC computational model for the post-arc phase in a double-break series vacuum interrupter under main shield voltage-sharing was established, revealing the variations in post-arc particles, post-arc potential, post-arc current, and post-arc sheath thickness. The study indicates that main shield voltage-sharing affects the development of the post-arc sheath in the double-break series main shield voltage-sharing vacuum interrupter. Compared to the traditional break voltage-sharing method, the main shield voltage-sharing method resulted in the smallest peak value of post-arc current (10 A) and the best consistency in sheath development between the series breaks (consistency coefficient approaching 0). This research provides valuable reference for the design of series main shield voltage-sharing vacuum interrupters in multi-break tank vacuum circuit breakers.