High Voltage Circuit Breaker Research Articles

High anti-arc erosion performance of the Al2O3 reinforced Cu@W composites for high voltage circuit-breaker contacts

High voltage circuit-breakers with superior performance are demanded as the transmission distance extends and voltage rises, which are often subject to high current and voltage surges. Commercial circuit-breaker contacts are conventionally manufactured with CuW alloy by infiltration method, limiting their performance improvement in withstanding current (or voltage) and lifespan. In this paper, we optimize the microstructure and component of Al2O3 reinforced Cu@W80 composites (Al2O3/Cu@W80), which fabricates the Cu@W powder first by chemical coating and the composites by spark plasma sintering (SPS) method. The composites exhibit enhanced hardness (maximum value up to 273 HV) due to the addition of Al2O3 powder and a more homogeneous and refined tungsten phase compared to the CuW counterpart. Moreover, the dispersed Al2O3 particles with low work function become the preferred ablation phase and guide the electrical arcs, further improving the anti-arc erosion performance of Al2O3/Cu@W80. Our findings suggest that the Al2O3/Cu@W80 composite with optimized components could be potentially used as a candidate for high-voltage circuit-breaker contacts.

A Contribution to the Development of High-Voltage dc Circuit Breaker Technologies: A Review of New Considerations

To promote the integration of renewable energy resources into modern energy systems, high-voltage dc (HVdc) and circuit breaker (CB) technologies have become critical to achieving secure and efficient energy transmission. This article reviews the technical development of the related areas, compares diverse breaker concepts and topologies, investigates possible coordination and testing solutions, and points out the remaining challenges as well as future needs. The time-domain simulation and comparative analysis are adopted in this article to analyze and compare the performances of different HVdc CBs. By making use of different selectivity levels of multiterminal HVdc (MTdc) grids, the suitable planning and placement of HVdc CBs can be conducted. Furthermore, by providing insights into the performance of HVdc CBs, the work presented in this article can serve as a useful asset for the upcoming standardization and industrial application process of HVdc grid and CB design and testing.

Fault diagnosis of high voltage circuit breaker based on multi-sensor information fusion with training weights

To achieve more accurate identification of mechanical faults for high voltage circuit breaker (HVCB) with higher speed, multi-sensor information fusion has been proposed in this paper. The wavelet packet decomposition is used to decompose the signals collected by various sensors. Then, the energy of the wavelet packets in different frequency band can be obtained to constitute eigenvectors. After that, Dempster/Shafer (D-S) evidence theory can be applied for fault identification, where neural networks are built to train the weight of sensors without prior information. The conflicts existing in information fusion can be solved and the accuracy of fault diagnosis is improved. Finally, experimental validation is carried out to show the effectiveness of the proposed fault diagnosis strategy for the HVCB.

A novel multi-information decision fusion based on improved random forests in HVCB fault detection application

Evaluating the mechanical state of high-voltage circuit breakers (HVCBs) based on vibration information has currently become an important research direction. In contrast to the unicity of the travel–time and current–time curves, the vibration information from the different positions is diverse. These differences are often overlooked in HVCB fault identification applications. Additionally, the fault recognition results based on different location information often vary, and conflicting diagnosis results directly cause the accurate identification of the fault type to fail. Therefore, in this paper, a novel multi-information decision fusion approach is proposed based on the improved random forest (RF) and Dempster-Shafer evidence theory. In the proposed method, the diagnostic distribution of all classification regression trees in the RF is considered to solve the conflicts among the multi-information diagnosis results. Experimental results show that the proposed method eases the contradiction of multi-position diagnostic results and improves the accuracy of fault identification. Furthermore, compared to the common classifiers and probability generation methods, the effectiveness and superiority of the proposed method are verified.

Spectral and spatial characteristic behaviour of three-dimensional radiation transfer in SF6 switching arcs

The spectral and spatial characteristics of three-dimensional radiation transfer across an arc column of 0.08 m long, typical in high-voltage gas blast circuit breakers, has been studied in detail. The arc column under study corresponds to an instantaneous current of 15 kA in SF6 gas at a pressure of 10 bar. Our results show that to calculate the radiative flux divergence (as a volumetric energy source), only a segment of the arc column of 0.024 m in thickness needs to be considered to attain an accuracy of better than 90%. Photons with a frequency lower than 2 × 1015 Hz (150 nm in wavelength) can travel a considerable distance (>0.02 m) with an intensity attenuation factor of 0.2–0.8. Above 2 × 1015 Hz, only photons from the continuum spectrum can travel up to 0.015 m and line emission is absorbed within a distance of typically 0.0005 m, i.e. the arcing gas is optically thick to these photons. The gas within a cross-section of the arc column can be divided into a net emission core and a net absorption zone. The 55%–75% of the radiation emitted from the core is reabsorbed. The starting position of the net absorption zone sits within the temperature interval of 75%–80% of the maximum temperature on the axis. The quantitative information from this work is expected to serve as baseline data for developing improved approximate models for radiation transfer calculation in SF6 switching arcs.

Study on insulation performance optimization of EMU high-voltage equipment box

The EMU high-voltage electrical equipment on the roof not only bears the erosion of various harsh and extreme environments, but also bears the impact of various over-voltage, and the insulation performance of the electrical equipment on the roof is seriously threatened. This paper studies the insulation optimization design method of EMU high-voltage electrical equipment, puts forward the method of adding a certain length of insulating sheath on the electrical equipment to improve the insulation performance of high-voltage equipment box, and tests the insulation optimization measures on high-voltage circuit breaker and EMU high-voltage cable. The result shows that the installation of insulating sheath is feasible to improve the insulation performance of EMU high-voltage equipment box.

Real-Time Monitoring of High Voltage Switch Based on CAD

In the process of online real-time monitoring of intelligent digital filter high-voltage switchgear, the mechanical state diagnosis of high-voltage circuit breaker is based on fully understanding the mechanical characteristics of each component of circuit breaker. In this paper, K-means clustering algorithm is applied to the mechanical state detection of digital filter high-voltage switchgear. The mechanical state of the digital filter high-voltage switchgear is monitored in real time by using 126 kV GIS. Through fault simulation experiment and mechanical stability experiment, the corresponding changes of characteristics of each mechanical component of circuit breaker in signal waveform and corresponding data changes are found. The experimental results show that this method has good running speed and stability and is more suitable for the real-time monitoring of intelligent digital filter high-voltage switchgear.

Electrodynamic Forces in a High Voltage Circuit Breakers With Tulip Contact System—FEM Simulations

Paper concerns the effects of electrodynamic forces that act on the contacts of the tulip contact system that is often implemented in high voltage circuit breakers. The high voltage circuit breaker often consists of two such systems. One of the systems is treated as an arcing one - made of tungsten coated elements. Capable of implementing the phenomenon of thermal-expansion. The second is made of one or two crown laces. The first system consists of a single piece of large mass, cut in such a way as to obtain the effect of increasing the contact surface. The second is a system, often of several dozen contacts, so as to increase the contact area and reduce the transition resistance. The main problem of actual validation through dynamic measurements (electrodynamic forces) is the specificity of the circuit breaker operation. The contact system is located directly in the switch chamber filled with CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> or SF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> gas. Hence, tests under normal working conditions are very difficult - even impossible. Therefore, the authors proposed employment of FEM (Finite Element Method) in order to obtain values of electrodynamic forces acting on the contact system by executing the detailed 3D coupled simulation. The analysis of the results brought interesting conclusions that concerned operation of such contact layouts in short circuit conditions.

Hardware Design of Online Monitoring Device for the High-voltage Vacuum Circuit Breaker

In order to monitor the mechanical structure status of high-voltage vacuum circuit breakers in real time and diagnose faults online, a hardware design scheme of an online monitoring device for 10kV vacuum circuit breakers is proposed in this paper. From the perspective of practical application, this design scheme fully considers the practical working conditions of the monitoring device. The device not only monitors the mechanical vibration of the circuit breaker, the rotation stroke of the spindle and the position signal of the mechanical switch, but also monitors both the voltage and current of the opening (closing) coil, the energy storage motor and the closing lock coil. In this paper, in order to adapt the monitoring device to the actual application conditions, a modular design is adopted, the isolation and protection performance of the ports is strengthened and the integration degree of the device is increased.

Design and Analysis of a Novel HVDC Circuit Breaker Test Bench Based on an H-Bridge Cell MMCC

This paper proposes a novel circuit configuration for a high-voltage direct-current circuit breaker (HVDCCB) test bench that differs significantly from conventional test benches. The proposed test bench consists of a modular multilevel cascaded converter (MMCC) that is based on H-bridge cells, an output inductor, and an auxiliary capacitor bank. The proposed test bench is capable of generating controllable output currents up to several kiloamperes and output voltages up to several hundred kilovolts because each MMCC cell is operated by phase-shifted pulse-width-modulated (PSPWM) signals. Consequently, the proposed test bench can simulate a wide range of fault conditions within hardware limitations to test different HVDCCB types with various current and voltage ratings. The flexibility of the proposed test bench is complemented by a longer service lifetime with inherent circuit protection in the case of operational failure of the HVDCCB. The concept of the proposed test bench is verified experimentally on a downscaled test bench that consists of nine H-bridge cells and operates at an equivalent switching frequency of 92.5 kHz.

Comparative Feasibility Studies of High Voltage Circuit Breaker Operating in the LFAC System With Different Frequencies

With the development of the flexible low frequency transmission technology following the improvement of offshore wind power transmission, it is of great significance to investigate the operation adaptability of the main equipment especially under the low frequency conditions. A comparative study was performed in the present work to discuss the dynamic operation performance of a 252 kV/50 kA puffer-type circuit breaker influenced by the system operational frequency. Since the decreased operational frequency would result in a longer arc duration, a pre-designed driving mechanism with characteristics of high speed control was proposed and compared with a conventional unit. Moreover, as one of the reasonable indicators to evaluate the interruption performance of the circuit breaker, the critical rate of rise of recovery voltage (RRRV) that the circuit breaker can withstand after the arc extinguishment under different low frequencies were computationally obtained by an established arc model. The effects of the frequency change on the arc dynamic characteristics during the interruption of circuit breaker were comprehensively discussed as well and it could reasonably provide technical optimisation for the development of low-frequency-based circuit breaker for further engineering applications by analysing its interruption feasibility.

Оценка надежности выключателей в схемах распределительных устройств с различной топологией

The article discusses issues related to assessing the reliability of high-voltage circuit breakers in switchgear schemes with different topology of their design. A generalized formula is presented, using which it is possible to carry out calculations and further assessment of the failure flow parameter versus the switchgear scheme in which the circuit breaker is installed. To identify topological features, the standard switchgear schemes presented in the regulatory documents are analyzed. Five main types of circuit topologies and types of circuit breakers have been identified depending on the type of switched connections. For carrying out comparative calculations, one typical option was selected for each type of circuit topology. The distribution of circuit breakers by types in these schemes is presented. Calculations of the circuit breaker failure rates in schemes with the same initial data and with breaking down by types are carried out. Conclusions on the extent to which various types of schemes influence the reliability of high-voltage circuit breakers both as a whole and separately, depending on the type of switched connection are presented.

Design and Research of Operating Repulsion Mechanism Suitable for 252kV High-Speed Breaking Circuit Breaker

This paper proposes a high-speed operating repulsive force mechanism suitable for 252kV high-voltage circuit breakers. The mechanism draws on the working principle of the electromagnetic repulsion operating mechanism of the medium voltage circuit breaker, and combines the new electromagnetic fast repulsion device with the traditional disc spring hydraulic mechanism to realize the fast action of the circuit breaker. This paper first introduces the working principle of the electromagnetic repulsion operating mechanism, and proposes the initial design scheme of the mechanism. Subsequently, the digital twin technology was used to establish the rigid-flexible coupling multi-body dynamics model of the mechanism, and the defects of the initial scheme were analyzed based on simulation. Finally, the paper optimized the design of the initial scheme and verified it by simulation. The test shows that the 252kV high-voltage circuit breaker with the improved scheme as the operating mechanism works normally and can complete the fault breaking within 20.1ms, which is twice as fast as the current products of the same type.

A general model, estimation, and procedure for modeling recurrent failure process of high-voltage circuit breakers considering multivariate impacts

The high-voltage circuit breaker (HV CB) constitutes an important repairable asset in power systems. Due to its great number in the power network and strategic role in the successful operation of power systems, it is important to ensure its reliability. This paper deals with the estimation of the failure process of CBs considering the impact of age, operation intensity, corrective maintenance, and examination. A general model that integrates the above factors' effects is proposed, which can be reduced to many specific models like virtual age models, scale models, the two combinations, and their regression analysis. The model estimation under the condition of random censoring population data is illustrated, including parameters, reliability indicators, the cumulative intensity function, and goodness-of-fit tests. Moreover, a general procedure to stepwise select valuable effect functions into the general model is presented, thereby obtaining a specific formulation fitting the given data. The above works are applied to a real case to discuss the most probable failure process of the given HV CBs.

Test method for opening and closing time of 500kV high voltage circuit breaker under double terminal grounding condition

The opening and closing time test of 500kV high voltage circuit breaker can evaluate the mechanical characteristics and three-phase synchronization performance of the circuit breaker. Due to the influence of the earth resistance circuit, the traditional test method of circuit breaker opening and closing time can not be carried out when both ends are grounded. This paper first introduces the differential coil used to collect the signal, and then according to the requirements of field test, puts forward a test method for the opening and closing time of circuit breaker under the condition of double terminal grounding, and gives the basis for judging the opening and closing signal time. Finally, it compares and analyses the results of this method with the traditional high voltage circuit breaker opening and closing time test method, and obtains the conclusion of high voltage circuit breaker. The test method of grounding time division and closing time at both ends of the circuit breaker can fully meet the needs of field maintenance, which provides a new idea for the opening and closing time test of 500kV high voltage circuit breaker.

New Topology of Multi-port High-Voltage DC Circuit Breaker with Current-Limiting Function

New Topology of Multi-port High-Voltage DC Circuit Breaker with Current-Limiting Function

Mechanical Fault Diagnosis of High Voltage Circuit Breaker based on Improved GSO-SVM Algorithm

The vibration signal generated by the transmission and impact of mechanical components of circuit breaker has chaotic performances, which is difficult to be analysed by conventional signal processing methods. The phase space reconstruction of vibration signal is worked on, and the signal reconstruction parameters are calculated by mutual information method and Cao algorithm respectively. The vibration signal is reconstructed into a high-dimensional space, and its permutation entropy is calculated as a feature vector. Support vector machine (SVM) is used to identify the failure type of circuit breaker, and PSO improved GSA hybrid algorithm is used to optimize the parameters of SVM so as to obtain high recognition accuracy. The experiment is carried out with the measured vibration signal of the typical operation state of the circuit breaker. The results show that the characteristics of circuit breaker vibration signals can be extracted accurately with the combination of phase space reconstruction and permutation entropy. By using PSO-GSA-SVM, the fault types of circuit breakers can be identified quickly and effectively, and the problems of path distortion, energy leakage and mode overlap of existing diagnosis methods can be solved.

Arc and Fluid Dynamics Simulation for High-Voltage Circuit Breakers as a Design Tool

Arc and Fluid Dynamics Simulation for High-Voltage Circuit Breakers as a Design Tool

Arc Ablation Resistance and Dielectric Strength Properties of PTFE/BN Composites

The substantial improvements in transmission voltage, which have been adopted to meet fast-growing energy demands, require more reliable power equipment and higher-quality insulating materials. The polytetrafluoroethylene (PTFE) nozzle, as the key part of a high-voltage circuit breaker, is often subjected to arc ablation and breakdown phenomena. Thus, it is very urgent to develop nozzles with better performance. In this study, PTFE/boron nitride (BN) composites were prepared. The relationships among the BN filler loading, thermal transition properties, spectral reflectance properties, arc ablation resistance, and AC dielectric breakdown performances, as well as their corresponding mechanisms, were studied. Experimental results show that the thermal conductivity and thermal diffusivity of PTFE/BN composites increased monotonously with BN loading, and that both parameters were improved by 41% and 44%, respectively, for 11 wt % composites compared with pure PTFE. Moreover, PTFE/BN composites had higher light reflectance in the wavelength range from 320 to 2500 nm. The PTFE/BN composites presented better arc ablation resistance performance with increased BN loading, which was improved by 88.5%. It is thought that the increased thermal conductivity, thermal diffusivity, the strong light reflectance, and surface sediment after arc ablation contribute to the improvement in arc ablation resistance performance. The AC breakdown strength of PTFE/BN composites was enhanced by 30.93%, attributed to the good heat dissipation properties introduced by the BN fillers. Thus, filling BN into the PTFE matrix would be helpful to solve the equipment issue that comes from the improvement in transmission voltage.

High Voltage Circuit Breaker Vibration Signature Indices Evaluation for Condition Assessment

Abstract The importance of the high voltage circuit breaker for the power system’s safe and reliable operation is paramount. This research aims to analyse and provide the most significant high voltage circuit breaker health state indices based on the non-invasive vibration fingerprint measurement method. Results obtained and presented in this paper are validated on the data set acquired from the vacuum circuit breaker.