High voltage circuit breakers (HVCBs) in the gas insulated switch gear (GIS) play an important role in the control and protection of powersystem. The mechanical faults account for the largest part of common faults in...
详细信息
ISBN:
(数字)9798350355369
ISBN:
(纸本)9798350355376
High voltage circuit breakers (HVCBs) in the gas insulated switch gear (GIS) play an important role in the control and protection of powersystem. The mechanical faults account for the largest part of common faults in HVCBs. This paper establishes the rigid-flexible model of a 550 kV GIS HVCB, and experimentally studies the behavior characteristics of the HVCB under mechanical fault situation. Firstly, the fine 3D structure model of the 550 kV GIS HVCB is built and the arc-extinguishing principle of the HVCB is analyzed. Then, the rigid model and the rigid-flexible coupling model of the HVCB’s components and the whole system are established. The vibration signals of the two models are simulated and compared based on the finite element method. The component model mainly consists of the static arc contact and the dynamic arc contact. Furthermore, the mechanical fault is artificially set in the HVCB, and the vibration waveform are obtained. Finally, the simulation data is compared with the experimental results and the fault characteristics are analyzed. This research realizes the modeling, simulation and measurement of HVCB dynamic characteristics, which is of great significance to the diagnosis and prevention of HVCB mechanical faults.
The increasing integration of renewable energy reduces the inertia and frequency support capacity of the powersystem. The issue of frequency stability has become one of the core issues in the security and stability o...
详细信息
After the integration of large-scale Distributedgeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between powergeneration and de...
详细信息
After the integration of large-scale Distributedgeneration(DG)into the distribution network,the randomness and volatility of its output result in a reduction of spatiotemporal alignment between powergeneration and demand in the distribution network,exacerbating the phenomenon of wind and solar power *** a novel powersystem model,the fundamental concept of Regional Autonomous power Grids(RAPGs)is to achieve localized management and energy autonomy,thereby facilitating the effective consumption of ***,this paper proposes a distributed resource planning strategy that enhances the autonomy capabilities of regional power grids by considering multiple evaluation indexes for ***,a regional Energy Storage(ES)configuration strategy is *** strategy can select a suitable reference value for the upper limit of ES configuration based on the regional load andDGoutput to maximize the elimination of source load deviations in the region as the upper limit constraint of ES ***,a control strategy for regional ES is proposed,the charging and discharging reference line of ES is set,and multiple autonomy and economic indexes are used as objective functions to select different proportions of ES to control the distributed resources of the regional power grid and establish evaluation indexes of the internal regional generation and load power ratio,the proportion of power supply matching hours,new energy consumption rate and tie line power imbalance outside the region to evaluate changes in the regional autonomy *** final simulation results showthat in the real regional grid example,the planning method in the planning year in the region of the overall power supply matching hour ratio and new energy consumption rate increased by 3.9%and 4.8%on average,and the power imbalance of the tie line decreased by 7.8%on *** proposed planning approach enables the maximization of regional autonomy while effectively smoothing the fluct
Aiming at the increasing burden of powersystem peaking caused by the integration of large-scale new energy generation into the grid and the imperfect participation mechanisms for peaking entities in the power market,...
详细信息
Aiming at the problem of low-frequency oscillation when photovoltaic powergeneration is connected to weak AC system, a linearization model of photovoltaic powergeneration is established, which ignores current inner ...
详细信息
The two control objectives of voltage regulation and precise current sharing are conflicting in multi-bus DC microgrids. In this paper, a distributed control strategy is proposed, and it can achieve accurate current s...
详细信息
Compared to Si IGBTs, SiC MOSFETs can reduce switching losses, achieve higher switching frequencies and enable smaller converter size. However, due to the high dv/dt of SiC MOSFETs, certain topologies, such as two SiC...
Compared to Si IGBTs, SiC MOSFETs can reduce switching losses, achieve higher switching frequencies and enable smaller converter size. However, due to the high dv/dt of SiC MOSFETs, certain topologies, such as two SiC MOSFETs in a phase-leg configuration, are highly sensitive to crosstalk, which can slow down switching speed and even reduce gate oxide’s lifetime. In this paper, an accurate model of crosstalk is established by considering the impacts of both dv/dt and di/dt in the power loop. The proposed model can simulate the gate-source voltage on bare die of SiC MOSFETs, allowing for a more accurate evaluation of the impact of crosstalk. Model verification is implemented using a double pulse test (DPT) platform and a gate driver with active miller clamp technology. key parameters of the model are extracted from both 3D simulation models and measurement experiments. The DPT waveform of power loop is used as the excitation source in the simulation, and the simulated gate-source waveform shows good agreement with the experimental waveform. Based on the model, parameter sensitivity analysis is performed, and suggestions for improving crosstalk suppression are proposed.
In the new powersystem, the output of new energy power stations has strong volatility, which leads to huge deviation assessment expenditure. Therefore, based on the improved data preprocessing algorithm and deep lear...
In the new powersystem, the output of new energy power stations has strong volatility, which leads to huge deviation assessment expenditure. Therefore, based on the improved data preprocessing algorithm and deep learning algorithm, a day-ahead reporting strategy of wind power plants considering error prediction characteristics is proposed. Firstly, considering the historical real output and prediction error, the historical data is decomposed based on the complete noise-assisted ensemble empirical mode decomposition algorithm (CEEMDAN). Then, the components are introduced into the long short-term memory (LSTM) optimized by the improved particle swarm optimization algorithm (IPSO), and the components are reconstructed to obtain the original prediction curve and the error prediction curve. Finally, the empirical distribution function is used to revise the prediction error curve, and the original prediction curve and the error prediction curve are superimposed to obtain the final day-ahead report curve. The correctness and feasibility of the reporting strategy are verified by simulation analysis.
With the construction of new powersystem, high-capacity renewable energy sources including wind power are integrated into the powersystem, whose transient response characteristics have a significant impact on the sa...
详细信息
Microstrip antenna as a kind of receiver front-end equipment of microwave energy transmission system, which plays an important role on the overall transmission efficiency of the system. Conventional solid metal antenn...
详细信息
暂无评论