In the grid-connected inverter, both PLL (phase-locked loop) and DVL (DC-voltage can lead to frequency coupling in weak grid. Instabilities caused by have been widely discussed. For DVL, past studies analyzed effect of parameters on degree coupling, but it is quite unclear how affect inverter stability be designed under Hence, fully considering abovementioned an accurate admittance model PV (photovoltaic) established this study. By deriving modified matrix, effects grid impedance are clearly...

Based on Gap statistic model and relative entropy theory, a new edge detecting algorithm is presented in this paper. Firstly, to get the membership functions, dimensional various plane established by calculating value per pixel. Then, according coefficient decision threshold obtained. Finally, using criterion function plane, information extracted. Experimental results indicate that, compared with classical Sobel operator, proposed not only efficient extracting but also better de-noising performance.

Voltage flicker of PV plants due to the illumination condition is widely discussed. This paper introduced a assessment method for considering variation. By wavelet transform method, classified into four typical type. The inverter tested under these and station model are built on simulation platform. Then PCC simulated. Using statically weights type calculated from historical data. results condition, an area's given. In this paper, evaluation process certain reference value photovoltaic power station.

In conventional cumulant method of probabilistic load flow (PLF), random generator outages are usually simulated by discrete distributions nodal power injections, but that will lead to significant error in AC model. An improved PLF base on model is proposed this paper, which considers and loads uncertainties. Cumulant Gram-Charlier series expansion were applied deal with the variations loads, instead convolution calculations. According characteristics focused aspects grid, certain generators...

Due to the distinguishing features of periodicity, intermittent and fluctuant, power quality issue photovoltaic (PV) generation has been a hot topic. PV inverter is core component PVplant which determines system. Since output characteristics harmonic currents associated with variety factors (inverter topologies, testing conditions, modulation strategy, etc.), test results plants show randomness some extent. In this paper, new analysis method based on distribution fitting put forward describe...

To study the combination principles of structural design and material in asphalt pavement with semi-rigid bases, software BISAR3.0 was used to analyze load responses two layers base courses, its inversed structure. Then composite beam specimens composed kinds cement-treated macadam different cement contents were then fabricated, four-point bending strength fatigue tests conducted. Results indicated that lower layer (lower base) undertakes greater tensile stress than upper (upper base), life...

With the rapid development of wind power, electric grid faces significant challenges from variable nature and anti-peak-regulation characteristic power. In order to mitigate impact large capacity electrochemical energy storage is proposed solve this problem. This study establishes a unit commitment (UC) model with given specific characteristics. Meanwhile, forecast deviation curtailment are considered. Case studies modified IEEE 39-bus system employed validate method. The on economics, peak...

Abstract DC microgrids with high-proportion renewable generation have been popular in the new era of energy revolution. To improve fault ride-through capability microgrid, a scheme based on battery storage is proposed. A feed-forward term nonlinear disturbance observer introduced, and control strategy under improved droop designed for which can effectively suppress voltage fluctuations, shorten recovery time, thereby realizing microgrid short-circuit branch. Finally, model established...

At present, the grid-connected performance of renewable power stations at home and abroad is evaluated by means modeling simulation, influence each component model on evaluation can not be ignored. In station, accuracy photovoltaic inverters wind converters based test data full-condition type, but dynamic reactive compensation device carry out type because its high voltage level large capacity, so verification carried accordingly. this paper, a method static var generator (SVG)...

As the penetration rate of new energy increases, interactions between power stations and grid are becoming stronger. GB 38755-2019 "Code on security stability for system" clarifies requirements photovoltaic generation from perspective systems. Accurate station models basis conducting connection analysis, have significant practical applications analyzing access to Currently, electromechanical transient model parameters inverters obtained based laboratory parameter test data, without...

The virtual synchronous generator (VSG) which can emulate the typical (SG) dynamic has been used to improve performance and stability of inverter-based resources (IBRs). However, VSG encounter large-disturbance instability during grid voltage fluctuations or faults. During transient, power angle may overshoot even diverge due poor damping, still lose synchronization with become unstable if transient damping is insufficient, despite existence equilibrium points. Hence, it vital importance...