The characteristics of zero moment of inertia of modular multilevel converter, it can not support the frequency fluctuation of AC power grid, so that the overall inertia of AC/DC hybrid system decreases, affecting the dynamic performance and stability of the system. Therefore, an improved powervoltage droop control combined with a virtual synchronous machine technology of coordinated control strategy, in the case of de voltage stability of ac power grid frequency adjustment, at the same time, reasonable allocation of power between the converter, in the case of without communication system to establish effective energy management system. In order to verify the feasibility and effectiveness of the proposed control strategy, a comparative test was conducted with the traditional double closedloop control. The results show that the proposed control strategy effectively solves the dynamic performance and stability problems of the system caused by low inertia and under damping.

In the high wind and photovoltaic power penetration distribution network, under the influence of the control strategy for inverter, the fault current weakfeed characteristic is obvious, the traditional power frequency protection's operation performance is declining, and even cause unwanted operation or refuse operation. In this paper, the fault current characteristics of synchronous generator and inverter interfaced distributed generation power supply are analyzed, and it is found that there is an obvious difference between the fault current vectors on both sides of the distribution network during internal and external faults, and then the correlation coefficient is used to measure the vector correlation and construct the action criteria. Based on 5G communication technology, a new scheme of correlation pilot protection for high wind and photovoltaic power penetration distribution network is proposed. The simulation results show that the proposed protection scheme can identify the short circuit fault of high wind and photovoltaic power penetration distribution network quickly and stably, has a strong ability to withstand noise, and solves the influence of 5G time delay fluctuation on pilot protection.

Distributed energy storage technology can change the temporal and spatial distribution of energy and can improve the flexibility of the distribution network to integrate the distributed renewable energy. Under the traditional mode, the cost of energy storage is high, and the utilization rate of energy storage resources is low. Cloud energy storage is a new business model that can respond to the demand for distributed energy storage. Under the cloud mode, the virtual energy storage configuration model is built by considering the factors that affect the demand for virtual energy storage, such as load, the output of renewable energy, timeofuse electricity price, and cost. A community with 14 typical users is selected as a case to verify the validity of the model established above. Case analysis shows that, under the cloud mode, the virtual capacity and power demand of energy storage for users are 18.2% and 7.1% lower, the annual cost is 4.12% lower, and the utilization rate of energy storage is 8.12% higher than it under the traditional mode. Therefore, the cloud mode of energy storage has a good prospect in the application.

Aiming at the problem that the decisionmaking process in the existing power grid transmission line ice melting scheme arrangement takes a long time, and there is a risk of operation stability, which leads to the insufficient decisionmaking ability of the power grid to deal with severe ice disasters, a comprehensive energysupported transmission line ice melting optimization strategy under the dynamic constraints of stability risk is proposed. Firstly, an icing growth model is established based on meteorological data, the corresponding relationship between transmission line icing growth and line faults is analyzed, a line outage probability model is established, and the loss degree of line outage is quantified. Secondly, the mechanism of changing the line flow based on integrated energy to slow down the growth of line icing is analyzed, and the icemelting risk constraints of distribution lines based on integrated energy are considered to establish a line icemelting model based on integrated energy. On this basis, an icemelting optimization method for transmission lines with integrated energy support under the dynamic constraints of stability risk is proposed, which is iteratively solved based on the Lagrangian relaxation method. IEEE RTS79 is used to simulate the ice melting example. The results show that the method based on this paper can improve the efficiency of the transmission line ice melting scheme arrangement and ensure the safe and stable operation of the power grid.

Catalytic reforming of palm kernel shell (PKS) pyrolysis volatile matter was studied using char (Char) and activated carbon (AC) as catalysts under microwaveassisted heating. The impacts of different carbonbased catalysts on the composition of products were studied. The possible reaction pathways during catalytic reforming of PKS pyrolysis volatile matter under microwaveassisted heating were also investigated. During catalytic reforming of pyrolysis volatile matter, the catalyst promoted the yield of gas product, which led to the decrease of biooil yield. Compared with the Char, AC not only has higher catalytic activity to facilitate the conversion of biooil to gas, but also exhibited better selectivity for the formation of singlering aromatic compounds (especially phenol) in biooil. Using the AC catalyst, the concentrations of the singlering aromatic compounds reached 84.25%. The catalyst mainly promoted the secondary reactions such as demethoxylation reaction and dehydrocarbylation reaction.

Ammonia synthesis based on hydrogen derived from renewable electricity (i.e. green hydrogen and green ammonia process) is frequently fluctuated due to weather change and the sections are highly coupled. To understand the synthesis and scheduling of power generation and transmission, hydrogen production by water electrolysis, hydrogen storage, electrochemical energy storage, and ammonia synthesis sections in green ammonia process, a generic process model for both steadystate and dynamics mode was developed using the next generation process simulation software, AVEVA Process Simulation, and the dynamics response of the model to weather fluctuation was investigated by means of multisteady state simulation. The results show that optimized design and scheduling of the hydrogen storage and electricity storage modules can significantly stabilize the ammonia production, utilize excess renewable electricity, reduce grid power input, and thus, improve the economy.

Density functional theory calculations were employed to investigate the mechanisms and energy changes involved in C–C bond cracking, CH₄ reforming, and water gas shift reactions in the tar reforming process. The findings reveal that, in the CC bond cracking reaction, C₃H₈ initially adsorbs onto the catalyst surface to form adsorbed C₃H₈*, subsequently undergoing cleavage to produce CH₃* and CH₂CH₃*. While the cracking reaction is exothermic, it is hindered by a significant energy barrier and difficult to carry out. In the CH₄ reforming reaction, CH₄* undergoes sequential dehydrogenation reactions, producing CH₃*, CH₂*, and CH*. Comparatively, CH* has a greater tendency to react with OH* to form CHO*, which further undergoes dehydrogenation to form CO*. Additionally, H* generated in each step combines to form H₂*. Throughout the CH₄ reforming process, the ratelimiting step is the cracking of CH₂* to CH*. In the water gas shift reaction, the OH* species formed from H2O* decomposition prefers to combine with CO* to generate COOH* rather than directly reacting with H* to produce H₂*. COOH* removes H and generates COO*, which is the rate limiting step.

Citric acid is one of the most productive biomass organic acids in the world and has been widely used. In this paper, we used reduced iron powder as iron source, citric acid as multidentate ligand and carbon source, and used ammonia to enhance the coordination solubilization ability of citric acid to iron powder, so that it could quickly form a homogeneous complex solgel, which was then carbonized to obtain carboncoated coreshell ironbased FischerTropsch catalyst. In the performance test, the catalyst synthesized by direct dissolution of iron powder with citric acid exhibited remarkable catalytic activity and stability, giving the CO conversion of 99.2%, C5+ hydrocarbon selectivity of 53%, and the CO conversion activity was stably kept above 97.3% for a time on stream of 168 h. The citric acid coordination method is greener and safer, which avoid the use of iron salts such as ferric nitrate, and the risk of explosion and toxic gases in the reduction process of iron salts. This synthesis method provides a new idea for the green and safe production of catalysts.

In order to accurately predict the thermal and electrical performance of solar photovoltaic/thermal (PV/T) systems, this study utilized the Particle Swarm Optimization (PSO) algorithm to optimize the Radial Basis Function (RBF) neural network. Based on this method, a simulation prediction model for the performance of solar PV/T systems was established and compared with a prediction model based on an unoptimized RBF neural network. Additionally, this research built a solar PV/T experimental platform and collected experimental data using a cloud platform for the aforementioned model. The research results indicate that the RBF neural network model optimized using the PSO algorithm exhibits better prediction accuracy compared to the unoptimized RBF neural network model. The optimized RBF neural network model demonstrates a 20% improvement in prediction accuracy and a 30% increase in prediction stability compared to the unoptimized model. The goodness of fit, as indicated by the Rvalue, is also improved compared to the unoptimized model. The prediction model established based on the PSORBF neural network can accurately predict the thermal and electrical performance of solar PV/T systems.

The amount of solar radiation and wind load will directly affect the continuous generation of solar thermal power station. Therefore, according to the actual environmental conditions of Zhongdian Nao Maohu solar thermal Power Station in Hami region, Xinjiang, a threedimensional numerical model of heliostat group was established to simulate the heating conditions and flow field characteristics of the mirror group under solar radiation and upwind Angle in different seasons, and the distribution of mirror flares and pulsating wind pressure coefficients under different wind incidence angles were analyzed. The results show that the simulated drag coefficient and lift coefficient are in good agreement with the related research results, which verifies the validity of the model. The distribution of flares in different seasons is similar and mainly depends on the variation of solar direction Angle. With the increase of the wind incidence Angle, the wake region of the mirror cluster decreases first and then increases. Since the wake in the helioscope group can effectively inhibit wind pressure, the internal stability can be ensured by combining the arrangement of the group. Among them, the center of the regular pentagonal helioscope maintains a low pulsating wind pressure, which greatly improves the force balance of the mirror.