The weight of PV (photovoltaic) output characteristic index is constructed based on entropy weight method, and the typical scenarios are generated by AP (adaptive clustering) lustering algorithm. Considering the timespace distribution characteristics of EV (ectric vehicle) oad and demand response ability, the load linkage timespace response model is established. Based on the optimization of charging sequence and spatial layout of EV, the multiobjective planning method for charging station/PV station is proposed with meetting the distance constraints of charging stations and network constraints, which target the minimum annual total cost of charging station and the optimal index of user satisfaction. Case study, the integrated planning scheme of charging station/PV station is obtained based on the tradeoff between economy and satisfaction in each scenario.

For regional integrated energy system containing a high proportion of renewable energy, "quantity" and "quality" of energy are both discussed under "Exergy" concept and a twolayer optimization method considering exergy efficiency is proposed. Firstly, a model of multi – energy coupling of electricity, gas, heat and cold was established, and exergy analysis of energy and equipment is implemented. Then, a twolayer optimization model is established that considers system capacity planning and dispatching operation. The upper layer takes exergy efficiency and economy as the optimization goal for capacity allocation, while the lower layer takes the lowest operating cost as the optimization goal for unit output, therefore the best capacity allocation and operation scheduling scheme are obtained. Finally, a regional integrated energy system case is selected, and different schemes are analyzed for comparison. The result shows that the twolayer optimization method proposed in this paper can provide a better planning and scheduling scheme for the regional integrated energy system, while the exergy efficiency can characterize the actual level of energy utilization precisely and achieve highquality energy use.

Controlled islanding is an important measure to ensure the stability of power system and avoid largescale power outages. However, the traditional researches method that regard the splitting surface determination as a single objective optimization problem neglect the stability of isolated subsystem. Therefore, a control islanding strategy considering the stability of subsystem with new energy is proposed in this paper. Firstly, the initial islanding surface with the minimum powerflow disruption is obtained based on the electrical connections and power flow distribution between nodes. Then considering the electrical coupling connectivity of key nodes and the penetration of new energy, the final islanding surface is searched in the neighborhood search space of the initial solution, to improve the stability of the isolated network subsystem after splitting. Finally, the proposed method is analyzed based on the New England 39bus system, and the simulation results validate the effectiveness and advancement of the method.

Due to the high proportion of distributed photovoltaic access to the distribution network, the traditional centralized control is difficult to adapt to the voltage control problem in highdimensional environment. Therefore, this paper proposes a voltage coordinated control of photovoltaic distribution network with high proportion distribution considering network partition. Firstly, the distribution network is divided into centralized topology and local topology according to the partition function algorithm. Secondly, aiming at the centralized topology, the voltage centralized control model of distribution network based on second order cone programming (SOCP) is established with the minimum sum of voltage deviation and network loss as the objective function. Aiming at the local topology, the minimum node voltage deviation is taken as the objective function, and the voltage fine control model with Markov decision process is established. Then, the CPLEX solver and the deep deterministic gradient algorithm are used to solve the regional model effectively. Finally, the method is applied to an actual 35 kV/10 kV distribution network. The simulation results show that the proposed method has a good control effect, which ensures the safe operation of the distribution network and improves the photovoltaic penetration rate.

At the present stage, the construction and operation cost of optical storage DC microgrid is high and the lack of overall planning, so it is urgent to carry out the optimization planning research of optical hydrogen storage DC microgrid. Considering the fluctuation of photovoltaic power output power and the uncertainty of load change in light hydrogen storage DC microgrid, an optimization planning method of light hydrogen storage DC microgrid based on opportunity constraint is proposed. Based on the opportunity constraint planning, the optimization planning model of optical hydrogen storage DC microgrid with the lowest construction and operation cost is constructed, and the energy storage capacity configuration of the microgrid is optimized. Through the sequence operation, the constraints containing random variables in the model were used for deterministic transformation, and the CPLEX solver was called to solve the model. Through simulation calculation and analysis, the effectiveness and practicability of the optimization planning method of optical hydrogen storage DC micro grid based on the sequence operation algorithm were verified.

With the largescale access of new energy into the power grid, traditional power flow calculation can no longer meet the needs of the distribution network, and the effectiveness of reactive power allocation of the distribution network is reduced, thus affecting the safety and stability of the entire distribution network. Therefore, this paper analyzes the influence characteristics of power flow in substations including new energy stations, establishes the PCC node model of new energy stations connected to the regional power grid, and uses the branch forward pushback method as the power flow calculation method of distribution network. The characteristics of reactive power compensation in substation with new energy station access are analyzed, and the reactive power compensation capacitors are planned based on equal quantity grouping. Finally, taking a substation as an example, the feasibility of the proposed calculation method is verified, which fully proves the effectiveness of the proposed calculation method.

The bipolar plate is a crucial component of the proton exchange membrane fuel cell (PEMFC), with their performance playing a key role in the structural stability, long term durability, efficiency, and power density. Metal bipolar plates have attracted much attention due to their low cost, outstanding mechanical properties, and effective electrical and thermal conductivity. Among these materials, titanium possesses low density, excellent airtightness, high tensile strength, and exceptional corrosion resistance in acidic environments, which makes them highly promising for use in PEMFCs. However, the corrosion resistance, electrical conductivity, hydrophobicity, and heat and mass transfer properties of titanium bipolar plates are significantly influenced by the coating materials and forming methods. Therefore, this paper first introduce the functions and requirements of bipolar plates in PEMFC. It then reviews the main research findings from recent years regarding the coating materials and forming methods of titanium bipolar plates, and concludes with a discussion of future research directions.

Biomass pyrolysis can produce pyrolysis carbon and pyrolysis oil, of which the pyrolysis carbon is rich in surface functional groups and pore structures, while the pyrolysis oil contains a variety of components that can undergo redox reactions, which can be used for the preparation of fuel cell electrode materials and fuels, respectively. In this article, the working conditions of using wood pyrolysis oil as alkaline fuel cell fuel were optimized, and wood activated carbon (AC) and three types of wood pyrolysis carbon composite electrodes (AC/Fe, AC/Mn and AC/Fe/Mn) were prepared from wood pyrolysis carbon with K2CO3 activation and metal loading, furthermore the electrodes were analyzed using Fourier transform infrared spectroscopy, scanning electron microscopy, and electrochemical workstation. The microstructure, surface properties and electrochemical activity of the materials were analyzed by Fourier transform infrared spectroscopy and an electrochemical workstation. The results indicated that the optimal wood pyrolysis oil mass fraction and environmental temperature were 30% and 60 °C, respectively, when AC was used as the cathode electrode, at this point the current reached 3.10 mA; under the optimized conditions, the currents for AC/Fe, AC/Mn and AC/Fe/Mn were 8.02, 12.57, 15.25 mA, which were 159%, 305% and 392% higher than that of AC, respectively; under the optimized conditions, when AC/Fe/Mn was used as the cathode electrode and 12 mL of wood pyrolysis oil was added as the fuel, the fuel cell constructed from wood pyrolysis products could work continuously for 408.6 min with a total discharge capacity of 40.61 mAh.

To address the issues of restricted hydrolysis rate and low methane production in the anaerobic digestion of agricultural waste, zerovalent iron(ZVI) with different doses(4,8,12 mg/L) and particle size(microscale, nanoscale) was added during digestion after thermal pretreatment to investigate its enhancement of the codigestion of cow manure and corn straw. The research indicated that the appropriate addition of ZVI promoted both the hydrolysis acidification and methane production processes. The maximum cumulative methane yield was achieved with the addition of 8 g/L microscale ZVI or 4 g/L nanoscale ZVI, which increased by 20.7% and 29.5%, respectively compared with the control group. Microscale and nanoscale ZVI facilitated the release of dissolved organic compounds and the conversion of propionic acid to acetic acid. Nanoscale ZVI exhibited a stronger enhancement effect on hydrolysis and acidification than micronscale ZVI. However, excessive doses (8,12 g/L) of nanoscale ZVI had an adverse effect on methane production. ZVI promoted the enrichment of hydrolytic acidogenic bacteria and acetotrophic methanogens, such as Romboutsia, Saccharofermentans and Methanothrix, which enhanced the processes of hydrolysisacidification and methanogenesis.

The research develops a hybrid photovoltaic/thermallinked system with a heat pump and thermal energy storage in a single building, combining it with the idea of demandside management to solve the issue of excessive building energy consumption. To define its operational performance, a dynamic simulation model is created. After that, the configuration is optimized for demandside management, and the cost and energy use of various configurations are examined. The findings demonstrate that, as compared to the coupled system without storage, the ratio of feedin tariff to total generation for the heating and cooling seasons is improved by 23.96% and 7.07%, respectively. The demand for power rose sharply at night, rising by a total of 5.07% and 104.50%, and the system is capable of good power load management. The set point for the temperature of the water tank is 43 °C for the heating season and 24 °C for the cooling season, respectively. This configuration uses the least amount of energy overall among all optimized configurations, with a seasonwide energy savings rate of 41.77%, which is 7.10% higher than the rate without the use of management strategies. Approximately 50.9% and 72.7% of the total electricity used during the heating and cooling seasons is used during the storage period. To further lower the energy consumption of systems with control techniques and energysaving benefits, it is useful to research demandside management configuration optimization.