[Objective] In order to reduce total cost of energy consumption of commercials, meet the responsibility weight of renewable energy power consumption, improve the utilization rate of new energy, and alleviate reverse overload of distribution transformers, a configuration strategy of self-owned power sources including wind, solar and energy storage under time-of-use price curve, load guideline and load baseline demand response (DR) is constructed. The constraint of allowing reverse transmission is considered. The effectiveness of participating in three types of DR to reduce total cost of energy consumption is evaluated and compared. [Methods] Taking the minimum total cost of energy consumption as the target, a two-layer optimization model is established, including alternating iterations of self-owned power source configuration during the planning phase and load baseline during the operation phase. The upper model considers the maximum of multiple predicted new energy curves at any time, establishes a self-owned power source configuration model, and solves the capacity of new energy, energy storage, and nominal discharge time. The lower model calculates the mathematical expectation of total cost of energy consumption based on the outcome of the upper model and the probability of multiple predicted new energy curves. The mathematical expectation of transmission curves is used as the load baseline and fed back to the upper model until the results of two consecutive self-owned power source configuration and the load baseline are identical. Via setting the transmission constraint of allowing reverse transmission of not exceeding 20% of the generated electricity of photovoltaic, and adjusting time-of-use price, benchmark incentive price and load guideline, the influence on economic indicators is studied. Taking a certain large commercial complex in a coastal province of China as an example for calculation and evaluation, the effectiveness of the strategy is verified from the perspective of reducing total cost of energy consumption. [Results] From the perspective of mathematical expectation, compared with the control schemes without self-owned power sources, total costs of energy consumption utilizing the proposed model are reduced by 2% to 10%. The similarities when participating in baseline DR are 98% to 100%, which are significantly higher than 82% to 86% when participating in guideline DR. Compared to guideline DR, participating in baseline DR can reduce total cost of energy consumption by 6% to 10%. The proportions of reverse transmission of photovoltaic are 0% to 10%. [Conclusions] The proposed strategy in this paper satisfies the responsibility weight of renewable energy power consumption of provincial power grids, while achieving high similarity between the load baseline and transmission curve. The set constraint of allowing reverse transmission increases the scale of self-owned power sources, significantly reducing total cost of energy consumption of commercials.

[Objective] In response to the increasingly diversified charging demands arising from the rapid development of electric vehicle (EV), this paper investigates a planning method for charging stations based on the collaboration of multiple types of charging posts. [Methods] From the perspectives of EVs, transportation networks, and power grids, a siting and sizing planning method for charging stations under vehicle-road-grid coupling is first established based on graph theory. The charging behavior characteristics of EV users are then explicitly modeled, and four types of charging posts—Slow Charging Post (SCP), Fast Charging Post (FCP), Mobile Charging Post (MCP), and Ultra-fast Charging Post (UCP)—are selected as the main facilities. A planning model is constructed with the objective of minimizing the annualized total social cost, incorporating constraints from multiple scenario conditions and multiple charging post types. The planning problem is then reformulated as a Mixed-Integer Second-Order Cone Programming (MISOCP) problem via scenario transformation and second-order cone relaxation techniques, and solved using the Gurobi optimizer. [Results] Simulation results demonstrate the high efficiency and effectiveness of the proposed model. The results indicate that the planning solution considering SCP, FCP, UCP, and MCP is optimal. Notably, the integration of MCPs provides effective emergency response during peak charging demand periods and reduces the overall planning cost by 17.82%. [Conclusions] In the proposed planning model, EV users can select among multiple types of charging posts based on specific principles. The coordinated configuration of diverse charging posts offers greater flexibility compared to single-type configurations, enabling the satisfaction of charging demands while reducing the annualized total social cost.

[Objective] Under extreme ice disaster weather conditions,the power generation capacity of wind and solar energy experiences a drastic decline,while the probability of power equipment failures increases significantly,leading to severe supply-demand imbalances persisting for multiple days. In order to analyze the complex interdependent relationships among source-grid-load components in high-penetration renewable energy systems during ice storms and identify vulnerable nodes prone to failure propagation,this paper investigates the temporal-spatial distribution patterns,correlations,and stochastic characteristics of source-grid-load systems under ice disaster conditions. The study reveals probabilistic features of both power supply and demand sides,establishing a probabilistic model for source-grid-load systems that incorporates key ice disaster impact factors. [Methods] Based on nonlinear dynamic system theory,we propose three novel indicators：passive/active voltage fluctuation indices for grid nodes,a composite network fluctuation index,and a node voltage violation index. A dynamic impedance matrix and source-load frequency coupling coefficient are introduced to develop an analytical framework for assessing source-grid-load coupling characteristics and vulnerability under ice disaster scenarios. This methodology enables systematic investigation of the synergistic evolution mechanisms and variation patterns within source-grid-load systems during ice events. [Results] Case studies using the modified IEEE 39-node system and a regional grid demonstrate that system-wide passive/active fluctuation indices progressively increase with enhanced nodal interdependencies. The amplified coupling effects from renewable energy fluctuations under ice storms substantially degrade grid resilience. [Conclusions] The proposed approach effectively reveals dynamic evolution patterns of source-grid-load coupling characteristics and identifies critical vulnerable nodes,providing an effective tool for in-depth research on operational characteristics and optimal dispatch strategies for power systems under ice disaster conditions.

With the drive of the “dual carbon” goal and the deepening of the construction of new energy system, renewable sources and novel loads, such as distributed power supply, electric vehicles and controllable user-side resources, have developed rapidly and their proportion has reached new heights. The fluctuation and randomness of these new sources and loads pose new challenges to the safe operation and flexible regulation of the distribution networks, and it is urgent to upgrade the distribution network towards modernity and intelligence. In response to the requirements of the development of modern smart distribution networks, the connotation and characteristics of modern smart distribution networks are analyzed, and the intelligent demands and development priorities of distribution networks are elaborated. In view of the diversity and difference of distribution network construction, the key technologies for upgrading traditional distribution network to modernity and intelligence are preliminarily explored by combining five typical scenarios: coordinated development of micro-grid, efficient carrying capacity of charging facilities, efficient utilization of new energy storage, upgrading of urban and rural distribution network, and efficient coordination of generation, network, load and storage. Finally, based on the connotation, characteristics, and development priorities of modern smart distribution networks, the technical development direction and construction priorities of future distribution networks are prospected.

In the context of "dual carbon", in order to further reduce the carbon emissions of the microgrid system,a low-carbon operation strategy of multi-micro-grid integrated energy system is proposed, which takes into account the coordinated charging of electric vehicles and the reward and punishment type of ladder carbon trading mechanism. Firstly, a dynamic urgency index reflecting the user's charging demand is proposed for the EV load in the microgrid, and a coordinated EV charging model is established to minimize the pek-valley difference of the total electric load in the microgrid. Then, a two-stage power-to-gas, distributed power supply and Cogeneration unit supply cooperative operation model is added to the microgrid. Finally, considering the existence of electrothermal interaction in the multi-microgrid, the carbon emission of the multi-microgrid is restricted by adding the reward and punishment type of ladder carbon trading mechanism, and the low-carbon and economic performance of the multi-microgrid system is further improved. Based on this, a low-carbon economy operation goal with the minimum cost of multi-micro online shopping energy, carbon emission and wind and light abandonment is constructed, and the original problem is transformed into a mixed integer linear programming problem for solving. By comparing cases, the effectiveness of the proposed strategy is analyzed and verified.