Research On Operation Strategy And Optimal Equipment Configuration Method For Distribution Cyber-Physical Systems Considering Uncertainty

Under the backdrop of the "dual-carbon" initiative,the development of grid-connected distributed photovoltaics has rapidly progressed.With the support of policies promoting photovoltaics in entire counties,rooftops,and agriculture,it is anticipated that China’s distributed photovoltaic capacity will reach 1000 GW by 2035.The high penetration of distributed photovoltaics poses multiple challenges to the distribution grid,such as voltage violations and increased network losses.Mitigation measures include energy storage deployment,demand-side resource mobilization,control implementation for photovoltaic inverters,and leveraging the aforementioned flexible resources.This transition from active control to an information-physical system gradually takes place in the distribution system.However,the high-penetration distribution information-physical system faces risks due to the uncertainty arising from weather conditions,new types of loads,as well as faults caused by the multitude of communication infrastructure types and harsh operating environments.These risks jeopardize the operational safety of the system and pose technical challenges concerning the trade-off between safety and costeffectiveness in the configuration of consumption equipment.This paper focuses on the research of distribution information-physical systems,taking into account the dual uncertainties,and explores methods such as optimizing operation control strategies,conducting risk assessment,and configuring control devices to achieve the goal of economically accommodating distributed photovoltaics while ensuring safety.The main contributions and findings of this paper are as follows:(1)This paper proposes a two-layer optimization generation method for coordinated control of distributed photovoltaic(PV)inverters,considering source-load uncertainty,to balance system network losses and short-term voltage violation risks.The upper layer operates at a 15-minute time scale,aiming to minimize the comprehensive system network losses and PV curtailment by optimizing the active and reactive power outputs of the inverters.The lower layer establishes a robust decentralized control model for inverters based on the optimized system voltage state from the upper layer.It takes into account the short-term uncertainty of the source-load and minimizes the voltage fluctuations at PV integration points as the objective.The optimization includes adjusting the voltage-reactive power droop control slope and conducting minute-scale simulation calculations to evaluate the objective function.Simulation results validate the effectiveness of the proposed model and analyze the impact of source-load uncertainty,penetration rate,inverter capacity,and other parameters on the control performance.(2)This paper proposes a voltage risk assessment method for distribution information-physical systems considering the uncertainty of soft-hardware faults to quantify the impact of information system failures on control performance.Firstly,a comprehensive model is established to evaluate the effectiveness of active operation control strategies,taking into account factors such as hardware failures of control devices,packet loss in control command transmission,and software failures.Secondly,a risk assessment index system for voltage violations is proposed based on fault analysis methods.Finally,the effectiveness of the model is verified through simulations,and the impact of fault equipment types,control packet loss probabilities,soft-hardware fault characteristics,and active control strategy modes on system voltage is analyzed.Recommendations for risk control are provided based on the findings.(3)This paper proposes a two-layer optimization method for coordinated configuration of control and energy storage devices in distribution informationphysical systems,considering the uncertainty of source-load variations.Firstly,a upper layer device configuration model is established-considering the cost of operation control devices and energy storage devices.with decision variables including control placement.energy storage capacity.and energy storage power.The objective is to achieve the optimal economic performance from both sides.Secondly.a lower layer interval robust optimization model is developed,aiming to optimize the operation to achieve the optimal balance between network losses and maintenance cost.Finally,the effectiveness of the model is verified through simulations.The impact of voltage risk,energy storage cost,uncertainty,training set size.and confidence level of stochastic optimization on the planning results is analyzed.The proposed method enables the achievement of economic consumption goals while ensuring safety requirements.In conclusion.this paper aims to ensure the safe and economically viable integration of distributed photovoltaics.It addresses three relevant issues in the operation of distribution information-physical systems:operation control strategies,risk assessment,and configuration of control devices.Novel technical approaches are proposed to provide valuable insights for the highpenetration integration of distributed photovoltaics into distribution grids.