Research On Secure Operation Of Active Distribution Network Cyber-physical-social Factors

With the gradual increase of the impact of social factors such as energy trading,policy mechanism and user behavior on the energy system.The concept of cyber-physical system(CPS)has been gradually extended to cyber-physical-social system(CPSS).In addition,due to the large amount of carbon dioxide produced by the generation and transformation of traditional fossil energy,the climate problem has threatened the global ecological stability.Therefore,building a ”new power system with new energy as the main body” is one of the main measures to achieve carbon peak and carbon neutralization.This study intends to conduct collaborative security management for active distribution networks based on CPSS,so as to encourage market competition,guide users to optimize energy consumption structure,improve overall social benefits,and achieve the goals of sustainable energy utilization and carbon emission reduction on the premise of ensuring system security.Specifically,the main research contents and contributions of this paper are as follows:(1)High-precision distributed new energy power generation power prediction is a key foundation for the safety and economic operation of the power system.To improve the accuracy of distributed new energy power generation power prediction,based on Weibull distribution function and beta probability density function,the power generation characteristics of wind and photovoltaic are systematically described and analyzed respectively.A rolling ultra short-term prediction model based on long short-term memory(LSTM)networks is proposed for the related characteristics and uncertainty of wind turbine and photovoltaic output.Through example analysis,based on different prediction evaluation indexes,the prediction results of this prediction method are compared with those of other methods to verify the effectiveness of the proposed method.(2)Aiming at the impact of the penetration of high-proportion new energy in the active distribution networks on the power quality,safety and stable operation of the power system,the model was establishedthe model of wind turbine/photovoltaic/energy storage(WT-PV-ES)combined generation(CG)system is built,and The mechanism of carbon trading to promote greenhouse gas emissions reduction and improve the economy of power system is studied.On the premise of ensuring the safety and stability of the system,aiming at improving the utilization rate of new energy,reducing carbon emission level and the operation and maintenance cost of power generation system,a combined optimal control model of WT-PV-ES based on CPS is constructed.In addition,the security of automatic generation control(AGC)system is also considered,which can further ensure the stable operation of power system.Based on ieee-33 bus system,the optimization calculation and scheme comparison of the example are carried out through CPLEX to verify the good effect of the proposed model.(3)Aiming at the challenges of producers and consumers with dual characters(selling electricity/buying electricity)in energy transformation to energy management,from the design concept of CPSS fusion technology,the structure of each layer and the relationship between each layer in the system including WT-PV-ES CG are studies,and the operation mechanism and topologyand are systematically expounds.In the social system,the charging and discharging models of aggregators and electric vehicle(EV)users are constructed.On the premise of ensuring the safety and stability of the system,improving energy utilization and reducing carbon emissions,considering the minimize the charging cost of EV users,a controllable load scheduling strategy in active distribution networks based on CPSS is established.Among them,to further ensure the stable operation of the power system,the security of AGC system is considered.Based on ieee-33 bus system,the numerical example is solved by CPLEX module,and the optimization results of CPS model are compared to verify the excellent effect of CPSS based optimal scheduling strategy.Secondly,based on the new energy generation power values obtained by different prediction methods,it is verified that the high-precision prediction level can improve the effect of optimal dispatching.(4)For cyber attacks not only destroy the security of the cyber system,but also cause a chain failure of physical and social systems,a multi-area load frequency control(LFC)system including new energy power generation in islanded active distribution networks is constructed,the typical and hybrid FDIAs with different characteristics are defined,and a data-driven detection method is proposed.This method combines fuzzy logic with neural network,which has strong robustness,flexibility and generalization ability.Under different scenarios,two-area and four-area LFC systems are simulated based on MATLAB / Simulink platform.The operation states of the system and attack types are detected under different kinds of FDIAs,and the fault detection results of the improved method are compared with other methods.Numerical examples verify the reliability of the detection method,which can effectively identify and prevent the impact of external malicious attacks on the system,and provide technical support for the safe operation of the system.In summary,combined with the design concept of CPSS integration,this paper deeply studies the prediction,optimization,dispatching and detection of active distribution networks.The results show that this study has obvious advantages and breakthroughs in improving the utilization rate of new energy,reducing carbon emissions and improving the overall economic benefits under the condition of ensuring the safety of the system.