| In recent years,affected by climate change and human activities,the frequency.scope,and destructiveness of extreme events around the world have been increasing.With the expansion of the power grid scale and the strengthening of interconnection.it is increasingly difficult to maintain the normal power supply under extreme events.In the energy transformation environment of the "carbon peaking and carbon neutrality" goal,the traditional UDS gradually transforms into an observable and controllable multi-energy integrated UDS.The urban distribution system(UDS)is an essential part of the urban power grid,located at the end of the urban power grid.directly connected to critical loads with high load density and high importance.The research on the resilience of UDSs with multi-energy integration has social.environmental,and economic benefits that cannot be ignored.Under the above background,this dissertation researches assessing and enhancing UDS resilience with multi-energy integration.Expanding the stage division of resilience research from three stages,i.e.,"prevention","response",and "recovery" to four stages,i.e.,"planning","preparation","response",and "recovery." Build UDS resilience assessment metrics suitable for different stages and dimensions.Explore the resilience enhancement strategy of UDSs with multiple measures.The influence of multi-energy integration characteristics on UDS resilience is studied.The main work and innovation are as follows:(1)In order to adapt to the transformation of the multi-energy integration of UDSs and the complex interdependence between subsystems,this dissertation proposes the multi-dimensional and multi-stage comprehensive resilience assessment metrics for multi-energy integrated UDSs.The comprehensive resilience assessment metrics describe the performance of various stages and subsystems of the multi-energy integrated UDS affected by extreme events from the perspective of "system performance analysis" and "system characteristics analysis".Based on the system performance analysis,the comprehensive resilience assessment metrics include performance maintenance,resistance,responsiveness,and recovery.Based on the analysis of system characteristics,comprehensive resilience assessment metrics include the island connectivity degree,number of islands converged power supply,and critical load maintenance time.The comprehensive resilience assessment metrics measure and evaluate the resilience of UDSs in multiple dimensions and stages and help operators comprehensively and accurately grasp the system performance during extreme events.(2)In the planning stage of UDSs design and(re)construction period,in order to utilize the information and characteristics of extreme events and adapt to the risk aversion preferences of different decision makers,this dissertation proposes a resilience enhancement planning method considering the knowability of extreme events characteristics.According to how much information decision makers have about extreme events,two types of decision makers are distinguished,i.e.,relatively conservative decision makers with information support and extremely conservative decision makers without information support.Analyze the different strategies formed by different decision makers in UDSs planning to improve resilience under different risk aversion preferences.For relatively conservative decision makers with information support,taking typhoons as an example,combining stochastic optimization with information gap decision theory(IGDT)risk avoidance strategy,the distribution system is planned and designed in a targeted manner while achieving the purpose of saving investment costs and avoiding risks.For extremely conservative decision makers without information support.IGDT risk aversion strategy provides a planning strategy to minimize the risk of unknown extreme events under different performance expectations.(3)In the pre-preparation stage when facing impending extreme events,it may be more challenging to maintain and restore the system performance during and after the extreme event if no effective preparation measures are actively taken.To ensure the regular and sustainable operation of the UDSs and prepare for the impending extreme events,this dissertation proposes a resilience reserve enhancement method.The concept of "resilience reserve" derived from "resilience" and the source-pathterminal index used to quantify the resilience reserve capability of UDSs are presented before the arrival of extreme events.The order distribution and charging scheduling problem of ride-hailing electric vehicles.which are easier to manage and more sensitive to the charging price,is modeled as a semi-Markov decision process;An interactive deep reinforcement learning framework is proposed to realize the information interaction and revenue coordination between the power grid dispatching center and the ride-hailing platform.The proposed method can significantly improve the resilience reserve of the power grid dispatching center without substantially reducing the ride-hailing platform’s overall order revenue,promote renewable energy consumption,and support the recovery of critical loads.(4)In order to deal with the interaction of resilience enhancement measures at different stages,this dissertation proposes a multi-stage tri-level defender-attackerdefender(DAD)co-optimization model,considering the full-time sequence of extreme events.The tri-level DAD model regards the extreme events as "attackers" and regards resilience enhancement measures at different stages as two types of "defenders" before and after the "attacker" attack to realize the coordination between resilience enhancement measures at multiple stages in the variation of system performance with extreme events from the system level.Taking the ice storms with distinct characteristics of "occurrence-evolution-disaster" as an example,the model of its attack on the UDSs and urban transportation systems is established.The impact of ice storms with different attack types and intensities on the UDSs and transportation systems is discussed in detail.Comprehensively analyze the effects of various measures on the improvement of system resilience,as well as the coordination and interaction between various measures in the stages of "planning","preparation"."response",and "recovery".(5)In order to further consider the interdependence of multi-energy integrated systems,as well as the complementarity and substitution of various types of energy.the multi-energy integrated systems and coupling elements,including natural gas systems,heating systems,and transportation systems,are modeled.With the development of computer technology and the Internet industry,the data center and its waste heat reuse and computer technology are considered,and the impact of data centers as the emerging critical loads on the resilience of UDSs is systematically analyzed,and the effect of providing support for the improvement of UDSs resilience as energy.Conduct a comprehensive study of resilience assessment and enhancement.consider the correlation between multi-dimensional and multi-stage resilience assessment metrics and enhancement measures,and analyze the contribution and impact of different resilience enhancement measures on various resilience assessment metrics.The comprehensive assessment metrics of resilience can comprehensively and accurately evaluate the system performance from the two aspects of system performance characteristics and topology characteristics to formulate more targeted solutions and countermeasures.The proposed co-optimization method for resilience enhancement can realize the coordinated utilization and effective cooperation among various subsystems and measures and enhance the ability of multienergy integrated UDSs to resist extreme events and recover from extreme events.Considering the dynamic characteristics of the natural gas and heating systems,on the one hand,it can improve the accuracy of system modeling and analysis:on the other hand,it can excavate and utilize the linepack storage resources and the thermal inertia of buildings.The linepack storage and thermal inertia of buildings with the characteristics of "virtual energy storage" are taken as the unique available resources under the influence of extreme events,and their role and impact on the resilience enhancement of multi-energy integrated UDSs are analyzed. |
