Planning And Optimal Scheduling Of PV-EV-hydrogen System In Active Distribution Networks

In order to achieve the carbon peaking and carbon neutrality goals,the penetration of the renewable energy and renewable energy vehicles such as electric vehicles and hydrogen-based fuel cell vehicles are being boosting.The characteristics of both resources and loads in the distribution network have changed greatly.The multi energy stations supporting the access of new energy vehicles are the main form and development trend to achieve coordination of resources and loads in active distribution networks.However,the renewable energy is mostly accessed by power electronic equipment,which is quite different from traditional generators.Furthermore,the power fluctuation problem becomes more serious due to the increasing penetration of the renewable energy.How to the tap the synergistic potential of power to hydrogen system and electronic vehicles in the dimension of time-space and available controllable region,and how to deploy the complementarity during production,machine,storage,and transportation,is important for the accommodation of the renewable energy and loads in the distribution network.In this background,this paper investigates the planning and operation of the multi-energy station form the following aspects: the impacts of the converter capacity on the fault ride through performances,the coordinated operation of PV-EV-hydrogen,the sizing and operation of multi-energy station,and the operation strategy of gaseous-liquid hydrogen generation and storage station.The contributions of this paper can be summarized as follows:(1)The control capability of the distributed generator is limited to the converter capacity.Therefore,this chapter proposes a capacity optimization method considering fault ride through and voltage support requirements to enhance the voltage support performance and constant power supply to loads.In the optimal model,the awardpunishment mechanism is proposed to coordinate the injected power and load supply power during voltage sags.The converter capacity occupation model under the unbalanced fault conditions is proposed based on the symmetrical component method.For the nonlinear component introduced by the converter capacity constraints,the piecewise linearization method is utilized to transform the original nonlinear model into the mix integer linear model.The fault scenario generation method is formulated to take into account the impact of diverse fault scenarios on optimal results.(2)Due to the uncertain PV generation and charging demand,the coordination of PV and EV will result in the decrease of EV user comfort.Therefore,this chapter proposes a PV-EV-hydrogen coordination method considering the deployment of the hydrogen generation and storage subsystem to mitigate the fluctuations of PV generation,which is able to enhance the EV user comfort.In the optimal model,the charging model is formulated based on the driving pattern of users and parking characteristics of parking lots.The charging demand is estimated with the Monte Carlo simulation.In order to quantify the impact of charging dispatch on EV users,the satisfaction index is formulated.The hydrogen generation and storage system is modeled and deployed based on the electrochemistry and thermodynamics principles.In order to mitigate the influence of uncertainty factors,the model prediction control is utilized.The nonlinear components introduced by the branch flow model are tackled by the second order cone optimization.(3)The charging demand is dispatched to enhance the operation performance and reduce investment operation costs in the planning of power transport integrated system,which will lead to the reduction of EV user comfort.Therefore,this chapter proposes a two-stage planning model for PV-EV-hydrogen multi-energy station in the powertransportation system.In the optimal model,the fast charging model is established based on the traffic volume and driving pattern.According to travel activities and parking lot model,the slow charging model is formulated.Along with hydrogen generation and storage model,the multi-energy carriers multi-time scale coordination strategy is proposed based on the complementarity between hydrogen and charging energy.In order to tackle the nonlinear components introduced by traffic and power follow,the piecewise linearization and second order cone optimization are utilized.(4)The operation costs reduction is important for the development of hydrogen generation and storage plants.Therefore,this chapter proposes a power to gaseousliquid hydrogen generation and storage strategy considering the complementarity of different state hydrogen carriers in hydrogen generation,machine,storage and transportation process.In the optimal model,the power to gaseous-liquid hydrogen model is established based on the electrochemistry and thermodynamics principle.In order to track the path of energy from flow in to flow out the system,the energy coupling matrix is formulated.The proposed optimal model is able to serve both transportation system and power system through hydrogen selling and demand response.With the optimal operation method,the energy dispatch factors for gaseousliquid hydrogen generation are optimized,and the operation can allocated in lower electricity price period.The scenario method is utilized to tackle the impacts of uncertainty factors.This paper investigate the planning and optimal scheduling of the multi-energy station in the active distribution system,including the requirements of fault ride through for converter capacity,the effect of PV-hydrogen coordination for EV user comfort enhancement,the complementarity of different state hydrogen carriers in hydrogen generation,machine,storage and distribution process,which enhance the accommodation capabilities of renewable energy and new type load.