Research On Resilient Optimal Power Dispatch Control Based On Wave-Energy-Converter Arrays

As a type of environmentally friendly renewable energy,wave energy has the advantages of abundant energy storage,large development potential,large energy flow density,and high development value.Compared with other renewable energy such as tidal energy,the development cost is low.Therefore,wave energy development is of great significance to alleviate or even address the problem of current rapid growth in energy demand.Despite the above advantages,there are still many technical problems in the development of wave energy.For example,the environment is highly random and it is difficult to efficiently capture energy;at the same time,it is difficult to effectively protect itself in the harsh marine environment.As a distributed power generation system,wave-energy-converter arrays has the advantages of strong scalability,convenient maintenance,and strong adaptability to the environment.This type of system consists of two types of nodes: wave harvesting device(WHD)node and energy storage(ES)node.These two types of nodes play their respective advantages in the process of energy capture and power generation.For WHD node,the maximum power tracking control can be used to capture the maximum energy of wave energy and improve the energy utilization rate.For ES node,an appropriate energy dispatch algorithm can be designed to stabilize the random power output of WHD node,thereby solving the problem of unstable output power of the system.Therefore,in this paper,the following research is carried out on the resilient optimal power dispatch control based on wave-energy-converter arrays.First,in order to simplify the wave energy extraction process of WHD node,linear permanent magnet generator is selected instead of WHD node as the research object of this paper,and its system structure and energy capture process are mathematically modeled.Among them,the analysis of energy capture process is divided into two types based on regular and irregular waves.The regular wave is modeled as a sinusoidal signal,and after calculating the maximum power carried by the regular wave,the three-phase rectifier and boost circuit are used to process maximum power tracking.Then model the irregular wave into a random signal.The model prediction technology is used to calculate the corresponding maximum power,and then use the above circuit structure to perform maximum power tracking control.Then,in order to stabilize the random power output by WHD node,ES node is introduced and mathematically modeled.ES node can be divided into two parts: supercapacitor and bidirectional DC-DC circuit.Supercapacitor is utilized as energy sources to store and output specific power,while bidirectional DC-DC circuit is used for specific power tracking control of supercapacitor.Next,the optimal power dispatch algorithm that can maximize the power output and suppress the fluctuating power is studied.Among them,in order to ensure the consistency of the power consumption speed of each ES node,a corresponding economic dispatch problem(EDP)is first constructed.Then,for the specific constraint that each ES node can only receive information from neighboring nodes,a corresponding distributed optimal power dispatch algorithm is designed using distributed consistency control theory and eigenvalue perturbation theory,so that the total output power meets user's need when the consumption speed of each ES node is at the same.Finally,due to the network communication layer,distributed systems are vulnerable to abnormality.For this reason,this paper designs the corresponding resilient control strategy.The resilient control strategy is divided into four steps: availability iteration,weight update,isolation judgment and re-adaptation.Among them,during the iterative process of availability,each ES node iterates the availability of the first-order adjacent node based on the information of the second-order adjacent node,and the result is used for the next weight update.At the same time,when the weights are updated,the isolation judgment is performed.When the isolation of the abnormal node occurs,the detection node triggers re-adaptation,so that the entire waveenergy-converter arrays remain stable.