Research On Electricity Trading Of Photovoltaic Microgrid Based On Blockchain Technology

In recent years,with the rapid development of distributed photovoltaic industry,the installed capacity of household photovoltaic system installed on the roof is also gradually increasing.According to relevant data,in the first three quarters of 2019,the installed capacity of domestic photovoltaic system has reached 4.294 GW,occupied 26.9% of the newly installed capacity of photovoltaic system.With the support of policy,the potential for Chinese household photovoltaic development is huge.As a new type of power resource networking mode,microgrid can realize the efficient energy management of local distributed photovoltaic to improve the reliability of power supply for photovoltaic home users and provide technical support for power transactions between users.In microgrid,the electric energy transaction between photovoltaic home users can improve the efficiency of energy utilization,but it also brings various challenges and security risks,such as the transaction data between users aren't transparent,the transaction data are easily tampered,the users' privacies are easily divulged,users lack the enthusiasm to participate in the transaction,etc.These problems will threaten the security of microgrid information system and the reliability of power supply,which is not conducive to the optimal management of photovoltaic home user resources in microgrid.Therefore,this paper introduces the blockchain technology to provide an effective solution for the above problems.The main research work is as follows.(1)In order to create a safe electricity trading environment for photovoltaic home users in micro grid and design an electricity transaction platform based on block chain is designed,the author respectively introduces the functions of smart meter,identity chain and transaction chain of this platform framework.Then,the multi-layer mechanism design of application layer,incentive layer and consensus layer based on blockchain infrastructure is carried out,which provides the overall research ideas for entire paper.Finally,the asymmetric encryption technology and smart contract technology in the core technology of blockchain are used to design the power transaction mechanism,so as to ensure the security of transactions between photovoltaic home users in microgrid and the independent flexibility of power settlement.(2)Based on the contract theory,the incentive model of electric energy transaction is established,which encourages the photovoltaic household electricity users in the microgrid to sell more surplus electric energy in the electric energy trading platform,and realize the profit maximization of photovoltaic household electricity users.In the simulation,the electric energy transaction between photovoltaic home users under incomplete information symmetry is simulated,and the feasibility and effectiveness of the incentive model are verified by comparing several incentive schemes.(3)In order to ensure the security and consistency of transaction data and information between photovoltaic home users in the transaction chain block,a DPo S(entrusted equity certification)mechanism based on reputation value is designed.The photovoltaic home electricity selling user with high reputation value acts as the "miner" and is in charge of the audit and verification of transaction data and information,and records the successful verified information in the transaction chain block.Then,based on the single weight and heavy subjective logic method,the reputation value of photovoltaic home electricity users is calculated.Finally,the performance of the designed consensus mechanism is verified by experimental simulation.