Application Of Pirvacy-preserving Based Consensus Algorithm In Microgrid Distributed Energy Optimization And Management

In recent years,due to the shortage of fossil energy and the intensification of environmental pollution,countries all over the world are actively seeking the upgrading of energy structure,and the proportion of new energy power generation such as wind power generation and photovoltaic power generation in the total power generation is gradually increasing.Under this background,this paper studies the distributed energy management of microgrid and the privacy protection in energy management.Firstly,this paper perfects the existing energy management model in the research of microgrid distributed energy management.This paper considers a microgrid system with multiple generation units and responsive load units.Considering that the generation side and load side participate in energy management at the same time,aiming at maximizing social welfare,that is,minimizing generation cost and maximizing user satisfaction,the generation load balance constraints,upper and lower limits of generation unit,generation ramp rate constraints and load unit upper and lower limits of microgrid system are considered,and the power transmission loss is also taken into account,then,a distributed energy management model of microgrid is established.Then,the optimization problem with globally coupled nonconvex constraints is transformed into a convex optimization problem with only local constraints by using convex optimization theory.The optimization problem is decomposed into multiple sub optimization problems,and the optimal scheme is solved by consensus.Two pirvacy-preserving based distributed energy management schemes of microgrid are provided.The first scheme first designs the encryption information interaction strategy for the consensus protocol based on the pailler homomorphic encryption system,so that each unit in the microgrid energy management can complete the information interaction with its neighbor nodes without exposing its own real information.Then the event-triggering mechanism is introduced to solve the problem of excessive system communication and computing burden caused by the secret information interaction strategy.Finally,a homomorphic cryptography based pirvacy-preserving consensus algorithm with event-triggering in distributed energy management(HCPCA)is obtained,and then the convergence,optimality and privacy protection degree of the method are proved theoretically.The second scheme is to add random noise satisfying the truncated Laplace distribution to the consensus protocol based on the differential privacy mechanism.The mean value of the truncated Laplace distribution is zero,and the variance and truncation range converge with the number of iterations.The real information of the node is masked by adding random noise to achieve the purpose of privacy protection,Finally,a differentially privacy based consensus algorithm in distributed energy management(DPEMA)is proposed,and its convergence,optimality and differential privacy are proved theoretically.Finally,two pirvacy-preserving based distributed energy management methods are simulated in IEEE 9 bus system and IEEE 39 bus system to verify the optimality and effectiveness of the algorithm,and the two algorithms have better performance compared with other methods.