Research On Optimal Frequency Control Strategy Of Power System Based On Distributed Algorithm

Under the background of building a new power system with new energy as the main body,private and public investment has been steadily turning to renewable energy,resulting in increasing penetration of renewable energy generation in the grid.While renewable power generation is inherently volatile and intermittent,large infiltrations will lead to more frequent imbalances between generation and load demand,resulting in frequency shifts that can compromise power quality,damage equipment,and even cause power outages,which brings additional challenges to the safe and stable operation of the power grid.Therefore,maintaining frequency stability is an important subject in power grid system research.In view of the above problems,based on the existing research results,using the mature theoretical knowledge such as algebraic graph theory,control theory and distributed control technology,this paper designs distributed control strategies from the generation side and load side to solve the problem of optimal frequency regulation of power system.The main research work is summarized as follows:(1)The distributed optimal frequency regulation problem in the power network is considered while ensuring system stability and optimal power distribution.Aiming at the limitations of the existing control scheme,a control scheme is proposed from the power generation side,which can ensure the system stability and the optimality of power distribution,and the frequency can recover to the rated value in the steady state.The new controller includes design parameters that affect system stability and optimality.The parameters of the controller are selected by solving linear matrix inequalities(LMIs).Furthermore,using real numerical data,it is demonstrated how the proposed control strategy can be applied to various steam turbine governor dynamics.Finally,the practicability of the analysis is verified by numerical simulation on the NPCC 140-bus system through the step-by-step loading load control strategy.The simulation results show that the new controller achieves the convergence to the rated frequency and the economical optimal power distribution,and the performance is significantly improved compared with the existing schemes.(2)Taking advantage of the active control capability of electric vehicles,a distributed control scheme is designed to solve the optimal economic dispatch problem from the load side.Firstly,an optimization model of load balancing is proposed,and the clustered electric vehicles after load balancing are sequentially merged into the power grid.Then,the multi-agent consensus algorithm is applied,and the incremental cost of the generator set and the incremental benefit of the aggregate electric vehicle are used as the consistency variables to design an algorithm for the aggregate electric vehicle to participate in the economic dispatch of the power system,and solve the economic dispatching question through the distributed optimization method.Solve the problem of economic dispatch.Four typical simulation scenarios are established,and numerical examples are simulated on the IEEE 39-bus system to verify the effectiveness of the proposed scheduling strategy.(3)When electric vehicles participate in the economic dispatch of the power system from the load side,electric vehicle users are bounded rationality individuals.When interacting with the power grid,the social-physical integration is considered.The concept of stubborn agent is introduced,and the distributed control algorithm with the characteristics of stubborn agent is applied to analyze the complexity of electric vehicles participating in distributed economic dispatch of power system under bounded rationality.25 figures,4 tables and 96 references.