Reactive Power Optimization of Clustered New Energy Power Stations Considering Active and Reactive Coupling Characteristics of Generating Units

Along with the increasingly grid-connected scale of such new energy as wind power stations and photovoltaic (abbr. PV) stations and the grid-connection of HVDC equipments, the power grid gradually presents the feature of high degree power electronization, and it brings new demands and new challenges to reactive power control. In allusion to this problem, firstly, the dynamic reactive power regulation ability model of doubly fed induction generator (abbr. DFIG), direct-driven wind turbine (abbr. DDWT) and PV were presented. Secondly, a reactive power control strategy, in which the active power was proactively considered to reduce, was proposed, and a reactive power optimization model, in which the active power was considered at the clustered level of new energy stations, was established. Thirdly, by means of combining the Second-order cone-convex relaxation algorithm with piecewise linearization algorithm, a solving method for mixed integer and second-order cone optimization was put forward, by use of this method the difficult nonlinear nonconvex and mixed integer programming problems in the established model were effectively solved. Finally, the simulation-based analysis on the grid-connection system of a certain practical clustered new energy power stations was performed. Simulation results show that adopting this reactive power regulation and control strategy, in which the active power is proactively considered to reduce, the reactive power control ability of the system can be evidently enhanced, and the voltage control effect can be improved, the economy of the system can be ameliorated as well, thus, both the correctness and the economic value of the established model were verified.