Hierarchical Service Quality Regulation Method in Wind Farms Based on Optimal Generating Strategy

Service quality regulation for wind farms (WFs) can improve power generation and reduce operation and maintenance costs. In this paper, a hierarchical service quality optimal regulation method was proposed to achieve optimal system performance while proactively suppressing potential wind turbine (WT) failures. In the upper-lever, a global optimization problem was formulated based on model predictive control to meet the power commands of the transmission system operator and ensure node voltage safety. Then, the optimal power reference solved by the system-level optimization problem was given as input to the lower-level controller. In the lower-lever, tower displacement and converter temperature associated with power output were modeled as WT health indicators and integrated into a multi-objective optimization problem such that the optimization problem could improve the power flow while proactively suppressing WT failures. Thus, the traditional quality index was extended from individual WT health to system-level performance for the strategic generation of WF with higher reliability and improved economics. Case studies in MATLAB/Simulink demonstrated the effectiveness of the proposed method.