Distributed Optimal Power Control Scheme for Structural Loads Minimization in Wind Farms via a Consensus Approach

Abstract

This study proposes a distributed optimal power control (OPC) scheme to reduce the structural loads in WFs for extending the service life of component via a consensus approach. First, a nonlinear cost function of the thrust force and the shaft torque is formulated to minimize structural loads by coordinating the active power and pitch angle of wind turbines (WTs). Then, the nonlinear cost function is linearized via the state variables of WTs and transformed into a linear equation respected to the control variables. Moreover, a fully distributed alternating direction method of multipliers is developed for the optimal structural loads problem to calculate the optimal values of cost function, which could distribute computational burden enhance information privacy protection. Based on the proposed distributed framework, only the intermediate information is exchanged among adjacent WTs controller. More importantly, when several WTs controller occur the communication failure, the communication disconnected WTs can work in decentralized control mode to regulate the pitch angle, and the other WTs with communication still track the power command, which could improve the robustness of the control system. A WF simulation is established as a testing system to verify the effectiveness of the proposed OPC scheme.