风力发电系统大范围功率可调控制研究

Study on Widely-ranged Power-adjustable Control for Wind Turbine Generation Systems

为了从机械侧和电气侧深度管理负荷,分析了现有变速变桨风力发电系统(WTGS)的运行特性,提出在额定风速以下,通过桨距角控制和发电机控制联合调节进行限功率跟踪,给出了变速变桨等多自由度运行模式下的解耦协调控制策略;考虑限功率跟踪与最大功率跟踪的兼容性,建立了WTGS全工况下大范围功率可调的整体控制策略;采用PID增益调度技术,结合非线性测度指标减少工况点划分数量,基于T-S模糊逻辑定义增益调度算法,完成WTGS全工况控制系统的设计.针对2MW容量WTGS的一般非线性模型,在额定风速以下完成了功率跟踪仿真实验.结果表明:该大范围功率可调控制系统能够实现对功率调度值的良好跟踪,使WTGS具备了全面的负荷管理能力.

To deeply manage the load from both the mechanical side and electrical side of wind turbine generation system(WTGS),operation characteristics of variable speed variable pitch WTGS was analyzed,based on which a combined adjustment method composed of pitch control and generator control was proposed for limited power tracking,under the condition below rated wind speed,while the decoupling coordinated control strategy was put forward for variable speed variable pitch mode with multiple degree of freedom.Considering the compatibility of limited power tracking and maximum power tracking,an integrated control strategy was established for WTGS to widely adjust the output power over full range of wind speed.Meanwhile,PID gain scheduling technique was used for process control design over full operating range,where a kind of nonlinear measure index was applied to reduced the number of partioned operation points and the T-S fuzzy logic was adopted to define the gain scheduling algorithm.Simulation tests were finally carried out to a 2MW WTGS based on the nonlinear model.Results show that the power setpoint could be well tracked by the widely-ranged power-adjustable control system,which enables the WTGS to have comprehensive management ability on load.