高柔风电塔残余振动控制优化设计

Optimum design of residual vibration reduction for tall and slender wind turbine tower

高柔风电塔在紧急停机后因共振往往会发生长时间且激烈的残余振动,严重影响风电塔的运行安全.为了确保风电塔的安全运行,提出基于残余振动控制的多约束单管型风电塔的优化方法.由于降低风电塔建造成本的重要性,以最小化材料体积为目标函数,按照将塔架设计成柔性塔的要求设定塔架的固有频率约束,将停机激励下的残余振动降低比例作为约束.为了避免计算残余振动及其灵敏度所需的耗时瞬态动力学分析,采用二次型积分形式的性能指标衡量结构的残余振动.基于李雅普诺夫第二方法实现了对上述性能指标及其灵敏度计算的大幅简化.同时,考虑到风电塔设计中也需考虑塔顶位移约束,为了计算塔顶位移,采用专业软件Bladed得到紧急停机工况下的风荷载.比较了采用塔顶位移约束和残余振动约束的优化结果,同时对阻尼器的分布进行拓扑优化,为高柔风电塔的设计研究提供了一定的参考.

For tall and slender wind turbine towers,the long-time excessive residual vibration due to resonance after emergency shutdown operation causes imminent threat to their safe operation.To ensure the safe operation,a residual vibration control method for optimum design of single-tube type turbine wind towers under multiple constraints is presented.Since it is important to reduce the construction cost of wind turbine towers,the objective function is minimum structural volume and the natural frequency is constrained to ensure the tower a slender design.The residual vibration reduction ratio is constrained to control the effect of emergency shutdown.With the Lyapunov′s second method,the quadratic integral index which measures the residual vibration of structure and its sensitivities are simplified,which avoid the time-consuming transit dynamic analysis for residual vibration and its sensitivities computation.In addition,the constraint on tower top displacement is also taken into account in the design of wind turbine towers.To calculate the displacement at the top of the tower,the professional software Bladed is applied to obtain the wind load at emergency shutdown.The optimum design results with the tower top displacement constraints and the residual vibration constraints are compared and the topology of the damper is optimized,which can provide a reference for design research of tall and slender wind turbine tower.