动态入流条件下带控制系统风力机的运行特性模拟

Numerical simulation of wind turbine under dynamic inflow condition with control system

采用基于Open FOAM开发的ALMwindFarmFoam求解器,结合致动线模型与大涡模拟方法对动态入流条件下NREL-5MW风机的运行特性进行数值模拟,研究在不同的转矩控制同PI变桨控制的组合作用下,风力机的转速、转矩、输出功率及叶片气动载荷对动态变化入流风速的响应,并通过与未施加控制的风力机的输出结果对比,探究控制系统对风力机运行特性的影响。数值模拟结果表明:相对于传统的5区域转矩控制,改进后的6区域转矩控制同PI变桨控制的组合应用,使风力机在桨距角恢复阶段的控制失效问题得到解决;并且,风轮转速、气动转矩和输出功率均能较好地响应入流风速的变化,达到设定的运转水平;但在入流风速增加至额定风速的过程中,上述参数的响应均存在一定时间的滞后。此外,风轮叶片所受的气动载荷也由于控制系统的调节得到改善。

In order to investigate the influence of the control system on the operating characteristics of the wind turbine,the ALMwind Farm Foam solver developed based on the actuation line model and large eddy simulation method was used to numerically simulate the operation of the NREL-5 MW wind turbine under dynamic inflow conditions.The numerical results show that compared with the traditional 5-region torque control,under the combined effect of the pitch control and the modified 6-region torque control,the control failure of wind turbine during the pitch angle recovery stage is resolved,in addition,rotor speed,torque and power production of the NREL-5 MW wind turbine can respond well to the change of the inflow wind speed and reach the set operating level.However,in the process of increasing the wind speed from the minimum to the rated value,there is a certain time delay in the response of the above parameters.What’s more,the aerodynamic bending moment and shear force acting at the rotor blades are reduced due to the positive impacts of the control system.