考虑风速变化的双馈风电机组暂态能量函数及振荡分析

Transient Energy Function and Oscillation Analysis of Doubly-fed Wind Turbines Considering Variation of Wind Speed

为了研究塔影效应及风剪切对风电机组输出功率的影响,以双馈风电机组为例,首先,计及风速变化,推导双馈感应发电机的暂态能量函数;然后,研究风电机组周期性功率波动特性、频率响应及振荡机理;最后,在PSCAD/EMTDC平台上搭建包含风速模型的单机无穷大系统模型并进行仿真,通过风电机组功率波动及暂态能量的变化,分析塔影效应及风剪切对风电机组的影响。仿真结果表明,塔影效应和风剪切会造成风电机组的功率波动,当机组功率波动频率与风电机组轴系固有振荡频率相等时,风电机组发生共振,振荡幅值最大。

In order to study the influence of tower shadow effect and wind shear on the output power of wind turbines,the doublyfed wind turbines are used as case study.Firstly,the transient energy function of the doubly-fed induction generator is derived by considering the variation of wind speed.Secondly,the periodic power fluctuation characteristics,frequency response,and oscillation mechanism of wind turbines are studied.Finally,a single-machine infinite system model including the wind speed model is built and simulated on the PSCAD/EMTDC platform.The influence of the tower shadow effect and wind shear on wind turbines is analyzed through the variation of power fluctuations and transient energy of wind turbines.The simulation results show that the tower shadow effect and wind shear cause the power fluctuations of the wind turbines.When the power fluctuation frequency of the wind turbines is equal to the natural oscillation frequency of the wind turbine shafting,the resonance of the wind turbines will occur,and the amplitude of oscillation is the largest.