中小型风机功率波动的影响因素及量化指标

Influence factors and quantitative indicators of small and medium-sized wind turbine

风电系统输出功率波动导致电能品质下降,并影响系统设备的使用寿命。风电输出功率的波动主要来源于非恒定转矩的变化,为研究中小型风机转矩波动的影响因素,文章从风速特性和机组自身结构特性两方面入手,在时域范围内,研究风速的变化对功率波动幅值的影响,根据实测数据计算得出湍流强度与功率幅值波动随时间尺度的增大而增大;在频域范围内,利用Matlab仿真,得出风剪切和塔影对风速变化均有周期性影响,引起的波动频率为风轮转速频率的3倍。

Wind power system output power fluctuations led to decrease of electrical energy quality, and affect the service life of the system equipment. Wind power fluctuations mainly ascribe to the varia- tion of non-constant torque. In order to evaluate the influence factors of torque fluctuations of small and medium-sized wind turbine ,both wind characteristic and structural property of the unit itself were con- sidered in this article. In time domain, the influence of wind speed change on the power fluctuation amplitude was investigated. The experimental results indicated that the turbulence intensity and power amplitude fluctuations rose with the increase of the time scales. In the frequency domain, the Matlab- Simulink simulation results showed that the variation of the wind shear and tower shadow could cycli- cally impact on the wind speed changes. The fluctuation frequency resulting from the cyclical influence was three times of the rotor rotating speed.