基于频域的风电场功率波动仿真(一)模型及分析技术

摘要

With the capacity of installed wind power generators steadily increasing in China, power fluctuation from wind farms will significantly affect the security and reliability of the power system. Traditional modeling of power fluctuation is based on the time domain or statistics methodology which, however, is incapable of completely explaining the physical mechanism of randomness of power fluctuation. To remedy such a situation, fluctuation modeling based on the frequency domain is proposed. The frequency domain characteristics of stochastic fluctuation on large wind farms are studied using the power spectral density of wind speed, the frequency domain model of a wind power generator and the information on weather and geography of the wind farms. The correctness and effectiveness of the model are verified by comparing the measurement data with simulation results of a certain wind farm.%随着国内风电装机容量的不断攀升,风电场的随机功率波动将显著影响电力系统的安全可靠运行.现有研究多从时域或统计的角度出发,研究功率波动对电力系统的影响.然而,由于时域或统计的方法无法完整描述功率波动产生的物理机理,其评估结果偏差较大.为了克服以上问题,文中从频域的角度出发,以风速的谱密度函数为基础,结合风电机组的频域模型及风电场天气、地理位置等信息,研究大型风电场随机功率波动的频域特性.相对于传统的时域或统计方法,基于频域的方法物理意义更为清晰,能够针对大型风电场功率波动形成的每一个过程均建立较为准确且实用的模型.通过对比某风电场的实测与仿真数据,验证了所提出方法的正确性和有效性.