基于双级矩阵变换器的直驱永磁同步风力发电系统有功功率平滑优化控制

Active Power Smoothing Optimization Control of Direct-Driven Permanent Magnet Synchronous Wind Power Generation System Based on Two-Stage Matrix Converter

风能的随机波动性使得风力发电机输出的有功功率随风速变化而波动,影响风力发电机输送到电网的电能质量。在对风电系统传递函数进行推导的基础上,对风电系统的稳定性能进行了分析,并针对现有有功功率平滑控制中存在的风电系统稳定性、功率平滑性和风能利用率之间的矛盾,提出了一种基于模糊指数移动平均(exponential moving average,EMA)算法的有功功率平滑控制策略。该策略同时兼顾了系统稳定性、功率平滑性和风能利用率3个方面的要求,即能够根据风速情况实时对周期数进行调整,使得系统在风速下降时,首先确保风电系统能够安全稳定运行;在风速波动剧烈段,有效抑制风电系统输出有功功率的随机波动;在风速平稳段,提高风能利用率。在Matlab/Simulink仿真平台上搭建了双级矩阵变换器(two-stage matrix converter,TSMC)风电系统模型,仿真结果验证了该控制策略的可行性和有效性。

Random fluctuation of wind energy makes the output active power of wind power generators fluctuated with variation of wind speed~ so the quality of the power transmitted to power grid from wind farm is affected. On the basis of deriving the transfer function of wind power generation system, the stability of wind power generation system is analyzed, and in allusion to^ithe contradictions among system stability, power smoothness and wind energy utilization rate in existing active power smoothing control, a fuzzy exponential moving average （EMA） algorithm based active power smoothing control strategy is proposed. In the proposed strategy the demands on system stability, power smoothness and wind energy utilization rate are simultaneously considered, namely according to the condition of wind speed the real-time adjustment of periodicity is performed, to make the secure and stable operation of wind power system while the wind speed decreases; to effectively suppress random fluctuation during drastic fluctuation of wind speed; and to improve the wind energy utilization rate under stable wind speed. On Matlab/Sirnulink simulation platform a two-stage matrix converter （TSMC） based wind power system model is constructed, and simulation results show that the proposed control strategy is feasible and effective.