考虑到基于转矩调整的改进方法存在难以获取最优调整状态的问题,该文针对传统功率曲线法提出收缩风机转速的跟踪区间、减小跟踪路程的改进思路,以优化风机最大功率点跟踪的性能。在此基础上,设计出根据平均风速,周期性的调整起始发电转速的改进功率曲线法。其设计机理在于风速平均值恰好反映了风速及风能量集中分布的区间。因此,最优转速跟踪区间与平均风速存在数量上的直接关系而变得容易预估,且无需迭代搜索。与目前基于调整转矩的改进方法相比,该文所提方法不仅提高了风能捕获效率,且简单易行。最后,通过对模拟风速序列的仿真计算与比较分析,验证了该方法的有效性和先进性。
The power signal feedback (PSF) method is one of the most important control strategies of wind turbines for maximum power point tracking (MPPT). In order to capture maximum power from wind, the PSF method adjusts the active power (or generator torque) of a wind turbine depending on the predefined power (or torque) curve and the measured rotor speed. Based on the methodology that the acceleration of wind turbines can be assisted by the regulation of generator torque, the performance of the conventional PSF method has been improved by optimizing the definition of power curve. However, it is difficult to determine the optimal definition of power curve due to the random fluctuation of wind speed.