一种适用于永磁直驱风力发电系统的改进 无模型预测控制

An Improved Model Free Predictive Control Suitable for Permanent Magnet Direct Drive Wind Power Generation Systems

永磁直驱风力发电系统运行过程中,机侧的参数变化可能引起控制精度降低、稳定性变差等问题,进而影响变换器的直流母线电压,导致网侧功率波动,对电力系统的稳定性产生危害。机侧采用传统单矢量无模型预测控制时,尽管有效提升了系统鲁棒性,但仍存在控制效果差的问题。为此,提出了一种适用于永磁直驱风力发电系统的改进无模型预测控制,可以保持系统鲁棒性的同时改善稳态控制性能。首先,对系统联合运行时的机侧和网侧模型进行了分析;其次,通过拓展电压矢量的方法对传统有限控制集进行优化,结合传统电流差分无模型预测控制的思想,改善了原有控制方法的预测精度,进一步降低了电流和功率纹波;最后,通过实验对所提方法的有效性和优异性进行了验证。

During the joint operation of permanent magnet direct drive wind power generation systems,the changes in motor side parameters may cause problems such as reduce control accuracy and stability on the machine side,which in turn affects the DC bus voltage of the converter,leading to power fluctuations on the grid side and posing a threat to the stability of the power system.When using traditional single vector model free predictive control on the machine side,although it effectively improves system robustness,there is still a problem of poor control effect.Therefore,an improved model free predictive control suitable for permanent magnet direct drive wind power generation systems was proposed to maintain system robustness while improving steady-state control performance.Firstly,the machine side and grid side models during the joint operation of the system were analyzed.Secondly,through the method of the extended finite control set,the traditional finite control set was optimized.Combined with the model free predictive control concept of traditional current difference,the proposed method improves the prediction accuracy of the control method and reduces current and power ripple.Finally,the effectiveness and superiority of the proposed method were verified through experiments.