基于激励力预估的直驱式波浪发电系统功率优化

POWER OPTIMIZATION OF DIRECT-DRIVEWAVE POWER SYSTEM BASED ON EXCITATION FORCE ESTIMATION

为提高不规则激励力工况下直驱式波浪发电系统的功率捕获能力,基于变分法给出最大功率提取条件,求解得到对应的理想电磁力。结合电机-水动力模型,设计滑模观测器,由Lyapunov函数证明系统稳定性,预估未知波浪不规则激励力输入。以理想电磁力为参考输入,采用空间矢量控制策略跟踪系统期望电流信号,实现最大功率输出。仿真结果表明,所提方案预估精度高,在模型失配时也有较好的鲁棒性,系统输出功率更高,可在线检测激励力,提高复杂海况下系统波能转换率。

Aimed at improving the power capture capability of the direct-drive wave power system under irregular excitation force conditions,the maximum power extraction conditions were given based on the variational method,the corresponding perfect electromagnetic force was obtained by calculating it.In order to predict the unknown excitation force input,a sliding mode observer was designed based on the motor-hydrodynamic model,the system stability was proved by Lyapunov function.Taken the optimal electromagnetic force as the reference input,the desired current signal of the space vector control strategy tracking system is used to achieve the maximum power output.The results show that the proposed scheme has good robustness against model mismatch,higher prediction accuracy and output power of the system.It can detect the excitation force online,and promote the wave energy conversion rate of the system in complex wave conditions.