基于改进扰动观察法的直驱波浪发电最大功率跟踪控制

为改善直驱型波浪发电系统在波浪突变情况下的功率捕获效果,分析系统运动频域模型,导出系统输出有功功率与永磁直线发电机等效阻抗的频域空间关系曲线。针对该曲线在三维空间变化特点,提出交替施加变步长扰动的扰动观察法。变步长扰动,易在最大功率点较大范围内陷入局部最优,为此提出依据区域斜率变化,改变扰动步长的控制策略。基于MATLAB/Simulink环境,搭建系统仿真模型,仿真结果表明,在波浪突变情况下,改进控制策略能有效提高系统最大功率跟踪的抗干扰能力,系统能较快地重新追踪到最大功率点附近。

MPPT algorithm for direct-drive wave energy generation based on improved perturbation observation method

In order to improve the power capture effect of the direct drive wave energy generation system at wave mutation, the frequency domain model of the system was analyzed.The relation curve between?the system output active power and the equivalent impedance of permanent magnet linear generator in the frequency domain was derived.According to the characteristics of the curve in three dimensional spaces, a perturbation-observe method was proposed with alternating exerting changed step perturbation.With the changed step perturbation strategy, the system easily traps in local optimum in a wide range of maximum power point.The control strategy was proposed with changing disturbance step size according to regional slope change.The simulation system model was built in Matlab/Simulink environment.The simulation results show that the anti-interference ability of the ameliorative control strategies is improved under the mutational wave conditions, and the system can be quickly to re-track nearby the maximum power point.