傅氏分析反步法直驱型海浪发电系统功率优化控制

为研究波浪发电系统最大波浪能捕获问题,根据浮子的水动力方程和永磁同步直线电机的状态方程,建立了振荡浮子直驱式波浪发电系统的数学模型。提出等效电路图法模拟浮子的水动力模型。针对随机海浪波,采用傅里叶分析法将波浪发电系统分解为多个频率的正弦子系统,分别构造最大功率传输条件实现最大波浪能捕获,优化了传统的控制方法。采用反步法设计控制律,构造Lyapunov函数跟踪发电机状态。仿真结果表明,采用反步法可实现发电机状态的紧密跟踪。在随机波的条件下,所提傅氏分析法对传统算法的优化效果明显,提高了波能转换效率,结合反步法控制发电机可实现最大波浪能捕获,具有一定的实用性。

An optimal control strategy for output power of directly driven wave generation system based on Fourier analysis backstepping method

In order to study the maximum wave energy capture of the wave power generation system, the model of the oscillating buoy direct-drive wave power system was built according to the hydrodynamic equation of the buoy and the state equations of the permanent magnet linear synchronous machine. An equivalent circuit method was proposed to simulate the hydrodynamic equation of the buoy. According to random ocean wave, the wave power generation system was decomposed to multiple sinusoidal subsystem in each frequency by Fourier analysis method. The traditional control method was optimized by constructing the maximum power transmission condition for every subsystem to achieve the maximum wave energy capture. The control law was designed and the Lyapunov function was constructed by backstepping method to track the operation state of generator closely. The simulation results show that the proposed backstepping method can track the state of wave generator closely. Under random ocean wave status, the traditional control algorithm was optimized obviously to increase the conversion efficiency of the wave energy by the proposed Fourier analysis method. The maximum wave energy capture can be achieved by controlling the generator combined with the backstepping method.