直驱型波浪发电系统的混沌运动及反步滑模变控制

为研究直驱式波浪发电系统的混沌现象及混沌控制问题,根据直线电机双轴数学模型,将系统转化为类Lorenz混沌方程。通过数值法计算最大Lyapunov指数谱,证明在特定参数和工况下,电机系统会出现混沌运动。通过构造状态反馈解耦,降低混沌系统阶数。采用反步法构造虚拟控制量,针对虚拟控制量设计滑模控制器,构造控制律进行混沌控制,提出反步滑模变控制方案。稳定性分析中,根据Lyapunov稳定性理论,证明了系统的全局一致渐进收敛。仿真结果表明,所设计反步滑模变控制器能使直线电机系统迅速脱离混沌状态,在抑制传统滑模控制中抖振现象的同时,保留了滑模变结构的强鲁棒性,具有一定的优越性。

Chaos Analysis and Backstepping Sliding Mode Control of the Direct-drive Wave Power Generation System

In order to study the chaos phenomenon and chaos control of the direct-drive wave power generation system,the permanent magnet linear synchronous machine(PMLSM) system was transformed into similar Lorenz chaotic equation based on the d-q axis model of PMLSM. At some specific operation status and parameters, the chaos motion of PMLSM was proved by calculating the largest Lyapunov exponents spectra. The order of the chaos system was reduced by constructing the state feedback decoupling controller.The sliding mode controller was designed according to the virtual control quantity constructed by backstepping method. The backstepping sliding mode control strategy was proposed to realize chaos control of PMLSM with constructing control law.The global unanimous asymptotic stability of the PMLSM system was proved via Lyapunov stability analysis.The simulation results show that the proposed backstepping sliding mode controller can inhibit the chattering of traditional sliding control method with preserving the strong robustness of sliding mode variable structure.The PMLSM can quickly escape from the chaotic state with a certain advantage by the control method.