基于状态反馈精确线性化Buck变换器的最优控制

加权矩阵的选取在最优反馈系统的综合设计中具有重要意义。该文基于无源性控制思想，提出一种二次型性能指标。应用状态空间平均建模法，建立电流连续型(current conduction mode，CCM)Buck变换器的仿射非线性模型。采用状态反馈精确线性化方法，推导出非线性状态反馈表达式，实现非线性系统的线性化。进一步，利用二次型最优控制对状态反馈反馈系数进行优化设计。所得控制律简单、容易实现。数值仿真验证了该控制方案的优越性，仿真波形对比分析显示与传统无源性控制方法相比，基于该控制方法的系统静态误差小，启动性能优越，且开关频率固定，对输入电压扰动和负载扰动均具有较强的鲁棒性。

Optimal Control of Buck Converter by State Feedback Linearization

The selecting of weighted matrices plays important role in the synthesis design of optimal feedback control system. This paper proposed a linear quadratic performance target based on passivity considerations. Using the state-space average modeling method, a nonlinear affine model of Buck converter working on current conduction mode (CCM) was set up. The nonlinear system had been realized linearization via state feedback linearization control theory. Further, the feedback coefficients were optimized using the linear quadratic control theory. The control law proposed in this paper has some advantages of being simple, easy to implementation. The validity of the control scheme was verified by numerical simulation results. Key waveforms based on simulated extensive work show that comparing with the passivity-based control method the proposed control system has small steady errors, excellent starting-up response, constant switch frequency, and strong robust to the disturbance of input voltage and load.