含有恒功率负荷的直流微网鲁棒非脆弱模糊控制

Robust Non-fragile Fuzzy Control of DC Microgrid Containing Constant Power Load

当具有恒功率特性的负荷与源侧换流器级联时,会降低直流微网系统的阻尼,带来稳定性问题。针对上述问题,采用TS模糊模型,对含恒功率负荷的非线性直流微网系统进行建模。为有效抵抗直流微网和控制系统参数的不确定性,设计了一种鲁棒非脆弱控制器,在计算参数不确定矩阵的基础上,推导以线性矩阵不等式表示的Lyapunov指数稳定条件。经Matlab/Simulink仿真测试,所设计控制器满足直流微网对于稳定性的要求,能够提高闭环系统的暂态性能,对系统及控制器内部的不确定性拥有较强的鲁棒性。

The damping in DC microgrid will be decreased due to the cascade connection of the load possessing constant power characteristics with the converter at source side and it will affect the stability of the system.In allusion to this problem,the TS fuzzy model was adopted to establish the model for the nonlinear DC microgrid containing constant power load.To effectively resist the uncertainty of DC microgrid and parameters in control system,a robust non-fragile controller was designed,and on the basis of computing parameter uncertainty matrix the Lyapunov exponential stability condition stability condition expressed by linear matrix inequality wad derived.Results of Matlab/Simulink platform based simulation testing show that the designed controller can satisfy the demand of DC microgrid for stability,and can improve the transient performance of the close-loop system;besides,there is a stronger robustness for the uncertainty within the system and the controller.