双机并联系统离散变结构控制

Discrete variable structure control of two-generator parallel-running system

采用离散变结构控制理论设计双发电机并联系统的稳定和有功平衡控制器,提出一种改进的离散滑模控制算法。采用极点配置方法设计滑模面,基于趋近律方法求取变结构控制律。针对传统趋近律方法稳态抖振的缺点,提出一种具有原点稳定性的离散趋近律,并设计了扰动估计器,通过将离散趋近律方法与自适应控制相结合,较好地消除了抖振,并能够自适应估计参数不确定性及负载干扰对系统的影响,增强系统的鲁棒性。仿真结果表明所提设计方法的有效性。

The discrete variable structure control theory is adopted in the controller design for stability and active power distribution of a two-generator parallel-running system,and a modified discrete sliding mode control algorithm is brought forward. The sliding surface is designed by the ＂pole-placement＂ method and the variable structure control is determined by the ＂reaching law approach＂. To overcome the ＂chattering＂ phenomenon in conventional reaching law approach,a new discrete reaching law,being stable at the origin,is proposed and a disturbance estimator is designed. By combining the discrete reaching law with adaptive control,the new method eliminates chattering effectively and estimates the influences of parameter uncertainties and load disturbances adap- tively,which strengthens the system robustness. Simulative results verify its effectiveness.