新趋近律的直流微电网母线电压滑模控制设计

Design of DC Microgrid Bus Voltage Sliding Mode Controller Based on New Reaching Law

随着直流微电网技术的快速发展,直流微电网中母线电压的稳定性控制作为直流微电网正常平稳运行的关键,也成为了研究热点之一;针对直流微电网母线电压外环易受参数摄动和负荷扰动的影响,提出了一种扩张状态扰动观测器ESO(extend state observer)与新型趋近律的滑模控制器NRSMC(new reaching law sliding mode control)相结合的复合控制器ESO-NRSMC;该控制器采用了一种新型趋近律方法来解决抖振现象与滑模面趋近时间之间的矛盾;同时扩张状态观测器将观测到的扰动值补偿到滑模控制器中,进一步提高控制器的抗扰动能力;还构造了Lyapunov函数来验证所设计的母线电压外环闭环控制系统的稳定性;最后通过仿真证明控制器ESO-NRSMC在微电网系统参数发生变化以及负载扰动的情况下,依然能够实现对直流微电网母线电压的稳定控制,具有较强的优越性和鲁棒性能。

With the rapid development of DC microgrid technology,as the key to the normal and stable operation of the DC microgrid,the stability control of bus voltage in the DC microgrid has also become one of the research hotspots;Aiming at the influences of parameter perturbation and load disturbance on the voltage outer loop of the DC microgrid bus,a compound controller ESO-NRSMC combining extended state observer(ESO)with new reaching law sliding mode controller(NRSMC)is proposed;The controller adopts a new approach law method to solve the contradiction between the chattering phenomenon and the approach time of sliding mode surface;At the same time,the extended state observer compensates the observed disturbance value into the sliding mode controller to further improve the anti-disturbance ability of the controller;The Lyapunov function is also constructed to verify the stability of the designed control system with the bus voltage outer closed-loop;Finally,the simulation result shows that the controller ESO-NRSMC can still realize the stable control of the DC microgrid bus voltage under the conditions of the microgrid system parameters variation and load disturbance,which has strong superiority and robustness.